[PATCH v3 0/9] vfio/fsl-mc: VFIO support for FSL-MC devices

[PATCH v3 0/9] vfio/fsl-mc: VFIO support for FSL-MC devices

[Diana Craciun]

DPAA2 (Data Path Acceleration Architecture) consists in
mechanisms for processing Ethernet packets, queue management,
accelerators, etc.

The Management Complex (mc) is a hardware entity that manages the DPAA2
hardware resources. It provides an object-based abstraction for software
drivers to use the DPAA2 hardware. The MC mediates operations such as
create, discover, destroy of DPAA2 objects.
The MC provides memory-mapped I/O command interfaces (MC portals) which
DPAA2 software drivers use to operate on DPAA2 objects.

A DPRC is a container object that holds other types of DPAA2 objects.
Each object in the DPRC is a Linux device and bound to a driver.
The MC-bus driver is a platform driver (different from PCI or platform
bus). The DPRC driver does runtime management of a bus instance. It
performs the initial scan of the DPRC and handles changes in the DPRC
configuration (adding/removing objects).

All objects inside a container share the same hardware isolation
context, meaning that only an entire DPRC can be assigned to
a virtual machine.
When a container is assigned to a virtual machine, all the objects
within that container are assigned to that virtual machine.
The DPRC container assigned to the virtual machine is not allowed
to change contents (add/remove objects) by the guest. The restriction
is set by the host and enforced by the mc hardware.

The DPAA2 objects can be directly assigned to the guest. However
the MC portals (the memory mapped command interface to the MC) need
to be emulated because there are commands that configure the
interrupts and the isolation IDs which are virtual in the guest.

Example:
echo vfio-fsl-mc > /sys/bus/fsl-mc/devices/dprc.2/driver_override
echo dprc.2 > /sys/bus/fsl-mc/drivers/vfio-fsl-mc/bind

The dprc.2 is bound to the VFIO driver and all the objects within
dprc.2 are going to be bound to the VFIO driver.

More details about the DPAA2 objects can be found here:
Documentation/networking/device_drivers/freescale/dpaa2/overview.rst

The patches are dependent on some changes in the mc-bus (bus/fsl-mc)
driver. The changes were needed in order to re-use code and to export
some more functions that are needed by the VFIO driver.
Currenlty the mc-bus patches are under review:
https://www.spinics.net/lists/kernel/msg3578910.html

v2 --> v3
- There is no need to align region size to page size
- read/write implemented for all DPAA2 objects
- review fixes

v1 --> v2
- Fixed the container reset, a new flag added to the firmware command
- Implement a bus notifier for setting driver_override

Bharat Bhushan (1):
  vfio/fsl-mc: Add VFIO framework skeleton for fsl-mc devices

Diana Craciun (8):
  vfio/fsl-mc: Scan DPRC objects on vfio-fsl-mc driver bind
  vfio/fsl-mc: Implement VFIO_DEVICE_GET_INFO ioctl
  vfio/fsl-mc: Implement VFIO_DEVICE_GET_REGION_INFO ioctl call
  vfio/fsl-mc: Allow userspace to MMAP fsl-mc device MMIO regions
  vfio/fsl-mc: Added lock support in preparation for interrupt handling
  vfio/fsl-mc: Add irq infrastructure for fsl-mc devices
  vfio/fsl-mc: trigger an interrupt via eventfd
  vfio/fsl-mc: Add read/write support for fsl-mc devices

 MAINTAINERS                               |   6 +
 drivers/vfio/Kconfig                      |   1 +
 drivers/vfio/Makefile                     |   1 +
 drivers/vfio/fsl-mc/Kconfig               |   9 +
 drivers/vfio/fsl-mc/Makefile              |   4 +
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 687 ++++++++++++++++++++++
 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c    | 221 +++++++
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |  55 ++
 include/uapi/linux/vfio.h                 |   1 +
 9 files changed, 985 insertions(+)
 create mode 100644 drivers/vfio/fsl-mc/Kconfig
 create mode 100644 drivers/vfio/fsl-mc/Makefile
 create mode 100644 drivers/vfio/fsl-mc/vfio_fsl_mc.c
 create mode 100644 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
 create mode 100644 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h

-- 
2.17.1

[PATCH v3 1/9] vfio/fsl-mc: Add VFIO framework skeleton for fsl-mc devices

[Diana Craciun]

From: Bharat Bhushan <Bharat.Bhushan@nxp.com>

DPAA2 (Data Path Acceleration Architecture) consists in
mechanisms for processing Ethernet packets, queue management,
accelerators, etc.

