* [PATCH v10 00/19] Add Mediated device support
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
This series adds Mediated device support to Linux host kernel. Purpose
of this series is to provide a common interface for mediated device
management that can be used by different devices. This series introduces
Mdev core module that creates and manages mediated devices, VFIO based
driver for mediated devices that are created by mdev core module and
update VFIO type1 IOMMU module to support pinning & unpinning for mediated
devices.
What changed in v10?
vfio:
- Split commits in multple individual commits.
- Removed the function added in v9 to get device_api string.
- Defined constant strings in include/uapi/linux/vfio.h that should be used by
vendor driver for device_api attribute.
vfio_iommu_type1:
- Fixed accounting when pass through device is unplugged while mdev device
exist in a domain.
- Added blocking notifier to notify DMA_UNMAP to vendor driver to invalidate
mappings.
- Exported APIs to register notifier for DMA_UNMAP action.
Documentation:
- Added sysfs ABI for mediated device framework.
- Updated Documentation/vfio-mdev/vfio-mediated-device.txt.
- Updated mtty.c with bug fixes.
Kirti Wankhede (19):
vfio: Mediated device Core driver
vfio: VFIO based driver for Mediated devices
vfio: Rearrange functions to get vfio_group from dev
vfio: Common function to increment container_users
vfio iommu: Added pin and unpin callback functions to
vfio_iommu_driver_ops
vfio iommu type1: Update arguments of vfio_lock_acct
vfio iommu type1: Update argument of vaddr_get_pfn()
vfio iommu type1: Add find_iommu_group() function
vfio iommu type1: Add support for mediated devices
vfio iommu: Add blocking notifier to notify DMA_UNMAP
vfio: Introduce common function to add capabilities
vfio_pci: Update vfio_pci to use vfio_info_add_capability()
vfio: Introduce vfio_set_irqs_validate_and_prepare()
vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
vfio: Define device_api strings
docs: Add Documentation for Mediated devices
docs: Sysfs ABI for mediated device framework
docs: Sample driver to demonstrate how to use Mediated device
framework.
Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++
Documentation/vfio-mdev/Makefile | 13 +
Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
Documentation/vfio-mdev/vfio-mediated-device.txt | 398 ++++++
drivers/vfio/Kconfig | 1 +
drivers/vfio/Makefile | 1 +
drivers/vfio/mdev/Kconfig | 17 +
drivers/vfio/mdev/Makefile | 5 +
drivers/vfio/mdev/mdev_core.c | 384 ++++++
drivers/vfio/mdev/mdev_driver.c | 122 ++
drivers/vfio/mdev/mdev_private.h | 41 +
drivers/vfio/mdev/mdev_sysfs.c | 286 ++++
drivers/vfio/mdev/vfio_mdev.c | 148 +++
drivers/vfio/pci/vfio_pci.c | 78 +-
drivers/vfio/platform/vfio_platform_common.c | 31 +-
drivers/vfio/vfio.c | 322 ++++-
drivers/vfio/vfio_iommu_type1.c | 808 ++++++++++--
include/linux/mdev.h | 167 +++
include/linux/vfio.h | 30 +-
include/uapi/linux/vfio.h | 10 +
20 files changed, 4270 insertions(+), 206 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
create mode 100644 Documentation/vfio-mdev/Makefile
create mode 100644 Documentation/vfio-mdev/mtty.c
create mode 100644 Documentation/vfio-mdev/vfio-mediated-device.txt
create mode 100644 drivers/vfio/mdev/Kconfig
create mode 100644 drivers/vfio/mdev/Makefile
create mode 100644 drivers/vfio/mdev/mdev_core.c
create mode 100644 drivers/vfio/mdev/mdev_driver.c
create mode 100644 drivers/vfio/mdev/mdev_private.h
create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
create mode 100644 drivers/vfio/mdev/vfio_mdev.c
create mode 100644 include/linux/mdev.h
--
2.7.0
^ permalink raw reply [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 00/19] Add Mediated device support
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
This series adds Mediated device support to Linux host kernel. Purpose
of this series is to provide a common interface for mediated device
management that can be used by different devices. This series introduces
Mdev core module that creates and manages mediated devices, VFIO based
driver for mediated devices that are created by mdev core module and
update VFIO type1 IOMMU module to support pinning & unpinning for mediated
devices.
What changed in v10?
vfio:
- Split commits in multple individual commits.
- Removed the function added in v9 to get device_api string.
- Defined constant strings in include/uapi/linux/vfio.h that should be used by
vendor driver for device_api attribute.
vfio_iommu_type1:
- Fixed accounting when pass through device is unplugged while mdev device
exist in a domain.
- Added blocking notifier to notify DMA_UNMAP to vendor driver to invalidate
mappings.
- Exported APIs to register notifier for DMA_UNMAP action.
Documentation:
- Added sysfs ABI for mediated device framework.
- Updated Documentation/vfio-mdev/vfio-mediated-device.txt.
- Updated mtty.c with bug fixes.
Kirti Wankhede (19):
vfio: Mediated device Core driver
vfio: VFIO based driver for Mediated devices
vfio: Rearrange functions to get vfio_group from dev
vfio: Common function to increment container_users
vfio iommu: Added pin and unpin callback functions to
vfio_iommu_driver_ops
vfio iommu type1: Update arguments of vfio_lock_acct
vfio iommu type1: Update argument of vaddr_get_pfn()
vfio iommu type1: Add find_iommu_group() function
vfio iommu type1: Add support for mediated devices
vfio iommu: Add blocking notifier to notify DMA_UNMAP
vfio: Introduce common function to add capabilities
vfio_pci: Update vfio_pci to use vfio_info_add_capability()
vfio: Introduce vfio_set_irqs_validate_and_prepare()
vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
vfio: Define device_api strings
docs: Add Documentation for Mediated devices
docs: Sysfs ABI for mediated device framework
docs: Sample driver to demonstrate how to use Mediated device
framework.
Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++
Documentation/vfio-mdev/Makefile | 13 +
Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
Documentation/vfio-mdev/vfio-mediated-device.txt | 398 ++++++
drivers/vfio/Kconfig | 1 +
drivers/vfio/Makefile | 1 +
drivers/vfio/mdev/Kconfig | 17 +
drivers/vfio/mdev/Makefile | 5 +
drivers/vfio/mdev/mdev_core.c | 384 ++++++
drivers/vfio/mdev/mdev_driver.c | 122 ++
drivers/vfio/mdev/mdev_private.h | 41 +
drivers/vfio/mdev/mdev_sysfs.c | 286 ++++
drivers/vfio/mdev/vfio_mdev.c | 148 +++
drivers/vfio/pci/vfio_pci.c | 78 +-
drivers/vfio/platform/vfio_platform_common.c | 31 +-
drivers/vfio/vfio.c | 322 ++++-
drivers/vfio/vfio_iommu_type1.c | 808 ++++++++++--
include/linux/mdev.h | 167 +++
include/linux/vfio.h | 30 +-
include/uapi/linux/vfio.h | 10 +
20 files changed, 4270 insertions(+), 206 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
create mode 100644 Documentation/vfio-mdev/Makefile
create mode 100644 Documentation/vfio-mdev/mtty.c
create mode 100644 Documentation/vfio-mdev/vfio-mediated-device.txt
create mode 100644 drivers/vfio/mdev/Kconfig
create mode 100644 drivers/vfio/mdev/Makefile
create mode 100644 drivers/vfio/mdev/mdev_core.c
create mode 100644 drivers/vfio/mdev/mdev_driver.c
create mode 100644 drivers/vfio/mdev/mdev_private.h
create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
create mode 100644 drivers/vfio/mdev/vfio_mdev.c
create mode 100644 include/linux/mdev.h
--
2.7.0
^ permalink raw reply [flat|nested] 119+ messages in thread
* [PATCH v10 01/19] vfio: Mediated device Core driver
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Design for Mediated Device Driver:
Main purpose of this driver is to provide a common interface for mediated
device management that can be used by different drivers of different
devices.
This module provides a generic interface to create the device, add it to
mediated bus, add device to IOMMU group and then add it to vfio group.
Below is the high Level block diagram, with Nvidia, Intel and IBM devices
as example, since these are the devices which are going to actively use
this module as of now.
+---------------+
| |
| +-----------+ | mdev_register_driver() +--------------+
| | | +<------------------------+ __init() |
| | mdev | | | |
| | bus | +------------------------>+ |<-> VFIO user
| | driver | | probe()/remove() | vfio_mdev.ko | APIs
| | | | | |
| +-----------+ | +--------------+
| |
| MDEV CORE |
| MODULE |
| mdev.ko |
| +-----------+ | mdev_register_device() +--------------+
| | | +<------------------------+ |
| | | | | nvidia.ko |<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| | Physical | |
| | device | | mdev_register_device() +--------------+
| | interface | |<------------------------+ |
| | | | | i915.ko |<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| | | |
| | | | mdev_register_device() +--------------+
| | | +<------------------------+ |
| | | | | ccw_device.ko|<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| +-----------+ |
+---------------+
Core driver provides two types of registration interfaces:
1. Registration interface for mediated bus driver:
/**
* struct mdev_driver - Mediated device's driver
* @name: driver name
* @probe: called when new device created
* @remove:called when device removed
* @driver:device driver structure
*
**/
struct mdev_driver {
const char *name;
int (*probe) (struct device *dev);
void (*remove) (struct device *dev);
struct device_driver driver;
};
Mediated bus driver for mdev device should use this interface to register
and unregister with core driver respectively:
int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
void mdev_unregister_driver(struct mdev_driver *drv);
Mediated bus driver is responsible to add/delete mediated devices to/from
VFIO group when devices are bound and unbound to the driver.
2. Physical device driver interface
This interface provides vendor driver the set APIs to manage physical
device related work in its driver. APIs are :
* dev_attr_groups: attributes of the parent device.
* mdev_attr_groups: attributes of the mediated device.
* supported_type_groups: attributes to define supported type. This is
mandatory field.
* create: to allocate basic resources in vendor driver for a mediated
device. This is mandatory to be provided by vendor driver.
* remove: to free resources in vendor driver when mediated device is
destroyed. This is mandatory to be provided by vendor driver.
* open: open callback of mediated device
* release: release callback of mediated device
* read : read emulation callback.
* write: write emulation callback.
* mmap: mmap emulation callback.
* ioctl: ioctl callback.
Drivers should use these interfaces to register and unregister device to
mdev core driver respectively:
extern int mdev_register_device(struct device *dev,
const struct parent_ops *ops);
extern void mdev_unregister_device(struct device *dev);
There are no locks to serialize above callbacks in mdev driver and
vfio_mdev driver. If required, vendor driver can have locks to serialize
above APIs in their driver.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I73a5084574270b14541c529461ea2f03c292d510
---
drivers/vfio/Kconfig | 1 +
drivers/vfio/Makefile | 1 +
drivers/vfio/mdev/Kconfig | 10 +
drivers/vfio/mdev/Makefile | 4 +
drivers/vfio/mdev/mdev_core.c | 384 +++++++++++++++++++++++++++++++++++++++
drivers/vfio/mdev/mdev_driver.c | 122 +++++++++++++
drivers/vfio/mdev/mdev_private.h | 41 +++++
drivers/vfio/mdev/mdev_sysfs.c | 286 +++++++++++++++++++++++++++++
include/linux/mdev.h | 167 +++++++++++++++++
9 files changed, 1016 insertions(+)
create mode 100644 drivers/vfio/mdev/Kconfig
create mode 100644 drivers/vfio/mdev/Makefile
create mode 100644 drivers/vfio/mdev/mdev_core.c
create mode 100644 drivers/vfio/mdev/mdev_driver.c
create mode 100644 drivers/vfio/mdev/mdev_private.h
create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
create mode 100644 include/linux/mdev.h
diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
index da6e2ce77495..23eced02aaf6 100644
--- a/drivers/vfio/Kconfig
+++ b/drivers/vfio/Kconfig
@@ -48,4 +48,5 @@ menuconfig VFIO_NOIOMMU
source "drivers/vfio/pci/Kconfig"
source "drivers/vfio/platform/Kconfig"
+source "drivers/vfio/mdev/Kconfig"
source "virt/lib/Kconfig"
diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
index 7b8a31f63fea..4a23c13b6be4 100644
--- a/drivers/vfio/Makefile
+++ b/drivers/vfio/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
obj-$(CONFIG_VFIO_SPAPR_EEH) += vfio_spapr_eeh.o
obj-$(CONFIG_VFIO_PCI) += pci/
obj-$(CONFIG_VFIO_PLATFORM) += platform/
+obj-$(CONFIG_VFIO_MDEV) += mdev/
diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
new file mode 100644
index 000000000000..303c14ce2847
--- /dev/null
+++ b/drivers/vfio/mdev/Kconfig
@@ -0,0 +1,10 @@
+
+config VFIO_MDEV
+ tristate "Mediated device driver framework"
+ depends on VFIO
+ default n
+ help
+ Provides a framework to virtualize devices.
+ See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
+
+ If you don't know what do here, say N.
diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
new file mode 100644
index 000000000000..31bc04801d94
--- /dev/null
+++ b/drivers/vfio/mdev/Makefile
@@ -0,0 +1,4 @@
+
+mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
+
+obj-$(CONFIG_VFIO_MDEV) += mdev.o
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
new file mode 100644
index 000000000000..9d8fa5c91c2e
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -0,0 +1,384 @@
+/*
+ * Mediated device Core Driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+#include <linux/sysfs.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "NVIDIA Corporation"
+#define DRIVER_DESC "Mediated device Core Driver"
+
+static LIST_HEAD(parent_list);
+static DEFINE_MUTEX(parent_list_lock);
+static struct class_compat *mdev_bus_compat_class;
+
+static int _find_mdev_device(struct device *dev, void *data)
+{
+ struct mdev_device *mdev;
+
+ if (!dev_is_mdev(dev))
+ return 0;
+
+ mdev = to_mdev_device(dev);
+
+ if (uuid_le_cmp(mdev->uuid, *(uuid_le *)data) == 0)
+ return 1;
+
+ return 0;
+}
+
+static bool mdev_device_exist(struct parent_device *parent, uuid_le uuid)
+{
+ struct device *dev;
+
+ dev = device_find_child(parent->dev, &uuid, _find_mdev_device);
+ if (dev) {
+ put_device(dev);
+ return true;
+ }
+
+ return false;
+}
+
+/* Should be called holding parent_list_lock */
+static struct parent_device *__find_parent_device(struct device *dev)
+{
+ struct parent_device *parent;
+
+ list_for_each_entry(parent, &parent_list, next) {
+ if (parent->dev == dev)
+ return parent;
+ }
+ return NULL;
+}
+
+static void mdev_release_parent(struct kref *kref)
+{
+ struct parent_device *parent = container_of(kref, struct parent_device,
+ ref);
+ struct device *dev = parent->dev;
+
+ kfree(parent);
+ put_device(dev);
+}
+
+static
+inline struct parent_device *mdev_get_parent(struct parent_device *parent)
+{
+ if (parent)
+ kref_get(&parent->ref);
+
+ return parent;
+}
+
+static inline void mdev_put_parent(struct parent_device *parent)
+{
+ if (parent)
+ kref_put(&parent->ref, mdev_release_parent);
+}
+
+static int mdev_device_create_ops(struct kobject *kobj,
+ struct mdev_device *mdev)
+{
+ struct parent_device *parent = mdev->parent;
+ int ret;
+
+ ret = parent->ops->create(kobj, mdev);
+ if (ret)
+ return ret;
+
+ ret = sysfs_create_groups(&mdev->dev.kobj,
+ parent->ops->mdev_attr_groups);
+ if (ret)
+ parent->ops->remove(mdev);
+
+ return ret;
+}
+
+/*
+ * mdev_device_remove_ops gets called from sysfs's 'remove' and when parent
+ * device is being unregistered from mdev device framework.
+ * - 'force_remove' is set to 'false' when called from sysfs's 'remove' which
+ * indicates that if the mdev device is active, used by VMM or userspace
+ * application, vendor driver could return error then don't remove the device.
+ * - 'force_remove' is set to 'true' when called from mdev_unregister_device()
+ * which indicate that parent device is being removed from mdev device
+ * framework so remove mdev device forcefully.
+ */
+static int mdev_device_remove_ops(struct mdev_device *mdev, bool force_remove)
+{
+ struct parent_device *parent = mdev->parent;
+ int ret;
+
+ /*
+ * Vendor driver can return error if VMM or userspace application is
+ * using this mdev device.
+ */
+ ret = parent->ops->remove(mdev);
+ if (ret && !force_remove)
+ return -EBUSY;
+
+ sysfs_remove_groups(&mdev->dev.kobj, parent->ops->mdev_attr_groups);
+ return 0;
+}
+
+static int mdev_device_remove_cb(struct device *dev, void *data)
+{
+ if (!dev_is_mdev(dev))
+ return 0;
+
+ return mdev_device_remove(dev, data ? *(bool *)data : true);
+}
+
+/*
+ * mdev_register_device : Register a device
+ * @dev: device structure representing parent device.
+ * @ops: Parent device operation structure to be registered.
+ *
+ * Add device to list of registered parent devices.
+ * Returns a negative value on error, otherwise 0.
+ */
+int mdev_register_device(struct device *dev, const struct parent_ops *ops)
+{
+ int ret;
+ struct parent_device *parent;
+
+ /* check for mandatory ops */
+ if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
+ return -EINVAL;
+
+ dev = get_device(dev);
+ if (!dev)
+ return -EINVAL;
+
+ mutex_lock(&parent_list_lock);
+
+ /* Check for duplicate */
+ parent = __find_parent_device(dev);
+ if (parent) {
+ ret = -EEXIST;
+ goto add_dev_err;
+ }
+
+ parent = kzalloc(sizeof(*parent), GFP_KERNEL);
+ if (!parent) {
+ ret = -ENOMEM;
+ goto add_dev_err;
+ }
+
+ kref_init(&parent->ref);
+ mutex_init(&parent->lock);
+
+ parent->dev = dev;
+ parent->ops = ops;
+
+ ret = parent_create_sysfs_files(parent);
+ if (ret) {
+ mutex_unlock(&parent_list_lock);
+ mdev_put_parent(parent);
+ return ret;
+ }
+
+ ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
+ if (ret)
+ dev_warn(dev, "Failed to create compatibility class link\n");
+
+ list_add(&parent->next, &parent_list);
+ mutex_unlock(&parent_list_lock);
+
+ dev_info(dev, "MDEV: Registered\n");
+ return 0;
+
+add_dev_err:
+ mutex_unlock(&parent_list_lock);
+ put_device(dev);
+ return ret;
+}
+EXPORT_SYMBOL(mdev_register_device);
+
+/*
+ * mdev_unregister_device : Unregister a parent device
+ * @dev: device structure representing parent device.
+ *
+ * Remove device from list of registered parent devices. Give a chance to free
+ * existing mediated devices for given device.
+ */
+
+void mdev_unregister_device(struct device *dev)
+{
+ struct parent_device *parent;
+ bool force_remove = true;
+
+ mutex_lock(&parent_list_lock);
+ parent = __find_parent_device(dev);
+
+ if (!parent) {
+ mutex_unlock(&parent_list_lock);
+ return;
+ }
+ dev_info(dev, "MDEV: Unregistering\n");
+
+ list_del(&parent->next);
+ class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
+
+ device_for_each_child(dev, (void *)&force_remove,
+ mdev_device_remove_cb);
+
+ parent_remove_sysfs_files(parent);
+
+ mutex_unlock(&parent_list_lock);
+ mdev_put_parent(parent);
+}
+EXPORT_SYMBOL(mdev_unregister_device);
+
+static void mdev_device_release(struct device *dev)
+{
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ dev_dbg(&mdev->dev, "MDEV: destroying\n");
+ kfree(mdev);
+}
+
+int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
+{
+ int ret;
+ struct mdev_device *mdev;
+ struct parent_device *parent;
+ struct mdev_type *type = to_mdev_type(kobj);
+
+ parent = mdev_get_parent(type->parent);
+ if (!parent)
+ return -EINVAL;
+
+ mutex_lock(&parent->lock);
+
+ /* Check for duplicate */
+ if (mdev_device_exist(parent, uuid)) {
+ ret = -EEXIST;
+ goto create_err;
+ }
+
+ mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
+ if (!mdev) {
+ ret = -ENOMEM;
+ goto create_err;
+ }
+
+ memcpy(&mdev->uuid, &uuid, sizeof(uuid_le));
+ mdev->parent = parent;
+ kref_init(&mdev->ref);
+
+ mdev->dev.parent = dev;
+ mdev->dev.bus = &mdev_bus_type;
+ mdev->dev.release = mdev_device_release;
+ dev_set_name(&mdev->dev, "%pUl", uuid.b);
+
+ ret = device_register(&mdev->dev);
+ if (ret) {
+ put_device(&mdev->dev);
+ goto create_err;
+ }
+
+ ret = mdev_device_create_ops(kobj, mdev);
+ if (ret)
+ goto create_failed;
+
+ ret = mdev_create_sysfs_files(&mdev->dev, type);
+ if (ret) {
+ mdev_device_remove_ops(mdev, true);
+ goto create_failed;
+ }
+
+ mdev->type_kobj = kobj;
+ dev_dbg(&mdev->dev, "MDEV: created\n");
+
+ mutex_unlock(&parent->lock);
+ return ret;
+
+create_failed:
+ device_unregister(&mdev->dev);
+
+create_err:
+ mutex_unlock(&parent->lock);
+ mdev_put_parent(parent);
+ return ret;
+}
+
+int mdev_device_remove(struct device *dev, bool force_remove)
+{
+ struct mdev_device *mdev;
+ struct parent_device *parent;
+ struct mdev_type *type;
+ int ret;
+
+ mdev = to_mdev_device(dev);
+ type = to_mdev_type(mdev->type_kobj);
+ parent = mdev->parent;
+ mutex_lock(&parent->lock);
+
+ ret = mdev_device_remove_ops(mdev, force_remove);
+ if (ret) {
+ mutex_unlock(&parent->lock);
+ return ret;
+ }
+
+ mdev_remove_sysfs_files(dev, type);
+ device_unregister(dev);
+ mutex_unlock(&parent->lock);
+ mdev_put_parent(parent);
+ return ret;
+}
+
+static int __init mdev_init(void)
+{
+ int ret;
+
+ ret = mdev_bus_register();
+ if (ret) {
+ pr_err("Failed to register mdev bus\n");
+ return ret;
+ }
+
+ mdev_bus_compat_class = class_compat_register("mdev_bus");
+ if (!mdev_bus_compat_class) {
+ mdev_bus_unregister();
+ return -ENOMEM;
+ }
+
+ /*
+ * Attempt to load known vfio_mdev. This gives us a working environment
+ * without the user needing to explicitly load vfio_mdev driver.
+ */
+ request_module_nowait("vfio_mdev");
+
+ return ret;
+}
+
+static void __exit mdev_exit(void)
+{
+ class_compat_unregister(mdev_bus_compat_class);
+ mdev_bus_unregister();
+}
+
+module_init(mdev_init)
+module_exit(mdev_exit)
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
new file mode 100644
index 000000000000..0b3250044a80
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_driver.c
@@ -0,0 +1,122 @@
+/*
+ * MDEV driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/iommu.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+static int mdev_attach_iommu(struct mdev_device *mdev)
+{
+ int ret;
+ struct iommu_group *group;
+
+ group = iommu_group_alloc();
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = iommu_group_add_device(group, &mdev->dev);
+ if (ret)
+ goto attach_fail;
+
+ dev_info(&mdev->dev, "MDEV: group_id = %d\n",
+ iommu_group_id(group));
+attach_fail:
+ iommu_group_put(group);
+ return ret;
+}
+
+static void mdev_detach_iommu(struct mdev_device *mdev)
+{
+ iommu_group_remove_device(&mdev->dev);
+ dev_info(&mdev->dev, "MDEV: detaching iommu\n");
+}
+
+static int mdev_probe(struct device *dev)
+{
+ struct mdev_driver *drv = to_mdev_driver(dev->driver);
+ struct mdev_device *mdev = to_mdev_device(dev);
+ int ret;
+
+ ret = mdev_attach_iommu(mdev);
+ if (ret)
+ return ret;
+
+ if (drv && drv->probe)
+ ret = drv->probe(dev);
+
+ if (ret)
+ mdev_detach_iommu(mdev);
+
+ return ret;
+}
+
+static int mdev_remove(struct device *dev)
+{
+ struct mdev_driver *drv = to_mdev_driver(dev->driver);
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ if (drv && drv->remove)
+ drv->remove(dev);
+
+ mdev_detach_iommu(mdev);
+
+ return 0;
+}
+
+struct bus_type mdev_bus_type = {
+ .name = "mdev",
+ .probe = mdev_probe,
+ .remove = mdev_remove,
+};
+EXPORT_SYMBOL_GPL(mdev_bus_type);
+
+/*
+ * mdev_register_driver - register a new MDEV driver
+ * @drv: the driver to register
+ * @owner: module owner of driver to be registered
+ *
+ * Returns a negative value on error, otherwise 0.
+ */
+int mdev_register_driver(struct mdev_driver *drv, struct module *owner)
+{
+ /* initialize common driver fields */
+ drv->driver.name = drv->name;
+ drv->driver.bus = &mdev_bus_type;
+ drv->driver.owner = owner;
+
+ /* register with core */
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL(mdev_register_driver);
+
+/*
+ * mdev_unregister_driver - unregister MDEV driver
+ * @drv: the driver to unregister
+ *
+ */
+void mdev_unregister_driver(struct mdev_driver *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL(mdev_unregister_driver);
+
+int mdev_bus_register(void)
+{
+ return bus_register(&mdev_bus_type);
+}
+
+void mdev_bus_unregister(void)
+{
+ bus_unregister(&mdev_bus_type);
+}
diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
new file mode 100644
index 000000000000..000c93fcfdbd
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_private.h
@@ -0,0 +1,41 @@
+/*
+ * Mediated device interal definitions
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef MDEV_PRIVATE_H
+#define MDEV_PRIVATE_H
+
+int mdev_bus_register(void);
+void mdev_bus_unregister(void);
+
+struct mdev_type {
+ struct kobject kobj;
+ struct kobject *devices_kobj;
+ struct parent_device *parent;
+ struct list_head next;
+ struct attribute_group *group;
+};
+
+#define to_mdev_type_attr(_attr) \
+ container_of(_attr, struct mdev_type_attribute, attr)
+#define to_mdev_type(_kobj) \
+ container_of(_kobj, struct mdev_type, kobj)
+
+int parent_create_sysfs_files(struct parent_device *parent);
+void parent_remove_sysfs_files(struct parent_device *parent);
+
+int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type);
+void mdev_remove_sysfs_files(struct device *dev, struct mdev_type *type);
+
+int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid);
+int mdev_device_remove(struct device *dev, bool force_remove);
+
+#endif /* MDEV_PRIVATE_H */
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
new file mode 100644
index 000000000000..d808a41e4f68
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -0,0 +1,286 @@
+/*
+ * File attributes for Mediated devices
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/sysfs.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+/* Static functions */
+
+static ssize_t mdev_type_attr_show(struct kobject *kobj,
+ struct attribute *__attr, char *buf)
+{
+ struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
+ struct mdev_type *type = to_mdev_type(kobj);
+ ssize_t ret = -EIO;
+
+ if (attr->show)
+ ret = attr->show(kobj, type->parent->dev, buf);
+ return ret;
+}
+
+static ssize_t mdev_type_attr_store(struct kobject *kobj,
+ struct attribute *__attr,
+ const char *buf, size_t count)
+{
+ struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
+ struct mdev_type *type = to_mdev_type(kobj);
+ ssize_t ret = -EIO;
+
+ if (attr->store)
+ ret = attr->store(&type->kobj, type->parent->dev, buf, count);
+ return ret;
+}
+
+static const struct sysfs_ops mdev_type_sysfs_ops = {
+ .show = mdev_type_attr_show,
+ .store = mdev_type_attr_store,
+};
+
+static ssize_t create_store(struct kobject *kobj, struct device *dev,
+ const char *buf, size_t count)
+{
+ char *str;
+ uuid_le uuid;
+ int ret;
+
+ if ((count < UUID_STRING_LEN) || (count > UUID_STRING_LEN + 1))
+ return -EINVAL;
+
+ str = kstrndup(buf, count, GFP_KERNEL);
+ if (!str)
+ return -ENOMEM;
+
+ ret = uuid_le_to_bin(str, &uuid);
+ kfree(str);
+ if (ret)
+ return ret;
+
+ ret = mdev_device_create(kobj, dev, uuid);
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+MDEV_TYPE_ATTR_WO(create);
+
+static void mdev_type_release(struct kobject *kobj)
+{
+ struct mdev_type *type = to_mdev_type(kobj);
+
+ pr_debug("Releasing group %s\n", kobj->name);
+ kfree(type);
+}
+
+static struct kobj_type mdev_type_ktype = {
+ .sysfs_ops = &mdev_type_sysfs_ops,
+ .release = mdev_type_release,
+};
+
+struct mdev_type *add_mdev_supported_type(struct parent_device *parent,
+ struct attribute_group *group)
+{
+ struct mdev_type *type;
+ int ret;
+
+ if (!group->name) {
+ pr_err("%s: Type name empty!\n", __func__);
+ return ERR_PTR(-EINVAL);
+ }
+
+ type = kzalloc(sizeof(*type), GFP_KERNEL);
+ if (!type)
+ return ERR_PTR(-ENOMEM);
+
+ type->kobj.kset = parent->mdev_types_kset;
+
+ ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
+ "%s-%s", dev_driver_string(parent->dev),
+ group->name);
+ if (ret) {
+ kfree(type);
+ return ERR_PTR(ret);
+ }
+
+ ret = sysfs_create_file(&type->kobj, &mdev_type_attr_create.attr);
+ if (ret)
+ goto attr_create_failed;
+
+ type->devices_kobj = kobject_create_and_add("devices", &type->kobj);
+ if (!type->devices_kobj) {
+ ret = -ENOMEM;
+ goto attr_devices_failed;
+ }
+
+ ret = sysfs_create_files(&type->kobj,
+ (const struct attribute **)group->attrs);
+ if (ret) {
+ ret = -ENOMEM;
+ goto attrs_failed;
+ }
+
+ type->group = group;
+ type->parent = parent;
+ return type;
+
+attrs_failed:
+ kobject_put(type->devices_kobj);
+attr_devices_failed:
+ sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
+attr_create_failed:
+ kobject_del(&type->kobj);
+ kobject_put(&type->kobj);
+ return ERR_PTR(ret);
+}
+
+static void remove_mdev_supported_type(struct mdev_type *type)
+{
+ sysfs_remove_files(&type->kobj,
+ (const struct attribute **)type->group->attrs);
+ kobject_put(type->devices_kobj);
+ sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
+ kobject_del(&type->kobj);
+ kobject_put(&type->kobj);
+}
+
+static int add_mdev_supported_type_groups(struct parent_device *parent)
+{
+ int i;
+
+ for (i = 0; parent->ops->supported_type_groups[i]; i++) {
+ struct mdev_type *type;
+
+ type = add_mdev_supported_type(parent,
+ parent->ops->supported_type_groups[i]);
+ if (IS_ERR(type)) {
+ struct mdev_type *ltype, *tmp;
+
+ list_for_each_entry_safe(ltype, tmp, &parent->type_list,
+ next) {
+ list_del(<ype->next);
+ remove_mdev_supported_type(ltype);
+ }
+ return PTR_ERR(type);
+ }
+ list_add(&type->next, &parent->type_list);
+ }
+ return 0;
+}
+
+/* mdev sysfs Functions */
+void parent_remove_sysfs_files(struct parent_device *parent)
+{
+ struct mdev_type *type, *tmp;
+
+ list_for_each_entry_safe(type, tmp, &parent->type_list, next) {
+ list_del(&type->next);
+ remove_mdev_supported_type(type);
+ }
+
+ sysfs_remove_groups(&parent->dev->kobj, parent->ops->dev_attr_groups);
+ kset_unregister(parent->mdev_types_kset);
+}
+
+int parent_create_sysfs_files(struct parent_device *parent)
+{
+ int ret;
+
+ parent->mdev_types_kset = kset_create_and_add("mdev_supported_types",
+ NULL, &parent->dev->kobj);
+
+ if (!parent->mdev_types_kset)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&parent->type_list);
+
+ ret = sysfs_create_groups(&parent->dev->kobj,
+ parent->ops->dev_attr_groups);
+ if (ret)
+ goto create_err;
+
+ ret = add_mdev_supported_type_groups(parent);
+ if (ret)
+ sysfs_remove_groups(&parent->dev->kobj,
+ parent->ops->dev_attr_groups);
+ else
+ return ret;
+
+create_err:
+ kset_unregister(parent->mdev_types_kset);
+ return ret;
+}
+
+static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+
+ if (kstrtoul(buf, 0, &val) < 0)
+ return -EINVAL;
+
+ if (val && device_remove_file_self(dev, attr)) {
+ int ret;
+
+ ret = mdev_device_remove(dev, false);
+ if (ret) {
+ device_create_file(dev, attr);
+ return ret;
+ }
+ }
+
+ return count;
+}
+
+static DEVICE_ATTR_WO(remove);
+
+static const struct attribute *mdev_device_attrs[] = {
+ &dev_attr_remove.attr,
+ NULL,
+};
+
+int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type)
+{
+ int ret;
+
+ ret = sysfs_create_files(&dev->kobj, mdev_device_attrs);
+ if (ret)
+ return ret;
+
+ ret = sysfs_create_link(type->devices_kobj, &dev->kobj, dev_name(dev));
+ if (ret)
+ goto device_link_failed;
+
+ ret = sysfs_create_link(&dev->kobj, &type->kobj, "mdev_type");
+ if (ret)
+ goto type_link_failed;
+
+ return ret;
+
+type_link_failed:
+ sysfs_remove_link(type->devices_kobj, dev_name(dev));
+device_link_failed:
+ sysfs_remove_files(&dev->kobj, mdev_device_attrs);
+ return ret;
+}
+
+void mdev_remove_sysfs_files(struct device *dev, struct mdev_type *type)
+{
+ sysfs_remove_link(&dev->kobj, "mdev_type");
+ sysfs_remove_link(type->devices_kobj, dev_name(dev));
+ sysfs_remove_files(&dev->kobj, mdev_device_attrs);
+}
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
new file mode 100644
index 000000000000..0352febc1944
--- /dev/null
+++ b/include/linux/mdev.h
@@ -0,0 +1,167 @@
+/*
+ * Mediated device definition
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef MDEV_H
+#define MDEV_H
+
+/* Parent Device */
+struct parent_device {
+ struct device *dev;
+ const struct parent_ops *ops;
+
+ /* internal */
+ struct kref ref;
+ struct mutex lock;
+ struct list_head next;
+ struct kset *mdev_types_kset;
+ struct list_head type_list;
+};
+
+/* Mediated device */
+struct mdev_device {
+ struct device dev;
+ struct parent_device *parent;
+ uuid_le uuid;
+ void *driver_data;
+
+ /* internal */
+ struct kref ref;
+ struct list_head next;
+ struct kobject *type_kobj;
+};
+
+
+/**
+ * struct parent_ops - Structure to be registered for each parent device to
+ * register the device to mdev module.
+ *
+ * @owner: The module owner.
+ * @dev_attr_groups: Attributes of the parent device.
+ * @mdev_attr_groups: Attributes of the mediated device.
+ * @supported_type_groups: Attributes to define supported types. It is mandatory
+ * to provide supported types.
+ * @create: Called to allocate basic resources in parent device's
+ * driver for a particular mediated device. It is
+ * mandatory to provide create ops.
+ * @kobj: kobject of type for which 'create' is called.
+ * @mdev: mdev_device structure on of mediated device
+ * that is being created
+ * Returns integer: success (0) or error (< 0)
+ * @remove: Called to free resources in parent device's driver for a
+ * a mediated device. It is mandatory to provide 'remove'
+ * ops.
+ * @mdev: mdev_device device structure which is being
+ * destroyed
+ * Returns integer: success (0) or error (< 0)
+ * @open: Open mediated device.
+ * @mdev: mediated device.
+ * Returns integer: success (0) or error (< 0)
+ * @release: release mediated device
+ * @mdev: mediated device.
+ * @read: Read emulation callback
+ * @mdev: mediated device structure
+ * @buf: read buffer
+ * @count: number of bytes to read
+ * @ppos: address.
+ * Retuns number on bytes read on success or error.
+ * @write: Write emulation callback
+ * @mdev: mediated device structure
+ * @buf: write buffer
+ * @count: number of bytes to be written
+ * @ppos: address.
+ * Retuns number on bytes written on success or error.
+ * @ioctl: IOCTL callback
+ * @mdev: mediated device structure
+ * @cmd: mediated device structure
+ * @arg: mediated device structure
+ * @mmap: mmap callback
+ * Parent device that support mediated device should be registered with mdev
+ * module with parent_ops structure.
+ **/
+
+struct parent_ops {
+ struct module *owner;
+ const struct attribute_group **dev_attr_groups;
+ const struct attribute_group **mdev_attr_groups;
+ struct attribute_group **supported_type_groups;
+
+ int (*create)(struct kobject *kobj, struct mdev_device *mdev);
+ int (*remove)(struct mdev_device *mdev);
+ int (*open)(struct mdev_device *mdev);
+ void (*release)(struct mdev_device *mdev);
+ ssize_t (*read)(struct mdev_device *mdev, char __user *buf,
+ size_t count, loff_t *ppos);
+ ssize_t (*write)(struct mdev_device *mdev, const char __user *buf,
+ size_t count, loff_t *ppos);
+ ssize_t (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
+ unsigned long arg);
+ int (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
+};
+
+/* interface for exporting mdev supported type attributes */
+struct mdev_type_attribute {
+ struct attribute attr;
+ ssize_t (*show)(struct kobject *kobj, struct device *dev, char *buf);
+ ssize_t (*store)(struct kobject *kobj, struct device *dev,
+ const char *buf, size_t count);
+};
+
+#define MDEV_TYPE_ATTR(_name, _mode, _show, _store) \
+struct mdev_type_attribute mdev_type_attr_##_name = \
+ __ATTR(_name, _mode, _show, _store)
+#define MDEV_TYPE_ATTR_RW(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
+#define MDEV_TYPE_ATTR_RO(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
+#define MDEV_TYPE_ATTR_WO(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
+
+/**
+ * struct mdev_driver - Mediated device driver
+ * @name: driver name
+ * @probe: called when new device created
+ * @remove: called when device removed
+ * @driver: device driver structure
+ *
+ **/
+struct mdev_driver {
+ const char *name;
+ int (*probe)(struct device *dev);
+ void (*remove)(struct device *dev);
+ struct device_driver driver;
+};
+
+#define to_mdev_driver(drv) container_of(drv, struct mdev_driver, driver)
+#define to_mdev_device(dev) container_of(dev, struct mdev_device, dev)
+
+static inline void *mdev_get_drvdata(struct mdev_device *mdev)
+{
+ return mdev->driver_data;
+}
+
+static inline void mdev_set_drvdata(struct mdev_device *mdev, void *data)
+{
+ mdev->driver_data = data;
+}
+
+extern struct bus_type mdev_bus_type;
+
+#define dev_is_mdev(d) ((d)->bus == &mdev_bus_type)
+
+extern int mdev_register_device(struct device *dev,
+ const struct parent_ops *ops);
+extern void mdev_unregister_device(struct device *dev);
+
+extern int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
+extern void mdev_unregister_driver(struct mdev_driver *drv);
+
+#endif /* MDEV_H */
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Design for Mediated Device Driver:
Main purpose of this driver is to provide a common interface for mediated
device management that can be used by different drivers of different
devices.
This module provides a generic interface to create the device, add it to
mediated bus, add device to IOMMU group and then add it to vfio group.
Below is the high Level block diagram, with Nvidia, Intel and IBM devices
as example, since these are the devices which are going to actively use
this module as of now.
+---------------+
| |
| +-----------+ | mdev_register_driver() +--------------+
| | | +<------------------------+ __init() |
| | mdev | | | |
| | bus | +------------------------>+ |<-> VFIO user
| | driver | | probe()/remove() | vfio_mdev.ko | APIs
| | | | | |
| +-----------+ | +--------------+
| |
| MDEV CORE |
| MODULE |
| mdev.ko |
| +-----------+ | mdev_register_device() +--------------+
| | | +<------------------------+ |
| | | | | nvidia.ko |<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| | Physical | |
| | device | | mdev_register_device() +--------------+
| | interface | |<------------------------+ |
| | | | | i915.ko |<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| | | |
| | | | mdev_register_device() +--------------+
| | | +<------------------------+ |
| | | | | ccw_device.ko|<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| +-----------+ |
+---------------+
Core driver provides two types of registration interfaces:
1. Registration interface for mediated bus driver:
/**
* struct mdev_driver - Mediated device's driver
* @name: driver name
* @probe: called when new device created
* @remove:called when device removed
* @driver:device driver structure
*
**/
struct mdev_driver {
const char *name;
int (*probe) (struct device *dev);
void (*remove) (struct device *dev);
struct device_driver driver;
};
Mediated bus driver for mdev device should use this interface to register
and unregister with core driver respectively:
int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
void mdev_unregister_driver(struct mdev_driver *drv);
Mediated bus driver is responsible to add/delete mediated devices to/from
VFIO group when devices are bound and unbound to the driver.
2. Physical device driver interface
This interface provides vendor driver the set APIs to manage physical
device related work in its driver. APIs are :
* dev_attr_groups: attributes of the parent device.
* mdev_attr_groups: attributes of the mediated device.
* supported_type_groups: attributes to define supported type. This is
mandatory field.
* create: to allocate basic resources in vendor driver for a mediated
device. This is mandatory to be provided by vendor driver.
* remove: to free resources in vendor driver when mediated device is
destroyed. This is mandatory to be provided by vendor driver.
* open: open callback of mediated device
* release: release callback of mediated device
* read : read emulation callback.
* write: write emulation callback.
* mmap: mmap emulation callback.
* ioctl: ioctl callback.
Drivers should use these interfaces to register and unregister device to
mdev core driver respectively:
extern int mdev_register_device(struct device *dev,
const struct parent_ops *ops);
extern void mdev_unregister_device(struct device *dev);
There are no locks to serialize above callbacks in mdev driver and
vfio_mdev driver. If required, vendor driver can have locks to serialize
above APIs in their driver.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I73a5084574270b14541c529461ea2f03c292d510
---
drivers/vfio/Kconfig | 1 +
drivers/vfio/Makefile | 1 +
drivers/vfio/mdev/Kconfig | 10 +
drivers/vfio/mdev/Makefile | 4 +
drivers/vfio/mdev/mdev_core.c | 384 +++++++++++++++++++++++++++++++++++++++
drivers/vfio/mdev/mdev_driver.c | 122 +++++++++++++
drivers/vfio/mdev/mdev_private.h | 41 +++++
drivers/vfio/mdev/mdev_sysfs.c | 286 +++++++++++++++++++++++++++++
include/linux/mdev.h | 167 +++++++++++++++++
9 files changed, 1016 insertions(+)
create mode 100644 drivers/vfio/mdev/Kconfig
create mode 100644 drivers/vfio/mdev/Makefile
create mode 100644 drivers/vfio/mdev/mdev_core.c
create mode 100644 drivers/vfio/mdev/mdev_driver.c
create mode 100644 drivers/vfio/mdev/mdev_private.h
create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
create mode 100644 include/linux/mdev.h
diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
index da6e2ce77495..23eced02aaf6 100644
--- a/drivers/vfio/Kconfig
+++ b/drivers/vfio/Kconfig
@@ -48,4 +48,5 @@ menuconfig VFIO_NOIOMMU
source "drivers/vfio/pci/Kconfig"
source "drivers/vfio/platform/Kconfig"
+source "drivers/vfio/mdev/Kconfig"
source "virt/lib/Kconfig"
diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
index 7b8a31f63fea..4a23c13b6be4 100644
--- a/drivers/vfio/Makefile
+++ b/drivers/vfio/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
obj-$(CONFIG_VFIO_SPAPR_EEH) += vfio_spapr_eeh.o
obj-$(CONFIG_VFIO_PCI) += pci/
obj-$(CONFIG_VFIO_PLATFORM) += platform/
+obj-$(CONFIG_VFIO_MDEV) += mdev/
diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
new file mode 100644
index 000000000000..303c14ce2847
--- /dev/null
+++ b/drivers/vfio/mdev/Kconfig
@@ -0,0 +1,10 @@
+
+config VFIO_MDEV
+ tristate "Mediated device driver framework"
+ depends on VFIO
+ default n
+ help
+ Provides a framework to virtualize devices.
+ See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
+
+ If you don't know what do here, say N.
diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
new file mode 100644
index 000000000000..31bc04801d94
--- /dev/null
+++ b/drivers/vfio/mdev/Makefile
@@ -0,0 +1,4 @@
+
+mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
+
+obj-$(CONFIG_VFIO_MDEV) += mdev.o
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
new file mode 100644
index 000000000000..9d8fa5c91c2e
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -0,0 +1,384 @@
+/*
+ * Mediated device Core Driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+#include <linux/sysfs.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "NVIDIA Corporation"
+#define DRIVER_DESC "Mediated device Core Driver"
+
+static LIST_HEAD(parent_list);
+static DEFINE_MUTEX(parent_list_lock);
+static struct class_compat *mdev_bus_compat_class;
+
+static int _find_mdev_device(struct device *dev, void *data)
+{
+ struct mdev_device *mdev;
+
+ if (!dev_is_mdev(dev))
+ return 0;
+
+ mdev = to_mdev_device(dev);
+
+ if (uuid_le_cmp(mdev->uuid, *(uuid_le *)data) == 0)
+ return 1;
+
+ return 0;
+}
+
+static bool mdev_device_exist(struct parent_device *parent, uuid_le uuid)
+{
+ struct device *dev;
+
+ dev = device_find_child(parent->dev, &uuid, _find_mdev_device);
+ if (dev) {
+ put_device(dev);
+ return true;
+ }
+
+ return false;
+}
+
+/* Should be called holding parent_list_lock */
+static struct parent_device *__find_parent_device(struct device *dev)
+{
+ struct parent_device *parent;
+
+ list_for_each_entry(parent, &parent_list, next) {
+ if (parent->dev == dev)
+ return parent;
+ }
+ return NULL;
+}
+
+static void mdev_release_parent(struct kref *kref)
+{
+ struct parent_device *parent = container_of(kref, struct parent_device,
+ ref);
+ struct device *dev = parent->dev;
+
+ kfree(parent);
+ put_device(dev);
+}
+
+static
+inline struct parent_device *mdev_get_parent(struct parent_device *parent)
+{
+ if (parent)
+ kref_get(&parent->ref);
+
+ return parent;
+}
+
+static inline void mdev_put_parent(struct parent_device *parent)
+{
+ if (parent)
+ kref_put(&parent->ref, mdev_release_parent);
+}
+
+static int mdev_device_create_ops(struct kobject *kobj,
+ struct mdev_device *mdev)
+{
+ struct parent_device *parent = mdev->parent;
+ int ret;
+
+ ret = parent->ops->create(kobj, mdev);
+ if (ret)
+ return ret;
+
+ ret = sysfs_create_groups(&mdev->dev.kobj,
+ parent->ops->mdev_attr_groups);
+ if (ret)
+ parent->ops->remove(mdev);
+
+ return ret;
+}
+
+/*
+ * mdev_device_remove_ops gets called from sysfs's 'remove' and when parent
+ * device is being unregistered from mdev device framework.
+ * - 'force_remove' is set to 'false' when called from sysfs's 'remove' which
+ * indicates that if the mdev device is active, used by VMM or userspace
+ * application, vendor driver could return error then don't remove the device.
+ * - 'force_remove' is set to 'true' when called from mdev_unregister_device()
+ * which indicate that parent device is being removed from mdev device
+ * framework so remove mdev device forcefully.
+ */
+static int mdev_device_remove_ops(struct mdev_device *mdev, bool force_remove)
+{
+ struct parent_device *parent = mdev->parent;
+ int ret;
+
+ /*
+ * Vendor driver can return error if VMM or userspace application is
+ * using this mdev device.
+ */
+ ret = parent->ops->remove(mdev);
+ if (ret && !force_remove)
+ return -EBUSY;
+
+ sysfs_remove_groups(&mdev->dev.kobj, parent->ops->mdev_attr_groups);
+ return 0;
+}
+
+static int mdev_device_remove_cb(struct device *dev, void *data)
+{
+ if (!dev_is_mdev(dev))
+ return 0;
+
+ return mdev_device_remove(dev, data ? *(bool *)data : true);
+}
+
+/*
+ * mdev_register_device : Register a device
+ * @dev: device structure representing parent device.
+ * @ops: Parent device operation structure to be registered.
+ *
+ * Add device to list of registered parent devices.
+ * Returns a negative value on error, otherwise 0.
+ */
+int mdev_register_device(struct device *dev, const struct parent_ops *ops)
+{
+ int ret;
+ struct parent_device *parent;
+
+ /* check for mandatory ops */
+ if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
+ return -EINVAL;
+
+ dev = get_device(dev);
+ if (!dev)
+ return -EINVAL;
+
+ mutex_lock(&parent_list_lock);
+
+ /* Check for duplicate */
+ parent = __find_parent_device(dev);
+ if (parent) {
+ ret = -EEXIST;
+ goto add_dev_err;
+ }
+
+ parent = kzalloc(sizeof(*parent), GFP_KERNEL);
+ if (!parent) {
+ ret = -ENOMEM;
+ goto add_dev_err;
+ }
+
+ kref_init(&parent->ref);
+ mutex_init(&parent->lock);
+
+ parent->dev = dev;
+ parent->ops = ops;
+
+ ret = parent_create_sysfs_files(parent);
+ if (ret) {
+ mutex_unlock(&parent_list_lock);
+ mdev_put_parent(parent);
+ return ret;
+ }
+
+ ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
+ if (ret)
+ dev_warn(dev, "Failed to create compatibility class link\n");
+
+ list_add(&parent->next, &parent_list);
+ mutex_unlock(&parent_list_lock);
+
+ dev_info(dev, "MDEV: Registered\n");
+ return 0;
+
+add_dev_err:
+ mutex_unlock(&parent_list_lock);
+ put_device(dev);
+ return ret;
+}
+EXPORT_SYMBOL(mdev_register_device);
+
+/*
+ * mdev_unregister_device : Unregister a parent device
+ * @dev: device structure representing parent device.
+ *
+ * Remove device from list of registered parent devices. Give a chance to free
+ * existing mediated devices for given device.
+ */
+
+void mdev_unregister_device(struct device *dev)
+{
+ struct parent_device *parent;
+ bool force_remove = true;
+
+ mutex_lock(&parent_list_lock);
+ parent = __find_parent_device(dev);
+
+ if (!parent) {
+ mutex_unlock(&parent_list_lock);
+ return;
+ }
+ dev_info(dev, "MDEV: Unregistering\n");
+
+ list_del(&parent->next);
+ class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
+
+ device_for_each_child(dev, (void *)&force_remove,
+ mdev_device_remove_cb);
+
+ parent_remove_sysfs_files(parent);
+
+ mutex_unlock(&parent_list_lock);
+ mdev_put_parent(parent);
+}
+EXPORT_SYMBOL(mdev_unregister_device);
+
+static void mdev_device_release(struct device *dev)
+{
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ dev_dbg(&mdev->dev, "MDEV: destroying\n");
+ kfree(mdev);
+}
+
+int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
+{
+ int ret;
+ struct mdev_device *mdev;
+ struct parent_device *parent;
+ struct mdev_type *type = to_mdev_type(kobj);
+
+ parent = mdev_get_parent(type->parent);
+ if (!parent)
+ return -EINVAL;
+
+ mutex_lock(&parent->lock);
+
+ /* Check for duplicate */
+ if (mdev_device_exist(parent, uuid)) {
+ ret = -EEXIST;
+ goto create_err;
+ }
+
+ mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
+ if (!mdev) {
+ ret = -ENOMEM;
+ goto create_err;
+ }
+
+ memcpy(&mdev->uuid, &uuid, sizeof(uuid_le));
+ mdev->parent = parent;
+ kref_init(&mdev->ref);
+
+ mdev->dev.parent = dev;
+ mdev->dev.bus = &mdev_bus_type;
+ mdev->dev.release = mdev_device_release;
+ dev_set_name(&mdev->dev, "%pUl", uuid.b);
+
+ ret = device_register(&mdev->dev);
+ if (ret) {
+ put_device(&mdev->dev);
+ goto create_err;
+ }
+
+ ret = mdev_device_create_ops(kobj, mdev);
+ if (ret)
+ goto create_failed;
+
+ ret = mdev_create_sysfs_files(&mdev->dev, type);
+ if (ret) {
+ mdev_device_remove_ops(mdev, true);
+ goto create_failed;
+ }
+
+ mdev->type_kobj = kobj;
+ dev_dbg(&mdev->dev, "MDEV: created\n");
+
+ mutex_unlock(&parent->lock);
+ return ret;
+
+create_failed:
+ device_unregister(&mdev->dev);
+
+create_err:
+ mutex_unlock(&parent->lock);
+ mdev_put_parent(parent);
+ return ret;
+}
+
+int mdev_device_remove(struct device *dev, bool force_remove)
+{
+ struct mdev_device *mdev;
+ struct parent_device *parent;
+ struct mdev_type *type;
+ int ret;
+
+ mdev = to_mdev_device(dev);
+ type = to_mdev_type(mdev->type_kobj);
+ parent = mdev->parent;
+ mutex_lock(&parent->lock);
+
+ ret = mdev_device_remove_ops(mdev, force_remove);
+ if (ret) {
+ mutex_unlock(&parent->lock);
+ return ret;
+ }
+
+ mdev_remove_sysfs_files(dev, type);
+ device_unregister(dev);
+ mutex_unlock(&parent->lock);
+ mdev_put_parent(parent);
+ return ret;
+}
+
+static int __init mdev_init(void)
+{
+ int ret;
+
+ ret = mdev_bus_register();
+ if (ret) {
+ pr_err("Failed to register mdev bus\n");
+ return ret;
+ }
+
+ mdev_bus_compat_class = class_compat_register("mdev_bus");
+ if (!mdev_bus_compat_class) {
+ mdev_bus_unregister();
+ return -ENOMEM;
+ }
+
+ /*
+ * Attempt to load known vfio_mdev. This gives us a working environment
+ * without the user needing to explicitly load vfio_mdev driver.
+ */
+ request_module_nowait("vfio_mdev");
+
+ return ret;
+}
+
+static void __exit mdev_exit(void)
+{
+ class_compat_unregister(mdev_bus_compat_class);
+ mdev_bus_unregister();
+}
+
+module_init(mdev_init)
+module_exit(mdev_exit)
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
new file mode 100644
index 000000000000..0b3250044a80
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_driver.c
@@ -0,0 +1,122 @@
+/*
+ * MDEV driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/iommu.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+static int mdev_attach_iommu(struct mdev_device *mdev)
+{
+ int ret;
+ struct iommu_group *group;
+
+ group = iommu_group_alloc();
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = iommu_group_add_device(group, &mdev->dev);
+ if (ret)
+ goto attach_fail;
+
+ dev_info(&mdev->dev, "MDEV: group_id = %d\n",
+ iommu_group_id(group));
+attach_fail:
+ iommu_group_put(group);
+ return ret;
+}
+
+static void mdev_detach_iommu(struct mdev_device *mdev)
+{
+ iommu_group_remove_device(&mdev->dev);
+ dev_info(&mdev->dev, "MDEV: detaching iommu\n");
+}
+
+static int mdev_probe(struct device *dev)
+{
+ struct mdev_driver *drv = to_mdev_driver(dev->driver);
+ struct mdev_device *mdev = to_mdev_device(dev);
+ int ret;
+
+ ret = mdev_attach_iommu(mdev);
+ if (ret)
+ return ret;
+
+ if (drv && drv->probe)
+ ret = drv->probe(dev);
+
+ if (ret)
+ mdev_detach_iommu(mdev);
+
+ return ret;
+}
+
+static int mdev_remove(struct device *dev)
+{
+ struct mdev_driver *drv = to_mdev_driver(dev->driver);
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ if (drv && drv->remove)
+ drv->remove(dev);
+
+ mdev_detach_iommu(mdev);
+
+ return 0;
+}
+
+struct bus_type mdev_bus_type = {
+ .name = "mdev",
+ .probe = mdev_probe,
+ .remove = mdev_remove,
+};
+EXPORT_SYMBOL_GPL(mdev_bus_type);
+
+/*
+ * mdev_register_driver - register a new MDEV driver
+ * @drv: the driver to register
+ * @owner: module owner of driver to be registered
+ *
+ * Returns a negative value on error, otherwise 0.
+ */
+int mdev_register_driver(struct mdev_driver *drv, struct module *owner)
+{
+ /* initialize common driver fields */
+ drv->driver.name = drv->name;
+ drv->driver.bus = &mdev_bus_type;
+ drv->driver.owner = owner;
+
+ /* register with core */
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL(mdev_register_driver);
+
+/*
+ * mdev_unregister_driver - unregister MDEV driver
+ * @drv: the driver to unregister
+ *
+ */
+void mdev_unregister_driver(struct mdev_driver *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL(mdev_unregister_driver);
+
+int mdev_bus_register(void)
+{
+ return bus_register(&mdev_bus_type);
+}
+
+void mdev_bus_unregister(void)
+{
+ bus_unregister(&mdev_bus_type);
+}
diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
new file mode 100644
index 000000000000..000c93fcfdbd
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_private.h
@@ -0,0 +1,41 @@
+/*
+ * Mediated device interal definitions
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef MDEV_PRIVATE_H
+#define MDEV_PRIVATE_H
+
+int mdev_bus_register(void);
+void mdev_bus_unregister(void);
+
+struct mdev_type {
+ struct kobject kobj;
+ struct kobject *devices_kobj;
+ struct parent_device *parent;
+ struct list_head next;
+ struct attribute_group *group;
+};
+
+#define to_mdev_type_attr(_attr) \
+ container_of(_attr, struct mdev_type_attribute, attr)
+#define to_mdev_type(_kobj) \
+ container_of(_kobj, struct mdev_type, kobj)
+
+int parent_create_sysfs_files(struct parent_device *parent);
+void parent_remove_sysfs_files(struct parent_device *parent);
+
+int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type);
+void mdev_remove_sysfs_files(struct device *dev, struct mdev_type *type);
+
+int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid);
+int mdev_device_remove(struct device *dev, bool force_remove);
+
+#endif /* MDEV_PRIVATE_H */
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
new file mode 100644
index 000000000000..d808a41e4f68
--- /dev/null
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -0,0 +1,286 @@
+/*
+ * File attributes for Mediated devices
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/sysfs.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/uuid.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+/* Static functions */
+
+static ssize_t mdev_type_attr_show(struct kobject *kobj,
+ struct attribute *__attr, char *buf)
+{
+ struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
+ struct mdev_type *type = to_mdev_type(kobj);
+ ssize_t ret = -EIO;
+
+ if (attr->show)
+ ret = attr->show(kobj, type->parent->dev, buf);
+ return ret;
+}
+
+static ssize_t mdev_type_attr_store(struct kobject *kobj,
+ struct attribute *__attr,
+ const char *buf, size_t count)
+{
+ struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
+ struct mdev_type *type = to_mdev_type(kobj);
+ ssize_t ret = -EIO;
+
+ if (attr->store)
+ ret = attr->store(&type->kobj, type->parent->dev, buf, count);
+ return ret;
+}
+
+static const struct sysfs_ops mdev_type_sysfs_ops = {
+ .show = mdev_type_attr_show,
+ .store = mdev_type_attr_store,
+};
+
+static ssize_t create_store(struct kobject *kobj, struct device *dev,
+ const char *buf, size_t count)
+{
+ char *str;
+ uuid_le uuid;
+ int ret;
+
+ if ((count < UUID_STRING_LEN) || (count > UUID_STRING_LEN + 1))
+ return -EINVAL;
+
+ str = kstrndup(buf, count, GFP_KERNEL);
+ if (!str)
+ return -ENOMEM;
+
+ ret = uuid_le_to_bin(str, &uuid);
+ kfree(str);
+ if (ret)
+ return ret;
+
+ ret = mdev_device_create(kobj, dev, uuid);
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+MDEV_TYPE_ATTR_WO(create);
+
+static void mdev_type_release(struct kobject *kobj)
+{
+ struct mdev_type *type = to_mdev_type(kobj);
+
+ pr_debug("Releasing group %s\n", kobj->name);
+ kfree(type);
+}
+
+static struct kobj_type mdev_type_ktype = {
+ .sysfs_ops = &mdev_type_sysfs_ops,
+ .release = mdev_type_release,
+};
+
+struct mdev_type *add_mdev_supported_type(struct parent_device *parent,
+ struct attribute_group *group)
+{
+ struct mdev_type *type;
+ int ret;
+
+ if (!group->name) {
+ pr_err("%s: Type name empty!\n", __func__);
+ return ERR_PTR(-EINVAL);
+ }
+
+ type = kzalloc(sizeof(*type), GFP_KERNEL);
+ if (!type)
+ return ERR_PTR(-ENOMEM);
+
+ type->kobj.kset = parent->mdev_types_kset;
+
+ ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
+ "%s-%s", dev_driver_string(parent->dev),
+ group->name);
+ if (ret) {
+ kfree(type);
+ return ERR_PTR(ret);
+ }
+
+ ret = sysfs_create_file(&type->kobj, &mdev_type_attr_create.attr);
+ if (ret)
+ goto attr_create_failed;
+
+ type->devices_kobj = kobject_create_and_add("devices", &type->kobj);
+ if (!type->devices_kobj) {
+ ret = -ENOMEM;
+ goto attr_devices_failed;
+ }
+
+ ret = sysfs_create_files(&type->kobj,
+ (const struct attribute **)group->attrs);
+ if (ret) {
+ ret = -ENOMEM;
+ goto attrs_failed;
+ }
+
+ type->group = group;
+ type->parent = parent;
+ return type;
+
+attrs_failed:
+ kobject_put(type->devices_kobj);
+attr_devices_failed:
+ sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
+attr_create_failed:
+ kobject_del(&type->kobj);
+ kobject_put(&type->kobj);
+ return ERR_PTR(ret);
+}
+
+static void remove_mdev_supported_type(struct mdev_type *type)
+{
+ sysfs_remove_files(&type->kobj,
+ (const struct attribute **)type->group->attrs);
+ kobject_put(type->devices_kobj);
+ sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
+ kobject_del(&type->kobj);
+ kobject_put(&type->kobj);
+}
+
+static int add_mdev_supported_type_groups(struct parent_device *parent)
+{
+ int i;
+
+ for (i = 0; parent->ops->supported_type_groups[i]; i++) {
+ struct mdev_type *type;
+
+ type = add_mdev_supported_type(parent,
+ parent->ops->supported_type_groups[i]);
+ if (IS_ERR(type)) {
+ struct mdev_type *ltype, *tmp;
+
+ list_for_each_entry_safe(ltype, tmp, &parent->type_list,
+ next) {
+ list_del(<ype->next);
+ remove_mdev_supported_type(ltype);
+ }
+ return PTR_ERR(type);
+ }
+ list_add(&type->next, &parent->type_list);
+ }
+ return 0;
+}
+
+/* mdev sysfs Functions */
+void parent_remove_sysfs_files(struct parent_device *parent)
+{
+ struct mdev_type *type, *tmp;
+
+ list_for_each_entry_safe(type, tmp, &parent->type_list, next) {
+ list_del(&type->next);
+ remove_mdev_supported_type(type);
+ }
+
+ sysfs_remove_groups(&parent->dev->kobj, parent->ops->dev_attr_groups);
+ kset_unregister(parent->mdev_types_kset);
+}
+
+int parent_create_sysfs_files(struct parent_device *parent)
+{
+ int ret;
+
+ parent->mdev_types_kset = kset_create_and_add("mdev_supported_types",
+ NULL, &parent->dev->kobj);
+
+ if (!parent->mdev_types_kset)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&parent->type_list);
+
+ ret = sysfs_create_groups(&parent->dev->kobj,
+ parent->ops->dev_attr_groups);
+ if (ret)
+ goto create_err;
+
+ ret = add_mdev_supported_type_groups(parent);
+ if (ret)
+ sysfs_remove_groups(&parent->dev->kobj,
+ parent->ops->dev_attr_groups);
+ else
+ return ret;
+
+create_err:
+ kset_unregister(parent->mdev_types_kset);
+ return ret;
+}
+
+static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+
+ if (kstrtoul(buf, 0, &val) < 0)
+ return -EINVAL;
+
+ if (val && device_remove_file_self(dev, attr)) {
+ int ret;
+
+ ret = mdev_device_remove(dev, false);
+ if (ret) {
+ device_create_file(dev, attr);
+ return ret;
+ }
+ }
+
+ return count;
+}
+
+static DEVICE_ATTR_WO(remove);
+
+static const struct attribute *mdev_device_attrs[] = {
+ &dev_attr_remove.attr,
+ NULL,
+};
+
+int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type)
+{
+ int ret;
+
+ ret = sysfs_create_files(&dev->kobj, mdev_device_attrs);
+ if (ret)
+ return ret;
+
+ ret = sysfs_create_link(type->devices_kobj, &dev->kobj, dev_name(dev));
+ if (ret)
+ goto device_link_failed;
+
+ ret = sysfs_create_link(&dev->kobj, &type->kobj, "mdev_type");
+ if (ret)
+ goto type_link_failed;
+
+ return ret;
+
+type_link_failed:
+ sysfs_remove_link(type->devices_kobj, dev_name(dev));
+device_link_failed:
+ sysfs_remove_files(&dev->kobj, mdev_device_attrs);
+ return ret;
+}
+
+void mdev_remove_sysfs_files(struct device *dev, struct mdev_type *type)
+{
+ sysfs_remove_link(&dev->kobj, "mdev_type");
+ sysfs_remove_link(type->devices_kobj, dev_name(dev));
+ sysfs_remove_files(&dev->kobj, mdev_device_attrs);
+}
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
new file mode 100644
index 000000000000..0352febc1944
--- /dev/null
+++ b/include/linux/mdev.h
@@ -0,0 +1,167 @@
+/*
+ * Mediated device definition
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef MDEV_H
+#define MDEV_H
+
+/* Parent Device */
+struct parent_device {
+ struct device *dev;
+ const struct parent_ops *ops;
+
+ /* internal */
+ struct kref ref;
+ struct mutex lock;
+ struct list_head next;
+ struct kset *mdev_types_kset;
+ struct list_head type_list;
+};
+
+/* Mediated device */
+struct mdev_device {
+ struct device dev;
+ struct parent_device *parent;
+ uuid_le uuid;
+ void *driver_data;
+
+ /* internal */
+ struct kref ref;
+ struct list_head next;
+ struct kobject *type_kobj;
+};
+
+
+/**
+ * struct parent_ops - Structure to be registered for each parent device to
+ * register the device to mdev module.
+ *
+ * @owner: The module owner.
+ * @dev_attr_groups: Attributes of the parent device.
+ * @mdev_attr_groups: Attributes of the mediated device.
+ * @supported_type_groups: Attributes to define supported types. It is mandatory
+ * to provide supported types.
+ * @create: Called to allocate basic resources in parent device's
+ * driver for a particular mediated device. It is
+ * mandatory to provide create ops.
+ * @kobj: kobject of type for which 'create' is called.
+ * @mdev: mdev_device structure on of mediated device
+ * that is being created
+ * Returns integer: success (0) or error (< 0)
+ * @remove: Called to free resources in parent device's driver for a
+ * a mediated device. It is mandatory to provide 'remove'
+ * ops.
+ * @mdev: mdev_device device structure which is being
+ * destroyed
+ * Returns integer: success (0) or error (< 0)
+ * @open: Open mediated device.
+ * @mdev: mediated device.
+ * Returns integer: success (0) or error (< 0)
+ * @release: release mediated device
+ * @mdev: mediated device.
+ * @read: Read emulation callback
+ * @mdev: mediated device structure
+ * @buf: read buffer
+ * @count: number of bytes to read
+ * @ppos: address.
+ * Retuns number on bytes read on success or error.
+ * @write: Write emulation callback
+ * @mdev: mediated device structure
+ * @buf: write buffer
+ * @count: number of bytes to be written
+ * @ppos: address.
+ * Retuns number on bytes written on success or error.
+ * @ioctl: IOCTL callback
+ * @mdev: mediated device structure
+ * @cmd: mediated device structure
+ * @arg: mediated device structure
+ * @mmap: mmap callback
+ * Parent device that support mediated device should be registered with mdev
+ * module with parent_ops structure.
+ **/
+
+struct parent_ops {
+ struct module *owner;
+ const struct attribute_group **dev_attr_groups;
+ const struct attribute_group **mdev_attr_groups;
+ struct attribute_group **supported_type_groups;
+
+ int (*create)(struct kobject *kobj, struct mdev_device *mdev);
+ int (*remove)(struct mdev_device *mdev);
+ int (*open)(struct mdev_device *mdev);
+ void (*release)(struct mdev_device *mdev);
+ ssize_t (*read)(struct mdev_device *mdev, char __user *buf,
+ size_t count, loff_t *ppos);
+ ssize_t (*write)(struct mdev_device *mdev, const char __user *buf,
+ size_t count, loff_t *ppos);
+ ssize_t (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
+ unsigned long arg);
+ int (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
+};
+
+/* interface for exporting mdev supported type attributes */
+struct mdev_type_attribute {
+ struct attribute attr;
+ ssize_t (*show)(struct kobject *kobj, struct device *dev, char *buf);
+ ssize_t (*store)(struct kobject *kobj, struct device *dev,
+ const char *buf, size_t count);
+};
+
+#define MDEV_TYPE_ATTR(_name, _mode, _show, _store) \
+struct mdev_type_attribute mdev_type_attr_##_name = \
+ __ATTR(_name, _mode, _show, _store)
+#define MDEV_TYPE_ATTR_RW(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
+#define MDEV_TYPE_ATTR_RO(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
+#define MDEV_TYPE_ATTR_WO(_name) \
+ struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
+
+/**
+ * struct mdev_driver - Mediated device driver
+ * @name: driver name
+ * @probe: called when new device created
+ * @remove: called when device removed
+ * @driver: device driver structure
+ *
+ **/
+struct mdev_driver {
+ const char *name;
+ int (*probe)(struct device *dev);
+ void (*remove)(struct device *dev);
+ struct device_driver driver;
+};
+
+#define to_mdev_driver(drv) container_of(drv, struct mdev_driver, driver)
+#define to_mdev_device(dev) container_of(dev, struct mdev_device, dev)
+
+static inline void *mdev_get_drvdata(struct mdev_device *mdev)
+{
+ return mdev->driver_data;
+}
+
+static inline void mdev_set_drvdata(struct mdev_device *mdev, void *data)
+{
+ mdev->driver_data = data;
+}
+
+extern struct bus_type mdev_bus_type;
+
+#define dev_is_mdev(d) ((d)->bus == &mdev_bus_type)
+
+extern int mdev_register_device(struct device *dev,
+ const struct parent_ops *ops);
+extern void mdev_unregister_device(struct device *dev);
+
+extern int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
+extern void mdev_unregister_driver(struct mdev_driver *drv);
+
+#endif /* MDEV_H */
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 02/19] vfio: VFIO based driver for Mediated devices
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
(?)
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
vfio_mdev driver registers with mdev core driver.
mdev core driver creates mediated device and calls probe routine of
vfio_mdev driver for each device.
Probe routine of vfio_mdev driver adds mediated device to VFIO core module
This driver forms a shim layer that pass through VFIO devices operations
to vendor driver for mediated devices.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
---
drivers/vfio/mdev/Kconfig | 7 ++
drivers/vfio/mdev/Makefile | 1 +
drivers/vfio/mdev/vfio_mdev.c | 148 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 156 insertions(+)
create mode 100644 drivers/vfio/mdev/vfio_mdev.c
diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
index 303c14ce2847..1222bc6074e1 100644
--- a/drivers/vfio/mdev/Kconfig
+++ b/drivers/vfio/mdev/Kconfig
@@ -8,3 +8,10 @@ config VFIO_MDEV
See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
If you don't know what do here, say N.
+
+config VFIO_MDEV_DEVICE
+ tristate "VFIO support for Mediated devices"
+ depends on VFIO && VFIO_MDEV
+ default n
+ help
+ VFIO based driver for mediated devices.
diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
index 31bc04801d94..fa2d5ea466ee 100644
--- a/drivers/vfio/mdev/Makefile
+++ b/drivers/vfio/mdev/Makefile
@@ -2,3 +2,4 @@
mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
obj-$(CONFIG_VFIO_MDEV) += mdev.o
+obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
new file mode 100644
index 000000000000..bb534d19e321
--- /dev/null
+++ b/drivers/vfio/mdev/vfio_mdev.c
@@ -0,0 +1,148 @@
+/*
+ * VFIO based driver for Mediated device
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vfio.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "NVIDIA Corporation"
+#define DRIVER_DESC "VFIO based driver for Mediated device"
+
+static int vfio_mdev_open(void *device_data)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+ int ret;
+
+ if (unlikely(!parent->ops->open))
+ return -EINVAL;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ ret = parent->ops->open(mdev);
+ if (ret)
+ module_put(THIS_MODULE);
+
+ return ret;
+}
+
+static void vfio_mdev_release(void *device_data)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (likely(parent->ops->release))
+ parent->ops->release(mdev);
+
+ module_put(THIS_MODULE);
+}
+
+static long vfio_mdev_unlocked_ioctl(void *device_data,
+ unsigned int cmd, unsigned long arg)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->ioctl))
+ return -EINVAL;
+
+ return parent->ops->ioctl(mdev, cmd, arg);
+}
+
+static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->read))
+ return -EINVAL;
+
+ return parent->ops->read(mdev, buf, count, ppos);
+}
+
+static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->write))
+ return -EINVAL;
+
+ return parent->ops->write(mdev, buf, count, ppos);
+}
+
+static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->mmap))
+ return -EINVAL;
+
+ return parent->ops->mmap(mdev, vma);
+}
+
+static const struct vfio_device_ops vfio_mdev_dev_ops = {
+ .name = "vfio-mdev",
+ .open = vfio_mdev_open,
+ .release = vfio_mdev_release,
+ .ioctl = vfio_mdev_unlocked_ioctl,
+ .read = vfio_mdev_read,
+ .write = vfio_mdev_write,
+ .mmap = vfio_mdev_mmap,
+};
+
+int vfio_mdev_probe(struct device *dev)
+{
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ return vfio_add_group_dev(dev, &vfio_mdev_dev_ops, mdev);
+}
+
+void vfio_mdev_remove(struct device *dev)
+{
+ vfio_del_group_dev(dev);
+}
+
+struct mdev_driver vfio_mdev_driver = {
+ .name = "vfio_mdev",
+ .probe = vfio_mdev_probe,
+ .remove = vfio_mdev_remove,
+};
+
+static int __init vfio_mdev_init(void)
+{
+ return mdev_register_driver(&vfio_mdev_driver, THIS_MODULE);
+}
+
+static void __exit vfio_mdev_exit(void)
+{
+ mdev_unregister_driver(&vfio_mdev_driver);
+}
+
+module_init(vfio_mdev_init)
+module_exit(vfio_mdev_exit)
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 02/19] vfio: VFIO based driver for Mediated devices
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: jike.song, kvm, linux-kernel, kevin.tian, qemu-devel,
Kirti Wankhede, bjsdjshi
vfio_mdev driver registers with mdev core driver.
mdev core driver creates mediated device and calls probe routine of
vfio_mdev driver for each device.
Probe routine of vfio_mdev driver adds mediated device to VFIO core module
This driver forms a shim layer that pass through VFIO devices operations
to vendor driver for mediated devices.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
---
drivers/vfio/mdev/Kconfig | 7 ++
drivers/vfio/mdev/Makefile | 1 +
drivers/vfio/mdev/vfio_mdev.c | 148 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 156 insertions(+)
create mode 100644 drivers/vfio/mdev/vfio_mdev.c
diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
index 303c14ce2847..1222bc6074e1 100644
--- a/drivers/vfio/mdev/Kconfig
+++ b/drivers/vfio/mdev/Kconfig
@@ -8,3 +8,10 @@ config VFIO_MDEV
See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
If you don't know what do here, say N.
+
+config VFIO_MDEV_DEVICE
+ tristate "VFIO support for Mediated devices"
+ depends on VFIO && VFIO_MDEV
+ default n
+ help
+ VFIO based driver for mediated devices.
diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
index 31bc04801d94..fa2d5ea466ee 100644
--- a/drivers/vfio/mdev/Makefile
+++ b/drivers/vfio/mdev/Makefile
@@ -2,3 +2,4 @@
mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
obj-$(CONFIG_VFIO_MDEV) += mdev.o
+obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
new file mode 100644
index 000000000000..bb534d19e321
--- /dev/null
+++ b/drivers/vfio/mdev/vfio_mdev.c
@@ -0,0 +1,148 @@
+/*
+ * VFIO based driver for Mediated device
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vfio.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "NVIDIA Corporation"
+#define DRIVER_DESC "VFIO based driver for Mediated device"
+
+static int vfio_mdev_open(void *device_data)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+ int ret;
+
+ if (unlikely(!parent->ops->open))
+ return -EINVAL;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ ret = parent->ops->open(mdev);
+ if (ret)
+ module_put(THIS_MODULE);
+
+ return ret;
+}
+
+static void vfio_mdev_release(void *device_data)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (likely(parent->ops->release))
+ parent->ops->release(mdev);
+
+ module_put(THIS_MODULE);
+}
+
+static long vfio_mdev_unlocked_ioctl(void *device_data,
+ unsigned int cmd, unsigned long arg)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->ioctl))
+ return -EINVAL;
+
+ return parent->ops->ioctl(mdev, cmd, arg);
+}
+
+static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->read))
+ return -EINVAL;
+
+ return parent->ops->read(mdev, buf, count, ppos);
+}
+
+static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->write))
+ return -EINVAL;
+
+ return parent->ops->write(mdev, buf, count, ppos);
+}
+
+static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->mmap))
+ return -EINVAL;
+
+ return parent->ops->mmap(mdev, vma);
+}
+
+static const struct vfio_device_ops vfio_mdev_dev_ops = {
+ .name = "vfio-mdev",
+ .open = vfio_mdev_open,
+ .release = vfio_mdev_release,
+ .ioctl = vfio_mdev_unlocked_ioctl,
+ .read = vfio_mdev_read,
+ .write = vfio_mdev_write,
+ .mmap = vfio_mdev_mmap,
+};
+
+int vfio_mdev_probe(struct device *dev)
+{
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ return vfio_add_group_dev(dev, &vfio_mdev_dev_ops, mdev);
+}
+
+void vfio_mdev_remove(struct device *dev)
+{
+ vfio_del_group_dev(dev);
+}
+
+struct mdev_driver vfio_mdev_driver = {
+ .name = "vfio_mdev",
+ .probe = vfio_mdev_probe,
+ .remove = vfio_mdev_remove,
+};
+
+static int __init vfio_mdev_init(void)
+{
+ return mdev_register_driver(&vfio_mdev_driver, THIS_MODULE);
+}
+
+static void __exit vfio_mdev_exit(void)
+{
+ mdev_unregister_driver(&vfio_mdev_driver);
+}
+
+module_init(vfio_mdev_init)
+module_exit(vfio_mdev_exit)
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 02/19] vfio: VFIO based driver for Mediated devices
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
vfio_mdev driver registers with mdev core driver.
mdev core driver creates mediated device and calls probe routine of
vfio_mdev driver for each device.
Probe routine of vfio_mdev driver adds mediated device to VFIO core module
This driver forms a shim layer that pass through VFIO devices operations
to vendor driver for mediated devices.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
---
drivers/vfio/mdev/Kconfig | 7 ++
drivers/vfio/mdev/Makefile | 1 +
drivers/vfio/mdev/vfio_mdev.c | 148 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 156 insertions(+)
create mode 100644 drivers/vfio/mdev/vfio_mdev.c
diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
index 303c14ce2847..1222bc6074e1 100644
--- a/drivers/vfio/mdev/Kconfig
+++ b/drivers/vfio/mdev/Kconfig
@@ -8,3 +8,10 @@ config VFIO_MDEV
See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
If you don't know what do here, say N.
+
+config VFIO_MDEV_DEVICE
+ tristate "VFIO support for Mediated devices"
+ depends on VFIO && VFIO_MDEV
+ default n
+ help
+ VFIO based driver for mediated devices.
diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
index 31bc04801d94..fa2d5ea466ee 100644
--- a/drivers/vfio/mdev/Makefile
+++ b/drivers/vfio/mdev/Makefile
@@ -2,3 +2,4 @@
mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
obj-$(CONFIG_VFIO_MDEV) += mdev.o
+obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
new file mode 100644
index 000000000000..bb534d19e321
--- /dev/null
+++ b/drivers/vfio/mdev/vfio_mdev.c
@@ -0,0 +1,148 @@
+/*
+ * VFIO based driver for Mediated device
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vfio.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "NVIDIA Corporation"
+#define DRIVER_DESC "VFIO based driver for Mediated device"
+
+static int vfio_mdev_open(void *device_data)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+ int ret;
+
+ if (unlikely(!parent->ops->open))
+ return -EINVAL;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ ret = parent->ops->open(mdev);
+ if (ret)
+ module_put(THIS_MODULE);
+
+ return ret;
+}
+
+static void vfio_mdev_release(void *device_data)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (likely(parent->ops->release))
+ parent->ops->release(mdev);
+
+ module_put(THIS_MODULE);
+}
+
+static long vfio_mdev_unlocked_ioctl(void *device_data,
+ unsigned int cmd, unsigned long arg)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->ioctl))
+ return -EINVAL;
+
+ return parent->ops->ioctl(mdev, cmd, arg);
+}
+
+static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->read))
+ return -EINVAL;
+
+ return parent->ops->read(mdev, buf, count, ppos);
+}
+
+static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->write))
+ return -EINVAL;
+
+ return parent->ops->write(mdev, buf, count, ppos);
+}
+
+static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
+{
+ struct mdev_device *mdev = device_data;
+ struct parent_device *parent = mdev->parent;
+
+ if (unlikely(!parent->ops->mmap))
+ return -EINVAL;
+
+ return parent->ops->mmap(mdev, vma);
+}
+
+static const struct vfio_device_ops vfio_mdev_dev_ops = {
+ .name = "vfio-mdev",
+ .open = vfio_mdev_open,
+ .release = vfio_mdev_release,
+ .ioctl = vfio_mdev_unlocked_ioctl,
+ .read = vfio_mdev_read,
+ .write = vfio_mdev_write,
+ .mmap = vfio_mdev_mmap,
+};
+
+int vfio_mdev_probe(struct device *dev)
+{
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ return vfio_add_group_dev(dev, &vfio_mdev_dev_ops, mdev);
+}
+
+void vfio_mdev_remove(struct device *dev)
+{
+ vfio_del_group_dev(dev);
+}
+
+struct mdev_driver vfio_mdev_driver = {
+ .name = "vfio_mdev",
+ .probe = vfio_mdev_probe,
+ .remove = vfio_mdev_remove,
+};
+
+static int __init vfio_mdev_init(void)
+{
+ return mdev_register_driver(&vfio_mdev_driver, THIS_MODULE);
+}
+
+static void __exit vfio_mdev_exit(void)
+{
+ mdev_unregister_driver(&vfio_mdev_driver);
+}
+
+module_init(vfio_mdev_init)
+module_exit(vfio_mdev_exit)
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 03/19] vfio: Rearrange functions to get vfio_group from dev
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
(?)
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
This patch rearranges functions to get vfio_group from device
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I1f93262bdbab75094bc24b087b29da35ba70c4c6
---
drivers/vfio/vfio.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index d1d70e0b011b..23bc86c1d05d 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -480,6 +480,21 @@ static struct vfio_group *vfio_group_get_from_minor(int minor)
return group;
}
+static struct vfio_group *vfio_group_get_from_dev(struct device *dev)
+{
+ struct iommu_group *iommu_group;
+ struct vfio_group *group;
+
+ iommu_group = iommu_group_get(dev);
+ if (!iommu_group)
+ return NULL;
+
+ group = vfio_group_get_from_iommu(iommu_group);
+ iommu_group_put(iommu_group);
+
+ return group;
+}
+
/**
* Device objects - create, release, get, put, search
*/
@@ -811,16 +826,10 @@ EXPORT_SYMBOL_GPL(vfio_add_group_dev);
*/
struct vfio_device *vfio_device_get_from_dev(struct device *dev)
{
- struct iommu_group *iommu_group;
struct vfio_group *group;
struct vfio_device *device;
- iommu_group = iommu_group_get(dev);
- if (!iommu_group)
- return NULL;
-
- group = vfio_group_get_from_iommu(iommu_group);
- iommu_group_put(iommu_group);
+ group = vfio_group_get_from_dev(dev);
if (!group)
return NULL;
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 03/19] vfio: Rearrange functions to get vfio_group from dev
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: jike.song, kvm, linux-kernel, kevin.tian, qemu-devel,
Kirti Wankhede, bjsdjshi
This patch rearranges functions to get vfio_group from device
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I1f93262bdbab75094bc24b087b29da35ba70c4c6
---
drivers/vfio/vfio.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index d1d70e0b011b..23bc86c1d05d 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -480,6 +480,21 @@ static struct vfio_group *vfio_group_get_from_minor(int minor)
return group;
}
+static struct vfio_group *vfio_group_get_from_dev(struct device *dev)
+{
+ struct iommu_group *iommu_group;
+ struct vfio_group *group;
+
+ iommu_group = iommu_group_get(dev);
+ if (!iommu_group)
+ return NULL;
+
+ group = vfio_group_get_from_iommu(iommu_group);
+ iommu_group_put(iommu_group);
+
+ return group;
+}
+
/**
* Device objects - create, release, get, put, search
*/
@@ -811,16 +826,10 @@ EXPORT_SYMBOL_GPL(vfio_add_group_dev);
*/
struct vfio_device *vfio_device_get_from_dev(struct device *dev)
{
- struct iommu_group *iommu_group;
struct vfio_group *group;
struct vfio_device *device;
- iommu_group = iommu_group_get(dev);
- if (!iommu_group)
- return NULL;
-
- group = vfio_group_get_from_iommu(iommu_group);
- iommu_group_put(iommu_group);
+ group = vfio_group_get_from_dev(dev);
if (!group)
return NULL;
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 03/19] vfio: Rearrange functions to get vfio_group from dev
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
This patch rearranges functions to get vfio_group from device
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I1f93262bdbab75094bc24b087b29da35ba70c4c6
---
drivers/vfio/vfio.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index d1d70e0b011b..23bc86c1d05d 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -480,6 +480,21 @@ static struct vfio_group *vfio_group_get_from_minor(int minor)
return group;
}
+static struct vfio_group *vfio_group_get_from_dev(struct device *dev)
+{
+ struct iommu_group *iommu_group;
+ struct vfio_group *group;
+
+ iommu_group = iommu_group_get(dev);
+ if (!iommu_group)
+ return NULL;
+
+ group = vfio_group_get_from_iommu(iommu_group);
+ iommu_group_put(iommu_group);
+
+ return group;
+}
+
/**
* Device objects - create, release, get, put, search
*/
@@ -811,16 +826,10 @@ EXPORT_SYMBOL_GPL(vfio_add_group_dev);
*/
struct vfio_device *vfio_device_get_from_dev(struct device *dev)
{
- struct iommu_group *iommu_group;
struct vfio_group *group;
struct vfio_device *device;
- iommu_group = iommu_group_get(dev);
- if (!iommu_group)
- return NULL;
-
- group = vfio_group_get_from_iommu(iommu_group);
- iommu_group_put(iommu_group);
+ group = vfio_group_get_from_dev(dev);
if (!group)
return NULL;
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 04/19] vfio: Common function to increment container_users
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
This change rearrange functions to have common function to increment
container_users
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I8bdeb352bc8439b107ffd519480fd4dc238677f2
---
drivers/vfio/vfio.c | 34 +++++++++++++++++++++-------------
1 file changed, 21 insertions(+), 13 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 23bc86c1d05d..2e83bdf007fe 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1385,6 +1385,23 @@ static bool vfio_group_viable(struct vfio_group *group)
group, vfio_dev_viable) == 0);
}
+static int vfio_group_add_container_user(struct vfio_group *group)
+{
+ if (!atomic_inc_not_zero(&group->container_users))
+ return -EINVAL;
+
+ if (group->noiommu) {
+ atomic_dec(&group->container_users);
+ return -EPERM;
+ }
+ if (!group->container->iommu_driver || !vfio_group_viable(group)) {
+ atomic_dec(&group->container_users);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static const struct file_operations vfio_device_fops;
static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
@@ -1694,23 +1711,14 @@ static const struct file_operations vfio_device_fops = {
struct vfio_group *vfio_group_get_external_user(struct file *filep)
{
struct vfio_group *group = filep->private_data;
+ int ret;
if (filep->f_op != &vfio_group_fops)
return ERR_PTR(-EINVAL);
- if (!atomic_inc_not_zero(&group->container_users))
- return ERR_PTR(-EINVAL);
-
- if (group->noiommu) {
- atomic_dec(&group->container_users);
- return ERR_PTR(-EPERM);
- }
-
- if (!group->container->iommu_driver ||
- !vfio_group_viable(group)) {
- atomic_dec(&group->container_users);
- return ERR_PTR(-EINVAL);
- }
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ return ERR_PTR(ret);
vfio_group_get(group);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 04/19] vfio: Common function to increment container_users
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
This change rearrange functions to have common function to increment
container_users
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I8bdeb352bc8439b107ffd519480fd4dc238677f2
---
drivers/vfio/vfio.c | 34 +++++++++++++++++++++-------------
1 file changed, 21 insertions(+), 13 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 23bc86c1d05d..2e83bdf007fe 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1385,6 +1385,23 @@ static bool vfio_group_viable(struct vfio_group *group)
group, vfio_dev_viable) == 0);
}
+static int vfio_group_add_container_user(struct vfio_group *group)
+{
+ if (!atomic_inc_not_zero(&group->container_users))
+ return -EINVAL;
+
+ if (group->noiommu) {
+ atomic_dec(&group->container_users);
+ return -EPERM;
+ }
+ if (!group->container->iommu_driver || !vfio_group_viable(group)) {
+ atomic_dec(&group->container_users);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static const struct file_operations vfio_device_fops;
static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
@@ -1694,23 +1711,14 @@ static const struct file_operations vfio_device_fops = {
struct vfio_group *vfio_group_get_external_user(struct file *filep)
{
struct vfio_group *group = filep->private_data;
+ int ret;
if (filep->f_op != &vfio_group_fops)
return ERR_PTR(-EINVAL);
- if (!atomic_inc_not_zero(&group->container_users))
- return ERR_PTR(-EINVAL);
-
- if (group->noiommu) {
- atomic_dec(&group->container_users);
- return ERR_PTR(-EPERM);
- }
-
- if (!group->container->iommu_driver ||
- !vfio_group_viable(group)) {
- atomic_dec(&group->container_users);
- return ERR_PTR(-EINVAL);
- }
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ return ERR_PTR(ret);
vfio_group_get(group);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 05/19] vfio iommu: Added pin and unpin callback functions to vfio_iommu_driver_ops
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Added two new callback functions to struct vfio_iommu_driver_ops. Backend
IOMMU module that supports pining and unpinning pages for mdev devices
should provide these functions.
Added APIs for pining and unpining pages to VFIO module. These calls back
into backend iommu module to actually pin and unpin pages.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Ia7417723aaae86bec2959ad9ae6c2915ddd340e0
---
drivers/vfio/vfio.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/vfio.h | 12 ++++++-
2 files changed, 103 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 2e83bdf007fe..28b50ca14c52 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1799,6 +1799,98 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
}
EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
+
+/*
+ * Pin a set of guest PFNs and return their associated host PFNs for local
+ * domain only.
+ * @dev [in] : device
+ * @user_pfn [in]: array of user/guest PFNs
+ * @npage [in]: count of array elements
+ * @prot [in] : protection flags
+ * @phys_pfn[out] : array of host PFNs
+ */
+long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+ long npage, int prot, unsigned long *phys_pfn)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !user_pfn || !phys_pfn)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_pin_pages;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->pin_pages))
+ ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
+ npage, prot, phys_pfn);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_pin_pages:
+ vfio_group_put(group);
+ return ret;
+
+}
+EXPORT_SYMBOL(vfio_pin_pages);
+
+/*
+ * Unpin set of host PFNs for local domain only.
+ * @dev [in] : device
+ * @pfn [in] : array of host PFNs to be unpinned.
+ * @npage [in] :count of elements in array, that is number of pages.
+ */
+long vfio_unpin_pages(struct device *dev, unsigned long *pfn, long npage)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !pfn)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_unpin_pages;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->unpin_pages))
+ ret = driver->ops->unpin_pages(container->iommu_data, pfn,
+ npage);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_unpin_pages:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_unpin_pages);
+
/**
* Module/class support
*/
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 0ecae0b1cd34..0609a2052846 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -75,7 +75,11 @@ struct vfio_iommu_driver_ops {
struct iommu_group *group);
void (*detach_group)(void *iommu_data,
struct iommu_group *group);
-
+ long (*pin_pages)(void *iommu_data, unsigned long *user_pfn,
+ long npage, int prot,
+ unsigned long *phys_pfn);
+ long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
+ long npage);
};
extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
@@ -127,6 +131,12 @@ static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
}
#endif /* CONFIG_EEH */
+extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+ long npage, int prot, unsigned long *phys_pfn);
+
+extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
+ long npage);
+
/*
* IRQfd - generic
*/
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 05/19] vfio iommu: Added pin and unpin callback functions to vfio_iommu_driver_ops
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Added two new callback functions to struct vfio_iommu_driver_ops. Backend
IOMMU module that supports pining and unpinning pages for mdev devices
should provide these functions.
Added APIs for pining and unpining pages to VFIO module. These calls back
into backend iommu module to actually pin and unpin pages.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Ia7417723aaae86bec2959ad9ae6c2915ddd340e0
---
drivers/vfio/vfio.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/vfio.h | 12 ++++++-
2 files changed, 103 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 2e83bdf007fe..28b50ca14c52 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1799,6 +1799,98 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
}
EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
+
+/*
+ * Pin a set of guest PFNs and return their associated host PFNs for local
+ * domain only.
+ * @dev [in] : device
+ * @user_pfn [in]: array of user/guest PFNs
+ * @npage [in]: count of array elements
+ * @prot [in] : protection flags
+ * @phys_pfn[out] : array of host PFNs
+ */
+long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+ long npage, int prot, unsigned long *phys_pfn)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !user_pfn || !phys_pfn)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_pin_pages;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->pin_pages))
+ ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
+ npage, prot, phys_pfn);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_pin_pages:
+ vfio_group_put(group);
+ return ret;
+
+}
+EXPORT_SYMBOL(vfio_pin_pages);
+
+/*
+ * Unpin set of host PFNs for local domain only.
+ * @dev [in] : device
+ * @pfn [in] : array of host PFNs to be unpinned.
+ * @npage [in] :count of elements in array, that is number of pages.
+ */
+long vfio_unpin_pages(struct device *dev, unsigned long *pfn, long npage)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !pfn)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_unpin_pages;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->unpin_pages))
+ ret = driver->ops->unpin_pages(container->iommu_data, pfn,
+ npage);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_unpin_pages:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_unpin_pages);
+
/**
* Module/class support
*/
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 0ecae0b1cd34..0609a2052846 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -75,7 +75,11 @@ struct vfio_iommu_driver_ops {
struct iommu_group *group);
void (*detach_group)(void *iommu_data,
struct iommu_group *group);
-
+ long (*pin_pages)(void *iommu_data, unsigned long *user_pfn,
+ long npage, int prot,
+ unsigned long *phys_pfn);
+ long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
+ long npage);
};
extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
@@ -127,6 +131,12 @@ static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
}
#endif /* CONFIG_EEH */
+extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+ long npage, int prot, unsigned long *phys_pfn);
+
+extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
+ long npage);
+
/*
* IRQfd - generic
*/
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 06/19] vfio iommu type1: Update arguments of vfio_lock_acct
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Updated arguments of vfio_lock_acct to take task as input argument
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I5d3673cc9d3786bb436b395d5f74537f1a36da80
---
drivers/vfio/vfio_iommu_type1.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 2ba19424e4a1..72fee415044a 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -150,17 +150,17 @@ static void vfio_lock_acct_bg(struct work_struct *work)
kfree(vwork);
}
-static void vfio_lock_acct(long npage)
+static void vfio_lock_acct(struct task_struct *task, long npage)
{
struct vwork *vwork;
struct mm_struct *mm;
- if (!current->mm || !npage)
+ if (!task->mm || !npage)
return; /* process exited or nothing to do */
- if (down_write_trylock(¤t->mm->mmap_sem)) {
- current->mm->locked_vm += npage;
- up_write(¤t->mm->mmap_sem);
+ if (down_write_trylock(&task->mm->mmap_sem)) {
+ task->mm->locked_vm += npage;
+ up_write(&task->mm->mmap_sem);
return;
}
@@ -172,7 +172,7 @@ static void vfio_lock_acct(long npage)
vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL);
if (!vwork)
return;
- mm = get_task_mm(current);
+ mm = get_task_mm(task);
if (!mm) {
kfree(vwork);
return;
@@ -285,7 +285,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
if (unlikely(disable_hugepages)) {
if (!rsvd)
- vfio_lock_acct(1);
+ vfio_lock_acct(current, 1);
return 1;
}
@@ -313,7 +313,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
}
if (!rsvd)
- vfio_lock_acct(i);
+ vfio_lock_acct(current, i);
return i;
}
@@ -328,7 +328,7 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
unlocked += put_pfn(pfn++, prot);
if (do_accounting)
- vfio_lock_acct(-unlocked);
+ vfio_lock_acct(current, -unlocked);
return unlocked;
}
@@ -390,7 +390,7 @@ static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
cond_resched();
}
- vfio_lock_acct(-unlocked);
+ vfio_lock_acct(current, -unlocked);
}
static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 06/19] vfio iommu type1: Update arguments of vfio_lock_acct
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Updated arguments of vfio_lock_acct to take task as input argument
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I5d3673cc9d3786bb436b395d5f74537f1a36da80
---
drivers/vfio/vfio_iommu_type1.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 2ba19424e4a1..72fee415044a 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -150,17 +150,17 @@ static void vfio_lock_acct_bg(struct work_struct *work)
kfree(vwork);
}
-static void vfio_lock_acct(long npage)
+static void vfio_lock_acct(struct task_struct *task, long npage)
{
struct vwork *vwork;
struct mm_struct *mm;
- if (!current->mm || !npage)
+ if (!task->mm || !npage)
return; /* process exited or nothing to do */
- if (down_write_trylock(¤t->mm->mmap_sem)) {
- current->mm->locked_vm += npage;
- up_write(¤t->mm->mmap_sem);
+ if (down_write_trylock(&task->mm->mmap_sem)) {
+ task->mm->locked_vm += npage;
+ up_write(&task->mm->mmap_sem);
return;
}
@@ -172,7 +172,7 @@ static void vfio_lock_acct(long npage)
vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL);
if (!vwork)
return;
- mm = get_task_mm(current);
+ mm = get_task_mm(task);
if (!mm) {
kfree(vwork);
return;
@@ -285,7 +285,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
if (unlikely(disable_hugepages)) {
if (!rsvd)
- vfio_lock_acct(1);
+ vfio_lock_acct(current, 1);
return 1;
}
@@ -313,7 +313,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
}
if (!rsvd)
- vfio_lock_acct(i);
+ vfio_lock_acct(current, i);
return i;
}
@@ -328,7 +328,7 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
unlocked += put_pfn(pfn++, prot);
if (do_accounting)
- vfio_lock_acct(-unlocked);
+ vfio_lock_acct(current, -unlocked);
return unlocked;
}
@@ -390,7 +390,7 @@ static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
cond_resched();
}
- vfio_lock_acct(-unlocked);
+ vfio_lock_acct(current, -unlocked);
}
static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
argument.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
---
drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 72fee415044a..3d916b965492 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
return 0;
}
-static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
+static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
+ int prot, unsigned long *pfn)
{
struct page *page[1];
struct vm_area_struct *vma;
+ struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
int ret = -EFAULT;
- if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
+ if (remote_mm) {
+ down_read(&mm->mmap_sem);
+ ret = get_user_pages_remote(NULL, mm, vaddr, 1,
+ !!(prot & IOMMU_WRITE), 0, page, NULL);
+ up_read(&mm->mmap_sem);
+ } else
+ ret = get_user_pages_fast(vaddr, 1,
+ !!(prot & IOMMU_WRITE), page);
+
+ if (ret == 1) {
*pfn = page_to_pfn(page[0]);
return 0;
}
- down_read(¤t->mm->mmap_sem);
+ down_read(&mm->mmap_sem);
- vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
+ vma = find_vma_intersection(mm, vaddr, vaddr + 1);
if (vma && vma->vm_flags & VM_PFNMAP) {
*pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
@@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
ret = 0;
}
- up_read(¤t->mm->mmap_sem);
+ up_read(&mm->mmap_sem);
return ret;
}
@@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
if (!current->mm)
return -ENODEV;
- ret = vaddr_get_pfn(vaddr, prot, pfn_base);
+ ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
if (ret)
return ret;
@@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
unsigned long pfn = 0;
- ret = vaddr_get_pfn(vaddr, prot, &pfn);
+ ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
if (ret)
break;
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
argument.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
---
drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 72fee415044a..3d916b965492 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
return 0;
}
-static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
+static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
+ int prot, unsigned long *pfn)
{
struct page *page[1];
struct vm_area_struct *vma;
+ struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
int ret = -EFAULT;
- if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
+ if (remote_mm) {
+ down_read(&mm->mmap_sem);
+ ret = get_user_pages_remote(NULL, mm, vaddr, 1,
+ !!(prot & IOMMU_WRITE), 0, page, NULL);
+ up_read(&mm->mmap_sem);
+ } else
+ ret = get_user_pages_fast(vaddr, 1,
+ !!(prot & IOMMU_WRITE), page);
+
+ if (ret == 1) {
*pfn = page_to_pfn(page[0]);
return 0;
}
- down_read(¤t->mm->mmap_sem);
+ down_read(&mm->mmap_sem);
- vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
+ vma = find_vma_intersection(mm, vaddr, vaddr + 1);
if (vma && vma->vm_flags & VM_PFNMAP) {
*pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
@@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
ret = 0;
}
- up_read(¤t->mm->mmap_sem);
+ up_read(&mm->mmap_sem);
return ret;
}
@@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
if (!current->mm)
return -ENODEV;
- ret = vaddr_get_pfn(vaddr, prot, pfn_base);
+ ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
if (ret)
return ret;
@@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
unsigned long pfn = 0;
- ret = vaddr_get_pfn(vaddr, prot, &pfn);
+ ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
if (ret)
break;
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 08/19] vfio iommu type1: Add find_iommu_group() function
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Add find_iommu_group()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I9d372f1ebe9eb01a5a21374b8a2b03f7df73601f
---
drivers/vfio/vfio_iommu_type1.c | 58 ++++++++++++++++++++++++-----------------
1 file changed, 34 insertions(+), 24 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 3d916b965492..861ac2a1b0c3 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -745,11 +745,24 @@ static void vfio_test_domain_fgsp(struct vfio_domain *domain)
__free_pages(pages, order);
}
+static struct vfio_group *find_iommu_group(struct vfio_domain *domain,
+ struct iommu_group *iommu_group)
+{
+ struct vfio_group *g;
+
+ list_for_each_entry(g, &domain->group_list, next) {
+ if (g->iommu_group == iommu_group)
+ return g;
+ }
+
+ return NULL;
+}
+
static int vfio_iommu_type1_attach_group(void *iommu_data,
struct iommu_group *iommu_group)
{
struct vfio_iommu *iommu = iommu_data;
- struct vfio_group *group, *g;
+ struct vfio_group *group;
struct vfio_domain *domain, *d;
struct bus_type *bus = NULL;
int ret;
@@ -757,10 +770,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
mutex_lock(&iommu->lock);
list_for_each_entry(d, &iommu->domain_list, next) {
- list_for_each_entry(g, &d->group_list, next) {
- if (g->iommu_group != iommu_group)
- continue;
-
+ if (find_iommu_group(d, iommu_group)) {
mutex_unlock(&iommu->lock);
return -EINVAL;
}
@@ -879,28 +889,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
mutex_lock(&iommu->lock);
+
list_for_each_entry(domain, &iommu->domain_list, next) {
- list_for_each_entry(group, &domain->group_list, next) {
- if (group->iommu_group != iommu_group)
- continue;
+ group = find_iommu_group(domain, iommu_group);
+ if (!group)
+ continue;
- iommu_detach_group(domain->domain, iommu_group);
- list_del(&group->next);
- kfree(group);
- /*
- * Group ownership provides privilege, if the group
- * list is empty, the domain goes away. If it's the
- * last domain, then all the mappings go away too.
- */
- if (list_empty(&domain->group_list)) {
- if (list_is_singular(&iommu->domain_list))
- vfio_iommu_unmap_unpin_all(iommu);
- iommu_domain_free(domain->domain);
- list_del(&domain->next);
- kfree(domain);
- }
- goto done;
+ iommu_detach_group(domain->domain, iommu_group);
+ list_del(&group->next);
+ kfree(group);
+ /*
+ * Group ownership provides privilege, if the group
+ * list is empty, the domain goes away. If it's the
+ * last domain, then all the mappings go away too.
+ */
+ if (list_empty(&domain->group_list)) {
+ if (list_is_singular(&iommu->domain_list))
+ vfio_iommu_unmap_unpin_all(iommu);
+ iommu_domain_free(domain->domain);
+ list_del(&domain->next);
+ kfree(domain);
}
+ goto done;
}
done:
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 08/19] vfio iommu type1: Add find_iommu_group() function
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Add find_iommu_group()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I9d372f1ebe9eb01a5a21374b8a2b03f7df73601f
---
drivers/vfio/vfio_iommu_type1.c | 58 ++++++++++++++++++++++++-----------------
1 file changed, 34 insertions(+), 24 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 3d916b965492..861ac2a1b0c3 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -745,11 +745,24 @@ static void vfio_test_domain_fgsp(struct vfio_domain *domain)
__free_pages(pages, order);
}
+static struct vfio_group *find_iommu_group(struct vfio_domain *domain,
+ struct iommu_group *iommu_group)
+{
+ struct vfio_group *g;
+
+ list_for_each_entry(g, &domain->group_list, next) {
+ if (g->iommu_group == iommu_group)
+ return g;
+ }
+
+ return NULL;
+}
+
static int vfio_iommu_type1_attach_group(void *iommu_data,
struct iommu_group *iommu_group)
{
struct vfio_iommu *iommu = iommu_data;
- struct vfio_group *group, *g;
+ struct vfio_group *group;
struct vfio_domain *domain, *d;
struct bus_type *bus = NULL;
int ret;
@@ -757,10 +770,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
mutex_lock(&iommu->lock);
list_for_each_entry(d, &iommu->domain_list, next) {
- list_for_each_entry(g, &d->group_list, next) {
- if (g->iommu_group != iommu_group)
- continue;
-
+ if (find_iommu_group(d, iommu_group)) {
mutex_unlock(&iommu->lock);
return -EINVAL;
}
@@ -879,28 +889,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
mutex_lock(&iommu->lock);
+
list_for_each_entry(domain, &iommu->domain_list, next) {
- list_for_each_entry(group, &domain->group_list, next) {
- if (group->iommu_group != iommu_group)
- continue;
+ group = find_iommu_group(domain, iommu_group);
+ if (!group)
+ continue;
- iommu_detach_group(domain->domain, iommu_group);
- list_del(&group->next);
- kfree(group);
- /*
- * Group ownership provides privilege, if the group
- * list is empty, the domain goes away. If it's the
- * last domain, then all the mappings go away too.
- */
- if (list_empty(&domain->group_list)) {
- if (list_is_singular(&iommu->domain_list))
- vfio_iommu_unmap_unpin_all(iommu);
- iommu_domain_free(domain->domain);
- list_del(&domain->next);
- kfree(domain);
- }
- goto done;
+ iommu_detach_group(domain->domain, iommu_group);
+ list_del(&group->next);
+ kfree(group);
+ /*
+ * Group ownership provides privilege, if the group
+ * list is empty, the domain goes away. If it's the
+ * last domain, then all the mappings go away too.
+ */
+ if (list_empty(&domain->group_list)) {
+ if (list_is_singular(&iommu->domain_list))
+ vfio_iommu_unmap_unpin_all(iommu);
+ iommu_domain_free(domain->domain);
+ list_del(&domain->next);
+ kfree(domain);
}
+ goto done;
}
done:
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 09/19] vfio iommu type1: Add support for mediated devices
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
VFIO IOMMU drivers are designed for the devices which are IOMMU capable.
Mediated device only uses IOMMU APIs, the underlying hardware can be
managed by an IOMMU domain.
Aim of this change is:
- To use most of the code of TYPE1 IOMMU driver for mediated devices
- To support direct assigned device and mediated device in single module
This change adds pin and unpin support for mediated device to TYPE1 IOMMU
backend module. More details:
- When iommu_group of mediated devices is attached, task structure is
cached which is used later to pin pages and page accounting.
- It keeps track of pinned pages for mediated domain. This data is used to
verify unpinning request and to unpin remaining pages while detaching, if
there are any.
- Used existing mechanism for page accounting. If iommu capable domain
exist in the container then all pages are already pinned and accounted.
Accouting for mdev device is only done if there is no iommu capable
domain in the container.
- Page accouting is updated on hot plug and unplug mdev device and pass
through device.
Tested by assigning below combinations of devices to a single VM:
- GPU pass through only
- vGPU device only
- One GPU pass through and one vGPU device
- Linux VM hot plug and unplug vGPU device while GPU pass through device
exist
- Linux VM hot plug and unplug GPU pass through device while vGPU device
exist
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I295d6f0f2e0579b8d9882bfd8fd5a4194b97bd9a
---
drivers/vfio/vfio_iommu_type1.c | 646 +++++++++++++++++++++++++++++++++++-----
1 file changed, 571 insertions(+), 75 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 861ac2a1b0c3..5add11a147e1 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -36,6 +36,7 @@
#include <linux/uaccess.h>
#include <linux/vfio.h>
#include <linux/workqueue.h>
+#include <linux/mdev.h>
#define DRIVER_VERSION "0.2"
#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
@@ -55,18 +56,26 @@ MODULE_PARM_DESC(disable_hugepages,
struct vfio_iommu {
struct list_head domain_list;
+ struct vfio_domain *external_domain; /* domain for external user */
struct mutex lock;
struct rb_root dma_list;
bool v2;
bool nesting;
};
+struct external_addr_space {
+ struct task_struct *task;
+ struct rb_root pfn_list; /* pinned Host pfn list */
+ struct mutex pfn_list_lock; /* mutex for pfn_list */
+};
+
struct vfio_domain {
- struct iommu_domain *domain;
- struct list_head next;
- struct list_head group_list;
- int prot; /* IOMMU_CACHE */
- bool fgsp; /* Fine-grained super pages */
+ struct iommu_domain *domain;
+ struct list_head next;
+ struct list_head group_list;
+ struct external_addr_space *external_addr_space;
+ int prot; /* IOMMU_CACHE */
+ bool fgsp; /* Fine-grained super pages */
};
struct vfio_dma {
@@ -75,6 +84,7 @@ struct vfio_dma {
unsigned long vaddr; /* Process virtual addr */
size_t size; /* Map size (bytes) */
int prot; /* IOMMU_READ/WRITE */
+ bool iommu_mapped;
};
struct vfio_group {
@@ -83,6 +93,21 @@ struct vfio_group {
};
/*
+ * Guest RAM pinning working set or DMA target
+ */
+struct vfio_pfn {
+ struct rb_node node;
+ unsigned long vaddr; /* virtual addr */
+ dma_addr_t iova; /* IOVA */
+ unsigned long pfn; /* Host pfn */
+ int prot;
+ atomic_t ref_count;
+};
+
+#define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \
+ (!list_empty(&iommu->domain_list))
+
+/*
* This code handles mapping and unmapping of user data buffers
* into DMA'ble space using the IOMMU
*/
@@ -130,6 +155,101 @@ static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
rb_erase(&old->node, &iommu->dma_list);
}
+/*
+ * Helper Functions for host pfn list
+ */
+
+static struct vfio_pfn *vfio_find_pfn(struct vfio_domain *domain,
+ unsigned long pfn)
+{
+ struct rb_node *node;
+ struct vfio_pfn *vpfn;
+
+ node = domain->external_addr_space->pfn_list.rb_node;
+
+ while (node) {
+ vpfn = rb_entry(node, struct vfio_pfn, node);
+
+ if (pfn < vpfn->pfn)
+ node = node->rb_left;
+ else if (pfn > vpfn->pfn)
+ node = node->rb_right;
+ else
+ return vpfn;
+ }
+
+ return NULL;
+}
+
+static void vfio_link_pfn(struct vfio_domain *domain, struct vfio_pfn *new)
+{
+ struct rb_node **link, *parent = NULL;
+ struct vfio_pfn *vpfn;
+
+ link = &domain->external_addr_space->pfn_list.rb_node;
+ while (*link) {
+ parent = *link;
+ vpfn = rb_entry(parent, struct vfio_pfn, node);
+
+ if (new->pfn < vpfn->pfn)
+ link = &(*link)->rb_left;
+ else
+ link = &(*link)->rb_right;
+ }
+
+ rb_link_node(&new->node, parent, link);
+ rb_insert_color(&new->node, &domain->external_addr_space->pfn_list);
+}
+
+static void vfio_unlink_pfn(struct vfio_domain *domain, struct vfio_pfn *old)
+{
+ rb_erase(&old->node, &domain->external_addr_space->pfn_list);
+}
+
+static int vfio_add_to_pfn_list(struct vfio_domain *domain, unsigned long vaddr,
+ dma_addr_t iova, unsigned long pfn, int prot)
+{
+ struct vfio_pfn *vpfn;
+
+ vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
+ if (!vpfn)
+ return -ENOMEM;
+
+ vpfn->vaddr = vaddr;
+ vpfn->iova = iova;
+ vpfn->pfn = pfn;
+ vpfn->prot = prot;
+ atomic_set(&vpfn->ref_count, 1);
+ vfio_link_pfn(domain, vpfn);
+ return 0;
+}
+
+static void vfio_remove_from_pfn_list(struct vfio_domain *domain,
+ struct vfio_pfn *vpfn)
+{
+ vfio_unlink_pfn(domain, vpfn);
+ kfree(vpfn);
+}
+
+static int vfio_pfn_account(struct vfio_iommu *iommu, unsigned long pfn)
+{
+ struct vfio_pfn *p;
+ struct vfio_domain *domain = iommu->external_domain;
+ int ret = 1;
+
+ if (!domain)
+ return 1;
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ p = vfio_find_pfn(domain, pfn);
+ if (p)
+ ret = 0;
+
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+ return ret;
+}
+
struct vwork {
struct mm_struct *mm;
long npage;
@@ -270,12 +390,13 @@ static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
* the iommu can only map chunks of consecutive pfns anyway, so get the
* first page and all consecutive pages with the same locking.
*/
-static long vfio_pin_pages(unsigned long vaddr, long npage,
- int prot, unsigned long *pfn_base)
+static long __vfio_pin_pages_remote(struct vfio_iommu *iommu,
+ unsigned long vaddr, long npage,
+ int prot, unsigned long *pfn_base)
{
unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
bool lock_cap = capable(CAP_IPC_LOCK);
- long ret, i;
+ long ret, i, lock_acct = 0;
bool rsvd;
if (!current->mm)
@@ -285,9 +406,11 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
if (ret)
return ret;
+ lock_acct = vfio_pfn_account(iommu, *pfn_base);
+
rsvd = is_invalid_reserved_pfn(*pfn_base);
- if (!rsvd && !lock_cap && current->mm->locked_vm + 1 > limit) {
+ if (!rsvd && !lock_cap && current->mm->locked_vm + lock_acct > limit) {
put_pfn(*pfn_base, prot);
pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
limit << PAGE_SHIFT);
@@ -314,8 +437,10 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
break;
}
+ lock_acct += vfio_pfn_account(iommu, pfn);
+
if (!rsvd && !lock_cap &&
- current->mm->locked_vm + i + 1 > limit) {
+ current->mm->locked_vm + lock_acct > limit) {
put_pfn(pfn, prot);
pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
__func__, limit << PAGE_SHIFT);
@@ -329,14 +454,19 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
return i;
}
-static long vfio_unpin_pages(unsigned long pfn, long npage,
- int prot, bool do_accounting)
+static long __vfio_unpin_pages_remote(struct vfio_iommu *iommu,
+ unsigned long pfn, long npage, int prot,
+ bool do_accounting)
{
- unsigned long unlocked = 0;
+ unsigned long unlocked = 0, unlock_acct = 0;
long i;
- for (i = 0; i < npage; i++)
+ for (i = 0; i < npage; i++) {
+ if (do_accounting)
+ unlock_acct += vfio_pfn_account(iommu, pfn);
+
unlocked += put_pfn(pfn++, prot);
+ }
if (do_accounting)
vfio_lock_acct(current, -unlocked);
@@ -344,14 +474,208 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
return unlocked;
}
-static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
+static long __vfio_pin_page_external(struct vfio_domain *domain,
+ unsigned long vaddr, int prot,
+ unsigned long *pfn_base,
+ bool do_accounting)
+{
+ unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ bool lock_cap = capable(CAP_IPC_LOCK);
+ long ret;
+ bool rsvd;
+ struct task_struct *task = domain->external_addr_space->task;
+
+ if (!task->mm)
+ return -ENODEV;
+
+ ret = vaddr_get_pfn(task->mm, vaddr, prot, pfn_base);
+ if (ret)
+ return ret;
+
+ rsvd = is_invalid_reserved_pfn(*pfn_base);
+
+ if (!rsvd && !lock_cap && task->mm->locked_vm + 1 > limit) {
+ put_pfn(*pfn_base, prot);
+ pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
+ limit << PAGE_SHIFT);
+ return -ENOMEM;
+ }
+
+ if (!rsvd && do_accounting)
+ vfio_lock_acct(task, 1);
+
+ return 1;
+}
+
+static void __vfio_unpin_page_external(struct vfio_domain *domain,
+ unsigned long pfn, int prot,
+ bool do_accounting)
+{
+ put_pfn(pfn, prot);
+
+ if (do_accounting)
+ vfio_lock_acct(domain->external_addr_space->task, -1);
+}
+
+static int vfio_unpin_pfn(struct vfio_domain *domain,
+ struct vfio_pfn *vpfn, bool do_accounting)
+{
+ __vfio_unpin_page_external(domain, vpfn->pfn, vpfn->prot,
+ do_accounting);
+
+ if (atomic_dec_and_test(&vpfn->ref_count))
+ vfio_remove_from_pfn_list(domain, vpfn);
+
+ return 1;
+}
+
+static long vfio_iommu_type1_pin_pages(void *iommu_data,
+ unsigned long *user_pfn,
+ long npage, int prot,
+ unsigned long *phys_pfn)
+{
+ struct vfio_iommu *iommu = iommu_data;
+ struct vfio_domain *domain;
+ struct external_addr_space *addr_space;
+ int i, j, ret;
+ long retpage;
+ unsigned long remote_vaddr;
+ unsigned long *pfn = phys_pfn;
+ struct vfio_dma *dma;
+ bool do_accounting;
+
+ if (!iommu || !user_pfn || !phys_pfn)
+ return -EINVAL;
+
+ mutex_lock(&iommu->lock);
+
+ if (!iommu->external_domain) {
+ ret = -EINVAL;
+ goto pin_done;
+ }
+
+ domain = iommu->external_domain;
+ addr_space = domain->external_addr_space;
+ /*
+ * If iommu capable domain exist in the container then all pages are
+ * already pinned and accounted. Accouting should be done if there is no
+ * iommu capable domain in the container.
+ */
+ do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
+
+ for (i = 0; i < npage; i++) {
+ struct vfio_pfn *p;
+ dma_addr_t iova;
+
+ iova = user_pfn[i] << PAGE_SHIFT;
+
+ dma = vfio_find_dma(iommu, iova, 0);
+ if (!dma) {
+ ret = -EINVAL;
+ goto pin_unwind;
+ }
+
+ remote_vaddr = dma->vaddr + iova - dma->iova;
+
+ retpage = __vfio_pin_page_external(domain, remote_vaddr, prot,
+ &pfn[i], do_accounting);
+ if (retpage <= 0) {
+ WARN_ON(!retpage);
+ ret = (int)retpage;
+ goto pin_unwind;
+ }
+
+ mutex_lock(&addr_space->pfn_list_lock);
+
+ /* search if pfn exist */
+ p = vfio_find_pfn(domain, pfn[i]);
+ if (p) {
+ atomic_inc(&p->ref_count);
+ mutex_unlock(&addr_space->pfn_list_lock);
+ continue;
+ }
+
+ ret = vfio_add_to_pfn_list(domain, remote_vaddr, iova,
+ pfn[i], prot);
+ mutex_unlock(&addr_space->pfn_list_lock);
+
+ if (ret) {
+ __vfio_unpin_page_external(domain, pfn[i], prot,
+ do_accounting);
+ goto pin_unwind;
+ }
+ }
+
+ ret = i;
+ goto pin_done;
+
+pin_unwind:
+ pfn[i] = 0;
+ mutex_lock(&addr_space->pfn_list_lock);
+ for (j = 0; j < i; j++) {
+ struct vfio_pfn *p;
+
+ p = vfio_find_pfn(domain, pfn[j]);
+ if (p)
+ vfio_unpin_pfn(domain, p, do_accounting);
+
+ pfn[j] = 0;
+ }
+ mutex_unlock(&addr_space->pfn_list_lock);
+
+pin_done:
+ mutex_unlock(&iommu->lock);
+ return ret;
+}
+
+static long vfio_iommu_type1_unpin_pages(void *iommu_data, unsigned long *pfn,
+ long npage)
+{
+ struct vfio_iommu *iommu = iommu_data;
+ struct vfio_domain *domain = NULL;
+ bool do_accounting;
+ long unlocked = 0;
+ int i;
+
+ if (!iommu || !pfn)
+ return -EINVAL;
+
+ mutex_lock(&iommu->lock);
+
+ domain = iommu->external_domain;
+
+ do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ for (i = 0; i < npage; i++) {
+ struct vfio_pfn *p;
+
+ /* verify if pfn exist in pfn_list */
+ p = vfio_find_pfn(domain, pfn[i]);
+ if (p)
+ unlocked += vfio_unpin_pfn(domain, p, do_accounting);
+
+ }
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+
+ mutex_unlock(&iommu->lock);
+ return unlocked;
+}
+
+static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
+ bool do_accounting)
{
dma_addr_t iova = dma->iova, end = dma->iova + dma->size;
struct vfio_domain *domain, *d;
long unlocked = 0;
if (!dma->size)
- return;
+ return 0;
+
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
+ return 0;
+
/*
* We use the IOMMU to track the physical addresses, otherwise we'd
* need a much more complicated tracking system. Unfortunately that
@@ -393,20 +717,27 @@ static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
if (WARN_ON(!unmapped))
break;
- unlocked += vfio_unpin_pages(phys >> PAGE_SHIFT,
- unmapped >> PAGE_SHIFT,
- dma->prot, false);
+ unlocked += __vfio_unpin_pages_remote(iommu, phys >> PAGE_SHIFT,
+ unmapped >> PAGE_SHIFT,
+ dma->prot, false);
iova += unmapped;
cond_resched();
}
- vfio_lock_acct(current, -unlocked);
+ dma->iommu_mapped = false;
+
+ if (do_accounting) {
+ vfio_lock_acct(current, -unlocked);
+ return 0;
+ }
+
+ return unlocked;
}
static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
{
- vfio_unmap_unpin(iommu, dma);
+ vfio_unmap_unpin(iommu, dma, true);
vfio_unlink_dma(iommu, dma);
kfree(dma);
}
@@ -569,17 +900,57 @@ unwind:
return ret;
}
+static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma,
+ size_t map_size)
+{
+ dma_addr_t iova = dma->iova;
+ unsigned long vaddr = dma->vaddr;
+ size_t size = map_size;
+ long npage;
+ unsigned long pfn;
+ int ret = 0;
+
+ while (size) {
+ /* Pin a contiguous chunk of memory */
+ npage = __vfio_pin_pages_remote(iommu, vaddr + dma->size,
+ size >> PAGE_SHIFT, dma->prot,
+ &pfn);
+ if (npage <= 0) {
+ WARN_ON(!npage);
+ ret = (int)npage;
+ break;
+ }
+
+ /* Map it! */
+ ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage,
+ dma->prot);
+ if (ret) {
+ __vfio_unpin_pages_remote(iommu, pfn, npage, dma->prot,
+ true);
+ break;
+ }
+
+ size -= npage << PAGE_SHIFT;
+ dma->size += npage << PAGE_SHIFT;
+ }
+
+ dma->iommu_mapped = true;
+
+ if (ret)
+ vfio_remove_dma(iommu, dma);
+
+ return ret;
+}
+
static int vfio_dma_do_map(struct vfio_iommu *iommu,
struct vfio_iommu_type1_dma_map *map)
{
dma_addr_t iova = map->iova;
unsigned long vaddr = map->vaddr;
size_t size = map->size;
- long npage;
int ret = 0, prot = 0;
uint64_t mask;
struct vfio_dma *dma;
- unsigned long pfn;
/* Verify that none of our __u64 fields overflow */
if (map->size != size || map->vaddr != vaddr || map->iova != iova)
@@ -622,29 +993,11 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
/* Insert zero-sized and grow as we map chunks of it */
vfio_link_dma(iommu, dma);
- while (size) {
- /* Pin a contiguous chunk of memory */
- npage = vfio_pin_pages(vaddr + dma->size,
- size >> PAGE_SHIFT, prot, &pfn);
- if (npage <= 0) {
- WARN_ON(!npage);
- ret = (int)npage;
- break;
- }
-
- /* Map it! */
- ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage, prot);
- if (ret) {
- vfio_unpin_pages(pfn, npage, prot, true);
- break;
- }
-
- size -= npage << PAGE_SHIFT;
- dma->size += npage << PAGE_SHIFT;
- }
-
- if (ret)
- vfio_remove_dma(iommu, dma);
+ /* Don't pin and map if container doesn't contain IOMMU capable domain*/
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
+ dma->size = size;
+ else
+ ret = vfio_pin_map_dma(iommu, dma, size);
mutex_unlock(&iommu->lock);
return ret;
@@ -673,10 +1026,6 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
d = list_first_entry(&iommu->domain_list, struct vfio_domain, next);
n = rb_first(&iommu->dma_list);
- /* If there's not a domain, there better not be any mappings */
- if (WARN_ON(n && !d))
- return -EINVAL;
-
for (; n; n = rb_next(n)) {
struct vfio_dma *dma;
dma_addr_t iova;
@@ -685,20 +1034,43 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
iova = dma->iova;
while (iova < dma->iova + dma->size) {
- phys_addr_t phys = iommu_iova_to_phys(d->domain, iova);
+ phys_addr_t phys;
size_t size;
- if (WARN_ON(!phys)) {
- iova += PAGE_SIZE;
- continue;
- }
+ if (dma->iommu_mapped) {
+ phys = iommu_iova_to_phys(d->domain, iova);
- size = PAGE_SIZE;
+ if (WARN_ON(!phys)) {
+ iova += PAGE_SIZE;
+ continue;
+ }
- while (iova + size < dma->iova + dma->size &&
- phys + size == iommu_iova_to_phys(d->domain,
+ size = PAGE_SIZE;
+
+ while (iova + size < dma->iova + dma->size &&
+ phys + size == iommu_iova_to_phys(d->domain,
iova + size))
- size += PAGE_SIZE;
+ size += PAGE_SIZE;
+ } else {
+ unsigned long pfn;
+ unsigned long vaddr = dma->vaddr +
+ (iova - dma->iova);
+ size_t n = dma->iova + dma->size - iova;
+ long npage;
+
+ npage = __vfio_pin_pages_remote(iommu, vaddr,
+ n >> PAGE_SHIFT,
+ dma->prot,
+ &pfn);
+ if (npage <= 0) {
+ WARN_ON(!npage);
+ ret = (int)npage;
+ return ret;
+ }
+
+ phys = pfn << PAGE_SHIFT;
+ size = npage << PAGE_SHIFT;
+ }
ret = iommu_map(domain->domain, iova, phys,
size, dma->prot | domain->prot);
@@ -707,6 +1079,8 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
iova += size;
}
+
+ dma->iommu_mapped = true;
}
return 0;
@@ -764,7 +1138,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
struct vfio_iommu *iommu = iommu_data;
struct vfio_group *group;
struct vfio_domain *domain, *d;
- struct bus_type *bus = NULL;
+ struct bus_type *bus = NULL, *mdev_bus;
int ret;
mutex_lock(&iommu->lock);
@@ -776,6 +1150,13 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
}
}
+ if (iommu->external_domain) {
+ if (find_iommu_group(iommu->external_domain, iommu_group)) {
+ mutex_unlock(&iommu->lock);
+ return -EINVAL;
+ }
+ }
+
group = kzalloc(sizeof(*group), GFP_KERNEL);
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!group || !domain) {
@@ -790,6 +1171,38 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
if (ret)
goto out_free;
+ mdev_bus = symbol_get(mdev_bus_type);
+
+ if (mdev_bus) {
+ if ((bus == mdev_bus) && !iommu_present(bus)) {
+ symbol_put(mdev_bus_type);
+ if (!iommu->external_domain) {
+ struct external_addr_space *addr_space;
+
+ addr_space = kzalloc(sizeof(*addr_space),
+ GFP_KERNEL);
+ if (!addr_space) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+
+ INIT_LIST_HEAD(&domain->group_list);
+ addr_space->task = current;
+ addr_space->pfn_list = RB_ROOT;
+ mutex_init(&addr_space->pfn_list_lock);
+ domain->external_addr_space = addr_space;
+ iommu->external_domain = domain;
+ } else
+ kfree(domain);
+
+ list_add(&group->next,
+ &iommu->external_domain->group_list);
+ mutex_unlock(&iommu->lock);
+ return 0;
+ }
+ symbol_put(mdev_bus_type);
+ }
+
domain->domain = iommu_domain_alloc(bus);
if (!domain->domain) {
ret = -EIO;
@@ -880,6 +1293,42 @@ static void vfio_iommu_unmap_unpin_all(struct vfio_iommu *iommu)
vfio_remove_dma(iommu, rb_entry(node, struct vfio_dma, node));
}
+static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu)
+{
+ struct vfio_domain *domain = iommu->external_domain;
+ struct vfio_dma *dma, *tdma;
+ struct rb_node *n;
+ long locked = 0, unlocked = 0;
+
+ rbtree_postorder_for_each_entry_safe(dma, tdma, &iommu->dma_list,
+ node) {
+ unlocked += vfio_unmap_unpin(iommu, dma, false);
+ }
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ n = rb_first(&domain->external_addr_space->pfn_list);
+
+ for (; n; n = rb_next(n))
+ locked++;
+
+ vfio_lock_acct(domain->external_addr_space->task, locked - unlocked);
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+}
+
+static void vfio_external_unpin_all(struct vfio_domain *domain,
+ bool do_accounting)
+{
+ struct rb_node *node;
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+ while ((node = rb_first(&domain->external_addr_space->pfn_list)))
+ vfio_unpin_pfn(domain, rb_entry(node, struct vfio_pfn, node),
+ do_accounting);
+
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+}
+
static void vfio_iommu_type1_detach_group(void *iommu_data,
struct iommu_group *iommu_group)
{
@@ -889,6 +1338,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
mutex_lock(&iommu->lock);
+ if (iommu->external_domain) {
+ domain = iommu->external_domain;
+ group = find_iommu_group(domain, iommu_group);
+ if (group) {
+ list_del(&group->next);
+ kfree(group);
+
+ if (list_empty(&domain->group_list)) {
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) {
+ vfio_external_unpin_all(domain, true);
+ vfio_iommu_unmap_unpin_all(iommu);
+ } else
+ vfio_external_unpin_all(domain, false);
+ kfree(domain);
+ iommu->external_domain = NULL;
+ }
+ goto detach_group_done;
+ }
+ }
+
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
+ goto detach_group_done;
list_for_each_entry(domain, &iommu->domain_list, next) {
group = find_iommu_group(domain, iommu_group);
@@ -899,21 +1370,27 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
list_del(&group->next);
kfree(group);
/*
- * Group ownership provides privilege, if the group
- * list is empty, the domain goes away. If it's the
- * last domain, then all the mappings go away too.
+ * Group ownership provides privilege, if the group list is
+ * empty, the domain goes away. If it's the last domain with
+ * iommu and external domain doesn't exist, then all the
+ * mappings go away too. If it's the last domain with iommu and
+ * external domain exist, update accounting
*/
if (list_empty(&domain->group_list)) {
- if (list_is_singular(&iommu->domain_list))
- vfio_iommu_unmap_unpin_all(iommu);
+ if (list_is_singular(&iommu->domain_list)) {
+ if (!iommu->external_domain)
+ vfio_iommu_unmap_unpin_all(iommu);
+ else
+ vfio_iommu_unmap_unpin_reaccount(iommu);
+ }
iommu_domain_free(domain->domain);
list_del(&domain->next);
kfree(domain);
}
- goto done;
+ break;
}
-done:
+detach_group_done:
mutex_unlock(&iommu->lock);
}
@@ -945,23 +1422,40 @@ static void *vfio_iommu_type1_open(unsigned long arg)
return iommu;
}
+static void vfio_release_domain(struct vfio_domain *domain)
+{
+ struct vfio_group *group, *group_tmp;
+
+ list_for_each_entry_safe(group, group_tmp,
+ &domain->group_list, next) {
+ if (!domain->external_addr_space)
+ iommu_detach_group(domain->domain, group->iommu_group);
+ list_del(&group->next);
+ kfree(group);
+ }
+
+ if (domain->external_addr_space)
+ vfio_external_unpin_all(domain, false);
+ else
+ iommu_domain_free(domain->domain);
+}
+
static void vfio_iommu_type1_release(void *iommu_data)
{
struct vfio_iommu *iommu = iommu_data;
struct vfio_domain *domain, *domain_tmp;
- struct vfio_group *group, *group_tmp;
+
+ if (iommu->external_domain) {
+ vfio_release_domain(iommu->external_domain);
+ kfree(iommu->external_domain);
+ iommu->external_domain = NULL;
+ }
vfio_iommu_unmap_unpin_all(iommu);
list_for_each_entry_safe(domain, domain_tmp,
&iommu->domain_list, next) {
- list_for_each_entry_safe(group, group_tmp,
- &domain->group_list, next) {
- iommu_detach_group(domain->domain, group->iommu_group);
- list_del(&group->next);
- kfree(group);
- }
- iommu_domain_free(domain->domain);
+ vfio_release_domain(domain);
list_del(&domain->next);
kfree(domain);
}
@@ -1069,6 +1563,8 @@ static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
.ioctl = vfio_iommu_type1_ioctl,
.attach_group = vfio_iommu_type1_attach_group,
.detach_group = vfio_iommu_type1_detach_group,
+ .pin_pages = vfio_iommu_type1_pin_pages,
+ .unpin_pages = vfio_iommu_type1_unpin_pages,
};
static int __init vfio_iommu_type1_init(void)
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 09/19] vfio iommu type1: Add support for mediated devices
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
VFIO IOMMU drivers are designed for the devices which are IOMMU capable.
Mediated device only uses IOMMU APIs, the underlying hardware can be
managed by an IOMMU domain.
Aim of this change is:
- To use most of the code of TYPE1 IOMMU driver for mediated devices
- To support direct assigned device and mediated device in single module
This change adds pin and unpin support for mediated device to TYPE1 IOMMU
backend module. More details:
- When iommu_group of mediated devices is attached, task structure is
cached which is used later to pin pages and page accounting.
- It keeps track of pinned pages for mediated domain. This data is used to
verify unpinning request and to unpin remaining pages while detaching, if
there are any.
- Used existing mechanism for page accounting. If iommu capable domain
exist in the container then all pages are already pinned and accounted.
Accouting for mdev device is only done if there is no iommu capable
domain in the container.
- Page accouting is updated on hot plug and unplug mdev device and pass
through device.
Tested by assigning below combinations of devices to a single VM:
- GPU pass through only
- vGPU device only
- One GPU pass through and one vGPU device
- Linux VM hot plug and unplug vGPU device while GPU pass through device
exist
- Linux VM hot plug and unplug GPU pass through device while vGPU device
exist
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I295d6f0f2e0579b8d9882bfd8fd5a4194b97bd9a
---
drivers/vfio/vfio_iommu_type1.c | 646 +++++++++++++++++++++++++++++++++++-----
1 file changed, 571 insertions(+), 75 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 861ac2a1b0c3..5add11a147e1 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -36,6 +36,7 @@
#include <linux/uaccess.h>
#include <linux/vfio.h>
#include <linux/workqueue.h>
+#include <linux/mdev.h>
#define DRIVER_VERSION "0.2"
#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
@@ -55,18 +56,26 @@ MODULE_PARM_DESC(disable_hugepages,
struct vfio_iommu {
struct list_head domain_list;
+ struct vfio_domain *external_domain; /* domain for external user */
struct mutex lock;
struct rb_root dma_list;
bool v2;
bool nesting;
};
+struct external_addr_space {
+ struct task_struct *task;
+ struct rb_root pfn_list; /* pinned Host pfn list */
+ struct mutex pfn_list_lock; /* mutex for pfn_list */
+};
+
struct vfio_domain {
- struct iommu_domain *domain;
- struct list_head next;
- struct list_head group_list;
- int prot; /* IOMMU_CACHE */
- bool fgsp; /* Fine-grained super pages */
+ struct iommu_domain *domain;
+ struct list_head next;
+ struct list_head group_list;
+ struct external_addr_space *external_addr_space;
+ int prot; /* IOMMU_CACHE */
+ bool fgsp; /* Fine-grained super pages */
};
struct vfio_dma {
@@ -75,6 +84,7 @@ struct vfio_dma {
unsigned long vaddr; /* Process virtual addr */
size_t size; /* Map size (bytes) */
int prot; /* IOMMU_READ/WRITE */
+ bool iommu_mapped;
};
struct vfio_group {
@@ -83,6 +93,21 @@ struct vfio_group {
};
/*
+ * Guest RAM pinning working set or DMA target
+ */
+struct vfio_pfn {
+ struct rb_node node;
+ unsigned long vaddr; /* virtual addr */
+ dma_addr_t iova; /* IOVA */
+ unsigned long pfn; /* Host pfn */
+ int prot;
+ atomic_t ref_count;
+};
+
+#define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \
+ (!list_empty(&iommu->domain_list))
+
+/*
* This code handles mapping and unmapping of user data buffers
* into DMA'ble space using the IOMMU
*/
@@ -130,6 +155,101 @@ static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
rb_erase(&old->node, &iommu->dma_list);
}
+/*
+ * Helper Functions for host pfn list
+ */
+
+static struct vfio_pfn *vfio_find_pfn(struct vfio_domain *domain,
+ unsigned long pfn)
+{
+ struct rb_node *node;
+ struct vfio_pfn *vpfn;
+
+ node = domain->external_addr_space->pfn_list.rb_node;
+
+ while (node) {
+ vpfn = rb_entry(node, struct vfio_pfn, node);
+
+ if (pfn < vpfn->pfn)
+ node = node->rb_left;
+ else if (pfn > vpfn->pfn)
+ node = node->rb_right;
+ else
+ return vpfn;
+ }
+
+ return NULL;
+}
+
+static void vfio_link_pfn(struct vfio_domain *domain, struct vfio_pfn *new)
+{
+ struct rb_node **link, *parent = NULL;
+ struct vfio_pfn *vpfn;
+
+ link = &domain->external_addr_space->pfn_list.rb_node;
+ while (*link) {
+ parent = *link;
+ vpfn = rb_entry(parent, struct vfio_pfn, node);
+
+ if (new->pfn < vpfn->pfn)
+ link = &(*link)->rb_left;
+ else
+ link = &(*link)->rb_right;
+ }
+
+ rb_link_node(&new->node, parent, link);
+ rb_insert_color(&new->node, &domain->external_addr_space->pfn_list);
+}
+
+static void vfio_unlink_pfn(struct vfio_domain *domain, struct vfio_pfn *old)
+{
+ rb_erase(&old->node, &domain->external_addr_space->pfn_list);
+}
+
+static int vfio_add_to_pfn_list(struct vfio_domain *domain, unsigned long vaddr,
+ dma_addr_t iova, unsigned long pfn, int prot)
+{
+ struct vfio_pfn *vpfn;
+
+ vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
+ if (!vpfn)
+ return -ENOMEM;
+
+ vpfn->vaddr = vaddr;
+ vpfn->iova = iova;
+ vpfn->pfn = pfn;
+ vpfn->prot = prot;
+ atomic_set(&vpfn->ref_count, 1);
+ vfio_link_pfn(domain, vpfn);
+ return 0;
+}
+
+static void vfio_remove_from_pfn_list(struct vfio_domain *domain,
+ struct vfio_pfn *vpfn)
+{
+ vfio_unlink_pfn(domain, vpfn);
+ kfree(vpfn);
+}
+
+static int vfio_pfn_account(struct vfio_iommu *iommu, unsigned long pfn)
+{
+ struct vfio_pfn *p;
+ struct vfio_domain *domain = iommu->external_domain;
+ int ret = 1;
+
+ if (!domain)
+ return 1;
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ p = vfio_find_pfn(domain, pfn);
+ if (p)
+ ret = 0;
+
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+ return ret;
+}
+
struct vwork {
struct mm_struct *mm;
long npage;
@@ -270,12 +390,13 @@ static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
* the iommu can only map chunks of consecutive pfns anyway, so get the
* first page and all consecutive pages with the same locking.
*/
-static long vfio_pin_pages(unsigned long vaddr, long npage,
- int prot, unsigned long *pfn_base)
+static long __vfio_pin_pages_remote(struct vfio_iommu *iommu,
+ unsigned long vaddr, long npage,
+ int prot, unsigned long *pfn_base)
{
unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
bool lock_cap = capable(CAP_IPC_LOCK);
- long ret, i;
+ long ret, i, lock_acct = 0;
bool rsvd;
if (!current->mm)
@@ -285,9 +406,11 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
if (ret)
return ret;
+ lock_acct = vfio_pfn_account(iommu, *pfn_base);
+
rsvd = is_invalid_reserved_pfn(*pfn_base);
- if (!rsvd && !lock_cap && current->mm->locked_vm + 1 > limit) {
+ if (!rsvd && !lock_cap && current->mm->locked_vm + lock_acct > limit) {
put_pfn(*pfn_base, prot);
pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
limit << PAGE_SHIFT);
@@ -314,8 +437,10 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
break;
}
+ lock_acct += vfio_pfn_account(iommu, pfn);
+
if (!rsvd && !lock_cap &&
- current->mm->locked_vm + i + 1 > limit) {
+ current->mm->locked_vm + lock_acct > limit) {
put_pfn(pfn, prot);
pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
__func__, limit << PAGE_SHIFT);
@@ -329,14 +454,19 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
return i;
}
-static long vfio_unpin_pages(unsigned long pfn, long npage,
- int prot, bool do_accounting)
+static long __vfio_unpin_pages_remote(struct vfio_iommu *iommu,
+ unsigned long pfn, long npage, int prot,
+ bool do_accounting)
{
- unsigned long unlocked = 0;
+ unsigned long unlocked = 0, unlock_acct = 0;
long i;
- for (i = 0; i < npage; i++)
+ for (i = 0; i < npage; i++) {
+ if (do_accounting)
+ unlock_acct += vfio_pfn_account(iommu, pfn);
+
unlocked += put_pfn(pfn++, prot);
+ }
if (do_accounting)
vfio_lock_acct(current, -unlocked);
@@ -344,14 +474,208 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
return unlocked;
}
-static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
+static long __vfio_pin_page_external(struct vfio_domain *domain,
+ unsigned long vaddr, int prot,
+ unsigned long *pfn_base,
+ bool do_accounting)
+{
+ unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ bool lock_cap = capable(CAP_IPC_LOCK);
+ long ret;
+ bool rsvd;
+ struct task_struct *task = domain->external_addr_space->task;
+
+ if (!task->mm)
+ return -ENODEV;
+
+ ret = vaddr_get_pfn(task->mm, vaddr, prot, pfn_base);
+ if (ret)
+ return ret;
+
+ rsvd = is_invalid_reserved_pfn(*pfn_base);
+
+ if (!rsvd && !lock_cap && task->mm->locked_vm + 1 > limit) {
+ put_pfn(*pfn_base, prot);
+ pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
+ limit << PAGE_SHIFT);
+ return -ENOMEM;
+ }
+
+ if (!rsvd && do_accounting)
+ vfio_lock_acct(task, 1);
+
+ return 1;
+}
+
+static void __vfio_unpin_page_external(struct vfio_domain *domain,
+ unsigned long pfn, int prot,
+ bool do_accounting)
+{
+ put_pfn(pfn, prot);
+
+ if (do_accounting)
+ vfio_lock_acct(domain->external_addr_space->task, -1);
+}
+
+static int vfio_unpin_pfn(struct vfio_domain *domain,
+ struct vfio_pfn *vpfn, bool do_accounting)
+{
+ __vfio_unpin_page_external(domain, vpfn->pfn, vpfn->prot,
+ do_accounting);
+
+ if (atomic_dec_and_test(&vpfn->ref_count))
+ vfio_remove_from_pfn_list(domain, vpfn);
+
+ return 1;
+}
+
+static long vfio_iommu_type1_pin_pages(void *iommu_data,
+ unsigned long *user_pfn,
+ long npage, int prot,
+ unsigned long *phys_pfn)
+{
+ struct vfio_iommu *iommu = iommu_data;
+ struct vfio_domain *domain;
+ struct external_addr_space *addr_space;
+ int i, j, ret;
+ long retpage;
+ unsigned long remote_vaddr;
+ unsigned long *pfn = phys_pfn;
+ struct vfio_dma *dma;
+ bool do_accounting;
+
+ if (!iommu || !user_pfn || !phys_pfn)
+ return -EINVAL;
+
+ mutex_lock(&iommu->lock);
+
+ if (!iommu->external_domain) {
+ ret = -EINVAL;
+ goto pin_done;
+ }
+
+ domain = iommu->external_domain;
+ addr_space = domain->external_addr_space;
+ /*
+ * If iommu capable domain exist in the container then all pages are
+ * already pinned and accounted. Accouting should be done if there is no
+ * iommu capable domain in the container.
+ */
+ do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
+
+ for (i = 0; i < npage; i++) {
+ struct vfio_pfn *p;
+ dma_addr_t iova;
+
+ iova = user_pfn[i] << PAGE_SHIFT;
+
+ dma = vfio_find_dma(iommu, iova, 0);
+ if (!dma) {
+ ret = -EINVAL;
+ goto pin_unwind;
+ }
+
+ remote_vaddr = dma->vaddr + iova - dma->iova;
+
+ retpage = __vfio_pin_page_external(domain, remote_vaddr, prot,
+ &pfn[i], do_accounting);
+ if (retpage <= 0) {
+ WARN_ON(!retpage);
+ ret = (int)retpage;
+ goto pin_unwind;
+ }
+
+ mutex_lock(&addr_space->pfn_list_lock);
+
+ /* search if pfn exist */
+ p = vfio_find_pfn(domain, pfn[i]);
+ if (p) {
+ atomic_inc(&p->ref_count);
+ mutex_unlock(&addr_space->pfn_list_lock);
+ continue;
+ }
+
+ ret = vfio_add_to_pfn_list(domain, remote_vaddr, iova,
+ pfn[i], prot);
+ mutex_unlock(&addr_space->pfn_list_lock);
+
+ if (ret) {
+ __vfio_unpin_page_external(domain, pfn[i], prot,
+ do_accounting);
+ goto pin_unwind;
+ }
+ }
+
+ ret = i;
+ goto pin_done;
+
+pin_unwind:
+ pfn[i] = 0;
+ mutex_lock(&addr_space->pfn_list_lock);
+ for (j = 0; j < i; j++) {
+ struct vfio_pfn *p;
+
+ p = vfio_find_pfn(domain, pfn[j]);
+ if (p)
+ vfio_unpin_pfn(domain, p, do_accounting);
+
+ pfn[j] = 0;
+ }
+ mutex_unlock(&addr_space->pfn_list_lock);
+
+pin_done:
+ mutex_unlock(&iommu->lock);
+ return ret;
+}
+
+static long vfio_iommu_type1_unpin_pages(void *iommu_data, unsigned long *pfn,
+ long npage)
+{
+ struct vfio_iommu *iommu = iommu_data;
+ struct vfio_domain *domain = NULL;
+ bool do_accounting;
+ long unlocked = 0;
+ int i;
+
+ if (!iommu || !pfn)
+ return -EINVAL;
+
+ mutex_lock(&iommu->lock);
+
+ domain = iommu->external_domain;
+
+ do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ for (i = 0; i < npage; i++) {
+ struct vfio_pfn *p;
+
+ /* verify if pfn exist in pfn_list */
+ p = vfio_find_pfn(domain, pfn[i]);
+ if (p)
+ unlocked += vfio_unpin_pfn(domain, p, do_accounting);
+
+ }
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+
+ mutex_unlock(&iommu->lock);
+ return unlocked;
+}
+
+static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
+ bool do_accounting)
{
dma_addr_t iova = dma->iova, end = dma->iova + dma->size;
struct vfio_domain *domain, *d;
long unlocked = 0;
if (!dma->size)
- return;
+ return 0;
+
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
+ return 0;
+
/*
* We use the IOMMU to track the physical addresses, otherwise we'd
* need a much more complicated tracking system. Unfortunately that
@@ -393,20 +717,27 @@ static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
if (WARN_ON(!unmapped))
break;
- unlocked += vfio_unpin_pages(phys >> PAGE_SHIFT,
- unmapped >> PAGE_SHIFT,
- dma->prot, false);
+ unlocked += __vfio_unpin_pages_remote(iommu, phys >> PAGE_SHIFT,
+ unmapped >> PAGE_SHIFT,
+ dma->prot, false);
iova += unmapped;
cond_resched();
}
- vfio_lock_acct(current, -unlocked);
+ dma->iommu_mapped = false;
+
+ if (do_accounting) {
+ vfio_lock_acct(current, -unlocked);
+ return 0;
+ }
+
+ return unlocked;
}
static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
{
- vfio_unmap_unpin(iommu, dma);
+ vfio_unmap_unpin(iommu, dma, true);
vfio_unlink_dma(iommu, dma);
kfree(dma);
}
@@ -569,17 +900,57 @@ unwind:
return ret;
}
+static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma,
+ size_t map_size)
+{
+ dma_addr_t iova = dma->iova;
+ unsigned long vaddr = dma->vaddr;
+ size_t size = map_size;
+ long npage;
+ unsigned long pfn;
+ int ret = 0;
+
+ while (size) {
+ /* Pin a contiguous chunk of memory */
+ npage = __vfio_pin_pages_remote(iommu, vaddr + dma->size,
+ size >> PAGE_SHIFT, dma->prot,
+ &pfn);
+ if (npage <= 0) {
+ WARN_ON(!npage);
+ ret = (int)npage;
+ break;
+ }
+
+ /* Map it! */
+ ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage,
+ dma->prot);
+ if (ret) {
+ __vfio_unpin_pages_remote(iommu, pfn, npage, dma->prot,
+ true);
+ break;
+ }
+
+ size -= npage << PAGE_SHIFT;
+ dma->size += npage << PAGE_SHIFT;
+ }
+
+ dma->iommu_mapped = true;
+
+ if (ret)
+ vfio_remove_dma(iommu, dma);
+
+ return ret;
+}
+
static int vfio_dma_do_map(struct vfio_iommu *iommu,
struct vfio_iommu_type1_dma_map *map)
{
dma_addr_t iova = map->iova;
unsigned long vaddr = map->vaddr;
size_t size = map->size;
- long npage;
int ret = 0, prot = 0;
uint64_t mask;
struct vfio_dma *dma;
- unsigned long pfn;
/* Verify that none of our __u64 fields overflow */
if (map->size != size || map->vaddr != vaddr || map->iova != iova)
@@ -622,29 +993,11 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
/* Insert zero-sized and grow as we map chunks of it */
vfio_link_dma(iommu, dma);
- while (size) {
- /* Pin a contiguous chunk of memory */
- npage = vfio_pin_pages(vaddr + dma->size,
- size >> PAGE_SHIFT, prot, &pfn);
- if (npage <= 0) {
- WARN_ON(!npage);
- ret = (int)npage;
- break;
- }
-
- /* Map it! */
- ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage, prot);
- if (ret) {
- vfio_unpin_pages(pfn, npage, prot, true);
- break;
- }
-
- size -= npage << PAGE_SHIFT;
- dma->size += npage << PAGE_SHIFT;
- }
-
- if (ret)
- vfio_remove_dma(iommu, dma);
+ /* Don't pin and map if container doesn't contain IOMMU capable domain*/
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
+ dma->size = size;
+ else
+ ret = vfio_pin_map_dma(iommu, dma, size);
mutex_unlock(&iommu->lock);
return ret;
@@ -673,10 +1026,6 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
d = list_first_entry(&iommu->domain_list, struct vfio_domain, next);
n = rb_first(&iommu->dma_list);
- /* If there's not a domain, there better not be any mappings */
- if (WARN_ON(n && !d))
- return -EINVAL;
-
for (; n; n = rb_next(n)) {
struct vfio_dma *dma;
dma_addr_t iova;
@@ -685,20 +1034,43 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
iova = dma->iova;
while (iova < dma->iova + dma->size) {
- phys_addr_t phys = iommu_iova_to_phys(d->domain, iova);
+ phys_addr_t phys;
size_t size;
- if (WARN_ON(!phys)) {
- iova += PAGE_SIZE;
- continue;
- }
+ if (dma->iommu_mapped) {
+ phys = iommu_iova_to_phys(d->domain, iova);
- size = PAGE_SIZE;
+ if (WARN_ON(!phys)) {
+ iova += PAGE_SIZE;
+ continue;
+ }
- while (iova + size < dma->iova + dma->size &&
- phys + size == iommu_iova_to_phys(d->domain,
+ size = PAGE_SIZE;
+
+ while (iova + size < dma->iova + dma->size &&
+ phys + size == iommu_iova_to_phys(d->domain,
iova + size))
- size += PAGE_SIZE;
+ size += PAGE_SIZE;
+ } else {
+ unsigned long pfn;
+ unsigned long vaddr = dma->vaddr +
+ (iova - dma->iova);
+ size_t n = dma->iova + dma->size - iova;
+ long npage;
+
+ npage = __vfio_pin_pages_remote(iommu, vaddr,
+ n >> PAGE_SHIFT,
+ dma->prot,
+ &pfn);
+ if (npage <= 0) {
+ WARN_ON(!npage);
+ ret = (int)npage;
+ return ret;
+ }
+
+ phys = pfn << PAGE_SHIFT;
+ size = npage << PAGE_SHIFT;
+ }
ret = iommu_map(domain->domain, iova, phys,
size, dma->prot | domain->prot);
@@ -707,6 +1079,8 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
iova += size;
}
+
+ dma->iommu_mapped = true;
}
return 0;
@@ -764,7 +1138,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
struct vfio_iommu *iommu = iommu_data;
struct vfio_group *group;
struct vfio_domain *domain, *d;
- struct bus_type *bus = NULL;
+ struct bus_type *bus = NULL, *mdev_bus;
int ret;
mutex_lock(&iommu->lock);
@@ -776,6 +1150,13 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
}
}
+ if (iommu->external_domain) {
+ if (find_iommu_group(iommu->external_domain, iommu_group)) {
+ mutex_unlock(&iommu->lock);
+ return -EINVAL;
+ }
+ }
+
group = kzalloc(sizeof(*group), GFP_KERNEL);
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!group || !domain) {
@@ -790,6 +1171,38 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
if (ret)
goto out_free;
+ mdev_bus = symbol_get(mdev_bus_type);
+
+ if (mdev_bus) {
+ if ((bus == mdev_bus) && !iommu_present(bus)) {
+ symbol_put(mdev_bus_type);
+ if (!iommu->external_domain) {
+ struct external_addr_space *addr_space;
+
+ addr_space = kzalloc(sizeof(*addr_space),
+ GFP_KERNEL);
+ if (!addr_space) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+
+ INIT_LIST_HEAD(&domain->group_list);
+ addr_space->task = current;
+ addr_space->pfn_list = RB_ROOT;
+ mutex_init(&addr_space->pfn_list_lock);
+ domain->external_addr_space = addr_space;
+ iommu->external_domain = domain;
+ } else
+ kfree(domain);
+
+ list_add(&group->next,
+ &iommu->external_domain->group_list);
+ mutex_unlock(&iommu->lock);
+ return 0;
+ }
+ symbol_put(mdev_bus_type);
+ }
+
domain->domain = iommu_domain_alloc(bus);
if (!domain->domain) {
ret = -EIO;
@@ -880,6 +1293,42 @@ static void vfio_iommu_unmap_unpin_all(struct vfio_iommu *iommu)
vfio_remove_dma(iommu, rb_entry(node, struct vfio_dma, node));
}
+static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu)
+{
+ struct vfio_domain *domain = iommu->external_domain;
+ struct vfio_dma *dma, *tdma;
+ struct rb_node *n;
+ long locked = 0, unlocked = 0;
+
+ rbtree_postorder_for_each_entry_safe(dma, tdma, &iommu->dma_list,
+ node) {
+ unlocked += vfio_unmap_unpin(iommu, dma, false);
+ }
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ n = rb_first(&domain->external_addr_space->pfn_list);
+
+ for (; n; n = rb_next(n))
+ locked++;
+
+ vfio_lock_acct(domain->external_addr_space->task, locked - unlocked);
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+}
+
+static void vfio_external_unpin_all(struct vfio_domain *domain,
+ bool do_accounting)
+{
+ struct rb_node *node;
+
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+ while ((node = rb_first(&domain->external_addr_space->pfn_list)))
+ vfio_unpin_pfn(domain, rb_entry(node, struct vfio_pfn, node),
+ do_accounting);
+
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+}
+
static void vfio_iommu_type1_detach_group(void *iommu_data,
struct iommu_group *iommu_group)
{
@@ -889,6 +1338,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
mutex_lock(&iommu->lock);
+ if (iommu->external_domain) {
+ domain = iommu->external_domain;
+ group = find_iommu_group(domain, iommu_group);
+ if (group) {
+ list_del(&group->next);
+ kfree(group);
+
+ if (list_empty(&domain->group_list)) {
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) {
+ vfio_external_unpin_all(domain, true);
+ vfio_iommu_unmap_unpin_all(iommu);
+ } else
+ vfio_external_unpin_all(domain, false);
+ kfree(domain);
+ iommu->external_domain = NULL;
+ }
+ goto detach_group_done;
+ }
+ }
+
+ if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
+ goto detach_group_done;
list_for_each_entry(domain, &iommu->domain_list, next) {
group = find_iommu_group(domain, iommu_group);
@@ -899,21 +1370,27 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
list_del(&group->next);
kfree(group);
/*
- * Group ownership provides privilege, if the group
- * list is empty, the domain goes away. If it's the
- * last domain, then all the mappings go away too.
+ * Group ownership provides privilege, if the group list is
+ * empty, the domain goes away. If it's the last domain with
+ * iommu and external domain doesn't exist, then all the
+ * mappings go away too. If it's the last domain with iommu and
+ * external domain exist, update accounting
*/
if (list_empty(&domain->group_list)) {
- if (list_is_singular(&iommu->domain_list))
- vfio_iommu_unmap_unpin_all(iommu);
+ if (list_is_singular(&iommu->domain_list)) {
+ if (!iommu->external_domain)
+ vfio_iommu_unmap_unpin_all(iommu);
+ else
+ vfio_iommu_unmap_unpin_reaccount(iommu);
+ }
iommu_domain_free(domain->domain);
list_del(&domain->next);
kfree(domain);
}
- goto done;
+ break;
}
-done:
+detach_group_done:
mutex_unlock(&iommu->lock);
}
@@ -945,23 +1422,40 @@ static void *vfio_iommu_type1_open(unsigned long arg)
return iommu;
}
+static void vfio_release_domain(struct vfio_domain *domain)
+{
+ struct vfio_group *group, *group_tmp;
+
+ list_for_each_entry_safe(group, group_tmp,
+ &domain->group_list, next) {
+ if (!domain->external_addr_space)
+ iommu_detach_group(domain->domain, group->iommu_group);
+ list_del(&group->next);
+ kfree(group);
+ }
+
+ if (domain->external_addr_space)
+ vfio_external_unpin_all(domain, false);
+ else
+ iommu_domain_free(domain->domain);
+}
+
static void vfio_iommu_type1_release(void *iommu_data)
{
struct vfio_iommu *iommu = iommu_data;
struct vfio_domain *domain, *domain_tmp;
- struct vfio_group *group, *group_tmp;
+
+ if (iommu->external_domain) {
+ vfio_release_domain(iommu->external_domain);
+ kfree(iommu->external_domain);
+ iommu->external_domain = NULL;
+ }
vfio_iommu_unmap_unpin_all(iommu);
list_for_each_entry_safe(domain, domain_tmp,
&iommu->domain_list, next) {
- list_for_each_entry_safe(group, group_tmp,
- &domain->group_list, next) {
- iommu_detach_group(domain->domain, group->iommu_group);
- list_del(&group->next);
- kfree(group);
- }
- iommu_domain_free(domain->domain);
+ vfio_release_domain(domain);
list_del(&domain->next);
kfree(domain);
}
@@ -1069,6 +1563,8 @@ static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
.ioctl = vfio_iommu_type1_ioctl,
.attach_group = vfio_iommu_type1_attach_group,
.detach_group = vfio_iommu_type1_detach_group,
+ .pin_pages = vfio_iommu_type1_pin_pages,
+ .unpin_pages = vfio_iommu_type1_unpin_pages,
};
static int __init vfio_iommu_type1_init(void)
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
about DMA_UNMAP.
Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
Vendor driver should register notifer using these APIs.
Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
mappings.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
---
drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
include/linux/vfio.h | 11 +++++
3 files changed, 163 insertions(+), 10 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 28b50ca14c52..ff05ac6b1e90 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1891,6 +1891,79 @@ err_unpin_pages:
}
EXPORT_SYMBOL(vfio_unpin_pages);
+int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !nb)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_register_nb;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->register_notifier))
+ ret = driver->ops->register_notifier(container->iommu_data, nb);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_register_nb:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_register_notifier);
+
+int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !nb)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_unregister_nb;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->unregister_notifier))
+ ret = driver->ops->unregister_notifier(container->iommu_data,
+ nb);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_unregister_nb:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_unregister_notifier);
+
/**
* Module/class support
*/
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 5add11a147e1..a4bd331ac0fd 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -37,6 +37,7 @@
#include <linux/vfio.h>
#include <linux/workqueue.h>
#include <linux/mdev.h>
+#include <linux/notifier.h>
#define DRIVER_VERSION "0.2"
#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
@@ -59,6 +60,7 @@ struct vfio_iommu {
struct vfio_domain *external_domain; /* domain for external user */
struct mutex lock;
struct rb_root dma_list;
+ struct blocking_notifier_head notifier;
bool v2;
bool nesting;
};
@@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
mutex_lock(&iommu->lock);
- if (!iommu->external_domain) {
+ /* Fail if notifier list is empty */
+ if ((!iommu->external_domain) || (!iommu->notifier.head)) {
ret = -EINVAL;
goto pin_done;
}
@@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
return bitmap;
}
+/*
+ * This function finds pfn in domain->external_addr_space->pfn_list for given
+ * iova range. If pfn exist, notify pfn to registered notifier list. On
+ * receiving notifier callback, vendor driver should invalidate the mapping and
+ * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
+ * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
+ * searching for next vfio_pfn in rb tree, start search from first node again.
+ * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
+ * from rb tree and so in next search vfio_pfn would be same as previous
+ * vfio_pfn. In that case, exit from loop.
+ */
+static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
+ struct vfio_iommu_type1_dma_unmap *unmap)
+{
+ struct vfio_domain *domain = iommu->external_domain;
+ struct rb_node *n;
+ struct vfio_pfn *vpfn = NULL, *prev_vpfn;
+
+ do {
+ prev_vpfn = vpfn;
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ n = rb_first(&domain->external_addr_space->pfn_list);
+
+ for (; n; n = rb_next(n), vpfn = NULL) {
+ vpfn = rb_entry(n, struct vfio_pfn, node);
+
+ if ((vpfn->iova >= unmap->iova) &&
+ (vpfn->iova < unmap->iova + unmap->size))
+ break;
+ }
+
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+
+ /* Notify any listeners about DMA_UNMAP */
+ if (vpfn)
+ blocking_notifier_call_chain(&iommu->notifier,
+ VFIO_IOMMU_NOTIFY_DMA_UNMAP,
+ &vpfn->pfn);
+ } while (vpfn && (prev_vpfn != vpfn));
+
+ WARN_ON(vpfn);
+}
+
static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
struct vfio_iommu_type1_dma_unmap *unmap)
{
@@ -844,6 +891,9 @@ unlock:
/* Report how much was unmapped */
unmap->size = unmapped;
+ if (unmapped && iommu->external_domain)
+ vfio_notifier_call_chain(iommu, unmap);
+
return ret;
}
@@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
INIT_LIST_HEAD(&iommu->domain_list);
iommu->dma_list = RB_ROOT;
mutex_init(&iommu->lock);
+ BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
return iommu;
}
@@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
return -ENOTTY;
}
+static int vfio_iommu_type1_register_notifier(void *iommu_data,
+ struct notifier_block *nb)
+{
+ struct vfio_iommu *iommu = iommu_data;
+
+ return blocking_notifier_chain_register(&iommu->notifier, nb);
+}
+
+static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
+ struct notifier_block *nb)
+{
+ struct vfio_iommu *iommu = iommu_data;
+
+ return blocking_notifier_chain_unregister(&iommu->notifier, nb);
+}
+
static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
- .name = "vfio-iommu-type1",
- .owner = THIS_MODULE,
- .open = vfio_iommu_type1_open,
- .release = vfio_iommu_type1_release,
- .ioctl = vfio_iommu_type1_ioctl,
- .attach_group = vfio_iommu_type1_attach_group,
- .detach_group = vfio_iommu_type1_detach_group,
- .pin_pages = vfio_iommu_type1_pin_pages,
- .unpin_pages = vfio_iommu_type1_unpin_pages,
+ .name = "vfio-iommu-type1",
+ .owner = THIS_MODULE,
+ .open = vfio_iommu_type1_open,
+ .release = vfio_iommu_type1_release,
+ .ioctl = vfio_iommu_type1_ioctl,
+ .attach_group = vfio_iommu_type1_attach_group,
+ .detach_group = vfio_iommu_type1_detach_group,
+ .pin_pages = vfio_iommu_type1_pin_pages,
+ .unpin_pages = vfio_iommu_type1_unpin_pages,
+ .register_notifier = vfio_iommu_type1_register_notifier,
+ .unregister_notifier = vfio_iommu_type1_unregister_notifier,
};
static int __init vfio_iommu_type1_init(void)
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 0609a2052846..4c91ce8bfaeb 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
unsigned long *phys_pfn);
long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
long npage);
+ int (*register_notifier)(void *iommu_data,
+ struct notifier_block *nb);
+ int (*unregister_notifier)(void *iommu_data,
+ struct notifier_block *nb);
};
extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
@@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
long npage);
+#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
+
+extern int vfio_register_notifier(struct device *dev,
+ struct notifier_block *nb);
+
+extern int vfio_unregister_notifier(struct device *dev,
+ struct notifier_block *nb);
/*
* IRQfd - generic
*/
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
about DMA_UNMAP.
Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
Vendor driver should register notifer using these APIs.
Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
mappings.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
---
drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
include/linux/vfio.h | 11 +++++
3 files changed, 163 insertions(+), 10 deletions(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 28b50ca14c52..ff05ac6b1e90 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1891,6 +1891,79 @@ err_unpin_pages:
}
EXPORT_SYMBOL(vfio_unpin_pages);
+int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !nb)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_register_nb;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->register_notifier))
+ ret = driver->ops->register_notifier(container->iommu_data, nb);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_register_nb:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_register_notifier);
+
+int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
+{
+ struct vfio_container *container;
+ struct vfio_group *group;
+ struct vfio_iommu_driver *driver;
+ ssize_t ret;
+
+ if (!dev || !nb)
+ return -EINVAL;
+
+ group = vfio_group_get_from_dev(dev);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
+
+ ret = vfio_group_add_container_user(group);
+ if (ret)
+ goto err_unregister_nb;
+
+ container = group->container;
+ down_read(&container->group_lock);
+
+ driver = container->iommu_driver;
+ if (likely(driver && driver->ops->unregister_notifier))
+ ret = driver->ops->unregister_notifier(container->iommu_data,
+ nb);
+ else
+ ret = -EINVAL;
+
+ up_read(&container->group_lock);
+ vfio_group_try_dissolve_container(group);
+
+err_unregister_nb:
+ vfio_group_put(group);
+ return ret;
+}
+EXPORT_SYMBOL(vfio_unregister_notifier);
+
/**
* Module/class support
*/
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 5add11a147e1..a4bd331ac0fd 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -37,6 +37,7 @@
#include <linux/vfio.h>
#include <linux/workqueue.h>
#include <linux/mdev.h>
+#include <linux/notifier.h>
#define DRIVER_VERSION "0.2"
#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
@@ -59,6 +60,7 @@ struct vfio_iommu {
struct vfio_domain *external_domain; /* domain for external user */
struct mutex lock;
struct rb_root dma_list;
+ struct blocking_notifier_head notifier;
bool v2;
bool nesting;
};
@@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
mutex_lock(&iommu->lock);
- if (!iommu->external_domain) {
+ /* Fail if notifier list is empty */
+ if ((!iommu->external_domain) || (!iommu->notifier.head)) {
ret = -EINVAL;
goto pin_done;
}
@@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
return bitmap;
}
+/*
+ * This function finds pfn in domain->external_addr_space->pfn_list for given
+ * iova range. If pfn exist, notify pfn to registered notifier list. On
+ * receiving notifier callback, vendor driver should invalidate the mapping and
+ * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
+ * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
+ * searching for next vfio_pfn in rb tree, start search from first node again.
+ * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
+ * from rb tree and so in next search vfio_pfn would be same as previous
+ * vfio_pfn. In that case, exit from loop.
+ */
+static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
+ struct vfio_iommu_type1_dma_unmap *unmap)
+{
+ struct vfio_domain *domain = iommu->external_domain;
+ struct rb_node *n;
+ struct vfio_pfn *vpfn = NULL, *prev_vpfn;
+
+ do {
+ prev_vpfn = vpfn;
+ mutex_lock(&domain->external_addr_space->pfn_list_lock);
+
+ n = rb_first(&domain->external_addr_space->pfn_list);
+
+ for (; n; n = rb_next(n), vpfn = NULL) {
+ vpfn = rb_entry(n, struct vfio_pfn, node);
+
+ if ((vpfn->iova >= unmap->iova) &&
+ (vpfn->iova < unmap->iova + unmap->size))
+ break;
+ }
+
+ mutex_unlock(&domain->external_addr_space->pfn_list_lock);
+
+ /* Notify any listeners about DMA_UNMAP */
+ if (vpfn)
+ blocking_notifier_call_chain(&iommu->notifier,
+ VFIO_IOMMU_NOTIFY_DMA_UNMAP,
+ &vpfn->pfn);
+ } while (vpfn && (prev_vpfn != vpfn));
+
+ WARN_ON(vpfn);
+}
+
static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
struct vfio_iommu_type1_dma_unmap *unmap)
{
@@ -844,6 +891,9 @@ unlock:
/* Report how much was unmapped */
unmap->size = unmapped;
+ if (unmapped && iommu->external_domain)
+ vfio_notifier_call_chain(iommu, unmap);
+
return ret;
}
@@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
INIT_LIST_HEAD(&iommu->domain_list);
iommu->dma_list = RB_ROOT;
mutex_init(&iommu->lock);
+ BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
return iommu;
}
@@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
return -ENOTTY;
}
+static int vfio_iommu_type1_register_notifier(void *iommu_data,
+ struct notifier_block *nb)
+{
+ struct vfio_iommu *iommu = iommu_data;
+
+ return blocking_notifier_chain_register(&iommu->notifier, nb);
+}
+
+static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
+ struct notifier_block *nb)
+{
+ struct vfio_iommu *iommu = iommu_data;
+
+ return blocking_notifier_chain_unregister(&iommu->notifier, nb);
+}
+
static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
- .name = "vfio-iommu-type1",
- .owner = THIS_MODULE,
- .open = vfio_iommu_type1_open,
- .release = vfio_iommu_type1_release,
- .ioctl = vfio_iommu_type1_ioctl,
- .attach_group = vfio_iommu_type1_attach_group,
- .detach_group = vfio_iommu_type1_detach_group,
- .pin_pages = vfio_iommu_type1_pin_pages,
- .unpin_pages = vfio_iommu_type1_unpin_pages,
+ .name = "vfio-iommu-type1",
+ .owner = THIS_MODULE,
+ .open = vfio_iommu_type1_open,
+ .release = vfio_iommu_type1_release,
+ .ioctl = vfio_iommu_type1_ioctl,
+ .attach_group = vfio_iommu_type1_attach_group,
+ .detach_group = vfio_iommu_type1_detach_group,
+ .pin_pages = vfio_iommu_type1_pin_pages,
+ .unpin_pages = vfio_iommu_type1_unpin_pages,
+ .register_notifier = vfio_iommu_type1_register_notifier,
+ .unregister_notifier = vfio_iommu_type1_unregister_notifier,
};
static int __init vfio_iommu_type1_init(void)
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 0609a2052846..4c91ce8bfaeb 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
unsigned long *phys_pfn);
long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
long npage);
+ int (*register_notifier)(void *iommu_data,
+ struct notifier_block *nb);
+ int (*unregister_notifier)(void *iommu_data,
+ struct notifier_block *nb);
};
extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
@@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
long npage);
+#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
+
+extern int vfio_register_notifier(struct device *dev,
+ struct notifier_block *nb);
+
+extern int vfio_unregister_notifier(struct device *dev,
+ struct notifier_block *nb);
/*
* IRQfd - generic
*/
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 11/19] vfio: Introduce common function to add capabilities
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Vendor driver using mediated device framework should use
vfio_info_add_capability() to add capabilities.
Introduced this function to reduce code duplication in vendor drivers.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I6fca329fa2291f37a2c859d0bc97574d9e2ce1a6
---
drivers/vfio/vfio.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++-
include/linux/vfio.h | 3 +++
2 files changed, 63 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index ff05ac6b1e90..54d3dd71b783 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1797,7 +1797,66 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next - offset)
tmp->next += offset;
}
-EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
+EXPORT_SYMBOL(vfio_info_cap_shift);
+
+static int sparse_mmap_cap(struct vfio_info_cap *caps, void *cap_type)
+{
+ struct vfio_info_cap_header *header;
+ struct vfio_region_info_cap_sparse_mmap *sparse_cap, *sparse = cap_type;
+ size_t size;
+
+ size = sizeof(*sparse) + sparse->nr_areas * sizeof(*sparse->areas);
+ header = vfio_info_cap_add(caps, size,
+ VFIO_REGION_INFO_CAP_SPARSE_MMAP, 1);
+ if (IS_ERR(header))
+ return PTR_ERR(header);
+
+ sparse_cap = container_of(header,
+ struct vfio_region_info_cap_sparse_mmap, header);
+ sparse_cap->nr_areas = sparse->nr_areas;
+ memcpy(sparse_cap->areas, sparse->areas,
+ sparse->nr_areas * sizeof(*sparse->areas));
+ return 0;
+}
+
+static int region_type_cap(struct vfio_info_cap *caps, void *cap_type)
+{
+ struct vfio_info_cap_header *header;
+ struct vfio_region_info_cap_type *type_cap, *cap = cap_type;
+
+ header = vfio_info_cap_add(caps, sizeof(*cap),
+ VFIO_REGION_INFO_CAP_TYPE, 1);
+ if (IS_ERR(header))
+ return PTR_ERR(header);
+
+ type_cap = container_of(header, struct vfio_region_info_cap_type,
+ header);
+ type_cap->type = cap->type;
+ type_cap->subtype = cap->subtype;
+ return 0;
+}
+
+int vfio_info_add_capability(struct vfio_info_cap *caps, int cap_type_id,
+ void *cap_type)
+{
+ int ret = -EINVAL;
+
+ if (!cap_type)
+ return 0;
+
+ switch (cap_type_id) {
+ case VFIO_REGION_INFO_CAP_SPARSE_MMAP:
+ ret = sparse_mmap_cap(caps, cap_type);
+ break;
+
+ case VFIO_REGION_INFO_CAP_TYPE:
+ ret = region_type_cap(caps, cap_type);
+ break;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(vfio_info_add_capability);
/*
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 4c91ce8bfaeb..8e2141d4601b 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -111,6 +111,9 @@ extern struct vfio_info_cap_header *vfio_info_cap_add(
struct vfio_info_cap *caps, size_t size, u16 id, u16 version);
extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
+extern int vfio_info_add_capability(struct vfio_info_cap *caps,
+ int cap_type_id, void *cap_type);
+
struct pci_dev;
#ifdef CONFIG_EEH
extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 11/19] vfio: Introduce common function to add capabilities
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Vendor driver using mediated device framework should use
vfio_info_add_capability() to add capabilities.
Introduced this function to reduce code duplication in vendor drivers.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I6fca329fa2291f37a2c859d0bc97574d9e2ce1a6
---
drivers/vfio/vfio.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++-
include/linux/vfio.h | 3 +++
2 files changed, 63 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index ff05ac6b1e90..54d3dd71b783 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1797,7 +1797,66 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next - offset)
tmp->next += offset;
}
-EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
+EXPORT_SYMBOL(vfio_info_cap_shift);
+
+static int sparse_mmap_cap(struct vfio_info_cap *caps, void *cap_type)
+{
+ struct vfio_info_cap_header *header;
+ struct vfio_region_info_cap_sparse_mmap *sparse_cap, *sparse = cap_type;
+ size_t size;
+
+ size = sizeof(*sparse) + sparse->nr_areas * sizeof(*sparse->areas);
+ header = vfio_info_cap_add(caps, size,
+ VFIO_REGION_INFO_CAP_SPARSE_MMAP, 1);
+ if (IS_ERR(header))
+ return PTR_ERR(header);
+
+ sparse_cap = container_of(header,
+ struct vfio_region_info_cap_sparse_mmap, header);
+ sparse_cap->nr_areas = sparse->nr_areas;
+ memcpy(sparse_cap->areas, sparse->areas,
+ sparse->nr_areas * sizeof(*sparse->areas));
+ return 0;
+}
+
+static int region_type_cap(struct vfio_info_cap *caps, void *cap_type)
+{
+ struct vfio_info_cap_header *header;
+ struct vfio_region_info_cap_type *type_cap, *cap = cap_type;
+
+ header = vfio_info_cap_add(caps, sizeof(*cap),
+ VFIO_REGION_INFO_CAP_TYPE, 1);
+ if (IS_ERR(header))
+ return PTR_ERR(header);
+
+ type_cap = container_of(header, struct vfio_region_info_cap_type,
+ header);
+ type_cap->type = cap->type;
+ type_cap->subtype = cap->subtype;
+ return 0;
+}
+
+int vfio_info_add_capability(struct vfio_info_cap *caps, int cap_type_id,
+ void *cap_type)
+{
+ int ret = -EINVAL;
+
+ if (!cap_type)
+ return 0;
+
+ switch (cap_type_id) {
+ case VFIO_REGION_INFO_CAP_SPARSE_MMAP:
+ ret = sparse_mmap_cap(caps, cap_type);
+ break;
+
+ case VFIO_REGION_INFO_CAP_TYPE:
+ ret = region_type_cap(caps, cap_type);
+ break;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(vfio_info_add_capability);
/*
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 4c91ce8bfaeb..8e2141d4601b 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -111,6 +111,9 @@ extern struct vfio_info_cap_header *vfio_info_cap_add(
struct vfio_info_cap *caps, size_t size, u16 id, u16 version);
extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
+extern int vfio_info_add_capability(struct vfio_info_cap *caps,
+ int cap_type_id, void *cap_type);
+
struct pci_dev;
#ifdef CONFIG_EEH
extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 12/19] vfio_pci: Update vfio_pci to use vfio_info_add_capability()
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Update msix_sparse_mmap_cap() to use vfio_info_add_capability()
Update region type capability to use vfio_info_add_capability()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I52bb28c7875a6da5a79ddad1843e6088aff58a45
---
drivers/vfio/pci/vfio_pci.c | 49 ++++++++++++++++++---------------------------
1 file changed, 19 insertions(+), 30 deletions(-)
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index d624a527777f..16d8710ef9db 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -558,10 +558,9 @@ static int vfio_pci_for_each_slot_or_bus(struct pci_dev *pdev,
static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
struct vfio_info_cap *caps)
{
- struct vfio_info_cap_header *header;
struct vfio_region_info_cap_sparse_mmap *sparse;
size_t end, size;
- int nr_areas = 2, i = 0;
+ int nr_areas = 2, i = 0, ret;
end = pci_resource_len(vdev->pdev, vdev->msix_bar);
@@ -572,13 +571,10 @@ static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
size = sizeof(*sparse) + (nr_areas * sizeof(*sparse->areas));
- header = vfio_info_cap_add(caps, size,
- VFIO_REGION_INFO_CAP_SPARSE_MMAP, 1);
- if (IS_ERR(header))
- return PTR_ERR(header);
+ sparse = kzalloc(size, GFP_KERNEL);
+ if (!sparse)
+ return -ENOMEM;
- sparse = container_of(header,
- struct vfio_region_info_cap_sparse_mmap, header);
sparse->nr_areas = nr_areas;
if (vdev->msix_offset & PAGE_MASK) {
@@ -594,26 +590,11 @@ static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
i++;
}
- return 0;
-}
-
-static int region_type_cap(struct vfio_pci_device *vdev,
- struct vfio_info_cap *caps,
- unsigned int type, unsigned int subtype)
-{
- struct vfio_info_cap_header *header;
- struct vfio_region_info_cap_type *cap;
-
- header = vfio_info_cap_add(caps, sizeof(*cap),
- VFIO_REGION_INFO_CAP_TYPE, 1);
- if (IS_ERR(header))
- return PTR_ERR(header);
-
- cap = container_of(header, struct vfio_region_info_cap_type, header);
- cap->type = type;
- cap->subtype = subtype;
+ ret = vfio_info_add_capability(caps, VFIO_REGION_INFO_CAP_SPARSE_MMAP,
+ sparse);
+ kfree(sparse);
- return 0;
+ return ret;
}
int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
@@ -752,6 +733,9 @@ static long vfio_pci_ioctl(void *device_data,
break;
default:
+ {
+ struct vfio_region_info_cap_type cap_type;
+
if (info.index >=
VFIO_PCI_NUM_REGIONS + vdev->num_regions)
return -EINVAL;
@@ -762,11 +746,16 @@ static long vfio_pci_ioctl(void *device_data,
info.size = vdev->region[i].size;
info.flags = vdev->region[i].flags;
- ret = region_type_cap(vdev, &caps,
- vdev->region[i].type,
- vdev->region[i].subtype);
+ cap_type.type = vdev->region[i].type;
+ cap_type.subtype = vdev->region[i].subtype;
+
+ ret = vfio_info_add_capability(&caps,
+ VFIO_REGION_INFO_CAP_TYPE,
+ &cap_type);
if (ret)
return ret;
+
+ }
}
if (caps.size) {
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 12/19] vfio_pci: Update vfio_pci to use vfio_info_add_capability()
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Update msix_sparse_mmap_cap() to use vfio_info_add_capability()
Update region type capability to use vfio_info_add_capability()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I52bb28c7875a6da5a79ddad1843e6088aff58a45
---
drivers/vfio/pci/vfio_pci.c | 49 ++++++++++++++++++---------------------------
1 file changed, 19 insertions(+), 30 deletions(-)
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index d624a527777f..16d8710ef9db 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -558,10 +558,9 @@ static int vfio_pci_for_each_slot_or_bus(struct pci_dev *pdev,
static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
struct vfio_info_cap *caps)
{
- struct vfio_info_cap_header *header;
struct vfio_region_info_cap_sparse_mmap *sparse;
size_t end, size;
- int nr_areas = 2, i = 0;
+ int nr_areas = 2, i = 0, ret;
end = pci_resource_len(vdev->pdev, vdev->msix_bar);
@@ -572,13 +571,10 @@ static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
size = sizeof(*sparse) + (nr_areas * sizeof(*sparse->areas));
- header = vfio_info_cap_add(caps, size,
- VFIO_REGION_INFO_CAP_SPARSE_MMAP, 1);
- if (IS_ERR(header))
- return PTR_ERR(header);
+ sparse = kzalloc(size, GFP_KERNEL);
+ if (!sparse)
+ return -ENOMEM;
- sparse = container_of(header,
- struct vfio_region_info_cap_sparse_mmap, header);
sparse->nr_areas = nr_areas;
if (vdev->msix_offset & PAGE_MASK) {
@@ -594,26 +590,11 @@ static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
i++;
}
- return 0;
-}
-
-static int region_type_cap(struct vfio_pci_device *vdev,
- struct vfio_info_cap *caps,
- unsigned int type, unsigned int subtype)
-{
- struct vfio_info_cap_header *header;
- struct vfio_region_info_cap_type *cap;
-
- header = vfio_info_cap_add(caps, sizeof(*cap),
- VFIO_REGION_INFO_CAP_TYPE, 1);
- if (IS_ERR(header))
- return PTR_ERR(header);
-
- cap = container_of(header, struct vfio_region_info_cap_type, header);
- cap->type = type;
- cap->subtype = subtype;
+ ret = vfio_info_add_capability(caps, VFIO_REGION_INFO_CAP_SPARSE_MMAP,
+ sparse);
+ kfree(sparse);
- return 0;
+ return ret;
}
int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
@@ -752,6 +733,9 @@ static long vfio_pci_ioctl(void *device_data,
break;
default:
+ {
+ struct vfio_region_info_cap_type cap_type;
+
if (info.index >=
VFIO_PCI_NUM_REGIONS + vdev->num_regions)
return -EINVAL;
@@ -762,11 +746,16 @@ static long vfio_pci_ioctl(void *device_data,
info.size = vdev->region[i].size;
info.flags = vdev->region[i].flags;
- ret = region_type_cap(vdev, &caps,
- vdev->region[i].type,
- vdev->region[i].subtype);
+ cap_type.type = vdev->region[i].type;
+ cap_type.subtype = vdev->region[i].subtype;
+
+ ret = vfio_info_add_capability(&caps,
+ VFIO_REGION_INFO_CAP_TYPE,
+ &cap_type);
if (ret)
return ret;
+
+ }
}
if (caps.size) {
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 13/19] vfio: Introduce vfio_set_irqs_validate_and_prepare()
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Vendor driver using mediated device framework would use same mechnism to
validate and prepare IRQs. Introducing this function to reduce code
replication in multiple drivers.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Ie201f269dda0713ca18a07dc4852500bd8b48309
---
drivers/vfio/vfio.c | 39 +++++++++++++++++++++++++++++++++++++++
include/linux/vfio.h | 4 ++++
2 files changed, 43 insertions(+)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 54d3dd71b783..9fd278155640 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1858,6 +1858,45 @@ int vfio_info_add_capability(struct vfio_info_cap *caps, int cap_type_id,
}
EXPORT_SYMBOL(vfio_info_add_capability);
+int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, int num_irqs,
+ int max_irq_type, size_t *data_size)
+{
+ unsigned long minsz;
+
+ minsz = offsetofend(struct vfio_irq_set, count);
+
+ if ((hdr->argsz < minsz) || (hdr->index >= max_irq_type) ||
+ (hdr->flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
+ VFIO_IRQ_SET_ACTION_TYPE_MASK)))
+ return -EINVAL;
+
+ if (data_size)
+ *data_size = 0;
+
+ if (!(hdr->flags & VFIO_IRQ_SET_DATA_NONE)) {
+ size_t size;
+
+ if (hdr->flags & VFIO_IRQ_SET_DATA_BOOL)
+ size = sizeof(uint8_t);
+ else if (hdr->flags & VFIO_IRQ_SET_DATA_EVENTFD)
+ size = sizeof(int32_t);
+ else
+ return -EINVAL;
+
+ if ((hdr->argsz - minsz < hdr->count * size) ||
+ (hdr->start >= num_irqs) ||
+ (hdr->start + hdr->count > num_irqs))
+ return -EINVAL;
+
+ if (!data_size)
+ return -EINVAL;
+
+ *data_size = hdr->count * size;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
/*
* Pin a set of guest PFNs and return their associated host PFNs for local
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 8e2141d4601b..034c396c1706 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -114,6 +114,10 @@ extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
extern int vfio_info_add_capability(struct vfio_info_cap *caps,
int cap_type_id, void *cap_type);
+extern int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
+ int num_irqs, int max_irq_type,
+ size_t *data_size);
+
struct pci_dev;
#ifdef CONFIG_EEH
extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 13/19] vfio: Introduce vfio_set_irqs_validate_and_prepare()
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Vendor driver using mediated device framework would use same mechnism to
validate and prepare IRQs. Introducing this function to reduce code
replication in multiple drivers.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Ie201f269dda0713ca18a07dc4852500bd8b48309
---
drivers/vfio/vfio.c | 39 +++++++++++++++++++++++++++++++++++++++
include/linux/vfio.h | 4 ++++
2 files changed, 43 insertions(+)
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 54d3dd71b783..9fd278155640 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -1858,6 +1858,45 @@ int vfio_info_add_capability(struct vfio_info_cap *caps, int cap_type_id,
}
EXPORT_SYMBOL(vfio_info_add_capability);
+int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, int num_irqs,
+ int max_irq_type, size_t *data_size)
+{
+ unsigned long minsz;
+
+ minsz = offsetofend(struct vfio_irq_set, count);
+
+ if ((hdr->argsz < minsz) || (hdr->index >= max_irq_type) ||
+ (hdr->flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
+ VFIO_IRQ_SET_ACTION_TYPE_MASK)))
+ return -EINVAL;
+
+ if (data_size)
+ *data_size = 0;
+
+ if (!(hdr->flags & VFIO_IRQ_SET_DATA_NONE)) {
+ size_t size;
+
+ if (hdr->flags & VFIO_IRQ_SET_DATA_BOOL)
+ size = sizeof(uint8_t);
+ else if (hdr->flags & VFIO_IRQ_SET_DATA_EVENTFD)
+ size = sizeof(int32_t);
+ else
+ return -EINVAL;
+
+ if ((hdr->argsz - minsz < hdr->count * size) ||
+ (hdr->start >= num_irqs) ||
+ (hdr->start + hdr->count > num_irqs))
+ return -EINVAL;
+
+ if (!data_size)
+ return -EINVAL;
+
+ *data_size = hdr->count * size;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
/*
* Pin a set of guest PFNs and return their associated host PFNs for local
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 8e2141d4601b..034c396c1706 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -114,6 +114,10 @@ extern void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
extern int vfio_info_add_capability(struct vfio_info_cap *caps,
int cap_type_id, void *cap_type);
+extern int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
+ int num_irqs, int max_irq_type,
+ size_t *data_size);
+
struct pci_dev;
#ifdef CONFIG_EEH
extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 14/19] vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Updated vfio_pci.c file to use vfio_set_irqs_validate_and_prepare()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I9f3daba89d8dba5cb5b01a8cff420412f30686c7
---
drivers/vfio/pci/vfio_pci.c | 29 +++++++++--------------------
1 file changed, 9 insertions(+), 20 deletions(-)
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 16d8710ef9db..dcd7c2a99618 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -819,35 +819,24 @@ static long vfio_pci_ioctl(void *device_data,
} else if (cmd == VFIO_DEVICE_SET_IRQS) {
struct vfio_irq_set hdr;
u8 *data = NULL;
- int ret = 0;
+ int max, ret = 0;
+ size_t data_size = 0;
minsz = offsetofend(struct vfio_irq_set, count);
if (copy_from_user(&hdr, (void __user *)arg, minsz))
return -EFAULT;
- if (hdr.argsz < minsz || hdr.index >= VFIO_PCI_NUM_IRQS ||
- hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
- VFIO_IRQ_SET_ACTION_TYPE_MASK))
- return -EINVAL;
+ max = vfio_pci_get_irq_count(vdev, hdr.index);
- if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
- size_t size;
- int max = vfio_pci_get_irq_count(vdev, hdr.index);
-
- if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL)
- size = sizeof(uint8_t);
- else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD)
- size = sizeof(int32_t);
- else
- return -EINVAL;
-
- if (hdr.argsz - minsz < hdr.count * size ||
- hdr.start >= max || hdr.start + hdr.count > max)
- return -EINVAL;
+ ret = vfio_set_irqs_validate_and_prepare(&hdr, max,
+ VFIO_PCI_NUM_IRQS, &data_size);
+ if (ret)
+ return ret;
+ if (data_size) {
data = memdup_user((void __user *)(arg + minsz),
- hdr.count * size);
+ data_size);
if (IS_ERR(data))
return PTR_ERR(data);
}
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 14/19] vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Updated vfio_pci.c file to use vfio_set_irqs_validate_and_prepare()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I9f3daba89d8dba5cb5b01a8cff420412f30686c7
---
drivers/vfio/pci/vfio_pci.c | 29 +++++++++--------------------
1 file changed, 9 insertions(+), 20 deletions(-)
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 16d8710ef9db..dcd7c2a99618 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -819,35 +819,24 @@ static long vfio_pci_ioctl(void *device_data,
} else if (cmd == VFIO_DEVICE_SET_IRQS) {
struct vfio_irq_set hdr;
u8 *data = NULL;
- int ret = 0;
+ int max, ret = 0;
+ size_t data_size = 0;
minsz = offsetofend(struct vfio_irq_set, count);
if (copy_from_user(&hdr, (void __user *)arg, minsz))
return -EFAULT;
- if (hdr.argsz < minsz || hdr.index >= VFIO_PCI_NUM_IRQS ||
- hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
- VFIO_IRQ_SET_ACTION_TYPE_MASK))
- return -EINVAL;
+ max = vfio_pci_get_irq_count(vdev, hdr.index);
- if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
- size_t size;
- int max = vfio_pci_get_irq_count(vdev, hdr.index);
-
- if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL)
- size = sizeof(uint8_t);
- else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD)
- size = sizeof(int32_t);
- else
- return -EINVAL;
-
- if (hdr.argsz - minsz < hdr.count * size ||
- hdr.start >= max || hdr.start + hdr.count > max)
- return -EINVAL;
+ ret = vfio_set_irqs_validate_and_prepare(&hdr, max,
+ VFIO_PCI_NUM_IRQS, &data_size);
+ if (ret)
+ return ret;
+ if (data_size) {
data = memdup_user((void __user *)(arg + minsz),
- hdr.count * size);
+ data_size);
if (IS_ERR(data))
return PTR_ERR(data);
}
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 15/19] vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Updated vfio_platform_common.c file to use
vfio_set_irqs_validate_and_prepare()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Id87cd6b78ae901610b39bf957974baa6f40cd7b0
---
drivers/vfio/platform/vfio_platform_common.c | 31 +++++++---------------------
1 file changed, 8 insertions(+), 23 deletions(-)
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index d78142830754..4c27f4be3c3d 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -364,36 +364,21 @@ static long vfio_platform_ioctl(void *device_data,
struct vfio_irq_set hdr;
u8 *data = NULL;
int ret = 0;
+ size_t data_size = 0;
minsz = offsetofend(struct vfio_irq_set, count);
if (copy_from_user(&hdr, (void __user *)arg, minsz))
return -EFAULT;
- if (hdr.argsz < minsz)
- return -EINVAL;
-
- if (hdr.index >= vdev->num_irqs)
- return -EINVAL;
-
- if (hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
- VFIO_IRQ_SET_ACTION_TYPE_MASK))
- return -EINVAL;
-
- if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
- size_t size;
-
- if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL)
- size = sizeof(uint8_t);
- else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD)
- size = sizeof(int32_t);
- else
- return -EINVAL;
-
- if (hdr.argsz - minsz < size)
- return -EINVAL;
+ ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
+ vdev->num_irqs, &data_size);
+ if (ret)
+ return ret;
- data = memdup_user((void __user *)(arg + minsz), size);
+ if (data_size) {
+ data = memdup_user((void __user *)(arg + minsz),
+ data_size);
if (IS_ERR(data))
return PTR_ERR(data);
}
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 15/19] vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Updated vfio_platform_common.c file to use
vfio_set_irqs_validate_and_prepare()
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Id87cd6b78ae901610b39bf957974baa6f40cd7b0
---
drivers/vfio/platform/vfio_platform_common.c | 31 +++++++---------------------
1 file changed, 8 insertions(+), 23 deletions(-)
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index d78142830754..4c27f4be3c3d 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -364,36 +364,21 @@ static long vfio_platform_ioctl(void *device_data,
struct vfio_irq_set hdr;
u8 *data = NULL;
int ret = 0;
+ size_t data_size = 0;
minsz = offsetofend(struct vfio_irq_set, count);
if (copy_from_user(&hdr, (void __user *)arg, minsz))
return -EFAULT;
- if (hdr.argsz < minsz)
- return -EINVAL;
-
- if (hdr.index >= vdev->num_irqs)
- return -EINVAL;
-
- if (hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
- VFIO_IRQ_SET_ACTION_TYPE_MASK))
- return -EINVAL;
-
- if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
- size_t size;
-
- if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL)
- size = sizeof(uint8_t);
- else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD)
- size = sizeof(int32_t);
- else
- return -EINVAL;
-
- if (hdr.argsz - minsz < size)
- return -EINVAL;
+ ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
+ vdev->num_irqs, &data_size);
+ if (ret)
+ return ret;
- data = memdup_user((void __user *)(arg + minsz), size);
+ if (data_size) {
+ data = memdup_user((void __user *)(arg + minsz),
+ data_size);
if (IS_ERR(data))
return PTR_ERR(data);
}
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 16/19] vfio: Define device_api strings
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Defined device API strings. Vendor driver using mediated device
framework should use corresponding string for device_api attribute.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I42d29f475f02a7132ce13297fbf2b48f1da10995
---
include/uapi/linux/vfio.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 255a2113f53c..519eff362c1c 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -203,6 +203,16 @@ struct vfio_device_info {
};
#define VFIO_DEVICE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 7)
+/*
+ * Vendor driver using Mediated device framework should provide device_api
+ * attribute in supported type attribute groups. Device API string should be one
+ * of the following corresponding to device flags in vfio_device_info structure.
+ */
+
+#define VFIO_DEVICE_API_PCI_STRING "vfio-pci"
+#define VFIO_DEVICE_API_PLATFORM_STRING "vfio-platform"
+#define VFIO_DEVICE_API_AMBA_STRING "vfio-amba"
+
/**
* VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 8,
* struct vfio_region_info)
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 16/19] vfio: Define device_api strings
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Defined device API strings. Vendor driver using mediated device
framework should use corresponding string for device_api attribute.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I42d29f475f02a7132ce13297fbf2b48f1da10995
---
include/uapi/linux/vfio.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 255a2113f53c..519eff362c1c 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -203,6 +203,16 @@ struct vfio_device_info {
};
#define VFIO_DEVICE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 7)
+/*
+ * Vendor driver using Mediated device framework should provide device_api
+ * attribute in supported type attribute groups. Device API string should be one
+ * of the following corresponding to device flags in vfio_device_info structure.
+ */
+
+#define VFIO_DEVICE_API_PCI_STRING "vfio-pci"
+#define VFIO_DEVICE_API_PLATFORM_STRING "vfio-platform"
+#define VFIO_DEVICE_API_AMBA_STRING "vfio-amba"
+
/**
* VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 8,
* struct vfio_region_info)
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 17/19] docs: Add Documentation for Mediated devices
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Add file Documentation/vfio-mediated-device.txt that include details of
mediated device framework.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I137dd646442936090d92008b115908b7b2c7bc5d
---
Documentation/vfio-mdev/vfio-mediated-device.txt | 297 +++++++++++++++++++++++
1 file changed, 297 insertions(+)
create mode 100644 Documentation/vfio-mdev/vfio-mediated-device.txt
diff --git a/Documentation/vfio-mdev/vfio-mediated-device.txt b/Documentation/vfio-mdev/vfio-mediated-device.txt
new file mode 100644
index 000000000000..69660aff86e3
--- /dev/null
+++ b/Documentation/vfio-mdev/vfio-mediated-device.txt
@@ -0,0 +1,297 @@
+/*
+ * VFIO Mediated devices
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+Virtual Function I/O (VFIO) Mediated devices[1]
+===============================================
+
+The number of use cases for virtualizing DMA devices that do not have built-in
+SR_IOV capability is increasing. Previously, to virtualize such devices,
+developers had to create their own management interfaces and APIs, and then
+integrate them with user space software. To simplify integration with user space
+software, we have identified common requirements and a unified management
+interface for such devices.
+
+The VFIO driver framework provides unified APIs for direct device access. It is
+an IOMMU/device-agnostic framework for exposing direct device access to user
+space in a secure, IOMMU-protected environment. This framework is used for
+multiple devices, such as GPUs, network adapters, and compute accelerators. With
+direct device access, virtual machines or user space applications have direct
+access to the physical device. This framework is reused for mediated devices.
+
+The mediated core driver provides a common interface for mediated device
+management that can be used by drivers of different devices. This module
+provides a generic interface to perform these operations:
+
+* Create and destroy a mediated device
+* Add a mediated device to and remove it from a mediated bus driver
+* Add a mediated device to and remove it from an IOMMU group
+
+The mediated core driver also provides an interface to register a bus driver.
+For example, the mediated VFIO mdev driver is designed for mediated devices and
+supports VFIO APIs. The mediated bus driver adds a mediated device to and
+removes it from a VFIO group.
+
+The following high-level block diagram shows the main components and interfaces
+in the VFIO mediated driver framework. The diagram shows NVIDIA, Intel, and IBM
+devices as examples, as these devices are the first devices to use this module.
+
+ +---------------+
+ | |
+ | +-----------+ | mdev_register_driver() +--------------+
+ | | | +<------------------------+ |
+ | | mdev | | | |
+ | | bus | +------------------------>+ vfio_mdev.ko |<-> VFIO user
+ | | driver | | probe()/remove() | | APIs
+ | | | | +--------------+
+ | +-----------+ |
+ | |
+ | MDEV CORE |
+ | MODULE |
+ | mdev.ko |
+ | +-----------+ | mdev_register_device() +--------------+
+ | | | +<------------------------+ |
+ | | | | | nvidia.ko |<-> physical
+ | | | +------------------------>+ | device
+ | | | | callbacks +--------------+
+ | | Physical | |
+ | | device | | mdev_register_device() +--------------+
+ | | interface | |<------------------------+ |
+ | | | | | i915.ko |<-> physical
+ | | | +------------------------>+ | device
+ | | | | callbacks +--------------+
+ | | | |
+ | | | | mdev_register_device() +--------------+
+ | | | +<------------------------+ |
+ | | | | | ccw_device.ko|<-> physical
+ | | | +------------------------>+ | device
+ | | | | callbacks +--------------+
+ | +-----------+ |
+ +---------------+
+
+
+Registration Interfaces
+=======================
+
+The mediated core driver provides the following types of registration
+interfaces:
+
+* Registration interface for a mediated bus driver
+* Physical device driver interface
+
+Registration Interface for a Mediated Bus Driver
+------------------------------------------------
+
+The registration interface for a mediated bus driver provides the following
+structure to represent a mediated device's driver:
+
+ /*
+ * struct mdev_driver [2] - Mediated device's driver
+ * @name: driver name
+ * @probe: called when new device created
+ * @remove: called when device removed
+ * @driver: device driver structure
+ */
+ struct mdev_driver {
+ const char *name;
+ int (*probe) (struct device *dev);
+ void (*remove) (struct device *dev);
+ struct device_driver driver;
+ };
+
+A mediated bus driver for mdev should use this structure in the function calls
+to register and unregister itself with the core driver:
+
+* Register:
+
+ extern int mdev_register_driver(struct mdev_driver *drv,
+ struct module *owner);
+
+* Unregister:
+
+ extern void mdev_unregister_driver(struct mdev_driver *drv);
+
+The mediated bus driver is responsible for adding mediated devices to the VFIO
+group when devices are bound to the driver and removing mediated devices from
+the VFIO when devices are unbound from the driver.
+
+
+Physical Device Driver Interface
+--------------------------------
+
+The physical device driver interface provides the parent_ops[3] structure to
+define the APIs to manage work in the mediated core driver that is related to
+the physical device.
+
+The structures in the parent_ops structure are as follows:
+
+* dev_attr_groups: attributes of the parent device
+* mdev_attr_groups: attributes of the mediated device
+* supported_config: attributes to define supported configurations
+
+The functions in the parent_ops structure are as follows:
+
+* create: allocate basic resources in a driver for a mediated device
+* remove: free resources in a driver when a mediated device is destroyed
+
+The callbacks in the parent_ops structure are as follows:
+
+* open: open callback of mediated device
+* close: close callback of mediated device
+* ioctl: ioctl callback of mediated device
+* read : read emulation callback
+* write: write emulation callback
+* mmap: mmap emulation callback
+
+A driver should use the parent_ops structure in the function call to register
+itself with the mdev core driver:
+
+extern int mdev_register_device(struct device *dev,
+ const struct parent_ops *ops);
+
+However, the parent_ops structure is not required in the function call that a
+driver should use to unregister itself with the mdev core driver:
+
+extern void mdev_unregister_device(struct device *dev);
+
+
+Mediated Device Management Interface Through sysfs
+==================================================
+
+The management interface through sysfs enables user space software, such as
+libvirt, to query and configure mediated devices in a hardware-agnostic fashion.
+This management interface provides flexibility to the underlying physical
+device's driver to support features such as:
+
+* Mediated device hot plug
+* Multiple mediated devices in a single virtual machine
+* Multiple mediated devices from different physical devices
+
+Links in the mdev_bus Class Directory
+-------------------------------------
+The /sys/class/mdev_bus/ directory contains links to devices that are registered
+with the mdev core driver.
+
+Directories and files under the sysfs for Each Physical Device
+--------------------------------------------------------------
+
+|- [parent physical device]
+|--- Vendor-specific-attributes [optional]
+|--- [mdev_supported_types]
+| |--- [<type-id>]
+| | |--- create
+| | |--- name
+| | |--- available_instances
+| | |--- device_api
+| | |--- description
+| | |--- [devices]
+| |--- [<type-id>]
+| | |--- create
+| | |--- name
+| | |--- available_instances
+| | |--- device_api
+| | |--- description
+| | |--- [devices]
+| |--- [<type-id>]
+| |--- create
+| |--- name
+| |--- available_instances
+| |--- device_api
+| |--- description
+| |--- [devices]
+
+* [mdev_supported_types]
+
+ The list of currently supported mediated device types and their details.
+
+ [<type-id>], device_api, and available_instances are mandatory attributes
+ that should be provided by vendor driver.
+
+* [<type-id>]
+
+ The [<type-id>] name is created by adding the the device driver string as a
+ prefix to the string provided by the vendor driver. This format of this name
+ is as follows:
+
+ sprintf(buf, "%s-%s", dev_driver_string(parent->dev), group->name);
+
+* device_api
+
+ This attribute should show which device API is being created, for example,
+ "vfio-pci" for a PCI device.
+
+* available_instances
+
+ This attribute should show the number of devices of type <type-id> that can be
+ created.
+
+* [device]
+
+ This directory contains links to the devices of type <type-id> that have been
+created.
+
+* name
+
+ This attribute should show human readable name. This is optional attribute.
+
+* description
+
+ This attribute should show brief features/description of the type. This is
+ optional attribute.
+
+Directories and Files Under the sysfs for Each mdev Device
+----------------------------------------------------------
+
+|- [parent phy device]
+|--- [$MDEV_UUID]
+ |--- remove
+ |--- mdev_type {link to its type}
+ |--- vendor-specific-attributes [optional]
+
+* remove (write only)
+Writing '1' to the 'remove' file destroys the mdev device. The vendor driver can
+fail the remove() callback if that device is active and the vendor driver
+doesn't support hot unplug.
+
+Example:
+ # echo 1 > /sys/bus/mdev/devices/$mdev_UUID/remove
+
+Mediated device Hot plug:
+------------------------
+
+Mediated devices can be created and assigned at runtime. The procedure to hot
+plug a mediated device is the same as the procedure to hot plug a PCI device.
+
+Translation APIs for Mediated Devices
+=====================================
+
+The following APIs are provided for translating user pfn to host pfn in a VFIO
+driver:
+
+ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+ long npage, int prot, unsigned long *phys_pfn);
+
+ extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
+ long npage);
+
+These functions call back into the back-end IOMMU module by using the pin_pages
+and unpin_pages callbacks of the struct vfio_iommu_driver_ops[4]. Currently
+these callbacks are supported in the TYPE1 IOMMU module. To enable them for
+other IOMMU backend modules, such as PPC64 sPAPR module, they need to provide
+these two callback functions.
+
+References
+----------
+
+[1] See Documentation/vfio.txt for more information on VFIO.
+[2] struct mdev_driver in include/linux/mdev.h
+[3] struct parent_ops in include/linux/mdev.h
+[4] struct vfio_iommu_driver_ops in include/linux/vfio.h
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 17/19] docs: Add Documentation for Mediated devices
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Add file Documentation/vfio-mediated-device.txt that include details of
mediated device framework.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I137dd646442936090d92008b115908b7b2c7bc5d
---
Documentation/vfio-mdev/vfio-mediated-device.txt | 297 +++++++++++++++++++++++
1 file changed, 297 insertions(+)
create mode 100644 Documentation/vfio-mdev/vfio-mediated-device.txt
diff --git a/Documentation/vfio-mdev/vfio-mediated-device.txt b/Documentation/vfio-mdev/vfio-mediated-device.txt
new file mode 100644
index 000000000000..69660aff86e3
--- /dev/null
+++ b/Documentation/vfio-mdev/vfio-mediated-device.txt
@@ -0,0 +1,297 @@
+/*
+ * VFIO Mediated devices
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+Virtual Function I/O (VFIO) Mediated devices[1]
+===============================================
+
+The number of use cases for virtualizing DMA devices that do not have built-in
+SR_IOV capability is increasing. Previously, to virtualize such devices,
+developers had to create their own management interfaces and APIs, and then
+integrate them with user space software. To simplify integration with user space
+software, we have identified common requirements and a unified management
+interface for such devices.
+
+The VFIO driver framework provides unified APIs for direct device access. It is
+an IOMMU/device-agnostic framework for exposing direct device access to user
+space in a secure, IOMMU-protected environment. This framework is used for
+multiple devices, such as GPUs, network adapters, and compute accelerators. With
+direct device access, virtual machines or user space applications have direct
+access to the physical device. This framework is reused for mediated devices.
+
+The mediated core driver provides a common interface for mediated device
+management that can be used by drivers of different devices. This module
+provides a generic interface to perform these operations:
+
+* Create and destroy a mediated device
+* Add a mediated device to and remove it from a mediated bus driver
+* Add a mediated device to and remove it from an IOMMU group
+
+The mediated core driver also provides an interface to register a bus driver.
+For example, the mediated VFIO mdev driver is designed for mediated devices and
+supports VFIO APIs. The mediated bus driver adds a mediated device to and
+removes it from a VFIO group.
+
+The following high-level block diagram shows the main components and interfaces
+in the VFIO mediated driver framework. The diagram shows NVIDIA, Intel, and IBM
+devices as examples, as these devices are the first devices to use this module.
+
+ +---------------+
+ | |
+ | +-----------+ | mdev_register_driver() +--------------+
+ | | | +<------------------------+ |
+ | | mdev | | | |
+ | | bus | +------------------------>+ vfio_mdev.ko |<-> VFIO user
+ | | driver | | probe()/remove() | | APIs
+ | | | | +--------------+
+ | +-----------+ |
+ | |
+ | MDEV CORE |
+ | MODULE |
+ | mdev.ko |
+ | +-----------+ | mdev_register_device() +--------------+
+ | | | +<------------------------+ |
+ | | | | | nvidia.ko |<-> physical
+ | | | +------------------------>+ | device
+ | | | | callbacks +--------------+
+ | | Physical | |
+ | | device | | mdev_register_device() +--------------+
+ | | interface | |<------------------------+ |
+ | | | | | i915.ko |<-> physical
+ | | | +------------------------>+ | device
+ | | | | callbacks +--------------+
+ | | | |
+ | | | | mdev_register_device() +--------------+
+ | | | +<------------------------+ |
+ | | | | | ccw_device.ko|<-> physical
+ | | | +------------------------>+ | device
+ | | | | callbacks +--------------+
+ | +-----------+ |
+ +---------------+
+
+
+Registration Interfaces
+=======================
+
+The mediated core driver provides the following types of registration
+interfaces:
+
+* Registration interface for a mediated bus driver
+* Physical device driver interface
+
+Registration Interface for a Mediated Bus Driver
+------------------------------------------------
+
+The registration interface for a mediated bus driver provides the following
+structure to represent a mediated device's driver:
+
+ /*
+ * struct mdev_driver [2] - Mediated device's driver
+ * @name: driver name
+ * @probe: called when new device created
+ * @remove: called when device removed
+ * @driver: device driver structure
+ */
+ struct mdev_driver {
+ const char *name;
+ int (*probe) (struct device *dev);
+ void (*remove) (struct device *dev);
+ struct device_driver driver;
+ };
+
+A mediated bus driver for mdev should use this structure in the function calls
+to register and unregister itself with the core driver:
+
+* Register:
+
+ extern int mdev_register_driver(struct mdev_driver *drv,
+ struct module *owner);
+
+* Unregister:
+
+ extern void mdev_unregister_driver(struct mdev_driver *drv);
+
+The mediated bus driver is responsible for adding mediated devices to the VFIO
+group when devices are bound to the driver and removing mediated devices from
+the VFIO when devices are unbound from the driver.
+
+
+Physical Device Driver Interface
+--------------------------------
+
+The physical device driver interface provides the parent_ops[3] structure to
+define the APIs to manage work in the mediated core driver that is related to
+the physical device.
+
+The structures in the parent_ops structure are as follows:
+
+* dev_attr_groups: attributes of the parent device
+* mdev_attr_groups: attributes of the mediated device
+* supported_config: attributes to define supported configurations
+
+The functions in the parent_ops structure are as follows:
+
+* create: allocate basic resources in a driver for a mediated device
+* remove: free resources in a driver when a mediated device is destroyed
+
+The callbacks in the parent_ops structure are as follows:
+
+* open: open callback of mediated device
+* close: close callback of mediated device
+* ioctl: ioctl callback of mediated device
+* read : read emulation callback
+* write: write emulation callback
+* mmap: mmap emulation callback
+
+A driver should use the parent_ops structure in the function call to register
+itself with the mdev core driver:
+
+extern int mdev_register_device(struct device *dev,
+ const struct parent_ops *ops);
+
+However, the parent_ops structure is not required in the function call that a
+driver should use to unregister itself with the mdev core driver:
+
+extern void mdev_unregister_device(struct device *dev);
+
+
+Mediated Device Management Interface Through sysfs
+==================================================
+
+The management interface through sysfs enables user space software, such as
+libvirt, to query and configure mediated devices in a hardware-agnostic fashion.
+This management interface provides flexibility to the underlying physical
+device's driver to support features such as:
+
+* Mediated device hot plug
+* Multiple mediated devices in a single virtual machine
+* Multiple mediated devices from different physical devices
+
+Links in the mdev_bus Class Directory
+-------------------------------------
+The /sys/class/mdev_bus/ directory contains links to devices that are registered
+with the mdev core driver.
+
+Directories and files under the sysfs for Each Physical Device
+--------------------------------------------------------------
+
+|- [parent physical device]
+|--- Vendor-specific-attributes [optional]
+|--- [mdev_supported_types]
+| |--- [<type-id>]
+| | |--- create
+| | |--- name
+| | |--- available_instances
+| | |--- device_api
+| | |--- description
+| | |--- [devices]
+| |--- [<type-id>]
+| | |--- create
+| | |--- name
+| | |--- available_instances
+| | |--- device_api
+| | |--- description
+| | |--- [devices]
+| |--- [<type-id>]
+| |--- create
+| |--- name
+| |--- available_instances
+| |--- device_api
+| |--- description
+| |--- [devices]
+
+* [mdev_supported_types]
+
+ The list of currently supported mediated device types and their details.
+
+ [<type-id>], device_api, and available_instances are mandatory attributes
+ that should be provided by vendor driver.
+
+* [<type-id>]
+
+ The [<type-id>] name is created by adding the the device driver string as a
+ prefix to the string provided by the vendor driver. This format of this name
+ is as follows:
+
+ sprintf(buf, "%s-%s", dev_driver_string(parent->dev), group->name);
+
+* device_api
+
+ This attribute should show which device API is being created, for example,
+ "vfio-pci" for a PCI device.
+
+* available_instances
+
+ This attribute should show the number of devices of type <type-id> that can be
+ created.
+
+* [device]
+
+ This directory contains links to the devices of type <type-id> that have been
+created.
+
+* name
+
+ This attribute should show human readable name. This is optional attribute.
+
+* description
+
+ This attribute should show brief features/description of the type. This is
+ optional attribute.
+
+Directories and Files Under the sysfs for Each mdev Device
+----------------------------------------------------------
+
+|- [parent phy device]
+|--- [$MDEV_UUID]
+ |--- remove
+ |--- mdev_type {link to its type}
+ |--- vendor-specific-attributes [optional]
+
+* remove (write only)
+Writing '1' to the 'remove' file destroys the mdev device. The vendor driver can
+fail the remove() callback if that device is active and the vendor driver
+doesn't support hot unplug.
+
+Example:
+ # echo 1 > /sys/bus/mdev/devices/$mdev_UUID/remove
+
+Mediated device Hot plug:
+------------------------
+
+Mediated devices can be created and assigned at runtime. The procedure to hot
+plug a mediated device is the same as the procedure to hot plug a PCI device.
+
+Translation APIs for Mediated Devices
+=====================================
+
+The following APIs are provided for translating user pfn to host pfn in a VFIO
+driver:
+
+ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+ long npage, int prot, unsigned long *phys_pfn);
+
+ extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
+ long npage);
+
+These functions call back into the back-end IOMMU module by using the pin_pages
+and unpin_pages callbacks of the struct vfio_iommu_driver_ops[4]. Currently
+these callbacks are supported in the TYPE1 IOMMU module. To enable them for
+other IOMMU backend modules, such as PPC64 sPAPR module, they need to provide
+these two callback functions.
+
+References
+----------
+
+[1] See Documentation/vfio.txt for more information on VFIO.
+[2] struct mdev_driver in include/linux/mdev.h
+[3] struct parent_ops in include/linux/mdev.h
+[4] struct vfio_iommu_driver_ops in include/linux/vfio.h
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 18/19] docs: Sysfs ABI for mediated device framework
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Added details of sysfs ABI for mediated device framework
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Icb0fd4ed58a2fa793fbcb1c3d5009a4403c1f3ac
---
Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++++++++++++++++++++++++++
1 file changed, 111 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
diff --git a/Documentation/ABI/testing/sysfs-bus-vfio-mdev b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
new file mode 100644
index 000000000000..452dbe39270e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
@@ -0,0 +1,111 @@
+What: /sys/.../<device>/mdev_supported_types/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory contains list of directories of currently
+ supported mediated device types and their details for
+ <device>. Supported type attributes are defined by the
+ vendor driver who registers with Mediated device framework.
+ Each supported type is a directory whose name is created
+ by adding the device driver string as a prefix to the
+ string provided by the vendor driver.
+
+What: /sys/.../<device>/mdev_supported_types/<type-id>/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory gives details of supported type, like name,
+ description, available_instances, device_api etc.
+ 'device_api' and 'available_instances' are mandatory
+ attributes to be provided by vendor driver. 'name',
+ 'description' and other vendor driver specific attributes
+ are optional.
+
+What: /sys/.../mdev_supported_types/<type-id>/create
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Writing UUID to this file will create mediated device of
+ type <type-id> for parent device <device>. This is a
+ write-only file.
+ For example:
+ # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > \
+ /sys/devices/foo/mdev_supported_types/foo-1/create
+
+What: /sys/.../mdev_supported_types/<type-id>/devices/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory contains symbolic links pointing to mdev
+ devices sysfs entries which are created of this <type-id>.
+
+What: /sys/.../mdev_supported_types/<type-id>/available_instances
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show the number of mediated
+ devices of type <type-id> that can be created. This is a
+ readonly file.
+Users:
+ Userspace applications interested in creating mediated
+ device of that type. Userspace application should check
+ the number of available instances could be created before
+ creating mediated device of this type.
+
+What: /sys/.../mdev_supported_types/<type-id>/device_api
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show VFIO device API supported
+ by this type. For example, "vfio-pci" for a PCI device,
+ "vfio-platform" for platform device.
+
+What: /sys/.../mdev_supported_types/<type-id>/name
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show human readable name of the
+ mediated device that will get created of type <type-id>.
+ This is optional attribute. For example: "Grid M60-0Q"
+Users:
+ Userspace applications interested in knowing the name of
+ a particular <type-id> that can help in understanding the
+ type of mediated device.
+
+What: /sys/.../mdev_supported_types/<type-id>/description
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show description of the type of
+ mediated device that will get created of type <type-id>.
+ This is optional attribute. For example:
+ "2 heads, 512M FB, 2560x1600 maximum resolution"
+Users:
+ Userspace applications interested in knowing the details of
+ a particular <type-id> that can help in understanding the
+ features provided by that type of mediated device.
+
+What: /sys/.../<device>/<UUID>/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory represents device directory of mediated
+ device. It contains all the attributes related to mediated
+ device.
+
+What: /sys/.../<device>/<UUID>/mdev_type
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This is symbolic link pointing to supported type, <type-id>
+ directory of which this mediated device is created.
+
+What: /sys/.../<device>/<UUID>/remove
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Writing '1' to this file destroys the mediated device. The
+ vendor driver can fail the remove() callback if that device
+ is active and the vendor driver doesn't support hot unplug.
+ Example:
+ # echo 1 > /sys/bus/mdev/devices/<UUID>/remove
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 18/19] docs: Sysfs ABI for mediated device framework
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
Added details of sysfs ABI for mediated device framework
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: Icb0fd4ed58a2fa793fbcb1c3d5009a4403c1f3ac
---
Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++++++++++++++++++++++++++
1 file changed, 111 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
diff --git a/Documentation/ABI/testing/sysfs-bus-vfio-mdev b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
new file mode 100644
index 000000000000..452dbe39270e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
@@ -0,0 +1,111 @@
+What: /sys/.../<device>/mdev_supported_types/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory contains list of directories of currently
+ supported mediated device types and their details for
+ <device>. Supported type attributes are defined by the
+ vendor driver who registers with Mediated device framework.
+ Each supported type is a directory whose name is created
+ by adding the device driver string as a prefix to the
+ string provided by the vendor driver.
+
+What: /sys/.../<device>/mdev_supported_types/<type-id>/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory gives details of supported type, like name,
+ description, available_instances, device_api etc.
+ 'device_api' and 'available_instances' are mandatory
+ attributes to be provided by vendor driver. 'name',
+ 'description' and other vendor driver specific attributes
+ are optional.
+
+What: /sys/.../mdev_supported_types/<type-id>/create
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Writing UUID to this file will create mediated device of
+ type <type-id> for parent device <device>. This is a
+ write-only file.
+ For example:
+ # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > \
+ /sys/devices/foo/mdev_supported_types/foo-1/create
+
+What: /sys/.../mdev_supported_types/<type-id>/devices/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory contains symbolic links pointing to mdev
+ devices sysfs entries which are created of this <type-id>.
+
+What: /sys/.../mdev_supported_types/<type-id>/available_instances
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show the number of mediated
+ devices of type <type-id> that can be created. This is a
+ readonly file.
+Users:
+ Userspace applications interested in creating mediated
+ device of that type. Userspace application should check
+ the number of available instances could be created before
+ creating mediated device of this type.
+
+What: /sys/.../mdev_supported_types/<type-id>/device_api
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show VFIO device API supported
+ by this type. For example, "vfio-pci" for a PCI device,
+ "vfio-platform" for platform device.
+
+What: /sys/.../mdev_supported_types/<type-id>/name
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show human readable name of the
+ mediated device that will get created of type <type-id>.
+ This is optional attribute. For example: "Grid M60-0Q"
+Users:
+ Userspace applications interested in knowing the name of
+ a particular <type-id> that can help in understanding the
+ type of mediated device.
+
+What: /sys/.../mdev_supported_types/<type-id>/description
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Reading this attribute will show description of the type of
+ mediated device that will get created of type <type-id>.
+ This is optional attribute. For example:
+ "2 heads, 512M FB, 2560x1600 maximum resolution"
+Users:
+ Userspace applications interested in knowing the details of
+ a particular <type-id> that can help in understanding the
+ features provided by that type of mediated device.
+
+What: /sys/.../<device>/<UUID>/
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This directory represents device directory of mediated
+ device. It contains all the attributes related to mediated
+ device.
+
+What: /sys/.../<device>/<UUID>/mdev_type
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ This is symbolic link pointing to supported type, <type-id>
+ directory of which this mediated device is created.
+
+What: /sys/.../<device>/<UUID>/remove
+Date: October 2016
+Contact: Kirti Wankhede <kwankhede@nvidia.com>
+Description:
+ Writing '1' to this file destroys the mediated device. The
+ vendor driver can fail the remove() callback if that device
+ is active and the vendor driver doesn't support hot unplug.
+ Example:
+ # echo 1 > /sys/bus/mdev/devices/<UUID>/remove
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [PATCH v10 19/19] docs: Sample driver to demonstrate how to use Mediated device framework.
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-26 21:29 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
The Sample driver creates mdev device that simulates serial port over PCI
card.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I857f8f12f8b275f2498dfe8c628a5cdc7193b1b2
---
Documentation/vfio-mdev/Makefile | 13 +
Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
Documentation/vfio-mdev/vfio-mediated-device.txt | 103 +-
3 files changed, 1618 insertions(+), 1 deletion(-)
create mode 100644 Documentation/vfio-mdev/Makefile
create mode 100644 Documentation/vfio-mdev/mtty.c
diff --git a/Documentation/vfio-mdev/Makefile b/Documentation/vfio-mdev/Makefile
new file mode 100644
index 000000000000..a932edbe38eb
--- /dev/null
+++ b/Documentation/vfio-mdev/Makefile
@@ -0,0 +1,13 @@
+#
+# Makefile for mtty.c file
+#
+KERNEL_DIR:=/lib/modules/$(shell uname -r)/build
+
+obj-m:=mtty.o
+
+modules clean modules_install:
+ $(MAKE) -C $(KERNEL_DIR) SUBDIRS=$(PWD) $@
+
+default: modules
+
+module: modules
diff --git a/Documentation/vfio-mdev/mtty.c b/Documentation/vfio-mdev/mtty.c
new file mode 100644
index 000000000000..6c71d12288d1
--- /dev/null
+++ b/Documentation/vfio-mdev/mtty.c
@@ -0,0 +1,1503 @@
+/*
+ * Mediated virtual PCI serial host device driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Sample driver that creates mdev device that simulates serial port over PCI
+ * card.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/cdev.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/uuid.h>
+#include <linux/vfio.h>
+#include <linux/iommu.h>
+#include <linux/sysfs.h>
+#include <linux/ctype.h>
+#include <linux/file.h>
+#include <linux/mdev.h>
+#include <linux/pci.h>
+#include <linux/serial.h>
+#include <uapi/linux/serial_reg.h>
+#include <linux/eventfd.h>
+/*
+ * #defines
+ */
+
+#define VERSION_STRING "0.1"
+#define DRIVER_AUTHOR "NVIDIA Corporation"
+
+#define MTTY_CLASS_NAME "mtty"
+
+#define MTTY_NAME "mtty"
+
+#define MTTY_STRING_LEN 16
+
+#define MTTY_CONFIG_SPACE_SIZE 0xff
+#define MTTY_IO_BAR_SIZE 0x8
+#define MTTY_MMIO_BAR_SIZE 0x100000
+
+#define STORE_LE16(addr, val) (*(u16 *)addr = val)
+#define STORE_LE32(addr, val) (*(u32 *)addr = val)
+
+#define MAX_FIFO_SIZE 16
+
+#define CIRCULAR_BUF_INC_IDX(idx) (idx = (idx + 1) & (MAX_FIFO_SIZE - 1))
+
+#define MTTY_VFIO_PCI_OFFSET_SHIFT 40
+
+#define MTTY_VFIO_PCI_OFFSET_TO_INDEX(off) (off >> MTTY_VFIO_PCI_OFFSET_SHIFT)
+#define MTTY_VFIO_PCI_INDEX_TO_OFFSET(index) \
+ ((u64)(index) << MTTY_VFIO_PCI_OFFSET_SHIFT)
+#define MTTY_VFIO_PCI_OFFSET_MASK \
+ (((u64)(1) << MTTY_VFIO_PCI_OFFSET_SHIFT) - 1)
+#define MAX_MTTYS 24
+
+/*
+ * Global Structures
+ */
+
+struct mtty_dev {
+ dev_t vd_devt;
+ struct class *vd_class;
+ struct cdev vd_cdev;
+ struct idr vd_idr;
+ struct device dev;
+} mtty_dev;
+
+struct mdev_region_info {
+ u64 start;
+ u64 phys_start;
+ u32 size;
+ u64 vfio_offset;
+};
+
+#if defined(DEBUG_REGS)
+const char *wr_reg[] = {
+ "TX",
+ "IER",
+ "FCR",
+ "LCR",
+ "MCR",
+ "LSR",
+ "MSR",
+ "SCR"
+};
+
+const char *rd_reg[] = {
+ "RX",
+ "IER",
+ "IIR",
+ "LCR",
+ "MCR",
+ "LSR",
+ "MSR",
+ "SCR"
+};
+#endif
+
+/* loop back buffer */
+struct rxtx {
+ u8 fifo[MAX_FIFO_SIZE];
+ u8 head, tail;
+ u8 count;
+};
+
+struct serial_port {
+ u8 uart_reg[8]; /* 8 registers */
+ struct rxtx rxtx; /* loop back buffer */
+ bool dlab;
+ bool overrun;
+ u16 divisor;
+ u8 fcr; /* FIFO control register */
+ u8 max_fifo_size;
+ u8 intr_trigger_level; /* interrupt trigger level */
+};
+
+/* State of each mdev device */
+struct mdev_state {
+ int irq_fd;
+ struct eventfd_ctx *intx_evtfd;
+ struct eventfd_ctx *msi_evtfd;
+ int irq_index;
+ u8 *vconfig;
+ struct mutex ops_lock;
+ struct mdev_device *mdev;
+ struct mdev_region_info region_info[VFIO_PCI_NUM_REGIONS];
+ u32 bar_mask[VFIO_PCI_NUM_REGIONS];
+ struct list_head next;
+ struct serial_port s[2];
+ struct mutex rxtx_lock;
+ struct vfio_device_info dev_info;
+ int nr_ports;
+};
+
+struct mutex mdev_list_lock;
+struct list_head mdev_devices_list;
+
+static const struct file_operations vd_fops = {
+ .owner = THIS_MODULE,
+};
+
+/* function prototypes */
+
+static int mtty_trigger_interrupt(uuid_le uuid);
+
+/* Helper functions */
+static struct mdev_state *find_mdev_state_by_uuid(uuid_le uuid)
+{
+ struct mdev_state *mds;
+
+ list_for_each_entry(mds, &mdev_devices_list, next) {
+ if (uuid_le_cmp(mds->mdev->uuid, uuid) == 0)
+ return mds;
+ }
+
+ return NULL;
+}
+
+void dump_buffer(char *buf, uint32_t count)
+{
+#if defined(DEBUG)
+ int i;
+
+ pr_info("Buffer:\n");
+ for (i = 0; i < count; i++) {
+ pr_info("%2x ", *(buf + i));
+ if ((i + 1) % 16 == 0)
+ pr_info("\n");
+ }
+#endif
+}
+
+static void mtty_create_config_space(struct mdev_state *mdev_state)
+{
+ /* PCI dev ID */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x0], 0x32534348);
+
+ /* Control: I/O+, Mem-, BusMaster- */
+ STORE_LE16((u16 *) &mdev_state->vconfig[0x4], 0x0001);
+
+ /* Status: capabilities list absent */
+ STORE_LE16((u16 *) &mdev_state->vconfig[0x6], 0x0200);
+
+ /* Rev ID */
+ mdev_state->vconfig[0x8] = 0x10;
+
+ /* programming interface class : 16550-compatible serial controller */
+ mdev_state->vconfig[0x9] = 0x02;
+
+ /* Sub class : 00 */
+ mdev_state->vconfig[0xa] = 0x00;
+
+ /* Base class : Simple Communication controllers */
+ mdev_state->vconfig[0xb] = 0x07;
+
+ /* base address registers */
+ /* BAR0: IO space */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x10], 0x000001);
+ mdev_state->bar_mask[0] = ~(MTTY_IO_BAR_SIZE) + 1;
+
+ if (mdev_state->nr_ports == 2) {
+ /* BAR1: IO space */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x14], 0x000001);
+ mdev_state->bar_mask[1] = ~(MTTY_IO_BAR_SIZE) + 1;
+ }
+
+ /* Subsystem ID */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x2c], 0x32534348);
+
+ mdev_state->vconfig[0x34] = 0x00; /* Cap Ptr */
+ mdev_state->vconfig[0x3d] = 0x01; /* interrupt pin (INTA#) */
+
+ /* Vendor specific data */
+ mdev_state->vconfig[0x40] = 0x23;
+ mdev_state->vconfig[0x43] = 0x80;
+ mdev_state->vconfig[0x44] = 0x23;
+ mdev_state->vconfig[0x48] = 0x23;
+ mdev_state->vconfig[0x4c] = 0x23;
+
+ mdev_state->vconfig[0x60] = 0x50;
+ mdev_state->vconfig[0x61] = 0x43;
+ mdev_state->vconfig[0x62] = 0x49;
+ mdev_state->vconfig[0x63] = 0x20;
+ mdev_state->vconfig[0x64] = 0x53;
+ mdev_state->vconfig[0x65] = 0x65;
+ mdev_state->vconfig[0x66] = 0x72;
+ mdev_state->vconfig[0x67] = 0x69;
+ mdev_state->vconfig[0x68] = 0x61;
+ mdev_state->vconfig[0x69] = 0x6c;
+ mdev_state->vconfig[0x6a] = 0x2f;
+ mdev_state->vconfig[0x6b] = 0x55;
+ mdev_state->vconfig[0x6c] = 0x41;
+ mdev_state->vconfig[0x6d] = 0x52;
+ mdev_state->vconfig[0x6e] = 0x54;
+}
+
+static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
+ char *buf, u32 count)
+{
+ u32 cfg_addr, bar_mask, bar_index = 0;
+
+ switch (offset) {
+ case 0x04: /* device control */
+ case 0x06: /* device status */
+ /* do nothing */
+ break;
+ case 0x3c: /* interrupt line */
+ mdev_state->vconfig[0x3c] = buf[0];
+ break;
+ case 0x3d:
+ /*
+ * Interrupt Pin is hardwired to INTA.
+ * This field is write protected by hardware
+ */
+ break;
+ case 0x10: /* BAR0 */
+ case 0x14: /* BAR1 */
+ if (offset == 0x10)
+ bar_index = 0;
+ else if (offset == 0x14)
+ bar_index = 1;
+
+ if ((mdev_state->nr_ports == 1) && (bar_index == 1)) {
+ STORE_LE32(&mdev_state->vconfig[offset], 0);
+ break;
+ }
+
+ cfg_addr = *(u32 *)buf;
+ pr_info("BAR%d addr 0x%x\n", bar_index, cfg_addr);
+
+ if (cfg_addr == 0xffffffff) {
+ bar_mask = mdev_state->bar_mask[bar_index];
+ cfg_addr = (cfg_addr & bar_mask);
+ }
+
+ cfg_addr |= (mdev_state->vconfig[offset] & 0x3ul);
+ STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
+ break;
+ case 0x18: /* BAR2 */
+ case 0x1c: /* BAR3 */
+ case 0x20: /* BAR4 */
+ STORE_LE32(&mdev_state->vconfig[offset], 0);
+ break;
+ default:
+ pr_info("PCI config write @0x%x of %d bytes not handled\n",
+ offset, count);
+ break;
+ }
+}
+
+static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
+ u16 offset, char *buf, u32 count)
+{
+ u8 data = *buf;
+
+ /* Handle data written by guest */
+ switch (offset) {
+ case UART_TX:
+ /* if DLAB set, data is LSB of divisor */
+ if (mdev_state->s[index].dlab) {
+ mdev_state->s[index].divisor |= data;
+ break;
+ }
+
+ mutex_lock(&mdev_state->rxtx_lock);
+
+ /* save in TX buffer */
+ if (mdev_state->s[index].rxtx.count <
+ mdev_state->s[index].max_fifo_size) {
+ mdev_state->s[index].rxtx.fifo[
+ mdev_state->s[index].rxtx.head] = data;
+ mdev_state->s[index].rxtx.count++;
+ CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.head);
+ mdev_state->s[index].overrun = false;
+
+ /*
+ * Trigger interrupt if receive data interrupt is
+ * enabled and fifo reached trigger level
+ */
+ if ((mdev_state->s[index].uart_reg[UART_IER] &
+ UART_IER_RDI) &&
+ (mdev_state->s[index].rxtx.count ==
+ mdev_state->s[index].intr_trigger_level)) {
+ /* trigger interrupt */
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: Fifo level trigger\n",
+ index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ } else {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: Buffer Overflow\n", index);
+#endif
+ mdev_state->s[index].overrun = true;
+
+ /*
+ * Trigger interrupt if receiver line status interrupt
+ * is enabled
+ */
+ if (mdev_state->s[index].uart_reg[UART_IER] &
+ UART_IER_RLSI)
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ mutex_unlock(&mdev_state->rxtx_lock);
+ break;
+
+ case UART_IER:
+ /* if DLAB set, data is MSB of divisor */
+ if (mdev_state->s[index].dlab)
+ mdev_state->s[index].divisor |= (u16)data << 8;
+ else {
+ mdev_state->s[index].uart_reg[offset] = data;
+ mutex_lock(&mdev_state->rxtx_lock);
+ if ((data & UART_IER_THRI) &&
+ (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail)) {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: IER_THRI write\n",
+ index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+
+ mutex_unlock(&mdev_state->rxtx_lock);
+ }
+
+ break;
+
+ case UART_FCR:
+ mdev_state->s[index].fcr = data;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ if (data & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT)) {
+ /* clear loop back FIFO */
+ mdev_state->s[index].rxtx.count = 0;
+ mdev_state->s[index].rxtx.head = 0;
+ mdev_state->s[index].rxtx.tail = 0;
+ }
+ mutex_unlock(&mdev_state->rxtx_lock);
+
+ switch (data & UART_FCR_TRIGGER_MASK) {
+ case UART_FCR_TRIGGER_1:
+ mdev_state->s[index].intr_trigger_level = 1;
+ break;
+
+ case UART_FCR_TRIGGER_4:
+ mdev_state->s[index].intr_trigger_level = 4;
+ break;
+
+ case UART_FCR_TRIGGER_8:
+ mdev_state->s[index].intr_trigger_level = 8;
+ break;
+
+ case UART_FCR_TRIGGER_14:
+ mdev_state->s[index].intr_trigger_level = 14;
+ break;
+ }
+
+ /*
+ * Set trigger level to 1 otherwise or implement timer with
+ * timeout of 4 characters and on expiring that timer set
+ * Recevice data timeout in IIR register
+ */
+ mdev_state->s[index].intr_trigger_level = 1;
+ if (data & UART_FCR_ENABLE_FIFO)
+ mdev_state->s[index].max_fifo_size = MAX_FIFO_SIZE;
+ else {
+ mdev_state->s[index].max_fifo_size = 1;
+ mdev_state->s[index].intr_trigger_level = 1;
+ }
+
+ break;
+
+ case UART_LCR:
+ if (data & UART_LCR_DLAB) {
+ mdev_state->s[index].dlab = true;
+ mdev_state->s[index].divisor = 0;
+ } else
+ mdev_state->s[index].dlab = false;
+
+ mdev_state->s[index].uart_reg[offset] = data;
+ break;
+
+ case UART_MCR:
+ mdev_state->s[index].uart_reg[offset] = data;
+
+ if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
+ (data & UART_MCR_OUT2)) {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: MCR_OUT2 write\n", index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+
+ if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
+ (data & (UART_MCR_RTS | UART_MCR_DTR))) {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: MCR RTS/DTR write\n", index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ break;
+
+ case UART_LSR:
+ case UART_MSR:
+ /* do nothing */
+ break;
+
+ case UART_SCR:
+ mdev_state->s[index].uart_reg[offset] = data;
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void handle_bar_read(unsigned int index, struct mdev_state *mdev_state,
+ u16 offset, char *buf, u32 count)
+{
+ /* Handle read requests by guest */
+ switch (offset) {
+ case UART_RX:
+ /* if DLAB set, data is LSB of divisor */
+ if (mdev_state->s[index].dlab) {
+ *buf = (u8)mdev_state->s[index].divisor;
+ break;
+ }
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* return data in tx buffer */
+ if (mdev_state->s[index].rxtx.head !=
+ mdev_state->s[index].rxtx.tail) {
+ *buf = mdev_state->s[index].rxtx.fifo[
+ mdev_state->s[index].rxtx.tail];
+ mdev_state->s[index].rxtx.count--;
+ CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.tail);
+ }
+
+ if (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail) {
+ /*
+ * Trigger interrupt if tx buffer empty interrupt is
+ * enabled and fifo is empty
+ */
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: Buffer Empty\n", index);
+#endif
+ if (mdev_state->s[index].uart_reg[UART_IER] &
+ UART_IER_THRI)
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ mutex_unlock(&mdev_state->rxtx_lock);
+
+ break;
+
+ case UART_IER:
+ if (mdev_state->s[index].dlab) {
+ *buf = (u8)(mdev_state->s[index].divisor >> 8);
+ break;
+ }
+ *buf = mdev_state->s[index].uart_reg[offset] & 0x0f;
+ break;
+
+ case UART_IIR:
+ {
+ u8 ier = mdev_state->s[index].uart_reg[UART_IER];
+ *buf = 0;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* Interrupt priority 1: Parity, overrun, framing or break */
+ if ((ier & UART_IER_RLSI) && mdev_state->s[index].overrun)
+ *buf |= UART_IIR_RLSI;
+
+ /* Interrupt priority 2: Fifo trigger level reached */
+ if ((ier & UART_IER_RDI) &&
+ (mdev_state->s[index].rxtx.count ==
+ mdev_state->s[index].intr_trigger_level))
+ *buf |= UART_IIR_RDI;
+
+ /* Interrupt priotiry 3: transmitter holding register empty */
+ if ((ier & UART_IER_THRI) &&
+ (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail))
+ *buf |= UART_IIR_THRI;
+
+ /* Interrupt priotiry 4: Modem status: CTS, DSR, RI or DCD */
+ if ((ier & UART_IER_MSI) &&
+ (mdev_state->s[index].uart_reg[UART_MCR] &
+ (UART_MCR_RTS | UART_MCR_DTR)))
+ *buf |= UART_IIR_MSI;
+
+ /* bit0: 0=> interrupt pending, 1=> no interrupt is pending */
+ if (*buf == 0)
+ *buf = UART_IIR_NO_INT;
+
+ /* set bit 6 & 7 to be 16550 compatible */
+ *buf |= 0xC0;
+ mutex_unlock(&mdev_state->rxtx_lock);
+ }
+ break;
+
+ case UART_LCR:
+ case UART_MCR:
+ *buf = mdev_state->s[index].uart_reg[offset];
+ break;
+
+ case UART_LSR:
+ {
+ u8 lsr = 0;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* atleast one char in FIFO */
+ if (mdev_state->s[index].rxtx.head !=
+ mdev_state->s[index].rxtx.tail)
+ lsr |= UART_LSR_DR;
+
+ /* if FIFO overrun */
+ if (mdev_state->s[index].overrun)
+ lsr |= UART_LSR_OE;
+
+ /* transmit FIFO empty and tramsitter empty */
+ if (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail)
+ lsr |= UART_LSR_TEMT | UART_LSR_THRE;
+
+ mutex_unlock(&mdev_state->rxtx_lock);
+ *buf = lsr;
+ break;
+ }
+ case UART_MSR:
+ *buf = UART_MSR_DSR | UART_MSR_DDSR | UART_MSR_DCD;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* if AFE is 1 and FIFO have space, set CTS bit */
+ if (mdev_state->s[index].uart_reg[UART_MCR] &
+ UART_MCR_AFE) {
+ if (mdev_state->s[index].rxtx.count <
+ mdev_state->s[index].max_fifo_size)
+ *buf |= UART_MSR_CTS | UART_MSR_DCTS;
+ } else
+ *buf |= UART_MSR_CTS | UART_MSR_DCTS;
+ mutex_unlock(&mdev_state->rxtx_lock);
+
+ break;
+
+ case UART_SCR:
+ *buf = mdev_state->s[index].uart_reg[offset];
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void mdev_read_base(struct mdev_state *mdev_state)
+{
+ int index, pos;
+ u32 start_lo, start_hi;
+ u32 mem_type;
+
+ pos = PCI_BASE_ADDRESS_0;
+
+ for (index = 0; index <= VFIO_PCI_BAR5_REGION_INDEX; index++) {
+
+ if (!mdev_state->region_info[index].size)
+ continue;
+
+ start_lo = (*(u32 *)(mdev_state->vconfig + pos)) &
+ PCI_BASE_ADDRESS_MEM_MASK;
+ mem_type = (*(u32 *)(mdev_state->vconfig + pos)) &
+ PCI_BASE_ADDRESS_MEM_TYPE_MASK;
+
+ switch (mem_type) {
+ case PCI_BASE_ADDRESS_MEM_TYPE_64:
+ start_hi = (*(u32 *)(mdev_state->vconfig + pos + 4));
+ pos += 4;
+ break;
+ case PCI_BASE_ADDRESS_MEM_TYPE_32:
+ case PCI_BASE_ADDRESS_MEM_TYPE_1M:
+ /* 1M mem BAR treated as 32-bit BAR */
+ default:
+ /* mem unknown type treated as 32-bit BAR */
+ start_hi = 0;
+ break;
+ }
+ pos += 4;
+ mdev_state->region_info[index].start = ((u64)start_hi << 32) |
+ start_lo;
+ }
+}
+
+static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
+ loff_t pos, bool is_write)
+{
+ struct mdev_state *mdev_state;
+ unsigned int index;
+ loff_t offset;
+ int ret = 0;
+
+ if (!mdev || !buf)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state) {
+ pr_err("%s mdev_state not found\n", __func__);
+ return -EINVAL;
+ }
+
+ mutex_lock(&mdev_state->ops_lock);
+
+ index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(pos);
+ offset = pos & MTTY_VFIO_PCI_OFFSET_MASK;
+ switch (index) {
+ case VFIO_PCI_CONFIG_REGION_INDEX:
+
+#if defined(DEBUG)
+ pr_info("%s: PCI config space %s at offset 0x%llx\n",
+ __func__, is_write ? "write" : "read", offset);
+#endif
+ if (is_write) {
+ dump_buffer(buf, count);
+ handle_pci_cfg_write(mdev_state, offset, buf, count);
+ } else {
+ memcpy(buf, (mdev_state->vconfig + offset), count);
+ dump_buffer(buf, count);
+ }
+
+ break;
+
+ case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
+ if (!mdev_state->region_info[index].start)
+ mdev_read_base(mdev_state);
+
+ if (is_write) {
+ dump_buffer(buf, count);
+
+#if defined(DEBUG_REGS)
+ pr_info("%s: BAR%d WR @0x%llx %s val:0x%02x dlab:%d\n",
+ __func__, index, offset, wr_reg[offset],
+ (u8)*buf, mdev_state->s[index].dlab);
+#endif
+ handle_bar_write(index, mdev_state, offset, buf, count);
+ } else {
+ handle_bar_read(index, mdev_state, offset, buf, count);
+ dump_buffer(buf, count);
+
+#if defined(DEBUG_REGS)
+ pr_info("%s: BAR%d RD @0x%llx %s val:0x%02x dlab:%d\n",
+ __func__, index, offset, rd_reg[offset],
+ (u8)*buf, mdev_state->s[index].dlab);
+#endif
+ }
+ break;
+
+ default:
+ ret = -1;
+ goto accessfailed;
+ }
+
+ ret = count;
+
+
+accessfailed:
+ mutex_unlock(&mdev_state->ops_lock);
+
+ return ret;
+}
+
+int mtty_create(struct kobject *kobj, struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state;
+ char name[MTTY_STRING_LEN];
+ int nr_ports = 0, i;
+
+ if (!mdev)
+ return -EINVAL;
+
+ for (i = 0; i < 2; i++) {
+ snprintf(name, MTTY_STRING_LEN, "%s-%d",
+ dev_driver_string(mdev->parent->dev), i + 1);
+ if (!strcmp(kobj->name, name)) {
+ nr_ports = i + 1;
+ break;
+ }
+ }
+
+ if (!nr_ports)
+ return -EINVAL;
+
+ mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
+ if (mdev_state == NULL)
+ return -ENOMEM;
+
+ mdev_state->nr_ports = nr_ports;
+ mdev_state->irq_index = -1;
+ mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
+ mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
+ mutex_init(&mdev_state->rxtx_lock);
+ mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
+
+ if (mdev_state->vconfig == NULL) {
+ kfree(mdev_state);
+ return -ENOMEM;
+ }
+
+ mutex_init(&mdev_state->ops_lock);
+ mdev_state->mdev = mdev;
+ mdev_set_drvdata(mdev, mdev_state);
+
+ mtty_create_config_space(mdev_state);
+
+ mutex_lock(&mdev_list_lock);
+ list_add(&mdev_state->next, &mdev_devices_list);
+ mutex_unlock(&mdev_list_lock);
+
+ return 0;
+}
+
+int mtty_remove(struct mdev_device *mdev)
+{
+ struct mdev_state *mds, *tmp_mds;
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ int ret = -EINVAL;
+
+ mutex_lock(&mdev_list_lock);
+ list_for_each_entry_safe(mds, tmp_mds, &mdev_devices_list, next) {
+ if (mdev_state == mds) {
+ list_del(&mdev_state->next);
+ mdev_set_drvdata(mdev, NULL);
+ kfree(mdev_state->vconfig);
+ kfree(mdev_state);
+ ret = 0;
+ break;
+ }
+ }
+ mutex_unlock(&mdev_list_lock);
+
+ return ret;
+}
+
+int mtty_reset(struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -EINVAL;
+
+ pr_info("%s: called\n", __func__);
+
+ return 0;
+}
+
+ssize_t mtty_read(struct mdev_device *mdev, char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ unsigned int done = 0;
+ int ret;
+
+ while (count) {
+ size_t filled;
+
+ if (count >= 4 && !(*ppos % 4)) {
+ u32 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 4;
+ } else if (count >= 2 && !(*ppos % 2)) {
+ u16 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 2;
+ } else {
+ u8 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 1;
+ }
+
+ count -= filled;
+ done += filled;
+ *ppos += filled;
+ buf += filled;
+ }
+
+ return done;
+
+read_err:
+ return -EFAULT;
+}
+
+ssize_t mtty_write(struct mdev_device *mdev, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ unsigned int done = 0;
+ int ret;
+
+ while (count) {
+ size_t filled;
+
+ if (count >= 4 && !(*ppos % 4)) {
+ u32 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 4;
+ } else if (count >= 2 && !(*ppos % 2)) {
+ u16 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 2;
+ } else {
+ u8 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 1;
+ }
+ count -= filled;
+ done += filled;
+ *ppos += filled;
+ buf += filled;
+ }
+
+ return done;
+write_err:
+ return -EFAULT;
+}
+
+static int mtty_set_irqs(struct mdev_device *mdev, uint32_t flags,
+ unsigned int index, unsigned int start,
+ unsigned int count, void *data)
+{
+ int ret = 0;
+ struct mdev_state *mdev_state;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -EINVAL;
+
+ mutex_lock(&mdev_state->ops_lock);
+ switch (index) {
+ case VFIO_PCI_INTX_IRQ_INDEX:
+ switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+ case VFIO_IRQ_SET_ACTION_MASK:
+ case VFIO_IRQ_SET_ACTION_UNMASK:
+ break;
+ case VFIO_IRQ_SET_ACTION_TRIGGER:
+ {
+ if (flags & VFIO_IRQ_SET_DATA_NONE) {
+ pr_info("%s: disable INTx\n", __func__);
+ if (mdev_state->intx_evtfd)
+ eventfd_ctx_put(mdev_state->intx_evtfd);
+ break;
+ }
+
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ int fd = *(int *)data;
+
+ if (fd > 0) {
+ struct eventfd_ctx *evt;
+
+ evt = eventfd_ctx_fdget(fd);
+ if (IS_ERR(evt)) {
+ ret = PTR_ERR(evt);
+ break;
+ }
+ mdev_state->intx_evtfd = evt;
+ mdev_state->irq_fd = fd;
+ mdev_state->irq_index = index;
+ break;
+ }
+ }
+ break;
+ }
+ }
+ break;
+ case VFIO_PCI_MSI_IRQ_INDEX:
+ switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+ case VFIO_IRQ_SET_ACTION_MASK:
+ case VFIO_IRQ_SET_ACTION_UNMASK:
+ break;
+ case VFIO_IRQ_SET_ACTION_TRIGGER:
+ if (flags & VFIO_IRQ_SET_DATA_NONE) {
+ if (mdev_state->msi_evtfd)
+ eventfd_ctx_put(mdev_state->msi_evtfd);
+ pr_info("%s: disable MSI\n", __func__);
+ mdev_state->irq_index = VFIO_PCI_INTX_IRQ_INDEX;
+ break;
+ }
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ int fd = *(int *)data;
+ struct eventfd_ctx *evt;
+
+ if (fd <= 0)
+ break;
+
+ if (mdev_state->msi_evtfd)
+ break;
+
+ evt = eventfd_ctx_fdget(fd);
+ if (IS_ERR(evt)) {
+ ret = PTR_ERR(evt);
+ break;
+ }
+ mdev_state->msi_evtfd = evt;
+ mdev_state->irq_fd = fd;
+ mdev_state->irq_index = index;
+ }
+ break;
+ }
+ break;
+ case VFIO_PCI_MSIX_IRQ_INDEX:
+ pr_info("%s: MSIX_IRQ\n", __func__);
+ break;
+ case VFIO_PCI_ERR_IRQ_INDEX:
+ pr_info("%s: ERR_IRQ\n", __func__);
+ break;
+ case VFIO_PCI_REQ_IRQ_INDEX:
+ pr_info("%s: REQ_IRQ\n", __func__);
+ break;
+ }
+
+ mutex_unlock(&mdev_state->ops_lock);
+ return ret;
+}
+
+static int mtty_trigger_interrupt(uuid_le uuid)
+{
+ int ret = -1;
+ struct mdev_state *mdev_state;
+
+ mdev_state = find_mdev_state_by_uuid(uuid);
+
+ if (!mdev_state) {
+ pr_info("%s: mdev not found\n", __func__);
+ return -EINVAL;
+ }
+
+ if ((mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX) &&
+ (!mdev_state->msi_evtfd))
+ return -EINVAL;
+ else if ((mdev_state->irq_index == VFIO_PCI_INTX_IRQ_INDEX) &&
+ (!mdev_state->intx_evtfd)) {
+ pr_info("%s: Intr eventfd not found\n", __func__);
+ return -EINVAL;
+ }
+
+ if (mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX)
+ ret = eventfd_signal(mdev_state->msi_evtfd, 1);
+ else
+ ret = eventfd_signal(mdev_state->intx_evtfd, 1);
+
+#if defined(DEBUG_INTR)
+ pr_info("Intx triggered\n");
+#endif
+ if (ret != 1)
+ pr_err("%s: eventfd signal failed (%d)\n", __func__, ret);
+
+ return ret;
+}
+
+int mtty_get_region_info(struct mdev_device *mdev,
+ struct vfio_region_info *region_info,
+ u16 *cap_type_id, void **cap_type)
+{
+ unsigned int size = 0;
+ struct mdev_state *mdev_state;
+ int bar_index;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -EINVAL;
+
+ mutex_lock(&mdev_state->ops_lock);
+ bar_index = region_info->index;
+
+ switch (bar_index) {
+ case VFIO_PCI_CONFIG_REGION_INDEX:
+ size = MTTY_CONFIG_SPACE_SIZE;
+ break;
+ case VFIO_PCI_BAR0_REGION_INDEX:
+ size = MTTY_IO_BAR_SIZE;
+ break;
+ case VFIO_PCI_BAR1_REGION_INDEX:
+ if (mdev_state->nr_ports == 2)
+ size = MTTY_IO_BAR_SIZE;
+ break;
+ default:
+ size = 0;
+ break;
+ }
+
+ mdev_state->region_info[bar_index].size = size;
+ mdev_state->region_info[bar_index].vfio_offset =
+ MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
+
+ region_info->size = size;
+ region_info->offset = MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
+ region_info->flags = VFIO_REGION_INFO_FLAG_READ |
+ VFIO_REGION_INFO_FLAG_WRITE;
+ mutex_unlock(&mdev_state->ops_lock);
+ return 0;
+}
+
+int mtty_get_irq_info(struct mdev_device *mdev, struct vfio_irq_info *irq_info)
+{
+ switch (irq_info->index) {
+ case VFIO_PCI_INTX_IRQ_INDEX:
+ case VFIO_PCI_MSI_IRQ_INDEX:
+ case VFIO_PCI_REQ_IRQ_INDEX:
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ irq_info->flags = VFIO_IRQ_INFO_EVENTFD;
+ irq_info->count = 1;
+
+ if (irq_info->index == VFIO_PCI_INTX_IRQ_INDEX)
+ irq_info->flags |= (VFIO_IRQ_INFO_MASKABLE |
+ VFIO_IRQ_INFO_AUTOMASKED);
+ else
+ irq_info->flags |= VFIO_IRQ_INFO_NORESIZE;
+
+ return 0;
+}
+
+int mtty_get_device_info(struct mdev_device *mdev,
+ struct vfio_device_info *dev_info)
+{
+ dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
+ dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
+ dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
+
+ return 0;
+}
+
+static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret = 0;
+ unsigned long minsz;
+ struct mdev_state *mdev_state;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -ENODEV;
+
+ switch (cmd) {
+ case VFIO_DEVICE_GET_INFO:
+ {
+ struct vfio_device_info info;
+
+ minsz = offsetofend(struct vfio_device_info, num_irqs);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ ret = mtty_get_device_info(mdev, &info);
+ if (ret)
+ return ret;
+
+ memcpy(&mdev_state->dev_info, &info, sizeof(info));
+
+ return copy_to_user((void __user *)arg, &info, minsz);
+ }
+ case VFIO_DEVICE_GET_REGION_INFO:
+ {
+ struct vfio_region_info info;
+ u16 cap_type_id = 0;
+ void *cap_type = NULL;
+
+ minsz = offsetofend(struct vfio_region_info, offset);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ ret = mtty_get_region_info(mdev, &info, &cap_type_id,
+ &cap_type);
+ if (ret)
+ return ret;
+
+ return copy_to_user((void __user *)arg, &info, minsz);
+ }
+
+ case VFIO_DEVICE_GET_IRQ_INFO:
+ {
+ struct vfio_irq_info info;
+
+ minsz = offsetofend(struct vfio_irq_info, count);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if ((info.argsz < minsz) ||
+ (info.index >= mdev_state->dev_info.num_irqs))
+ return -EINVAL;
+
+ ret = mtty_get_irq_info(mdev, &info);
+ if (ret)
+ return ret;
+
+ if (info.count == -1)
+ return -EINVAL;
+
+ return copy_to_user((void __user *)arg, &info, minsz);
+ }
+ case VFIO_DEVICE_SET_IRQS:
+ {
+ struct vfio_irq_set hdr;
+ u8 *data = NULL, *ptr = NULL;
+ size_t data_size = 0;
+
+ minsz = offsetofend(struct vfio_irq_set, count);
+
+ if (copy_from_user(&hdr, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ ret = vfio_set_irqs_validate_and_prepare(&hdr,
+ mdev_state->dev_info.num_irqs,
+ VFIO_PCI_NUM_IRQS,
+ &data_size);
+ if (ret)
+ return ret;
+
+ if (data_size) {
+ ptr = data = memdup_user((void __user *)(arg + minsz),
+ data_size);
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+ }
+
+ ret = mtty_set_irqs(mdev, hdr.flags, hdr.index, hdr.start,
+ hdr.count, data);
+
+ kfree(ptr);
+ return ret;
+ }
+ case VFIO_DEVICE_RESET:
+ return mtty_reset(mdev);
+ }
+ return -ENOTTY;
+}
+
+int mtty_open(struct mdev_device *mdev)
+{
+ pr_info("%s\n", __func__);
+ return 0;
+}
+
+void mtty_close(struct mdev_device *mdev)
+{
+ pr_info("%s\n", __func__);
+}
+
+static ssize_t
+sample_mtty_dev_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "This is phy device\n");
+}
+
+static DEVICE_ATTR_RO(sample_mtty_dev);
+
+static struct attribute *mtty_dev_attrs[] = {
+ &dev_attr_sample_mtty_dev.attr,
+ NULL,
+};
+
+static const struct attribute_group mtty_dev_group = {
+ .name = "mtty_dev",
+ .attrs = mtty_dev_attrs,
+};
+
+const struct attribute_group *mtty_dev_groups[] = {
+ &mtty_dev_group,
+ NULL,
+};
+
+static ssize_t
+sample_mdev_dev_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ if (mdev)
+ return sprintf(buf, "This is MDEV %s\n", dev_name(&mdev->dev));
+
+ return sprintf(buf, "\n");
+}
+
+static DEVICE_ATTR_RO(sample_mdev_dev);
+
+static struct attribute *mdev_dev_attrs[] = {
+ &dev_attr_sample_mdev_dev.attr,
+ NULL,
+};
+
+static const struct attribute_group mdev_dev_group = {
+ .name = "vendor",
+ .attrs = mdev_dev_attrs,
+};
+
+const struct attribute_group *mdev_dev_groups[] = {
+ &mdev_dev_group,
+ NULL,
+};
+
+static ssize_t
+name_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+ char name[MTTY_STRING_LEN];
+ int i;
+ const char *name_str[2] = {"Single port serial", "Dual port serial"};
+
+ for (i = 0; i < 2; i++) {
+ snprintf(name, MTTY_STRING_LEN, "%s-%d",
+ dev_driver_string(dev), i + 1);
+ if (!strcmp(kobj->name, name))
+ return sprintf(buf, "%s\n", name_str[i]);
+ }
+
+ return -EINVAL;
+}
+
+MDEV_TYPE_ATTR_RO(name);
+
+static ssize_t
+available_instances_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+ char name[MTTY_STRING_LEN];
+ int i;
+ struct mdev_state *mds;
+ int ports = 0, used = 0;
+
+ for (i = 0; i < 2; i++) {
+ snprintf(name, MTTY_STRING_LEN, "%s-%d",
+ dev_driver_string(dev), i + 1);
+ if (!strcmp(kobj->name, name)) {
+ ports = i + 1;
+ break;
+ }
+ }
+
+ if (!ports)
+ return -EINVAL;
+
+ list_for_each_entry(mds, &mdev_devices_list, next)
+ used += mds->nr_ports;
+
+ return sprintf(buf, "%d\n", (MAX_MTTYS - used)/ports);
+}
+
+MDEV_TYPE_ATTR_RO(available_instances);
+
+
+static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
+ char *buf)
+{
+ return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
+}
+
+MDEV_TYPE_ATTR_RO(device_api);
+
+static struct attribute *mdev_types_attrs[] = {
+ &mdev_type_attr_name.attr,
+ &mdev_type_attr_device_api.attr,
+ &mdev_type_attr_available_instances.attr,
+ NULL,
+};
+
+static struct attribute_group mdev_type_group1 = {
+ .name = "1",
+ .attrs = mdev_types_attrs,
+};
+
+static struct attribute_group mdev_type_group2 = {
+ .name = "2",
+ .attrs = mdev_types_attrs,
+};
+
+struct attribute_group *mdev_type_groups[] = {
+ &mdev_type_group1,
+ &mdev_type_group2,
+ NULL,
+};
+
+struct parent_ops mdev_fops = {
+ .owner = THIS_MODULE,
+ .dev_attr_groups = mtty_dev_groups,
+ .mdev_attr_groups = mdev_dev_groups,
+ .supported_type_groups = mdev_type_groups,
+ .create = mtty_create,
+ .remove = mtty_remove,
+ .open = mtty_open,
+ .release = mtty_close,
+ .read = mtty_read,
+ .write = mtty_write,
+ .ioctl = mtty_ioctl,
+};
+
+static void mtty_device_release(struct device *dev)
+{
+ dev_dbg(dev, "mtty: released\n");
+}
+
+static int __init mtty_dev_init(void)
+{
+ int ret = 0;
+
+ pr_info("mtty_dev: %s\n", __func__);
+
+ memset(&mtty_dev, 0, sizeof(mtty_dev));
+
+ idr_init(&mtty_dev.vd_idr);
+
+ ret = alloc_chrdev_region(&mtty_dev.vd_devt, 0, MINORMASK, MTTY_NAME);
+
+ if (ret < 0) {
+ pr_err("Error: failed to register mtty_dev, err:%d\n", ret);
+ return ret;
+ }
+
+ cdev_init(&mtty_dev.vd_cdev, &vd_fops);
+ cdev_add(&mtty_dev.vd_cdev, mtty_dev.vd_devt, MINORMASK);
+
+ pr_info("major_number:%d\n", MAJOR(mtty_dev.vd_devt));
+
+ mtty_dev.vd_class = class_create(THIS_MODULE, MTTY_CLASS_NAME);
+
+ if (IS_ERR(mtty_dev.vd_class)) {
+ pr_err("Error: failed to register mtty_dev class\n");
+ goto failed1;
+ }
+
+ mtty_dev.dev.class = mtty_dev.vd_class;
+ mtty_dev.dev.release = mtty_device_release;
+ dev_set_name(&mtty_dev.dev, "%s", MTTY_NAME);
+
+ ret = device_register(&mtty_dev.dev);
+ if (ret)
+ goto failed2;
+
+ if (mdev_register_device(&mtty_dev.dev, &mdev_fops) != 0)
+ goto failed3;
+
+ mutex_init(&mdev_list_lock);
+ INIT_LIST_HEAD(&mdev_devices_list);
+
+ goto all_done;
+
+failed3:
+
+ device_unregister(&mtty_dev.dev);
+failed2:
+ class_destroy(mtty_dev.vd_class);
+
+failed1:
+ cdev_del(&mtty_dev.vd_cdev);
+ unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
+
+all_done:
+ return ret;
+}
+
+static void __exit mtty_dev_exit(void)
+{
+ mtty_dev.dev.bus = NULL;
+ mdev_unregister_device(&mtty_dev.dev);
+
+ device_unregister(&mtty_dev.dev);
+ idr_destroy(&mtty_dev.vd_idr);
+ cdev_del(&mtty_dev.vd_cdev);
+ unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
+ class_destroy(mtty_dev.vd_class);
+ mtty_dev.vd_class = NULL;
+ pr_info("mtty_dev: Unloaded!\n");
+}
+
+module_init(mtty_dev_init)
+module_exit(mtty_dev_exit)
+
+MODULE_LICENSE("GPL");
+MODULE_INFO(supported, "Test driver that simulate serial port over PCI");
+MODULE_VERSION(VERSION_STRING);
+MODULE_AUTHOR(DRIVER_AUTHOR);
diff --git a/Documentation/vfio-mdev/vfio-mediated-device.txt b/Documentation/vfio-mdev/vfio-mediated-device.txt
index 69660aff86e3..9b4728436dc4 100644
--- a/Documentation/vfio-mdev/vfio-mediated-device.txt
+++ b/Documentation/vfio-mdev/vfio-mediated-device.txt
@@ -288,8 +288,109 @@ these callbacks are supported in the TYPE1 IOMMU module. To enable them for
other IOMMU backend modules, such as PPC64 sPAPR module, they need to provide
these two callback functions.