The Management Complex (mc) is a hardware entity that manages the DPAA2
hardware resources. It provides an object-based abstraction for software
drivers to use the DPAA2 hardware. The MC mediates operations such as
create, discover, destroy of DPAA2 objects.
The MC provides memory-mapped I/O command interfaces (MC portals) which
DPAA2 software drivers use to operate on DPAA2 objects.

A DPRC is a container object that holds other types of DPAA2 objects.
Each object in the DPRC is a Linux device and bound to a driver.
The MC-bus driver is a platform driver (different from PCI or platform
bus). The DPRC driver does runtime management of a bus instance. It
performs the initial scan of the DPRC and handles changes in the DPRC
configuration (adding/removing objects).

All objects inside a container share the same hardware isolation
context, meaning that only an entire DPRC can be assigned to
a virtual machine.
When a container is assigned to a virtual machine, all the objects
within that container are assigned to that virtual machine.
The DPRC container assigned to the virtual machine is not allowed
to change contents (add/remove objects) by the guest. The restriction
is set by the host and enforced by the mc hardware.

The DPAA2 objects can be directly assigned to the guest. However
the MC portals (the memory mapped command interface to the MC) need
to be emulated because there are commands that configure the
interrupts and the isolation IDs which are virtual in the guest.

Example:
echo vfio-fsl-mc > /sys/bus/fsl-mc/devices/dprc.2/driver_override
echo dprc.2 > /sys/bus/fsl-mc/drivers/vfio-fsl-mc/bind

The dprc.2 is bound to the VFIO driver and all the objects within
dprc.2 are going to be bound to the VFIO driver.

This patch adds the infrastructure for VFIO support for fsl-mc
devices. Subsequent patches will add support for binding and secure
assigning these devices using VFIO.

More details about the DPAA2 objects can be found here:
Documentation/networking/device_drivers/freescale/dpaa2/overview.rst

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 MAINTAINERS                               |   6 +
 drivers/vfio/Kconfig                      |   1 +
 drivers/vfio/Makefile                     |   1 +
 drivers/vfio/fsl-mc/Kconfig               |   9 ++
 drivers/vfio/fsl-mc/Makefile              |   4 +
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 160 ++++++++++++++++++++++
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |  14 ++
 include/uapi/linux/vfio.h                 |   1 +
 8 files changed, 196 insertions(+)
 create mode 100644 drivers/vfio/fsl-mc/Kconfig
 create mode 100644 drivers/vfio/fsl-mc/Makefile
 create mode 100644 drivers/vfio/fsl-mc/vfio_fsl_mc.c
 create mode 100644 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 1d4aa7f942de..18af3e530f8f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -18015,6 +18015,12 @@ F:	drivers/vfio/
 F:	include/linux/vfio.h
 F:	include/uapi/linux/vfio.h
 