+Using the Sample Code
+=====================
+
+mtty.c in this folder is a sample driver program to demonstrate how to use the
+mediated device framework.
+
+The sample driver creates an mdev device that simulates a serial port over a PCI
+card.
+
+1. Build and load the mtty.ko module.
+
+ This step creates a dummy device, /sys/devices/virtual/mtty/mtty/
+
+ Files in this device directory in sysfs are similar to the following:
+
+ # tree /sys/devices/virtual/mtty/mtty/
+ /sys/devices/virtual/mtty/mtty/
+ |-- mdev_supported_types
+ | |-- mtty-1
+ | | |-- available_instances
+ | | |-- create
+ | | |-- device_api
+ | | |-- devices
+ | | `-- name
+ | `-- mtty-2
+ | |-- available_instances
+ | |-- create
+ | |-- device_api
+ | |-- devices
+ | `-- name
+ |-- mtty_dev
+ | `-- sample_mtty_dev
+ |-- power
+ | |-- autosuspend_delay_ms
+ | |-- control
+ | |-- runtime_active_time
+ | |-- runtime_status
+ | `-- runtime_suspended_time
+ |-- subsystem -> ../../../../class/mtty
+ `-- uevent
+
+2. Create a mediated device by using the dummy device that you created in the
+ previous step.
+
+ # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > \
+ /sys/devices/virtual/mtty/mtty/mdev_supported_types/mtty-2/create
+
+3. Add parameters to qemu-kvm.
+
+ -device vfio-pci,\
+ sysfsdev=/sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001
+
+4. Boot the VM.
+
+ In the Linux guest VM, with no hardware on the host, the device appears
+ as follows:
+
+ # lspci -s 00:05.0 -xxvv
+ 00:05.0 Serial controller: Device 4348:3253 (rev 10) (prog-if 02 [16550])
+ Subsystem: Device 4348:3253
+ Physical Slot: 5
+ Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr-
+ Stepping- SERR- FastB2B- DisINTx-
+ Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort-
+ <TAbort- <MAbort- >SERR- <PERR- INTx-
+ Interrupt: pin A routed to IRQ 10
+ Region 0: I/O ports at c150 [size=8]
+ Region 1: I/O ports at c158 [size=8]
+ Kernel driver in use: serial
+ 00: 48 43 53 32 01 00 00 02 10 02 00 07 00 00 00 00
+ 10: 51 c1 00 00 59 c1 00 00 00 00 00 00 00 00 00 00
+ 20: 00 00 00 00 00 00 00 00 00 00 00 00 48 43 53 32
+ 30: 00 00 00 00 00 00 00 00 00 00 00 00 0a 01 00 00
+
+ In the Linux guest VM, dmesg output for the device is as follows:
+
+ serial 0000:00:05.0: PCI INT A -> Link[LNKA] -> GSI 10 (level, high) -> IRQ
+10
+ 0000:00:05.0: ttyS1 at I/O 0xc150 (irq = 10) is a 16550A
+ 0000:00:05.0: ttyS2 at I/O 0xc158 (irq = 10) is a 16550A
+
+
+5. In the Linux guest VM, check the serial ports.
+
+ # setserial -g /dev/ttyS*
+ /dev/ttyS0, UART: 16550A, Port: 0x03f8, IRQ: 4
+ /dev/ttyS1, UART: 16550A, Port: 0xc150, IRQ: 10
+ /dev/ttyS2, UART: 16550A, Port: 0xc158, IRQ: 10
+
+6. Using a minicom or any terminal enulation program, open port /dev/ttyS1 or
+ /dev/ttyS2 with hardware flow control disabled.
+
+7. Type data on the minicom terminal or send data to the terminal emulation
+ program and read the data.
+
+ Data is loop backed from hosts mtty driver.
+
+8. Destroy the mediated device that you created.
+
+ # echo 1 > /sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001/remove
+
References
-----------
+==========
[1] See Documentation/vfio.txt for more information on VFIO.
[2] struct mdev_driver in include/linux/mdev.h
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* [Qemu-devel] [PATCH v10 19/19] docs: Sample driver to demonstrate how to use Mediated device framework.
@ 2016-10-26 21:29 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-26 21:29 UTC (permalink / raw)
To: alex.williamson, pbonzini, kraxel, cjia
Cc: qemu-devel, kvm, kevin.tian, jike.song, bjsdjshi, linux-kernel,
Kirti Wankhede
The Sample driver creates mdev device that simulates serial port over PCI
card.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Change-Id: I857f8f12f8b275f2498dfe8c628a5cdc7193b1b2
---
Documentation/vfio-mdev/Makefile | 13 +
Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
Documentation/vfio-mdev/vfio-mediated-device.txt | 103 +-
3 files changed, 1618 insertions(+), 1 deletion(-)
create mode 100644 Documentation/vfio-mdev/Makefile
create mode 100644 Documentation/vfio-mdev/mtty.c
diff --git a/Documentation/vfio-mdev/Makefile b/Documentation/vfio-mdev/Makefile
new file mode 100644
index 000000000000..a932edbe38eb
--- /dev/null
+++ b/Documentation/vfio-mdev/Makefile
@@ -0,0 +1,13 @@
+#
+# Makefile for mtty.c file
+#
+KERNEL_DIR:=/lib/modules/$(shell uname -r)/build
+
+obj-m:=mtty.o
+
+modules clean modules_install:
+ $(MAKE) -C $(KERNEL_DIR) SUBDIRS=$(PWD) $@
+
+default: modules
+
+module: modules
diff --git a/Documentation/vfio-mdev/mtty.c b/Documentation/vfio-mdev/mtty.c
new file mode 100644
index 000000000000..6c71d12288d1
--- /dev/null
+++ b/Documentation/vfio-mdev/mtty.c
@@ -0,0 +1,1503 @@
+/*
+ * Mediated virtual PCI serial host device driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ * Author: Neo Jia <cjia@nvidia.com>
+ * Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Sample driver that creates mdev device that simulates serial port over PCI
+ * card.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/cdev.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/uuid.h>
+#include <linux/vfio.h>
+#include <linux/iommu.h>
+#include <linux/sysfs.h>
+#include <linux/ctype.h>
+#include <linux/file.h>
+#include <linux/mdev.h>
+#include <linux/pci.h>
+#include <linux/serial.h>
+#include <uapi/linux/serial_reg.h>
+#include <linux/eventfd.h>
+/*
+ * #defines
+ */
+
+#define VERSION_STRING "0.1"
+#define DRIVER_AUTHOR "NVIDIA Corporation"
+
+#define MTTY_CLASS_NAME "mtty"
+
+#define MTTY_NAME "mtty"
+
+#define MTTY_STRING_LEN 16
+
+#define MTTY_CONFIG_SPACE_SIZE 0xff
+#define MTTY_IO_BAR_SIZE 0x8
+#define MTTY_MMIO_BAR_SIZE 0x100000
+
+#define STORE_LE16(addr, val) (*(u16 *)addr = val)
+#define STORE_LE32(addr, val) (*(u32 *)addr = val)
+
+#define MAX_FIFO_SIZE 16
+
+#define CIRCULAR_BUF_INC_IDX(idx) (idx = (idx + 1) & (MAX_FIFO_SIZE - 1))
+
+#define MTTY_VFIO_PCI_OFFSET_SHIFT 40
+
+#define MTTY_VFIO_PCI_OFFSET_TO_INDEX(off) (off >> MTTY_VFIO_PCI_OFFSET_SHIFT)
+#define MTTY_VFIO_PCI_INDEX_TO_OFFSET(index) \
+ ((u64)(index) << MTTY_VFIO_PCI_OFFSET_SHIFT)
+#define MTTY_VFIO_PCI_OFFSET_MASK \
+ (((u64)(1) << MTTY_VFIO_PCI_OFFSET_SHIFT) - 1)
+#define MAX_MTTYS 24
+
+/*
+ * Global Structures
+ */
+
+struct mtty_dev {
+ dev_t vd_devt;
+ struct class *vd_class;
+ struct cdev vd_cdev;
+ struct idr vd_idr;
+ struct device dev;
+} mtty_dev;
+
+struct mdev_region_info {
+ u64 start;
+ u64 phys_start;
+ u32 size;
+ u64 vfio_offset;
+};
+
+#if defined(DEBUG_REGS)
+const char *wr_reg[] = {
+ "TX",
+ "IER",
+ "FCR",
+ "LCR",
+ "MCR",
+ "LSR",
+ "MSR",
+ "SCR"
+};
+
+const char *rd_reg[] = {
+ "RX",
+ "IER",
+ "IIR",
+ "LCR",
+ "MCR",
+ "LSR",
+ "MSR",
+ "SCR"
+};
+#endif
+
+/* loop back buffer */
+struct rxtx {
+ u8 fifo[MAX_FIFO_SIZE];
+ u8 head, tail;
+ u8 count;
+};
+
+struct serial_port {
+ u8 uart_reg[8]; /* 8 registers */
+ struct rxtx rxtx; /* loop back buffer */
+ bool dlab;
+ bool overrun;
+ u16 divisor;
+ u8 fcr; /* FIFO control register */
+ u8 max_fifo_size;
+ u8 intr_trigger_level; /* interrupt trigger level */
+};
+
+/* State of each mdev device */
+struct mdev_state {
+ int irq_fd;
+ struct eventfd_ctx *intx_evtfd;
+ struct eventfd_ctx *msi_evtfd;
+ int irq_index;
+ u8 *vconfig;
+ struct mutex ops_lock;
+ struct mdev_device *mdev;
+ struct mdev_region_info region_info[VFIO_PCI_NUM_REGIONS];
+ u32 bar_mask[VFIO_PCI_NUM_REGIONS];
+ struct list_head next;
+ struct serial_port s[2];
+ struct mutex rxtx_lock;
+ struct vfio_device_info dev_info;
+ int nr_ports;
+};
+
+struct mutex mdev_list_lock;
+struct list_head mdev_devices_list;
+
+static const struct file_operations vd_fops = {
+ .owner = THIS_MODULE,
+};
+
+/* function prototypes */
+
+static int mtty_trigger_interrupt(uuid_le uuid);
+
+/* Helper functions */
+static struct mdev_state *find_mdev_state_by_uuid(uuid_le uuid)
+{
+ struct mdev_state *mds;
+
+ list_for_each_entry(mds, &mdev_devices_list, next) {
+ if (uuid_le_cmp(mds->mdev->uuid, uuid) == 0)
+ return mds;
+ }
+
+ return NULL;
+}
+
+void dump_buffer(char *buf, uint32_t count)
+{
+#if defined(DEBUG)
+ int i;
+
+ pr_info("Buffer:\n");
+ for (i = 0; i < count; i++) {
+ pr_info("%2x ", *(buf + i));
+ if ((i + 1) % 16 == 0)
+ pr_info("\n");
+ }
+#endif
+}
+
+static void mtty_create_config_space(struct mdev_state *mdev_state)
+{
+ /* PCI dev ID */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x0], 0x32534348);
+
+ /* Control: I/O+, Mem-, BusMaster- */
+ STORE_LE16((u16 *) &mdev_state->vconfig[0x4], 0x0001);
+
+ /* Status: capabilities list absent */
+ STORE_LE16((u16 *) &mdev_state->vconfig[0x6], 0x0200);
+
+ /* Rev ID */
+ mdev_state->vconfig[0x8] = 0x10;
+
+ /* programming interface class : 16550-compatible serial controller */
+ mdev_state->vconfig[0x9] = 0x02;
+
+ /* Sub class : 00 */
+ mdev_state->vconfig[0xa] = 0x00;
+
+ /* Base class : Simple Communication controllers */
+ mdev_state->vconfig[0xb] = 0x07;
+
+ /* base address registers */
+ /* BAR0: IO space */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x10], 0x000001);
+ mdev_state->bar_mask[0] = ~(MTTY_IO_BAR_SIZE) + 1;
+
+ if (mdev_state->nr_ports == 2) {
+ /* BAR1: IO space */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x14], 0x000001);
+ mdev_state->bar_mask[1] = ~(MTTY_IO_BAR_SIZE) + 1;
+ }
+
+ /* Subsystem ID */
+ STORE_LE32((u32 *) &mdev_state->vconfig[0x2c], 0x32534348);
+
+ mdev_state->vconfig[0x34] = 0x00; /* Cap Ptr */
+ mdev_state->vconfig[0x3d] = 0x01; /* interrupt pin (INTA#) */
+
+ /* Vendor specific data */
+ mdev_state->vconfig[0x40] = 0x23;
+ mdev_state->vconfig[0x43] = 0x80;
+ mdev_state->vconfig[0x44] = 0x23;
+ mdev_state->vconfig[0x48] = 0x23;
+ mdev_state->vconfig[0x4c] = 0x23;
+
+ mdev_state->vconfig[0x60] = 0x50;
+ mdev_state->vconfig[0x61] = 0x43;
+ mdev_state->vconfig[0x62] = 0x49;
+ mdev_state->vconfig[0x63] = 0x20;
+ mdev_state->vconfig[0x64] = 0x53;
+ mdev_state->vconfig[0x65] = 0x65;
+ mdev_state->vconfig[0x66] = 0x72;
+ mdev_state->vconfig[0x67] = 0x69;
+ mdev_state->vconfig[0x68] = 0x61;
+ mdev_state->vconfig[0x69] = 0x6c;
+ mdev_state->vconfig[0x6a] = 0x2f;
+ mdev_state->vconfig[0x6b] = 0x55;
+ mdev_state->vconfig[0x6c] = 0x41;
+ mdev_state->vconfig[0x6d] = 0x52;
+ mdev_state->vconfig[0x6e] = 0x54;
+}
+
+static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
+ char *buf, u32 count)
+{
+ u32 cfg_addr, bar_mask, bar_index = 0;
+
+ switch (offset) {
+ case 0x04: /* device control */
+ case 0x06: /* device status */
+ /* do nothing */
+ break;
+ case 0x3c: /* interrupt line */
+ mdev_state->vconfig[0x3c] = buf[0];
+ break;
+ case 0x3d:
+ /*
+ * Interrupt Pin is hardwired to INTA.
+ * This field is write protected by hardware
+ */
+ break;
+ case 0x10: /* BAR0 */
+ case 0x14: /* BAR1 */
+ if (offset == 0x10)
+ bar_index = 0;
+ else if (offset == 0x14)
+ bar_index = 1;
+
+ if ((mdev_state->nr_ports == 1) && (bar_index == 1)) {
+ STORE_LE32(&mdev_state->vconfig[offset], 0);
+ break;
+ }
+
+ cfg_addr = *(u32 *)buf;
+ pr_info("BAR%d addr 0x%x\n", bar_index, cfg_addr);
+
+ if (cfg_addr == 0xffffffff) {
+ bar_mask = mdev_state->bar_mask[bar_index];
+ cfg_addr = (cfg_addr & bar_mask);
+ }
+
+ cfg_addr |= (mdev_state->vconfig[offset] & 0x3ul);
+ STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
+ break;
+ case 0x18: /* BAR2 */
+ case 0x1c: /* BAR3 */
+ case 0x20: /* BAR4 */
+ STORE_LE32(&mdev_state->vconfig[offset], 0);
+ break;
+ default:
+ pr_info("PCI config write @0x%x of %d bytes not handled\n",
+ offset, count);
+ break;
+ }
+}
+
+static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
+ u16 offset, char *buf, u32 count)
+{
+ u8 data = *buf;
+
+ /* Handle data written by guest */
+ switch (offset) {
+ case UART_TX:
+ /* if DLAB set, data is LSB of divisor */
+ if (mdev_state->s[index].dlab) {
+ mdev_state->s[index].divisor |= data;
+ break;
+ }
+
+ mutex_lock(&mdev_state->rxtx_lock);
+
+ /* save in TX buffer */
+ if (mdev_state->s[index].rxtx.count <
+ mdev_state->s[index].max_fifo_size) {
+ mdev_state->s[index].rxtx.fifo[
+ mdev_state->s[index].rxtx.head] = data;
+ mdev_state->s[index].rxtx.count++;
+ CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.head);
+ mdev_state->s[index].overrun = false;
+
+ /*
+ * Trigger interrupt if receive data interrupt is
+ * enabled and fifo reached trigger level
+ */
+ if ((mdev_state->s[index].uart_reg[UART_IER] &
+ UART_IER_RDI) &&
+ (mdev_state->s[index].rxtx.count ==
+ mdev_state->s[index].intr_trigger_level)) {
+ /* trigger interrupt */
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: Fifo level trigger\n",
+ index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ } else {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: Buffer Overflow\n", index);
+#endif
+ mdev_state->s[index].overrun = true;
+
+ /*
+ * Trigger interrupt if receiver line status interrupt
+ * is enabled
+ */
+ if (mdev_state->s[index].uart_reg[UART_IER] &
+ UART_IER_RLSI)
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ mutex_unlock(&mdev_state->rxtx_lock);
+ break;
+
+ case UART_IER:
+ /* if DLAB set, data is MSB of divisor */
+ if (mdev_state->s[index].dlab)
+ mdev_state->s[index].divisor |= (u16)data << 8;
+ else {
+ mdev_state->s[index].uart_reg[offset] = data;
+ mutex_lock(&mdev_state->rxtx_lock);
+ if ((data & UART_IER_THRI) &&
+ (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail)) {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: IER_THRI write\n",
+ index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+
+ mutex_unlock(&mdev_state->rxtx_lock);
+ }
+
+ break;
+
+ case UART_FCR:
+ mdev_state->s[index].fcr = data;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ if (data & (UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT)) {
+ /* clear loop back FIFO */
+ mdev_state->s[index].rxtx.count = 0;
+ mdev_state->s[index].rxtx.head = 0;
+ mdev_state->s[index].rxtx.tail = 0;
+ }
+ mutex_unlock(&mdev_state->rxtx_lock);
+
+ switch (data & UART_FCR_TRIGGER_MASK) {
+ case UART_FCR_TRIGGER_1:
+ mdev_state->s[index].intr_trigger_level = 1;
+ break;
+
+ case UART_FCR_TRIGGER_4:
+ mdev_state->s[index].intr_trigger_level = 4;
+ break;
+
+ case UART_FCR_TRIGGER_8:
+ mdev_state->s[index].intr_trigger_level = 8;
+ break;
+
+ case UART_FCR_TRIGGER_14:
+ mdev_state->s[index].intr_trigger_level = 14;
+ break;
+ }
+
+ /*
+ * Set trigger level to 1 otherwise or implement timer with
+ * timeout of 4 characters and on expiring that timer set
+ * Recevice data timeout in IIR register
+ */
+ mdev_state->s[index].intr_trigger_level = 1;
+ if (data & UART_FCR_ENABLE_FIFO)
+ mdev_state->s[index].max_fifo_size = MAX_FIFO_SIZE;
+ else {
+ mdev_state->s[index].max_fifo_size = 1;
+ mdev_state->s[index].intr_trigger_level = 1;
+ }
+
+ break;
+
+ case UART_LCR:
+ if (data & UART_LCR_DLAB) {
+ mdev_state->s[index].dlab = true;
+ mdev_state->s[index].divisor = 0;
+ } else
+ mdev_state->s[index].dlab = false;
+
+ mdev_state->s[index].uart_reg[offset] = data;
+ break;
+
+ case UART_MCR:
+ mdev_state->s[index].uart_reg[offset] = data;
+
+ if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
+ (data & UART_MCR_OUT2)) {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: MCR_OUT2 write\n", index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+
+ if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
+ (data & (UART_MCR_RTS | UART_MCR_DTR))) {
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: MCR RTS/DTR write\n", index);
+#endif
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ break;
+
+ case UART_LSR:
+ case UART_MSR:
+ /* do nothing */
+ break;
+
+ case UART_SCR:
+ mdev_state->s[index].uart_reg[offset] = data;
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void handle_bar_read(unsigned int index, struct mdev_state *mdev_state,
+ u16 offset, char *buf, u32 count)
+{
+ /* Handle read requests by guest */
+ switch (offset) {
+ case UART_RX:
+ /* if DLAB set, data is LSB of divisor */
+ if (mdev_state->s[index].dlab) {
+ *buf = (u8)mdev_state->s[index].divisor;
+ break;
+ }
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* return data in tx buffer */
+ if (mdev_state->s[index].rxtx.head !=
+ mdev_state->s[index].rxtx.tail) {
+ *buf = mdev_state->s[index].rxtx.fifo[
+ mdev_state->s[index].rxtx.tail];
+ mdev_state->s[index].rxtx.count--;
+ CIRCULAR_BUF_INC_IDX(mdev_state->s[index].rxtx.tail);
+ }
+
+ if (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail) {
+ /*
+ * Trigger interrupt if tx buffer empty interrupt is
+ * enabled and fifo is empty
+ */
+#if defined(DEBUG_INTR)
+ pr_err("Serial port %d: Buffer Empty\n", index);
+#endif
+ if (mdev_state->s[index].uart_reg[UART_IER] &
+ UART_IER_THRI)
+ mtty_trigger_interrupt(mdev_state->mdev->uuid);
+ }
+ mutex_unlock(&mdev_state->rxtx_lock);
+
+ break;
+
+ case UART_IER:
+ if (mdev_state->s[index].dlab) {
+ *buf = (u8)(mdev_state->s[index].divisor >> 8);
+ break;
+ }
+ *buf = mdev_state->s[index].uart_reg[offset] & 0x0f;
+ break;
+
+ case UART_IIR:
+ {
+ u8 ier = mdev_state->s[index].uart_reg[UART_IER];
+ *buf = 0;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* Interrupt priority 1: Parity, overrun, framing or break */
+ if ((ier & UART_IER_RLSI) && mdev_state->s[index].overrun)
+ *buf |= UART_IIR_RLSI;
+
+ /* Interrupt priority 2: Fifo trigger level reached */
+ if ((ier & UART_IER_RDI) &&
+ (mdev_state->s[index].rxtx.count ==
+ mdev_state->s[index].intr_trigger_level))
+ *buf |= UART_IIR_RDI;
+
+ /* Interrupt priotiry 3: transmitter holding register empty */
+ if ((ier & UART_IER_THRI) &&
+ (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail))
+ *buf |= UART_IIR_THRI;
+
+ /* Interrupt priotiry 4: Modem status: CTS, DSR, RI or DCD */
+ if ((ier & UART_IER_MSI) &&
+ (mdev_state->s[index].uart_reg[UART_MCR] &
+ (UART_MCR_RTS | UART_MCR_DTR)))
+ *buf |= UART_IIR_MSI;
+
+ /* bit0: 0=> interrupt pending, 1=> no interrupt is pending */
+ if (*buf == 0)
+ *buf = UART_IIR_NO_INT;
+
+ /* set bit 6 & 7 to be 16550 compatible */
+ *buf |= 0xC0;
+ mutex_unlock(&mdev_state->rxtx_lock);
+ }
+ break;
+
+ case UART_LCR:
+ case UART_MCR:
+ *buf = mdev_state->s[index].uart_reg[offset];
+ break;
+
+ case UART_LSR:
+ {
+ u8 lsr = 0;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* atleast one char in FIFO */
+ if (mdev_state->s[index].rxtx.head !=
+ mdev_state->s[index].rxtx.tail)
+ lsr |= UART_LSR_DR;
+
+ /* if FIFO overrun */
+ if (mdev_state->s[index].overrun)
+ lsr |= UART_LSR_OE;
+
+ /* transmit FIFO empty and tramsitter empty */
+ if (mdev_state->s[index].rxtx.head ==
+ mdev_state->s[index].rxtx.tail)
+ lsr |= UART_LSR_TEMT | UART_LSR_THRE;
+
+ mutex_unlock(&mdev_state->rxtx_lock);
+ *buf = lsr;
+ break;
+ }
+ case UART_MSR:
+ *buf = UART_MSR_DSR | UART_MSR_DDSR | UART_MSR_DCD;
+
+ mutex_lock(&mdev_state->rxtx_lock);
+ /* if AFE is 1 and FIFO have space, set CTS bit */
+ if (mdev_state->s[index].uart_reg[UART_MCR] &
+ UART_MCR_AFE) {
+ if (mdev_state->s[index].rxtx.count <
+ mdev_state->s[index].max_fifo_size)
+ *buf |= UART_MSR_CTS | UART_MSR_DCTS;
+ } else
+ *buf |= UART_MSR_CTS | UART_MSR_DCTS;
+ mutex_unlock(&mdev_state->rxtx_lock);
+
+ break;
+
+ case UART_SCR:
+ *buf = mdev_state->s[index].uart_reg[offset];
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void mdev_read_base(struct mdev_state *mdev_state)
+{
+ int index, pos;
+ u32 start_lo, start_hi;
+ u32 mem_type;
+
+ pos = PCI_BASE_ADDRESS_0;
+
+ for (index = 0; index <= VFIO_PCI_BAR5_REGION_INDEX; index++) {
+
+ if (!mdev_state->region_info[index].size)
+ continue;
+
+ start_lo = (*(u32 *)(mdev_state->vconfig + pos)) &
+ PCI_BASE_ADDRESS_MEM_MASK;
+ mem_type = (*(u32 *)(mdev_state->vconfig + pos)) &
+ PCI_BASE_ADDRESS_MEM_TYPE_MASK;
+
+ switch (mem_type) {
+ case PCI_BASE_ADDRESS_MEM_TYPE_64:
+ start_hi = (*(u32 *)(mdev_state->vconfig + pos + 4));
+ pos += 4;
+ break;
+ case PCI_BASE_ADDRESS_MEM_TYPE_32:
+ case PCI_BASE_ADDRESS_MEM_TYPE_1M:
+ /* 1M mem BAR treated as 32-bit BAR */
+ default:
+ /* mem unknown type treated as 32-bit BAR */
+ start_hi = 0;
+ break;
+ }
+ pos += 4;
+ mdev_state->region_info[index].start = ((u64)start_hi << 32) |
+ start_lo;
+ }
+}
+
+static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
+ loff_t pos, bool is_write)
+{
+ struct mdev_state *mdev_state;
+ unsigned int index;
+ loff_t offset;
+ int ret = 0;
+
+ if (!mdev || !buf)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state) {
+ pr_err("%s mdev_state not found\n", __func__);
+ return -EINVAL;
+ }
+
+ mutex_lock(&mdev_state->ops_lock);
+
+ index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(pos);
+ offset = pos & MTTY_VFIO_PCI_OFFSET_MASK;
+ switch (index) {
+ case VFIO_PCI_CONFIG_REGION_INDEX:
+
+#if defined(DEBUG)
+ pr_info("%s: PCI config space %s at offset 0x%llx\n",
+ __func__, is_write ? "write" : "read", offset);
+#endif
+ if (is_write) {
+ dump_buffer(buf, count);
+ handle_pci_cfg_write(mdev_state, offset, buf, count);
+ } else {
+ memcpy(buf, (mdev_state->vconfig + offset), count);
+ dump_buffer(buf, count);
+ }
+
+ break;
+
+ case VFIO_PCI_BAR0_REGION_INDEX ... VFIO_PCI_BAR5_REGION_INDEX:
+ if (!mdev_state->region_info[index].start)
+ mdev_read_base(mdev_state);
+
+ if (is_write) {
+ dump_buffer(buf, count);
+
+#if defined(DEBUG_REGS)
+ pr_info("%s: BAR%d WR @0x%llx %s val:0x%02x dlab:%d\n",
+ __func__, index, offset, wr_reg[offset],
+ (u8)*buf, mdev_state->s[index].dlab);
+#endif
+ handle_bar_write(index, mdev_state, offset, buf, count);
+ } else {
+ handle_bar_read(index, mdev_state, offset, buf, count);
+ dump_buffer(buf, count);
+
+#if defined(DEBUG_REGS)
+ pr_info("%s: BAR%d RD @0x%llx %s val:0x%02x dlab:%d\n",
+ __func__, index, offset, rd_reg[offset],
+ (u8)*buf, mdev_state->s[index].dlab);
+#endif
+ }
+ break;
+
+ default:
+ ret = -1;
+ goto accessfailed;
+ }
+
+ ret = count;
+
+
+accessfailed:
+ mutex_unlock(&mdev_state->ops_lock);
+
+ return ret;
+}
+
+int mtty_create(struct kobject *kobj, struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state;
+ char name[MTTY_STRING_LEN];
+ int nr_ports = 0, i;
+
+ if (!mdev)
+ return -EINVAL;
+
+ for (i = 0; i < 2; i++) {
+ snprintf(name, MTTY_STRING_LEN, "%s-%d",
+ dev_driver_string(mdev->parent->dev), i + 1);
+ if (!strcmp(kobj->name, name)) {
+ nr_ports = i + 1;
+ break;
+ }
+ }
+
+ if (!nr_ports)
+ return -EINVAL;
+
+ mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
+ if (mdev_state == NULL)
+ return -ENOMEM;
+
+ mdev_state->nr_ports = nr_ports;
+ mdev_state->irq_index = -1;
+ mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
+ mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
+ mutex_init(&mdev_state->rxtx_lock);
+ mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
+
+ if (mdev_state->vconfig == NULL) {
+ kfree(mdev_state);
+ return -ENOMEM;
+ }
+
+ mutex_init(&mdev_state->ops_lock);
+ mdev_state->mdev = mdev;
+ mdev_set_drvdata(mdev, mdev_state);
+
+ mtty_create_config_space(mdev_state);
+
+ mutex_lock(&mdev_list_lock);
+ list_add(&mdev_state->next, &mdev_devices_list);
+ mutex_unlock(&mdev_list_lock);
+
+ return 0;
+}
+
+int mtty_remove(struct mdev_device *mdev)
+{
+ struct mdev_state *mds, *tmp_mds;
+ struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ int ret = -EINVAL;
+
+ mutex_lock(&mdev_list_lock);
+ list_for_each_entry_safe(mds, tmp_mds, &mdev_devices_list, next) {
+ if (mdev_state == mds) {
+ list_del(&mdev_state->next);
+ mdev_set_drvdata(mdev, NULL);
+ kfree(mdev_state->vconfig);
+ kfree(mdev_state);
+ ret = 0;
+ break;
+ }
+ }
+ mutex_unlock(&mdev_list_lock);
+
+ return ret;
+}
+
+int mtty_reset(struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -EINVAL;
+
+ pr_info("%s: called\n", __func__);
+
+ return 0;
+}
+
+ssize_t mtty_read(struct mdev_device *mdev, char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ unsigned int done = 0;
+ int ret;
+
+ while (count) {
+ size_t filled;
+
+ if (count >= 4 && !(*ppos % 4)) {
+ u32 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 4;
+ } else if (count >= 2 && !(*ppos % 2)) {
+ u16 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 2;
+ } else {
+ u8 val;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, false);
+ if (ret <= 0)
+ goto read_err;
+
+ if (copy_to_user(buf, &val, sizeof(val)))
+ goto read_err;
+
+ filled = 1;
+ }
+
+ count -= filled;
+ done += filled;
+ *ppos += filled;
+ buf += filled;
+ }
+
+ return done;
+
+read_err:
+ return -EFAULT;
+}
+
+ssize_t mtty_write(struct mdev_device *mdev, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ unsigned int done = 0;
+ int ret;
+
+ while (count) {
+ size_t filled;
+
+ if (count >= 4 && !(*ppos % 4)) {
+ u32 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 4;
+ } else if (count >= 2 && !(*ppos % 2)) {
+ u16 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 2;
+ } else {
+ u8 val;
+
+ if (copy_from_user(&val, buf, sizeof(val)))
+ goto write_err;
+
+ ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ *ppos, true);
+ if (ret <= 0)
+ goto write_err;
+
+ filled = 1;
+ }
+ count -= filled;
+ done += filled;
+ *ppos += filled;
+ buf += filled;
+ }
+
+ return done;
+write_err:
+ return -EFAULT;
+}
+
+static int mtty_set_irqs(struct mdev_device *mdev, uint32_t flags,
+ unsigned int index, unsigned int start,
+ unsigned int count, void *data)
+{
+ int ret = 0;
+ struct mdev_state *mdev_state;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -EINVAL;
+
+ mutex_lock(&mdev_state->ops_lock);
+ switch (index) {
+ case VFIO_PCI_INTX_IRQ_INDEX:
+ switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+ case VFIO_IRQ_SET_ACTION_MASK:
+ case VFIO_IRQ_SET_ACTION_UNMASK:
+ break;
+ case VFIO_IRQ_SET_ACTION_TRIGGER:
+ {
+ if (flags & VFIO_IRQ_SET_DATA_NONE) {
+ pr_info("%s: disable INTx\n", __func__);
+ if (mdev_state->intx_evtfd)
+ eventfd_ctx_put(mdev_state->intx_evtfd);
+ break;
+ }
+
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ int fd = *(int *)data;
+
+ if (fd > 0) {
+ struct eventfd_ctx *evt;
+
+ evt = eventfd_ctx_fdget(fd);
+ if (IS_ERR(evt)) {
+ ret = PTR_ERR(evt);
+ break;
+ }
+ mdev_state->intx_evtfd = evt;
+ mdev_state->irq_fd = fd;
+ mdev_state->irq_index = index;
+ break;
+ }
+ }
+ break;
+ }
+ }
+ break;
+ case VFIO_PCI_MSI_IRQ_INDEX:
+ switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+ case VFIO_IRQ_SET_ACTION_MASK:
+ case VFIO_IRQ_SET_ACTION_UNMASK:
+ break;
+ case VFIO_IRQ_SET_ACTION_TRIGGER:
+ if (flags & VFIO_IRQ_SET_DATA_NONE) {
+ if (mdev_state->msi_evtfd)
+ eventfd_ctx_put(mdev_state->msi_evtfd);
+ pr_info("%s: disable MSI\n", __func__);
+ mdev_state->irq_index = VFIO_PCI_INTX_IRQ_INDEX;
+ break;
+ }
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ int fd = *(int *)data;
+ struct eventfd_ctx *evt;
+
+ if (fd <= 0)
+ break;
+
+ if (mdev_state->msi_evtfd)
+ break;
+
+ evt = eventfd_ctx_fdget(fd);
+ if (IS_ERR(evt)) {
+ ret = PTR_ERR(evt);
+ break;
+ }
+ mdev_state->msi_evtfd = evt;
+ mdev_state->irq_fd = fd;
+ mdev_state->irq_index = index;
+ }
+ break;
+ }
+ break;
+ case VFIO_PCI_MSIX_IRQ_INDEX:
+ pr_info("%s: MSIX_IRQ\n", __func__);
+ break;
+ case VFIO_PCI_ERR_IRQ_INDEX:
+ pr_info("%s: ERR_IRQ\n", __func__);
+ break;
+ case VFIO_PCI_REQ_IRQ_INDEX:
+ pr_info("%s: REQ_IRQ\n", __func__);
+ break;
+ }
+
+ mutex_unlock(&mdev_state->ops_lock);
+ return ret;
+}
+
+static int mtty_trigger_interrupt(uuid_le uuid)
+{
+ int ret = -1;
+ struct mdev_state *mdev_state;
+
+ mdev_state = find_mdev_state_by_uuid(uuid);
+
+ if (!mdev_state) {
+ pr_info("%s: mdev not found\n", __func__);
+ return -EINVAL;
+ }
+
+ if ((mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX) &&
+ (!mdev_state->msi_evtfd))
+ return -EINVAL;
+ else if ((mdev_state->irq_index == VFIO_PCI_INTX_IRQ_INDEX) &&
+ (!mdev_state->intx_evtfd)) {
+ pr_info("%s: Intr eventfd not found\n", __func__);
+ return -EINVAL;
+ }
+
+ if (mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX)
+ ret = eventfd_signal(mdev_state->msi_evtfd, 1);
+ else
+ ret = eventfd_signal(mdev_state->intx_evtfd, 1);
+
+#if defined(DEBUG_INTR)
+ pr_info("Intx triggered\n");
+#endif
+ if (ret != 1)
+ pr_err("%s: eventfd signal failed (%d)\n", __func__, ret);
+
+ return ret;
+}
+
+int mtty_get_region_info(struct mdev_device *mdev,
+ struct vfio_region_info *region_info,
+ u16 *cap_type_id, void **cap_type)
+{
+ unsigned int size = 0;
+ struct mdev_state *mdev_state;
+ int bar_index;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -EINVAL;
+
+ mutex_lock(&mdev_state->ops_lock);
+ bar_index = region_info->index;
+
+ switch (bar_index) {
+ case VFIO_PCI_CONFIG_REGION_INDEX:
+ size = MTTY_CONFIG_SPACE_SIZE;
+ break;
+ case VFIO_PCI_BAR0_REGION_INDEX:
+ size = MTTY_IO_BAR_SIZE;
+ break;
+ case VFIO_PCI_BAR1_REGION_INDEX:
+ if (mdev_state->nr_ports == 2)
+ size = MTTY_IO_BAR_SIZE;
+ break;
+ default:
+ size = 0;
+ break;
+ }
+
+ mdev_state->region_info[bar_index].size = size;
+ mdev_state->region_info[bar_index].vfio_offset =
+ MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
+
+ region_info->size = size;
+ region_info->offset = MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
+ region_info->flags = VFIO_REGION_INFO_FLAG_READ |
+ VFIO_REGION_INFO_FLAG_WRITE;
+ mutex_unlock(&mdev_state->ops_lock);
+ return 0;
+}
+
+int mtty_get_irq_info(struct mdev_device *mdev, struct vfio_irq_info *irq_info)
+{
+ switch (irq_info->index) {
+ case VFIO_PCI_INTX_IRQ_INDEX:
+ case VFIO_PCI_MSI_IRQ_INDEX:
+ case VFIO_PCI_REQ_IRQ_INDEX:
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ irq_info->flags = VFIO_IRQ_INFO_EVENTFD;
+ irq_info->count = 1;
+
+ if (irq_info->index == VFIO_PCI_INTX_IRQ_INDEX)
+ irq_info->flags |= (VFIO_IRQ_INFO_MASKABLE |
+ VFIO_IRQ_INFO_AUTOMASKED);
+ else
+ irq_info->flags |= VFIO_IRQ_INFO_NORESIZE;
+
+ return 0;
+}
+
+int mtty_get_device_info(struct mdev_device *mdev,
+ struct vfio_device_info *dev_info)
+{
+ dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
+ dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
+ dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
+
+ return 0;
+}
+
+static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret = 0;
+ unsigned long minsz;
+ struct mdev_state *mdev_state;
+
+ if (!mdev)
+ return -EINVAL;
+
+ mdev_state = mdev_get_drvdata(mdev);
+ if (!mdev_state)
+ return -ENODEV;
+
+ switch (cmd) {
+ case VFIO_DEVICE_GET_INFO:
+ {
+ struct vfio_device_info info;
+
+ minsz = offsetofend(struct vfio_device_info, num_irqs);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ ret = mtty_get_device_info(mdev, &info);
+ if (ret)
+ return ret;
+
+ memcpy(&mdev_state->dev_info, &info, sizeof(info));
+
+ return copy_to_user((void __user *)arg, &info, minsz);
+ }
+ case VFIO_DEVICE_GET_REGION_INFO:
+ {
+ struct vfio_region_info info;
+ u16 cap_type_id = 0;
+ void *cap_type = NULL;
+
+ minsz = offsetofend(struct vfio_region_info, offset);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ ret = mtty_get_region_info(mdev, &info, &cap_type_id,
+ &cap_type);
+ if (ret)
+ return ret;
+
+ return copy_to_user((void __user *)arg, &info, minsz);
+ }
+
+ case VFIO_DEVICE_GET_IRQ_INFO:
+ {
+ struct vfio_irq_info info;
+
+ minsz = offsetofend(struct vfio_irq_info, count);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if ((info.argsz < minsz) ||
+ (info.index >= mdev_state->dev_info.num_irqs))
+ return -EINVAL;
+
+ ret = mtty_get_irq_info(mdev, &info);
+ if (ret)
+ return ret;
+
+ if (info.count == -1)
+ return -EINVAL;
+
+ return copy_to_user((void __user *)arg, &info, minsz);
+ }
+ case VFIO_DEVICE_SET_IRQS:
+ {
+ struct vfio_irq_set hdr;
+ u8 *data = NULL, *ptr = NULL;
+ size_t data_size = 0;
+
+ minsz = offsetofend(struct vfio_irq_set, count);
+
+ if (copy_from_user(&hdr, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ ret = vfio_set_irqs_validate_and_prepare(&hdr,
+ mdev_state->dev_info.num_irqs,
+ VFIO_PCI_NUM_IRQS,
+ &data_size);
+ if (ret)
+ return ret;
+
+ if (data_size) {
+ ptr = data = memdup_user((void __user *)(arg + minsz),
+ data_size);
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+ }
+
+ ret = mtty_set_irqs(mdev, hdr.flags, hdr.index, hdr.start,
+ hdr.count, data);
+
+ kfree(ptr);
+ return ret;
+ }
+ case VFIO_DEVICE_RESET:
+ return mtty_reset(mdev);
+ }
+ return -ENOTTY;
+}
+
+int mtty_open(struct mdev_device *mdev)
+{
+ pr_info("%s\n", __func__);
+ return 0;
+}
+
+void mtty_close(struct mdev_device *mdev)
+{
+ pr_info("%s\n", __func__);
+}
+
+static ssize_t
+sample_mtty_dev_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "This is phy device\n");
+}
+
+static DEVICE_ATTR_RO(sample_mtty_dev);
+
+static struct attribute *mtty_dev_attrs[] = {
+ &dev_attr_sample_mtty_dev.attr,
+ NULL,
+};
+
+static const struct attribute_group mtty_dev_group = {
+ .name = "mtty_dev",
+ .attrs = mtty_dev_attrs,
+};
+
+const struct attribute_group *mtty_dev_groups[] = {
+ &mtty_dev_group,
+ NULL,
+};
+
+static ssize_t
+sample_mdev_dev_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct mdev_device *mdev = to_mdev_device(dev);
+
+ if (mdev)
+ return sprintf(buf, "This is MDEV %s\n", dev_name(&mdev->dev));
+
+ return sprintf(buf, "\n");
+}
+
+static DEVICE_ATTR_RO(sample_mdev_dev);
+
+static struct attribute *mdev_dev_attrs[] = {
+ &dev_attr_sample_mdev_dev.attr,
+ NULL,
+};
+
+static const struct attribute_group mdev_dev_group = {
+ .name = "vendor",
+ .attrs = mdev_dev_attrs,
+};
+
+const struct attribute_group *mdev_dev_groups[] = {
+ &mdev_dev_group,
+ NULL,
+};
+
+static ssize_t
+name_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+ char name[MTTY_STRING_LEN];
+ int i;
+ const char *name_str[2] = {"Single port serial", "Dual port serial"};
+
+ for (i = 0; i < 2; i++) {
+ snprintf(name, MTTY_STRING_LEN, "%s-%d",
+ dev_driver_string(dev), i + 1);
+ if (!strcmp(kobj->name, name))
+ return sprintf(buf, "%s\n", name_str[i]);
+ }
+
+ return -EINVAL;
+}
+
+MDEV_TYPE_ATTR_RO(name);
+
+static ssize_t
+available_instances_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+ char name[MTTY_STRING_LEN];
+ int i;
+ struct mdev_state *mds;
+ int ports = 0, used = 0;
+
+ for (i = 0; i < 2; i++) {
+ snprintf(name, MTTY_STRING_LEN, "%s-%d",
+ dev_driver_string(dev), i + 1);
+ if (!strcmp(kobj->name, name)) {
+ ports = i + 1;
+ break;
+ }
+ }
+
+ if (!ports)
+ return -EINVAL;
+
+ list_for_each_entry(mds, &mdev_devices_list, next)
+ used += mds->nr_ports;
+
+ return sprintf(buf, "%d\n", (MAX_MTTYS - used)/ports);
+}
+
+MDEV_TYPE_ATTR_RO(available_instances);
+
+
+static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
+ char *buf)
+{
+ return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
+}
+
+MDEV_TYPE_ATTR_RO(device_api);
+
+static struct attribute *mdev_types_attrs[] = {
+ &mdev_type_attr_name.attr,
+ &mdev_type_attr_device_api.attr,
+ &mdev_type_attr_available_instances.attr,
+ NULL,
+};
+
+static struct attribute_group mdev_type_group1 = {
+ .name = "1",
+ .attrs = mdev_types_attrs,
+};
+
+static struct attribute_group mdev_type_group2 = {
+ .name = "2",
+ .attrs = mdev_types_attrs,
+};
+
+struct attribute_group *mdev_type_groups[] = {
+ &mdev_type_group1,
+ &mdev_type_group2,
+ NULL,
+};
+
+struct parent_ops mdev_fops = {
+ .owner = THIS_MODULE,
+ .dev_attr_groups = mtty_dev_groups,
+ .mdev_attr_groups = mdev_dev_groups,
+ .supported_type_groups = mdev_type_groups,
+ .create = mtty_create,
+ .remove = mtty_remove,
+ .open = mtty_open,
+ .release = mtty_close,
+ .read = mtty_read,
+ .write = mtty_write,
+ .ioctl = mtty_ioctl,
+};
+
+static void mtty_device_release(struct device *dev)
+{
+ dev_dbg(dev, "mtty: released\n");
+}
+
+static int __init mtty_dev_init(void)
+{
+ int ret = 0;
+
+ pr_info("mtty_dev: %s\n", __func__);
+
+ memset(&mtty_dev, 0, sizeof(mtty_dev));
+
+ idr_init(&mtty_dev.vd_idr);
+
+ ret = alloc_chrdev_region(&mtty_dev.vd_devt, 0, MINORMASK, MTTY_NAME);
+
+ if (ret < 0) {
+ pr_err("Error: failed to register mtty_dev, err:%d\n", ret);
+ return ret;
+ }
+
+ cdev_init(&mtty_dev.vd_cdev, &vd_fops);
+ cdev_add(&mtty_dev.vd_cdev, mtty_dev.vd_devt, MINORMASK);
+
+ pr_info("major_number:%d\n", MAJOR(mtty_dev.vd_devt));
+
+ mtty_dev.vd_class = class_create(THIS_MODULE, MTTY_CLASS_NAME);
+
+ if (IS_ERR(mtty_dev.vd_class)) {
+ pr_err("Error: failed to register mtty_dev class\n");
+ goto failed1;
+ }
+
+ mtty_dev.dev.class = mtty_dev.vd_class;
+ mtty_dev.dev.release = mtty_device_release;
+ dev_set_name(&mtty_dev.dev, "%s", MTTY_NAME);
+
+ ret = device_register(&mtty_dev.dev);
+ if (ret)
+ goto failed2;
+
+ if (mdev_register_device(&mtty_dev.dev, &mdev_fops) != 0)
+ goto failed3;
+
+ mutex_init(&mdev_list_lock);
+ INIT_LIST_HEAD(&mdev_devices_list);
+
+ goto all_done;
+
+failed3:
+
+ device_unregister(&mtty_dev.dev);
+failed2:
+ class_destroy(mtty_dev.vd_class);
+
+failed1:
+ cdev_del(&mtty_dev.vd_cdev);
+ unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
+
+all_done:
+ return ret;
+}
+
+static void __exit mtty_dev_exit(void)
+{
+ mtty_dev.dev.bus = NULL;
+ mdev_unregister_device(&mtty_dev.dev);
+
+ device_unregister(&mtty_dev.dev);
+ idr_destroy(&mtty_dev.vd_idr);
+ cdev_del(&mtty_dev.vd_cdev);
+ unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
+ class_destroy(mtty_dev.vd_class);
+ mtty_dev.vd_class = NULL;
+ pr_info("mtty_dev: Unloaded!\n");
+}
+
+module_init(mtty_dev_init)
+module_exit(mtty_dev_exit)
+
+MODULE_LICENSE("GPL");
+MODULE_INFO(supported, "Test driver that simulate serial port over PCI");
+MODULE_VERSION(VERSION_STRING);
+MODULE_AUTHOR(DRIVER_AUTHOR);
diff --git a/Documentation/vfio-mdev/vfio-mediated-device.txt b/Documentation/vfio-mdev/vfio-mediated-device.txt
index 69660aff86e3..9b4728436dc4 100644
--- a/Documentation/vfio-mdev/vfio-mediated-device.txt
+++ b/Documentation/vfio-mdev/vfio-mediated-device.txt
@@ -288,8 +288,109 @@ these callbacks are supported in the TYPE1 IOMMU module. To enable them for
other IOMMU backend modules, such as PPC64 sPAPR module, they need to provide
these two callback functions.
+Using the Sample Code
+=====================
+
+mtty.c in this folder is a sample driver program to demonstrate how to use the
+mediated device framework.
+
+The sample driver creates an mdev device that simulates a serial port over a PCI
+card.
+
+1. Build and load the mtty.ko module.
+
+ This step creates a dummy device, /sys/devices/virtual/mtty/mtty/
+
+ Files in this device directory in sysfs are similar to the following:
+
+ # tree /sys/devices/virtual/mtty/mtty/
+ /sys/devices/virtual/mtty/mtty/
+ |-- mdev_supported_types
+ | |-- mtty-1
+ | | |-- available_instances
+ | | |-- create
+ | | |-- device_api
+ | | |-- devices
+ | | `-- name
+ | `-- mtty-2
+ | |-- available_instances
+ | |-- create
+ | |-- device_api
+ | |-- devices
+ | `-- name
+ |-- mtty_dev
+ | `-- sample_mtty_dev
+ |-- power
+ | |-- autosuspend_delay_ms
+ | |-- control
+ | |-- runtime_active_time
+ | |-- runtime_status
+ | `-- runtime_suspended_time
+ |-- subsystem -> ../../../../class/mtty
+ `-- uevent
+
+2. Create a mediated device by using the dummy device that you created in the
+ previous step.
+
+ # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > \
+ /sys/devices/virtual/mtty/mtty/mdev_supported_types/mtty-2/create
+
+3. Add parameters to qemu-kvm.
+
+ -device vfio-pci,\
+ sysfsdev=/sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001
+
+4. Boot the VM.
+
+ In the Linux guest VM, with no hardware on the host, the device appears
+ as follows:
+
+ # lspci -s 00:05.0 -xxvv
+ 00:05.0 Serial controller: Device 4348:3253 (rev 10) (prog-if 02 [16550])
+ Subsystem: Device 4348:3253
+ Physical Slot: 5
+ Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr-
+ Stepping- SERR- FastB2B- DisINTx-
+ Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort-
+ <TAbort- <MAbort- >SERR- <PERR- INTx-
+ Interrupt: pin A routed to IRQ 10
+ Region 0: I/O ports at c150 [size=8]
+ Region 1: I/O ports at c158 [size=8]
+ Kernel driver in use: serial
+ 00: 48 43 53 32 01 00 00 02 10 02 00 07 00 00 00 00
+ 10: 51 c1 00 00 59 c1 00 00 00 00 00 00 00 00 00 00
+ 20: 00 00 00 00 00 00 00 00 00 00 00 00 48 43 53 32
+ 30: 00 00 00 00 00 00 00 00 00 00 00 00 0a 01 00 00
+
+ In the Linux guest VM, dmesg output for the device is as follows:
+
+ serial 0000:00:05.0: PCI INT A -> Link[LNKA] -> GSI 10 (level, high) -> IRQ
+10
+ 0000:00:05.0: ttyS1 at I/O 0xc150 (irq = 10) is a 16550A
+ 0000:00:05.0: ttyS2 at I/O 0xc158 (irq = 10) is a 16550A
+
+
+5. In the Linux guest VM, check the serial ports.
+
+ # setserial -g /dev/ttyS*
+ /dev/ttyS0, UART: 16550A, Port: 0x03f8, IRQ: 4
+ /dev/ttyS1, UART: 16550A, Port: 0xc150, IRQ: 10
+ /dev/ttyS2, UART: 16550A, Port: 0xc158, IRQ: 10
+
+6. Using a minicom or any terminal enulation program, open port /dev/ttyS1 or
+ /dev/ttyS2 with hardware flow control disabled.
+
+7. Type data on the minicom terminal or send data to the terminal emulation
+ program and read the data.
+
+ Data is loop backed from hosts mtty driver.
+
+8. Destroy the mediated device that you created.
+
+ # echo 1 > /sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001/remove
+
References
-----------
+==========
[1] See Documentation/vfio.txt for more information on VFIO.
[2] struct mdev_driver in include/linux/mdev.h
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* Re: [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
(?)
@ 2016-10-27 12:11 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-27 12:11 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
> argument.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
> ---
> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
> 1 file changed, 18 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 72fee415044a..3d916b965492 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
> return 0;
> }
>
> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
> + int prot, unsigned long *pfn)
> {
> struct page *page[1];
> struct vm_area_struct *vma;
> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
> int ret = -EFAULT;
>
> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
> + if (remote_mm) {
> + down_read(&mm->mmap_sem);
> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
> + !!(prot & IOMMU_WRITE), 0, page, NULL);
Hi Kirti,
It seems that get_user_pages_remote has only 7 args but you somehow gives 8
here?
--
Thanks,
Jike
> + up_read(&mm->mmap_sem);
> + } else
> + ret = get_user_pages_fast(vaddr, 1,
> + !!(prot & IOMMU_WRITE), page);
> +
> + if (ret == 1) {
> *pfn = page_to_pfn(page[0]);
> return 0;
> }
>
> - down_read(¤t->mm->mmap_sem);
> + down_read(&mm->mmap_sem);
>
> - vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
> + vma = find_vma_intersection(mm, vaddr, vaddr + 1);
>
> if (vma && vma->vm_flags & VM_PFNMAP) {
> *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
> @@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
> ret = 0;
> }
>
> - up_read(¤t->mm->mmap_sem);
> + up_read(&mm->mmap_sem);
>
> return ret;
> }
> @@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> if (!current->mm)
> return -ENODEV;
>
> - ret = vaddr_get_pfn(vaddr, prot, pfn_base);
> + ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
> if (ret)
> return ret;
>
> @@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
> unsigned long pfn = 0;
>
> - ret = vaddr_get_pfn(vaddr, prot, &pfn);
> + ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
> if (ret)
> break;
>
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
@ 2016-10-27 12:11 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-27 12:11 UTC (permalink / raw)
To: Kirti Wankhede
Cc: kevin.tian, cjia, kvm, qemu-devel, linux-kernel, alex.williamson,
kraxel, pbonzini, bjsdjshi
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
> argument.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
> ---
> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
> 1 file changed, 18 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 72fee415044a..3d916b965492 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
> return 0;
> }
>
> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
> + int prot, unsigned long *pfn)
> {
> struct page *page[1];
> struct vm_area_struct *vma;
> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
> int ret = -EFAULT;
>
> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
> + if (remote_mm) {
> + down_read(&mm->mmap_sem);
> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
> + !!(prot & IOMMU_WRITE), 0, page, NULL);
Hi Kirti,
It seems that get_user_pages_remote has only 7 args but you somehow gives 8
here?
--
Thanks,
Jike
> + up_read(&mm->mmap_sem);
> + } else
> + ret = get_user_pages_fast(vaddr, 1,
> + !!(prot & IOMMU_WRITE), page);
> +
> + if (ret == 1) {
> *pfn = page_to_pfn(page[0]);
> return 0;
> }
>
> - down_read(¤t->mm->mmap_sem);
> + down_read(&mm->mmap_sem);
>
> - vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
> + vma = find_vma_intersection(mm, vaddr, vaddr + 1);
>
> if (vma && vma->vm_flags & VM_PFNMAP) {
> *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
> @@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
> ret = 0;
> }
>
> - up_read(¤t->mm->mmap_sem);
> + up_read(&mm->mmap_sem);
>
> return ret;
> }
> @@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> if (!current->mm)
> return -ENODEV;
>
> - ret = vaddr_get_pfn(vaddr, prot, pfn_base);
> + ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
> if (ret)
> return ret;
>
> @@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
> unsigned long pfn = 0;
>
> - ret = vaddr_get_pfn(vaddr, prot, &pfn);
> + ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
> if (ret)
> break;
>
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
@ 2016-10-27 12:11 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-27 12:11 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
> argument.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
> ---
> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
> 1 file changed, 18 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 72fee415044a..3d916b965492 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
> return 0;
> }
>
> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
> + int prot, unsigned long *pfn)
> {
> struct page *page[1];
> struct vm_area_struct *vma;
> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
> int ret = -EFAULT;
>
> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
> + if (remote_mm) {
> + down_read(&mm->mmap_sem);
> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
> + !!(prot & IOMMU_WRITE), 0, page, NULL);
Hi Kirti,
It seems that get_user_pages_remote has only 7 args but you somehow gives 8
here?
--
Thanks,
Jike
> + up_read(&mm->mmap_sem);
> + } else
> + ret = get_user_pages_fast(vaddr, 1,
> + !!(prot & IOMMU_WRITE), page);
> +
> + if (ret == 1) {
> *pfn = page_to_pfn(page[0]);
> return 0;
> }
>
> - down_read(¤t->mm->mmap_sem);
> + down_read(&mm->mmap_sem);
>
> - vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
> + vma = find_vma_intersection(mm, vaddr, vaddr + 1);
>
> if (vma && vma->vm_flags & VM_PFNMAP) {
> *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
> @@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
> ret = 0;
> }
>
> - up_read(¤t->mm->mmap_sem);
> + up_read(&mm->mmap_sem);
>
> return ret;
> }
> @@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> if (!current->mm)
> return -ENODEV;
>
> - ret = vaddr_get_pfn(vaddr, prot, pfn_base);
> + ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
> if (ret)
> return ret;
>
> @@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
> unsigned long pfn = 0;
>
> - ret = vaddr_get_pfn(vaddr, prot, &pfn);
> + ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
> if (ret)
> break;
>
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
2016-10-27 12:11 ` Jike Song
(?)
@ 2016-10-27 12:24 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-27 12:24 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 5:41 PM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
>> argument.
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
>> ---
>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>> index 72fee415044a..3d916b965492 100644
>> --- a/drivers/vfio/vfio_iommu_type1.c
>> +++ b/drivers/vfio/vfio_iommu_type1.c
>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
>> return 0;
>> }
>>
>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
>> + int prot, unsigned long *pfn)
>> {
>> struct page *page[1];
>> struct vm_area_struct *vma;
>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
>> int ret = -EFAULT;
>>
>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
>> + if (remote_mm) {
>> + down_read(&mm->mmap_sem);
>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
>> + !!(prot & IOMMU_WRITE), 0, page, NULL);
>
> Hi Kirti,
>
> It seems that get_user_pages_remote has only 7 args but you somehow gives 8
> here?
>
I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c:
long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
int write, int force, struct page **pages,
struct vm_area_struct **vmas)
{
return __get_user_pages_locked(tsk, mm, start, nr_pages, write,
force,
pages, vmas, NULL, false,
FOLL_TOUCH | FOLL_REMOTE);
}
EXPORT_SYMBOL(get_user_pages_remote);
Thanks,
Kirti
> --
> Thanks,
> Jike
>
>> + up_read(&mm->mmap_sem);
>> + } else
>> + ret = get_user_pages_fast(vaddr, 1,
>> + !!(prot & IOMMU_WRITE), page);
>> +
>> + if (ret == 1) {
>> *pfn = page_to_pfn(page[0]);
>> return 0;
>> }
>>
>> - down_read(¤t->mm->mmap_sem);
>> + down_read(&mm->mmap_sem);
>>
>> - vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
>> + vma = find_vma_intersection(mm, vaddr, vaddr + 1);
>>
>> if (vma && vma->vm_flags & VM_PFNMAP) {
>> *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
>> @@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>> ret = 0;
>> }
>>
>> - up_read(¤t->mm->mmap_sem);
>> + up_read(&mm->mmap_sem);
>>
>> return ret;
>> }
>> @@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
>> if (!current->mm)
>> return -ENODEV;
>>
>> - ret = vaddr_get_pfn(vaddr, prot, pfn_base);
>> + ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
>> if (ret)
>> return ret;
>>
>> @@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
>> for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
>> unsigned long pfn = 0;
>>
>> - ret = vaddr_get_pfn(vaddr, prot, &pfn);
>> + ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
>> if (ret)
>> break;
>>
>>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
@ 2016-10-27 12:24 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-27 12:24 UTC (permalink / raw)
To: Jike Song
Cc: kevin.tian, cjia, kvm, qemu-devel, linux-kernel, alex.williamson,
kraxel, pbonzini, bjsdjshi
On 10/27/2016 5:41 PM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
>> argument.
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
>> ---
>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>> index 72fee415044a..3d916b965492 100644
>> --- a/drivers/vfio/vfio_iommu_type1.c
>> +++ b/drivers/vfio/vfio_iommu_type1.c
>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
>> return 0;
>> }
>>
>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
>> + int prot, unsigned long *pfn)
>> {
>> struct page *page[1];
>> struct vm_area_struct *vma;
>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
>> int ret = -EFAULT;
>>
>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
>> + if (remote_mm) {
>> + down_read(&mm->mmap_sem);
>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
>> + !!(prot & IOMMU_WRITE), 0, page, NULL);
>
> Hi Kirti,
>
> It seems that get_user_pages_remote has only 7 args but you somehow gives 8
> here?
>
I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c:
long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
int write, int force, struct page **pages,
struct vm_area_struct **vmas)
{
return __get_user_pages_locked(tsk, mm, start, nr_pages, write,
force,
pages, vmas, NULL, false,
FOLL_TOUCH | FOLL_REMOTE);
}
EXPORT_SYMBOL(get_user_pages_remote);
Thanks,
Kirti
> --
> Thanks,
> Jike
>
>> + up_read(&mm->mmap_sem);
>> + } else
>> + ret = get_user_pages_fast(vaddr, 1,
>> + !!(prot & IOMMU_WRITE), page);
>> +
>> + if (ret == 1) {
>> *pfn = page_to_pfn(page[0]);
>> return 0;
>> }
>>
>> - down_read(¤t->mm->mmap_sem);
>> + down_read(&mm->mmap_sem);
>>
>> - vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
>> + vma = find_vma_intersection(mm, vaddr, vaddr + 1);
>>
>> if (vma && vma->vm_flags & VM_PFNMAP) {
>> *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
>> @@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>> ret = 0;
>> }
>>
>> - up_read(¤t->mm->mmap_sem);
>> + up_read(&mm->mmap_sem);
>>
>> return ret;
>> }
>> @@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
>> if (!current->mm)
>> return -ENODEV;
>>
>> - ret = vaddr_get_pfn(vaddr, prot, pfn_base);
>> + ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
>> if (ret)
>> return ret;
>>
>> @@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
>> for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
>> unsigned long pfn = 0;
>>
>> - ret = vaddr_get_pfn(vaddr, prot, &pfn);
>> + ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
>> if (ret)
>> break;
>>
>>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
@ 2016-10-27 12:24 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-27 12:24 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 5:41 PM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
>> argument.
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
>> ---
>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>> index 72fee415044a..3d916b965492 100644
>> --- a/drivers/vfio/vfio_iommu_type1.c
>> +++ b/drivers/vfio/vfio_iommu_type1.c
>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
>> return 0;
>> }
>>
>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
>> + int prot, unsigned long *pfn)
>> {
>> struct page *page[1];
>> struct vm_area_struct *vma;
>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
>> int ret = -EFAULT;
>>
>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
>> + if (remote_mm) {
>> + down_read(&mm->mmap_sem);
>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
>> + !!(prot & IOMMU_WRITE), 0, page, NULL);
>
> Hi Kirti,
>
> It seems that get_user_pages_remote has only 7 args but you somehow gives 8
> here?
>
I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c:
long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
int write, int force, struct page **pages,
struct vm_area_struct **vmas)
{
return __get_user_pages_locked(tsk, mm, start, nr_pages, write,
force,
pages, vmas, NULL, false,
FOLL_TOUCH | FOLL_REMOTE);
}
EXPORT_SYMBOL(get_user_pages_remote);
Thanks,
Kirti
> --
> Thanks,
> Jike
>
>> + up_read(&mm->mmap_sem);
>> + } else
>> + ret = get_user_pages_fast(vaddr, 1,
>> + !!(prot & IOMMU_WRITE), page);
>> +
>> + if (ret == 1) {
>> *pfn = page_to_pfn(page[0]);
>> return 0;
>> }
>>
>> - down_read(¤t->mm->mmap_sem);
>> + down_read(&mm->mmap_sem);
>>
>> - vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
>> + vma = find_vma_intersection(mm, vaddr, vaddr + 1);
>>
>> if (vma && vma->vm_flags & VM_PFNMAP) {
>> *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
>> @@ -249,7 +260,7 @@ static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>> ret = 0;
>> }
>>
>> - up_read(¤t->mm->mmap_sem);
>> + up_read(&mm->mmap_sem);
>>
>> return ret;
>> }
>> @@ -270,7 +281,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
>> if (!current->mm)
>> return -ENODEV;
>>
>> - ret = vaddr_get_pfn(vaddr, prot, pfn_base);
>> + ret = vaddr_get_pfn(NULL, vaddr, prot, pfn_base);
>> if (ret)
>> return ret;
>>
>> @@ -293,7 +304,7 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
>> for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
>> unsigned long pfn = 0;
>>
>> - ret = vaddr_get_pfn(vaddr, prot, &pfn);
>> + ret = vaddr_get_pfn(NULL, vaddr, prot, &pfn);
>> if (ret)
>> break;
>>
>>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 19/19] docs: Sample driver to demonstrate how to use Mediated device framework.
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-27 14:29 ` Jonathan Corbet
-1 siblings, 0 replies; 119+ messages in thread
From: Jonathan Corbet @ 2016-10-27 14:29 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, jike.song, bjsdjshi, linux-kernel
On Thu, 27 Oct 2016 02:59:26 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> The Sample driver creates mdev device that simulates serial port over PCI
> card.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I857f8f12f8b275f2498dfe8c628a5cdc7193b1b2
> ---
> Documentation/vfio-mdev/Makefile | 13 +
> Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
> Documentation/vfio-mdev/vfio-mediated-device.txt | 103 +-
We've been working for a bit to get the buildable code *out* of the
documentation tree. I think this should go into samples/ instead.
Thanks,
jon
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 19/19] docs: Sample driver to demonstrate how to use Mediated device framework.
@ 2016-10-27 14:29 ` Jonathan Corbet
0 siblings, 0 replies; 119+ messages in thread
From: Jonathan Corbet @ 2016-10-27 14:29 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, jike.song, bjsdjshi, linux-kernel
On Thu, 27 Oct 2016 02:59:26 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> The Sample driver creates mdev device that simulates serial port over PCI
> card.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I857f8f12f8b275f2498dfe8c628a5cdc7193b1b2
> ---
> Documentation/vfio-mdev/Makefile | 13 +
> Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
> Documentation/vfio-mdev/vfio-mediated-device.txt | 103 +-
We've been working for a bit to get the buildable code *out* of the
documentation tree. I think this should go into samples/ instead.
Thanks,
jon
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 09/19] vfio iommu type1: Add support for mediated devices
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-27 23:01 ` Alex Williamson
-1 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-27 23:01 UTC (permalink / raw)
To: Kirti Wankhede
Cc: pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian, jike.song,
bjsdjshi, linux-kernel
On Thu, 27 Oct 2016 02:59:16 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> VFIO IOMMU drivers are designed for the devices which are IOMMU capable.
> Mediated device only uses IOMMU APIs, the underlying hardware can be
> managed by an IOMMU domain.
>
> Aim of this change is:
> - To use most of the code of TYPE1 IOMMU driver for mediated devices
> - To support direct assigned device and mediated device in single module
>
> This change adds pin and unpin support for mediated device to TYPE1 IOMMU
> backend module. More details:
> - When iommu_group of mediated devices is attached, task structure is
> cached which is used later to pin pages and page accounting.
> - It keeps track of pinned pages for mediated domain. This data is used to
> verify unpinning request and to unpin remaining pages while detaching, if
> there are any.
> - Used existing mechanism for page accounting. If iommu capable domain
> exist in the container then all pages are already pinned and accounted.
> Accouting for mdev device is only done if there is no iommu capable
> domain in the container.
> - Page accouting is updated on hot plug and unplug mdev device and pass
> through device.
>
> Tested by assigning below combinations of devices to a single VM:
> - GPU pass through only
> - vGPU device only
> - One GPU pass through and one vGPU device
> - Linux VM hot plug and unplug vGPU device while GPU pass through device
> exist
> - Linux VM hot plug and unplug GPU pass through device while vGPU device
> exist
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I295d6f0f2e0579b8d9882bfd8fd5a4194b97bd9a
> ---
> drivers/vfio/vfio_iommu_type1.c | 646 +++++++++++++++++++++++++++++++++++-----
> 1 file changed, 571 insertions(+), 75 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 861ac2a1b0c3..5add11a147e1 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -36,6 +36,7 @@
> #include <linux/uaccess.h>
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> +#include <linux/mdev.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -55,18 +56,26 @@ MODULE_PARM_DESC(disable_hugepages,
>
> struct vfio_iommu {
> struct list_head domain_list;
> + struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> bool v2;
> bool nesting;
> };
>
> +struct external_addr_space {
> + struct task_struct *task;
> + struct rb_root pfn_list; /* pinned Host pfn list */
> + struct mutex pfn_list_lock; /* mutex for pfn_list */
> +};
> +
> struct vfio_domain {
> - struct iommu_domain *domain;
> - struct list_head next;
> - struct list_head group_list;
> - int prot; /* IOMMU_CACHE */
> - bool fgsp; /* Fine-grained super pages */
> + struct iommu_domain *domain;
> + struct list_head next;
> + struct list_head group_list;
> + struct external_addr_space *external_addr_space;
> + int prot; /* IOMMU_CACHE */
> + bool fgsp; /* Fine-grained super pages */
> };
>
> struct vfio_dma {
> @@ -75,6 +84,7 @@ struct vfio_dma {
> unsigned long vaddr; /* Process virtual addr */
> size_t size; /* Map size (bytes) */
> int prot; /* IOMMU_READ/WRITE */
> + bool iommu_mapped;
> };
>
> struct vfio_group {
> @@ -83,6 +93,21 @@ struct vfio_group {
> };
>
> /*
> + * Guest RAM pinning working set or DMA target
> + */
> +struct vfio_pfn {
> + struct rb_node node;
> + unsigned long vaddr; /* virtual addr */
> + dma_addr_t iova; /* IOVA */
> + unsigned long pfn; /* Host pfn */
> + int prot;
> + atomic_t ref_count;
> +};
> +
> +#define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \
> + (!list_empty(&iommu->domain_list))
> +
> +/*
> * This code handles mapping and unmapping of user data buffers
> * into DMA'ble space using the IOMMU
> */
> @@ -130,6 +155,101 @@ static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
> rb_erase(&old->node, &iommu->dma_list);
> }
>
> +/*
> + * Helper Functions for host pfn list
> + */
> +
> +static struct vfio_pfn *vfio_find_pfn(struct vfio_domain *domain,
> + unsigned long pfn)
> +{
> + struct rb_node *node;
> + struct vfio_pfn *vpfn;
> +
> + node = domain->external_addr_space->pfn_list.rb_node;
> +
> + while (node) {
> + vpfn = rb_entry(node, struct vfio_pfn, node);
> +
> + if (pfn < vpfn->pfn)
> + node = node->rb_left;
> + else if (pfn > vpfn->pfn)
> + node = node->rb_right;
> + else
> + return vpfn;
> + }
> +
> + return NULL;
> +}
> +
> +static void vfio_link_pfn(struct vfio_domain *domain, struct vfio_pfn *new)
> +{
> + struct rb_node **link, *parent = NULL;
> + struct vfio_pfn *vpfn;
> +
> + link = &domain->external_addr_space->pfn_list.rb_node;
> + while (*link) {
> + parent = *link;
> + vpfn = rb_entry(parent, struct vfio_pfn, node);
> +
> + if (new->pfn < vpfn->pfn)
> + link = &(*link)->rb_left;
> + else
> + link = &(*link)->rb_right;
> + }
> +
> + rb_link_node(&new->node, parent, link);
> + rb_insert_color(&new->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static void vfio_unlink_pfn(struct vfio_domain *domain, struct vfio_pfn *old)
> +{
> + rb_erase(&old->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static int vfio_add_to_pfn_list(struct vfio_domain *domain, unsigned long vaddr,
> + dma_addr_t iova, unsigned long pfn, int prot)
> +{
> + struct vfio_pfn *vpfn;
> +
> + vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
> + if (!vpfn)
> + return -ENOMEM;
> +
> + vpfn->vaddr = vaddr;
> + vpfn->iova = iova;
> + vpfn->pfn = pfn;
> + vpfn->prot = prot;
> + atomic_set(&vpfn->ref_count, 1);
> + vfio_link_pfn(domain, vpfn);
> + return 0;
> +}
> +
> +static void vfio_remove_from_pfn_list(struct vfio_domain *domain,
> + struct vfio_pfn *vpfn)
> +{
> + vfio_unlink_pfn(domain, vpfn);
> + kfree(vpfn);
> +}
> +
> +static int vfio_pfn_account(struct vfio_iommu *iommu, unsigned long pfn)
> +{
> + struct vfio_pfn *p;
> + struct vfio_domain *domain = iommu->external_domain;
> + int ret = 1;
> +
> + if (!domain)
> + return 1;
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + p = vfio_find_pfn(domain, pfn);
> + if (p)
> + ret = 0;
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> + return ret;
> +}
> +
> struct vwork {
> struct mm_struct *mm;
> long npage;
> @@ -270,12 +390,13 @@ static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
> * the iommu can only map chunks of consecutive pfns anyway, so get the
> * first page and all consecutive pages with the same locking.