+VFIO FSL-MC DRIVER
+M:	Diana Craciun <diana.craciun@oss.nxp.com>
+L:	kvm@vger.kernel.org
+S:	Maintained
+F:	drivers/vfio/fsl-mc/
+
 VFIO MEDIATED DEVICE DRIVERS
 M:	Kirti Wankhede <kwankhede@nvidia.com>
 L:	kvm@vger.kernel.org
diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
index fd17db9b432f..5533df91b257 100644
--- a/drivers/vfio/Kconfig
+++ b/drivers/vfio/Kconfig
@@ -47,4 +47,5 @@ menuconfig VFIO_NOIOMMU
 source "drivers/vfio/pci/Kconfig"
 source "drivers/vfio/platform/Kconfig"
 source "drivers/vfio/mdev/Kconfig"
+source "drivers/vfio/fsl-mc/Kconfig"
 source "virt/lib/Kconfig"
diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
index de67c4725cce..fee73f3d9480 100644
--- a/drivers/vfio/Makefile
+++ b/drivers/vfio/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_VFIO_SPAPR_EEH) += vfio_spapr_eeh.o
 obj-$(CONFIG_VFIO_PCI) += pci/
 obj-$(CONFIG_VFIO_PLATFORM) += platform/
 obj-$(CONFIG_VFIO_MDEV) += mdev/
+obj-$(CONFIG_VFIO_FSL_MC) += fsl-mc/
diff --git a/drivers/vfio/fsl-mc/Kconfig b/drivers/vfio/fsl-mc/Kconfig
new file mode 100644
index 000000000000..b1a527d6b6f2
--- /dev/null
+++ b/drivers/vfio/fsl-mc/Kconfig
@@ -0,0 +1,9 @@
+config VFIO_FSL_MC
+	tristate "VFIO support for QorIQ DPAA2 fsl-mc bus devices"
+	depends on VFIO && FSL_MC_BUS && EVENTFD
+	help
+	  Driver to enable support for the VFIO QorIQ DPAA2 fsl-mc
+	  (Management Complex) devices. This is required to passthrough
+	  fsl-mc bus devices using the VFIO framework.
+
+	  If you don't know what to do here, say N.
diff --git a/drivers/vfio/fsl-mc/Makefile b/drivers/vfio/fsl-mc/Makefile
new file mode 100644
index 000000000000..0c6e5d2ddaae
--- /dev/null
+++ b/drivers/vfio/fsl-mc/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+
+vfio-fsl-mc-y := vfio_fsl_mc.o
+obj-$(CONFIG_VFIO_FSL_MC) += vfio-fsl-mc.o
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
new file mode 100644
index 000000000000..8b53c2a25b32
--- /dev/null
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+/*
+ * Copyright 2013-2016 Freescale Semiconductor Inc.
+ * Copyright 2016-2017,2019-2020 NXP
+ */
+
+#include <linux/device.h>
+#include <linux/iommu.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/vfio.h>
+#include <linux/fsl/mc.h>
+
+#include "vfio_fsl_mc_private.h"
+
+static int vfio_fsl_mc_open(void *device_data)
+{
+	if (!try_module_get(THIS_MODULE))
+		return -ENODEV;
+
+	return 0;
+}
+
+static void vfio_fsl_mc_release(void *device_data)
+{
+	module_put(THIS_MODULE);
+}
+
+static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
+			      unsigned long arg)
+{
+	switch (cmd) {
+	case VFIO_DEVICE_GET_INFO:
+	{
+		return -ENOTTY;
+	}
+	case VFIO_DEVICE_GET_REGION_INFO:
+	{
+		return -ENOTTY;
+	}
+	case VFIO_DEVICE_GET_IRQ_INFO:
+	{
+		return -ENOTTY;
+	}
+	case VFIO_DEVICE_SET_IRQS:
+	{
+		return -ENOTTY;
+	}
+	case VFIO_DEVICE_RESET:
+	{
+		return -ENOTTY;
+	}
+	default:
+		return -ENOTTY;
+	}
+}
+
+static ssize_t vfio_fsl_mc_read(void *device_data, char __user *buf,
+				size_t count, loff_t *ppos)
+{
+	return -EINVAL;
+}
+
+static ssize_t vfio_fsl_mc_write(void *device_data, const char __user *buf,
+				 size_t count, loff_t *ppos)
+{
+	return -EINVAL;
+}
+
+static int vfio_fsl_mc_mmap(void *device_data, struct vm_area_struct *vma)
+{
+	return -EINVAL;
+}
+
+static const struct vfio_device_ops vfio_fsl_mc_ops = {
+	.name		= "vfio-fsl-mc",
+	.open		= vfio_fsl_mc_open,
+	.release	= vfio_fsl_mc_release,
+	.ioctl		= vfio_fsl_mc_ioctl,
+	.read		= vfio_fsl_mc_read,
+	.write		= vfio_fsl_mc_write,
+	.mmap		= vfio_fsl_mc_mmap,
+};
+
+static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
+{
+	struct iommu_group *group;
+	struct vfio_fsl_mc_device *vdev;
+	struct device *dev = &mc_dev->dev;
+	int ret;
+
+	group = vfio_iommu_group_get(dev);
+	if (!group) {
+		dev_err(dev, "%s: VFIO: No IOMMU group\n", __func__);
+		return -EINVAL;
+	}
+
+	vdev = devm_kzalloc(dev, sizeof(*vdev), GFP_KERNEL);
+	if (!vdev) {
+		vfio_iommu_group_put(group, dev);
+		return -ENOMEM;
+	}
+
+	vdev->mc_dev = mc_dev;
+
+	ret = vfio_add_group_dev(dev, &vfio_fsl_mc_ops, vdev);
+	if (ret) {
+		dev_err(dev, "%s: Failed to add to vfio group\n", __func__);
+		vfio_iommu_group_put(group, dev);
+		return ret;
+	}
+
+	return ret;
+}
+
+static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
+{
+	struct vfio_fsl_mc_device *vdev;
+	struct device *dev = &mc_dev->dev;
+
+	vdev = vfio_del_group_dev(dev);
+	if (!vdev)
+		return -EINVAL;
+
+	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
+
+	return 0;
+}
+
+/*
+ * vfio-fsl_mc is a meta-driver, so use driver_override interface to
+ * bind a fsl_mc container with this driver and match_id_table is NULL.
+ */
+static struct fsl_mc_driver vfio_fsl_mc_driver = {
+	.probe		= vfio_fsl_mc_probe,
+	.remove		= vfio_fsl_mc_remove,
+	.match_id_table = NULL,
+	.driver	= {
+		.name	= "vfio-fsl-mc",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init vfio_fsl_mc_driver_init(void)
+{
+	return fsl_mc_driver_register(&vfio_fsl_mc_driver);
+}
+
+static void __exit vfio_fsl_mc_driver_exit(void)
+{
+	fsl_mc_driver_unregister(&vfio_fsl_mc_driver);
+}
+
+module_init(vfio_fsl_mc_driver_init);
+module_exit(vfio_fsl_mc_driver_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("VFIO for FSL-MC devices - User Level meta-driver");
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
new file mode 100644
index 000000000000..e79cc116f6b8
--- /dev/null
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) */
+/*
+ * Copyright 2013-2016 Freescale Semiconductor Inc.
+ * Copyright 2016,2019-2020 NXP
+ */
+
+#ifndef VFIO_FSL_MC_PRIVATE_H
+#define VFIO_FSL_MC_PRIVATE_H
+
+struct vfio_fsl_mc_device {
+	struct fsl_mc_device		*mc_dev;
+};
+
+#endif /* VFIO_FSL_MC_PRIVATE_H */
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 920470502329..95deac891378 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -201,6 +201,7 @@ struct vfio_device_info {
 #define VFIO_DEVICE_FLAGS_AMBA  (1 << 3)	/* vfio-amba device */
 #define VFIO_DEVICE_FLAGS_CCW	(1 << 4)	/* vfio-ccw device */
 #define VFIO_DEVICE_FLAGS_AP	(1 << 5)	/* vfio-ap device */
+#define VFIO_DEVICE_FLAGS_FSL_MC (1 << 6)	/* vfio-fsl-mc device */
 	__u32	num_regions;	/* Max region index + 1 */
 	__u32	num_irqs;	/* Max IRQ index + 1 */
 };
-- 
2.17.1