> */
> -static long vfio_pin_pages(unsigned long vaddr, long npage,
> - int prot, unsigned long *pfn_base)
> +static long __vfio_pin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long vaddr, long npage,
> + int prot, unsigned long *pfn_base)
> {
> unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> bool lock_cap = capable(CAP_IPC_LOCK);
> - long ret, i;
> + long ret, i, lock_acct = 0;
Initialization to zero is unnecessary here
> bool rsvd;
>
> if (!current->mm)
> @@ -285,9 +406,11 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> if (ret)
> return ret;
>
> + lock_acct = vfio_pfn_account(iommu, *pfn_base);
> +
> rsvd = is_invalid_reserved_pfn(*pfn_base);
>
> - if (!rsvd && !lock_cap && current->mm->locked_vm + 1 > limit) {
> + if (!rsvd && !lock_cap && current->mm->locked_vm + lock_acct > limit) {
> put_pfn(*pfn_base, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
> limit << PAGE_SHIFT);
> @@ -314,8 +437,10 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> break;
> }
>
> + lock_acct += vfio_pfn_account(iommu, pfn);
> +
> if (!rsvd && !lock_cap &&
> - current->mm->locked_vm + i + 1 > limit) {
> + current->mm->locked_vm + lock_acct > limit) {
> put_pfn(pfn, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
> __func__, limit << PAGE_SHIFT);
> @@ -329,14 +454,19 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> return i;
> }
>
> -static long vfio_unpin_pages(unsigned long pfn, long npage,
> - int prot, bool do_accounting)
> +static long __vfio_unpin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long pfn, long npage, int prot,
> + bool do_accounting)
> {
> - unsigned long unlocked = 0;
> + unsigned long unlocked = 0, unlock_acct = 0;
> long i;
>
> - for (i = 0; i < npage; i++)
> + for (i = 0; i < npage; i++) {
> + if (do_accounting)
> + unlock_acct += vfio_pfn_account(iommu, pfn);
> +
> unlocked += put_pfn(pfn++, prot);
> + }
Something is wrong here, we never do anything with unlock_acct
>
> if (do_accounting)
> vfio_lock_acct(current, -unlocked);
> @@ -344,14 +474,208 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
> return unlocked;
> }
>
> -static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
> +static long __vfio_pin_page_external(struct vfio_domain *domain,
> + unsigned long vaddr, int prot,
> + unsigned long *pfn_base,
> + bool do_accounting)
> +{
> + unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> + bool lock_cap = capable(CAP_IPC_LOCK);
capable() checks if the current user has this capability, but this path
is not user invoked. Whose capabilities are we testing here?
> + long ret;
> + bool rsvd;
> + struct task_struct *task = domain->external_addr_space->task;
@task is set from @current when the group is attached, did we get a
reference to that task, how do we know it's still valid? Could a given
vfio_dma use a different task_struct? I think these are the kinds of
issues Alexey was noting.
> +
> + if (!task->mm)
> + return -ENODEV;
> +
> + ret = vaddr_get_pfn(task->mm, vaddr, prot, pfn_base);
> + if (ret)
> + return ret;
> +
> + rsvd = is_invalid_reserved_pfn(*pfn_base);
> +
> + if (!rsvd && !lock_cap && task->mm->locked_vm + 1 > limit) {
> + put_pfn(*pfn_base, prot);
> + pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
> + limit << PAGE_SHIFT);
This happens when the vendor driver tries to pin pages, asynchronous to
any discernible user action, what are we supposed to do when we see
this in dmesg? How can we actually figure out what this is associated
with?
> + return -ENOMEM;
> + }
> +
> + if (!rsvd && do_accounting)
> + vfio_lock_acct(task, 1);
> +
> + return 1;
> +}
> +
> +static void __vfio_unpin_page_external(struct vfio_domain *domain,
> + unsigned long pfn, int prot,
> + bool do_accounting)
> +{
> + put_pfn(pfn, prot);
> +
> + if (do_accounting)
> + vfio_lock_acct(domain->external_addr_space->task, -1);
What if this task no longer exists.
> +}
> +
> +static int vfio_unpin_pfn(struct vfio_domain *domain,
> + struct vfio_pfn *vpfn, bool do_accounting)
> +{
> + __vfio_unpin_page_external(domain, vpfn->pfn, vpfn->prot,
> + do_accounting);
> +
> + if (atomic_dec_and_test(&vpfn->ref_count))
> + vfio_remove_from_pfn_list(domain, vpfn);
> +
> + return 1;
> +}
> +
> +static long vfio_iommu_type1_pin_pages(void *iommu_data,
> + unsigned long *user_pfn,
> + long npage, int prot,
> + unsigned long *phys_pfn)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> + struct vfio_domain *domain;
> + struct external_addr_space *addr_space;
> + int i, j, ret;
> + long retpage;
> + unsigned long remote_vaddr;
> + unsigned long *pfn = phys_pfn;
> + struct vfio_dma *dma;
> + bool do_accounting;
> +
> + if (!iommu || !user_pfn || !phys_pfn)
> + return -EINVAL;
> +
> + mutex_lock(&iommu->lock);
> +
> + if (!iommu->external_domain) {
> + ret = -EINVAL;
> + goto pin_done;
> + }
> +
> + domain = iommu->external_domain;
> + addr_space = domain->external_addr_space;
> + /*
> + * If iommu capable domain exist in the container then all pages are
> + * already pinned and accounted. Accouting should be done if there is no
> + * iommu capable domain in the container.
> + */
> + do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
> +
> + for (i = 0; i < npage; i++) {
> + struct vfio_pfn *p;
> + dma_addr_t iova;
> +
> + iova = user_pfn[i] << PAGE_SHIFT;
> +
> + dma = vfio_find_dma(iommu, iova, 0);
> + if (!dma) {
> + ret = -EINVAL;
> + goto pin_unwind;
> + }
> +
> + remote_vaddr = dma->vaddr + iova - dma->iova;
> +
> + retpage = __vfio_pin_page_external(domain, remote_vaddr, prot,
> + &pfn[i], do_accounting);
> + if (retpage <= 0) {
> + WARN_ON(!retpage);
> + ret = (int)retpage;
> + goto pin_unwind;
> + }
> +
> + mutex_lock(&addr_space->pfn_list_lock);
> +
> + /* search if pfn exist */
> + p = vfio_find_pfn(domain, pfn[i]);
> + if (p) {
if @do_accounting is true, aren't we now double accounting this pfn. I
think we're trying to pin it twice, but not account for it twice. Also
the problem with what if the user is running right at their locked
memory limit and the vendor driver pins a page (maybe it's already
pinned by another vendor driver), they're going to cross the limit when
really that page has already been accounted.
> + atomic_inc(&p->ref_count);
> + mutex_unlock(&addr_space->pfn_list_lock);
> + continue;
> + }
> +
> + ret = vfio_add_to_pfn_list(domain, remote_vaddr, iova,
> + pfn[i], prot);
> + mutex_unlock(&addr_space->pfn_list_lock);
> +
> + if (ret) {
> + __vfio_unpin_page_external(domain, pfn[i], prot,
> + do_accounting);
> + goto pin_unwind;
> + }
> + }
> +
> + ret = i;
> + goto pin_done;
> +
> +pin_unwind:
> + pfn[i] = 0;
> + mutex_lock(&addr_space->pfn_list_lock);
> + for (j = 0; j < i; j++) {
> + struct vfio_pfn *p;
> +
> + p = vfio_find_pfn(domain, pfn[j]);
> + if (p)
> + vfio_unpin_pfn(domain, p, do_accounting);
> +
> + pfn[j] = 0;
> + }
> + mutex_unlock(&addr_space->pfn_list_lock);
> +
> +pin_done:
> + mutex_unlock(&iommu->lock);
> + return ret;
> +}
> +
> +static long vfio_iommu_type1_unpin_pages(void *iommu_data, unsigned long *pfn,
> + long npage)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> + struct vfio_domain *domain = NULL;
> + bool do_accounting;
> + long unlocked = 0;
> + int i;
> +
> + if (!iommu || !pfn)
> + return -EINVAL;
> +
> + mutex_lock(&iommu->lock);
> +
> + domain = iommu->external_domain;
> +
> + do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + for (i = 0; i < npage; i++) {
> + struct vfio_pfn *p;
> +
> + /* verify if pfn exist in pfn_list */
> + p = vfio_find_pfn(domain, pfn[i]);
> + if (p)
> + unlocked += vfio_unpin_pfn(domain, p, do_accounting);
> +
> + }
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +
> + mutex_unlock(&iommu->lock);
> + return unlocked;
> +}
> +
> +static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
> + bool do_accounting)
> {
> dma_addr_t iova = dma->iova, end = dma->iova + dma->size;
> struct vfio_domain *domain, *d;
> long unlocked = 0;
>
> if (!dma->size)
> - return;
> + return 0;
> +
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
> + return 0;
> +
> /*
> * We use the IOMMU to track the physical addresses, otherwise we'd
> * need a much more complicated tracking system. Unfortunately that
> @@ -393,20 +717,27 @@ static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
> if (WARN_ON(!unmapped))
> break;
>
> - unlocked += vfio_unpin_pages(phys >> PAGE_SHIFT,
> - unmapped >> PAGE_SHIFT,
> - dma->prot, false);
> + unlocked += __vfio_unpin_pages_remote(iommu, phys >> PAGE_SHIFT,
> + unmapped >> PAGE_SHIFT,
> + dma->prot, false);
> iova += unmapped;
>
> cond_resched();
> }
>
> - vfio_lock_acct(current, -unlocked);
> + dma->iommu_mapped = false;
> +
> + if (do_accounting) {
> + vfio_lock_acct(current, -unlocked);
> + return 0;
> + }
> +
> + return unlocked;
> }
>
> static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
> {
> - vfio_unmap_unpin(iommu, dma);
> + vfio_unmap_unpin(iommu, dma, true);
> vfio_unlink_dma(iommu, dma);
> kfree(dma);
> }
> @@ -569,17 +900,57 @@ unwind:
> return ret;
> }
>
> +static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma,
> + size_t map_size)
> +{
> + dma_addr_t iova = dma->iova;
> + unsigned long vaddr = dma->vaddr;
> + size_t size = map_size;
> + long npage;
> + unsigned long pfn;
> + int ret = 0;
> +
> + while (size) {
> + /* Pin a contiguous chunk of memory */
> + npage = __vfio_pin_pages_remote(iommu, vaddr + dma->size,
> + size >> PAGE_SHIFT, dma->prot,
> + &pfn);
> + if (npage <= 0) {
> + WARN_ON(!npage);
> + ret = (int)npage;
> + break;
> + }
> +
> + /* Map it! */
> + ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage,
> + dma->prot);
> + if (ret) {
> + __vfio_unpin_pages_remote(iommu, pfn, npage, dma->prot,
> + true);
> + break;
> + }
> +
> + size -= npage << PAGE_SHIFT;
> + dma->size += npage << PAGE_SHIFT;
> + }
> +
> + dma->iommu_mapped = true;
> +
> + if (ret)
> + vfio_remove_dma(iommu, dma);
> +
> + return ret;
> +}
> +
> static int vfio_dma_do_map(struct vfio_iommu *iommu,
> struct vfio_iommu_type1_dma_map *map)
> {
> dma_addr_t iova = map->iova;
> unsigned long vaddr = map->vaddr;
> size_t size = map->size;
> - long npage;
> int ret = 0, prot = 0;
> uint64_t mask;
> struct vfio_dma *dma;
> - unsigned long pfn;
>
> /* Verify that none of our __u64 fields overflow */
> if (map->size != size || map->vaddr != vaddr || map->iova != iova)
> @@ -622,29 +993,11 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
> /* Insert zero-sized and grow as we map chunks of it */
> vfio_link_dma(iommu, dma);
>
> - while (size) {
> - /* Pin a contiguous chunk of memory */
> - npage = vfio_pin_pages(vaddr + dma->size,
> - size >> PAGE_SHIFT, prot, &pfn);
> - if (npage <= 0) {
> - WARN_ON(!npage);
> - ret = (int)npage;
> - break;
> - }
> -
> - /* Map it! */
> - ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage, prot);
> - if (ret) {
> - vfio_unpin_pages(pfn, npage, prot, true);
> - break;
> - }
> -
> - size -= npage << PAGE_SHIFT;
> - dma->size += npage << PAGE_SHIFT;
> - }
> -
> - if (ret)
> - vfio_remove_dma(iommu, dma);
> + /* Don't pin and map if container doesn't contain IOMMU capable domain*/
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
> + dma->size = size;
> + else
> + ret = vfio_pin_map_dma(iommu, dma, size);
>
> mutex_unlock(&iommu->lock);
> return ret;
> @@ -673,10 +1026,6 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
> d = list_first_entry(&iommu->domain_list, struct vfio_domain, next);
> n = rb_first(&iommu->dma_list);
>
> - /* If there's not a domain, there better not be any mappings */
> - if (WARN_ON(n && !d))
> - return -EINVAL;
> -
> for (; n; n = rb_next(n)) {
> struct vfio_dma *dma;
> dma_addr_t iova;
> @@ -685,20 +1034,43 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
> iova = dma->iova;
>
> while (iova < dma->iova + dma->size) {
> - phys_addr_t phys = iommu_iova_to_phys(d->domain, iova);
> + phys_addr_t phys;
> size_t size;
>
> - if (WARN_ON(!phys)) {
> - iova += PAGE_SIZE;
> - continue;
> - }
> + if (dma->iommu_mapped) {
> + phys = iommu_iova_to_phys(d->domain, iova);
>
> - size = PAGE_SIZE;
> + if (WARN_ON(!phys)) {
> + iova += PAGE_SIZE;
> + continue;
> + }
>
> - while (iova + size < dma->iova + dma->size &&
> - phys + size == iommu_iova_to_phys(d->domain,
> + size = PAGE_SIZE;
> +
> + while (iova + size < dma->iova + dma->size &&
> + phys + size == iommu_iova_to_phys(d->domain,
> iova + size))
> - size += PAGE_SIZE;
> + size += PAGE_SIZE;
> + } else {
> + unsigned long pfn;
> + unsigned long vaddr = dma->vaddr +
> + (iova - dma->iova);
> + size_t n = dma->iova + dma->size - iova;
> + long npage;
> +
> + npage = __vfio_pin_pages_remote(iommu, vaddr,
> + n >> PAGE_SHIFT,
> + dma->prot,
> + &pfn);
> + if (npage <= 0) {
> + WARN_ON(!npage);
> + ret = (int)npage;
> + return ret;
> + }
> +
> + phys = pfn << PAGE_SHIFT;
> + size = npage << PAGE_SHIFT;
> + }
>
> ret = iommu_map(domain->domain, iova, phys,
> size, dma->prot | domain->prot);
> @@ -707,6 +1079,8 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
>
> iova += size;
> }
> +
> + dma->iommu_mapped = true;
> }
>
> return 0;
> @@ -764,7 +1138,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> struct vfio_iommu *iommu = iommu_data;
> struct vfio_group *group;
> struct vfio_domain *domain, *d;
> - struct bus_type *bus = NULL;
> + struct bus_type *bus = NULL, *mdev_bus;
> int ret;
>
> mutex_lock(&iommu->lock);
> @@ -776,6 +1150,13 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> }
> }
>
> + if (iommu->external_domain) {
> + if (find_iommu_group(iommu->external_domain, iommu_group)) {
> + mutex_unlock(&iommu->lock);
> + return -EINVAL;
> + }
> + }
> +
> group = kzalloc(sizeof(*group), GFP_KERNEL);
> domain = kzalloc(sizeof(*domain), GFP_KERNEL);
> if (!group || !domain) {
> @@ -790,6 +1171,38 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> if (ret)
> goto out_free;
>
> + mdev_bus = symbol_get(mdev_bus_type);
> +
> + if (mdev_bus) {
> + if ((bus == mdev_bus) && !iommu_present(bus)) {
> + symbol_put(mdev_bus_type);
> + if (!iommu->external_domain) {
> + struct external_addr_space *addr_space;
> +
> + addr_space = kzalloc(sizeof(*addr_space),
> + GFP_KERNEL);
> + if (!addr_space) {
> + ret = -ENOMEM;
> + goto out_free;
> + }
> +
> + INIT_LIST_HEAD(&domain->group_list);
> + addr_space->task = current;
Regarding current here, could one process open the vfio container and
vfio group and perform this operation, then pass the file descriptors
for each to another task via SCM_RIGHTS? I don't think we can prevent
it. Wouldn't that mean the vendor driver is pinning pages in the
wrong task_struct? Do we need to track (and reference) the task_struct
for each vfio_dma? Maybe we need this anyway so that only the
task_struct that performed a DMA_MAP can do a DMA_UNMAP of that range.
> + addr_space->pfn_list = RB_ROOT;
> + mutex_init(&addr_space->pfn_list_lock);
> + domain->external_addr_space = addr_space;
> + iommu->external_domain = domain;
> + } else
> + kfree(domain);
> +
> + list_add(&group->next,
> + &iommu->external_domain->group_list);
> + mutex_unlock(&iommu->lock);
> + return 0;
> + }
> + symbol_put(mdev_bus_type);
> + }
> +
> domain->domain = iommu_domain_alloc(bus);
> if (!domain->domain) {
> ret = -EIO;
> @@ -880,6 +1293,42 @@ static void vfio_iommu_unmap_unpin_all(struct vfio_iommu *iommu)
> vfio_remove_dma(iommu, rb_entry(node, struct vfio_dma, node));
> }
>
> +static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu)
> +{
> + struct vfio_domain *domain = iommu->external_domain;
> + struct vfio_dma *dma, *tdma;
> + struct rb_node *n;
> + long locked = 0, unlocked = 0;
> +
> + rbtree_postorder_for_each_entry_safe(dma, tdma, &iommu->dma_list,
> + node) {
> + unlocked += vfio_unmap_unpin(iommu, dma, false);
> + }
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + n = rb_first(&domain->external_addr_space->pfn_list);
> +
> + for (; n; n = rb_next(n))
> + locked++;
> +
> + vfio_lock_acct(domain->external_addr_space->task, locked - unlocked);
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +}
> +
> +static void vfio_external_unpin_all(struct vfio_domain *domain,
> + bool do_accounting)
> +{
> + struct rb_node *node;
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> + while ((node = rb_first(&domain->external_addr_space->pfn_list)))
> + vfio_unpin_pfn(domain, rb_entry(node, struct vfio_pfn, node),
> + do_accounting);
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +}
> +
> static void vfio_iommu_type1_detach_group(void *iommu_data,
> struct iommu_group *iommu_group)
> {
> @@ -889,6 +1338,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> + if (iommu->external_domain) {
> + domain = iommu->external_domain;
> + group = find_iommu_group(domain, iommu_group);
> + if (group) {
> + list_del(&group->next);
> + kfree(group);
> +
> + if (list_empty(&domain->group_list)) {
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) {
> + vfio_external_unpin_all(domain, true);
> + vfio_iommu_unmap_unpin_all(iommu);
> + } else
> + vfio_external_unpin_all(domain, false);
> + kfree(domain);
> + iommu->external_domain = NULL;
> + }
> + goto detach_group_done;
> + }
> + }
> +
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
> + goto detach_group_done;
>
> list_for_each_entry(domain, &iommu->domain_list, next) {
> group = find_iommu_group(domain, iommu_group);
> @@ -899,21 +1370,27 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
> list_del(&group->next);
> kfree(group);
> /*
> - * Group ownership provides privilege, if the group
> - * list is empty, the domain goes away. If it's the
> - * last domain, then all the mappings go away too.
> + * Group ownership provides privilege, if the group list is
> + * empty, the domain goes away. If it's the last domain with
> + * iommu and external domain doesn't exist, then all the
> + * mappings go away too. If it's the last domain with iommu and
> + * external domain exist, update accounting
> */
> if (list_empty(&domain->group_list)) {
> - if (list_is_singular(&iommu->domain_list))
> - vfio_iommu_unmap_unpin_all(iommu);
> + if (list_is_singular(&iommu->domain_list)) {
> + if (!iommu->external_domain)
> + vfio_iommu_unmap_unpin_all(iommu);
> + else
> + vfio_iommu_unmap_unpin_reaccount(iommu);
> + }
> iommu_domain_free(domain->domain);
> list_del(&domain->next);
> kfree(domain);
> }
> - goto done;
> + break;
> }
>
> -done:
> +detach_group_done:
> mutex_unlock(&iommu->lock);
> }
>
> @@ -945,23 +1422,40 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> return iommu;
> }
>
> +static void vfio_release_domain(struct vfio_domain *domain)
> +{
> + struct vfio_group *group, *group_tmp;
> +
> + list_for_each_entry_safe(group, group_tmp,
> + &domain->group_list, next) {
> + if (!domain->external_addr_space)
> + iommu_detach_group(domain->domain, group->iommu_group);
> + list_del(&group->next);
> + kfree(group);
> + }
> +
> + if (domain->external_addr_space)
> + vfio_external_unpin_all(domain, false);
> + else
> + iommu_domain_free(domain->domain);
> +}
> +
> static void vfio_iommu_type1_release(void *iommu_data)
> {
> struct vfio_iommu *iommu = iommu_data;
> struct vfio_domain *domain, *domain_tmp;
> - struct vfio_group *group, *group_tmp;
> +
> + if (iommu->external_domain) {
> + vfio_release_domain(iommu->external_domain);
> + kfree(iommu->external_domain);
> + iommu->external_domain = NULL;
> + }
>
> vfio_iommu_unmap_unpin_all(iommu);
>
> list_for_each_entry_safe(domain, domain_tmp,
> &iommu->domain_list, next) {
> - list_for_each_entry_safe(group, group_tmp,
> - &domain->group_list, next) {
> - iommu_detach_group(domain->domain, group->iommu_group);
> - list_del(&group->next);
> - kfree(group);
> - }
> - iommu_domain_free(domain->domain);
> + vfio_release_domain(domain);
> list_del(&domain->next);
> kfree(domain);
> }
> @@ -1069,6 +1563,8 @@ static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> .ioctl = vfio_iommu_type1_ioctl,
> .attach_group = vfio_iommu_type1_attach_group,
> .detach_group = vfio_iommu_type1_detach_group,
> + .pin_pages = vfio_iommu_type1_pin_pages,
> + .unpin_pages = vfio_iommu_type1_unpin_pages,
> };
>
> static int __init vfio_iommu_type1_init(void)
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 09/19] vfio iommu type1: Add support for mediated devices
@ 2016-10-27 23:01 ` Alex Williamson
0 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-27 23:01 UTC (permalink / raw)
To: Kirti Wankhede
Cc: pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian, jike.song,
bjsdjshi, linux-kernel
On Thu, 27 Oct 2016 02:59:16 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> VFIO IOMMU drivers are designed for the devices which are IOMMU capable.
> Mediated device only uses IOMMU APIs, the underlying hardware can be
> managed by an IOMMU domain.
>
> Aim of this change is:
> - To use most of the code of TYPE1 IOMMU driver for mediated devices
> - To support direct assigned device and mediated device in single module
>
> This change adds pin and unpin support for mediated device to TYPE1 IOMMU
> backend module. More details:
> - When iommu_group of mediated devices is attached, task structure is
> cached which is used later to pin pages and page accounting.
> - It keeps track of pinned pages for mediated domain. This data is used to
> verify unpinning request and to unpin remaining pages while detaching, if
> there are any.
> - Used existing mechanism for page accounting. If iommu capable domain
> exist in the container then all pages are already pinned and accounted.
> Accouting for mdev device is only done if there is no iommu capable
> domain in the container.
> - Page accouting is updated on hot plug and unplug mdev device and pass
> through device.
>
> Tested by assigning below combinations of devices to a single VM:
> - GPU pass through only
> - vGPU device only
> - One GPU pass through and one vGPU device
> - Linux VM hot plug and unplug vGPU device while GPU pass through device
> exist
> - Linux VM hot plug and unplug GPU pass through device while vGPU device
> exist
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I295d6f0f2e0579b8d9882bfd8fd5a4194b97bd9a
> ---
> drivers/vfio/vfio_iommu_type1.c | 646 +++++++++++++++++++++++++++++++++++-----
> 1 file changed, 571 insertions(+), 75 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 861ac2a1b0c3..5add11a147e1 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -36,6 +36,7 @@
> #include <linux/uaccess.h>
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> +#include <linux/mdev.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -55,18 +56,26 @@ MODULE_PARM_DESC(disable_hugepages,
>
> struct vfio_iommu {
> struct list_head domain_list;
> + struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> bool v2;
> bool nesting;
> };
>
> +struct external_addr_space {
> + struct task_struct *task;
> + struct rb_root pfn_list; /* pinned Host pfn list */
> + struct mutex pfn_list_lock; /* mutex for pfn_list */
> +};
> +
> struct vfio_domain {
> - struct iommu_domain *domain;
> - struct list_head next;
> - struct list_head group_list;
> - int prot; /* IOMMU_CACHE */
> - bool fgsp; /* Fine-grained super pages */
> + struct iommu_domain *domain;
> + struct list_head next;
> + struct list_head group_list;
> + struct external_addr_space *external_addr_space;
> + int prot; /* IOMMU_CACHE */
> + bool fgsp; /* Fine-grained super pages */
> };
>
> struct vfio_dma {
> @@ -75,6 +84,7 @@ struct vfio_dma {
> unsigned long vaddr; /* Process virtual addr */
> size_t size; /* Map size (bytes) */
> int prot; /* IOMMU_READ/WRITE */
> + bool iommu_mapped;
> };
>
> struct vfio_group {
> @@ -83,6 +93,21 @@ struct vfio_group {
> };
>
> /*
> + * Guest RAM pinning working set or DMA target
> + */
> +struct vfio_pfn {
> + struct rb_node node;
> + unsigned long vaddr; /* virtual addr */
> + dma_addr_t iova; /* IOVA */
> + unsigned long pfn; /* Host pfn */
> + int prot;
> + atomic_t ref_count;
> +};
> +
> +#define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \
> + (!list_empty(&iommu->domain_list))
> +
> +/*
> * This code handles mapping and unmapping of user data buffers
> * into DMA'ble space using the IOMMU
> */
> @@ -130,6 +155,101 @@ static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
> rb_erase(&old->node, &iommu->dma_list);
> }
>
> +/*
> + * Helper Functions for host pfn list
> + */
> +
> +static struct vfio_pfn *vfio_find_pfn(struct vfio_domain *domain,
> + unsigned long pfn)
> +{
> + struct rb_node *node;
> + struct vfio_pfn *vpfn;
> +
> + node = domain->external_addr_space->pfn_list.rb_node;
> +
> + while (node) {
> + vpfn = rb_entry(node, struct vfio_pfn, node);
> +
> + if (pfn < vpfn->pfn)
> + node = node->rb_left;
> + else if (pfn > vpfn->pfn)
> + node = node->rb_right;
> + else
> + return vpfn;
> + }
> +
> + return NULL;
> +}
> +
> +static void vfio_link_pfn(struct vfio_domain *domain, struct vfio_pfn *new)
> +{
> + struct rb_node **link, *parent = NULL;
> + struct vfio_pfn *vpfn;
> +
> + link = &domain->external_addr_space->pfn_list.rb_node;
> + while (*link) {
> + parent = *link;
> + vpfn = rb_entry(parent, struct vfio_pfn, node);
> +
> + if (new->pfn < vpfn->pfn)
> + link = &(*link)->rb_left;
> + else
> + link = &(*link)->rb_right;
> + }
> +
> + rb_link_node(&new->node, parent, link);
> + rb_insert_color(&new->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static void vfio_unlink_pfn(struct vfio_domain *domain, struct vfio_pfn *old)
> +{
> + rb_erase(&old->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static int vfio_add_to_pfn_list(struct vfio_domain *domain, unsigned long vaddr,
> + dma_addr_t iova, unsigned long pfn, int prot)
> +{
> + struct vfio_pfn *vpfn;
> +
> + vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
> + if (!vpfn)
> + return -ENOMEM;
> +
> + vpfn->vaddr = vaddr;
> + vpfn->iova = iova;
> + vpfn->pfn = pfn;
> + vpfn->prot = prot;
> + atomic_set(&vpfn->ref_count, 1);
> + vfio_link_pfn(domain, vpfn);
> + return 0;
> +}
> +
> +static void vfio_remove_from_pfn_list(struct vfio_domain *domain,
> + struct vfio_pfn *vpfn)
> +{
> + vfio_unlink_pfn(domain, vpfn);
> + kfree(vpfn);
> +}
> +
> +static int vfio_pfn_account(struct vfio_iommu *iommu, unsigned long pfn)
> +{
> + struct vfio_pfn *p;
> + struct vfio_domain *domain = iommu->external_domain;
> + int ret = 1;
> +
> + if (!domain)
> + return 1;
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + p = vfio_find_pfn(domain, pfn);
> + if (p)
> + ret = 0;
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> + return ret;
> +}
> +
> struct vwork {
> struct mm_struct *mm;
> long npage;
> @@ -270,12 +390,13 @@ static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
> * the iommu can only map chunks of consecutive pfns anyway, so get the
> * first page and all consecutive pages with the same locking.
> */
> -static long vfio_pin_pages(unsigned long vaddr, long npage,
> - int prot, unsigned long *pfn_base)
> +static long __vfio_pin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long vaddr, long npage,
> + int prot, unsigned long *pfn_base)
> {
> unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> bool lock_cap = capable(CAP_IPC_LOCK);
> - long ret, i;
> + long ret, i, lock_acct = 0;
Initialization to zero is unnecessary here
> bool rsvd;
>
> if (!current->mm)
> @@ -285,9 +406,11 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> if (ret)
> return ret;
>
> + lock_acct = vfio_pfn_account(iommu, *pfn_base);
> +
> rsvd = is_invalid_reserved_pfn(*pfn_base);
>
> - if (!rsvd && !lock_cap && current->mm->locked_vm + 1 > limit) {
> + if (!rsvd && !lock_cap && current->mm->locked_vm + lock_acct > limit) {
> put_pfn(*pfn_base, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
> limit << PAGE_SHIFT);
> @@ -314,8 +437,10 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> break;
> }
>
> + lock_acct += vfio_pfn_account(iommu, pfn);
> +
> if (!rsvd && !lock_cap &&
> - current->mm->locked_vm + i + 1 > limit) {
> + current->mm->locked_vm + lock_acct > limit) {
> put_pfn(pfn, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
> __func__, limit << PAGE_SHIFT);
> @@ -329,14 +454,19 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> return i;
> }
>
> -static long vfio_unpin_pages(unsigned long pfn, long npage,
> - int prot, bool do_accounting)
> +static long __vfio_unpin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long pfn, long npage, int prot,
> + bool do_accounting)
> {
> - unsigned long unlocked = 0;
> + unsigned long unlocked = 0, unlock_acct = 0;
> long i;
>
> - for (i = 0; i < npage; i++)
> + for (i = 0; i < npage; i++) {
> + if (do_accounting)
> + unlock_acct += vfio_pfn_account(iommu, pfn);
> +
> unlocked += put_pfn(pfn++, prot);
> + }
Something is wrong here, we never do anything with unlock_acct
>
> if (do_accounting)
> vfio_lock_acct(current, -unlocked);
> @@ -344,14 +474,208 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
> return unlocked;
> }
>
> -static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
> +static long __vfio_pin_page_external(struct vfio_domain *domain,
> + unsigned long vaddr, int prot,
> + unsigned long *pfn_base,
> + bool do_accounting)
> +{
> + unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> + bool lock_cap = capable(CAP_IPC_LOCK);
capable() checks if the current user has this capability, but this path
is not user invoked. Whose capabilities are we testing here?
> + long ret;
> + bool rsvd;
> + struct task_struct *task = domain->external_addr_space->task;
@task is set from @current when the group is attached, did we get a
reference to that task, how do we know it's still valid? Could a given
vfio_dma use a different task_struct? I think these are the kinds of
issues Alexey was noting.
> +
> + if (!task->mm)
> + return -ENODEV;
> +
> + ret = vaddr_get_pfn(task->mm, vaddr, prot, pfn_base);
> + if (ret)
> + return ret;
> +
> + rsvd = is_invalid_reserved_pfn(*pfn_base);
> +
> + if (!rsvd && !lock_cap && task->mm->locked_vm + 1 > limit) {
> + put_pfn(*pfn_base, prot);
> + pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
> + limit << PAGE_SHIFT);
This happens when the vendor driver tries to pin pages, asynchronous to
any discernible user action, what are we supposed to do when we see
this in dmesg? How can we actually figure out what this is associated
with?
> + return -ENOMEM;
> + }
> +
> + if (!rsvd && do_accounting)
> + vfio_lock_acct(task, 1);
> +
> + return 1;
> +}
> +
> +static void __vfio_unpin_page_external(struct vfio_domain *domain,
> + unsigned long pfn, int prot,
> + bool do_accounting)
> +{
> + put_pfn(pfn, prot);
> +
> + if (do_accounting)
> + vfio_lock_acct(domain->external_addr_space->task, -1);
What if this task no longer exists.
> +}
> +
> +static int vfio_unpin_pfn(struct vfio_domain *domain,
> + struct vfio_pfn *vpfn, bool do_accounting)
> +{
> + __vfio_unpin_page_external(domain, vpfn->pfn, vpfn->prot,
> + do_accounting);
> +
> + if (atomic_dec_and_test(&vpfn->ref_count))
> + vfio_remove_from_pfn_list(domain, vpfn);
> +
> + return 1;
> +}
> +
> +static long vfio_iommu_type1_pin_pages(void *iommu_data,
> + unsigned long *user_pfn,
> + long npage, int prot,
> + unsigned long *phys_pfn)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> + struct vfio_domain *domain;
> + struct external_addr_space *addr_space;
> + int i, j, ret;
> + long retpage;
> + unsigned long remote_vaddr;
> + unsigned long *pfn = phys_pfn;
> + struct vfio_dma *dma;
> + bool do_accounting;
> +
> + if (!iommu || !user_pfn || !phys_pfn)
> + return -EINVAL;
> +
> + mutex_lock(&iommu->lock);
> +
> + if (!iommu->external_domain) {
> + ret = -EINVAL;
> + goto pin_done;
> + }
> +
> + domain = iommu->external_domain;
> + addr_space = domain->external_addr_space;
> + /*
> + * If iommu capable domain exist in the container then all pages are
> + * already pinned and accounted. Accouting should be done if there is no
> + * iommu capable domain in the container.
> + */
> + do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
> +
> + for (i = 0; i < npage; i++) {
> + struct vfio_pfn *p;
> + dma_addr_t iova;
> +
> + iova = user_pfn[i] << PAGE_SHIFT;
> +
> + dma = vfio_find_dma(iommu, iova, 0);
> + if (!dma) {
> + ret = -EINVAL;
> + goto pin_unwind;
> + }
> +
> + remote_vaddr = dma->vaddr + iova - dma->iova;
> +
> + retpage = __vfio_pin_page_external(domain, remote_vaddr, prot,
> + &pfn[i], do_accounting);
> + if (retpage <= 0) {
> + WARN_ON(!retpage);
> + ret = (int)retpage;
> + goto pin_unwind;
> + }
> +
> + mutex_lock(&addr_space->pfn_list_lock);
> +
> + /* search if pfn exist */
> + p = vfio_find_pfn(domain, pfn[i]);
> + if (p) {
if @do_accounting is true, aren't we now double accounting this pfn. I
think we're trying to pin it twice, but not account for it twice. Also
the problem with what if the user is running right at their locked
memory limit and the vendor driver pins a page (maybe it's already
pinned by another vendor driver), they're going to cross the limit when
really that page has already been accounted.
> + atomic_inc(&p->ref_count);
> + mutex_unlock(&addr_space->pfn_list_lock);
> + continue;
> + }
> +
> + ret = vfio_add_to_pfn_list(domain, remote_vaddr, iova,
> + pfn[i], prot);
> + mutex_unlock(&addr_space->pfn_list_lock);
> +
> + if (ret) {
> + __vfio_unpin_page_external(domain, pfn[i], prot,
> + do_accounting);
> + goto pin_unwind;
> + }
> + }
> +
> + ret = i;
> + goto pin_done;
> +
> +pin_unwind:
> + pfn[i] = 0;
> + mutex_lock(&addr_space->pfn_list_lock);
> + for (j = 0; j < i; j++) {
> + struct vfio_pfn *p;
> +
> + p = vfio_find_pfn(domain, pfn[j]);
> + if (p)
> + vfio_unpin_pfn(domain, p, do_accounting);
> +
> + pfn[j] = 0;
> + }
> + mutex_unlock(&addr_space->pfn_list_lock);
> +
> +pin_done:
> + mutex_unlock(&iommu->lock);
> + return ret;
> +}
> +
> +static long vfio_iommu_type1_unpin_pages(void *iommu_data, unsigned long *pfn,
> + long npage)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> + struct vfio_domain *domain = NULL;
> + bool do_accounting;
> + long unlocked = 0;
> + int i;
> +
> + if (!iommu || !pfn)
> + return -EINVAL;
> +
> + mutex_lock(&iommu->lock);
> +
> + domain = iommu->external_domain;
> +
> + do_accounting = !IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu);
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + for (i = 0; i < npage; i++) {
> + struct vfio_pfn *p;
> +
> + /* verify if pfn exist in pfn_list */
> + p = vfio_find_pfn(domain, pfn[i]);
> + if (p)
> + unlocked += vfio_unpin_pfn(domain, p, do_accounting);
> +
> + }
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +
> + mutex_unlock(&iommu->lock);
> + return unlocked;
> +}
> +
> +static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
> + bool do_accounting)
> {
> dma_addr_t iova = dma->iova, end = dma->iova + dma->size;
> struct vfio_domain *domain, *d;
> long unlocked = 0;
>
> if (!dma->size)
> - return;
> + return 0;
> +
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
> + return 0;
> +
> /*
> * We use the IOMMU to track the physical addresses, otherwise we'd
> * need a much more complicated tracking system. Unfortunately that
> @@ -393,20 +717,27 @@ static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
> if (WARN_ON(!unmapped))
> break;
>
> - unlocked += vfio_unpin_pages(phys >> PAGE_SHIFT,
> - unmapped >> PAGE_SHIFT,
> - dma->prot, false);
> + unlocked += __vfio_unpin_pages_remote(iommu, phys >> PAGE_SHIFT,
> + unmapped >> PAGE_SHIFT,
> + dma->prot, false);
> iova += unmapped;
>
> cond_resched();
> }
>
> - vfio_lock_acct(current, -unlocked);
> + dma->iommu_mapped = false;
> +
> + if (do_accounting) {
> + vfio_lock_acct(current, -unlocked);
> + return 0;
> + }
> +
> + return unlocked;
> }
>
> static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma)
> {
> - vfio_unmap_unpin(iommu, dma);
> + vfio_unmap_unpin(iommu, dma, true);
> vfio_unlink_dma(iommu, dma);
> kfree(dma);
> }
> @@ -569,17 +900,57 @@ unwind:
> return ret;
> }
>
> +static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma,
> + size_t map_size)
> +{
> + dma_addr_t iova = dma->iova;
> + unsigned long vaddr = dma->vaddr;
> + size_t size = map_size;
> + long npage;
> + unsigned long pfn;
> + int ret = 0;
> +
> + while (size) {
> + /* Pin a contiguous chunk of memory */
> + npage = __vfio_pin_pages_remote(iommu, vaddr + dma->size,
> + size >> PAGE_SHIFT, dma->prot,
> + &pfn);
> + if (npage <= 0) {
> + WARN_ON(!npage);
> + ret = (int)npage;
> + break;
> + }
> +
> + /* Map it! */
> + ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage,
> + dma->prot);
> + if (ret) {
> + __vfio_unpin_pages_remote(iommu, pfn, npage, dma->prot,
> + true);
> + break;
> + }
> +
> + size -= npage << PAGE_SHIFT;
> + dma->size += npage << PAGE_SHIFT;
> + }
> +
> + dma->iommu_mapped = true;
> +
> + if (ret)
> + vfio_remove_dma(iommu, dma);
> +
> + return ret;
> +}
> +
> static int vfio_dma_do_map(struct vfio_iommu *iommu,
> struct vfio_iommu_type1_dma_map *map)
> {
> dma_addr_t iova = map->iova;
> unsigned long vaddr = map->vaddr;
> size_t size = map->size;
> - long npage;
> int ret = 0, prot = 0;
> uint64_t mask;
> struct vfio_dma *dma;
> - unsigned long pfn;
>
> /* Verify that none of our __u64 fields overflow */
> if (map->size != size || map->vaddr != vaddr || map->iova != iova)
> @@ -622,29 +993,11 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
> /* Insert zero-sized and grow as we map chunks of it */
> vfio_link_dma(iommu, dma);
>
> - while (size) {
> - /* Pin a contiguous chunk of memory */
> - npage = vfio_pin_pages(vaddr + dma->size,
> - size >> PAGE_SHIFT, prot, &pfn);
> - if (npage <= 0) {
> - WARN_ON(!npage);
> - ret = (int)npage;
> - break;
> - }
> -
> - /* Map it! */
> - ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage, prot);
> - if (ret) {
> - vfio_unpin_pages(pfn, npage, prot, true);
> - break;
> - }
> -
> - size -= npage << PAGE_SHIFT;
> - dma->size += npage << PAGE_SHIFT;
> - }
> -
> - if (ret)
> - vfio_remove_dma(iommu, dma);
> + /* Don't pin and map if container doesn't contain IOMMU capable domain*/
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
> + dma->size = size;
> + else
> + ret = vfio_pin_map_dma(iommu, dma, size);
>
> mutex_unlock(&iommu->lock);
> return ret;
> @@ -673,10 +1026,6 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
> d = list_first_entry(&iommu->domain_list, struct vfio_domain, next);
> n = rb_first(&iommu->dma_list);
>
> - /* If there's not a domain, there better not be any mappings */
> - if (WARN_ON(n && !d))
> - return -EINVAL;
> -
> for (; n; n = rb_next(n)) {
> struct vfio_dma *dma;
> dma_addr_t iova;
> @@ -685,20 +1034,43 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
> iova = dma->iova;
>
> while (iova < dma->iova + dma->size) {
> - phys_addr_t phys = iommu_iova_to_phys(d->domain, iova);
> + phys_addr_t phys;
> size_t size;
>
> - if (WARN_ON(!phys)) {
> - iova += PAGE_SIZE;
> - continue;
> - }
> + if (dma->iommu_mapped) {
> + phys = iommu_iova_to_phys(d->domain, iova);
>
> - size = PAGE_SIZE;
> + if (WARN_ON(!phys)) {
> + iova += PAGE_SIZE;
> + continue;
> + }
>
> - while (iova + size < dma->iova + dma->size &&
> - phys + size == iommu_iova_to_phys(d->domain,
> + size = PAGE_SIZE;
> +
> + while (iova + size < dma->iova + dma->size &&
> + phys + size == iommu_iova_to_phys(d->domain,
> iova + size))
> - size += PAGE_SIZE;
> + size += PAGE_SIZE;
> + } else {
> + unsigned long pfn;
> + unsigned long vaddr = dma->vaddr +
> + (iova - dma->iova);
> + size_t n = dma->iova + dma->size - iova;
> + long npage;
> +
> + npage = __vfio_pin_pages_remote(iommu, vaddr,
> + n >> PAGE_SHIFT,
> + dma->prot,
> + &pfn);
> + if (npage <= 0) {
> + WARN_ON(!npage);
> + ret = (int)npage;
> + return ret;
> + }
> +
> + phys = pfn << PAGE_SHIFT;
> + size = npage << PAGE_SHIFT;
> + }
>
> ret = iommu_map(domain->domain, iova, phys,
> size, dma->prot | domain->prot);
> @@ -707,6 +1079,8 @@ static int vfio_iommu_replay(struct vfio_iommu *iommu,
>
> iova += size;
> }
> +
> + dma->iommu_mapped = true;
> }
>
> return 0;
> @@ -764,7 +1138,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> struct vfio_iommu *iommu = iommu_data;
> struct vfio_group *group;
> struct vfio_domain *domain, *d;
> - struct bus_type *bus = NULL;
> + struct bus_type *bus = NULL, *mdev_bus;
> int ret;
>
> mutex_lock(&iommu->lock);
> @@ -776,6 +1150,13 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> }
> }
>
> + if (iommu->external_domain) {
> + if (find_iommu_group(iommu->external_domain, iommu_group)) {
> + mutex_unlock(&iommu->lock);
> + return -EINVAL;
> + }
> + }
> +
> group = kzalloc(sizeof(*group), GFP_KERNEL);
> domain = kzalloc(sizeof(*domain), GFP_KERNEL);
> if (!group || !domain) {
> @@ -790,6 +1171,38 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> if (ret)
> goto out_free;
>
> + mdev_bus = symbol_get(mdev_bus_type);
> +
> + if (mdev_bus) {
> + if ((bus == mdev_bus) && !iommu_present(bus)) {
> + symbol_put(mdev_bus_type);
> + if (!iommu->external_domain) {
> + struct external_addr_space *addr_space;
> +
> + addr_space = kzalloc(sizeof(*addr_space),
> + GFP_KERNEL);
> + if (!addr_space) {
> + ret = -ENOMEM;
> + goto out_free;
> + }
> +
> + INIT_LIST_HEAD(&domain->group_list);
> + addr_space->task = current;
Regarding current here, could one process open the vfio container and
vfio group and perform this operation, then pass the file descriptors
for each to another task via SCM_RIGHTS? I don't think we can prevent
it. Wouldn't that mean the vendor driver is pinning pages in the
wrong task_struct? Do we need to track (and reference) the task_struct
for each vfio_dma? Maybe we need this anyway so that only the
task_struct that performed a DMA_MAP can do a DMA_UNMAP of that range.
> + addr_space->pfn_list = RB_ROOT;
> + mutex_init(&addr_space->pfn_list_lock);
> + domain->external_addr_space = addr_space;
> + iommu->external_domain = domain;
> + } else
> + kfree(domain);
> +
> + list_add(&group->next,
> + &iommu->external_domain->group_list);
> + mutex_unlock(&iommu->lock);
> + return 0;
> + }
> + symbol_put(mdev_bus_type);
> + }
> +
> domain->domain = iommu_domain_alloc(bus);
> if (!domain->domain) {
> ret = -EIO;
> @@ -880,6 +1293,42 @@ static void vfio_iommu_unmap_unpin_all(struct vfio_iommu *iommu)
> vfio_remove_dma(iommu, rb_entry(node, struct vfio_dma, node));
> }
>
> +static void vfio_iommu_unmap_unpin_reaccount(struct vfio_iommu *iommu)
> +{
> + struct vfio_domain *domain = iommu->external_domain;
> + struct vfio_dma *dma, *tdma;
> + struct rb_node *n;
> + long locked = 0, unlocked = 0;
> +
> + rbtree_postorder_for_each_entry_safe(dma, tdma, &iommu->dma_list,
> + node) {
> + unlocked += vfio_unmap_unpin(iommu, dma, false);
> + }
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + n = rb_first(&domain->external_addr_space->pfn_list);
> +
> + for (; n; n = rb_next(n))
> + locked++;
> +
> + vfio_lock_acct(domain->external_addr_space->task, locked - unlocked);
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +}
> +
> +static void vfio_external_unpin_all(struct vfio_domain *domain,
> + bool do_accounting)
> +{
> + struct rb_node *node;
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> + while ((node = rb_first(&domain->external_addr_space->pfn_list)))
> + vfio_unpin_pfn(domain, rb_entry(node, struct vfio_pfn, node),
> + do_accounting);
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +}
> +
> static void vfio_iommu_type1_detach_group(void *iommu_data,
> struct iommu_group *iommu_group)
> {
> @@ -889,6 +1338,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> + if (iommu->external_domain) {
> + domain = iommu->external_domain;
> + group = find_iommu_group(domain, iommu_group);
> + if (group) {
> + list_del(&group->next);
> + kfree(group);
> +
> + if (list_empty(&domain->group_list)) {
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) {
> + vfio_external_unpin_all(domain, true);
> + vfio_iommu_unmap_unpin_all(iommu);
> + } else
> + vfio_external_unpin_all(domain, false);
> + kfree(domain);
> + iommu->external_domain = NULL;
> + }
> + goto detach_group_done;
> + }
> + }
> +
> + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu))
> + goto detach_group_done;
>
> list_for_each_entry(domain, &iommu->domain_list, next) {
> group = find_iommu_group(domain, iommu_group);
> @@ -899,21 +1370,27 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
> list_del(&group->next);
> kfree(group);
> /*
> - * Group ownership provides privilege, if the group
> - * list is empty, the domain goes away. If it's the
> - * last domain, then all the mappings go away too.
> + * Group ownership provides privilege, if the group list is
> + * empty, the domain goes away. If it's the last domain with
> + * iommu and external domain doesn't exist, then all the
> + * mappings go away too. If it's the last domain with iommu and
> + * external domain exist, update accounting
> */
> if (list_empty(&domain->group_list)) {
> - if (list_is_singular(&iommu->domain_list))
> - vfio_iommu_unmap_unpin_all(iommu);
> + if (list_is_singular(&iommu->domain_list)) {
> + if (!iommu->external_domain)
> + vfio_iommu_unmap_unpin_all(iommu);
> + else
> + vfio_iommu_unmap_unpin_reaccount(iommu);
> + }
> iommu_domain_free(domain->domain);
> list_del(&domain->next);
> kfree(domain);
> }
> - goto done;
> + break;
> }
>
> -done:
> +detach_group_done:
> mutex_unlock(&iommu->lock);
> }
>
> @@ -945,23 +1422,40 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> return iommu;
> }
>
> +static void vfio_release_domain(struct vfio_domain *domain)
> +{
> + struct vfio_group *group, *group_tmp;
> +
> + list_for_each_entry_safe(group, group_tmp,
> + &domain->group_list, next) {
> + if (!domain->external_addr_space)
> + iommu_detach_group(domain->domain, group->iommu_group);
> + list_del(&group->next);
> + kfree(group);
> + }
> +
> + if (domain->external_addr_space)
> + vfio_external_unpin_all(domain, false);
> + else
> + iommu_domain_free(domain->domain);
> +}
> +
> static void vfio_iommu_type1_release(void *iommu_data)
> {
> struct vfio_iommu *iommu = iommu_data;
> struct vfio_domain *domain, *domain_tmp;
> - struct vfio_group *group, *group_tmp;
> +
> + if (iommu->external_domain) {
> + vfio_release_domain(iommu->external_domain);
> + kfree(iommu->external_domain);
> + iommu->external_domain = NULL;
> + }
>
> vfio_iommu_unmap_unpin_all(iommu);
>
> list_for_each_entry_safe(domain, domain_tmp,
> &iommu->domain_list, next) {
> - list_for_each_entry_safe(group, group_tmp,
> - &domain->group_list, next) {
> - iommu_detach_group(domain->domain, group->iommu_group);
> - list_del(&group->next);
> - kfree(group);
> - }
> - iommu_domain_free(domain->domain);
> + vfio_release_domain(domain);
> list_del(&domain->next);
> kfree(domain);
> }
> @@ -1069,6 +1563,8 @@ static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> .ioctl = vfio_iommu_type1_ioctl,
> .attach_group = vfio_iommu_type1_attach_group,
> .detach_group = vfio_iommu_type1_detach_group,
> + .pin_pages = vfio_iommu_type1_pin_pages,
> + .unpin_pages = vfio_iommu_type1_unpin_pages,
> };
>
> static int __init vfio_iommu_type1_init(void)
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
2016-10-27 12:24 ` Kirti Wankhede
@ 2016-10-28 6:01 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-28 6:01 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 08:24 PM, Kirti Wankhede wrote:
>
>
> On 10/27/2016 5:41 PM, Jike Song wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
>>> argument.
>>>
>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
>>> ---
>>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
>>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>>> index 72fee415044a..3d916b965492 100644
>>> --- a/drivers/vfio/vfio_iommu_type1.c
>>> +++ b/drivers/vfio/vfio_iommu_type1.c
>>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
>>> return 0;
>>> }
>>>
>>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
>>> + int prot, unsigned long *pfn)
>>> {
>>> struct page *page[1];
>>> struct vm_area_struct *vma;
>>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
>>> int ret = -EFAULT;
>>>
>>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
>>> + if (remote_mm) {
>>> + down_read(&mm->mmap_sem);
>>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
>>> + !!(prot & IOMMU_WRITE), 0, page, NULL);
>>
>> Hi Kirti,
>>
>> It seems that get_user_pages_remote has only 7 args but you somehow gives 8
>> here?
>>
>
> I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c:
>
> long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
> unsigned long start, unsigned long nr_pages,
> int write, int force, struct page **pages,
> struct vm_area_struct **vmas)
> {
> return __get_user_pages_locked(tsk, mm, start, nr_pages, write,
> force,
> pages, vmas, NULL, false,
> FOLL_TOUCH | FOLL_REMOTE);
> }
> EXPORT_SYMBOL(get_user_pages_remote);
It's queer. I checked:
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/mm/gup.c
It still has 7 args.
I believe you have seen this change somewhere, would you share the repo url
and branch name of the linux-next you based on?
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
@ 2016-10-28 6:01 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-28 6:01 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 08:24 PM, Kirti Wankhede wrote:
>
>
> On 10/27/2016 5:41 PM, Jike Song wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
>>> argument.
>>>
>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
>>> ---
>>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
>>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>>> index 72fee415044a..3d916b965492 100644
>>> --- a/drivers/vfio/vfio_iommu_type1.c
>>> +++ b/drivers/vfio/vfio_iommu_type1.c
>>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
>>> return 0;
>>> }
>>>
>>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
>>> + int prot, unsigned long *pfn)
>>> {
>>> struct page *page[1];
>>> struct vm_area_struct *vma;
>>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
>>> int ret = -EFAULT;
>>>
>>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
>>> + if (remote_mm) {
>>> + down_read(&mm->mmap_sem);
>>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
>>> + !!(prot & IOMMU_WRITE), 0, page, NULL);
>>
>> Hi Kirti,
>>
>> It seems that get_user_pages_remote has only 7 args but you somehow gives 8
>> here?
>>
>
> I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c:
>
> long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
> unsigned long start, unsigned long nr_pages,
> int write, int force, struct page **pages,
> struct vm_area_struct **vmas)
> {
> return __get_user_pages_locked(tsk, mm, start, nr_pages, write,
> force,
> pages, vmas, NULL, false,
> FOLL_TOUCH | FOLL_REMOTE);
> }
> EXPORT_SYMBOL(get_user_pages_remote);
It's queer. I checked:
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/mm/gup.c
It still has 7 args.
I believe you have seen this change somewhere, would you share the repo url
and branch name of the linux-next you based on?
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-28 7:33 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-28 7:33 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> about DMA_UNMAP.
> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> Vendor driver should register notifer using these APIs.
> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> mappings.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> ---
> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> include/linux/vfio.h | 11 +++++
> 3 files changed, 163 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 28b50ca14c52..ff05ac6b1e90 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1891,6 +1891,79 @@ err_unpin_pages:
> }
> EXPORT_SYMBOL(vfio_unpin_pages);
>
> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_register_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->register_notifier))
> + ret = driver->ops->register_notifier(container->iommu_data, nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_register_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_register_notifier);
> +
> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_unregister_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->unregister_notifier))
> + ret = driver->ops->unregister_notifier(container->iommu_data,
> + nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_unregister_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_unregister_notifier);
> +
> /**
> * Module/class support
> */
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 5add11a147e1..a4bd331ac0fd 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -37,6 +37,7 @@
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> #include <linux/mdev.h>
> +#include <linux/notifier.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -59,6 +60,7 @@ struct vfio_iommu {
> struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> + struct blocking_notifier_head notifier;
> bool v2;
> bool nesting;
> };
> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> - if (!iommu->external_domain) {
> + /* Fail if notifier list is empty */
> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> ret = -EINVAL;
> goto pin_done;
> }
> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> return bitmap;
> }
>
> +/*
> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> + * receiving notifier callback, vendor driver should invalidate the mapping and
> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> + * searching for next vfio_pfn in rb tree, start search from first node again.
> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> + * from rb tree and so in next search vfio_pfn would be same as previous
> + * vfio_pfn. In that case, exit from loop.
> + */
> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> + struct vfio_iommu_type1_dma_unmap *unmap)
> +{
> + struct vfio_domain *domain = iommu->external_domain;
> + struct rb_node *n;
> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> +
> + do {
> + prev_vpfn = vpfn;
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + n = rb_first(&domain->external_addr_space->pfn_list);
> +
> + for (; n; n = rb_next(n), vpfn = NULL) {
> + vpfn = rb_entry(n, struct vfio_pfn, node);
> +
> + if ((vpfn->iova >= unmap->iova) &&
> + (vpfn->iova < unmap->iova + unmap->size))
> + break;
> + }
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +
> + /* Notify any listeners about DMA_UNMAP */
> + if (vpfn)
> + blocking_notifier_call_chain(&iommu->notifier,
> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> + &vpfn->pfn);
Hi Kirti,
The information carried by notifier is only a pfn.
Since your pin/unpin interfaces design, it's the vendor driver who should
guarantee pin/unpin same times. To achieve that, the vendor driver must
cache it's iova->pfn mapping on its side, to avoid pinning a same page
for multiple times.
With the notifier carrying only a pfn, to find the iova by this pfn,
the vendor driver must *also* keep a reverse-mapping. That's a bit
too much.
Since the vendor could also suffer from IOMMU-compatible problem,
which means a local cache is always helpful, so I'd like to have the
iova carried to the notifier.
What'd you say?
--
Thanks,
Jike
> + } while (vpfn && (prev_vpfn != vpfn));
> +
> + WARN_ON(vpfn);
> +}
> +
> static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
> struct vfio_iommu_type1_dma_unmap *unmap)
> {
> @@ -844,6 +891,9 @@ unlock:
> /* Report how much was unmapped */
> unmap->size = unmapped;
>
> + if (unmapped && iommu->external_domain)
> + vfio_notifier_call_chain(iommu, unmap);
> +
> return ret;
> }
>
> @@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> INIT_LIST_HEAD(&iommu->domain_list);
> iommu->dma_list = RB_ROOT;
> mutex_init(&iommu->lock);
> + BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
>
> return iommu;
> }
> @@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
> return -ENOTTY;
> }
>
> +static int vfio_iommu_type1_register_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_register(&iommu->notifier, nb);
> +}
> +
> +static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_unregister(&iommu->notifier, nb);
> +}
> +
> static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> - .name = "vfio-iommu-type1",
> - .owner = THIS_MODULE,
> - .open = vfio_iommu_type1_open,
> - .release = vfio_iommu_type1_release,
> - .ioctl = vfio_iommu_type1_ioctl,
> - .attach_group = vfio_iommu_type1_attach_group,
> - .detach_group = vfio_iommu_type1_detach_group,
> - .pin_pages = vfio_iommu_type1_pin_pages,
> - .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .name = "vfio-iommu-type1",
> + .owner = THIS_MODULE,
> + .open = vfio_iommu_type1_open,
> + .release = vfio_iommu_type1_release,
> + .ioctl = vfio_iommu_type1_ioctl,
> + .attach_group = vfio_iommu_type1_attach_group,
> + .detach_group = vfio_iommu_type1_detach_group,
> + .pin_pages = vfio_iommu_type1_pin_pages,
> + .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .register_notifier = vfio_iommu_type1_register_notifier,
> + .unregister_notifier = vfio_iommu_type1_unregister_notifier,
> };
>
> static int __init vfio_iommu_type1_init(void)
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 0609a2052846..4c91ce8bfaeb 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
> unsigned long *phys_pfn);
> long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> long npage);
> + int (*register_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> + int (*unregister_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> };
>
> extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> @@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> long npage);
>
> +#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
> +
> +extern int vfio_register_notifier(struct device *dev,
> + struct notifier_block *nb);
> +
> +extern int vfio_unregister_notifier(struct device *dev,
> + struct notifier_block *nb);
> /*
> * IRQfd - generic
> */
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-28 7:33 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-28 7:33 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> about DMA_UNMAP.
> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> Vendor driver should register notifer using these APIs.
> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> mappings.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> ---
> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> include/linux/vfio.h | 11 +++++
> 3 files changed, 163 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 28b50ca14c52..ff05ac6b1e90 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1891,6 +1891,79 @@ err_unpin_pages:
> }
> EXPORT_SYMBOL(vfio_unpin_pages);
>
> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_register_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->register_notifier))
> + ret = driver->ops->register_notifier(container->iommu_data, nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_register_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_register_notifier);
> +
> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_unregister_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->unregister_notifier))
> + ret = driver->ops->unregister_notifier(container->iommu_data,
> + nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_unregister_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_unregister_notifier);
> +
> /**
> * Module/class support
> */
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 5add11a147e1..a4bd331ac0fd 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -37,6 +37,7 @@
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> #include <linux/mdev.h>
> +#include <linux/notifier.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -59,6 +60,7 @@ struct vfio_iommu {
> struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> + struct blocking_notifier_head notifier;
> bool v2;
> bool nesting;
> };
> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> - if (!iommu->external_domain) {
> + /* Fail if notifier list is empty */
> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> ret = -EINVAL;
> goto pin_done;
> }
> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> return bitmap;
> }
>
> +/*
> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> + * receiving notifier callback, vendor driver should invalidate the mapping and
> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> + * searching for next vfio_pfn in rb tree, start search from first node again.
> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> + * from rb tree and so in next search vfio_pfn would be same as previous
> + * vfio_pfn. In that case, exit from loop.
> + */
> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> + struct vfio_iommu_type1_dma_unmap *unmap)
> +{
> + struct vfio_domain *domain = iommu->external_domain;
> + struct rb_node *n;
> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> +
> + do {
> + prev_vpfn = vpfn;
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + n = rb_first(&domain->external_addr_space->pfn_list);
> +
> + for (; n; n = rb_next(n), vpfn = NULL) {
> + vpfn = rb_entry(n, struct vfio_pfn, node);
> +
> + if ((vpfn->iova >= unmap->iova) &&
> + (vpfn->iova < unmap->iova + unmap->size))
> + break;
> + }
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +
> + /* Notify any listeners about DMA_UNMAP */
> + if (vpfn)
> + blocking_notifier_call_chain(&iommu->notifier,
> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> + &vpfn->pfn);
Hi Kirti,
The information carried by notifier is only a pfn.
Since your pin/unpin interfaces design, it's the vendor driver who should
guarantee pin/unpin same times. To achieve that, the vendor driver must
cache it's iova->pfn mapping on its side, to avoid pinning a same page
for multiple times.
With the notifier carrying only a pfn, to find the iova by this pfn,
the vendor driver must *also* keep a reverse-mapping. That's a bit
too much.
Since the vendor could also suffer from IOMMU-compatible problem,
which means a local cache is always helpful, so I'd like to have the
iova carried to the notifier.
What'd you say?
--
Thanks,
Jike
> + } while (vpfn && (prev_vpfn != vpfn));
> +
> + WARN_ON(vpfn);
> +}
> +
> static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
> struct vfio_iommu_type1_dma_unmap *unmap)
> {
> @@ -844,6 +891,9 @@ unlock:
> /* Report how much was unmapped */
> unmap->size = unmapped;
>
> + if (unmapped && iommu->external_domain)
> + vfio_notifier_call_chain(iommu, unmap);
> +
> return ret;
> }
>
> @@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> INIT_LIST_HEAD(&iommu->domain_list);
> iommu->dma_list = RB_ROOT;
> mutex_init(&iommu->lock);
> + BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
>
> return iommu;
> }
> @@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
> return -ENOTTY;
> }
>
> +static int vfio_iommu_type1_register_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_register(&iommu->notifier, nb);
> +}
> +
> +static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_unregister(&iommu->notifier, nb);
> +}
> +
> static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> - .name = "vfio-iommu-type1",
> - .owner = THIS_MODULE,
> - .open = vfio_iommu_type1_open,
> - .release = vfio_iommu_type1_release,
> - .ioctl = vfio_iommu_type1_ioctl,
> - .attach_group = vfio_iommu_type1_attach_group,
> - .detach_group = vfio_iommu_type1_detach_group,
> - .pin_pages = vfio_iommu_type1_pin_pages,
> - .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .name = "vfio-iommu-type1",
> + .owner = THIS_MODULE,
> + .open = vfio_iommu_type1_open,
> + .release = vfio_iommu_type1_release,
> + .ioctl = vfio_iommu_type1_ioctl,
> + .attach_group = vfio_iommu_type1_attach_group,
> + .detach_group = vfio_iommu_type1_detach_group,
> + .pin_pages = vfio_iommu_type1_pin_pages,
> + .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .register_notifier = vfio_iommu_type1_register_notifier,
> + .unregister_notifier = vfio_iommu_type1_unregister_notifier,
> };
>
> static int __init vfio_iommu_type1_init(void)
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 0609a2052846..4c91ce8bfaeb 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
> unsigned long *phys_pfn);
> long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> long npage);
> + int (*register_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> + int (*unregister_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> };
>
> extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> @@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> long npage);
>
> +#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
> +
> +extern int vfio_register_notifier(struct device *dev,
> + struct notifier_block *nb);
> +
> +extern int vfio_unregister_notifier(struct device *dev,
> + struct notifier_block *nb);
> /*
> * IRQfd - generic
> */
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-28 7:33 ` [Qemu-devel] " Jike Song
@ 2016-10-28 12:38 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-28 12:38 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/28/2016 1:03 PM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>
>> +/*
>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>> + * from rb tree and so in next search vfio_pfn would be same as previous
>> + * vfio_pfn. In that case, exit from loop.
>> + */
>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>> + struct vfio_iommu_type1_dma_unmap *unmap)
>> +{
>> + struct vfio_domain *domain = iommu->external_domain;
>> + struct rb_node *n;
>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>> +
>> + do {
>> + prev_vpfn = vpfn;
>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>> +
>> + n = rb_first(&domain->external_addr_space->pfn_list);
>> +
>> + for (; n; n = rb_next(n), vpfn = NULL) {
>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>> +
>> + if ((vpfn->iova >= unmap->iova) &&
>> + (vpfn->iova < unmap->iova + unmap->size))
>> + break;
>> + }
>> +
>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>> +
>> + /* Notify any listeners about DMA_UNMAP */
>> + if (vpfn)
>> + blocking_notifier_call_chain(&iommu->notifier,
>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>> + &vpfn->pfn);
>
> Hi Kirti,
>
> The information carried by notifier is only a pfn.
>
> Since your pin/unpin interfaces design, it's the vendor driver who should
> guarantee pin/unpin same times.
That because there could be multiple mdev devices from different vendor
driver in a domain, and pin request for a page can come from multiple
vendor driver for same page and in pin/unpin page interface we don't
keep track of who had pinned pages. So its vendor driver's
responsibility to unpin pages which he had pinned.
> To achieve that, the vendor driver must
> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> for multiple times.
>
That's right.
> With the notifier carrying only a pfn, to find the iova by this pfn,
> the vendor driver must *also* keep a reverse-mapping. That's a bit
> too much.
>
Don't know what the reserve mapping is, vendor should know the pfn that
he has previously pinned to call the unpin anyway so there is no need to
duplicate the logic here.
Kirti
> Since the vendor could also suffer from IOMMU-compatible problem,
> which means a local cache is always helpful, so I'd like to have the
> iova carried to the notifier.
>
> What'd you say?
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-28 12:38 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-28 12:38 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/28/2016 1:03 PM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>
>> +/*
>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>> + * from rb tree and so in next search vfio_pfn would be same as previous
>> + * vfio_pfn. In that case, exit from loop.
>> + */
>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>> + struct vfio_iommu_type1_dma_unmap *unmap)
>> +{
>> + struct vfio_domain *domain = iommu->external_domain;
>> + struct rb_node *n;
>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>> +
>> + do {
>> + prev_vpfn = vpfn;
>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>> +
>> + n = rb_first(&domain->external_addr_space->pfn_list);
>> +
>> + for (; n; n = rb_next(n), vpfn = NULL) {
>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>> +
>> + if ((vpfn->iova >= unmap->iova) &&
>> + (vpfn->iova < unmap->iova + unmap->size))
>> + break;
>> + }
>> +
>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>> +
>> + /* Notify any listeners about DMA_UNMAP */
>> + if (vpfn)
>> + blocking_notifier_call_chain(&iommu->notifier,
>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>> + &vpfn->pfn);
>
> Hi Kirti,
>
> The information carried by notifier is only a pfn.
>
> Since your pin/unpin interfaces design, it's the vendor driver who should
> guarantee pin/unpin same times.
That because there could be multiple mdev devices from different vendor
driver in a domain, and pin request for a page can come from multiple
vendor driver for same page and in pin/unpin page interface we don't
keep track of who had pinned pages. So its vendor driver's
responsibility to unpin pages which he had pinned.
> To achieve that, the vendor driver must
> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> for multiple times.
>
That's right.
> With the notifier carrying only a pfn, to find the iova by this pfn,
> the vendor driver must *also* keep a reverse-mapping. That's a bit
> too much.
>
Don't know what the reserve mapping is, vendor should know the pfn that
he has previously pinned to call the unpin anyway so there is no need to
duplicate the logic here.
Kirti
> Since the vendor could also suffer from IOMMU-compatible problem,
> which means a local cache is always helpful, so I'd like to have the
> iova carried to the notifier.
>
> What'd you say?
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-28 7:33 ` [Qemu-devel] " Jike Song
@ 2016-10-28 12:40 ` Alex Williamson
-1 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-28 12:40 UTC (permalink / raw)
To: Jike Song
Cc: Kirti Wankhede, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On Fri, 28 Oct 2016 15:33:58 +0800
Jike Song <jike.song@intel.com> wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> > Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> > about DMA_UNMAP.
> > Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> > Vendor driver should register notifer using these APIs.
> > Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> > mappings.
> >
> > Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> > Signed-off-by: Neo Jia <cjia@nvidia.com>
> > Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> > ---
> > drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> > drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> > include/linux/vfio.h | 11 +++++
> > 3 files changed, 163 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> > index 28b50ca14c52..ff05ac6b1e90 100644
> > --- a/drivers/vfio/vfio.c
> > +++ b/drivers/vfio/vfio.c
> > @@ -1891,6 +1891,79 @@ err_unpin_pages:
> > }
> > EXPORT_SYMBOL(vfio_unpin_pages);
> >
> > +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> > +{
> > + struct vfio_container *container;
> > + struct vfio_group *group;
> > + struct vfio_iommu_driver *driver;
> > + ssize_t ret;
> > +
> > + if (!dev || !nb)
> > + return -EINVAL;
> > +
> > + group = vfio_group_get_from_dev(dev);
> > + if (IS_ERR(group))
> > + return PTR_ERR(group);
> > +
> > + ret = vfio_group_add_container_user(group);
> > + if (ret)
> > + goto err_register_nb;
> > +
> > + container = group->container;
> > + down_read(&container->group_lock);
> > +
> > + driver = container->iommu_driver;
> > + if (likely(driver && driver->ops->register_notifier))
> > + ret = driver->ops->register_notifier(container->iommu_data, nb);
> > + else
> > + ret = -EINVAL;
> > +
> > + up_read(&container->group_lock);
> > + vfio_group_try_dissolve_container(group);
> > +
> > +err_register_nb:
> > + vfio_group_put(group);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(vfio_register_notifier);
> > +
> > +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> > +{
> > + struct vfio_container *container;
> > + struct vfio_group *group;
> > + struct vfio_iommu_driver *driver;
> > + ssize_t ret;
> > +
> > + if (!dev || !nb)
> > + return -EINVAL;
> > +
> > + group = vfio_group_get_from_dev(dev);
> > + if (IS_ERR(group))
> > + return PTR_ERR(group);
> > +
> > + ret = vfio_group_add_container_user(group);
> > + if (ret)
> > + goto err_unregister_nb;
> > +
> > + container = group->container;
> > + down_read(&container->group_lock);
> > +
> > + driver = container->iommu_driver;
> > + if (likely(driver && driver->ops->unregister_notifier))
> > + ret = driver->ops->unregister_notifier(container->iommu_data,
> > + nb);
> > + else
> > + ret = -EINVAL;
> > +
> > + up_read(&container->group_lock);
> > + vfio_group_try_dissolve_container(group);
> > +
> > +err_unregister_nb:
> > + vfio_group_put(group);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(vfio_unregister_notifier);
> > +
> > /**
> > * Module/class support
> > */
> > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> > index 5add11a147e1..a4bd331ac0fd 100644
> > --- a/drivers/vfio/vfio_iommu_type1.c
> > +++ b/drivers/vfio/vfio_iommu_type1.c
> > @@ -37,6 +37,7 @@
> > #include <linux/vfio.h>
> > #include <linux/workqueue.h>
> > #include <linux/mdev.h>
> > +#include <linux/notifier.h>
> >
> > #define DRIVER_VERSION "0.2"
> > #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> > @@ -59,6 +60,7 @@ struct vfio_iommu {
> > struct vfio_domain *external_domain; /* domain for external user */
> > struct mutex lock;
> > struct rb_root dma_list;
> > + struct blocking_notifier_head notifier;
> > bool v2;
> > bool nesting;
> > };
> > @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
> >
> > mutex_lock(&iommu->lock);
> >
> > - if (!iommu->external_domain) {
> > + /* Fail if notifier list is empty */
> > + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> > ret = -EINVAL;
> > goto pin_done;
> > }
> > @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> > return bitmap;
> > }
> >
> > +/*
> > + * This function finds pfn in domain->external_addr_space->pfn_list for given
> > + * iova range. If pfn exist, notify pfn to registered notifier list. On
> > + * receiving notifier callback, vendor driver should invalidate the mapping and
> > + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> > + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> > + * searching for next vfio_pfn in rb tree, start search from first node again.
> > + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> > + * from rb tree and so in next search vfio_pfn would be same as previous
> > + * vfio_pfn. In that case, exit from loop.
> > + */
> > +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> > + struct vfio_iommu_type1_dma_unmap *unmap)
> > +{
> > + struct vfio_domain *domain = iommu->external_domain;
> > + struct rb_node *n;
> > + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> > +
> > + do {
> > + prev_vpfn = vpfn;
> > + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> > +
> > + n = rb_first(&domain->external_addr_space->pfn_list);
> > +
> > + for (; n; n = rb_next(n), vpfn = NULL) {
> > + vpfn = rb_entry(n, struct vfio_pfn, node);
> > +
> > + if ((vpfn->iova >= unmap->iova) &&
> > + (vpfn->iova < unmap->iova + unmap->size))
> > + break;
> > + }
> > +
> > + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> > +
> > + /* Notify any listeners about DMA_UNMAP */
> > + if (vpfn)
> > + blocking_notifier_call_chain(&iommu->notifier,
> > + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> > + &vpfn->pfn);
>
> Hi Kirti,
>
> The information carried by notifier is only a pfn.
>
> Since your pin/unpin interfaces design, it's the vendor driver who should
> guarantee pin/unpin same times. To achieve that, the vendor driver must
> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> for multiple times.
>
> With the notifier carrying only a pfn, to find the iova by this pfn,
> the vendor driver must *also* keep a reverse-mapping. That's a bit
> too much.
>
> Since the vendor could also suffer from IOMMU-compatible problem,
> which means a local cache is always helpful, so I'd like to have the
> iova carried to the notifier.
>
> What'd you say?
I agree, the pfn is not unique, multiple guest pfns (iovas) might be
backed by the same host pfn. DMA_UNMAP calls are based on iova, the
notifier through to the vendor driver must be based on the same.
Thanks,
Alex
> > + } while (vpfn && (prev_vpfn != vpfn));
> > +
> > + WARN_ON(vpfn);
> > +}
> > +
> > static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
> > struct vfio_iommu_type1_dma_unmap *unmap)
> > {
> > @@ -844,6 +891,9 @@ unlock:
> > /* Report how much was unmapped */
> > unmap->size = unmapped;
> >
> > + if (unmapped && iommu->external_domain)
> > + vfio_notifier_call_chain(iommu, unmap);
> > +
> > return ret;
> > }
> >
> > @@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> > INIT_LIST_HEAD(&iommu->domain_list);
> > iommu->dma_list = RB_ROOT;
> > mutex_init(&iommu->lock);
> > + BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
> >
> > return iommu;
> > }
> > @@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
> > return -ENOTTY;
> > }
> >
> > +static int vfio_iommu_type1_register_notifier(void *iommu_data,
> > + struct notifier_block *nb)
> > +{
> > + struct vfio_iommu *iommu = iommu_data;
> > +
> > + return blocking_notifier_chain_register(&iommu->notifier, nb);
> > +}
> > +
> > +static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
> > + struct notifier_block *nb)
> > +{
> > + struct vfio_iommu *iommu = iommu_data;
> > +
> > + return blocking_notifier_chain_unregister(&iommu->notifier, nb);
> > +}
> > +
> > static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> > - .name = "vfio-iommu-type1",
> > - .owner = THIS_MODULE,
> > - .open = vfio_iommu_type1_open,
> > - .release = vfio_iommu_type1_release,
> > - .ioctl = vfio_iommu_type1_ioctl,
> > - .attach_group = vfio_iommu_type1_attach_group,
> > - .detach_group = vfio_iommu_type1_detach_group,
> > - .pin_pages = vfio_iommu_type1_pin_pages,
> > - .unpin_pages = vfio_iommu_type1_unpin_pages,
> > + .name = "vfio-iommu-type1",
> > + .owner = THIS_MODULE,
> > + .open = vfio_iommu_type1_open,
> > + .release = vfio_iommu_type1_release,
> > + .ioctl = vfio_iommu_type1_ioctl,
> > + .attach_group = vfio_iommu_type1_attach_group,
> > + .detach_group = vfio_iommu_type1_detach_group,
> > + .pin_pages = vfio_iommu_type1_pin_pages,
> > + .unpin_pages = vfio_iommu_type1_unpin_pages,
> > + .register_notifier = vfio_iommu_type1_register_notifier,
> > + .unregister_notifier = vfio_iommu_type1_unregister_notifier,
> > };
> >
> > static int __init vfio_iommu_type1_init(void)
> > diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> > index 0609a2052846..4c91ce8bfaeb 100644
> > --- a/include/linux/vfio.h
> > +++ b/include/linux/vfio.h
> > @@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
> > unsigned long *phys_pfn);
> > long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> > long npage);
> > + int (*register_notifier)(void *iommu_data,
> > + struct notifier_block *nb);
> > + int (*unregister_notifier)(void *iommu_data,
> > + struct notifier_block *nb);
> > };
> >
> > extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> > @@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> > extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> > long npage);
> >
> > +#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
> > +
> > +extern int vfio_register_notifier(struct device *dev,
> > + struct notifier_block *nb);
> > +
> > +extern int vfio_unregister_notifier(struct device *dev,
> > + struct notifier_block *nb);
> > /*
> > * IRQfd - generic
> > */
> >
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-28 12:40 ` Alex Williamson
0 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-28 12:40 UTC (permalink / raw)
To: Jike Song
Cc: Kirti Wankhede, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On Fri, 28 Oct 2016 15:33:58 +0800
Jike Song <jike.song@intel.com> wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> > Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> > about DMA_UNMAP.
> > Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> > Vendor driver should register notifer using these APIs.
> > Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> > mappings.
> >
> > Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> > Signed-off-by: Neo Jia <cjia@nvidia.com>
> > Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> > ---
> > drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> > drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> > include/linux/vfio.h | 11 +++++
> > 3 files changed, 163 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> > index 28b50ca14c52..ff05ac6b1e90 100644
> > --- a/drivers/vfio/vfio.c
> > +++ b/drivers/vfio/vfio.c
> > @@ -1891,6 +1891,79 @@ err_unpin_pages:
> > }
> > EXPORT_SYMBOL(vfio_unpin_pages);
> >
> > +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> > +{
> > + struct vfio_container *container;
> > + struct vfio_group *group;
> > + struct vfio_iommu_driver *driver;
> > + ssize_t ret;
> > +
> > + if (!dev || !nb)
> > + return -EINVAL;
> > +
> > + group = vfio_group_get_from_dev(dev);
> > + if (IS_ERR(group))
> > + return PTR_ERR(group);
> > +
> > + ret = vfio_group_add_container_user(group);
> > + if (ret)
> > + goto err_register_nb;
> > +
> > + container = group->container;
> > + down_read(&container->group_lock);
> > +
> > + driver = container->iommu_driver;
> > + if (likely(driver && driver->ops->register_notifier))
> > + ret = driver->ops->register_notifier(container->iommu_data, nb);
> > + else
> > + ret = -EINVAL;
> > +
> > + up_read(&container->group_lock);
> > + vfio_group_try_dissolve_container(group);
> > +
> > +err_register_nb:
> > + vfio_group_put(group);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(vfio_register_notifier);
> > +
> > +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> > +{
> > + struct vfio_container *container;
> > + struct vfio_group *group;
> > + struct vfio_iommu_driver *driver;
> > + ssize_t ret;
> > +
> > + if (!dev || !nb)
> > + return -EINVAL;
> > +
> > + group = vfio_group_get_from_dev(dev);
> > + if (IS_ERR(group))
> > + return PTR_ERR(group);
> > +
> > + ret = vfio_group_add_container_user(group);
> > + if (ret)
> > + goto err_unregister_nb;
> > +
> > + container = group->container;
> > + down_read(&container->group_lock);
> > +
> > + driver = container->iommu_driver;
> > + if (likely(driver && driver->ops->unregister_notifier))
> > + ret = driver->ops->unregister_notifier(container->iommu_data,
> > + nb);
> > + else
> > + ret = -EINVAL;
> > +
> > + up_read(&container->group_lock);
> > + vfio_group_try_dissolve_container(group);
> > +
> > +err_unregister_nb:
> > + vfio_group_put(group);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(vfio_unregister_notifier);
> > +
> > /**
> > * Module/class support
> > */
> > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> > index 5add11a147e1..a4bd331ac0fd 100644
> > --- a/drivers/vfio/vfio_iommu_type1.c
> > +++ b/drivers/vfio/vfio_iommu_type1.c
> > @@ -37,6 +37,7 @@
> > #include <linux/vfio.h>
> > #include <linux/workqueue.h>
> > #include <linux/mdev.h>
> > +#include <linux/notifier.h>
> >
> > #define DRIVER_VERSION "0.2"
> > #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> > @@ -59,6 +60,7 @@ struct vfio_iommu {
> > struct vfio_domain *external_domain; /* domain for external user */
> > struct mutex lock;
> > struct rb_root dma_list;
> > + struct blocking_notifier_head notifier;
> > bool v2;
> > bool nesting;
> > };
> > @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
> >
> > mutex_lock(&iommu->lock);
> >
> > - if (!iommu->external_domain) {
> > + /* Fail if notifier list is empty */
> > + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> > ret = -EINVAL;
> > goto pin_done;
> > }
> > @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> > return bitmap;
> > }
> >
> > +/*
> > + * This function finds pfn in domain->external_addr_space->pfn_list for given
> > + * iova range. If pfn exist, notify pfn to registered notifier list. On
> > + * receiving notifier callback, vendor driver should invalidate the mapping and
> > + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> > + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> > + * searching for next vfio_pfn in rb tree, start search from first node again.
> > + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> > + * from rb tree and so in next search vfio_pfn would be same as previous
> > + * vfio_pfn. In that case, exit from loop.
> > + */
> > +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> > + struct vfio_iommu_type1_dma_unmap *unmap)
> > +{
> > + struct vfio_domain *domain = iommu->external_domain;
> > + struct rb_node *n;
> > + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> > +
> > + do {
> > + prev_vpfn = vpfn;
> > + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> > +
> > + n = rb_first(&domain->external_addr_space->pfn_list);
> > +
> > + for (; n; n = rb_next(n), vpfn = NULL) {
> > + vpfn = rb_entry(n, struct vfio_pfn, node);
> > +
> > + if ((vpfn->iova >= unmap->iova) &&
> > + (vpfn->iova < unmap->iova + unmap->size))
> > + break;
> > + }
> > +
> > + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> > +
> > + /* Notify any listeners about DMA_UNMAP */
> > + if (vpfn)
> > + blocking_notifier_call_chain(&iommu->notifier,
> > + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> > + &vpfn->pfn);
>
> Hi Kirti,
>
> The information carried by notifier is only a pfn.