[PATCH v3 2/9] vfio/fsl-mc: Scan DPRC objects on vfio-fsl-mc driver bind

[Diana Craciun]

The DPRC (Data Path Resource Container) device is a bus device and has
child devices attached to it. When the vfio-fsl-mc driver is probed
the DPRC is scanned and the child devices discovered and initialized.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 106 ++++++++++++++++++++++
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |   1 +
 2 files changed, 107 insertions(+)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 8b53c2a25b32..ad8d06cceb71 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -15,6 +15,8 @@
 
 #include "vfio_fsl_mc_private.h"
 
+static struct fsl_mc_driver vfio_fsl_mc_driver;
+
 static int vfio_fsl_mc_open(void *device_data)
 {
 	if (!try_module_get(THIS_MODULE))
@@ -84,6 +86,69 @@ static const struct vfio_device_ops vfio_fsl_mc_ops = {
 	.mmap		= vfio_fsl_mc_mmap,
 };
 
+static int vfio_fsl_mc_bus_notifier(struct notifier_block *nb,
+				    unsigned long action, void *data)
+{
+	struct vfio_fsl_mc_device *vdev = container_of(nb,
+					struct vfio_fsl_mc_device, nb);
+	struct device *dev = data;
+	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
+	struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);
+
+	if (action == BUS_NOTIFY_ADD_DEVICE &&
+	    vdev->mc_dev == mc_cont) {
+		mc_dev->driver_override = kasprintf(GFP_KERNEL, "%s",
+						    vfio_fsl_mc_ops.name);
+		dev_info(dev, "Setting driver override for device in dprc %s\n",
+			 dev_name(&mc_cont->dev));
+	} else if (action == BUS_NOTIFY_BOUND_DRIVER &&
+		vdev->mc_dev == mc_cont) {
+		struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver);
+
+		if (mc_drv && mc_drv != &vfio_fsl_mc_driver)
+			dev_warn(dev, "Object %s bound to driver %s while DPRC bound to vfio-fsl-mc\n",
+				 dev_name(dev), mc_drv->driver.name);
+		}
+
+	return 0;
+}
+
+static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	int ret;
+
+	/* Non-dprc devices share mc_io from parent */
+	if (!is_fsl_mc_bus_dprc(mc_dev)) {
+		struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);
+
+		mc_dev->mc_io = mc_cont->mc_io;
+		return 0;
+	}
+
+	vdev->nb.notifier_call = vfio_fsl_mc_bus_notifier;
+	ret = bus_register_notifier(&fsl_mc_bus_type, &vdev->nb);
+	if (ret)
+		return ret;
+
+	/* open DPRC, allocate a MC portal */
+	ret = dprc_setup(mc_dev);
+	if (ret < 0) {
+		dev_err(&mc_dev->dev, "Failed to setup DPRC (error = %d)\n", ret);
+		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
+		return ret;
+	}
+
+	ret = dprc_scan_container(mc_dev, false);
+	if (ret < 0) {
+		dev_err(&mc_dev->dev, "Container scanning failed: %d\n", ret);
+		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
+		dprc_cleanup(mc_dev);
+	}
+
+	return ret;
+}
+
 static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 {
 	struct iommu_group *group;
@@ -112,9 +177,42 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 		return ret;
 	}
 
+	ret = vfio_fsl_mc_init_device(vdev);
+	if (ret < 0) {
+		vfio_iommu_group_put(group, dev);
+		return ret;
+	}
+
 	return ret;
 }
 
+static int vfio_fsl_mc_device_remove(struct device *dev, void *data)
+{
+	struct fsl_mc_device *mc_dev;
+
+	WARN_ON(!dev);
+	mc_dev = to_fsl_mc_device(dev);
+	if (WARN_ON(!mc_dev))
+		return -ENODEV;
+
+	kfree(mc_dev->driver_override);
+	mc_dev->driver_override = NULL;
+
+	/*
+	 * The device-specific remove callback will get invoked by device_del()
+	 */
+	device_del(&mc_dev->dev);
+	put_device(&mc_dev->dev);
+
+	return 0;
+}
+
+static void vfio_fsl_mc_cleanup_dprc(struct fsl_mc_device *mc_dev)
+{
+	device_for_each_child(&mc_dev->dev, NULL, vfio_fsl_mc_device_remove);
+	dprc_cleanup(mc_dev);
+}
+
 static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 {
 	struct vfio_fsl_mc_device *vdev;
@@ -124,6 +222,14 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 	if (!vdev)
 		return -EINVAL;
 