>
> Since your pin/unpin interfaces design, it's the vendor driver who should
> guarantee pin/unpin same times. To achieve that, the vendor driver must
> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> for multiple times.
>
> With the notifier carrying only a pfn, to find the iova by this pfn,
> the vendor driver must *also* keep a reverse-mapping. That's a bit
> too much.
>
> Since the vendor could also suffer from IOMMU-compatible problem,
> which means a local cache is always helpful, so I'd like to have the
> iova carried to the notifier.
>
> What'd you say?
I agree, the pfn is not unique, multiple guest pfns (iovas) might be
backed by the same host pfn. DMA_UNMAP calls are based on iova, the
notifier through to the vendor driver must be based on the same.
Thanks,
Alex
> > + } while (vpfn && (prev_vpfn != vpfn));
> > +
> > + WARN_ON(vpfn);
> > +}
> > +
> > static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
> > struct vfio_iommu_type1_dma_unmap *unmap)
> > {
> > @@ -844,6 +891,9 @@ unlock:
> > /* Report how much was unmapped */
> > unmap->size = unmapped;
> >
> > + if (unmapped && iommu->external_domain)
> > + vfio_notifier_call_chain(iommu, unmap);
> > +
> > return ret;
> > }
> >
> > @@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> > INIT_LIST_HEAD(&iommu->domain_list);
> > iommu->dma_list = RB_ROOT;
> > mutex_init(&iommu->lock);
> > + BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
> >
> > return iommu;
> > }
> > @@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
> > return -ENOTTY;
> > }
> >
> > +static int vfio_iommu_type1_register_notifier(void *iommu_data,
> > + struct notifier_block *nb)
> > +{
> > + struct vfio_iommu *iommu = iommu_data;
> > +
> > + return blocking_notifier_chain_register(&iommu->notifier, nb);
> > +}
> > +
> > +static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
> > + struct notifier_block *nb)
> > +{
> > + struct vfio_iommu *iommu = iommu_data;
> > +
> > + return blocking_notifier_chain_unregister(&iommu->notifier, nb);
> > +}
> > +
> > static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> > - .name = "vfio-iommu-type1",
> > - .owner = THIS_MODULE,
> > - .open = vfio_iommu_type1_open,
> > - .release = vfio_iommu_type1_release,
> > - .ioctl = vfio_iommu_type1_ioctl,
> > - .attach_group = vfio_iommu_type1_attach_group,
> > - .detach_group = vfio_iommu_type1_detach_group,
> > - .pin_pages = vfio_iommu_type1_pin_pages,
> > - .unpin_pages = vfio_iommu_type1_unpin_pages,
> > + .name = "vfio-iommu-type1",
> > + .owner = THIS_MODULE,
> > + .open = vfio_iommu_type1_open,
> > + .release = vfio_iommu_type1_release,
> > + .ioctl = vfio_iommu_type1_ioctl,
> > + .attach_group = vfio_iommu_type1_attach_group,
> > + .detach_group = vfio_iommu_type1_detach_group,
> > + .pin_pages = vfio_iommu_type1_pin_pages,
> > + .unpin_pages = vfio_iommu_type1_unpin_pages,
> > + .register_notifier = vfio_iommu_type1_register_notifier,
> > + .unregister_notifier = vfio_iommu_type1_unregister_notifier,
> > };
> >
> > static int __init vfio_iommu_type1_init(void)
> > diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> > index 0609a2052846..4c91ce8bfaeb 100644
> > --- a/include/linux/vfio.h
> > +++ b/include/linux/vfio.h
> > @@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
> > unsigned long *phys_pfn);
> > long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> > long npage);
> > + int (*register_notifier)(void *iommu_data,
> > + struct notifier_block *nb);
> > + int (*unregister_notifier)(void *iommu_data,
> > + struct notifier_block *nb);
> > };
> >
> > extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> > @@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> > extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> > long npage);
> >
> > +#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
> > +
> > +extern int vfio_register_notifier(struct device *dev,
> > + struct notifier_block *nb);
> > +
> > +extern int vfio_unregister_notifier(struct device *dev,
> > + struct notifier_block *nb);
> > /*
> > * IRQfd - generic
> > */
> >
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-28 12:40 ` [Qemu-devel] " Alex Williamson
@ 2016-10-28 20:02 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-28 20:02 UTC (permalink / raw)
To: Alex Williamson, Jike Song
Cc: pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian, bjsdjshi,
linux-kernel
On 10/28/2016 6:10 PM, Alex Williamson wrote:
> On Fri, 28 Oct 2016 15:33:58 +0800
> Jike Song <jike.song@intel.com> wrote:
>
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
>>> about DMA_UNMAP.
>>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
>>> Vendor driver should register notifer using these APIs.
>>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
>>> mappings.
>>>
>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
>>> ---
>>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
>>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
>>> include/linux/vfio.h | 11 +++++
>>> 3 files changed, 163 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
>>> index 28b50ca14c52..ff05ac6b1e90 100644
>>> --- a/drivers/vfio/vfio.c
>>> +++ b/drivers/vfio/vfio.c
>>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
>>> }
>>> EXPORT_SYMBOL(vfio_unpin_pages);
>>>
>>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
>>> +{
>>> + struct vfio_container *container;
>>> + struct vfio_group *group;
>>> + struct vfio_iommu_driver *driver;
>>> + ssize_t ret;
>>> +
>>> + if (!dev || !nb)
>>> + return -EINVAL;
>>> +
>>> + group = vfio_group_get_from_dev(dev);
>>> + if (IS_ERR(group))
>>> + return PTR_ERR(group);
>>> +
>>> + ret = vfio_group_add_container_user(group);
>>> + if (ret)
>>> + goto err_register_nb;
>>> +
>>> + container = group->container;
>>> + down_read(&container->group_lock);
>>> +
>>> + driver = container->iommu_driver;
>>> + if (likely(driver && driver->ops->register_notifier))
>>> + ret = driver->ops->register_notifier(container->iommu_data, nb);
>>> + else
>>> + ret = -EINVAL;
>>> +
>>> + up_read(&container->group_lock);
>>> + vfio_group_try_dissolve_container(group);
>>> +
>>> +err_register_nb:
>>> + vfio_group_put(group);
>>> + return ret;
>>> +}
>>> +EXPORT_SYMBOL(vfio_register_notifier);
>>> +
>>> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
>>> +{
>>> + struct vfio_container *container;
>>> + struct vfio_group *group;
>>> + struct vfio_iommu_driver *driver;
>>> + ssize_t ret;
>>> +
>>> + if (!dev || !nb)
>>> + return -EINVAL;
>>> +
>>> + group = vfio_group_get_from_dev(dev);
>>> + if (IS_ERR(group))
>>> + return PTR_ERR(group);
>>> +
>>> + ret = vfio_group_add_container_user(group);
>>> + if (ret)
>>> + goto err_unregister_nb;
>>> +
>>> + container = group->container;
>>> + down_read(&container->group_lock);
>>> +
>>> + driver = container->iommu_driver;
>>> + if (likely(driver && driver->ops->unregister_notifier))
>>> + ret = driver->ops->unregister_notifier(container->iommu_data,
>>> + nb);
>>> + else
>>> + ret = -EINVAL;
>>> +
>>> + up_read(&container->group_lock);
>>> + vfio_group_try_dissolve_container(group);
>>> +
>>> +err_unregister_nb:
>>> + vfio_group_put(group);
>>> + return ret;
>>> +}
>>> +EXPORT_SYMBOL(vfio_unregister_notifier);
>>> +
>>> /**
>>> * Module/class support
>>> */
>>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>>> index 5add11a147e1..a4bd331ac0fd 100644
>>> --- a/drivers/vfio/vfio_iommu_type1.c
>>> +++ b/drivers/vfio/vfio_iommu_type1.c
>>> @@ -37,6 +37,7 @@
>>> #include <linux/vfio.h>
>>> #include <linux/workqueue.h>
>>> #include <linux/mdev.h>
>>> +#include <linux/notifier.h>
>>>
>>> #define DRIVER_VERSION "0.2"
>>> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
>>> @@ -59,6 +60,7 @@ struct vfio_iommu {
>>> struct vfio_domain *external_domain; /* domain for external user */
>>> struct mutex lock;
>>> struct rb_root dma_list;
>>> + struct blocking_notifier_head notifier;
>>> bool v2;
>>> bool nesting;
>>> };
>>> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
>>>
>>> mutex_lock(&iommu->lock);
>>>
>>> - if (!iommu->external_domain) {
>>> + /* Fail if notifier list is empty */
>>> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
>>> ret = -EINVAL;
>>> goto pin_done;
>>> }
>>> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
>>> return bitmap;
>>> }
>>>
>>> +/*
>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>>> + * from rb tree and so in next search vfio_pfn would be same as previous
>>> + * vfio_pfn. In that case, exit from loop.
>>> + */
>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>>> + struct vfio_iommu_type1_dma_unmap *unmap)
>>> +{
>>> + struct vfio_domain *domain = iommu->external_domain;
>>> + struct rb_node *n;
>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>>> +
>>> + do {
>>> + prev_vpfn = vpfn;
>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>>> +
>>> + n = rb_first(&domain->external_addr_space->pfn_list);
>>> +
>>> + for (; n; n = rb_next(n), vpfn = NULL) {
>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>>> +
>>> + if ((vpfn->iova >= unmap->iova) &&
>>> + (vpfn->iova < unmap->iova + unmap->size))
>>> + break;
>>> + }
>>> +
>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>>> +
>>> + /* Notify any listeners about DMA_UNMAP */
>>> + if (vpfn)
>>> + blocking_notifier_call_chain(&iommu->notifier,
>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>> + &vpfn->pfn);
>>
>> Hi Kirti,
>>
>> The information carried by notifier is only a pfn.
>>
>> Since your pin/unpin interfaces design, it's the vendor driver who should
>> guarantee pin/unpin same times. To achieve that, the vendor driver must
>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
>> for multiple times.
>>
>> With the notifier carrying only a pfn, to find the iova by this pfn,
>> the vendor driver must *also* keep a reverse-mapping. That's a bit
>> too much.
>>
>> Since the vendor could also suffer from IOMMU-compatible problem,
>> which means a local cache is always helpful, so I'd like to have the
>> iova carried to the notifier.
>>
>> What'd you say?
>
> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> notifier through to the vendor driver must be based on the same.
Host pfn should be unique, right?
Kirti.
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-28 20:02 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-28 20:02 UTC (permalink / raw)
To: Alex Williamson, Jike Song
Cc: pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian, bjsdjshi,
linux-kernel
On 10/28/2016 6:10 PM, Alex Williamson wrote:
> On Fri, 28 Oct 2016 15:33:58 +0800
> Jike Song <jike.song@intel.com> wrote:
>
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
>>> about DMA_UNMAP.
>>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
>>> Vendor driver should register notifer using these APIs.
>>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
>>> mappings.
>>>
>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
>>> ---
>>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
>>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
>>> include/linux/vfio.h | 11 +++++
>>> 3 files changed, 163 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
>>> index 28b50ca14c52..ff05ac6b1e90 100644
>>> --- a/drivers/vfio/vfio.c
>>> +++ b/drivers/vfio/vfio.c
>>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
>>> }
>>> EXPORT_SYMBOL(vfio_unpin_pages);
>>>
>>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
>>> +{
>>> + struct vfio_container *container;
>>> + struct vfio_group *group;
>>> + struct vfio_iommu_driver *driver;
>>> + ssize_t ret;
>>> +
>>> + if (!dev || !nb)
>>> + return -EINVAL;
>>> +
>>> + group = vfio_group_get_from_dev(dev);
>>> + if (IS_ERR(group))
>>> + return PTR_ERR(group);
>>> +
>>> + ret = vfio_group_add_container_user(group);
>>> + if (ret)
>>> + goto err_register_nb;
>>> +
>>> + container = group->container;
>>> + down_read(&container->group_lock);
>>> +
>>> + driver = container->iommu_driver;
>>> + if (likely(driver && driver->ops->register_notifier))
>>> + ret = driver->ops->register_notifier(container->iommu_data, nb);
>>> + else
>>> + ret = -EINVAL;
>>> +
>>> + up_read(&container->group_lock);
>>> + vfio_group_try_dissolve_container(group);
>>> +
>>> +err_register_nb:
>>> + vfio_group_put(group);
>>> + return ret;
>>> +}
>>> +EXPORT_SYMBOL(vfio_register_notifier);
>>> +
>>> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
>>> +{
>>> + struct vfio_container *container;
>>> + struct vfio_group *group;
>>> + struct vfio_iommu_driver *driver;
>>> + ssize_t ret;
>>> +
>>> + if (!dev || !nb)
>>> + return -EINVAL;
>>> +
>>> + group = vfio_group_get_from_dev(dev);
>>> + if (IS_ERR(group))
>>> + return PTR_ERR(group);
>>> +
>>> + ret = vfio_group_add_container_user(group);
>>> + if (ret)
>>> + goto err_unregister_nb;
>>> +
>>> + container = group->container;
>>> + down_read(&container->group_lock);
>>> +
>>> + driver = container->iommu_driver;
>>> + if (likely(driver && driver->ops->unregister_notifier))
>>> + ret = driver->ops->unregister_notifier(container->iommu_data,
>>> + nb);
>>> + else
>>> + ret = -EINVAL;
>>> +
>>> + up_read(&container->group_lock);
>>> + vfio_group_try_dissolve_container(group);
>>> +
>>> +err_unregister_nb:
>>> + vfio_group_put(group);
>>> + return ret;
>>> +}
>>> +EXPORT_SYMBOL(vfio_unregister_notifier);
>>> +
>>> /**
>>> * Module/class support
>>> */
>>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>>> index 5add11a147e1..a4bd331ac0fd 100644
>>> --- a/drivers/vfio/vfio_iommu_type1.c
>>> +++ b/drivers/vfio/vfio_iommu_type1.c
>>> @@ -37,6 +37,7 @@
>>> #include <linux/vfio.h>
>>> #include <linux/workqueue.h>
>>> #include <linux/mdev.h>
>>> +#include <linux/notifier.h>
>>>
>>> #define DRIVER_VERSION "0.2"
>>> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
>>> @@ -59,6 +60,7 @@ struct vfio_iommu {
>>> struct vfio_domain *external_domain; /* domain for external user */
>>> struct mutex lock;
>>> struct rb_root dma_list;
>>> + struct blocking_notifier_head notifier;
>>> bool v2;
>>> bool nesting;
>>> };
>>> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
>>>
>>> mutex_lock(&iommu->lock);
>>>
>>> - if (!iommu->external_domain) {
>>> + /* Fail if notifier list is empty */
>>> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
>>> ret = -EINVAL;
>>> goto pin_done;
>>> }
>>> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
>>> return bitmap;
>>> }
>>>
>>> +/*
>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>>> + * from rb tree and so in next search vfio_pfn would be same as previous
>>> + * vfio_pfn. In that case, exit from loop.
>>> + */
>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>>> + struct vfio_iommu_type1_dma_unmap *unmap)
>>> +{
>>> + struct vfio_domain *domain = iommu->external_domain;
>>> + struct rb_node *n;
>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>>> +
>>> + do {
>>> + prev_vpfn = vpfn;
>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>>> +
>>> + n = rb_first(&domain->external_addr_space->pfn_list);
>>> +
>>> + for (; n; n = rb_next(n), vpfn = NULL) {
>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>>> +
>>> + if ((vpfn->iova >= unmap->iova) &&
>>> + (vpfn->iova < unmap->iova + unmap->size))
>>> + break;
>>> + }
>>> +
>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>>> +
>>> + /* Notify any listeners about DMA_UNMAP */
>>> + if (vpfn)
>>> + blocking_notifier_call_chain(&iommu->notifier,
>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>> + &vpfn->pfn);
>>
>> Hi Kirti,
>>
>> The information carried by notifier is only a pfn.
>>
>> Since your pin/unpin interfaces design, it's the vendor driver who should
>> guarantee pin/unpin same times. To achieve that, the vendor driver must
>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
>> for multiple times.
>>
>> With the notifier carrying only a pfn, to find the iova by this pfn,
>> the vendor driver must *also* keep a reverse-mapping. That's a bit
>> too much.
>>
>> Since the vendor could also suffer from IOMMU-compatible problem,
>> which means a local cache is always helpful, so I'd like to have the
>> iova carried to the notifier.
>>
>> What'd you say?
>
> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> notifier through to the vendor driver must be based on the same.
Host pfn should be unique, right?
Kirti.
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-28 20:02 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-28 20:33 ` Alex Williamson
-1 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-28 20:33 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Jike Song, pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian,
bjsdjshi, linux-kernel
On Sat, 29 Oct 2016 01:32:35 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> > On Fri, 28 Oct 2016 15:33:58 +0800
> > Jike Song <jike.song@intel.com> wrote:
> >
> >> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> >>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> >>> about DMA_UNMAP.
> >>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> >>> Vendor driver should register notifer using these APIs.
> >>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> >>> mappings.
> >>>
> >>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> >>> Signed-off-by: Neo Jia <cjia@nvidia.com>
> >>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> >>> ---
> >>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> >>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> >>> include/linux/vfio.h | 11 +++++
> >>> 3 files changed, 163 insertions(+), 10 deletions(-)
> >>>
> >>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> >>> index 28b50ca14c52..ff05ac6b1e90 100644
> >>> --- a/drivers/vfio/vfio.c
> >>> +++ b/drivers/vfio/vfio.c
> >>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
> >>> }
> >>> EXPORT_SYMBOL(vfio_unpin_pages);
> >>>
> >>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> >>> +{
> >>> + struct vfio_container *container;
> >>> + struct vfio_group *group;
> >>> + struct vfio_iommu_driver *driver;
> >>> + ssize_t ret;
> >>> +
> >>> + if (!dev || !nb)
> >>> + return -EINVAL;
> >>> +
> >>> + group = vfio_group_get_from_dev(dev);
> >>> + if (IS_ERR(group))
> >>> + return PTR_ERR(group);
> >>> +
> >>> + ret = vfio_group_add_container_user(group);
> >>> + if (ret)
> >>> + goto err_register_nb;
> >>> +
> >>> + container = group->container;
> >>> + down_read(&container->group_lock);
> >>> +
> >>> + driver = container->iommu_driver;
> >>> + if (likely(driver && driver->ops->register_notifier))
> >>> + ret = driver->ops->register_notifier(container->iommu_data, nb);
> >>> + else
> >>> + ret = -EINVAL;
> >>> +
> >>> + up_read(&container->group_lock);
> >>> + vfio_group_try_dissolve_container(group);
> >>> +
> >>> +err_register_nb:
> >>> + vfio_group_put(group);
> >>> + return ret;
> >>> +}
> >>> +EXPORT_SYMBOL(vfio_register_notifier);
> >>> +
> >>> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> >>> +{
> >>> + struct vfio_container *container;
> >>> + struct vfio_group *group;
> >>> + struct vfio_iommu_driver *driver;
> >>> + ssize_t ret;
> >>> +
> >>> + if (!dev || !nb)
> >>> + return -EINVAL;
> >>> +
> >>> + group = vfio_group_get_from_dev(dev);
> >>> + if (IS_ERR(group))
> >>> + return PTR_ERR(group);
> >>> +
> >>> + ret = vfio_group_add_container_user(group);
> >>> + if (ret)
> >>> + goto err_unregister_nb;
> >>> +
> >>> + container = group->container;
> >>> + down_read(&container->group_lock);
> >>> +
> >>> + driver = container->iommu_driver;
> >>> + if (likely(driver && driver->ops->unregister_notifier))
> >>> + ret = driver->ops->unregister_notifier(container->iommu_data,
> >>> + nb);
> >>> + else
> >>> + ret = -EINVAL;
> >>> +
> >>> + up_read(&container->group_lock);
> >>> + vfio_group_try_dissolve_container(group);
> >>> +
> >>> +err_unregister_nb:
> >>> + vfio_group_put(group);
> >>> + return ret;
> >>> +}
> >>> +EXPORT_SYMBOL(vfio_unregister_notifier);
> >>> +
> >>> /**
> >>> * Module/class support
> >>> */
> >>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> >>> index 5add11a147e1..a4bd331ac0fd 100644
> >>> --- a/drivers/vfio/vfio_iommu_type1.c
> >>> +++ b/drivers/vfio/vfio_iommu_type1.c
> >>> @@ -37,6 +37,7 @@
> >>> #include <linux/vfio.h>
> >>> #include <linux/workqueue.h>
> >>> #include <linux/mdev.h>
> >>> +#include <linux/notifier.h>
> >>>
> >>> #define DRIVER_VERSION "0.2"
> >>> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> >>> @@ -59,6 +60,7 @@ struct vfio_iommu {
> >>> struct vfio_domain *external_domain; /* domain for external user */
> >>> struct mutex lock;
> >>> struct rb_root dma_list;
> >>> + struct blocking_notifier_head notifier;
> >>> bool v2;
> >>> bool nesting;
> >>> };
> >>> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
> >>>
> >>> mutex_lock(&iommu->lock);
> >>>
> >>> - if (!iommu->external_domain) {
> >>> + /* Fail if notifier list is empty */
> >>> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> >>> ret = -EINVAL;
> >>> goto pin_done;
> >>> }
> >>> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> >>> return bitmap;
> >>> }
> >>>
> >>> +/*
> >>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> >>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> >>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> >>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> >>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> >>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> >>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> >>> + * from rb tree and so in next search vfio_pfn would be same as previous
> >>> + * vfio_pfn. In that case, exit from loop.
> >>> + */
> >>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> >>> + struct vfio_iommu_type1_dma_unmap *unmap)
> >>> +{
> >>> + struct vfio_domain *domain = iommu->external_domain;
> >>> + struct rb_node *n;
> >>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> >>> +
> >>> + do {
> >>> + prev_vpfn = vpfn;
> >>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> >>> +
> >>> + n = rb_first(&domain->external_addr_space->pfn_list);
> >>> +
> >>> + for (; n; n = rb_next(n), vpfn = NULL) {
> >>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> >>> +
> >>> + if ((vpfn->iova >= unmap->iova) &&
> >>> + (vpfn->iova < unmap->iova + unmap->size))
> >>> + break;
> >>> + }
> >>> +
> >>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> >>> +
> >>> + /* Notify any listeners about DMA_UNMAP */
> >>> + if (vpfn)
> >>> + blocking_notifier_call_chain(&iommu->notifier,
> >>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>> + &vpfn->pfn);
> >>
> >> Hi Kirti,
> >>
> >> The information carried by notifier is only a pfn.
> >>
> >> Since your pin/unpin interfaces design, it's the vendor driver who should
> >> guarantee pin/unpin same times. To achieve that, the vendor driver must
> >> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> >> for multiple times.
> >>
> >> With the notifier carrying only a pfn, to find the iova by this pfn,
> >> the vendor driver must *also* keep a reverse-mapping. That's a bit
> >> too much.
> >>
> >> Since the vendor could also suffer from IOMMU-compatible problem,
> >> which means a local cache is always helpful, so I'd like to have the
> >> iova carried to the notifier.
> >>
> >> What'd you say?
> >
> > I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> > backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> > notifier through to the vendor driver must be based on the same.
>
> Host pfn should be unique, right?
Let's say a user does a malloc of a single page and does 100 calls to
MAP_DMA populating 100 pages of IOVA space all backed by the same
malloc'd page. This is valid, I have unit tests that do essentially
this. Those will all have the same pfn. The user then does an
UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
everything matching that pfn? Of course not, they only unmapped that
one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
driver MUST therefore also work based on IOVA. This is not an academic
problem, address space aliases exist in real VMs, imagine a virtual
IOMMU. Thanks,
Alex
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-28 20:33 ` Alex Williamson
0 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-28 20:33 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Jike Song, pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian,
bjsdjshi, linux-kernel
On Sat, 29 Oct 2016 01:32:35 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> > On Fri, 28 Oct 2016 15:33:58 +0800
> > Jike Song <jike.song@intel.com> wrote:
> >
> >> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> >>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> >>> about DMA_UNMAP.
> >>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> >>> Vendor driver should register notifer using these APIs.
> >>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> >>> mappings.
> >>>
> >>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> >>> Signed-off-by: Neo Jia <cjia@nvidia.com>
> >>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> >>> ---
> >>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> >>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> >>> include/linux/vfio.h | 11 +++++
> >>> 3 files changed, 163 insertions(+), 10 deletions(-)
> >>>
> >>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> >>> index 28b50ca14c52..ff05ac6b1e90 100644
> >>> --- a/drivers/vfio/vfio.c
> >>> +++ b/drivers/vfio/vfio.c
> >>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
> >>> }
> >>> EXPORT_SYMBOL(vfio_unpin_pages);
> >>>
> >>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> >>> +{
> >>> + struct vfio_container *container;
> >>> + struct vfio_group *group;
> >>> + struct vfio_iommu_driver *driver;
> >>> + ssize_t ret;
> >>> +
> >>> + if (!dev || !nb)
> >>> + return -EINVAL;
> >>> +
> >>> + group = vfio_group_get_from_dev(dev);
> >>> + if (IS_ERR(group))
> >>> + return PTR_ERR(group);
> >>> +
> >>> + ret = vfio_group_add_container_user(group);
> >>> + if (ret)
> >>> + goto err_register_nb;
> >>> +
> >>> + container = group->container;
> >>> + down_read(&container->group_lock);
> >>> +
> >>> + driver = container->iommu_driver;
> >>> + if (likely(driver && driver->ops->register_notifier))
> >>> + ret = driver->ops->register_notifier(container->iommu_data, nb);
> >>> + else
> >>> + ret = -EINVAL;
> >>> +
> >>> + up_read(&container->group_lock);
> >>> + vfio_group_try_dissolve_container(group);
> >>> +
> >>> +err_register_nb:
> >>> + vfio_group_put(group);
> >>> + return ret;
> >>> +}
> >>> +EXPORT_SYMBOL(vfio_register_notifier);
> >>> +
> >>> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> >>> +{
> >>> + struct vfio_container *container;
> >>> + struct vfio_group *group;
> >>> + struct vfio_iommu_driver *driver;
> >>> + ssize_t ret;
> >>> +
> >>> + if (!dev || !nb)
> >>> + return -EINVAL;
> >>> +
> >>> + group = vfio_group_get_from_dev(dev);
> >>> + if (IS_ERR(group))
> >>> + return PTR_ERR(group);
> >>> +
> >>> + ret = vfio_group_add_container_user(group);
> >>> + if (ret)
> >>> + goto err_unregister_nb;
> >>> +
> >>> + container = group->container;
> >>> + down_read(&container->group_lock);
> >>> +
> >>> + driver = container->iommu_driver;
> >>> + if (likely(driver && driver->ops->unregister_notifier))
> >>> + ret = driver->ops->unregister_notifier(container->iommu_data,
> >>> + nb);
> >>> + else
> >>> + ret = -EINVAL;
> >>> +
> >>> + up_read(&container->group_lock);
> >>> + vfio_group_try_dissolve_container(group);
> >>> +
> >>> +err_unregister_nb:
> >>> + vfio_group_put(group);
> >>> + return ret;
> >>> +}
> >>> +EXPORT_SYMBOL(vfio_unregister_notifier);
> >>> +
> >>> /**
> >>> * Module/class support
> >>> */
> >>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> >>> index 5add11a147e1..a4bd331ac0fd 100644
> >>> --- a/drivers/vfio/vfio_iommu_type1.c
> >>> +++ b/drivers/vfio/vfio_iommu_type1.c
> >>> @@ -37,6 +37,7 @@
> >>> #include <linux/vfio.h>
> >>> #include <linux/workqueue.h>
> >>> #include <linux/mdev.h>
> >>> +#include <linux/notifier.h>
> >>>
> >>> #define DRIVER_VERSION "0.2"
> >>> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> >>> @@ -59,6 +60,7 @@ struct vfio_iommu {
> >>> struct vfio_domain *external_domain; /* domain for external user */
> >>> struct mutex lock;
> >>> struct rb_root dma_list;
> >>> + struct blocking_notifier_head notifier;
> >>> bool v2;
> >>> bool nesting;
> >>> };
> >>> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
> >>>
> >>> mutex_lock(&iommu->lock);
> >>>
> >>> - if (!iommu->external_domain) {
> >>> + /* Fail if notifier list is empty */
> >>> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> >>> ret = -EINVAL;
> >>> goto pin_done;
> >>> }
> >>> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> >>> return bitmap;
> >>> }
> >>>
> >>> +/*
> >>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> >>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> >>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> >>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> >>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> >>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> >>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> >>> + * from rb tree and so in next search vfio_pfn would be same as previous
> >>> + * vfio_pfn. In that case, exit from loop.
> >>> + */
> >>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> >>> + struct vfio_iommu_type1_dma_unmap *unmap)
> >>> +{
> >>> + struct vfio_domain *domain = iommu->external_domain;
> >>> + struct rb_node *n;
> >>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> >>> +
> >>> + do {
> >>> + prev_vpfn = vpfn;
> >>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> >>> +
> >>> + n = rb_first(&domain->external_addr_space->pfn_list);
> >>> +
> >>> + for (; n; n = rb_next(n), vpfn = NULL) {
> >>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> >>> +
> >>> + if ((vpfn->iova >= unmap->iova) &&
> >>> + (vpfn->iova < unmap->iova + unmap->size))
> >>> + break;
> >>> + }
> >>> +
> >>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> >>> +
> >>> + /* Notify any listeners about DMA_UNMAP */
> >>> + if (vpfn)
> >>> + blocking_notifier_call_chain(&iommu->notifier,
> >>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>> + &vpfn->pfn);
> >>
> >> Hi Kirti,
> >>
> >> The information carried by notifier is only a pfn.
> >>
> >> Since your pin/unpin interfaces design, it's the vendor driver who should
> >> guarantee pin/unpin same times. To achieve that, the vendor driver must
> >> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> >> for multiple times.
> >>
> >> With the notifier carrying only a pfn, to find the iova by this pfn,
> >> the vendor driver must *also* keep a reverse-mapping. That's a bit
> >> too much.
> >>
> >> Since the vendor could also suffer from IOMMU-compatible problem,
> >> which means a local cache is always helpful, so I'd like to have the
> >> iova carried to the notifier.
> >>
> >> What'd you say?
> >
> > I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> > backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> > notifier through to the vendor driver must be based on the same.
>
> Host pfn should be unique, right?
Let's say a user does a malloc of a single page and does 100 calls to
MAP_DMA populating 100 pages of IOVA space all backed by the same
malloc'd page. This is valid, I have unit tests that do essentially
this. Those will all have the same pfn. The user then does an
UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
everything matching that pfn? Of course not, they only unmapped that
one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
driver MUST therefore also work based on IOVA. This is not an academic
problem, address space aliases exist in real VMs, imagine a virtual
IOMMU. Thanks,
Alex
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 01/19] vfio: Mediated device Core driver
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-29 4:30 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-29 4:30 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
> +{
> + int ret;
> + struct parent_device *parent;
> +
> + /* check for mandatory ops */
> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
> + return -EINVAL;
> +
> + dev = get_device(dev);
> + if (!dev)
> + return -EINVAL;
> +
> + mutex_lock(&parent_list_lock);
> +
> + /* Check for duplicate */
> + parent = __find_parent_device(dev);
> + if (parent) {
> + ret = -EEXIST;
> + goto add_dev_err;
> + }
> +
> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
> + if (!parent) {
> + ret = -ENOMEM;
> + goto add_dev_err;
> + }
> +
> + kref_init(&parent->ref);
> + mutex_init(&parent->lock);
> +
> + parent->dev = dev;
> + parent->ops = ops;
> +
> + ret = parent_create_sysfs_files(parent);
> + if (ret) {
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> + return ret;
> + }
> +
> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
> + if (ret)
> + dev_warn(dev, "Failed to create compatibility class link\n");
> +
Hi Kirti,
Like I replied to previous version:
http://www.spinics.net/lists/kvm/msg139331.html
You can always check if mdev_bus_compat_class already registered
here, and register it if not yet. Same logic should be adopted to
mdev_init.
Current implementation will simply panic if configured as builtin,
which is rare but far from impossible.
--
Thanks,
Jike
> + list_add(&parent->next, &parent_list);
> + mutex_unlock(&parent_list_lock);
> +
> + dev_info(dev, "MDEV: Registered\n");
> + return 0;
> +
> +add_dev_err:
> + mutex_unlock(&parent_list_lock);
> + put_device(dev);
> + return ret;
> +}
> +EXPORT_SYMBOL(mdev_register_device);
> +
> +/*
> + * mdev_unregister_device : Unregister a parent device
> + * @dev: device structure representing parent device.
> + *
> + * Remove device from list of registered parent devices. Give a chance to free
> + * existing mediated devices for given device.
> + */
> +
> +void mdev_unregister_device(struct device *dev)
> +{
> + struct parent_device *parent;
> + bool force_remove = true;
> +
> + mutex_lock(&parent_list_lock);
> + parent = __find_parent_device(dev);
> +
> + if (!parent) {
> + mutex_unlock(&parent_list_lock);
> + return;
> + }
> + dev_info(dev, "MDEV: Unregistering\n");
> +
> + list_del(&parent->next);
> + class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
> +
> + device_for_each_child(dev, (void *)&force_remove,
> + mdev_device_remove_cb);
> +
> + parent_remove_sysfs_files(parent);
> +
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> +}
> +EXPORT_SYMBOL(mdev_unregister_device);
> +
> +static void mdev_device_release(struct device *dev)
> +{
> + struct mdev_device *mdev = to_mdev_device(dev);
> +
> + dev_dbg(&mdev->dev, "MDEV: destroying\n");
> + kfree(mdev);
> +}
> +
> +int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
> +{
> + int ret;
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type = to_mdev_type(kobj);
> +
> + parent = mdev_get_parent(type->parent);
> + if (!parent)
> + return -EINVAL;
> +
> + mutex_lock(&parent->lock);
> +
> + /* Check for duplicate */
> + if (mdev_device_exist(parent, uuid)) {
> + ret = -EEXIST;
> + goto create_err;
> + }
> +
> + mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> + if (!mdev) {
> + ret = -ENOMEM;
> + goto create_err;
> + }
> +
> + memcpy(&mdev->uuid, &uuid, sizeof(uuid_le));
> + mdev->parent = parent;
> + kref_init(&mdev->ref);
> +
> + mdev->dev.parent = dev;
> + mdev->dev.bus = &mdev_bus_type;
> + mdev->dev.release = mdev_device_release;
> + dev_set_name(&mdev->dev, "%pUl", uuid.b);
> +
> + ret = device_register(&mdev->dev);
> + if (ret) {
> + put_device(&mdev->dev);
> + goto create_err;
> + }
> +
> + ret = mdev_device_create_ops(kobj, mdev);
> + if (ret)
> + goto create_failed;
> +
> + ret = mdev_create_sysfs_files(&mdev->dev, type);
> + if (ret) {
> + mdev_device_remove_ops(mdev, true);
> + goto create_failed;
> + }
> +
> + mdev->type_kobj = kobj;
> + dev_dbg(&mdev->dev, "MDEV: created\n");
> +
> + mutex_unlock(&parent->lock);
> + return ret;
> +
> +create_failed:
> + device_unregister(&mdev->dev);
> +
> +create_err:
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +int mdev_device_remove(struct device *dev, bool force_remove)
> +{
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type;
> + int ret;
> +
> + mdev = to_mdev_device(dev);
> + type = to_mdev_type(mdev->type_kobj);
> + parent = mdev->parent;
> + mutex_lock(&parent->lock);
> +
> + ret = mdev_device_remove_ops(mdev, force_remove);
> + if (ret) {
> + mutex_unlock(&parent->lock);
> + return ret;
> + }
> +
> + mdev_remove_sysfs_files(dev, type);
> + device_unregister(dev);
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +static int __init mdev_init(void)
> +{
> + int ret;
> +
> + ret = mdev_bus_register();
> + if (ret) {
> + pr_err("Failed to register mdev bus\n");
> + return ret;
> + }
> +
> + mdev_bus_compat_class = class_compat_register("mdev_bus");
> + if (!mdev_bus_compat_class) {
> + mdev_bus_unregister();
> + return -ENOMEM;
> + }
> +
> + /*
> + * Attempt to load known vfio_mdev. This gives us a working environment
> + * without the user needing to explicitly load vfio_mdev driver.
> + */
> + request_module_nowait("vfio_mdev");
> +
> + return ret;
> +}
> +
> +static void __exit mdev_exit(void)
> +{
> + class_compat_unregister(mdev_bus_compat_class);
> + mdev_bus_unregister();
> +}
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-10-29 4:30 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-29 4:30 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
> +{
> + int ret;
> + struct parent_device *parent;
> +
> + /* check for mandatory ops */
> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
> + return -EINVAL;
> +
> + dev = get_device(dev);
> + if (!dev)
> + return -EINVAL;
> +
> + mutex_lock(&parent_list_lock);
> +
> + /* Check for duplicate */
> + parent = __find_parent_device(dev);
> + if (parent) {
> + ret = -EEXIST;
> + goto add_dev_err;
> + }
> +
> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
> + if (!parent) {
> + ret = -ENOMEM;
> + goto add_dev_err;
> + }
> +
> + kref_init(&parent->ref);
> + mutex_init(&parent->lock);
> +
> + parent->dev = dev;
> + parent->ops = ops;
> +
> + ret = parent_create_sysfs_files(parent);
> + if (ret) {
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> + return ret;
> + }
> +
> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
> + if (ret)
> + dev_warn(dev, "Failed to create compatibility class link\n");
> +
Hi Kirti,
Like I replied to previous version:
http://www.spinics.net/lists/kvm/msg139331.html
You can always check if mdev_bus_compat_class already registered
here, and register it if not yet. Same logic should be adopted to
mdev_init.
Current implementation will simply panic if configured as builtin,
which is rare but far from impossible.
--
Thanks,
Jike
> + list_add(&parent->next, &parent_list);
> + mutex_unlock(&parent_list_lock);
> +
> + dev_info(dev, "MDEV: Registered\n");
> + return 0;
> +
> +add_dev_err:
> + mutex_unlock(&parent_list_lock);
> + put_device(dev);
> + return ret;
> +}
> +EXPORT_SYMBOL(mdev_register_device);
> +
> +/*
> + * mdev_unregister_device : Unregister a parent device
> + * @dev: device structure representing parent device.
> + *
> + * Remove device from list of registered parent devices. Give a chance to free
> + * existing mediated devices for given device.
> + */
> +
> +void mdev_unregister_device(struct device *dev)
> +{
> + struct parent_device *parent;
> + bool force_remove = true;
> +
> + mutex_lock(&parent_list_lock);
> + parent = __find_parent_device(dev);
> +
> + if (!parent) {
> + mutex_unlock(&parent_list_lock);
> + return;
> + }
> + dev_info(dev, "MDEV: Unregistering\n");
> +
> + list_del(&parent->next);
> + class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
> +
> + device_for_each_child(dev, (void *)&force_remove,
> + mdev_device_remove_cb);
> +
> + parent_remove_sysfs_files(parent);
> +
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> +}
> +EXPORT_SYMBOL(mdev_unregister_device);
> +
> +static void mdev_device_release(struct device *dev)
> +{
> + struct mdev_device *mdev = to_mdev_device(dev);
> +
> + dev_dbg(&mdev->dev, "MDEV: destroying\n");
> + kfree(mdev);
> +}
> +
> +int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
> +{
> + int ret;
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type = to_mdev_type(kobj);
> +
> + parent = mdev_get_parent(type->parent);
> + if (!parent)
> + return -EINVAL;
> +
> + mutex_lock(&parent->lock);
> +
> + /* Check for duplicate */
> + if (mdev_device_exist(parent, uuid)) {
> + ret = -EEXIST;
> + goto create_err;
> + }
> +
> + mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> + if (!mdev) {
> + ret = -ENOMEM;
> + goto create_err;
> + }
> +
> + memcpy(&mdev->uuid, &uuid, sizeof(uuid_le));
> + mdev->parent = parent;
> + kref_init(&mdev->ref);
> +
> + mdev->dev.parent = dev;
> + mdev->dev.bus = &mdev_bus_type;
> + mdev->dev.release = mdev_device_release;
> + dev_set_name(&mdev->dev, "%pUl", uuid.b);
> +
> + ret = device_register(&mdev->dev);
> + if (ret) {
> + put_device(&mdev->dev);
> + goto create_err;
> + }
> +
> + ret = mdev_device_create_ops(kobj, mdev);
> + if (ret)
> + goto create_failed;
> +
> + ret = mdev_create_sysfs_files(&mdev->dev, type);
> + if (ret) {
> + mdev_device_remove_ops(mdev, true);
> + goto create_failed;
> + }
> +
> + mdev->type_kobj = kobj;
> + dev_dbg(&mdev->dev, "MDEV: created\n");
> +
> + mutex_unlock(&parent->lock);
> + return ret;
> +
> +create_failed:
> + device_unregister(&mdev->dev);
> +
> +create_err:
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +int mdev_device_remove(struct device *dev, bool force_remove)
> +{
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type;
> + int ret;
> +
> + mdev = to_mdev_device(dev);
> + type = to_mdev_type(mdev->type_kobj);
> + parent = mdev->parent;
> + mutex_lock(&parent->lock);
> +
> + ret = mdev_device_remove_ops(mdev, force_remove);
> + if (ret) {
> + mutex_unlock(&parent->lock);
> + return ret;
> + }
> +
> + mdev_remove_sysfs_files(dev, type);
> + device_unregister(dev);
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +static int __init mdev_init(void)
> +{
> + int ret;
> +
> + ret = mdev_bus_register();
> + if (ret) {
> + pr_err("Failed to register mdev bus\n");
> + return ret;
> + }
> +
> + mdev_bus_compat_class = class_compat_register("mdev_bus");
> + if (!mdev_bus_compat_class) {
> + mdev_bus_unregister();
> + return -ENOMEM;
> + }
> +
> + /*
> + * Attempt to load known vfio_mdev. This gives us a working environment
> + * without the user needing to explicitly load vfio_mdev driver.
> + */
> + request_module_nowait("vfio_mdev");
> +
> + return ret;
> +}
> +
> +static void __exit mdev_exit(void)
> +{
> + class_compat_unregister(mdev_bus_compat_class);
> + mdev_bus_unregister();
> +}
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 01/19] vfio: Mediated device Core driver
2016-10-29 4:30 ` [Qemu-devel] " Jike Song
@ 2016-10-29 10:06 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-29 10:06 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 1812 bytes --]
On 10/29/2016 10:00 AM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
>> +{
>> + int ret;
>> + struct parent_device *parent;
>> +
>> + /* check for mandatory ops */
>> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
>> + return -EINVAL;
>> +
>> + dev = get_device(dev);
>> + if (!dev)
>> + return -EINVAL;
>> +
>> + mutex_lock(&parent_list_lock);
>> +
>> + /* Check for duplicate */
>> + parent = __find_parent_device(dev);
>> + if (parent) {
>> + ret = -EEXIST;
>> + goto add_dev_err;
>> + }
>> +
>> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
>> + if (!parent) {
>> + ret = -ENOMEM;
>> + goto add_dev_err;
>> + }
>> +
>> + kref_init(&parent->ref);
>> + mutex_init(&parent->lock);
>> +
>> + parent->dev = dev;
>> + parent->ops = ops;
>> +
>> + ret = parent_create_sysfs_files(parent);
>> + if (ret) {
>> + mutex_unlock(&parent_list_lock);
>> + mdev_put_parent(parent);
>> + return ret;
>> + }
>> +
>> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
>> + if (ret)
>> + dev_warn(dev, "Failed to create compatibility class link\n");
>> +
>
> Hi Kirti,
>
> Like I replied to previous version:
>
> http://www.spinics.net/lists/kvm/msg139331.html
>
Hi Jike,
I saw your reply but by that time v10 version of patch series was out
for review.
> You can always check if mdev_bus_compat_class already registered
> here, and register it if not yet. Same logic should be adopted to
> mdev_init.
>
> Current implementation will simply panic if configured as builtin,
> which is rare but far from impossible.
>
Can you verify attached patch with v10 patch-set whether this works for you?
I'll incorporate this change in my next version.
Thanks,
Kirti
[-- Attachment #2: 0001-Register-mdev_bus-class-on-first-mdev_device_registe.patch --]
[-- Type: text/plain, Size: 2163 bytes --]
From: Kirti Wankhede <kwankhede@nvidia.com>
Date: Sat, 29 Oct 2016 15:12:01 +0530
Subject: [PATCH 1/1] Register mdev_bus class on first mdev_device_register
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
---
drivers/vfio/mdev/mdev_core.c | 30 +++++++++++++++++-------------
1 file changed, 17 insertions(+), 13 deletions(-)
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 9d8fa5c91c2e..54c59f325336 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -187,13 +187,18 @@ int mdev_register_device(struct device *dev, const struct parent_ops *ops)
parent->dev = dev;
parent->ops = ops;
- ret = parent_create_sysfs_files(parent);
- if (ret) {
- mutex_unlock(&parent_list_lock);
- mdev_put_parent(parent);
- return ret;
+ if (!mdev_bus_compat_class) {
+ mdev_bus_compat_class = class_compat_register("mdev_bus");
+ if (!mdev_bus_compat_class) {
+ ret = -ENOMEM;
+ goto add_dev_err;
+ }
}
+ ret = parent_create_sysfs_files(parent);
+ if (ret)
+ goto add_dev_err;
+
ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
if (ret)
dev_warn(dev, "Failed to create compatibility class link\n");
@@ -206,7 +211,10 @@ int mdev_register_device(struct device *dev, const struct parent_ops *ops)
add_dev_err:
mutex_unlock(&parent_list_lock);
- put_device(dev);
+ if (parent)
+ mdev_put_parent(parent);
+ else
+ put_device(dev);
return ret;
}
EXPORT_SYMBOL(mdev_register_device);
@@ -354,12 +362,6 @@ static int __init mdev_init(void)
return ret;
}
- mdev_bus_compat_class = class_compat_register("mdev_bus");
- if (!mdev_bus_compat_class) {
- mdev_bus_unregister();
- return -ENOMEM;
- }
-
/*
* Attempt to load known vfio_mdev. This gives us a working environment
* without the user needing to explicitly load vfio_mdev driver.
@@ -371,7 +373,9 @@ static int __init mdev_init(void)
static void __exit mdev_exit(void)
{
- class_compat_unregister(mdev_bus_compat_class);
+ if (mdev_bus_compat_class)
+ class_compat_unregister(mdev_bus_compat_class);
+
mdev_bus_unregister();
}
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-10-29 10:06 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-29 10:06 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 1812 bytes --]
On 10/29/2016 10:00 AM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
>> +{
>> + int ret;
>> + struct parent_device *parent;
>> +
>> + /* check for mandatory ops */
>> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
>> + return -EINVAL;
>> +
>> + dev = get_device(dev);
>> + if (!dev)
>> + return -EINVAL;
>> +
>> + mutex_lock(&parent_list_lock);
>> +
>> + /* Check for duplicate */
>> + parent = __find_parent_device(dev);
>> + if (parent) {
>> + ret = -EEXIST;
>> + goto add_dev_err;
>> + }
>> +
>> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
>> + if (!parent) {
>> + ret = -ENOMEM;
>> + goto add_dev_err;
>> + }
>> +
>> + kref_init(&parent->ref);
>> + mutex_init(&parent->lock);
>> +
>> + parent->dev = dev;
>> + parent->ops = ops;
>> +
>> + ret = parent_create_sysfs_files(parent);
>> + if (ret) {
>> + mutex_unlock(&parent_list_lock);
>> + mdev_put_parent(parent);
>> + return ret;
>> + }
>> +
>> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
>> + if (ret)
>> + dev_warn(dev, "Failed to create compatibility class link\n");
>> +
>
> Hi Kirti,
>
> Like I replied to previous version:
>
> http://www.spinics.net/lists/kvm/msg139331.html
>
Hi Jike,
I saw your reply but by that time v10 version of patch series was out
for review.
> You can always check if mdev_bus_compat_class already registered
> here, and register it if not yet. Same logic should be adopted to
> mdev_init.
>
> Current implementation will simply panic if configured as builtin,
> which is rare but far from impossible.
>
Can you verify attached patch with v10 patch-set whether this works for you?
I'll incorporate this change in my next version.
Thanks,
Kirti
[-- Attachment #2: 0001-Register-mdev_bus-class-on-first-mdev_device_registe.patch --]
[-- Type: text/plain, Size: 2163 bytes --]
From: Kirti Wankhede <kwankhede@nvidia.com>
Date: Sat, 29 Oct 2016 15:12:01 +0530
Subject: [PATCH 1/1] Register mdev_bus class on first mdev_device_register
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
---
drivers/vfio/mdev/mdev_core.c | 30 +++++++++++++++++-------------
1 file changed, 17 insertions(+), 13 deletions(-)
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 9d8fa5c91c2e..54c59f325336 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -187,13 +187,18 @@ int mdev_register_device(struct device *dev, const struct parent_ops *ops)
parent->dev = dev;
parent->ops = ops;
- ret = parent_create_sysfs_files(parent);
- if (ret) {
- mutex_unlock(&parent_list_lock);
- mdev_put_parent(parent);
- return ret;
+ if (!mdev_bus_compat_class) {
+ mdev_bus_compat_class = class_compat_register("mdev_bus");
+ if (!mdev_bus_compat_class) {
+ ret = -ENOMEM;
+ goto add_dev_err;
+ }
}
+ ret = parent_create_sysfs_files(parent);
+ if (ret)
+ goto add_dev_err;
+
ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
if (ret)
dev_warn(dev, "Failed to create compatibility class link\n");
@@ -206,7 +211,10 @@ int mdev_register_device(struct device *dev, const struct parent_ops *ops)
add_dev_err:
mutex_unlock(&parent_list_lock);
- put_device(dev);
+ if (parent)
+ mdev_put_parent(parent);
+ else
+ put_device(dev);
return ret;
}
EXPORT_SYMBOL(mdev_register_device);
@@ -354,12 +362,6 @@ static int __init mdev_init(void)
return ret;
}
- mdev_bus_compat_class = class_compat_register("mdev_bus");
- if (!mdev_bus_compat_class) {
- mdev_bus_unregister();
- return -ENOMEM;
- }
-
/*
* Attempt to load known vfio_mdev. This gives us a working environment
* without the user needing to explicitly load vfio_mdev driver.
@@ -371,7 +373,9 @@ static int __init mdev_init(void)
static void __exit mdev_exit(void)
{
- class_compat_unregister(mdev_bus_compat_class);
+ if (mdev_bus_compat_class)
+ class_compat_unregister(mdev_bus_compat_class);
+
mdev_bus_unregister();
}
--
2.7.0
^ permalink raw reply related [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-28 20:33 ` [Qemu-devel] " Alex Williamson
@ 2016-10-29 10:37 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-29 10:37 UTC (permalink / raw)
To: Alex Williamson
Cc: Jike Song, pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian,
bjsdjshi, linux-kernel
On 10/29/2016 2:03 AM, Alex Williamson wrote:
> On Sat, 29 Oct 2016 01:32:35 +0530
> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>
>> On 10/28/2016 6:10 PM, Alex Williamson wrote:
>>> On Fri, 28 Oct 2016 15:33:58 +0800
>>> Jike Song <jike.song@intel.com> wrote:
>>>
...
>>>>>
>>>>> +/*
>>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
>>>>> + * vfio_pfn. In that case, exit from loop.
>>>>> + */
>>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
>>>>> +{
>>>>> + struct vfio_domain *domain = iommu->external_domain;
>>>>> + struct rb_node *n;
>>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>>>>> +
>>>>> + do {
>>>>> + prev_vpfn = vpfn;
>>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>>>>> +
>>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
>>>>> +
>>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
>>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>>>>> +
>>>>> + if ((vpfn->iova >= unmap->iova) &&
>>>>> + (vpfn->iova < unmap->iova + unmap->size))
>>>>> + break;
>>>>> + }
>>>>> +
>>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>>>>> +
>>>>> + /* Notify any listeners about DMA_UNMAP */
>>>>> + if (vpfn)
>>>>> + blocking_notifier_call_chain(&iommu->notifier,
>>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>>>> + &vpfn->pfn);
>>>>
>>>> Hi Kirti,
>>>>
>>>> The information carried by notifier is only a pfn.
>>>>
>>>> Since your pin/unpin interfaces design, it's the vendor driver who should
>>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
>>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
>>>> for multiple times.
>>>>
>>>> With the notifier carrying only a pfn, to find the iova by this pfn,
>>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
>>>> too much.
>>>>
>>>> Since the vendor could also suffer from IOMMU-compatible problem,
>>>> which means a local cache is always helpful, so I'd like to have the
>>>> iova carried to the notifier.
>>>>
>>>> What'd you say?
>>>
>>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
>>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
>>> notifier through to the vendor driver must be based on the same.
>>
>> Host pfn should be unique, right?
>
> Let's say a user does a malloc of a single page and does 100 calls to
> MAP_DMA populating 100 pages of IOVA space all backed by the same
> malloc'd page. This is valid, I have unit tests that do essentially
> this. Those will all have the same pfn. The user then does an
> UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> everything matching that pfn? Of course not, they only unmapped that
> one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> driver MUST therefore also work based on IOVA. This is not an academic
> problem, address space aliases exist in real VMs, imagine a virtual
> IOMMU. Thanks,
>
So struct vfio_iommu_type1_dma_unmap should be passed as argument to
notifier callback:
if (unmapped && iommu->external_domain)
- vfio_notifier_call_chain(iommu, unmap);
+ blocking_notifier_call_chain(&iommu->notifier,
+ VFIO_IOMMU_NOTIFY_DMA_UNMAP,
+ unmap);
Then vendor driver should find pfns he has pinned from this range of
iovas, then invalidate and unpin pfns. Right?
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-29 10:37 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-29 10:37 UTC (permalink / raw)
To: Alex Williamson
Cc: Jike Song, pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian,
bjsdjshi, linux-kernel
On 10/29/2016 2:03 AM, Alex Williamson wrote:
> On Sat, 29 Oct 2016 01:32:35 +0530
> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>
>> On 10/28/2016 6:10 PM, Alex Williamson wrote:
>>> On Fri, 28 Oct 2016 15:33:58 +0800
>>> Jike Song <jike.song@intel.com> wrote:
>>>
...
>>>>>
>>>>> +/*
>>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
>>>>> + * vfio_pfn. In that case, exit from loop.
>>>>> + */
>>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
>>>>> +{
>>>>> + struct vfio_domain *domain = iommu->external_domain;
>>>>> + struct rb_node *n;
>>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>>>>> +
>>>>> + do {
>>>>> + prev_vpfn = vpfn;
>>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>>>>> +
>>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
>>>>> +
>>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
>>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>>>>> +
>>>>> + if ((vpfn->iova >= unmap->iova) &&
>>>>> + (vpfn->iova < unmap->iova + unmap->size))
>>>>> + break;
>>>>> + }
>>>>> +
>>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>>>>> +
>>>>> + /* Notify any listeners about DMA_UNMAP */
>>>>> + if (vpfn)
>>>>> + blocking_notifier_call_chain(&iommu->notifier,
>>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>>>> + &vpfn->pfn);
>>>>
>>>> Hi Kirti,
>>>>
>>>> The information carried by notifier is only a pfn.
>>>>
>>>> Since your pin/unpin interfaces design, it's the vendor driver who should
>>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
>>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
>>>> for multiple times.
>>>>
>>>> With the notifier carrying only a pfn, to find the iova by this pfn,
>>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
>>>> too much.
>>>>
>>>> Since the vendor could also suffer from IOMMU-compatible problem,
>>>> which means a local cache is always helpful, so I'd like to have the
>>>> iova carried to the notifier.
>>>>
>>>> What'd you say?
>>>
>>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
>>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
>>> notifier through to the vendor driver must be based on the same.
>>
>> Host pfn should be unique, right?
>
> Let's say a user does a malloc of a single page and does 100 calls to
> MAP_DMA populating 100 pages of IOVA space all backed by the same
> malloc'd page. This is valid, I have unit tests that do essentially
> this. Those will all have the same pfn. The user then does an
> UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> everything matching that pfn? Of course not, they only unmapped that
> one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> driver MUST therefore also work based on IOVA. This is not an academic
> problem, address space aliases exist in real VMs, imagine a virtual
> IOMMU. Thanks,
>
So struct vfio_iommu_type1_dma_unmap should be passed as argument to
notifier callback:
if (unmapped && iommu->external_domain)
- vfio_notifier_call_chain(iommu, unmap);
+ blocking_notifier_call_chain(&iommu->notifier,
+ VFIO_IOMMU_NOTIFY_DMA_UNMAP,
+ unmap);
Then vendor driver should find pfns he has pinned from this range of
iovas, then invalidate and unpin pfns. Right?
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-29 10:37 ` [Qemu-devel] " Kirti Wankhede
(?)
@ 2016-10-29 14:03 ` Alex Williamson
-1 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-29 14:03 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Jike Song, pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian,
bjsdjshi, linux-kernel
On Sat, 29 Oct 2016 16:07:05 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> On 10/29/2016 2:03 AM, Alex Williamson wrote:
> > On Sat, 29 Oct 2016 01:32:35 +0530
> > Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >
> >> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> >>> On Fri, 28 Oct 2016 15:33:58 +0800
> >>> Jike Song <jike.song@intel.com> wrote:
> >>>
> ...
> >>>>>
> >>>>> +/*
> >>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> >>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> >>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> >>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> >>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> >>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> >>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> >>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
> >>>>> + * vfio_pfn. In that case, exit from loop.
> >>>>> + */
> >>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> >>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
> >>>>> +{
> >>>>> + struct vfio_domain *domain = iommu->external_domain;
> >>>>> + struct rb_node *n;
> >>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> >>>>> +
> >>>>> + do {
> >>>>> + prev_vpfn = vpfn;
> >>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> >>>>> +
> >>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
> >>>>> +
> >>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
> >>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> >>>>> +
> >>>>> + if ((vpfn->iova >= unmap->iova) &&
> >>>>> + (vpfn->iova < unmap->iova + unmap->size))
> >>>>> + break;
> >>>>> + }
> >>>>> +
> >>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> >>>>> +
> >>>>> + /* Notify any listeners about DMA_UNMAP */
> >>>>> + if (vpfn)
> >>>>> + blocking_notifier_call_chain(&iommu->notifier,
> >>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>>>> + &vpfn->pfn);
> >>>>
> >>>> Hi Kirti,
> >>>>
> >>>> The information carried by notifier is only a pfn.
> >>>>
> >>>> Since your pin/unpin interfaces design, it's the vendor driver who should
> >>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
> >>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> >>>> for multiple times.
> >>>>
> >>>> With the notifier carrying only a pfn, to find the iova by this pfn,
> >>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
> >>>> too much.
> >>>>
> >>>> Since the vendor could also suffer from IOMMU-compatible problem,
> >>>> which means a local cache is always helpful, so I'd like to have the
> >>>> iova carried to the notifier.
> >>>>
> >>>> What'd you say?
> >>>
> >>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> >>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> >>> notifier through to the vendor driver must be based on the same.
> >>
> >> Host pfn should be unique, right?
> >
> > Let's say a user does a malloc of a single page and does 100 calls to
> > MAP_DMA populating 100 pages of IOVA space all backed by the same
> > malloc'd page. This is valid, I have unit tests that do essentially
> > this. Those will all have the same pfn. The user then does an
> > UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> > everything matching that pfn? Of course not, they only unmapped that
> > one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> > UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> > driver MUST therefore also work based on IOVA. This is not an academic
> > problem, address space aliases exist in real VMs, imagine a virtual
> > IOMMU. Thanks,
> >
>
>
> So struct vfio_iommu_type1_dma_unmap should be passed as argument to
> notifier callback:
>
> if (unmapped && iommu->external_domain)
> - vfio_notifier_call_chain(iommu, unmap);
> + blocking_notifier_call_chain(&iommu->notifier,
> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> + unmap);
>
> Then vendor driver should find pfns he has pinned from this range of
> iovas, then invalidate and unpin pfns. Right?
That seems like a valid choice. It's probably better than calling the
notifier for each page of iova. Thanks,
Alex
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-29 14:03 ` Alex Williamson
0 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-29 14:03 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Jike Song, cjia, kvm, qemu-devel, linux-kernel, kevin.tian,
kraxel, pbonzini, bjsdjshi
On Sat, 29 Oct 2016 16:07:05 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> On 10/29/2016 2:03 AM, Alex Williamson wrote:
> > On Sat, 29 Oct 2016 01:32:35 +0530
> > Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >
> >> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> >>> On Fri, 28 Oct 2016 15:33:58 +0800
> >>> Jike Song <jike.song@intel.com> wrote:
> >>>
> ...
> >>>>>
> >>>>> +/*
> >>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> >>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> >>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> >>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> >>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> >>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> >>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> >>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
> >>>>> + * vfio_pfn. In that case, exit from loop.
> >>>>> + */
> >>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> >>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
> >>>>> +{
> >>>>> + struct vfio_domain *domain = iommu->external_domain;
> >>>>> + struct rb_node *n;
> >>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> >>>>> +
> >>>>> + do {
> >>>>> + prev_vpfn = vpfn;
> >>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> >>>>> +
> >>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
> >>>>> +
> >>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
> >>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> >>>>> +
> >>>>> + if ((vpfn->iova >= unmap->iova) &&
> >>>>> + (vpfn->iova < unmap->iova + unmap->size))
> >>>>> + break;
> >>>>> + }
> >>>>> +
> >>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> >>>>> +
> >>>>> + /* Notify any listeners about DMA_UNMAP */
> >>>>> + if (vpfn)
> >>>>> + blocking_notifier_call_chain(&iommu->notifier,
> >>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>>>> + &vpfn->pfn);
> >>>>
> >>>> Hi Kirti,
> >>>>
> >>>> The information carried by notifier is only a pfn.
> >>>>
> >>>> Since your pin/unpin interfaces design, it's the vendor driver who should
> >>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
> >>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> >>>> for multiple times.
> >>>>
> >>>> With the notifier carrying only a pfn, to find the iova by this pfn,
> >>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
> >>>> too much.
> >>>>
> >>>> Since the vendor could also suffer from IOMMU-compatible problem,
> >>>> which means a local cache is always helpful, so I'd like to have the
> >>>> iova carried to the notifier.
> >>>>
> >>>> What'd you say?
> >>>
> >>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> >>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> >>> notifier through to the vendor driver must be based on the same.
> >>
> >> Host pfn should be unique, right?
> >
> > Let's say a user does a malloc of a single page and does 100 calls to
> > MAP_DMA populating 100 pages of IOVA space all backed by the same
> > malloc'd page. This is valid, I have unit tests that do essentially
> > this. Those will all have the same pfn. The user then does an
> > UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> > everything matching that pfn? Of course not, they only unmapped that
> > one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> > UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> > driver MUST therefore also work based on IOVA. This is not an academic
> > problem, address space aliases exist in real VMs, imagine a virtual
> > IOMMU. Thanks,
> >
>
>
> So struct vfio_iommu_type1_dma_unmap should be passed as argument to
> notifier callback:
>
> if (unmapped && iommu->external_domain)
> - vfio_notifier_call_chain(iommu, unmap);
> + blocking_notifier_call_chain(&iommu->notifier,
> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> + unmap);
>
> Then vendor driver should find pfns he has pinned from this range of
> iovas, then invalidate and unpin pfns. Right?
That seems like a valid choice. It's probably better than calling the
notifier for each page of iova. Thanks,
Alex
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-29 14:03 ` Alex Williamson
0 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-10-29 14:03 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Jike Song, pbonzini, kraxel, cjia, qemu-devel, kvm, kevin.tian,
bjsdjshi, linux-kernel
On Sat, 29 Oct 2016 16:07:05 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:
> On 10/29/2016 2:03 AM, Alex Williamson wrote:
> > On Sat, 29 Oct 2016 01:32:35 +0530
> > Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >
> >> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> >>> On Fri, 28 Oct 2016 15:33:58 +0800
> >>> Jike Song <jike.song@intel.com> wrote:
> >>>
> ...
> >>>>>
> >>>>> +/*
> >>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> >>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> >>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> >>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> >>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> >>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> >>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> >>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
> >>>>> + * vfio_pfn. In that case, exit from loop.
> >>>>> + */
> >>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> >>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
> >>>>> +{
> >>>>> + struct vfio_domain *domain = iommu->external_domain;
> >>>>> + struct rb_node *n;
> >>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> >>>>> +
> >>>>> + do {
> >>>>> + prev_vpfn = vpfn;
> >>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> >>>>> +
> >>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
> >>>>> +
> >>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
> >>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> >>>>> +
> >>>>> + if ((vpfn->iova >= unmap->iova) &&
> >>>>> + (vpfn->iova < unmap->iova + unmap->size))
> >>>>> + break;
> >>>>> + }
> >>>>> +
> >>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> >>>>> +
> >>>>> + /* Notify any listeners about DMA_UNMAP */
> >>>>> + if (vpfn)
> >>>>> + blocking_notifier_call_chain(&iommu->notifier,
> >>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>>>> + &vpfn->pfn);
> >>>>
> >>>> Hi Kirti,
> >>>>
> >>>> The information carried by notifier is only a pfn.
> >>>>
> >>>> Since your pin/unpin interfaces design, it's the vendor driver who should
> >>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
> >>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> >>>> for multiple times.
> >>>>
> >>>> With the notifier carrying only a pfn, to find the iova by this pfn,
> >>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
> >>>> too much.
> >>>>
> >>>> Since the vendor could also suffer from IOMMU-compatible problem,
> >>>> which means a local cache is always helpful, so I'd like to have the
> >>>> iova carried to the notifier.
> >>>>
> >>>> What'd you say?
> >>>
> >>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> >>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> >>> notifier through to the vendor driver must be based on the same.
> >>
> >> Host pfn should be unique, right?
> >
> > Let's say a user does a malloc of a single page and does 100 calls to
> > MAP_DMA populating 100 pages of IOVA space all backed by the same
> > malloc'd page. This is valid, I have unit tests that do essentially
> > this. Those will all have the same pfn. The user then does an
> > UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> > everything matching that pfn? Of course not, they only unmapped that
> > one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> > UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> > driver MUST therefore also work based on IOVA. This is not an academic
> > problem, address space aliases exist in real VMs, imagine a virtual
> > IOMMU. Thanks,
> >
>
>
> So struct vfio_iommu_type1_dma_unmap should be passed as argument to
> notifier callback:
>
> if (unmapped && iommu->external_domain)
> - vfio_notifier_call_chain(iommu, unmap);
> + blocking_notifier_call_chain(&iommu->notifier,
> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> + unmap);
>
> Then vendor driver should find pfns he has pinned from this range of
> iovas, then invalidate and unpin pfns. Right?
That seems like a valid choice. It's probably better than calling the
notifier for each page of iova. Thanks,
Alex
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 01/19] vfio: Mediated device Core driver
2016-10-29 10:06 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-29 18:11 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-29 18:11 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/29/2016 06:06 PM, Kirti Wankhede wrote:
>
>
> On 10/29/2016 10:00 AM, Jike Song wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
>>> +{
>>> + int ret;
>>> + struct parent_device *parent;
>>> +
>>> + /* check for mandatory ops */
>>> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
>>> + return -EINVAL;
>>> +
>>> + dev = get_device(dev);
>>> + if (!dev)
>>> + return -EINVAL;
>>> +
>>> + mutex_lock(&parent_list_lock);
>>> +
>>> + /* Check for duplicate */
>>> + parent = __find_parent_device(dev);
>>> + if (parent) {
>>> + ret = -EEXIST;
>>> + goto add_dev_err;
>>> + }
>>> +
>>> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
>>> + if (!parent) {
>>> + ret = -ENOMEM;
>>> + goto add_dev_err;
>>> + }
>>> +
>>> + kref_init(&parent->ref);
>>> + mutex_init(&parent->lock);
>>> +
>>> + parent->dev = dev;
>>> + parent->ops = ops;
>>> +
>>> + ret = parent_create_sysfs_files(parent);
>>> + if (ret) {
>>> + mutex_unlock(&parent_list_lock);
>>> + mdev_put_parent(parent);
>>> + return ret;
>>> + }
>>> +
>>> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
>>> + if (ret)
>>> + dev_warn(dev, "Failed to create compatibility class link\n");
>>> +
>>
>> Hi Kirti,
>>
>> Like I replied to previous version:
>>
>> http://www.spinics.net/lists/kvm/msg139331.html
>>
>
> Hi Jike,
>
> I saw your reply but by that time v10 version of patch series was out
> for review.
>
Ah..yes, I forgot that :)
>> You can always check if mdev_bus_compat_class already registered
>> here, and register it if not yet. Same logic should be adopted to
>> mdev_init.
>>
>> Current implementation will simply panic if configured as builtin,
>> which is rare but far from impossible.
>>
>
> Can you verify attached patch with v10 patch-set whether this works for you?
> I'll incorporate this change in my next version.
>
Seems cool. But would you please also keep the register in mdev_init(),
just check the 'in case it was already registered' case? Thanks!
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-10-29 18:11 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-29 18:11 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/29/2016 06:06 PM, Kirti Wankhede wrote:
>
>
> On 10/29/2016 10:00 AM, Jike Song wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
>>> +{
>>> + int ret;
>>> + struct parent_device *parent;
>>> +
>>> + /* check for mandatory ops */
>>> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
>>> + return -EINVAL;
>>> +
>>> + dev = get_device(dev);
>>> + if (!dev)
>>> + return -EINVAL;
>>> +
>>> + mutex_lock(&parent_list_lock);
>>> +
>>> + /* Check for duplicate */
>>> + parent = __find_parent_device(dev);
>>> + if (parent) {
>>> + ret = -EEXIST;
>>> + goto add_dev_err;
>>> + }
>>> +
>>> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
>>> + if (!parent) {
>>> + ret = -ENOMEM;
>>> + goto add_dev_err;
>>> + }
>>> +
>>> + kref_init(&parent->ref);
>>> + mutex_init(&parent->lock);
>>> +
>>> + parent->dev = dev;
>>> + parent->ops = ops;
>>> +
>>> + ret = parent_create_sysfs_files(parent);
>>> + if (ret) {
>>> + mutex_unlock(&parent_list_lock);
>>> + mdev_put_parent(parent);
>>> + return ret;
>>> + }
>>> +
>>> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
>>> + if (ret)
>>> + dev_warn(dev, "Failed to create compatibility class link\n");
>>> +
>>
>> Hi Kirti,
>>
>> Like I replied to previous version:
>>
>> http://www.spinics.net/lists/kvm/msg139331.html
>>
>
> Hi Jike,
>
> I saw your reply but by that time v10 version of patch series was out
> for review.
>
Ah..yes, I forgot that :)
>> You can always check if mdev_bus_compat_class already registered
>> here, and register it if not yet. Same logic should be adopted to
>> mdev_init.
>>
>> Current implementation will simply panic if configured as builtin,
>> which is rare but far from impossible.
>>
>
> Can you verify attached patch with v10 patch-set whether this works for you?
> I'll incorporate this change in my next version.
>
Seems cool. But would you please also keep the register in mdev_init(),
just check the 'in case it was already registered' case? Thanks!
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-31 3:50 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-31 3:50 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> about DMA_UNMAP.
> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> Vendor driver should register notifer using these APIs.
> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> mappings.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> ---
> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> include/linux/vfio.h | 11 +++++
> 3 files changed, 163 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 28b50ca14c52..ff05ac6b1e90 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1891,6 +1891,79 @@ err_unpin_pages:
> }
> EXPORT_SYMBOL(vfio_unpin_pages);
>
> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> +{
Hi Kirti,
Given that below 4 methods are members of vfio_iommu_driver_ops:
pin_pages
unpin_pages
register_notifier
unregister_notifier
the names of exposed VFIO APIs could possibly be clearer:
vfio_iommu_pin_pages
vfio_iommu_unpin_pages
vfio_iommu_register_notifier
vfio_iommu_unreigster_nodier
--
Thanks,
Jike
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_register_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->register_notifier))
> + ret = driver->ops->register_notifier(container->iommu_data, nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_register_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_register_notifier);
> +
> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_unregister_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->unregister_notifier))
> + ret = driver->ops->unregister_notifier(container->iommu_data,
> + nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_unregister_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_unregister_notifier);
> +
> /**
> * Module/class support
> */
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 5add11a147e1..a4bd331ac0fd 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -37,6 +37,7 @@
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> #include <linux/mdev.h>
> +#include <linux/notifier.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -59,6 +60,7 @@ struct vfio_iommu {
> struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> + struct blocking_notifier_head notifier;
> bool v2;
> bool nesting;
> };
> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> - if (!iommu->external_domain) {
> + /* Fail if notifier list is empty */
> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> ret = -EINVAL;
> goto pin_done;
> }
> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> return bitmap;
> }
>
> +/*
> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> + * receiving notifier callback, vendor driver should invalidate the mapping and
> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> + * searching for next vfio_pfn in rb tree, start search from first node again.
> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> + * from rb tree and so in next search vfio_pfn would be same as previous
> + * vfio_pfn. In that case, exit from loop.
> + */
> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> + struct vfio_iommu_type1_dma_unmap *unmap)
> +{
> + struct vfio_domain *domain = iommu->external_domain;
> + struct rb_node *n;
> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> +
> + do {
> + prev_vpfn = vpfn;
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + n = rb_first(&domain->external_addr_space->pfn_list);
> +
> + for (; n; n = rb_next(n), vpfn = NULL) {
> + vpfn = rb_entry(n, struct vfio_pfn, node);
> +
> + if ((vpfn->iova >= unmap->iova) &&
> + (vpfn->iova < unmap->iova + unmap->size))
> + break;
> + }
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +
> + /* Notify any listeners about DMA_UNMAP */
> + if (vpfn)
> + blocking_notifier_call_chain(&iommu->notifier,
> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> + &vpfn->pfn);
> + } while (vpfn && (prev_vpfn != vpfn));
> +
> + WARN_ON(vpfn);
> +}
> +
> static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
> struct vfio_iommu_type1_dma_unmap *unmap)
> {
> @@ -844,6 +891,9 @@ unlock:
> /* Report how much was unmapped */
> unmap->size = unmapped;
>
> + if (unmapped && iommu->external_domain)
> + vfio_notifier_call_chain(iommu, unmap);
> +
> return ret;
> }
>
> @@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> INIT_LIST_HEAD(&iommu->domain_list);
> iommu->dma_list = RB_ROOT;
> mutex_init(&iommu->lock);
> + BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
>
> return iommu;
> }
> @@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
> return -ENOTTY;
> }
>
> +static int vfio_iommu_type1_register_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_register(&iommu->notifier, nb);
> +}
> +
> +static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_unregister(&iommu->notifier, nb);
> +}
> +
> static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> - .name = "vfio-iommu-type1",
> - .owner = THIS_MODULE,
> - .open = vfio_iommu_type1_open,
> - .release = vfio_iommu_type1_release,
> - .ioctl = vfio_iommu_type1_ioctl,
> - .attach_group = vfio_iommu_type1_attach_group,
> - .detach_group = vfio_iommu_type1_detach_group,
> - .pin_pages = vfio_iommu_type1_pin_pages,
> - .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .name = "vfio-iommu-type1",
> + .owner = THIS_MODULE,
> + .open = vfio_iommu_type1_open,
> + .release = vfio_iommu_type1_release,
> + .ioctl = vfio_iommu_type1_ioctl,
> + .attach_group = vfio_iommu_type1_attach_group,
> + .detach_group = vfio_iommu_type1_detach_group,
> + .pin_pages = vfio_iommu_type1_pin_pages,
> + .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .register_notifier = vfio_iommu_type1_register_notifier,
> + .unregister_notifier = vfio_iommu_type1_unregister_notifier,
> };
>
> static int __init vfio_iommu_type1_init(void)
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 0609a2052846..4c91ce8bfaeb 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
> unsigned long *phys_pfn);
> long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> long npage);
> + int (*register_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> + int (*unregister_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> };
>
> extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> @@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> long npage);
>
> +#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
> +
> +extern int vfio_register_notifier(struct device *dev,
> + struct notifier_block *nb);
> +
> +extern int vfio_unregister_notifier(struct device *dev,
> + struct notifier_block *nb);
> /*
> * IRQfd - generic
> */
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-31 3:50 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-31 3:50 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
> about DMA_UNMAP.
> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
> Vendor driver should register notifer using these APIs.
> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
> mappings.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
> ---
> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
> include/linux/vfio.h | 11 +++++
> 3 files changed, 163 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 28b50ca14c52..ff05ac6b1e90 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1891,6 +1891,79 @@ err_unpin_pages:
> }
> EXPORT_SYMBOL(vfio_unpin_pages);
>
> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
> +{
Hi Kirti,
Given that below 4 methods are members of vfio_iommu_driver_ops:
pin_pages
unpin_pages
register_notifier
unregister_notifier
the names of exposed VFIO APIs could possibly be clearer:
vfio_iommu_pin_pages
vfio_iommu_unpin_pages
vfio_iommu_register_notifier
vfio_iommu_unreigster_nodier
--
Thanks,
Jike
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_register_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->register_notifier))
> + ret = driver->ops->register_notifier(container->iommu_data, nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_register_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_register_notifier);
> +
> +int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !nb)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_unregister_nb;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->unregister_notifier))
> + ret = driver->ops->unregister_notifier(container->iommu_data,
> + nb);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_unregister_nb:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_unregister_notifier);
> +
> /**
> * Module/class support
> */
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 5add11a147e1..a4bd331ac0fd 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -37,6 +37,7 @@
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> #include <linux/mdev.h>
> +#include <linux/notifier.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -59,6 +60,7 @@ struct vfio_iommu {
> struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> + struct blocking_notifier_head notifier;
> bool v2;
> bool nesting;
> };
> @@ -549,7 +551,8 @@ static long vfio_iommu_type1_pin_pages(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> - if (!iommu->external_domain) {
> + /* Fail if notifier list is empty */
> + if ((!iommu->external_domain) || (!iommu->notifier.head)) {
> ret = -EINVAL;
> goto pin_done;
> }
> @@ -768,6 +771,50 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
> return bitmap;
> }
>
> +/*
> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> + * receiving notifier callback, vendor driver should invalidate the mapping and
> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> + * searching for next vfio_pfn in rb tree, start search from first node again.
> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> + * from rb tree and so in next search vfio_pfn would be same as previous
> + * vfio_pfn. In that case, exit from loop.
> + */
> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> + struct vfio_iommu_type1_dma_unmap *unmap)
> +{
> + struct vfio_domain *domain = iommu->external_domain;
> + struct rb_node *n;
> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> +
> + do {
> + prev_vpfn = vpfn;
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + n = rb_first(&domain->external_addr_space->pfn_list);
> +
> + for (; n; n = rb_next(n), vpfn = NULL) {
> + vpfn = rb_entry(n, struct vfio_pfn, node);
> +
> + if ((vpfn->iova >= unmap->iova) &&
> + (vpfn->iova < unmap->iova + unmap->size))
> + break;
> + }
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> +
> + /* Notify any listeners about DMA_UNMAP */
> + if (vpfn)
> + blocking_notifier_call_chain(&iommu->notifier,
> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> + &vpfn->pfn);
> + } while (vpfn && (prev_vpfn != vpfn));
> +
> + WARN_ON(vpfn);
> +}
> +
> static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
> struct vfio_iommu_type1_dma_unmap *unmap)
> {
> @@ -844,6 +891,9 @@ unlock:
> /* Report how much was unmapped */
> unmap->size = unmapped;
>
> + if (unmapped && iommu->external_domain)
> + vfio_notifier_call_chain(iommu, unmap);
> +
> return ret;
> }
>
> @@ -1418,6 +1468,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
> INIT_LIST_HEAD(&iommu->domain_list);
> iommu->dma_list = RB_ROOT;
> mutex_init(&iommu->lock);
> + BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
>
> return iommu;
> }
> @@ -1555,16 +1606,34 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
> return -ENOTTY;
> }
>
> +static int vfio_iommu_type1_register_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_register(&iommu->notifier, nb);
> +}
> +
> +static int vfio_iommu_type1_unregister_notifier(void *iommu_data,
> + struct notifier_block *nb)
> +{
> + struct vfio_iommu *iommu = iommu_data;
> +
> + return blocking_notifier_chain_unregister(&iommu->notifier, nb);
> +}
> +
> static const struct vfio_iommu_driver_ops vfio_iommu_driver_ops_type1 = {
> - .name = "vfio-iommu-type1",
> - .owner = THIS_MODULE,
> - .open = vfio_iommu_type1_open,
> - .release = vfio_iommu_type1_release,
> - .ioctl = vfio_iommu_type1_ioctl,
> - .attach_group = vfio_iommu_type1_attach_group,
> - .detach_group = vfio_iommu_type1_detach_group,
> - .pin_pages = vfio_iommu_type1_pin_pages,
> - .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .name = "vfio-iommu-type1",
> + .owner = THIS_MODULE,
> + .open = vfio_iommu_type1_open,
> + .release = vfio_iommu_type1_release,
> + .ioctl = vfio_iommu_type1_ioctl,
> + .attach_group = vfio_iommu_type1_attach_group,
> + .detach_group = vfio_iommu_type1_detach_group,
> + .pin_pages = vfio_iommu_type1_pin_pages,
> + .unpin_pages = vfio_iommu_type1_unpin_pages,
> + .register_notifier = vfio_iommu_type1_register_notifier,
> + .unregister_notifier = vfio_iommu_type1_unregister_notifier,
> };
>
> static int __init vfio_iommu_type1_init(void)
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 0609a2052846..4c91ce8bfaeb 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -80,6 +80,10 @@ struct vfio_iommu_driver_ops {
> unsigned long *phys_pfn);
> long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> long npage);
> + int (*register_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> + int (*unregister_notifier)(void *iommu_data,
> + struct notifier_block *nb);
> };
>
> extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> @@ -137,6 +141,13 @@ extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> long npage);
>
> +#define VFIO_IOMMU_NOTIFY_DMA_UNMAP 1
> +
> +extern int vfio_register_notifier(struct device *dev,
> + struct notifier_block *nb);
> +
> +extern int vfio_unregister_notifier(struct device *dev,
> + struct notifier_block *nb);
> /*
> * IRQfd - generic
> */
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-31 3:50 ` [Qemu-devel] " Jike Song
@ 2016-10-31 5:59 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-31 5:59 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/31/2016 9:20 AM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
>> about DMA_UNMAP.
>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
>> Vendor driver should register notifer using these APIs.
>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
>> mappings.
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
>> ---
>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
>> include/linux/vfio.h | 11 +++++
>> 3 files changed, 163 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
>> index 28b50ca14c52..ff05ac6b1e90 100644
>> --- a/drivers/vfio/vfio.c
>> +++ b/drivers/vfio/vfio.c
>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
>> }
>> EXPORT_SYMBOL(vfio_unpin_pages);
>>
>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
>> +{
>
> Hi Kirti,
>
> Given that below 4 methods are members of vfio_iommu_driver_ops:
>
> pin_pages
> unpin_pages
> register_notifier
> unregister_notifier
>
> the names of exposed VFIO APIs could possibly be clearer:
>
> vfio_iommu_pin_pages
> vfio_iommu_unpin_pages
> vfio_iommu_register_notifier
> vfio_iommu_unreigster_nodier
>
Hey Jike,
I had followed the same style as other members in this structure:
attach_group
detach_group
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-31 5:59 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-10-31 5:59 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/31/2016 9:20 AM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
>> about DMA_UNMAP.
>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
>> Vendor driver should register notifer using these APIs.
>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
>> mappings.
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
>> ---
>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
>> include/linux/vfio.h | 11 +++++
>> 3 files changed, 163 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
>> index 28b50ca14c52..ff05ac6b1e90 100644
>> --- a/drivers/vfio/vfio.c
>> +++ b/drivers/vfio/vfio.c
>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
>> }
>> EXPORT_SYMBOL(vfio_unpin_pages);
>>
>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
>> +{
>
> Hi Kirti,
>
> Given that below 4 methods are members of vfio_iommu_driver_ops:
>
> pin_pages
> unpin_pages
> register_notifier
> unregister_notifier
>
> the names of exposed VFIO APIs could possibly be clearer:
>
> vfio_iommu_pin_pages
> vfio_iommu_unpin_pages
> vfio_iommu_register_notifier
> vfio_iommu_unreigster_nodier
>
Hey Jike,
I had followed the same style as other members in this structure:
attach_group
detach_group
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-31 5:59 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-31 6:05 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-31 6:05 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/31/2016 01:59 PM, Kirti Wankhede wrote:
> On 10/31/2016 9:20 AM, Jike Song wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
>>> about DMA_UNMAP.
>>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
>>> Vendor driver should register notifer using these APIs.
>>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
>>> mappings.