+	if (vdev->nb.notifier_call)
+		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
+
+	if (is_fsl_mc_bus_dprc(mc_dev))
+		vfio_fsl_mc_cleanup_dprc(vdev->mc_dev);
+
+	mc_dev->mc_io = NULL;
+
 	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
 
 	return 0;
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index e79cc116f6b8..37d61eaa58c8 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -9,6 +9,7 @@
 
 struct vfio_fsl_mc_device {
 	struct fsl_mc_device		*mc_dev;
+	struct notifier_block        nb;
 };
 
 #endif /* VFIO_FSL_MC_PRIVATE_H */
-- 
2.17.1

[PATCH v3 3/9] vfio/fsl-mc: Implement VFIO_DEVICE_GET_INFO ioctl

[Diana Craciun]

Allow userspace to get fsl-mc device info (number of regions
and irqs).

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index ad8d06cceb71..937b6eddc71a 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -33,10 +33,29 @@ static void vfio_fsl_mc_release(void *device_data)
 static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
 			      unsigned long arg)
 {
+	unsigned long minsz;
+	struct vfio_fsl_mc_device *vdev = device_data;
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+
 	switch (cmd) {
 	case VFIO_DEVICE_GET_INFO:
 	{
-		return -ENOTTY;
+		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;
+
+		info.flags = VFIO_DEVICE_FLAGS_FSL_MC;
+		info.num_regions = mc_dev->obj_desc.region_count;
+		info.num_irqs = mc_dev->obj_desc.irq_count;
+
+		return copy_to_user((void __user *)arg, &info, minsz) ?
+			-EFAULT : 0;
 	}
 	case VFIO_DEVICE_GET_REGION_INFO:
 	{
-- 
2.17.1

[PATCH v3 4/9] vfio/fsl-mc: Implement VFIO_DEVICE_GET_REGION_INFO ioctl call

[Diana Craciun]

Expose to userspace information about the memory regions.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 77 ++++++++++++++++++++++-
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 19 ++++++
 2 files changed, 95 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 937b6eddc71a..10bd9f78b8de 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -17,16 +17,72 @@
 
 static struct fsl_mc_driver vfio_fsl_mc_driver;
 
+static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	int count = mc_dev->obj_desc.region_count;
+	int i;
+
+	vdev->regions = kcalloc(count, sizeof(struct vfio_fsl_mc_region),
+				GFP_KERNEL);
+	if (!vdev->regions)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		struct resource *res = &mc_dev->regions[i];
+
+		vdev->regions[i].addr = res->start;
+		vdev->regions[i].size = resource_size(res);
+		vdev->regions[i].flags = 0;
+	}
+
+	vdev->num_regions = mc_dev->obj_desc.region_count;
+	return 0;
+}
+
+static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev)
+{
+	vdev->num_regions = 0;
+	kfree(vdev->regions);
+}
+
 static int vfio_fsl_mc_open(void *device_data)
 {
+	struct vfio_fsl_mc_device *vdev = device_data;
+	int ret;
+
 	if (!try_module_get(THIS_MODULE))
 		return -ENODEV;
 
+	mutex_lock(&vdev->driver_lock);
+	if (!vdev->refcnt) {
+		ret = vfio_fsl_mc_regions_init(vdev);
+		if (ret)
+			goto err_reg_init;
+	}
+	vdev->refcnt++;
+
+	mutex_unlock(&vdev->driver_lock);
+
 	return 0;
+
+err_reg_init:
+	mutex_unlock(&vdev->driver_lock);
+	module_put(THIS_MODULE);
+	return ret;
 }
 
 static void vfio_fsl_mc_release(void *device_data)
 {
+	struct vfio_fsl_mc_device *vdev = device_data;
+
+	mutex_lock(&vdev->driver_lock);
+
+	if (!(--vdev->refcnt))
+		vfio_fsl_mc_regions_cleanup(vdev);
+
+	mutex_unlock(&vdev->driver_lock);
+
 	module_put(THIS_MODULE);
 }
 