>>>
>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
>>> ---
>>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
>>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
>>> include/linux/vfio.h | 11 +++++
>>> 3 files changed, 163 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
>>> index 28b50ca14c52..ff05ac6b1e90 100644
>>> --- a/drivers/vfio/vfio.c
>>> +++ b/drivers/vfio/vfio.c
>>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
>>> }
>>> EXPORT_SYMBOL(vfio_unpin_pages);
>>>
>>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
>>> +{
>>
>> Hi Kirti,
>>
>> Given that below 4 methods are members of vfio_iommu_driver_ops:
>>
>> pin_pages
>> unpin_pages
>> register_notifier
>> unregister_notifier
>>
>> the names of exposed VFIO APIs could possibly be clearer:
>>
>> vfio_iommu_pin_pages
>> vfio_iommu_unpin_pages
>> vfio_iommu_register_notifier
>> vfio_iommu_unreigster_nodier
>>
>
> Hey Jike,
>
> I had followed the same style as other members in this structure:
>
> attach_group
> detach_group
>
I mean the APIs exposed. For example, vfio_register_notifier() is somehow
by the name too generic to know what it is provided for.
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-10-31 6:05 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-31 6:05 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/31/2016 01:59 PM, Kirti Wankhede wrote:
> On 10/31/2016 9:20 AM, Jike Song wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
>>> about DMA_UNMAP.
>>> Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
>>> Vendor driver should register notifer using these APIs.
>>> Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
>>> mappings.
>>>
>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>> Change-Id: I5910d0024d6be87f3e8d3e0ca0eaeaaa0b17f271
>>> ---
>>> drivers/vfio/vfio.c | 73 +++++++++++++++++++++++++++++++++
>>> drivers/vfio/vfio_iommu_type1.c | 89 ++++++++++++++++++++++++++++++++++++-----
>>> include/linux/vfio.h | 11 +++++
>>> 3 files changed, 163 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
>>> index 28b50ca14c52..ff05ac6b1e90 100644
>>> --- a/drivers/vfio/vfio.c
>>> +++ b/drivers/vfio/vfio.c
>>> @@ -1891,6 +1891,79 @@ err_unpin_pages:
>>> }
>>> EXPORT_SYMBOL(vfio_unpin_pages);
>>>
>>> +int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
>>> +{
>>
>> Hi Kirti,
>>
>> Given that below 4 methods are members of vfio_iommu_driver_ops:
>>
>> pin_pages
>> unpin_pages
>> register_notifier
>> unregister_notifier
>>
>> the names of exposed VFIO APIs could possibly be clearer:
>>
>> vfio_iommu_pin_pages
>> vfio_iommu_unpin_pages
>> vfio_iommu_register_notifier
>> vfio_iommu_unreigster_nodier
>>
>
> Hey Jike,
>
> I had followed the same style as other members in this structure:
>
> attach_group
> detach_group
>
I mean the APIs exposed. For example, vfio_register_notifier() is somehow
by the name too generic to know what it is provided for.
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 18/19] docs: Sysfs ABI for mediated device framework
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-10-31 7:19 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-31 7:19 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added details of sysfs ABI for mediated device framework
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: Icb0fd4ed58a2fa793fbcb1c3d5009a4403c1f3ac
> ---
> Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++++++++++++++++++++++++++
> 1 file changed, 111 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-vfio-mdev b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
> new file mode 100644
> index 000000000000..452dbe39270e
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
> @@ -0,0 +1,111 @@
> +What: /sys/.../<device>/mdev_supported_types/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory contains list of directories of currently
> + supported mediated device types and their details for
> + <device>. Supported type attributes are defined by the
> + vendor driver who registers with Mediated device framework.
> + Each supported type is a directory whose name is created
> + by adding the device driver string as a prefix to the
> + string provided by the vendor driver.
> +
> +What: /sys/.../<device>/mdev_supported_types/<type-id>/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory gives details of supported type, like name,
> + description, available_instances, device_api etc.
> + 'device_api' and 'available_instances' are mandatory
> + attributes to be provided by vendor driver. 'name',
> + 'description' and other vendor driver specific attributes
> + are optional.
> +
Hi Kirti,
Is there any checking in the mdev framework that mandatory attributes
are actually provided?
--
Thanks,
Jike
> +What: /sys/.../mdev_supported_types/<type-id>/create
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Writing UUID to this file will create mediated device of
> + type <type-id> for parent device <device>. This is a
> + write-only file.
> + For example:
> + # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > \
> + /sys/devices/foo/mdev_supported_types/foo-1/create
> +
> +What: /sys/.../mdev_supported_types/<type-id>/devices/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory contains symbolic links pointing to mdev
> + devices sysfs entries which are created of this <type-id>.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/available_instances
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show the number of mediated
> + devices of type <type-id> that can be created. This is a
> + readonly file.
> +Users:
> + Userspace applications interested in creating mediated
> + device of that type. Userspace application should check
> + the number of available instances could be created before
> + creating mediated device of this type.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/device_api
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show VFIO device API supported
> + by this type. For example, "vfio-pci" for a PCI device,
> + "vfio-platform" for platform device.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/name
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show human readable name of the
> + mediated device that will get created of type <type-id>.
> + This is optional attribute. For example: "Grid M60-0Q"
> +Users:
> + Userspace applications interested in knowing the name of
> + a particular <type-id> that can help in understanding the
> + type of mediated device.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/description
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show description of the type of
> + mediated device that will get created of type <type-id>.
> + This is optional attribute. For example:
> + "2 heads, 512M FB, 2560x1600 maximum resolution"
> +Users:
> + Userspace applications interested in knowing the details of
> + a particular <type-id> that can help in understanding the
> + features provided by that type of mediated device.
> +
> +What: /sys/.../<device>/<UUID>/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory represents device directory of mediated
> + device. It contains all the attributes related to mediated
> + device.
> +
> +What: /sys/.../<device>/<UUID>/mdev_type
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This is symbolic link pointing to supported type, <type-id>
> + directory of which this mediated device is created.
> +
> +What: /sys/.../<device>/<UUID>/remove
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Writing '1' to this file destroys the mediated device. The
> + vendor driver can fail the remove() callback if that device
> + is active and the vendor driver doesn't support hot unplug.
> + Example:
> + # echo 1 > /sys/bus/mdev/devices/<UUID>/remove
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 18/19] docs: Sysfs ABI for mediated device framework
@ 2016-10-31 7:19 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-10-31 7:19 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added details of sysfs ABI for mediated device framework
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: Icb0fd4ed58a2fa793fbcb1c3d5009a4403c1f3ac
> ---
> Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++++++++++++++++++++++++++
> 1 file changed, 111 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-vfio-mdev b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
> new file mode 100644
> index 000000000000..452dbe39270e
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
> @@ -0,0 +1,111 @@
> +What: /sys/.../<device>/mdev_supported_types/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory contains list of directories of currently
> + supported mediated device types and their details for
> + <device>. Supported type attributes are defined by the
> + vendor driver who registers with Mediated device framework.
> + Each supported type is a directory whose name is created
> + by adding the device driver string as a prefix to the
> + string provided by the vendor driver.
> +
> +What: /sys/.../<device>/mdev_supported_types/<type-id>/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory gives details of supported type, like name,
> + description, available_instances, device_api etc.
> + 'device_api' and 'available_instances' are mandatory
> + attributes to be provided by vendor driver. 'name',
> + 'description' and other vendor driver specific attributes
> + are optional.
> +
Hi Kirti,
Is there any checking in the mdev framework that mandatory attributes
are actually provided?
--
Thanks,
Jike
> +What: /sys/.../mdev_supported_types/<type-id>/create
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Writing UUID to this file will create mediated device of
> + type <type-id> for parent device <device>. This is a
> + write-only file.
> + For example:
> + # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" > \
> + /sys/devices/foo/mdev_supported_types/foo-1/create
> +
> +What: /sys/.../mdev_supported_types/<type-id>/devices/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory contains symbolic links pointing to mdev
> + devices sysfs entries which are created of this <type-id>.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/available_instances
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show the number of mediated
> + devices of type <type-id> that can be created. This is a
> + readonly file.
> +Users:
> + Userspace applications interested in creating mediated
> + device of that type. Userspace application should check
> + the number of available instances could be created before
> + creating mediated device of this type.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/device_api
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show VFIO device API supported
> + by this type. For example, "vfio-pci" for a PCI device,
> + "vfio-platform" for platform device.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/name
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show human readable name of the
> + mediated device that will get created of type <type-id>.
> + This is optional attribute. For example: "Grid M60-0Q"
> +Users:
> + Userspace applications interested in knowing the name of
> + a particular <type-id> that can help in understanding the
> + type of mediated device.
> +
> +What: /sys/.../mdev_supported_types/<type-id>/description
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Reading this attribute will show description of the type of
> + mediated device that will get created of type <type-id>.
> + This is optional attribute. For example:
> + "2 heads, 512M FB, 2560x1600 maximum resolution"
> +Users:
> + Userspace applications interested in knowing the details of
> + a particular <type-id> that can help in understanding the
> + features provided by that type of mediated device.
> +
> +What: /sys/.../<device>/<UUID>/
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This directory represents device directory of mediated
> + device. It contains all the attributes related to mediated
> + device.
> +
> +What: /sys/.../<device>/<UUID>/mdev_type
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + This is symbolic link pointing to supported type, <type-id>
> + directory of which this mediated device is created.
> +
> +What: /sys/.../<device>/<UUID>/remove
> +Date: October 2016
> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
> +Description:
> + Writing '1' to this file destroys the mediated device. The
> + vendor driver can fail the remove() callback if that device
> + is active and the vendor driver doesn't support hot unplug.
> + Example:
> + # echo 1 > /sys/bus/mdev/devices/<UUID>/remove
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 01/19] vfio: Mediated device Core driver
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-11-01 3:08 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 3:08 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Design for Mediated Device Driver:
> Main purpose of this driver is to provide a common interface for mediated
> device management that can be used by different drivers of different
> devices.
>
> This module provides a generic interface to create the device, add it to
> mediated bus, add device to IOMMU group and then add it to vfio group.
>
> Below is the high Level block diagram, with Nvidia, Intel and IBM devices
> as example, since these are the devices which are going to actively use
> this module as of now.
>
> +---------------+
> | |
> | +-----------+ | mdev_register_driver() +--------------+
> | | | +<------------------------+ __init() |
> | | mdev | | | |
> | | bus | +------------------------>+ |<-> VFIO user
> | | driver | | probe()/remove() | vfio_mdev.ko | APIs
> | | | | | |
> | +-----------+ | +--------------+
> | |
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> | +-----------+ | mdev_register_device() +--------------+
> | | | +<------------------------+ |
> | | | | | nvidia.ko |<-> physical
> | | | +------------------------>+ | device
> | | | | callback +--------------+
> | | Physical | |
> | | device | | mdev_register_device() +--------------+
> | | interface | |<------------------------+ |
> | | | | | i915.ko |<-> physical
> | | | +------------------------>+ | device
> | | | | callback +--------------+
> | | | |
> | | | | mdev_register_device() +--------------+
> | | | +<------------------------+ |
> | | | | | ccw_device.ko|<-> physical
> | | | +------------------------>+ | device
> | | | | callback +--------------+
> | +-----------+ |
> +---------------+
>
> Core driver provides two types of registration interfaces:
> 1. Registration interface for mediated bus driver:
>
> /**
> * struct mdev_driver - Mediated device's driver
> * @name: driver name
> * @probe: called when new device created
> * @remove:called when device removed
> * @driver:device driver structure
> *
> **/
> struct mdev_driver {
> const char *name;
> int (*probe) (struct device *dev);
> void (*remove) (struct device *dev);
> struct device_driver driver;
> };
>
> Mediated bus driver for mdev device should use this interface to register
> and unregister with core driver respectively:
>
> int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
> void mdev_unregister_driver(struct mdev_driver *drv);
>
> Mediated bus driver is responsible to add/delete mediated devices to/from
> VFIO group when devices are bound and unbound to the driver.
>
> 2. Physical device driver interface
> This interface provides vendor driver the set APIs to manage physical
> device related work in its driver. APIs are :
>
> * dev_attr_groups: attributes of the parent device.
> * mdev_attr_groups: attributes of the mediated device.
> * supported_type_groups: attributes to define supported type. This is
> mandatory field.
> * create: to allocate basic resources in vendor driver for a mediated
> device. This is mandatory to be provided by vendor driver.
> * remove: to free resources in vendor driver when mediated device is
> destroyed. This is mandatory to be provided by vendor driver.
> * open: open callback of mediated device
> * release: release callback of mediated device
> * read : read emulation callback.
> * write: write emulation callback.
> * mmap: mmap emulation callback.
> * ioctl: ioctl callback.
>
> Drivers should use these interfaces to register and unregister device to
> mdev core driver respectively:
>
> extern int mdev_register_device(struct device *dev,
> const struct parent_ops *ops);
> extern void mdev_unregister_device(struct device *dev);
>
> There are no locks to serialize above callbacks in mdev driver and
> vfio_mdev driver. If required, vendor driver can have locks to serialize
> above APIs in their driver.
Maybe some information above could be placed under Documentation instead?
It's kind of weird to have the block diagram and interfaces documentation
in the git commit message :-)
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I73a5084574270b14541c529461ea2f03c292d510
> ---
> drivers/vfio/Kconfig | 1 +
> drivers/vfio/Makefile | 1 +
> drivers/vfio/mdev/Kconfig | 10 +
> drivers/vfio/mdev/Makefile | 4 +
> drivers/vfio/mdev/mdev_core.c | 384 +++++++++++++++++++++++++++++++++++++++
> drivers/vfio/mdev/mdev_driver.c | 122 +++++++++++++
> drivers/vfio/mdev/mdev_private.h | 41 +++++
> drivers/vfio/mdev/mdev_sysfs.c | 286 +++++++++++++++++++++++++++++
> include/linux/mdev.h | 167 +++++++++++++++++
> 9 files changed, 1016 insertions(+)
> create mode 100644 drivers/vfio/mdev/Kconfig
> create mode 100644 drivers/vfio/mdev/Makefile
> create mode 100644 drivers/vfio/mdev/mdev_core.c
> create mode 100644 drivers/vfio/mdev/mdev_driver.c
> create mode 100644 drivers/vfio/mdev/mdev_private.h
> create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
> create mode 100644 include/linux/mdev.h
>
> diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
> index da6e2ce77495..23eced02aaf6 100644
> --- a/drivers/vfio/Kconfig
> +++ b/drivers/vfio/Kconfig
> @@ -48,4 +48,5 @@ menuconfig VFIO_NOIOMMU
>
> source "drivers/vfio/pci/Kconfig"
> source "drivers/vfio/platform/Kconfig"
> +source "drivers/vfio/mdev/Kconfig"
> source "virt/lib/Kconfig"
> diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
> index 7b8a31f63fea..4a23c13b6be4 100644
> --- a/drivers/vfio/Makefile
> +++ b/drivers/vfio/Makefile
> @@ -7,3 +7,4 @@ obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
> obj-$(CONFIG_VFIO_SPAPR_EEH) += vfio_spapr_eeh.o
> obj-$(CONFIG_VFIO_PCI) += pci/
> obj-$(CONFIG_VFIO_PLATFORM) += platform/
> +obj-$(CONFIG_VFIO_MDEV) += mdev/
> diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
> new file mode 100644
> index 000000000000..303c14ce2847
> --- /dev/null
> +++ b/drivers/vfio/mdev/Kconfig
> @@ -0,0 +1,10 @@
> +
> +config VFIO_MDEV
> + tristate "Mediated device driver framework"
> + depends on VFIO
> + default n
> + help
> + Provides a framework to virtualize devices.
> + See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
> +
> + If you don't know what do here, say N.
> diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
> new file mode 100644
> index 000000000000..31bc04801d94
> --- /dev/null
> +++ b/drivers/vfio/mdev/Makefile
> @@ -0,0 +1,4 @@
> +
> +mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
> +
> +obj-$(CONFIG_VFIO_MDEV) += mdev.o
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> new file mode 100644
> index 000000000000..9d8fa5c91c2e
> --- /dev/null
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -0,0 +1,384 @@
> +/*
> + * Mediated device Core Driver
> + *
> + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
> + * Author: Neo Jia <cjia@nvidia.com>
> + * Kirti Wankhede <kwankhede@nvidia.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/device.h>
> +#include <linux/slab.h>
> +#include <linux/uuid.h>
> +#include <linux/sysfs.h>
> +#include <linux/mdev.h>
> +
> +#include "mdev_private.h"
> +
> +#define DRIVER_VERSION "0.1"
> +#define DRIVER_AUTHOR "NVIDIA Corporation"
> +#define DRIVER_DESC "Mediated device Core Driver"
> +
> +static LIST_HEAD(parent_list);
> +static DEFINE_MUTEX(parent_list_lock);
> +static struct class_compat *mdev_bus_compat_class;
> +
> +static int _find_mdev_device(struct device *dev, void *data)
> +{
> + struct mdev_device *mdev;
> +
> + if (!dev_is_mdev(dev))
> + return 0;
> +
> + mdev = to_mdev_device(dev);
> +
> + if (uuid_le_cmp(mdev->uuid, *(uuid_le *)data) == 0)
> + return 1;
> +
> + return 0;
> +}
> +
> +static bool mdev_device_exist(struct parent_device *parent, uuid_le uuid)
> +{
> + struct device *dev;
> +
> + dev = device_find_child(parent->dev, &uuid, _find_mdev_device);
'_find_mdev_device' is actually a match, better rename to '__match_mdev' or
something alike.
> + if (dev) {
> + put_device(dev);
> + return true;
> + }
> +
> + return false;
> +}
> +
> +/* Should be called holding parent_list_lock */
> +static struct parent_device *__find_parent_device(struct device *dev)
> +{
> + struct parent_device *parent;
> +
> + list_for_each_entry(parent, &parent_list, next) {
> + if (parent->dev == dev)
> + return parent;
> + }
> + return NULL;
> +}
> +
> +static void mdev_release_parent(struct kref *kref)
> +{
> + struct parent_device *parent = container_of(kref, struct parent_device,
> + ref);
> + struct device *dev = parent->dev;
> +
> + kfree(parent);
> + put_device(dev);
> +}
> +
> +static
> +inline struct parent_device *mdev_get_parent(struct parent_device *parent)
> +{
> + if (parent)
> + kref_get(&parent->ref);
> +
> + return parent;
> +}
> +
> +static inline void mdev_put_parent(struct parent_device *parent)
> +{
> + if (parent)
> + kref_put(&parent->ref, mdev_release_parent);
> +}
> +
> +static int mdev_device_create_ops(struct kobject *kobj,
> + struct mdev_device *mdev)
> +{
> + struct parent_device *parent = mdev->parent;
> + int ret;
> +
> + ret = parent->ops->create(kobj, mdev);
> + if (ret)
> + return ret;
> +
> + ret = sysfs_create_groups(&mdev->dev.kobj,
> + parent->ops->mdev_attr_groups);
> + if (ret)
> + parent->ops->remove(mdev);
> +
> + return ret;
> +}
> +
> +/*
> + * mdev_device_remove_ops gets called from sysfs's 'remove' and when parent
> + * device is being unregistered from mdev device framework.
> + * - 'force_remove' is set to 'false' when called from sysfs's 'remove' which
> + * indicates that if the mdev device is active, used by VMM or userspace
> + * application, vendor driver could return error then don't remove the device.
> + * - 'force_remove' is set to 'true' when called from mdev_unregister_device()
> + * which indicate that parent device is being removed from mdev device
> + * framework so remove mdev device forcefully.
> + */
> +static int mdev_device_remove_ops(struct mdev_device *mdev, bool force_remove)
> +{
> + struct parent_device *parent = mdev->parent;
> + int ret;
> +
> + /*
> + * Vendor driver can return error if VMM or userspace application is
> + * using this mdev device.
> + */
> + ret = parent->ops->remove(mdev);
> + if (ret && !force_remove)
> + return -EBUSY;
> +
> + sysfs_remove_groups(&mdev->dev.kobj, parent->ops->mdev_attr_groups);
> + return 0;
> +}
> +
> +static int mdev_device_remove_cb(struct device *dev, void *data)
> +{
> + if (!dev_is_mdev(dev))
> + return 0;
> +
> + return mdev_device_remove(dev, data ? *(bool *)data : true);
> +}
> +
> +/*
> + * mdev_register_device : Register a device
> + * @dev: device structure representing parent device.
> + * @ops: Parent device operation structure to be registered.
> + *
> + * Add device to list of registered parent devices.
> + * Returns a negative value on error, otherwise 0.
> + */
> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
> +{
> + int ret;
> + struct parent_device *parent;
> +
> + /* check for mandatory ops */
> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
> + return -EINVAL;
> +
> + dev = get_device(dev);
> + if (!dev)
> + return -EINVAL;
> +
> + mutex_lock(&parent_list_lock);
> +
> + /* Check for duplicate */
> + parent = __find_parent_device(dev);
> + if (parent) {
> + ret = -EEXIST;
> + goto add_dev_err;
> + }
> +
> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
> + if (!parent) {
> + ret = -ENOMEM;
> + goto add_dev_err;
> + }
> +
> + kref_init(&parent->ref);
> + mutex_init(&parent->lock);
> +
> + parent->dev = dev;
> + parent->ops = ops;
> +
> + ret = parent_create_sysfs_files(parent);
> + if (ret) {
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> + return ret;
> + }
> +
> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
> + if (ret)
> + dev_warn(dev, "Failed to create compatibility class link\n");
> +
> + list_add(&parent->next, &parent_list);
> + mutex_unlock(&parent_list_lock);
> +
> + dev_info(dev, "MDEV: Registered\n");
> + return 0;
> +
> +add_dev_err:
> + mutex_unlock(&parent_list_lock);
> + put_device(dev);
> + return ret;
> +}
> +EXPORT_SYMBOL(mdev_register_device);
> +
> +/*
> + * mdev_unregister_device : Unregister a parent device
> + * @dev: device structure representing parent device.
> + *
> + * Remove device from list of registered parent devices. Give a chance to free
> + * existing mediated devices for given device.
> + */
> +
> +void mdev_unregister_device(struct device *dev)
> +{
> + struct parent_device *parent;
> + bool force_remove = true;
> +
> + mutex_lock(&parent_list_lock);
> + parent = __find_parent_device(dev);
> +
> + if (!parent) {
> + mutex_unlock(&parent_list_lock);
> + return;
> + }
> + dev_info(dev, "MDEV: Unregistering\n");
> +
> + list_del(&parent->next);
> + class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
> +
> + device_for_each_child(dev, (void *)&force_remove,
> + mdev_device_remove_cb);
> +
> + parent_remove_sysfs_files(parent);
> +
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> +}
> +EXPORT_SYMBOL(mdev_unregister_device);
> +
> +static void mdev_device_release(struct device *dev)
> +{
> + struct mdev_device *mdev = to_mdev_device(dev);
> +
> + dev_dbg(&mdev->dev, "MDEV: destroying\n");
> + kfree(mdev);
> +}
> +
> +int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
> +{
> + int ret;
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type = to_mdev_type(kobj);
> +
> + parent = mdev_get_parent(type->parent);
> + if (!parent)
> + return -EINVAL;
> +
> + mutex_lock(&parent->lock);
> +
> + /* Check for duplicate */
> + if (mdev_device_exist(parent, uuid)) {
> + ret = -EEXIST;
> + goto create_err;
> + }
> +
> + mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> + if (!mdev) {
> + ret = -ENOMEM;
> + goto create_err;
> + }
> +
> + memcpy(&mdev->uuid, &uuid, sizeof(uuid_le));
> + mdev->parent = parent;
> + kref_init(&mdev->ref);
> +
> + mdev->dev.parent = dev;
> + mdev->dev.bus = &mdev_bus_type;
> + mdev->dev.release = mdev_device_release;
> + dev_set_name(&mdev->dev, "%pUl", uuid.b);
> +
> + ret = device_register(&mdev->dev);
> + if (ret) {
> + put_device(&mdev->dev);
> + goto create_err;
> + }
> +
> + ret = mdev_device_create_ops(kobj, mdev);
> + if (ret)
> + goto create_failed;
> +
> + ret = mdev_create_sysfs_files(&mdev->dev, type);
> + if (ret) {
> + mdev_device_remove_ops(mdev, true);
> + goto create_failed;
> + }
> +
> + mdev->type_kobj = kobj;
> + dev_dbg(&mdev->dev, "MDEV: created\n");
> +
> + mutex_unlock(&parent->lock);
> + return ret;
> +
> +create_failed:
> + device_unregister(&mdev->dev);
> +
> +create_err:
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +int mdev_device_remove(struct device *dev, bool force_remove)
> +{
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type;
> + int ret;
> +
> + mdev = to_mdev_device(dev);
> + type = to_mdev_type(mdev->type_kobj);
> + parent = mdev->parent;
> + mutex_lock(&parent->lock);
> +
> + ret = mdev_device_remove_ops(mdev, force_remove);
> + if (ret) {
> + mutex_unlock(&parent->lock);
> + return ret;
> + }
> +
> + mdev_remove_sysfs_files(dev, type);
> + device_unregister(dev);
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +static int __init mdev_init(void)
> +{
> + int ret;
> +
> + ret = mdev_bus_register();
> + if (ret) {
> + pr_err("Failed to register mdev bus\n");
> + return ret;
> + }
> +
> + mdev_bus_compat_class = class_compat_register("mdev_bus");
> + if (!mdev_bus_compat_class) {
> + mdev_bus_unregister();
> + return -ENOMEM;
> + }
> +
> + /*
> + * Attempt to load known vfio_mdev. This gives us a working environment
> + * without the user needing to explicitly load vfio_mdev driver.
> + */
> + request_module_nowait("vfio_mdev");
> +
> + return ret;
> +}
> +
> +static void __exit mdev_exit(void)
> +{
> + class_compat_unregister(mdev_bus_compat_class);
> + mdev_bus_unregister();
> +}
> +
> +module_init(mdev_init)
> +module_exit(mdev_exit)
> +
> +MODULE_VERSION(DRIVER_VERSION);
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR(DRIVER_AUTHOR);
> +MODULE_DESCRIPTION(DRIVER_DESC);
> diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
> new file mode 100644
> index 000000000000..0b3250044a80
> --- /dev/null
> +++ b/drivers/vfio/mdev/mdev_driver.c
> @@ -0,0 +1,122 @@
> +/*
> + * MDEV driver
> + *
> + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
> + * Author: Neo Jia <cjia@nvidia.com>
> + * Kirti Wankhede <kwankhede@nvidia.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/iommu.h>
> +#include <linux/mdev.h>
> +
> +#include "mdev_private.h"
> +
> +static int mdev_attach_iommu(struct mdev_device *mdev)
> +{
> + int ret;
> + struct iommu_group *group;
> +
> + group = iommu_group_alloc();
> + if (IS_ERR(group))
> + return PTR_ERR(group);
Maybe I overthought, but where the iommu_group is released? On successful
return you already have a ref, I didn't find an iommu_group_put after that.
--
Thanks,
Jike
> +
> + ret = iommu_group_add_device(group, &mdev->dev);
> + if (ret)
> + goto attach_fail;
> +
> + dev_info(&mdev->dev, "MDEV: group_id = %d\n",
> + iommu_group_id(group));
> +attach_fail:
> + iommu_group_put(group);
> + return ret;
> +}
> +
> +static void mdev_detach_iommu(struct mdev_device *mdev)
> +{
> + iommu_group_remove_device(&mdev->dev);
> + dev_info(&mdev->dev, "MDEV: detaching iommu\n");
> +}
> +
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-11-01 3:08 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 3:08 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Design for Mediated Device Driver:
> Main purpose of this driver is to provide a common interface for mediated
> device management that can be used by different drivers of different
> devices.
>
> This module provides a generic interface to create the device, add it to
> mediated bus, add device to IOMMU group and then add it to vfio group.
>
> Below is the high Level block diagram, with Nvidia, Intel and IBM devices
> as example, since these are the devices which are going to actively use
> this module as of now.
>
> +---------------+
> | |
> | +-----------+ | mdev_register_driver() +--------------+
> | | | +<------------------------+ __init() |
> | | mdev | | | |
> | | bus | +------------------------>+ |<-> VFIO user
> | | driver | | probe()/remove() | vfio_mdev.ko | APIs
> | | | | | |
> | +-----------+ | +--------------+
> | |
> | MDEV CORE |
> | MODULE |
> | mdev.ko |
> | +-----------+ | mdev_register_device() +--------------+
> | | | +<------------------------+ |
> | | | | | nvidia.ko |<-> physical
> | | | +------------------------>+ | device
> | | | | callback +--------------+
> | | Physical | |
> | | device | | mdev_register_device() +--------------+
> | | interface | |<------------------------+ |
> | | | | | i915.ko |<-> physical
> | | | +------------------------>+ | device
> | | | | callback +--------------+
> | | | |
> | | | | mdev_register_device() +--------------+
> | | | +<------------------------+ |
> | | | | | ccw_device.ko|<-> physical
> | | | +------------------------>+ | device
> | | | | callback +--------------+
> | +-----------+ |
> +---------------+
>
> Core driver provides two types of registration interfaces:
> 1. Registration interface for mediated bus driver:
>
> /**
> * struct mdev_driver - Mediated device's driver
> * @name: driver name
> * @probe: called when new device created
> * @remove:called when device removed
> * @driver:device driver structure
> *
> **/
> struct mdev_driver {
> const char *name;
> int (*probe) (struct device *dev);
> void (*remove) (struct device *dev);
> struct device_driver driver;
> };
>
> Mediated bus driver for mdev device should use this interface to register
> and unregister with core driver respectively:
>
> int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
> void mdev_unregister_driver(struct mdev_driver *drv);
>
> Mediated bus driver is responsible to add/delete mediated devices to/from
> VFIO group when devices are bound and unbound to the driver.
>
> 2. Physical device driver interface
> This interface provides vendor driver the set APIs to manage physical
> device related work in its driver. APIs are :
>
> * dev_attr_groups: attributes of the parent device.
> * mdev_attr_groups: attributes of the mediated device.
> * supported_type_groups: attributes to define supported type. This is
> mandatory field.
> * create: to allocate basic resources in vendor driver for a mediated
> device. This is mandatory to be provided by vendor driver.
> * remove: to free resources in vendor driver when mediated device is
> destroyed. This is mandatory to be provided by vendor driver.
> * open: open callback of mediated device
> * release: release callback of mediated device
> * read : read emulation callback.
> * write: write emulation callback.
> * mmap: mmap emulation callback.
> * ioctl: ioctl callback.
>
> Drivers should use these interfaces to register and unregister device to
> mdev core driver respectively:
>
> extern int mdev_register_device(struct device *dev,
> const struct parent_ops *ops);
> extern void mdev_unregister_device(struct device *dev);
>
> There are no locks to serialize above callbacks in mdev driver and
> vfio_mdev driver. If required, vendor driver can have locks to serialize
> above APIs in their driver.
Maybe some information above could be placed under Documentation instead?
It's kind of weird to have the block diagram and interfaces documentation
in the git commit message :-)
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I73a5084574270b14541c529461ea2f03c292d510
> ---
> drivers/vfio/Kconfig | 1 +
> drivers/vfio/Makefile | 1 +
> drivers/vfio/mdev/Kconfig | 10 +
> drivers/vfio/mdev/Makefile | 4 +
> drivers/vfio/mdev/mdev_core.c | 384 +++++++++++++++++++++++++++++++++++++++
> drivers/vfio/mdev/mdev_driver.c | 122 +++++++++++++
> drivers/vfio/mdev/mdev_private.h | 41 +++++
> drivers/vfio/mdev/mdev_sysfs.c | 286 +++++++++++++++++++++++++++++
> include/linux/mdev.h | 167 +++++++++++++++++
> 9 files changed, 1016 insertions(+)
> create mode 100644 drivers/vfio/mdev/Kconfig
> create mode 100644 drivers/vfio/mdev/Makefile
> create mode 100644 drivers/vfio/mdev/mdev_core.c
> create mode 100644 drivers/vfio/mdev/mdev_driver.c
> create mode 100644 drivers/vfio/mdev/mdev_private.h
> create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
> create mode 100644 include/linux/mdev.h
>
> diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
> index da6e2ce77495..23eced02aaf6 100644
> --- a/drivers/vfio/Kconfig
> +++ b/drivers/vfio/Kconfig
> @@ -48,4 +48,5 @@ menuconfig VFIO_NOIOMMU
>
> source "drivers/vfio/pci/Kconfig"
> source "drivers/vfio/platform/Kconfig"
> +source "drivers/vfio/mdev/Kconfig"
> source "virt/lib/Kconfig"
> diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
> index 7b8a31f63fea..4a23c13b6be4 100644
> --- a/drivers/vfio/Makefile
> +++ b/drivers/vfio/Makefile
> @@ -7,3 +7,4 @@ obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
> obj-$(CONFIG_VFIO_SPAPR_EEH) += vfio_spapr_eeh.o
> obj-$(CONFIG_VFIO_PCI) += pci/
> obj-$(CONFIG_VFIO_PLATFORM) += platform/
> +obj-$(CONFIG_VFIO_MDEV) += mdev/
> diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
> new file mode 100644
> index 000000000000..303c14ce2847
> --- /dev/null
> +++ b/drivers/vfio/mdev/Kconfig
> @@ -0,0 +1,10 @@
> +
> +config VFIO_MDEV
> + tristate "Mediated device driver framework"
> + depends on VFIO
> + default n
> + help
> + Provides a framework to virtualize devices.
> + See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
> +
> + If you don't know what do here, say N.
> diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
> new file mode 100644
> index 000000000000..31bc04801d94
> --- /dev/null
> +++ b/drivers/vfio/mdev/Makefile
> @@ -0,0 +1,4 @@
> +
> +mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
> +
> +obj-$(CONFIG_VFIO_MDEV) += mdev.o
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> new file mode 100644
> index 000000000000..9d8fa5c91c2e
> --- /dev/null
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -0,0 +1,384 @@
> +/*
> + * Mediated device Core Driver
> + *
> + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
> + * Author: Neo Jia <cjia@nvidia.com>
> + * Kirti Wankhede <kwankhede@nvidia.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/device.h>
> +#include <linux/slab.h>
> +#include <linux/uuid.h>
> +#include <linux/sysfs.h>
> +#include <linux/mdev.h>
> +
> +#include "mdev_private.h"
> +
> +#define DRIVER_VERSION "0.1"
> +#define DRIVER_AUTHOR "NVIDIA Corporation"
> +#define DRIVER_DESC "Mediated device Core Driver"
> +
> +static LIST_HEAD(parent_list);
> +static DEFINE_MUTEX(parent_list_lock);
> +static struct class_compat *mdev_bus_compat_class;
> +
> +static int _find_mdev_device(struct device *dev, void *data)
> +{
> + struct mdev_device *mdev;
> +
> + if (!dev_is_mdev(dev))
> + return 0;
> +
> + mdev = to_mdev_device(dev);
> +
> + if (uuid_le_cmp(mdev->uuid, *(uuid_le *)data) == 0)
> + return 1;
> +
> + return 0;
> +}
> +
> +static bool mdev_device_exist(struct parent_device *parent, uuid_le uuid)
> +{
> + struct device *dev;
> +
> + dev = device_find_child(parent->dev, &uuid, _find_mdev_device);
'_find_mdev_device' is actually a match, better rename to '__match_mdev' or
something alike.
> + if (dev) {
> + put_device(dev);
> + return true;
> + }
> +
> + return false;
> +}
> +
> +/* Should be called holding parent_list_lock */
> +static struct parent_device *__find_parent_device(struct device *dev)
> +{
> + struct parent_device *parent;
> +
> + list_for_each_entry(parent, &parent_list, next) {
> + if (parent->dev == dev)
> + return parent;
> + }
> + return NULL;
> +}
> +
> +static void mdev_release_parent(struct kref *kref)
> +{
> + struct parent_device *parent = container_of(kref, struct parent_device,
> + ref);
> + struct device *dev = parent->dev;
> +
> + kfree(parent);
> + put_device(dev);
> +}
> +
> +static
> +inline struct parent_device *mdev_get_parent(struct parent_device *parent)
> +{
> + if (parent)
> + kref_get(&parent->ref);
> +
> + return parent;
> +}
> +
> +static inline void mdev_put_parent(struct parent_device *parent)
> +{
> + if (parent)
> + kref_put(&parent->ref, mdev_release_parent);
> +}
> +
> +static int mdev_device_create_ops(struct kobject *kobj,
> + struct mdev_device *mdev)
> +{
> + struct parent_device *parent = mdev->parent;
> + int ret;
> +
> + ret = parent->ops->create(kobj, mdev);
> + if (ret)
> + return ret;
> +
> + ret = sysfs_create_groups(&mdev->dev.kobj,
> + parent->ops->mdev_attr_groups);
> + if (ret)
> + parent->ops->remove(mdev);
> +
> + return ret;
> +}
> +
> +/*
> + * mdev_device_remove_ops gets called from sysfs's 'remove' and when parent
> + * device is being unregistered from mdev device framework.
> + * - 'force_remove' is set to 'false' when called from sysfs's 'remove' which
> + * indicates that if the mdev device is active, used by VMM or userspace
> + * application, vendor driver could return error then don't remove the device.
> + * - 'force_remove' is set to 'true' when called from mdev_unregister_device()
> + * which indicate that parent device is being removed from mdev device
> + * framework so remove mdev device forcefully.
> + */
> +static int mdev_device_remove_ops(struct mdev_device *mdev, bool force_remove)
> +{
> + struct parent_device *parent = mdev->parent;
> + int ret;
> +
> + /*
> + * Vendor driver can return error if VMM or userspace application is
> + * using this mdev device.
> + */
> + ret = parent->ops->remove(mdev);
> + if (ret && !force_remove)
> + return -EBUSY;
> +
> + sysfs_remove_groups(&mdev->dev.kobj, parent->ops->mdev_attr_groups);
> + return 0;
> +}
> +
> +static int mdev_device_remove_cb(struct device *dev, void *data)
> +{
> + if (!dev_is_mdev(dev))
> + return 0;
> +
> + return mdev_device_remove(dev, data ? *(bool *)data : true);
> +}
> +
> +/*
> + * mdev_register_device : Register a device
> + * @dev: device structure representing parent device.
> + * @ops: Parent device operation structure to be registered.
> + *
> + * Add device to list of registered parent devices.
> + * Returns a negative value on error, otherwise 0.
> + */
> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
> +{
> + int ret;
> + struct parent_device *parent;
> +
> + /* check for mandatory ops */
> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
> + return -EINVAL;
> +
> + dev = get_device(dev);
> + if (!dev)
> + return -EINVAL;
> +
> + mutex_lock(&parent_list_lock);
> +
> + /* Check for duplicate */
> + parent = __find_parent_device(dev);
> + if (parent) {
> + ret = -EEXIST;
> + goto add_dev_err;
> + }
> +
> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
> + if (!parent) {
> + ret = -ENOMEM;
> + goto add_dev_err;
> + }
> +
> + kref_init(&parent->ref);
> + mutex_init(&parent->lock);
> +
> + parent->dev = dev;
> + parent->ops = ops;
> +
> + ret = parent_create_sysfs_files(parent);
> + if (ret) {
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> + return ret;
> + }
> +
> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
> + if (ret)
> + dev_warn(dev, "Failed to create compatibility class link\n");
> +
> + list_add(&parent->next, &parent_list);
> + mutex_unlock(&parent_list_lock);
> +
> + dev_info(dev, "MDEV: Registered\n");
> + return 0;
> +
> +add_dev_err:
> + mutex_unlock(&parent_list_lock);
> + put_device(dev);
> + return ret;
> +}
> +EXPORT_SYMBOL(mdev_register_device);
> +
> +/*
> + * mdev_unregister_device : Unregister a parent device
> + * @dev: device structure representing parent device.
> + *
> + * Remove device from list of registered parent devices. Give a chance to free
> + * existing mediated devices for given device.
> + */
> +
> +void mdev_unregister_device(struct device *dev)
> +{
> + struct parent_device *parent;
> + bool force_remove = true;
> +
> + mutex_lock(&parent_list_lock);
> + parent = __find_parent_device(dev);
> +
> + if (!parent) {
> + mutex_unlock(&parent_list_lock);
> + return;
> + }
> + dev_info(dev, "MDEV: Unregistering\n");
> +
> + list_del(&parent->next);
> + class_compat_remove_link(mdev_bus_compat_class, dev, NULL);
> +
> + device_for_each_child(dev, (void *)&force_remove,
> + mdev_device_remove_cb);
> +
> + parent_remove_sysfs_files(parent);
> +
> + mutex_unlock(&parent_list_lock);
> + mdev_put_parent(parent);
> +}
> +EXPORT_SYMBOL(mdev_unregister_device);
> +
> +static void mdev_device_release(struct device *dev)
> +{
> + struct mdev_device *mdev = to_mdev_device(dev);
> +
> + dev_dbg(&mdev->dev, "MDEV: destroying\n");
> + kfree(mdev);
> +}
> +
> +int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
> +{
> + int ret;
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type = to_mdev_type(kobj);
> +
> + parent = mdev_get_parent(type->parent);
> + if (!parent)
> + return -EINVAL;
> +
> + mutex_lock(&parent->lock);
> +
> + /* Check for duplicate */
> + if (mdev_device_exist(parent, uuid)) {
> + ret = -EEXIST;
> + goto create_err;
> + }
> +
> + mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
> + if (!mdev) {
> + ret = -ENOMEM;
> + goto create_err;
> + }
> +
> + memcpy(&mdev->uuid, &uuid, sizeof(uuid_le));
> + mdev->parent = parent;
> + kref_init(&mdev->ref);
> +
> + mdev->dev.parent = dev;
> + mdev->dev.bus = &mdev_bus_type;
> + mdev->dev.release = mdev_device_release;
> + dev_set_name(&mdev->dev, "%pUl", uuid.b);
> +
> + ret = device_register(&mdev->dev);
> + if (ret) {
> + put_device(&mdev->dev);
> + goto create_err;
> + }
> +
> + ret = mdev_device_create_ops(kobj, mdev);
> + if (ret)
> + goto create_failed;
> +
> + ret = mdev_create_sysfs_files(&mdev->dev, type);
> + if (ret) {
> + mdev_device_remove_ops(mdev, true);
> + goto create_failed;
> + }
> +
> + mdev->type_kobj = kobj;
> + dev_dbg(&mdev->dev, "MDEV: created\n");
> +
> + mutex_unlock(&parent->lock);
> + return ret;
> +
> +create_failed:
> + device_unregister(&mdev->dev);
> +
> +create_err:
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +int mdev_device_remove(struct device *dev, bool force_remove)
> +{
> + struct mdev_device *mdev;
> + struct parent_device *parent;
> + struct mdev_type *type;
> + int ret;
> +
> + mdev = to_mdev_device(dev);
> + type = to_mdev_type(mdev->type_kobj);
> + parent = mdev->parent;
> + mutex_lock(&parent->lock);
> +
> + ret = mdev_device_remove_ops(mdev, force_remove);
> + if (ret) {
> + mutex_unlock(&parent->lock);
> + return ret;
> + }
> +
> + mdev_remove_sysfs_files(dev, type);
> + device_unregister(dev);
> + mutex_unlock(&parent->lock);
> + mdev_put_parent(parent);
> + return ret;
> +}
> +
> +static int __init mdev_init(void)
> +{
> + int ret;
> +
> + ret = mdev_bus_register();
> + if (ret) {
> + pr_err("Failed to register mdev bus\n");
> + return ret;
> + }
> +
> + mdev_bus_compat_class = class_compat_register("mdev_bus");
> + if (!mdev_bus_compat_class) {
> + mdev_bus_unregister();
> + return -ENOMEM;
> + }
> +
> + /*
> + * Attempt to load known vfio_mdev. This gives us a working environment
> + * without the user needing to explicitly load vfio_mdev driver.
> + */
> + request_module_nowait("vfio_mdev");
> +
> + return ret;
> +}
> +
> +static void __exit mdev_exit(void)
> +{
> + class_compat_unregister(mdev_bus_compat_class);
> + mdev_bus_unregister();
> +}
> +
> +module_init(mdev_init)
> +module_exit(mdev_exit)
> +
> +MODULE_VERSION(DRIVER_VERSION);
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR(DRIVER_AUTHOR);
> +MODULE_DESCRIPTION(DRIVER_DESC);
> diff --git a/drivers/vfio/mdev/mdev_driver.c b/drivers/vfio/mdev/mdev_driver.c
> new file mode 100644
> index 000000000000..0b3250044a80
> --- /dev/null
> +++ b/drivers/vfio/mdev/mdev_driver.c
> @@ -0,0 +1,122 @@
> +/*
> + * MDEV driver
> + *
> + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
> + * Author: Neo Jia <cjia@nvidia.com>
> + * Kirti Wankhede <kwankhede@nvidia.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/iommu.h>
> +#include <linux/mdev.h>
> +
> +#include "mdev_private.h"
> +
> +static int mdev_attach_iommu(struct mdev_device *mdev)
> +{
> + int ret;
> + struct iommu_group *group;
> +
> + group = iommu_group_alloc();
> + if (IS_ERR(group))
> + return PTR_ERR(group);
Maybe I overthought, but where the iommu_group is released? On successful
return you already have a ref, I didn't find an iommu_group_put after that.
--
Thanks,
Jike
> +
> + ret = iommu_group_add_device(group, &mdev->dev);
> + if (ret)
> + goto attach_fail;
> +
> + dev_info(&mdev->dev, "MDEV: group_id = %d\n",
> + iommu_group_id(group));
> +attach_fail:
> + iommu_group_put(group);
> + return ret;
> +}
> +
> +static void mdev_detach_iommu(struct mdev_device *mdev)
> +{
> + iommu_group_remove_device(&mdev->dev);
> + dev_info(&mdev->dev, "MDEV: detaching iommu\n");
> +}
> +
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 01/19] vfio: Mediated device Core driver
2016-11-01 3:08 ` [Qemu-devel] " Jike Song
@ 2016-11-01 3:44 ` Alex Williamson
-1 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-11-01 3:44 UTC (permalink / raw)
To: Jike Song
Cc: Kirti Wankhede, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On Tue, 01 Nov 2016 11:08:15 +0800
Jike Song <jike.song@intel.com> wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> > +static int mdev_attach_iommu(struct mdev_device *mdev)
> > +{
> > + int ret;
> > + struct iommu_group *group;
> > +
> > + group = iommu_group_alloc();
> > + if (IS_ERR(group))
> > + return PTR_ERR(group);
>
> Maybe I overthought, but where the iommu_group is released? On successful
> return you already have a ref, I didn't find an iommu_group_put after that.
...
> > +
> > + ret = iommu_group_add_device(group, &mdev->dev);
> > + if (ret)
> > + goto attach_fail;
> > +
> > + dev_info(&mdev->dev, "MDEV: group_id = %d\n",
> > + iommu_group_id(group));
> > +attach_fail:
> > + iommu_group_put(group);
> > + return ret;
> > +}
> > +
> > +static void mdev_detach_iommu(struct mdev_device *mdev)
> > +{
> > + iommu_group_remove_device(&mdev->dev);
Here. Adding a device to the group takes a group reference so we can
'put' the group to release the reference from the alloc as soon as a
device is added. When we remove the device, that reference is removed
and this should result in a release of the group if all other
references are balanced. Thanks,
Alex
> > + dev_info(&mdev->dev, "MDEV: detaching iommu\n");
> > +}
> > +
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-11-01 3:44 ` Alex Williamson
0 siblings, 0 replies; 119+ messages in thread
From: Alex Williamson @ 2016-11-01 3:44 UTC (permalink / raw)
To: Jike Song
Cc: Kirti Wankhede, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On Tue, 01 Nov 2016 11:08:15 +0800
Jike Song <jike.song@intel.com> wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> > +static int mdev_attach_iommu(struct mdev_device *mdev)
> > +{
> > + int ret;
> > + struct iommu_group *group;
> > +
> > + group = iommu_group_alloc();
> > + if (IS_ERR(group))
> > + return PTR_ERR(group);
>
> Maybe I overthought, but where the iommu_group is released? On successful
> return you already have a ref, I didn't find an iommu_group_put after that.
...
> > +
> > + ret = iommu_group_add_device(group, &mdev->dev);
> > + if (ret)
> > + goto attach_fail;
> > +
> > + dev_info(&mdev->dev, "MDEV: group_id = %d\n",
> > + iommu_group_id(group));
> > +attach_fail:
> > + iommu_group_put(group);
> > + return ret;
> > +}
> > +
> > +static void mdev_detach_iommu(struct mdev_device *mdev)
> > +{
> > + iommu_group_remove_device(&mdev->dev);
Here. Adding a device to the group takes a group reference so we can
'put' the group to release the reference from the alloc as soon as a
device is added. When we remove the device, that reference is removed
and this should result in a release of the group if all other
references are balanced. Thanks,
Alex
> > + dev_info(&mdev->dev, "MDEV: detaching iommu\n");
> > +}
> > +
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-29 14:03 ` Alex Williamson
` (2 preceding siblings ...)
(?)
@ 2016-11-01 3:45 ` Dong Jia Shi
-1 siblings, 0 replies; 119+ messages in thread
From: Dong Jia Shi @ 2016-11-01 3:45 UTC (permalink / raw)
To: Alex Williamson
Cc: Jike Song, cjia, kvm, qemu-devel, linux-kernel, kevin.tian,
Kirti Wankhede, kraxel, pbonzini, bjsdjshi
* Alex Williamson <alex.williamson@redhat.com> [2016-10-29 08:03:01 -0600]:
> On Sat, 29 Oct 2016 16:07:05 +0530
> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>
> > On 10/29/2016 2:03 AM, Alex Williamson wrote:
> > > On Sat, 29 Oct 2016 01:32:35 +0530
> > > Kirti Wankhede <kwankhede@nvidia.com> wrote:
> > >
> > >> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> > >>> On Fri, 28 Oct 2016 15:33:58 +0800
> > >>> Jike Song <jike.song@intel.com> wrote:
> > >>>
> > ...
> > >>>>>
> > >>>>> +/*
> > >>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> > >>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> > >>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> > >>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> > >>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> > >>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> > >>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> > >>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
> > >>>>> + * vfio_pfn. In that case, exit from loop.
> > >>>>> + */
> > >>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> > >>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
> > >>>>> +{
> > >>>>> + struct vfio_domain *domain = iommu->external_domain;
> > >>>>> + struct rb_node *n;
> > >>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> > >>>>> +
> > >>>>> + do {
> > >>>>> + prev_vpfn = vpfn;
> > >>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> > >>>>> +
> > >>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
> > >>>>> +
> > >>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
> > >>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> > >>>>> +
> > >>>>> + if ((vpfn->iova >= unmap->iova) &&
> > >>>>> + (vpfn->iova < unmap->iova + unmap->size))
> > >>>>> + break;
> > >>>>> + }
> > >>>>> +
> > >>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> > >>>>> +
> > >>>>> + /* Notify any listeners about DMA_UNMAP */
> > >>>>> + if (vpfn)
> > >>>>> + blocking_notifier_call_chain(&iommu->notifier,
> > >>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> > >>>>> + &vpfn->pfn);
> > >>>>
> > >>>> Hi Kirti,
> > >>>>
> > >>>> The information carried by notifier is only a pfn.
> > >>>>
> > >>>> Since your pin/unpin interfaces design, it's the vendor driver who should
> > >>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
> > >>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> > >>>> for multiple times.
> > >>>>
> > >>>> With the notifier carrying only a pfn, to find the iova by this pfn,
> > >>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
> > >>>> too much.
> > >>>>
> > >>>> Since the vendor could also suffer from IOMMU-compatible problem,
> > >>>> which means a local cache is always helpful, so I'd like to have the
> > >>>> iova carried to the notifier.
> > >>>>
> > >>>> What'd you say?
> > >>>
> > >>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> > >>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> > >>> notifier through to the vendor driver must be based on the same.
> > >>
> > >> Host pfn should be unique, right?
> > >
> > > Let's say a user does a malloc of a single page and does 100 calls to
> > > MAP_DMA populating 100 pages of IOVA space all backed by the same
> > > malloc'd page. This is valid, I have unit tests that do essentially
> > > this. Those will all have the same pfn. The user then does an
> > > UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> > > everything matching that pfn? Of course not, they only unmapped that
> > > one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> > > UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> > > driver MUST therefore also work based on IOVA. This is not an academic
> > > problem, address space aliases exist in real VMs, imagine a virtual
> > > IOMMU. Thanks,
> > >
> >
> >
> > So struct vfio_iommu_type1_dma_unmap should be passed as argument to
> > notifier callback:
> >
> > if (unmapped && iommu->external_domain)
> > - vfio_notifier_call_chain(iommu, unmap);
> > + blocking_notifier_call_chain(&iommu->notifier,
> > + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> > + unmap);
> >
> > Then vendor driver should find pfns he has pinned from this range of
> > iovas, then invalidate and unpin pfns. Right?
>
> That seems like a valid choice. It's probably better than calling the
> notifier for each page of iova. Thanks,
>
> Alex
>
Hi Kirti,
This version requires the *vendor driver* call vfio_register_notifier
for an mdev device before any pinning operations. I guess all of the
vendor drivers may have some alike code for notifier
registration/unregistration.
My question is, how about letting the mdev framework managing the
notifier registration/unregistration process?
We could add a notifier_fn_t callback to "struct parent_ops", then the
mdev framework should make sure that the vendor driver assigned a value
to this callback. The mdev core could initiate a notifier_block for each
parent driver with its callback, and register/unregister it to vfio in
the right time.
--
Dong Jia
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-10-29 14:03 ` Alex Williamson
(?)
(?)
@ 2016-11-01 3:45 ` Dong Jia Shi
2016-11-01 7:47 ` [Qemu-devel] " Kirti Wankhede
-1 siblings, 1 reply; 119+ messages in thread
From: Dong Jia Shi @ 2016-11-01 3:45 UTC (permalink / raw)
To: Alex Williamson
Cc: Kirti Wankhede, Jike Song, pbonzini, kraxel, cjia, qemu-devel,
kvm, kevin.tian, bjsdjshi, linux-kernel
* Alex Williamson <alex.williamson@redhat.com> [2016-10-29 08:03:01 -0600]:
> On Sat, 29 Oct 2016 16:07:05 +0530
> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>
> > On 10/29/2016 2:03 AM, Alex Williamson wrote:
> > > On Sat, 29 Oct 2016 01:32:35 +0530
> > > Kirti Wankhede <kwankhede@nvidia.com> wrote:
> > >
> > >> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> > >>> On Fri, 28 Oct 2016 15:33:58 +0800
> > >>> Jike Song <jike.song@intel.com> wrote:
> > >>>
> > ...
> > >>>>>
> > >>>>> +/*
> > >>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> > >>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> > >>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> > >>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> > >>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> > >>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> > >>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> > >>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
> > >>>>> + * vfio_pfn. In that case, exit from loop.
> > >>>>> + */
> > >>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> > >>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
> > >>>>> +{
> > >>>>> + struct vfio_domain *domain = iommu->external_domain;
> > >>>>> + struct rb_node *n;
> > >>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> > >>>>> +
> > >>>>> + do {
> > >>>>> + prev_vpfn = vpfn;
> > >>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> > >>>>> +
> > >>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
> > >>>>> +
> > >>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
> > >>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> > >>>>> +
> > >>>>> + if ((vpfn->iova >= unmap->iova) &&
> > >>>>> + (vpfn->iova < unmap->iova + unmap->size))
> > >>>>> + break;
> > >>>>> + }
> > >>>>> +
> > >>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> > >>>>> +
> > >>>>> + /* Notify any listeners about DMA_UNMAP */
> > >>>>> + if (vpfn)
> > >>>>> + blocking_notifier_call_chain(&iommu->notifier,
> > >>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> > >>>>> + &vpfn->pfn);
> > >>>>
> > >>>> Hi Kirti,
> > >>>>
> > >>>> The information carried by notifier is only a pfn.
> > >>>>
> > >>>> Since your pin/unpin interfaces design, it's the vendor driver who should
> > >>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
> > >>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> > >>>> for multiple times.
> > >>>>
> > >>>> With the notifier carrying only a pfn, to find the iova by this pfn,
> > >>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
> > >>>> too much.
> > >>>>
> > >>>> Since the vendor could also suffer from IOMMU-compatible problem,
> > >>>> which means a local cache is always helpful, so I'd like to have the
> > >>>> iova carried to the notifier.
> > >>>>
> > >>>> What'd you say?
> > >>>
> > >>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> > >>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> > >>> notifier through to the vendor driver must be based on the same.
> > >>
> > >> Host pfn should be unique, right?
> > >
> > > Let's say a user does a malloc of a single page and does 100 calls to
> > > MAP_DMA populating 100 pages of IOVA space all backed by the same
> > > malloc'd page. This is valid, I have unit tests that do essentially
> > > this. Those will all have the same pfn. The user then does an
> > > UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> > > everything matching that pfn? Of course not, they only unmapped that
> > > one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> > > UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> > > driver MUST therefore also work based on IOVA. This is not an academic
> > > problem, address space aliases exist in real VMs, imagine a virtual
> > > IOMMU. Thanks,
> > >
> >
> >
> > So struct vfio_iommu_type1_dma_unmap should be passed as argument to
> > notifier callback:
> >
> > if (unmapped && iommu->external_domain)
> > - vfio_notifier_call_chain(iommu, unmap);
> > + blocking_notifier_call_chain(&iommu->notifier,
> > + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> > + unmap);
> >
> > Then vendor driver should find pfns he has pinned from this range of
> > iovas, then invalidate and unpin pfns. Right?
>
> That seems like a valid choice. It's probably better than calling the
> notifier for each page of iova. Thanks,
>
> Alex
>
Hi Kirti,
This version requires the *vendor driver* call vfio_register_notifier
for an mdev device before any pinning operations. I guess all of the
vendor drivers may have some alike code for notifier
registration/unregistration.
My question is, how about letting the mdev framework managing the
notifier registration/unregistration process?
We could add a notifier_fn_t callback to "struct parent_ops", then the
mdev framework should make sure that the vendor driver assigned a value
to this callback. The mdev core could initiate a notifier_block for each
parent driver with its callback, and register/unregister it to vfio in
the right time.
--
Dong Jia
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 01/19] vfio: Mediated device Core driver
2016-11-01 3:44 ` [Qemu-devel] " Alex Williamson
@ 2016-11-01 5:28 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 5:28 UTC (permalink / raw)
To: Alex Williamson
Cc: Kirti Wankhede, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 11/01/2016 11:44 AM, Alex Williamson wrote:
> On Tue, 01 Nov 2016 11:08:15 +0800
> Jike Song <jike.song@intel.com> wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> +static int mdev_attach_iommu(struct mdev_device *mdev)
>>> +{
>>> + int ret;
>>> + struct iommu_group *group;
>>> +
>>> + group = iommu_group_alloc();
>>> + if (IS_ERR(group))
>>> + return PTR_ERR(group);
>>
>> Maybe I overthought, but where the iommu_group is released? On successful
>> return you already have a ref, I didn't find an iommu_group_put after that.
> ...
>>> +
>>> + ret = iommu_group_add_device(group, &mdev->dev);
>>> + if (ret)
>>> + goto attach_fail;
>>> +
>>> + dev_info(&mdev->dev, "MDEV: group_id = %d\n",
>>> + iommu_group_id(group));
>>> +attach_fail:
>>> + iommu_group_put(group);
>>> + return ret;
>>> +}
>>> +
>>> +static void mdev_detach_iommu(struct mdev_device *mdev)
>>> +{
>>> + iommu_group_remove_device(&mdev->dev);
>
> Here. Adding a device to the group takes a group reference so we can
> 'put' the group to release the reference from the alloc as soon as a
> device is added. When we remove the device, that reference is removed
> and this should result in a release of the group if all other
> references are balanced. Thanks,
Now I understand, thanks :)
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-11-01 5:28 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 5:28 UTC (permalink / raw)
To: Alex Williamson
Cc: Kirti Wankhede, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 11/01/2016 11:44 AM, Alex Williamson wrote:
> On Tue, 01 Nov 2016 11:08:15 +0800
> Jike Song <jike.song@intel.com> wrote:
>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>> +static int mdev_attach_iommu(struct mdev_device *mdev)
>>> +{
>>> + int ret;
>>> + struct iommu_group *group;
>>> +
>>> + group = iommu_group_alloc();
>>> + if (IS_ERR(group))
>>> + return PTR_ERR(group);
>>
>> Maybe I overthought, but where the iommu_group is released? On successful
>> return you already have a ref, I didn't find an iommu_group_put after that.
> ...
>>> +
>>> + ret = iommu_group_add_device(group, &mdev->dev);
>>> + if (ret)
>>> + goto attach_fail;
>>> +
>>> + dev_info(&mdev->dev, "MDEV: group_id = %d\n",
>>> + iommu_group_id(group));
>>> +attach_fail:
>>> + iommu_group_put(group);
>>> + return ret;
>>> +}
>>> +
>>> +static void mdev_detach_iommu(struct mdev_device *mdev)
>>> +{
>>> + iommu_group_remove_device(&mdev->dev);
>
> Here. Adding a device to the group takes a group reference so we can
> 'put' the group to release the reference from the alloc as soon as a
> device is added. When we remove the device, that reference is removed
> and this should result in a release of the group if all other
> references are balanced. Thanks,
Now I understand, thanks :)
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-11-01 3:45 ` [Qemu-devel] " Dong Jia Shi
@ 2016-11-01 7:47 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-01 7:47 UTC (permalink / raw)
To: Alex Williamson, Jike Song, pbonzini, kraxel, cjia, qemu-devel,
kvm, kevin.tian, bjsdjshi, linux-kernel
On 11/1/2016 9:15 AM, Dong Jia Shi wrote:
> * Alex Williamson <alex.williamson@redhat.com> [2016-10-29 08:03:01 -0600]:
>
>> On Sat, 29 Oct 2016 16:07:05 +0530
>> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>>
>>> On 10/29/2016 2:03 AM, Alex Williamson wrote:
>>>> On Sat, 29 Oct 2016 01:32:35 +0530
>>>> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>>>>
>>>>> On 10/28/2016 6:10 PM, Alex Williamson wrote:
>>>>>> On Fri, 28 Oct 2016 15:33:58 +0800
>>>>>> Jike Song <jike.song@intel.com> wrote:
>>>>>>
>>> ...
>>>>>>>>
>>>>>>>> +/*
>>>>>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>>>>>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>>>>>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>>>>>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>>>>>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>>>>>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>>>>>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>>>>>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
>>>>>>>> + * vfio_pfn. In that case, exit from loop.
>>>>>>>> + */
>>>>>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>>>>>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
>>>>>>>> +{
>>>>>>>> + struct vfio_domain *domain = iommu->external_domain;
>>>>>>>> + struct rb_node *n;
>>>>>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>>>>>>>> +
>>>>>>>> + do {
>>>>>>>> + prev_vpfn = vpfn;
>>>>>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>>>>>>>> +
>>>>>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
>>>>>>>> +
>>>>>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
>>>>>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>>>>>>>> +
>>>>>>>> + if ((vpfn->iova >= unmap->iova) &&
>>>>>>>> + (vpfn->iova < unmap->iova + unmap->size))
>>>>>>>> + break;
>>>>>>>> + }
>>>>>>>> +
>>>>>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>>>>>>>> +
>>>>>>>> + /* Notify any listeners about DMA_UNMAP */
>>>>>>>> + if (vpfn)
>>>>>>>> + blocking_notifier_call_chain(&iommu->notifier,
>>>>>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>>>>>>> + &vpfn->pfn);
>>>>>>>
>>>>>>> Hi Kirti,
>>>>>>>
>>>>>>> The information carried by notifier is only a pfn.
>>>>>>>
>>>>>>> Since your pin/unpin interfaces design, it's the vendor driver who should
>>>>>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
>>>>>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
>>>>>>> for multiple times.
>>>>>>>
>>>>>>> With the notifier carrying only a pfn, to find the iova by this pfn,
>>>>>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
>>>>>>> too much.
>>>>>>>
>>>>>>> Since the vendor could also suffer from IOMMU-compatible problem,
>>>>>>> which means a local cache is always helpful, so I'd like to have the
>>>>>>> iova carried to the notifier.
>>>>>>>
>>>>>>> What'd you say?
>>>>>>
>>>>>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
>>>>>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
>>>>>> notifier through to the vendor driver must be based on the same.
>>>>>
>>>>> Host pfn should be unique, right?
>>>>
>>>> Let's say a user does a malloc of a single page and does 100 calls to
>>>> MAP_DMA populating 100 pages of IOVA space all backed by the same
>>>> malloc'd page. This is valid, I have unit tests that do essentially
>>>> this. Those will all have the same pfn. The user then does an
>>>> UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
>>>> everything matching that pfn? Of course not, they only unmapped that
>>>> one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
>>>> UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
>>>> driver MUST therefore also work based on IOVA. This is not an academic
>>>> problem, address space aliases exist in real VMs, imagine a virtual
>>>> IOMMU. Thanks,
>>>>
>>>
>>>
>>> So struct vfio_iommu_type1_dma_unmap should be passed as argument to
>>> notifier callback:
>>>
>>> if (unmapped && iommu->external_domain)
>>> - vfio_notifier_call_chain(iommu, unmap);
>>> + blocking_notifier_call_chain(&iommu->notifier,
>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>> + unmap);
>>>
>>> Then vendor driver should find pfns he has pinned from this range of
>>> iovas, then invalidate and unpin pfns. Right?
>>
>> That seems like a valid choice. It's probably better than calling the
>> notifier for each page of iova. Thanks,
>>
>> Alex
>>
> Hi Kirti,
>
> This version requires the *vendor driver* call vfio_register_notifier
> for an mdev device before any pinning operations. I guess all of the
> vendor drivers may have some alike code for notifier
> registration/unregistration.
>
> My question is, how about letting the mdev framework managing the
> notifier registration/unregistration process?
>
> We could add a notifier_fn_t callback to "struct parent_ops", then the
> mdev framework should make sure that the vendor driver assigned a value
> to this callback. The mdev core could initiate a notifier_block for each
> parent driver with its callback, and register/unregister it to vfio in
> the right time.
>
Module mdev_core is independent of VFIO so far and it should be
independent of VFIO module.
Its a good suggestion to have a notifier callback in parent_ops, but we
shouldn't call vfio_register_notifier()/ vfio_unregister_notifier() from
mdev core module. vfio_mdev module would take care to
register/unregister notifier to vfio from its vfio_mdev_open()/
vfio_mdev_release() call. That looks cleaner to me.
Notifier callback in parent_ops should be optional since all vendor
drivers might not pin/unpin pages, for example sample mtty driver.
Notifier would be registered to vfio module only if the notifier
callback is provided by vendor driver.
If this looks reasonable, I'll have this patch in my next version of
patch series.
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
@ 2016-11-01 7:47 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-01 7:47 UTC (permalink / raw)
To: Alex Williamson, Jike Song, pbonzini, kraxel, cjia, qemu-devel,
kvm, kevin.tian, bjsdjshi, linux-kernel
On 11/1/2016 9:15 AM, Dong Jia Shi wrote:
> * Alex Williamson <alex.williamson@redhat.com> [2016-10-29 08:03:01 -0600]:
>
>> On Sat, 29 Oct 2016 16:07:05 +0530
>> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>>
>>> On 10/29/2016 2:03 AM, Alex Williamson wrote:
>>>> On Sat, 29 Oct 2016 01:32:35 +0530
>>>> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>>>>
>>>>> On 10/28/2016 6:10 PM, Alex Williamson wrote:
>>>>>> On Fri, 28 Oct 2016 15:33:58 +0800
>>>>>> Jike Song <jike.song@intel.com> wrote:
>>>>>>
>>> ...
>>>>>>>>
>>>>>>>> +/*
>>>>>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
>>>>>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
>>>>>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
>>>>>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
>>>>>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
>>>>>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
>>>>>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
>>>>>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
>>>>>>>> + * vfio_pfn. In that case, exit from loop.
>>>>>>>> + */
>>>>>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
>>>>>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
>>>>>>>> +{
>>>>>>>> + struct vfio_domain *domain = iommu->external_domain;
>>>>>>>> + struct rb_node *n;
>>>>>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
>>>>>>>> +
>>>>>>>> + do {
>>>>>>>> + prev_vpfn = vpfn;
>>>>>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
>>>>>>>> +
>>>>>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
>>>>>>>> +
>>>>>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
>>>>>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
>>>>>>>> +
>>>>>>>> + if ((vpfn->iova >= unmap->iova) &&
>>>>>>>> + (vpfn->iova < unmap->iova + unmap->size))
>>>>>>>> + break;
>>>>>>>> + }
>>>>>>>> +
>>>>>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
>>>>>>>> +
>>>>>>>> + /* Notify any listeners about DMA_UNMAP */
>>>>>>>> + if (vpfn)
>>>>>>>> + blocking_notifier_call_chain(&iommu->notifier,
>>>>>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>>>>>>> + &vpfn->pfn);
>>>>>>>
>>>>>>> Hi Kirti,
>>>>>>>
>>>>>>> The information carried by notifier is only a pfn.
>>>>>>>
>>>>>>> Since your pin/unpin interfaces design, it's the vendor driver who should
>>>>>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
>>>>>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
>>>>>>> for multiple times.
>>>>>>>
>>>>>>> With the notifier carrying only a pfn, to find the iova by this pfn,
>>>>>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
>>>>>>> too much.
>>>>>>>
>>>>>>> Since the vendor could also suffer from IOMMU-compatible problem,
>>>>>>> which means a local cache is always helpful, so I'd like to have the
>>>>>>> iova carried to the notifier.
>>>>>>>
>>>>>>> What'd you say?
>>>>>>
>>>>>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
>>>>>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
>>>>>> notifier through to the vendor driver must be based on the same.
>>>>>
>>>>> Host pfn should be unique, right?
>>>>
>>>> Let's say a user does a malloc of a single page and does 100 calls to
>>>> MAP_DMA populating 100 pages of IOVA space all backed by the same
>>>> malloc'd page. This is valid, I have unit tests that do essentially
>>>> this. Those will all have the same pfn. The user then does an
>>>> UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
>>>> everything matching that pfn? Of course not, they only unmapped that
>>>> one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
>>>> UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
>>>> driver MUST therefore also work based on IOVA. This is not an academic
>>>> problem, address space aliases exist in real VMs, imagine a virtual
>>>> IOMMU. Thanks,
>>>>
>>>
>>>
>>> So struct vfio_iommu_type1_dma_unmap should be passed as argument to
>>> notifier callback:
>>>
>>> if (unmapped && iommu->external_domain)
>>> - vfio_notifier_call_chain(iommu, unmap);
>>> + blocking_notifier_call_chain(&iommu->notifier,
>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
>>> + unmap);
>>>
>>> Then vendor driver should find pfns he has pinned from this range of
>>> iovas, then invalidate and unpin pfns. Right?
>>
>> That seems like a valid choice. It's probably better than calling the
>> notifier for each page of iova. Thanks,
>>
>> Alex
>>
> Hi Kirti,
>
> This version requires the *vendor driver* call vfio_register_notifier
> for an mdev device before any pinning operations. I guess all of the
> vendor drivers may have some alike code for notifier
> registration/unregistration.
>
> My question is, how about letting the mdev framework managing the
> notifier registration/unregistration process?
>
> We could add a notifier_fn_t callback to "struct parent_ops", then the
> mdev framework should make sure that the vendor driver assigned a value
> to this callback. The mdev core could initiate a notifier_block for each
> parent driver with its callback, and register/unregister it to vfio in
> the right time.
>
Module mdev_core is independent of VFIO so far and it should be
independent of VFIO module.
Its a good suggestion to have a notifier callback in parent_ops, but we
shouldn't call vfio_register_notifier()/ vfio_unregister_notifier() from
mdev core module. vfio_mdev module would take care to
register/unregister notifier to vfio from its vfio_mdev_open()/
vfio_mdev_release() call. That looks cleaner to me.
Notifier callback in parent_ops should be optional since all vendor
drivers might not pin/unpin pages, for example sample mtty driver.
Notifier would be registered to vfio module only if the notifier
callback is provided by vendor driver.
If this looks reasonable, I'll have this patch in my next version of
patch series.
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 05/19] vfio iommu: Added pin and unpin callback functions to vfio_iommu_driver_ops
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-11-01 8:07 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 8:07 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added two new callback functions to struct vfio_iommu_driver_ops. Backend
> IOMMU module that supports pining and unpinning pages for mdev devices
> should provide these functions.
> Added APIs for pining and unpining pages to VFIO module. These calls back
> into backend iommu module to actually pin and unpin pages.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: Ia7417723aaae86bec2959ad9ae6c2915ddd340e0
> ---
> drivers/vfio/vfio.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/vfio.h | 12 ++++++-
> 2 files changed, 103 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 2e83bdf007fe..28b50ca14c52 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1799,6 +1799,98 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
> }
> EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
>
> +
> +/*
> + * Pin a set of guest PFNs and return their associated host PFNs for local
> + * domain only.
> + * @dev [in] : device
> + * @user_pfn [in]: array of user/guest PFNs
> + * @npage [in]: count of array elements
> + * @prot [in] : protection flags
> + * @phys_pfn[out] : array of host PFNs
> + */
Hi Kirti,
Would you also add the documentation what the return value is? It's kind
not clear, and any reason to use long instead of int?
> +long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> + long npage, int prot, unsigned long *phys_pfn)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !user_pfn || !phys_pfn)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_pin_pages;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->pin_pages))
> + ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
> + npage, prot, phys_pfn);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_pin_pages:
> + vfio_group_put(group);
> + return ret;
> +
> +}
> +EXPORT_SYMBOL(vfio_pin_pages);
> +
> +/*
> + * Unpin set of host PFNs for local domain only.
> + * @dev [in] : device
> + * @pfn [in] : array of host PFNs to be unpinned.
> + * @npage [in] :count of elements in array, that is number of pages.
> + */
Ditto
--
Thanks,
Jike
> +long vfio_unpin_pages(struct device *dev, unsigned long *pfn, long npage)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !pfn)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_unpin_pages;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->unpin_pages))
> + ret = driver->ops->unpin_pages(container->iommu_data, pfn,
> + npage);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_unpin_pages:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_unpin_pages);
> +
> /**
> * Module/class support
> */
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 0ecae0b1cd34..0609a2052846 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -75,7 +75,11 @@ struct vfio_iommu_driver_ops {
> struct iommu_group *group);
> void (*detach_group)(void *iommu_data,
> struct iommu_group *group);
> -
> + long (*pin_pages)(void *iommu_data, unsigned long *user_pfn,
> + long npage, int prot,
> + unsigned long *phys_pfn);
> + long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> + long npage);
> };
>
> extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> @@ -127,6 +131,12 @@ static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
> }
> #endif /* CONFIG_EEH */
>
> +extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> + long npage, int prot, unsigned long *phys_pfn);
> +
> +extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> + long npage);
> +
> /*
> * IRQfd - generic
> */
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 05/19] vfio iommu: Added pin and unpin callback functions to vfio_iommu_driver_ops
@ 2016-11-01 8:07 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 8:07 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Added two new callback functions to struct vfio_iommu_driver_ops. Backend
> IOMMU module that supports pining and unpinning pages for mdev devices
> should provide these functions.
> Added APIs for pining and unpining pages to VFIO module. These calls back
> into backend iommu module to actually pin and unpin pages.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: Ia7417723aaae86bec2959ad9ae6c2915ddd340e0
> ---
> drivers/vfio/vfio.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/vfio.h | 12 ++++++-
> 2 files changed, 103 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 2e83bdf007fe..28b50ca14c52 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1799,6 +1799,98 @@ void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
> }
> EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
>
> +
> +/*
> + * Pin a set of guest PFNs and return their associated host PFNs for local
> + * domain only.
> + * @dev [in] : device
> + * @user_pfn [in]: array of user/guest PFNs
> + * @npage [in]: count of array elements
> + * @prot [in] : protection flags
> + * @phys_pfn[out] : array of host PFNs
> + */
Hi Kirti,
Would you also add the documentation what the return value is? It's kind
not clear, and any reason to use long instead of int?
> +long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> + long npage, int prot, unsigned long *phys_pfn)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !user_pfn || !phys_pfn)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_pin_pages;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->pin_pages))
> + ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
> + npage, prot, phys_pfn);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_pin_pages:
> + vfio_group_put(group);
> + return ret;
> +
> +}
> +EXPORT_SYMBOL(vfio_pin_pages);
> +
> +/*
> + * Unpin set of host PFNs for local domain only.
> + * @dev [in] : device
> + * @pfn [in] : array of host PFNs to be unpinned.
> + * @npage [in] :count of elements in array, that is number of pages.
> + */
Ditto
--
Thanks,
Jike
> +long vfio_unpin_pages(struct device *dev, unsigned long *pfn, long npage)
> +{
> + struct vfio_container *container;
> + struct vfio_group *group;
> + struct vfio_iommu_driver *driver;
> + ssize_t ret;
> +
> + if (!dev || !pfn)
> + return -EINVAL;
> +
> + group = vfio_group_get_from_dev(dev);
> + if (IS_ERR(group))
> + return PTR_ERR(group);
> +
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + goto err_unpin_pages;
> +
> + container = group->container;
> + down_read(&container->group_lock);
> +
> + driver = container->iommu_driver;
> + if (likely(driver && driver->ops->unpin_pages))
> + ret = driver->ops->unpin_pages(container->iommu_data, pfn,
> + npage);
> + else
> + ret = -EINVAL;
> +
> + up_read(&container->group_lock);
> + vfio_group_try_dissolve_container(group);
> +
> +err_unpin_pages:
> + vfio_group_put(group);
> + return ret;
> +}
> +EXPORT_SYMBOL(vfio_unpin_pages);
> +
> /**
> * Module/class support
> */
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 0ecae0b1cd34..0609a2052846 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -75,7 +75,11 @@ struct vfio_iommu_driver_ops {
> struct iommu_group *group);
> void (*detach_group)(void *iommu_data,
> struct iommu_group *group);
> -
> + long (*pin_pages)(void *iommu_data, unsigned long *user_pfn,
> + long npage, int prot,
> + unsigned long *phys_pfn);
> + long (*unpin_pages)(void *iommu_data, unsigned long *pfn,
> + long npage);
> };
>
> extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
> @@ -127,6 +131,12 @@ static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
> }
> #endif /* CONFIG_EEH */
>
> +extern long vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> + long npage, int prot, unsigned long *phys_pfn);
> +
> +extern long vfio_unpin_pages(struct device *dev, unsigned long *pfn,
> + long npage);
> +
> /*
> * IRQfd - generic
> */
>
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 00/19] Add Mediated device support
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-11-01 8:32 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 8:32 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> This series adds Mediated device support to Linux host kernel. Purpose
> of this series is to provide a common interface for mediated device
> management that can be used by different devices. This series introduces
> Mdev core module that creates and manages mediated devices, VFIO based
> driver for mediated devices that are created by mdev core module and
> update VFIO type1 IOMMU module to support pinning & unpinning for mediated
> devices.
>
> What changed in v10?
> vfio:
> - Split commits in multple individual commits.
> - Removed the function added in v9 to get device_api string.
> - Defined constant strings in include/uapi/linux/vfio.h that should be used by
> vendor driver for device_api attribute.
>
> vfio_iommu_type1:
> - Fixed accounting when pass through device is unplugged while mdev device
> exist in a domain.
> - Added blocking notifier to notify DMA_UNMAP to vendor driver to invalidate
> mappings.
> - Exported APIs to register notifier for DMA_UNMAP action.
>
> Documentation:
> - Added sysfs ABI for mediated device framework.
> - Updated Documentation/vfio-mdev/vfio-mediated-device.txt.
> - Updated mtty.c with bug fixes.
>
> Kirti Wankhede (19):
> vfio: Mediated device Core driver
> vfio: VFIO based driver for Mediated devices
> vfio: Rearrange functions to get vfio_group from dev
> vfio: Common function to increment container_users
> vfio iommu: Added pin and unpin callback functions to
> vfio_iommu_driver_ops
> vfio iommu type1: Update arguments of vfio_lock_acct
> vfio iommu type1: Update argument of vaddr_get_pfn()
> vfio iommu type1: Add find_iommu_group() function
> vfio iommu type1: Add support for mediated devices
> vfio iommu: Add blocking notifier to notify DMA_UNMAP
> vfio: Introduce common function to add capabilities
> vfio_pci: Update vfio_pci to use vfio_info_add_capability()
> vfio: Introduce vfio_set_irqs_validate_and_prepare()
> vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
> vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
> vfio: Define device_api strings
> docs: Add Documentation for Mediated devices
> docs: Sysfs ABI for mediated device framework
> docs: Sample driver to demonstrate how to use Mediated device
> framework.
>
> Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++
> Documentation/vfio-mdev/Makefile | 13 +
> Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
> Documentation/vfio-mdev/vfio-mediated-device.txt | 398 ++++++
> drivers/vfio/Kconfig | 1 +
> drivers/vfio/Makefile | 1 +
> drivers/vfio/mdev/Kconfig | 17 +
> drivers/vfio/mdev/Makefile | 5 +
> drivers/vfio/mdev/mdev_core.c | 384 ++++++
> drivers/vfio/mdev/mdev_driver.c | 122 ++
> drivers/vfio/mdev/mdev_private.h | 41 +
> drivers/vfio/mdev/mdev_sysfs.c | 286 ++++
> drivers/vfio/mdev/vfio_mdev.c | 148 +++
> drivers/vfio/pci/vfio_pci.c | 78 +-
> drivers/vfio/platform/vfio_platform_common.c | 31 +-
> drivers/vfio/vfio.c | 322 ++++-
> drivers/vfio/vfio_iommu_type1.c | 808 ++++++++++--
> include/linux/mdev.h | 167 +++
> include/linux/vfio.h | 30 +-
> include/uapi/linux/vfio.h | 10 +
> 20 files changed, 4270 insertions(+), 206 deletions(-)
> create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
> create mode 100644 Documentation/vfio-mdev/Makefile
> create mode 100644 Documentation/vfio-mdev/mtty.c
> create mode 100644 Documentation/vfio-mdev/vfio-mediated-device.txt
> create mode 100644 drivers/vfio/mdev/Kconfig
> create mode 100644 drivers/vfio/mdev/Makefile
> create mode 100644 drivers/vfio/mdev/mdev_core.c
> create mode 100644 drivers/vfio/mdev/mdev_driver.c
> create mode 100644 drivers/vfio/mdev/mdev_private.h
> create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
> create mode 100644 drivers/vfio/mdev/vfio_mdev.c
> create mode 100644 include/linux/mdev.h
A side note:
I rebased KVMGT upon v10, with 2 minor changes:
1, get_user_pages_remote has only 7 args
2, vfio iommu notifier calls vendor callback with iova instead of pfn
so far it works pretty well. Thanks!
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 00/19] Add Mediated device support
@ 2016-11-01 8:32 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-01 8:32 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> This series adds Mediated device support to Linux host kernel. Purpose
> of this series is to provide a common interface for mediated device
> management that can be used by different devices. This series introduces
> Mdev core module that creates and manages mediated devices, VFIO based
> driver for mediated devices that are created by mdev core module and
> update VFIO type1 IOMMU module to support pinning & unpinning for mediated
> devices.
>
> What changed in v10?
> vfio:
> - Split commits in multple individual commits.
> - Removed the function added in v9 to get device_api string.
> - Defined constant strings in include/uapi/linux/vfio.h that should be used by
> vendor driver for device_api attribute.
>
> vfio_iommu_type1:
> - Fixed accounting when pass through device is unplugged while mdev device
> exist in a domain.
> - Added blocking notifier to notify DMA_UNMAP to vendor driver to invalidate
> mappings.
> - Exported APIs to register notifier for DMA_UNMAP action.
>
> Documentation:
> - Added sysfs ABI for mediated device framework.
> - Updated Documentation/vfio-mdev/vfio-mediated-device.txt.
> - Updated mtty.c with bug fixes.
>
> Kirti Wankhede (19):
> vfio: Mediated device Core driver
> vfio: VFIO based driver for Mediated devices
> vfio: Rearrange functions to get vfio_group from dev
> vfio: Common function to increment container_users
> vfio iommu: Added pin and unpin callback functions to
> vfio_iommu_driver_ops
> vfio iommu type1: Update arguments of vfio_lock_acct
> vfio iommu type1: Update argument of vaddr_get_pfn()
> vfio iommu type1: Add find_iommu_group() function
> vfio iommu type1: Add support for mediated devices
> vfio iommu: Add blocking notifier to notify DMA_UNMAP
> vfio: Introduce common function to add capabilities
> vfio_pci: Update vfio_pci to use vfio_info_add_capability()
> vfio: Introduce vfio_set_irqs_validate_and_prepare()
> vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
> vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
> vfio: Define device_api strings
> docs: Add Documentation for Mediated devices
> docs: Sysfs ABI for mediated device framework
> docs: Sample driver to demonstrate how to use Mediated device
> framework.
>
> Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++
> Documentation/vfio-mdev/Makefile | 13 +
> Documentation/vfio-mdev/mtty.c | 1503 ++++++++++++++++++++++
> Documentation/vfio-mdev/vfio-mediated-device.txt | 398 ++++++
> drivers/vfio/Kconfig | 1 +
> drivers/vfio/Makefile | 1 +
> drivers/vfio/mdev/Kconfig | 17 +
> drivers/vfio/mdev/Makefile | 5 +
> drivers/vfio/mdev/mdev_core.c | 384 ++++++
> drivers/vfio/mdev/mdev_driver.c | 122 ++
> drivers/vfio/mdev/mdev_private.h | 41 +
> drivers/vfio/mdev/mdev_sysfs.c | 286 ++++
> drivers/vfio/mdev/vfio_mdev.c | 148 +++
> drivers/vfio/pci/vfio_pci.c | 78 +-
> drivers/vfio/platform/vfio_platform_common.c | 31 +-
> drivers/vfio/vfio.c | 322 ++++-
> drivers/vfio/vfio_iommu_type1.c | 808 ++++++++++--
> include/linux/mdev.h | 167 +++
> include/linux/vfio.h | 30 +-
> include/uapi/linux/vfio.h | 10 +
> 20 files changed, 4270 insertions(+), 206 deletions(-)
> create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
> create mode 100644 Documentation/vfio-mdev/Makefile
> create mode 100644 Documentation/vfio-mdev/mtty.c
> create mode 100644 Documentation/vfio-mdev/vfio-mediated-device.txt
> create mode 100644 drivers/vfio/mdev/Kconfig
> create mode 100644 drivers/vfio/mdev/Makefile
> create mode 100644 drivers/vfio/mdev/mdev_core.c
> create mode 100644 drivers/vfio/mdev/mdev_driver.c
> create mode 100644 drivers/vfio/mdev/mdev_private.h
> create mode 100644 drivers/vfio/mdev/mdev_sysfs.c
> create mode 100644 drivers/vfio/mdev/vfio_mdev.c
> create mode 100644 include/linux/mdev.h
A side note:
I rebased KVMGT upon v10, with 2 minor changes:
1, get_user_pages_remote has only 7 args
2, vfio iommu notifier calls vendor callback with iova instead of pfn
so far it works pretty well. Thanks!
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-11-01 7:47 ` [Qemu-devel] " Kirti Wankhede
(?)
(?)
@ 2016-11-01 8:33 ` Dong Jia Shi
-1 siblings, 0 replies; 119+ messages in thread
From: Dong Jia Shi @ 2016-11-01 8:33 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Jike Song, cjia, kvm, qemu-devel, linux-kernel, kevin.tian,
Alex Williamson, kraxel, pbonzini, bjsdjshi
* Kirti Wankhede <kwankhede@nvidia.com> [2016-11-01 13:17:19 +0530]:
>
>
> On 11/1/2016 9:15 AM, Dong Jia Shi wrote:
> > * Alex Williamson <alex.williamson@redhat.com> [2016-10-29 08:03:01 -0600]:
> >
> >> On Sat, 29 Oct 2016 16:07:05 +0530
> >> Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >>
> >>> On 10/29/2016 2:03 AM, Alex Williamson wrote:
> >>>> On Sat, 29 Oct 2016 01:32:35 +0530
> >>>> Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >>>>
> >>>>> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> >>>>>> On Fri, 28 Oct 2016 15:33:58 +0800
> >>>>>> Jike Song <jike.song@intel.com> wrote:
> >>>>>>
> >>> ...
> >>>>>>>>
> >>>>>>>> +/*
> >>>>>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> >>>>>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> >>>>>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> >>>>>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> >>>>>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> >>>>>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> >>>>>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> >>>>>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
> >>>>>>>> + * vfio_pfn. In that case, exit from loop.
> >>>>>>>> + */
> >>>>>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> >>>>>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
> >>>>>>>> +{
> >>>>>>>> + struct vfio_domain *domain = iommu->external_domain;
> >>>>>>>> + struct rb_node *n;
> >>>>>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> >>>>>>>> +
> >>>>>>>> + do {
> >>>>>>>> + prev_vpfn = vpfn;
> >>>>>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> >>>>>>>> +
> >>>>>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
> >>>>>>>> +
> >>>>>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
> >>>>>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> >>>>>>>> +
> >>>>>>>> + if ((vpfn->iova >= unmap->iova) &&
> >>>>>>>> + (vpfn->iova < unmap->iova + unmap->size))
> >>>>>>>> + break;
> >>>>>>>> + }
> >>>>>>>> +
> >>>>>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> >>>>>>>> +
> >>>>>>>> + /* Notify any listeners about DMA_UNMAP */
> >>>>>>>> + if (vpfn)
> >>>>>>>> + blocking_notifier_call_chain(&iommu->notifier,
> >>>>>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>>>>>>> + &vpfn->pfn);
> >>>>>>>
> >>>>>>> Hi Kirti,
> >>>>>>>
> >>>>>>> The information carried by notifier is only a pfn.
> >>>>>>>
> >>>>>>> Since your pin/unpin interfaces design, it's the vendor driver who should
> >>>>>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
> >>>>>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> >>>>>>> for multiple times.
> >>>>>>>
> >>>>>>> With the notifier carrying only a pfn, to find the iova by this pfn,
> >>>>>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
> >>>>>>> too much.
> >>>>>>>
> >>>>>>> Since the vendor could also suffer from IOMMU-compatible problem,
> >>>>>>> which means a local cache is always helpful, so I'd like to have the
> >>>>>>> iova carried to the notifier.
> >>>>>>>
> >>>>>>> What'd you say?
> >>>>>>
> >>>>>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> >>>>>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> >>>>>> notifier through to the vendor driver must be based on the same.
> >>>>>
> >>>>> Host pfn should be unique, right?
> >>>>
> >>>> Let's say a user does a malloc of a single page and does 100 calls to
> >>>> MAP_DMA populating 100 pages of IOVA space all backed by the same
> >>>> malloc'd page. This is valid, I have unit tests that do essentially
> >>>> this. Those will all have the same pfn. The user then does an
> >>>> UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> >>>> everything matching that pfn? Of course not, they only unmapped that
> >>>> one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> >>>> UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> >>>> driver MUST therefore also work based on IOVA. This is not an academic
> >>>> problem, address space aliases exist in real VMs, imagine a virtual
> >>>> IOMMU. Thanks,
> >>>>
> >>>
> >>>
> >>> So struct vfio_iommu_type1_dma_unmap should be passed as argument to
> >>> notifier callback:
> >>>
> >>> if (unmapped && iommu->external_domain)
> >>> - vfio_notifier_call_chain(iommu, unmap);
> >>> + blocking_notifier_call_chain(&iommu->notifier,
> >>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>> + unmap);
> >>>
> >>> Then vendor driver should find pfns he has pinned from this range of
> >>> iovas, then invalidate and unpin pfns. Right?
> >>
> >> That seems like a valid choice. It's probably better than calling the
> >> notifier for each page of iova. Thanks,
> >>
> >> Alex
> >>
> > Hi Kirti,
> >
> > This version requires the *vendor driver* call vfio_register_notifier
> > for an mdev device before any pinning operations. I guess all of the
> > vendor drivers may have some alike code for notifier
> > registration/unregistration.
> >
> > My question is, how about letting the mdev framework managing the
> > notifier registration/unregistration process?
> >
> > We could add a notifier_fn_t callback to "struct parent_ops", then the
> > mdev framework should make sure that the vendor driver assigned a value
> > to this callback. The mdev core could initiate a notifier_block for each
> > parent driver with its callback, and register/unregister it to vfio in
> > the right time.
> >
>
> Module mdev_core is independent of VFIO so far and it should be
> independent of VFIO module.
>
> Its a good suggestion to have a notifier callback in parent_ops, but we
> shouldn't call vfio_register_notifier()/ vfio_unregister_notifier() from
> mdev core module. vfio_mdev module would take care to
> register/unregister notifier to vfio from its vfio_mdev_open()/
> vfio_mdev_release() call. That looks cleaner to me.
Nod.
>
> Notifier callback in parent_ops should be optional since all vendor
> drivers might not pin/unpin pages, for example sample mtty driver.
> Notifier would be registered to vfio module only if the notifier
> callback is provided by vendor driver.
>
> If this looks reasonable, I'll have this patch in my next version of
> patch series.
Sounds reasonable for me. Thanks,
>
> Thanks,
> Kirti
>
--
Dong Jia
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP
2016-11-01 7:47 ` [Qemu-devel] " Kirti Wankhede
(?)
@ 2016-11-01 8:33 ` Dong Jia Shi
-1 siblings, 0 replies; 119+ messages in thread
From: Dong Jia Shi @ 2016-11-01 8:33 UTC (permalink / raw)
To: Kirti Wankhede
Cc: Alex Williamson, Jike Song, pbonzini, kraxel, cjia, qemu-devel,
kvm, kevin.tian, bjsdjshi, linux-kernel
* Kirti Wankhede <kwankhede@nvidia.com> [2016-11-01 13:17:19 +0530]:
>
>
> On 11/1/2016 9:15 AM, Dong Jia Shi wrote:
> > * Alex Williamson <alex.williamson@redhat.com> [2016-10-29 08:03:01 -0600]:
> >
> >> On Sat, 29 Oct 2016 16:07:05 +0530
> >> Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >>
> >>> On 10/29/2016 2:03 AM, Alex Williamson wrote:
> >>>> On Sat, 29 Oct 2016 01:32:35 +0530
> >>>> Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >>>>
> >>>>> On 10/28/2016 6:10 PM, Alex Williamson wrote:
> >>>>>> On Fri, 28 Oct 2016 15:33:58 +0800
> >>>>>> Jike Song <jike.song@intel.com> wrote:
> >>>>>>
> >>> ...
> >>>>>>>>
> >>>>>>>> +/*
> >>>>>>>> + * This function finds pfn in domain->external_addr_space->pfn_list for given
> >>>>>>>> + * iova range. If pfn exist, notify pfn to registered notifier list. On
> >>>>>>>> + * receiving notifier callback, vendor driver should invalidate the mapping and
> >>>>>>>> + * call vfio_unpin_pages() to unpin this pfn. With that vfio_pfn for this pfn
> >>>>>>>> + * gets removed from rb tree of pfn_list. That re-arranges rb tree, so while
> >>>>>>>> + * searching for next vfio_pfn in rb tree, start search from first node again.
> >>>>>>>> + * If any vendor driver doesn't unpin that pfn, vfio_pfn would not get removed
> >>>>>>>> + * from rb tree and so in next search vfio_pfn would be same as previous
> >>>>>>>> + * vfio_pfn. In that case, exit from loop.
> >>>>>>>> + */
> >>>>>>>> +static void vfio_notifier_call_chain(struct vfio_iommu *iommu,
> >>>>>>>> + struct vfio_iommu_type1_dma_unmap *unmap)
> >>>>>>>> +{
> >>>>>>>> + struct vfio_domain *domain = iommu->external_domain;
> >>>>>>>> + struct rb_node *n;
> >>>>>>>> + struct vfio_pfn *vpfn = NULL, *prev_vpfn;
> >>>>>>>> +
> >>>>>>>> + do {
> >>>>>>>> + prev_vpfn = vpfn;
> >>>>>>>> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> >>>>>>>> +
> >>>>>>>> + n = rb_first(&domain->external_addr_space->pfn_list);
> >>>>>>>> +
> >>>>>>>> + for (; n; n = rb_next(n), vpfn = NULL) {
> >>>>>>>> + vpfn = rb_entry(n, struct vfio_pfn, node);
> >>>>>>>> +
> >>>>>>>> + if ((vpfn->iova >= unmap->iova) &&
> >>>>>>>> + (vpfn->iova < unmap->iova + unmap->size))
> >>>>>>>> + break;
> >>>>>>>> + }
> >>>>>>>> +
> >>>>>>>> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> >>>>>>>> +
> >>>>>>>> + /* Notify any listeners about DMA_UNMAP */
> >>>>>>>> + if (vpfn)
> >>>>>>>> + blocking_notifier_call_chain(&iommu->notifier,
> >>>>>>>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>>>>>>> + &vpfn->pfn);
> >>>>>>>
> >>>>>>> Hi Kirti,
> >>>>>>>
> >>>>>>> The information carried by notifier is only a pfn.
> >>>>>>>
> >>>>>>> Since your pin/unpin interfaces design, it's the vendor driver who should
> >>>>>>> guarantee pin/unpin same times. To achieve that, the vendor driver must
> >>>>>>> cache it's iova->pfn mapping on its side, to avoid pinning a same page
> >>>>>>> for multiple times.
> >>>>>>>
> >>>>>>> With the notifier carrying only a pfn, to find the iova by this pfn,
> >>>>>>> the vendor driver must *also* keep a reverse-mapping. That's a bit
> >>>>>>> too much.
> >>>>>>>
> >>>>>>> Since the vendor could also suffer from IOMMU-compatible problem,
> >>>>>>> which means a local cache is always helpful, so I'd like to have the
> >>>>>>> iova carried to the notifier.
> >>>>>>>
> >>>>>>> What'd you say?
> >>>>>>
> >>>>>> I agree, the pfn is not unique, multiple guest pfns (iovas) might be
> >>>>>> backed by the same host pfn. DMA_UNMAP calls are based on iova, the
> >>>>>> notifier through to the vendor driver must be based on the same.
> >>>>>
> >>>>> Host pfn should be unique, right?
> >>>>
> >>>> Let's say a user does a malloc of a single page and does 100 calls to
> >>>> MAP_DMA populating 100 pages of IOVA space all backed by the same
> >>>> malloc'd page. This is valid, I have unit tests that do essentially
> >>>> this. Those will all have the same pfn. The user then does an
> >>>> UNMAP_DMA to a single one of those IOVA pages. Did the user unmap
> >>>> everything matching that pfn? Of course not, they only unmapped that
> >>>> one IOVA page. There is no guarantee of a 1:1 mapping of pfn to IOVA.
> >>>> UNMAP_DMA works based on IOVA. Invalidation broadcasts to the vendor
> >>>> driver MUST therefore also work based on IOVA. This is not an academic
> >>>> problem, address space aliases exist in real VMs, imagine a virtual
> >>>> IOMMU. Thanks,
> >>>>
> >>>
> >>>
> >>> So struct vfio_iommu_type1_dma_unmap should be passed as argument to
> >>> notifier callback:
> >>>
> >>> if (unmapped && iommu->external_domain)
> >>> - vfio_notifier_call_chain(iommu, unmap);
> >>> + blocking_notifier_call_chain(&iommu->notifier,
> >>> + VFIO_IOMMU_NOTIFY_DMA_UNMAP,
> >>> + unmap);
> >>>
> >>> Then vendor driver should find pfns he has pinned from this range of
> >>> iovas, then invalidate and unpin pfns. Right?
> >>
> >> That seems like a valid choice. It's probably better than calling the
> >> notifier for each page of iova. Thanks,
> >>
> >> Alex
> >>
> > Hi Kirti,
> >
> > This version requires the *vendor driver* call vfio_register_notifier
> > for an mdev device before any pinning operations. I guess all of the
> > vendor drivers may have some alike code for notifier
> > registration/unregistration.
> >
> > My question is, how about letting the mdev framework managing the
> > notifier registration/unregistration process?
> >
> > We could add a notifier_fn_t callback to "struct parent_ops", then the
> > mdev framework should make sure that the vendor driver assigned a value
> > to this callback. The mdev core could initiate a notifier_block for each
> > parent driver with its callback, and register/unregister it to vfio in
> > the right time.
> >
>
> Module mdev_core is independent of VFIO so far and it should be
> independent of VFIO module.
>
> Its a good suggestion to have a notifier callback in parent_ops, but we
> shouldn't call vfio_register_notifier()/ vfio_unregister_notifier() from
> mdev core module. vfio_mdev module would take care to
> register/unregister notifier to vfio from its vfio_mdev_open()/
> vfio_mdev_release() call. That looks cleaner to me.
Nod.
>
> Notifier callback in parent_ops should be optional since all vendor
> drivers might not pin/unpin pages, for example sample mtty driver.
> Notifier would be registered to vfio module only if the notifier
> callback is provided by vendor driver.
>
> If this looks reasonable, I'll have this patch in my next version of
> patch series.
Sounds reasonable for me. Thanks,
>
> Thanks,
> Kirti
>
--
Dong Jia
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 00/19] Add Mediated device support
2016-11-01 8:32 ` [Qemu-devel] " Jike Song
@ 2016-11-01 15:24 ` Gerd Hoffmann
-1 siblings, 0 replies; 119+ messages in thread
From: Gerd Hoffmann @ 2016-11-01 15:24 UTC (permalink / raw)
To: Jike Song
Cc: Kirti Wankhede, alex.williamson, pbonzini, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
Hi,
> I rebased KVMGT upon v10, with 2 minor changes:
>
> 1, get_user_pages_remote has only 7 args
Appears to be a 4.9 merge window change. v10 as-is applies and builds
fine against 4.8, after rebasing to 4.9-rc3 it stops building due to
this.
Can you share the patch?
> 2, vfio iommu notifier calls vendor callback with iova instead of pfn
And this one too?
Also: github seems to have the v9 kvmgt version still. Can you push
the update?
The kvmgt branch apparently depends on alot of unmerged stuff, "git
describe" says 1669 patches on top of 4.8-rc8.
Can you outline what this is? Mostly drm-next?
How much of this landed in the 4.9 merge window?
thanks,
Gerd
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 00/19] Add Mediated device support
@ 2016-11-01 15:24 ` Gerd Hoffmann
0 siblings, 0 replies; 119+ messages in thread
From: Gerd Hoffmann @ 2016-11-01 15:24 UTC (permalink / raw)
To: Jike Song
Cc: Kirti Wankhede, alex.williamson, pbonzini, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
Hi,
> I rebased KVMGT upon v10, with 2 minor changes:
>
> 1, get_user_pages_remote has only 7 args
Appears to be a 4.9 merge window change. v10 as-is applies and builds
fine against 4.8, after rebasing to 4.9-rc3 it stops building due to
this.
Can you share the patch?
> 2, vfio iommu notifier calls vendor callback with iova instead of pfn
And this one too?
Also: github seems to have the v9 kvmgt version still. Can you push
the update?
The kvmgt branch apparently depends on alot of unmerged stuff, "git
describe" says 1669 patches on top of 4.8-rc8.
Can you outline what this is? Mostly drm-next?
How much of this landed in the 4.9 merge window?
thanks,
Gerd
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 00/19] Add Mediated device support
2016-11-01 15:24 ` [Qemu-devel] " Gerd Hoffmann
(?)
@ 2016-11-02 1:01 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 1:01 UTC (permalink / raw)
To: Gerd Hoffmann
Cc: kevin.tian, cjia, kvm, linux-kernel, alex.williamson, qemu-devel,
Kirti Wankhede, pbonzini, bjsdjshi
On 11/01/2016 11:24 PM, Gerd Hoffmann wrote:
>> I rebased KVMGT upon v10, with 2 minor changes:
>>
>> 1, get_user_pages_remote has only 7 args
>
> Appears to be a 4.9 merge window change. v10 as-is applies and builds
> fine against 4.8, after rebasing to 4.9-rc3 it stops building due to
> this.
>
> Can you share the patch?
>
>> 2, vfio iommu notifier calls vendor callback with iova instead of pfn
>
> And this one too?
>
> Also: github seems to have the v9 kvmgt version still. Can you push
> the update?
Zhenyu will help to push it to 01org/gvt-linux. Those 2 patches added by
me are trivial, I guess Kirti will have her formal fixes in next version.
> The kvmgt branch apparently depends on alot of unmerged stuff, "git
> describe" says 1669 patches on top of 4.8-rc8.
>
> Can you outline what this is? Mostly drm-next?
> How much of this landed in the 4.9 merge window?
Yes, mostly drm-next, targeting 4.10 merge window. The overwhelming
part is the device-model under drivers/gpu/drm/i915/gvt/.
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 18/19] docs: Sysfs ABI for mediated device framework
2016-10-31 7:19 ` [Qemu-devel] " Jike Song
@ 2016-11-02 7:55 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-02 7:55 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/31/2016 12:49 PM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> Added details of sysfs ABI for mediated device framework
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Change-Id: Icb0fd4ed58a2fa793fbcb1c3d5009a4403c1f3ac
>> ---
>> Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++++++++++++++++++++++++++
>> 1 file changed, 111 insertions(+)
>> create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
>>
>> diff --git a/Documentation/ABI/testing/sysfs-bus-vfio-mdev b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
>> new file mode 100644
>> index 000000000000..452dbe39270e
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
>> @@ -0,0 +1,111 @@
>> +What: /sys/.../<device>/mdev_supported_types/
>> +Date: October 2016
>> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
>> +Description:
>> + This directory contains list of directories of currently
>> + supported mediated device types and their details for
>> + <device>. Supported type attributes are defined by the
>> + vendor driver who registers with Mediated device framework.
>> + Each supported type is a directory whose name is created
>> + by adding the device driver string as a prefix to the
>> + string provided by the vendor driver.
>> +
>> +What: /sys/.../<device>/mdev_supported_types/<type-id>/
>> +Date: October 2016
>> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
>> +Description:
>> + This directory gives details of supported type, like name,
>> + description, available_instances, device_api etc.
>> + 'device_api' and 'available_instances' are mandatory
>> + attributes to be provided by vendor driver. 'name',
>> + 'description' and other vendor driver specific attributes
>> + are optional.
>> +
>
> Hi Kirti,
>
> Is there any checking in the mdev framework that mandatory attributes
> are actually provided?
>
No. These are exposed so that libvirt can use those to create devices.
If those are not provided, libvirt would not work.
Kirti.
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 18/19] docs: Sysfs ABI for mediated device framework
@ 2016-11-02 7:55 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-02 7:55 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/31/2016 12:49 PM, Jike Song wrote:
> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>> Added details of sysfs ABI for mediated device framework
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Change-Id: Icb0fd4ed58a2fa793fbcb1c3d5009a4403c1f3ac
>> ---
>> Documentation/ABI/testing/sysfs-bus-vfio-mdev | 111 ++++++++++++++++++++++++++
>> 1 file changed, 111 insertions(+)
>> create mode 100644 Documentation/ABI/testing/sysfs-bus-vfio-mdev
>>
>> diff --git a/Documentation/ABI/testing/sysfs-bus-vfio-mdev b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
>> new file mode 100644
>> index 000000000000..452dbe39270e
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-bus-vfio-mdev
>> @@ -0,0 +1,111 @@
>> +What: /sys/.../<device>/mdev_supported_types/
>> +Date: October 2016
>> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
>> +Description:
>> + This directory contains list of directories of currently
>> + supported mediated device types and their details for
>> + <device>. Supported type attributes are defined by the
>> + vendor driver who registers with Mediated device framework.
>> + Each supported type is a directory whose name is created
>> + by adding the device driver string as a prefix to the
>> + string provided by the vendor driver.
>> +
>> +What: /sys/.../<device>/mdev_supported_types/<type-id>/
>> +Date: October 2016
>> +Contact: Kirti Wankhede <kwankhede@nvidia.com>
>> +Description:
>> + This directory gives details of supported type, like name,
>> + description, available_instances, device_api etc.
>> + 'device_api' and 'available_instances' are mandatory
>> + attributes to be provided by vendor driver. 'name',
>> + 'description' and other vendor driver specific attributes
>> + are optional.
>> +
>
> Hi Kirti,
>
> Is there any checking in the mdev framework that mandatory attributes
> are actually provided?
>
No. These are exposed so that libvirt can use those to create devices.
If those are not provided, libvirt would not work.
Kirti.
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 01/19] vfio: Mediated device Core driver
2016-10-29 18:11 ` [Qemu-devel] " Jike Song
@ 2016-11-02 7:59 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-02 7:59 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/29/2016 11:41 PM, Jike Song wrote:
> On 10/29/2016 06:06 PM, Kirti Wankhede wrote:
>>
>>
>> On 10/29/2016 10:00 AM, Jike Song wrote:
>>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>>> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
>>>> +{
>>>> + int ret;
>>>> + struct parent_device *parent;
>>>> +
>>>> + /* check for mandatory ops */
>>>> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
>>>> + return -EINVAL;
>>>> +
>>>> + dev = get_device(dev);
>>>> + if (!dev)
>>>> + return -EINVAL;
>>>> +
>>>> + mutex_lock(&parent_list_lock);
>>>> +
>>>> + /* Check for duplicate */
>>>> + parent = __find_parent_device(dev);
>>>> + if (parent) {
>>>> + ret = -EEXIST;
>>>> + goto add_dev_err;
>>>> + }
>>>> +
>>>> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
>>>> + if (!parent) {
>>>> + ret = -ENOMEM;
>>>> + goto add_dev_err;
>>>> + }
>>>> +
>>>> + kref_init(&parent->ref);
>>>> + mutex_init(&parent->lock);
>>>> +
>>>> + parent->dev = dev;
>>>> + parent->ops = ops;
>>>> +
>>>> + ret = parent_create_sysfs_files(parent);
>>>> + if (ret) {
>>>> + mutex_unlock(&parent_list_lock);
>>>> + mdev_put_parent(parent);
>>>> + return ret;
>>>> + }
>>>> +
>>>> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
>>>> + if (ret)
>>>> + dev_warn(dev, "Failed to create compatibility class link\n");
>>>> +
>>>
>>> Hi Kirti,
>>>
>>> Like I replied to previous version:
>>>
>>> http://www.spinics.net/lists/kvm/msg139331.html
>>>
>>
>> Hi Jike,
>>
>> I saw your reply but by that time v10 version of patch series was out
>> for review.
>>
>
> Ah..yes, I forgot that :)
>
>>> You can always check if mdev_bus_compat_class already registered
>>> here, and register it if not yet. Same logic should be adopted to
>>> mdev_init.
>>>
>>> Current implementation will simply panic if configured as builtin,
>>> which is rare but far from impossible.
>>>
>>
>> Can you verify attached patch with v10 patch-set whether this works for you?
>> I'll incorporate this change in my next version.
>>
>
> Seems cool. But would you please also keep the register in mdev_init(),
> just check the 'in case it was already registered' case? Thanks!
>
The class is used only to keep symbolic to the devices which are
registered to mdev framework. So I think its ok to register this class
when first device is registered.
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
@ 2016-11-02 7:59 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-02 7:59 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/29/2016 11:41 PM, Jike Song wrote:
> On 10/29/2016 06:06 PM, Kirti Wankhede wrote:
>>
>>
>> On 10/29/2016 10:00 AM, Jike Song wrote:
>>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>>> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
>>>> +{
>>>> + int ret;
>>>> + struct parent_device *parent;
>>>> +
>>>> + /* check for mandatory ops */
>>>> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
>>>> + return -EINVAL;
>>>> +
>>>> + dev = get_device(dev);
>>>> + if (!dev)
>>>> + return -EINVAL;
>>>> +
>>>> + mutex_lock(&parent_list_lock);
>>>> +
>>>> + /* Check for duplicate */
>>>> + parent = __find_parent_device(dev);
>>>> + if (parent) {
>>>> + ret = -EEXIST;
>>>> + goto add_dev_err;
>>>> + }
>>>> +
>>>> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
>>>> + if (!parent) {
>>>> + ret = -ENOMEM;
>>>> + goto add_dev_err;
>>>> + }
>>>> +
>>>> + kref_init(&parent->ref);
>>>> + mutex_init(&parent->lock);
>>>> +
>>>> + parent->dev = dev;
>>>> + parent->ops = ops;
>>>> +
>>>> + ret = parent_create_sysfs_files(parent);
>>>> + if (ret) {
>>>> + mutex_unlock(&parent_list_lock);
>>>> + mdev_put_parent(parent);
>>>> + return ret;
>>>> + }
>>>> +
>>>> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
>>>> + if (ret)
>>>> + dev_warn(dev, "Failed to create compatibility class link\n");
>>>> +
>>>
>>> Hi Kirti,
>>>
>>> Like I replied to previous version:
>>>
>>> http://www.spinics.net/lists/kvm/msg139331.html
>>>
>>
>> Hi Jike,
>>
>> I saw your reply but by that time v10 version of patch series was out
>> for review.
>>
>
> Ah..yes, I forgot that :)
>
>>> You can always check if mdev_bus_compat_class already registered
>>> here, and register it if not yet. Same logic should be adopted to
>>> mdev_init.
>>>
>>> Current implementation will simply panic if configured as builtin,
>>> which is rare but far from impossible.
>>>
>>
>> Can you verify attached patch with v10 patch-set whether this works for you?
>> I'll incorporate this change in my next version.
>>
>
> Seems cool. But would you please also keep the register in mdev_init(),
> just check the 'in case it was already registered' case? Thanks!
>
The class is used only to keep symbolic to the devices which are
registered to mdev framework. So I think its ok to register this class
when first device is registered.
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
2016-10-28 6:01 ` [Qemu-devel] " Jike Song
@ 2016-11-02 8:06 ` Kirti Wankhede
-1 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-02 8:06 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/28/2016 11:31 AM, Jike Song wrote:
> On 10/27/2016 08:24 PM, Kirti Wankhede wrote:
>>
>>
>> On 10/27/2016 5:41 PM, Jike Song wrote:
>>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
>>>> argument.
>>>>
>>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
>>>> ---
>>>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
>>>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>>>> index 72fee415044a..3d916b965492 100644
>>>> --- a/drivers/vfio/vfio_iommu_type1.c
>>>> +++ b/drivers/vfio/vfio_iommu_type1.c
>>>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
>>>> return 0;
>>>> }
>>>>
>>>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>>>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
>>>> + int prot, unsigned long *pfn)
>>>> {
>>>> struct page *page[1];
>>>> struct vm_area_struct *vma;
>>>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
>>>> int ret = -EFAULT;
>>>>
>>>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
>>>> + if (remote_mm) {
>>>> + down_read(&mm->mmap_sem);
>>>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
>>>> + !!(prot & IOMMU_WRITE), 0, page, NULL);
>>>
>>> Hi Kirti,
>>>
>>> It seems that get_user_pages_remote has only 7 args but you somehow gives 8
>>> here?
>>>
>>
>> I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c:
>>
>> long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
>> unsigned long start, unsigned long nr_pages,
>> int write, int force, struct page **pages,
>> struct vm_area_struct **vmas)
>> {
>> return __get_user_pages_locked(tsk, mm, start, nr_pages, write,
>> force,
>> pages, vmas, NULL, false,
>> FOLL_TOUCH | FOLL_REMOTE);
>> }
>> EXPORT_SYMBOL(get_user_pages_remote);
>
> It's queer. I checked:
>
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/mm/gup.c
>
> It still has 7 args.
>
> I believe you have seen this change somewhere, would you share the repo url
> and branch name of the linux-next you based on?
>
Sorry, my git was synced just few changes behind this change. I'll make
sure that I test the patch set at top of tree.
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn()
@ 2016-11-02 8:06 ` Kirti Wankhede
0 siblings, 0 replies; 119+ messages in thread
From: Kirti Wankhede @ 2016-11-02 8:06 UTC (permalink / raw)
To: Jike Song
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/28/2016 11:31 AM, Jike Song wrote:
> On 10/27/2016 08:24 PM, Kirti Wankhede wrote:
>>
>>
>> On 10/27/2016 5:41 PM, Jike Song wrote:
>>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input
>>>> argument.
>>>>
>>>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>>>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>>>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52
>>>> ---
>>>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++-------
>>>> 1 file changed, 18 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
>>>> index 72fee415044a..3d916b965492 100644
>>>> --- a/drivers/vfio/vfio_iommu_type1.c
>>>> +++ b/drivers/vfio/vfio_iommu_type1.c
>>>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot)
>>>> return 0;
>>>> }
>>>>
>>>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
>>>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
>>>> + int prot, unsigned long *pfn)
>>>> {
>>>> struct page *page[1];
>>>> struct vm_area_struct *vma;
>>>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm);
>>>> int ret = -EFAULT;
>>>>
>>>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
>>>> + if (remote_mm) {
>>>> + down_read(&mm->mmap_sem);
>>>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1,
>>>> + !!(prot & IOMMU_WRITE), 0, page, NULL);
>>>
>>> Hi Kirti,
>>>
>>> It seems that get_user_pages_remote has only 7 args but you somehow gives 8
>>> here?
>>>
>>
>> I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c:
>>
>> long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
>> unsigned long start, unsigned long nr_pages,
>> int write, int force, struct page **pages,
>> struct vm_area_struct **vmas)
>> {
>> return __get_user_pages_locked(tsk, mm, start, nr_pages, write,
>> force,
>> pages, vmas, NULL, false,
>> FOLL_TOUCH | FOLL_REMOTE);
>> }
>> EXPORT_SYMBOL(get_user_pages_remote);
>
> It's queer. I checked:
>
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/mm/gup.c
>
> It still has 7 args.
>
> I believe you have seen this change somewhere, would you share the repo url
> and branch name of the linux-next you based on?
>
Sorry, my git was synced just few changes behind this change. I'll make
sure that I test the patch set at top of tree.
Thanks,
Kirti
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 01/19] vfio: Mediated device Core driver
2016-11-02 7:59 ` [Qemu-devel] " Kirti Wankhede
(?)
@ 2016-11-02 10:31 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 10:31 UTC (permalink / raw)
To: Kirti Wankhede
Cc: kevin.tian, cjia, kvm, qemu-devel, linux-kernel, alex.williamson,
kraxel, pbonzini, bjsdjshi
On 11/02/2016 03:59 PM, Kirti Wankhede wrote:
> On 10/29/2016 11:41 PM, Jike Song wrote:
>> On 10/29/2016 06:06 PM, Kirti Wankhede wrote:
>>>
>>>
>>> On 10/29/2016 10:00 AM, Jike Song wrote:
>>>> On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
>>>>> +int mdev_register_device(struct device *dev, const struct parent_ops *ops)
>>>>> +{
>>>>> + int ret;
>>>>> + struct parent_device *parent;
>>>>> +
>>>>> + /* check for mandatory ops */
>>>>> + if (!ops || !ops->create || !ops->remove || !ops->supported_type_groups)
>>>>> + return -EINVAL;
>>>>> +
>>>>> + dev = get_device(dev);
>>>>> + if (!dev)
>>>>> + return -EINVAL;
>>>>> +
>>>>> + mutex_lock(&parent_list_lock);
>>>>> +
>>>>> + /* Check for duplicate */
>>>>> + parent = __find_parent_device(dev);
>>>>> + if (parent) {
>>>>> + ret = -EEXIST;
>>>>> + goto add_dev_err;
>>>>> + }
>>>>> +
>>>>> + parent = kzalloc(sizeof(*parent), GFP_KERNEL);
>>>>> + if (!parent) {
>>>>> + ret = -ENOMEM;
>>>>> + goto add_dev_err;
>>>>> + }
>>>>> +
>>>>> + kref_init(&parent->ref);
>>>>> + mutex_init(&parent->lock);
>>>>> +
>>>>> + parent->dev = dev;
>>>>> + parent->ops = ops;
>>>>> +
>>>>> + ret = parent_create_sysfs_files(parent);
>>>>> + if (ret) {
>>>>> + mutex_unlock(&parent_list_lock);
>>>>> + mdev_put_parent(parent);
>>>>> + return ret;
>>>>> + }
>>>>> +
>>>>> + ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL);
>>>>> + if (ret)
>>>>> + dev_warn(dev, "Failed to create compatibility class link\n");
>>>>> +
>>>>
>>>> Hi Kirti,
>>>>
>>>> Like I replied to previous version:
>>>>
>>>> http://www.spinics.net/lists/kvm/msg139331.html
>>>>
>>>
>>> Hi Jike,
>>>
>>> I saw your reply but by that time v10 version of patch series was out
>>> for review.
>>>
>>
>> Ah..yes, I forgot that :)
>>
>>>> You can always check if mdev_bus_compat_class already registered
>>>> here, and register it if not yet. Same logic should be adopted to
>>>> mdev_init.
>>>>
>>>> Current implementation will simply panic if configured as builtin,
>>>> which is rare but far from impossible.
>>>>
>>>
>>> Can you verify attached patch with v10 patch-set whether this works for you?
>>> I'll incorporate this change in my next version.
>>>
>>
>> Seems cool. But would you please also keep the register in mdev_init(),
>> just check the 'in case it was already registered' case? Thanks!
>>
>
> The class is used only to keep symbolic to the devices which are
> registered to mdev framework. So I think its ok to register this class
> when first device is registered.
>
That's also cool :-)
So if you like it:
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 02/19] vfio: VFIO based driver for Mediated devices
2016-10-26 21:29 ` Kirti Wankhede
@ 2016-11-02 10:39 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 10:39 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> vfio_mdev driver registers with mdev core driver.
> mdev core driver creates mediated device and calls probe routine of
> vfio_mdev driver for each device.
> Probe routine of vfio_mdev driver adds mediated device to VFIO core module
>
> This driver forms a shim layer that pass through VFIO devices operations
> to vendor driver for mediated devices.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
> ---
> drivers/vfio/mdev/Kconfig | 7 ++
> drivers/vfio/mdev/Makefile | 1 +
> drivers/vfio/mdev/vfio_mdev.c | 148 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 156 insertions(+)
> create mode 100644 drivers/vfio/mdev/vfio_mdev.c
>
> diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
> index 303c14ce2847..1222bc6074e1 100644
> --- a/drivers/vfio/mdev/Kconfig
> +++ b/drivers/vfio/mdev/Kconfig
> @@ -8,3 +8,10 @@ config VFIO_MDEV
> See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
>
> If you don't know what do here, say N.
> +
> +config VFIO_MDEV_DEVICE
> + tristate "VFIO support for Mediated devices"
> + depends on VFIO && VFIO_MDEV
> + default n
> + help
> + VFIO based driver for mediated devices.
> diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
> index 31bc04801d94..fa2d5ea466ee 100644
> --- a/drivers/vfio/mdev/Makefile
> +++ b/drivers/vfio/mdev/Makefile
> @@ -2,3 +2,4 @@
> mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
>
> obj-$(CONFIG_VFIO_MDEV) += mdev.o
> +obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
> diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
> new file mode 100644
> index 000000000000..bb534d19e321
> --- /dev/null
> +++ b/drivers/vfio/mdev/vfio_mdev.c
> @@ -0,0 +1,148 @@
> +/*
> + * VFIO based driver for Mediated device
> + *
> + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
> + * Author: Neo Jia <cjia@nvidia.com>
> + * Kirti Wankhede <kwankhede@nvidia.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/vfio.h>
> +#include <linux/mdev.h>
> +
> +#include "mdev_private.h"
> +
> +#define DRIVER_VERSION "0.1"
> +#define DRIVER_AUTHOR "NVIDIA Corporation"
> +#define DRIVER_DESC "VFIO based driver for Mediated device"
> +
> +static int vfio_mdev_open(void *device_data)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> + int ret;
> +
> + if (unlikely(!parent->ops->open))
> + return -EINVAL;
> +
> + if (!try_module_get(THIS_MODULE))
> + return -ENODEV;
> +
> + ret = parent->ops->open(mdev);
> + if (ret)
> + module_put(THIS_MODULE);
> +
> + return ret;
> +}
> +
> +static void vfio_mdev_release(void *device_data)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (likely(parent->ops->release))
> + parent->ops->release(mdev);
> +
> + module_put(THIS_MODULE);
> +}
> +
> +static long vfio_mdev_unlocked_ioctl(void *device_data,
> + unsigned int cmd, unsigned long arg)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->ioctl))
> + return -EINVAL;
> +
> + return parent->ops->ioctl(mdev, cmd, arg);
> +}
> +
> +static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->read))
> + return -EINVAL;
> +
> + return parent->ops->read(mdev, buf, count, ppos);
> +}
> +
> +static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->write))
> + return -EINVAL;
> +
> + return parent->ops->write(mdev, buf, count, ppos);
> +}
> +
> +static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->mmap))
> + return -EINVAL;
> +
> + return parent->ops->mmap(mdev, vma);
> +}
> +
> +static const struct vfio_device_ops vfio_mdev_dev_ops = {
> + .name = "vfio-mdev",
> + .open = vfio_mdev_open,
> + .release = vfio_mdev_release,
> + .ioctl = vfio_mdev_unlocked_ioctl,
> + .read = vfio_mdev_read,
> + .write = vfio_mdev_write,
> + .mmap = vfio_mdev_mmap,
> +};
> +
> +int vfio_mdev_probe(struct device *dev)
> +{
> + struct mdev_device *mdev = to_mdev_device(dev);
> +
> + return vfio_add_group_dev(dev, &vfio_mdev_dev_ops, mdev);
> +}
> +
> +void vfio_mdev_remove(struct device *dev)
> +{
> + vfio_del_group_dev(dev);
> +}
> +
> +struct mdev_driver vfio_mdev_driver = {
> + .name = "vfio_mdev",
> + .probe = vfio_mdev_probe,
> + .remove = vfio_mdev_remove,
> +};
> +
> +static int __init vfio_mdev_init(void)
> +{
> + return mdev_register_driver(&vfio_mdev_driver, THIS_MODULE);
> +}
> +
> +static void __exit vfio_mdev_exit(void)
> +{
> + mdev_unregister_driver(&vfio_mdev_driver);
> +}
> +
> +module_init(vfio_mdev_init)
> +module_exit(vfio_mdev_exit)
> +
> +MODULE_VERSION(DRIVER_VERSION);
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR(DRIVER_AUTHOR);
> +MODULE_DESCRIPTION(DRIVER_DESC);
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 02/19] vfio: VFIO based driver for Mediated devices
@ 2016-11-02 10:39 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 10:39 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> vfio_mdev driver registers with mdev core driver.
> mdev core driver creates mediated device and calls probe routine of
> vfio_mdev driver for each device.
> Probe routine of vfio_mdev driver adds mediated device to VFIO core module
>
> This driver forms a shim layer that pass through VFIO devices operations
> to vendor driver for mediated devices.
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
> ---
> drivers/vfio/mdev/Kconfig | 7 ++
> drivers/vfio/mdev/Makefile | 1 +
> drivers/vfio/mdev/vfio_mdev.c | 148 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 156 insertions(+)
> create mode 100644 drivers/vfio/mdev/vfio_mdev.c
>
> diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
> index 303c14ce2847..1222bc6074e1 100644
> --- a/drivers/vfio/mdev/Kconfig
> +++ b/drivers/vfio/mdev/Kconfig
> @@ -8,3 +8,10 @@ config VFIO_MDEV
> See Documentation/vfio-mdev/vfio-mediated-device.txt for more details.
>
> If you don't know what do here, say N.
> +
> +config VFIO_MDEV_DEVICE
> + tristate "VFIO support for Mediated devices"
> + depends on VFIO && VFIO_MDEV
> + default n
> + help
> + VFIO based driver for mediated devices.
> diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
> index 31bc04801d94..fa2d5ea466ee 100644
> --- a/drivers/vfio/mdev/Makefile
> +++ b/drivers/vfio/mdev/Makefile
> @@ -2,3 +2,4 @@
> mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
>
> obj-$(CONFIG_VFIO_MDEV) += mdev.o
> +obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
> diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
> new file mode 100644
> index 000000000000..bb534d19e321
> --- /dev/null
> +++ b/drivers/vfio/mdev/vfio_mdev.c
> @@ -0,0 +1,148 @@
> +/*
> + * VFIO based driver for Mediated device
> + *
> + * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
> + * Author: Neo Jia <cjia@nvidia.com>
> + * Kirti Wankhede <kwankhede@nvidia.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/vfio.h>
> +#include <linux/mdev.h>
> +
> +#include "mdev_private.h"
> +
> +#define DRIVER_VERSION "0.1"
> +#define DRIVER_AUTHOR "NVIDIA Corporation"
> +#define DRIVER_DESC "VFIO based driver for Mediated device"
> +
> +static int vfio_mdev_open(void *device_data)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> + int ret;
> +
> + if (unlikely(!parent->ops->open))
> + return -EINVAL;
> +
> + if (!try_module_get(THIS_MODULE))
> + return -ENODEV;
> +
> + ret = parent->ops->open(mdev);
> + if (ret)
> + module_put(THIS_MODULE);
> +
> + return ret;
> +}
> +
> +static void vfio_mdev_release(void *device_data)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (likely(parent->ops->release))
> + parent->ops->release(mdev);
> +
> + module_put(THIS_MODULE);
> +}
> +
> +static long vfio_mdev_unlocked_ioctl(void *device_data,
> + unsigned int cmd, unsigned long arg)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->ioctl))
> + return -EINVAL;
> +
> + return parent->ops->ioctl(mdev, cmd, arg);
> +}
> +
> +static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->read))
> + return -EINVAL;
> +
> + return parent->ops->read(mdev, buf, count, ppos);
> +}
> +
> +static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->write))
> + return -EINVAL;
> +
> + return parent->ops->write(mdev, buf, count, ppos);
> +}
> +
> +static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
> +{
> + struct mdev_device *mdev = device_data;
> + struct parent_device *parent = mdev->parent;
> +
> + if (unlikely(!parent->ops->mmap))
> + return -EINVAL;
> +
> + return parent->ops->mmap(mdev, vma);
> +}
> +
> +static const struct vfio_device_ops vfio_mdev_dev_ops = {
> + .name = "vfio-mdev",
> + .open = vfio_mdev_open,
> + .release = vfio_mdev_release,
> + .ioctl = vfio_mdev_unlocked_ioctl,
> + .read = vfio_mdev_read,
> + .write = vfio_mdev_write,
> + .mmap = vfio_mdev_mmap,
> +};
> +
> +int vfio_mdev_probe(struct device *dev)
> +{
> + struct mdev_device *mdev = to_mdev_device(dev);
> +
> + return vfio_add_group_dev(dev, &vfio_mdev_dev_ops, mdev);
> +}
> +
> +void vfio_mdev_remove(struct device *dev)
> +{
> + vfio_del_group_dev(dev);
> +}
> +
> +struct mdev_driver vfio_mdev_driver = {
> + .name = "vfio_mdev",
> + .probe = vfio_mdev_probe,
> + .remove = vfio_mdev_remove,
> +};
> +
> +static int __init vfio_mdev_init(void)
> +{
> + return mdev_register_driver(&vfio_mdev_driver, THIS_MODULE);
> +}
> +
> +static void __exit vfio_mdev_exit(void)
> +{
> + mdev_unregister_driver(&vfio_mdev_driver);
> +}
> +
> +module_init(vfio_mdev_init)
> +module_exit(vfio_mdev_exit)
> +
> +MODULE_VERSION(DRIVER_VERSION);
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR(DRIVER_AUTHOR);
> +MODULE_DESCRIPTION(DRIVER_DESC);
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 03/19] vfio: Rearrange functions to get vfio_group from dev
2016-10-26 21:29 ` Kirti Wankhede
@ 2016-11-02 10:41 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 10:41 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> This patch rearranges functions to get vfio_group from device
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I1f93262bdbab75094bc24b087b29da35ba70c4c6
> ---
> drivers/vfio/vfio.c | 23 ++++++++++++++++-------
> 1 file changed, 16 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index d1d70e0b011b..23bc86c1d05d 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -480,6 +480,21 @@ static struct vfio_group *vfio_group_get_from_minor(int minor)
> return group;
> }
>
> +static struct vfio_group *vfio_group_get_from_dev(struct device *dev)
> +{
> + struct iommu_group *iommu_group;
> + struct vfio_group *group;
> +
> + iommu_group = iommu_group_get(dev);
> + if (!iommu_group)
> + return NULL;
> +
> + group = vfio_group_get_from_iommu(iommu_group);
> + iommu_group_put(iommu_group);
> +
> + return group;
> +}
> +
> /**
> * Device objects - create, release, get, put, search
> */
> @@ -811,16 +826,10 @@ EXPORT_SYMBOL_GPL(vfio_add_group_dev);
> */
> struct vfio_device *vfio_device_get_from_dev(struct device *dev)
> {
> - struct iommu_group *iommu_group;
> struct vfio_group *group;
> struct vfio_device *device;
>
> - iommu_group = iommu_group_get(dev);
> - if (!iommu_group)
> - return NULL;
> -
> - group = vfio_group_get_from_iommu(iommu_group);
> - iommu_group_put(iommu_group);
> + group = vfio_group_get_from_dev(dev);
> if (!group)
> return NULL;
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 03/19] vfio: Rearrange functions to get vfio_group from dev
@ 2016-11-02 10:41 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 10:41 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> This patch rearranges functions to get vfio_group from device
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I1f93262bdbab75094bc24b087b29da35ba70c4c6
> ---
> drivers/vfio/vfio.c | 23 ++++++++++++++++-------
> 1 file changed, 16 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index d1d70e0b011b..23bc86c1d05d 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -480,6 +480,21 @@ static struct vfio_group *vfio_group_get_from_minor(int minor)
> return group;
> }
>
> +static struct vfio_group *vfio_group_get_from_dev(struct device *dev)
> +{
> + struct iommu_group *iommu_group;
> + struct vfio_group *group;
> +
> + iommu_group = iommu_group_get(dev);
> + if (!iommu_group)
> + return NULL;
> +
> + group = vfio_group_get_from_iommu(iommu_group);
> + iommu_group_put(iommu_group);
> +
> + return group;
> +}
> +
> /**
> * Device objects - create, release, get, put, search
> */
> @@ -811,16 +826,10 @@ EXPORT_SYMBOL_GPL(vfio_add_group_dev);
> */
> struct vfio_device *vfio_device_get_from_dev(struct device *dev)
> {
> - struct iommu_group *iommu_group;
> struct vfio_group *group;
> struct vfio_device *device;
>
> - iommu_group = iommu_group_get(dev);
> - if (!iommu_group)
> - return NULL;
> -
> - group = vfio_group_get_from_iommu(iommu_group);
> - iommu_group_put(iommu_group);
> + group = vfio_group_get_from_dev(dev);
> if (!group)
> return NULL;
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 04/19] vfio: Common function to increment container_users
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-11-02 11:34 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 11:34 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> This change rearrange functions to have common function to increment
> container_users
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I8bdeb352bc8439b107ffd519480fd4dc238677f2
> ---
> drivers/vfio/vfio.c | 34 +++++++++++++++++++++-------------
> 1 file changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 23bc86c1d05d..2e83bdf007fe 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1385,6 +1385,23 @@ static bool vfio_group_viable(struct vfio_group *group)
> group, vfio_dev_viable) == 0);
> }
>
> +static int vfio_group_add_container_user(struct vfio_group *group)
> +{
> + if (!atomic_inc_not_zero(&group->container_users))
> + return -EINVAL;
> +
> + if (group->noiommu) {
> + atomic_dec(&group->container_users);
> + return -EPERM;
> + }
trivial: a blank line here
> + if (!group->container->iommu_driver || !vfio_group_viable(group)) {
> + atomic_dec(&group->container_users);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> static const struct file_operations vfio_device_fops;
>
> static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
> @@ -1694,23 +1711,14 @@ static const struct file_operations vfio_device_fops = {
> struct vfio_group *vfio_group_get_external_user(struct file *filep)
> {
> struct vfio_group *group = filep->private_data;
> + int ret;
>
> if (filep->f_op != &vfio_group_fops)
> return ERR_PTR(-EINVAL);
>
> - if (!atomic_inc_not_zero(&group->container_users))
> - return ERR_PTR(-EINVAL);
> -
> - if (group->noiommu) {
> - atomic_dec(&group->container_users);
> - return ERR_PTR(-EPERM);
> - }
> -
> - if (!group->container->iommu_driver ||
> - !vfio_group_viable(group)) {
> - atomic_dec(&group->container_users);
> - return ERR_PTR(-EINVAL);
> - }
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + return ERR_PTR(ret);
>
> vfio_group_get(group);
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 04/19] vfio: Common function to increment container_users
@ 2016-11-02 11:34 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 11:34 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> This change rearrange functions to have common function to increment
> container_users
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I8bdeb352bc8439b107ffd519480fd4dc238677f2
> ---
> drivers/vfio/vfio.c | 34 +++++++++++++++++++++-------------
> 1 file changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 23bc86c1d05d..2e83bdf007fe 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -1385,6 +1385,23 @@ static bool vfio_group_viable(struct vfio_group *group)
> group, vfio_dev_viable) == 0);
> }
>
> +static int vfio_group_add_container_user(struct vfio_group *group)
> +{
> + if (!atomic_inc_not_zero(&group->container_users))
> + return -EINVAL;
> +
> + if (group->noiommu) {
> + atomic_dec(&group->container_users);
> + return -EPERM;
> + }
trivial: a blank line here
> + if (!group->container->iommu_driver || !vfio_group_viable(group)) {
> + atomic_dec(&group->container_users);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> static const struct file_operations vfio_device_fops;
>
> static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
> @@ -1694,23 +1711,14 @@ static const struct file_operations vfio_device_fops = {
> struct vfio_group *vfio_group_get_external_user(struct file *filep)
> {
> struct vfio_group *group = filep->private_data;
> + int ret;
>
> if (filep->f_op != &vfio_group_fops)
> return ERR_PTR(-EINVAL);
>
> - if (!atomic_inc_not_zero(&group->container_users))
> - return ERR_PTR(-EINVAL);
> -
> - if (group->noiommu) {
> - atomic_dec(&group->container_users);
> - return ERR_PTR(-EPERM);
> - }
> -
> - if (!group->container->iommu_driver ||
> - !vfio_group_viable(group)) {
> - atomic_dec(&group->container_users);
> - return ERR_PTR(-EINVAL);
> - }
> + ret = vfio_group_add_container_user(group);
> + if (ret)
> + return ERR_PTR(ret);
>
> vfio_group_get(group);
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 09/19] vfio iommu type1: Add support for mediated devices
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-11-02 13:29 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 13:29 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> VFIO IOMMU drivers are designed for the devices which are IOMMU capable.
> Mediated device only uses IOMMU APIs, the underlying hardware can be
> managed by an IOMMU domain.
>
> Aim of this change is:
> - To use most of the code of TYPE1 IOMMU driver for mediated devices
> - To support direct assigned device and mediated device in single module
>
> This change adds pin and unpin support for mediated device to TYPE1 IOMMU
> backend module. More details:
> - When iommu_group of mediated devices is attached, task structure is
> cached which is used later to pin pages and page accounting.
> - It keeps track of pinned pages for mediated domain. This data is used to
> verify unpinning request and to unpin remaining pages while detaching, if
> there are any.
> - Used existing mechanism for page accounting. If iommu capable domain
> exist in the container then all pages are already pinned and accounted.
> Accouting for mdev device is only done if there is no iommu capable
> domain in the container.
> - Page accouting is updated on hot plug and unplug mdev device and pass
> through device.
>
> Tested by assigning below combinations of devices to a single VM:
> - GPU pass through only
> - vGPU device only
> - One GPU pass through and one vGPU device
> - Linux VM hot plug and unplug vGPU device while GPU pass through device
> exist
> - Linux VM hot plug and unplug GPU pass through device while vGPU device
> exist
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I295d6f0f2e0579b8d9882bfd8fd5a4194b97bd9a
> ---
> drivers/vfio/vfio_iommu_type1.c | 646 +++++++++++++++++++++++++++++++++++-----
> 1 file changed, 571 insertions(+), 75 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 861ac2a1b0c3..5add11a147e1 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -36,6 +36,7 @@
> #include <linux/uaccess.h>
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> +#include <linux/mdev.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -55,18 +56,26 @@ MODULE_PARM_DESC(disable_hugepages,
>
> struct vfio_iommu {
> struct list_head domain_list;
> + struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> bool v2;
> bool nesting;
> };
>
> +struct external_addr_space {
> + struct task_struct *task;
> + struct rb_root pfn_list; /* pinned Host pfn list */
> + struct mutex pfn_list_lock; /* mutex for pfn_list */
> +};
> +
> struct vfio_domain {
> - struct iommu_domain *domain;
> - struct list_head next;
> - struct list_head group_list;
> - int prot; /* IOMMU_CACHE */
> - bool fgsp; /* Fine-grained super pages */
> + struct iommu_domain *domain;
> + struct list_head next;
> + struct list_head group_list;
> + struct external_addr_space *external_addr_space;
> + int prot; /* IOMMU_CACHE */
> + bool fgsp; /* Fine-grained super pages */
> };
>
> struct vfio_dma {
> @@ -75,6 +84,7 @@ struct vfio_dma {
> unsigned long vaddr; /* Process virtual addr */
> size_t size; /* Map size (bytes) */
> int prot; /* IOMMU_READ/WRITE */
> + bool iommu_mapped;
> };
>
> struct vfio_group {
> @@ -83,6 +93,21 @@ struct vfio_group {
> };
>
> /*
> + * Guest RAM pinning working set or DMA target
> + */
> +struct vfio_pfn {
> + struct rb_node node;
> + unsigned long vaddr; /* virtual addr */
> + dma_addr_t iova; /* IOVA */
> + unsigned long pfn; /* Host pfn */
> + int prot;
> + atomic_t ref_count;
> +};
> +
> +#define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \
> + (!list_empty(&iommu->domain_list))
> +
> +/*
> * This code handles mapping and unmapping of user data buffers
> * into DMA'ble space using the IOMMU
> */
> @@ -130,6 +155,101 @@ static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
> rb_erase(&old->node, &iommu->dma_list);
> }
>
> +/*
> + * Helper Functions for host pfn list
> + */
> +
> +static struct vfio_pfn *vfio_find_pfn(struct vfio_domain *domain,
> + unsigned long pfn)
> +{
> + struct rb_node *node;
> + struct vfio_pfn *vpfn;
> +
> + node = domain->external_addr_space->pfn_list.rb_node;
> +
> + while (node) {
> + vpfn = rb_entry(node, struct vfio_pfn, node);
> +
> + if (pfn < vpfn->pfn)
> + node = node->rb_left;
> + else if (pfn > vpfn->pfn)
> + node = node->rb_right;
> + else
> + return vpfn;
> + }
> +
> + return NULL;
> +}
> +
> +static void vfio_link_pfn(struct vfio_domain *domain, struct vfio_pfn *new)
> +{
> + struct rb_node **link, *parent = NULL;
> + struct vfio_pfn *vpfn;
> +
> + link = &domain->external_addr_space->pfn_list.rb_node;
> + while (*link) {
> + parent = *link;
> + vpfn = rb_entry(parent, struct vfio_pfn, node);
> +
> + if (new->pfn < vpfn->pfn)
> + link = &(*link)->rb_left;
> + else
> + link = &(*link)->rb_right;
> + }
> +
> + rb_link_node(&new->node, parent, link);
> + rb_insert_color(&new->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static void vfio_unlink_pfn(struct vfio_domain *domain, struct vfio_pfn *old)
> +{
> + rb_erase(&old->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static int vfio_add_to_pfn_list(struct vfio_domain *domain, unsigned long vaddr,
> + dma_addr_t iova, unsigned long pfn, int prot)
> +{
> + struct vfio_pfn *vpfn;
> +
> + vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
> + if (!vpfn)
> + return -ENOMEM;
> +
> + vpfn->vaddr = vaddr;
> + vpfn->iova = iova;
> + vpfn->pfn = pfn;
> + vpfn->prot = prot;
> + atomic_set(&vpfn->ref_count, 1);
> + vfio_link_pfn(domain, vpfn);
> + return 0;
> +}
> +
> +static void vfio_remove_from_pfn_list(struct vfio_domain *domain,
> + struct vfio_pfn *vpfn)
> +{
> + vfio_unlink_pfn(domain, vpfn);
> + kfree(vpfn);
> +}
> +
> +static int vfio_pfn_account(struct vfio_iommu *iommu, unsigned long pfn)
> +{
> + struct vfio_pfn *p;
> + struct vfio_domain *domain = iommu->external_domain;
> + int ret = 1;
> +
> + if (!domain)
> + return 1;
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + p = vfio_find_pfn(domain, pfn);
> + if (p)
> + ret = 0;
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> + return ret;
> +}
> +
> struct vwork {
> struct mm_struct *mm;
> long npage;
> @@ -270,12 +390,13 @@ static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
> * the iommu can only map chunks of consecutive pfns anyway, so get the
> * first page and all consecutive pages with the same locking.
> */
> -static long vfio_pin_pages(unsigned long vaddr, long npage,
> - int prot, unsigned long *pfn_base)
> +static long __vfio_pin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long vaddr, long npage,
> + int prot, unsigned long *pfn_base)
> {
> unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> bool lock_cap = capable(CAP_IPC_LOCK);
> - long ret, i;
> + long ret, i, lock_acct = 0;
> bool rsvd;
>
> if (!current->mm)
> @@ -285,9 +406,11 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> if (ret)
> return ret;
>
> + lock_acct = vfio_pfn_account(iommu, *pfn_base);
> +
> rsvd = is_invalid_reserved_pfn(*pfn_base);
>
> - if (!rsvd && !lock_cap && current->mm->locked_vm + 1 > limit) {
> + if (!rsvd && !lock_cap && current->mm->locked_vm + lock_acct > limit) {
> put_pfn(*pfn_base, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
> limit << PAGE_SHIFT);
> @@ -314,8 +437,10 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> break;
> }
>
> + lock_acct += vfio_pfn_account(iommu, pfn);
> +
> if (!rsvd && !lock_cap &&
> - current->mm->locked_vm + i + 1 > limit) {
> + current->mm->locked_vm + lock_acct > limit) {
> put_pfn(pfn, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
> __func__, limit << PAGE_SHIFT);
> @@ -329,14 +454,19 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> return i;
> }
>
> -static long vfio_unpin_pages(unsigned long pfn, long npage,
> - int prot, bool do_accounting)
> +static long __vfio_unpin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long pfn, long npage, int prot,
> + bool do_accounting)
> {
> - unsigned long unlocked = 0;
> + unsigned long unlocked = 0, unlock_acct = 0;
> long i;
>
> - for (i = 0; i < npage; i++)
> + for (i = 0; i < npage; i++) {
> + if (do_accounting)
> + unlock_acct += vfio_pfn_account(iommu, pfn);
> +
> unlocked += put_pfn(pfn++, prot);
> + }
>
> if (do_accounting)
> vfio_lock_acct(current, -unlocked);
> @@ -344,14 +474,208 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
> return unlocked;
> }
>
> -static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
> +static long __vfio_pin_page_external(struct vfio_domain *domain,
> + unsigned long vaddr, int prot,
> + unsigned long *pfn_base,
> + bool do_accounting)
> +{
> + unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> + bool lock_cap = capable(CAP_IPC_LOCK);
> + long ret;
> + bool rsvd;
> + struct task_struct *task = domain->external_addr_space->task;
> +
> + if (!task->mm)
> + return -ENODEV;
> +
> + ret = vaddr_get_pfn(task->mm, vaddr, prot, pfn_base);
Hi Kirti,
In your implementation of vaddr_get_pfn, as long as the 1st argument
is not NULL, you will call get_user_pages_remote other than get_user_pages_fast.
But still there is a possibility here @task is actually @current, thereby
task->mm == current->mm. That should not be rare, but probably happen
at most times: the QEMU process emulates MMIO read/write, and call
vfio_pin_pages in its process context.
If I read correctly, current implementation enforces a locked GUP, no
matter which process context it is in.
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 09/19] vfio iommu type1: Add support for mediated devices
@ 2016-11-02 13:29 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 13:29 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> VFIO IOMMU drivers are designed for the devices which are IOMMU capable.
> Mediated device only uses IOMMU APIs, the underlying hardware can be
> managed by an IOMMU domain.
>
> Aim of this change is:
> - To use most of the code of TYPE1 IOMMU driver for mediated devices
> - To support direct assigned device and mediated device in single module
>
> This change adds pin and unpin support for mediated device to TYPE1 IOMMU
> backend module. More details:
> - When iommu_group of mediated devices is attached, task structure is
> cached which is used later to pin pages and page accounting.
> - It keeps track of pinned pages for mediated domain. This data is used to
> verify unpinning request and to unpin remaining pages while detaching, if
> there are any.
> - Used existing mechanism for page accounting. If iommu capable domain
> exist in the container then all pages are already pinned and accounted.
> Accouting for mdev device is only done if there is no iommu capable
> domain in the container.
> - Page accouting is updated on hot plug and unplug mdev device and pass
> through device.
>
> Tested by assigning below combinations of devices to a single VM:
> - GPU pass through only
> - vGPU device only
> - One GPU pass through and one vGPU device
> - Linux VM hot plug and unplug vGPU device while GPU pass through device
> exist
> - Linux VM hot plug and unplug GPU pass through device while vGPU device
> exist
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I295d6f0f2e0579b8d9882bfd8fd5a4194b97bd9a
> ---
> drivers/vfio/vfio_iommu_type1.c | 646 +++++++++++++++++++++++++++++++++++-----
> 1 file changed, 571 insertions(+), 75 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 861ac2a1b0c3..5add11a147e1 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -36,6 +36,7 @@
> #include <linux/uaccess.h>
> #include <linux/vfio.h>
> #include <linux/workqueue.h>
> +#include <linux/mdev.h>
>
> #define DRIVER_VERSION "0.2"
> #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
> @@ -55,18 +56,26 @@ MODULE_PARM_DESC(disable_hugepages,
>
> struct vfio_iommu {
> struct list_head domain_list;
> + struct vfio_domain *external_domain; /* domain for external user */
> struct mutex lock;
> struct rb_root dma_list;
> bool v2;
> bool nesting;
> };
>
> +struct external_addr_space {
> + struct task_struct *task;
> + struct rb_root pfn_list; /* pinned Host pfn list */
> + struct mutex pfn_list_lock; /* mutex for pfn_list */
> +};
> +
> struct vfio_domain {
> - struct iommu_domain *domain;
> - struct list_head next;
> - struct list_head group_list;
> - int prot; /* IOMMU_CACHE */
> - bool fgsp; /* Fine-grained super pages */
> + struct iommu_domain *domain;
> + struct list_head next;
> + struct list_head group_list;
> + struct external_addr_space *external_addr_space;
> + int prot; /* IOMMU_CACHE */
> + bool fgsp; /* Fine-grained super pages */
> };
>
> struct vfio_dma {
> @@ -75,6 +84,7 @@ struct vfio_dma {
> unsigned long vaddr; /* Process virtual addr */
> size_t size; /* Map size (bytes) */
> int prot; /* IOMMU_READ/WRITE */
> + bool iommu_mapped;
> };
>
> struct vfio_group {
> @@ -83,6 +93,21 @@ struct vfio_group {
> };
>
> /*
> + * Guest RAM pinning working set or DMA target
> + */
> +struct vfio_pfn {
> + struct rb_node node;
> + unsigned long vaddr; /* virtual addr */
> + dma_addr_t iova; /* IOVA */
> + unsigned long pfn; /* Host pfn */
> + int prot;
> + atomic_t ref_count;
> +};
> +
> +#define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \
> + (!list_empty(&iommu->domain_list))
> +
> +/*
> * This code handles mapping and unmapping of user data buffers
> * into DMA'ble space using the IOMMU
> */
> @@ -130,6 +155,101 @@ static void vfio_unlink_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
> rb_erase(&old->node, &iommu->dma_list);
> }
>
> +/*
> + * Helper Functions for host pfn list
> + */
> +
> +static struct vfio_pfn *vfio_find_pfn(struct vfio_domain *domain,
> + unsigned long pfn)
> +{
> + struct rb_node *node;
> + struct vfio_pfn *vpfn;
> +
> + node = domain->external_addr_space->pfn_list.rb_node;
> +
> + while (node) {
> + vpfn = rb_entry(node, struct vfio_pfn, node);
> +
> + if (pfn < vpfn->pfn)
> + node = node->rb_left;
> + else if (pfn > vpfn->pfn)
> + node = node->rb_right;
> + else
> + return vpfn;
> + }
> +
> + return NULL;
> +}
> +
> +static void vfio_link_pfn(struct vfio_domain *domain, struct vfio_pfn *new)
> +{
> + struct rb_node **link, *parent = NULL;
> + struct vfio_pfn *vpfn;
> +
> + link = &domain->external_addr_space->pfn_list.rb_node;
> + while (*link) {
> + parent = *link;
> + vpfn = rb_entry(parent, struct vfio_pfn, node);
> +
> + if (new->pfn < vpfn->pfn)
> + link = &(*link)->rb_left;
> + else
> + link = &(*link)->rb_right;
> + }
> +
> + rb_link_node(&new->node, parent, link);
> + rb_insert_color(&new->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static void vfio_unlink_pfn(struct vfio_domain *domain, struct vfio_pfn *old)
> +{
> + rb_erase(&old->node, &domain->external_addr_space->pfn_list);
> +}
> +
> +static int vfio_add_to_pfn_list(struct vfio_domain *domain, unsigned long vaddr,
> + dma_addr_t iova, unsigned long pfn, int prot)
> +{
> + struct vfio_pfn *vpfn;
> +
> + vpfn = kzalloc(sizeof(*vpfn), GFP_KERNEL);
> + if (!vpfn)
> + return -ENOMEM;
> +
> + vpfn->vaddr = vaddr;
> + vpfn->iova = iova;
> + vpfn->pfn = pfn;
> + vpfn->prot = prot;
> + atomic_set(&vpfn->ref_count, 1);
> + vfio_link_pfn(domain, vpfn);
> + return 0;
> +}
> +
> +static void vfio_remove_from_pfn_list(struct vfio_domain *domain,
> + struct vfio_pfn *vpfn)
> +{
> + vfio_unlink_pfn(domain, vpfn);
> + kfree(vpfn);
> +}
> +
> +static int vfio_pfn_account(struct vfio_iommu *iommu, unsigned long pfn)
> +{
> + struct vfio_pfn *p;
> + struct vfio_domain *domain = iommu->external_domain;
> + int ret = 1;
> +
> + if (!domain)
> + return 1;
> +
> + mutex_lock(&domain->external_addr_space->pfn_list_lock);
> +
> + p = vfio_find_pfn(domain, pfn);
> + if (p)
> + ret = 0;
> +
> + mutex_unlock(&domain->external_addr_space->pfn_list_lock);
> + return ret;
> +}
> +
> struct vwork {
> struct mm_struct *mm;
> long npage;
> @@ -270,12 +390,13 @@ static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr,
> * the iommu can only map chunks of consecutive pfns anyway, so get the
> * first page and all consecutive pages with the same locking.
> */
> -static long vfio_pin_pages(unsigned long vaddr, long npage,
> - int prot, unsigned long *pfn_base)
> +static long __vfio_pin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long vaddr, long npage,
> + int prot, unsigned long *pfn_base)
> {
> unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> bool lock_cap = capable(CAP_IPC_LOCK);
> - long ret, i;
> + long ret, i, lock_acct = 0;
> bool rsvd;
>
> if (!current->mm)
> @@ -285,9 +406,11 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> if (ret)
> return ret;
>
> + lock_acct = vfio_pfn_account(iommu, *pfn_base);
> +
> rsvd = is_invalid_reserved_pfn(*pfn_base);
>
> - if (!rsvd && !lock_cap && current->mm->locked_vm + 1 > limit) {
> + if (!rsvd && !lock_cap && current->mm->locked_vm + lock_acct > limit) {
> put_pfn(*pfn_base, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
> limit << PAGE_SHIFT);
> @@ -314,8 +437,10 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> break;
> }
>
> + lock_acct += vfio_pfn_account(iommu, pfn);
> +
> if (!rsvd && !lock_cap &&
> - current->mm->locked_vm + i + 1 > limit) {
> + current->mm->locked_vm + lock_acct > limit) {
> put_pfn(pfn, prot);
> pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
> __func__, limit << PAGE_SHIFT);
> @@ -329,14 +454,19 @@ static long vfio_pin_pages(unsigned long vaddr, long npage,
> return i;
> }
>
> -static long vfio_unpin_pages(unsigned long pfn, long npage,
> - int prot, bool do_accounting)
> +static long __vfio_unpin_pages_remote(struct vfio_iommu *iommu,
> + unsigned long pfn, long npage, int prot,
> + bool do_accounting)
> {
> - unsigned long unlocked = 0;
> + unsigned long unlocked = 0, unlock_acct = 0;
> long i;
>
> - for (i = 0; i < npage; i++)
> + for (i = 0; i < npage; i++) {
> + if (do_accounting)
> + unlock_acct += vfio_pfn_account(iommu, pfn);
> +
> unlocked += put_pfn(pfn++, prot);
> + }
>
> if (do_accounting)
> vfio_lock_acct(current, -unlocked);
> @@ -344,14 +474,208 @@ static long vfio_unpin_pages(unsigned long pfn, long npage,
> return unlocked;
> }
>
> -static void vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma)
> +static long __vfio_pin_page_external(struct vfio_domain *domain,
> + unsigned long vaddr, int prot,
> + unsigned long *pfn_base,
> + bool do_accounting)
> +{
> + unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
> + bool lock_cap = capable(CAP_IPC_LOCK);
> + long ret;
> + bool rsvd;
> + struct task_struct *task = domain->external_addr_space->task;
> +
> + if (!task->mm)
> + return -ENODEV;
> +
> + ret = vaddr_get_pfn(task->mm, vaddr, prot, pfn_base);
Hi Kirti,
In your implementation of vaddr_get_pfn, as long as the 1st argument
is not NULL, you will call get_user_pages_remote other than get_user_pages_fast.
But still there is a possibility here @task is actually @current, thereby
task->mm == current->mm. That should not be rare, but probably happen
at most times: the QEMU process emulates MMIO read/write, and call
vfio_pin_pages in its process context.
If I read correctly, current implementation enforces a locked GUP, no
matter which process context it is in.
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [PATCH v10 08/19] vfio iommu type1: Add find_iommu_group() function
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
@ 2016-11-02 14:13 ` Jike Song
-1 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 14:13 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Add find_iommu_group()
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I9d372f1ebe9eb01a5a21374b8a2b03f7df73601f
> ---
> drivers/vfio/vfio_iommu_type1.c | 58 ++++++++++++++++++++++++-----------------
> 1 file changed, 34 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 3d916b965492..861ac2a1b0c3 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -745,11 +745,24 @@ static void vfio_test_domain_fgsp(struct vfio_domain *domain)
> __free_pages(pages, order);
> }
>
> +static struct vfio_group *find_iommu_group(struct vfio_domain *domain,
> + struct iommu_group *iommu_group)
> +{
> + struct vfio_group *g;
> +
> + list_for_each_entry(g, &domain->group_list, next) {
> + if (g->iommu_group == iommu_group)
> + return g;
> + }
> +
> + return NULL;
> +}
> +
> static int vfio_iommu_type1_attach_group(void *iommu_data,
> struct iommu_group *iommu_group)
> {
> struct vfio_iommu *iommu = iommu_data;
> - struct vfio_group *group, *g;
> + struct vfio_group *group;
> struct vfio_domain *domain, *d;
> struct bus_type *bus = NULL;
> int ret;
> @@ -757,10 +770,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> mutex_lock(&iommu->lock);
>
> list_for_each_entry(d, &iommu->domain_list, next) {
> - list_for_each_entry(g, &d->group_list, next) {
> - if (g->iommu_group != iommu_group)
> - continue;
> -
> + if (find_iommu_group(d, iommu_group)) {
> mutex_unlock(&iommu->lock);
> return -EINVAL;
> }
> @@ -879,28 +889,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> +
> list_for_each_entry(domain, &iommu->domain_list, next) {
> - list_for_each_entry(group, &domain->group_list, next) {
> - if (group->iommu_group != iommu_group)
> - continue;
> + group = find_iommu_group(domain, iommu_group);
> + if (!group)
> + continue;
>
> - iommu_detach_group(domain->domain, iommu_group);
> - list_del(&group->next);
> - kfree(group);
> - /*
> - * Group ownership provides privilege, if the group
> - * list is empty, the domain goes away. If it's the
> - * last domain, then all the mappings go away too.
> - */
> - if (list_empty(&domain->group_list)) {
> - if (list_is_singular(&iommu->domain_list))
> - vfio_iommu_unmap_unpin_all(iommu);
> - iommu_domain_free(domain->domain);
> - list_del(&domain->next);
> - kfree(domain);
> - }
> - goto done;
> + iommu_detach_group(domain->domain, iommu_group);
> + list_del(&group->next);
> + kfree(group);
> + /*
> + * Group ownership provides privilege, if the group
> + * list is empty, the domain goes away. If it's the
> + * last domain, then all the mappings go away too.
> + */
> + if (list_empty(&domain->group_list)) {
> + if (list_is_singular(&iommu->domain_list))
> + vfio_iommu_unmap_unpin_all(iommu);
> + iommu_domain_free(domain->domain);
> + list_del(&domain->next);
> + kfree(domain);
> }
> + goto done;
> }
>
> done:
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
* Re: [Qemu-devel] [PATCH v10 08/19] vfio iommu type1: Add find_iommu_group() function
@ 2016-11-02 14:13 ` Jike Song
0 siblings, 0 replies; 119+ messages in thread
From: Jike Song @ 2016-11-02 14:13 UTC (permalink / raw)
To: Kirti Wankhede
Cc: alex.williamson, pbonzini, kraxel, cjia, qemu-devel, kvm,
kevin.tian, bjsdjshi, linux-kernel
On 10/27/2016 05:29 AM, Kirti Wankhede wrote:
> Add find_iommu_group()
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Signed-off-by: Neo Jia <cjia@nvidia.com>
> Change-Id: I9d372f1ebe9eb01a5a21374b8a2b03f7df73601f
> ---
> drivers/vfio/vfio_iommu_type1.c | 58 ++++++++++++++++++++++++-----------------
> 1 file changed, 34 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 3d916b965492..861ac2a1b0c3 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -745,11 +745,24 @@ static void vfio_test_domain_fgsp(struct vfio_domain *domain)
> __free_pages(pages, order);
> }
>
> +static struct vfio_group *find_iommu_group(struct vfio_domain *domain,
> + struct iommu_group *iommu_group)
> +{
> + struct vfio_group *g;
> +
> + list_for_each_entry(g, &domain->group_list, next) {
> + if (g->iommu_group == iommu_group)
> + return g;
> + }
> +
> + return NULL;
> +}
> +
> static int vfio_iommu_type1_attach_group(void *iommu_data,
> struct iommu_group *iommu_group)
> {
> struct vfio_iommu *iommu = iommu_data;
> - struct vfio_group *group, *g;
> + struct vfio_group *group;
> struct vfio_domain *domain, *d;
> struct bus_type *bus = NULL;
> int ret;
> @@ -757,10 +770,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> mutex_lock(&iommu->lock);
>
> list_for_each_entry(d, &iommu->domain_list, next) {
> - list_for_each_entry(g, &d->group_list, next) {
> - if (g->iommu_group != iommu_group)
> - continue;
> -
> + if (find_iommu_group(d, iommu_group)) {
> mutex_unlock(&iommu->lock);
> return -EINVAL;
> }
> @@ -879,28 +889,28 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
>
> mutex_lock(&iommu->lock);
>
> +
> list_for_each_entry(domain, &iommu->domain_list, next) {
> - list_for_each_entry(group, &domain->group_list, next) {
> - if (group->iommu_group != iommu_group)
> - continue;
> + group = find_iommu_group(domain, iommu_group);
> + if (!group)
> + continue;
>
> - iommu_detach_group(domain->domain, iommu_group);
> - list_del(&group->next);
> - kfree(group);
> - /*
> - * Group ownership provides privilege, if the group
> - * list is empty, the domain goes away. If it's the
> - * last domain, then all the mappings go away too.
> - */
> - if (list_empty(&domain->group_list)) {
> - if (list_is_singular(&iommu->domain_list))
> - vfio_iommu_unmap_unpin_all(iommu);
> - iommu_domain_free(domain->domain);
> - list_del(&domain->next);
> - kfree(domain);
> - }
> - goto done;
> + iommu_detach_group(domain->domain, iommu_group);
> + list_del(&group->next);
> + kfree(group);
> + /*
> + * Group ownership provides privilege, if the group
> + * list is empty, the domain goes away. If it's the
> + * last domain, then all the mappings go away too.
> + */
> + if (list_empty(&domain->group_list)) {
> + if (list_is_singular(&iommu->domain_list))
> + vfio_iommu_unmap_unpin_all(iommu);
> + iommu_domain_free(domain->domain);
> + list_del(&domain->next);
> + kfree(domain);
> }
> + goto done;
> }
>
> done:
>
Reviewed-by: Jike Song <jike.song@intel.com>
--
Thanks,
Jike
^ permalink raw reply [flat|nested] 119+ messages in thread
end of thread, other threads:[~2016-11-02 14:17 UTC | newest]
Thread overview: 119+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-10-26 21:29 [PATCH v10 00/19] Add Mediated device support Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 01/19] vfio: Mediated device Core driver Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-29 4:30 ` Jike Song
2016-10-29 4:30 ` [Qemu-devel] " Jike Song
2016-10-29 10:06 ` Kirti Wankhede
2016-10-29 10:06 ` [Qemu-devel] " Kirti Wankhede
2016-10-29 18:11 ` Jike Song
2016-10-29 18:11 ` [Qemu-devel] " Jike Song
2016-11-02 7:59 ` Kirti Wankhede
2016-11-02 7:59 ` [Qemu-devel] " Kirti Wankhede
2016-11-02 10:31 ` Jike Song
2016-11-01 3:08 ` Jike Song
2016-11-01 3:08 ` [Qemu-devel] " Jike Song
2016-11-01 3:44 ` Alex Williamson
2016-11-01 3:44 ` [Qemu-devel] " Alex Williamson
2016-11-01 5:28 ` Jike Song
2016-11-01 5:28 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 02/19] vfio: VFIO based driver for Mediated devices Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` Kirti Wankhede
2016-11-02 10:39 ` Jike Song
2016-11-02 10:39 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 03/19] vfio: Rearrange functions to get vfio_group from dev Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` Kirti Wankhede
2016-11-02 10:41 ` Jike Song
2016-11-02 10:41 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 04/19] vfio: Common function to increment container_users Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-11-02 11:34 ` Jike Song
2016-11-02 11:34 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 05/19] vfio iommu: Added pin and unpin callback functions to vfio_iommu_driver_ops Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-11-01 8:07 ` Jike Song
2016-11-01 8:07 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 06/19] vfio iommu type1: Update arguments of vfio_lock_acct Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn() Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-27 12:11 ` Jike Song
2016-10-27 12:11 ` [Qemu-devel] " Jike Song
2016-10-27 12:11 ` Jike Song
2016-10-27 12:24 ` Kirti Wankhede
2016-10-27 12:24 ` [Qemu-devel] " Kirti Wankhede
2016-10-27 12:24 ` Kirti Wankhede
2016-10-28 6:01 ` Jike Song
2016-10-28 6:01 ` [Qemu-devel] " Jike Song
2016-11-02 8:06 ` Kirti Wankhede
2016-11-02 8:06 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 08/19] vfio iommu type1: Add find_iommu_group() function Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-11-02 14:13 ` Jike Song
2016-11-02 14:13 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 09/19] vfio iommu type1: Add support for mediated devices Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-27 23:01 ` Alex Williamson
2016-10-27 23:01 ` [Qemu-devel] " Alex Williamson
2016-11-02 13:29 ` Jike Song
2016-11-02 13:29 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 10/19] vfio iommu: Add blocking notifier to notify DMA_UNMAP Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-28 7:33 ` Jike Song
2016-10-28 7:33 ` [Qemu-devel] " Jike Song
2016-10-28 12:38 ` Kirti Wankhede
2016-10-28 12:38 ` [Qemu-devel] " Kirti Wankhede
2016-10-28 12:40 ` Alex Williamson
2016-10-28 12:40 ` [Qemu-devel] " Alex Williamson
2016-10-28 20:02 ` Kirti Wankhede
2016-10-28 20:02 ` [Qemu-devel] " Kirti Wankhede
2016-10-28 20:33 ` Alex Williamson
2016-10-28 20:33 ` [Qemu-devel] " Alex Williamson
2016-10-29 10:37 ` Kirti Wankhede
2016-10-29 10:37 ` [Qemu-devel] " Kirti Wankhede
2016-10-29 14:03 ` Alex Williamson
2016-10-29 14:03 ` [Qemu-devel] " Alex Williamson
2016-10-29 14:03 ` Alex Williamson
2016-11-01 3:45 ` [Qemu-devel] " Dong Jia Shi
2016-11-01 7:47 ` Kirti Wankhede
2016-11-01 7:47 ` [Qemu-devel] " Kirti Wankhede
2016-11-01 8:33 ` Dong Jia Shi
2016-11-01 8:33 ` Dong Jia Shi
2016-11-01 3:45 ` Dong Jia Shi
2016-10-31 3:50 ` Jike Song
2016-10-31 3:50 ` [Qemu-devel] " Jike Song
2016-10-31 5:59 ` Kirti Wankhede
2016-10-31 5:59 ` [Qemu-devel] " Kirti Wankhede
2016-10-31 6:05 ` Jike Song
2016-10-31 6:05 ` [Qemu-devel] " Jike Song
2016-10-26 21:29 ` [PATCH v10 11/19] vfio: Introduce common function to add capabilities Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 12/19] vfio_pci: Update vfio_pci to use vfio_info_add_capability() Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 13/19] vfio: Introduce vfio_set_irqs_validate_and_prepare() Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 14/19] vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare() Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 15/19] vfio_platform: " Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 16/19] vfio: Define device_api strings Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 17/19] docs: Add Documentation for Mediated devices Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 18/19] docs: Sysfs ABI for mediated device framework Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-31 7:19 ` Jike Song
2016-10-31 7:19 ` [Qemu-devel] " Jike Song
2016-11-02 7:55 ` Kirti Wankhede
2016-11-02 7:55 ` [Qemu-devel] " Kirti Wankhede
2016-10-26 21:29 ` [PATCH v10 19/19] docs: Sample driver to demonstrate how to use Mediated " Kirti Wankhede
2016-10-26 21:29 ` [Qemu-devel] " Kirti Wankhede
2016-10-27 14:29 ` Jonathan Corbet
2016-10-27 14:29 ` [Qemu-devel] " Jonathan Corbet
2016-11-01 8:32 ` [PATCH v10 00/19] Add Mediated device support Jike Song
2016-11-01 8:32 ` [Qemu-devel] " Jike Song
2016-11-01 15:24 ` Gerd Hoffmann
2016-11-01 15:24 ` [Qemu-devel] " Gerd Hoffmann
2016-11-02 1:01 ` Jike Song
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