@@ -59,7 +115,25 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
 	}
 	case VFIO_DEVICE_GET_REGION_INFO:
 	{
-		return -ENOTTY;
+		struct vfio_region_info info;
+
+		minsz = offsetofend(struct vfio_region_info, offset);
+
+		if (copy_from_user(&info, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (info.argsz < minsz)
+			return -EINVAL;
+
+		if (info.index >= vdev->num_regions)
+			return -EINVAL;
+
+		/* map offset to the physical address  */
+		info.offset = VFIO_FSL_MC_INDEX_TO_OFFSET(info.index);
+		info.size = vdev->regions[info.index].size;
+		info.flags = vdev->regions[info.index].flags;
+
+		return copy_to_user((void __user *)arg, &info, minsz);
 	}
 	case VFIO_DEVICE_GET_IRQ_INFO:
 	{
@@ -201,6 +275,7 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 		vfio_iommu_group_put(group, dev);
 		return ret;
 	}
+	mutex_init(&vdev->driver_lock);
 
 	return ret;
 }
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index 37d61eaa58c8..818dfd3df4db 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -7,9 +7,28 @@
 #ifndef VFIO_FSL_MC_PRIVATE_H
 #define VFIO_FSL_MC_PRIVATE_H
 
+#define VFIO_FSL_MC_OFFSET_SHIFT    40
+#define VFIO_FSL_MC_OFFSET_MASK (((u64)(1) << VFIO_FSL_MC_OFFSET_SHIFT) - 1)
+
+#define VFIO_FSL_MC_OFFSET_TO_INDEX(off) ((off) >> VFIO_FSL_MC_OFFSET_SHIFT)
+
+#define VFIO_FSL_MC_INDEX_TO_OFFSET(index)	\
+	((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
+
+struct vfio_fsl_mc_region {
+	u32			flags;
+	u32			type;
+	u64			addr;
+	resource_size_t		size;
+};
+
 struct vfio_fsl_mc_device {
 	struct fsl_mc_device		*mc_dev;
 	struct notifier_block        nb;
+	int				refcnt;
+	u32				num_regions;
+	struct vfio_fsl_mc_region	*regions;
+	struct mutex driver_lock;
 };
 
 #endif /* VFIO_FSL_MC_PRIVATE_H */
-- 
2.17.1

[PATCH v3 5/9] vfio/fsl-mc: Allow userspace to MMAP fsl-mc device MMIO regions

[Diana Craciun]

Allow userspace to mmap device regions for direct access of
fsl-mc devices.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c | 59 +++++++++++++++++++++++++++++--
 1 file changed, 57 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 10bd9f78b8de..37ccc7d2acbc 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -33,7 +33,8 @@ static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
 
 		vdev->regions[i].addr = res->start;
 		vdev->regions[i].size = resource_size(res);
-		vdev->regions[i].flags = 0;
+		vdev->regions[i].flags = VFIO_REGION_INFO_FLAG_MMAP;
+		vdev->regions[i].type = mc_dev->regions[i].flags & IORESOURCE_BITS;
 	}
 
 	vdev->num_regions = mc_dev->obj_desc.region_count;
@@ -164,9 +165,63 @@ static ssize_t vfio_fsl_mc_write(void *device_data, const char __user *buf,
 	return -EINVAL;
 }
 
+static int vfio_fsl_mc_mmap_mmio(struct vfio_fsl_mc_region region,
+				 struct vm_area_struct *vma)
+{
+	u64 size = vma->vm_end - vma->vm_start;
+	u64 pgoff, base;
+	u8 region_cacheable;
+
+	pgoff = vma->vm_pgoff &
+		((1U << (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
+	base = pgoff << PAGE_SHIFT;
+
+	if (region.size < PAGE_SIZE || base + size > region.size)
+		return -EINVAL;
+
+	region_cacheable = (region.type & FSL_MC_REGION_CACHEABLE) && (region.type & FSL_MC_REGION_SHAREABLE);
+	if (!region_cacheable)
+		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
+
+	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+			       size, vma->vm_page_prot);
+}
+
 static int vfio_fsl_mc_mmap(void *device_data, struct vm_area_struct *vma)
 {
-	return -EINVAL;
+	struct vfio_fsl_mc_device *vdev = device_data;
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	int index;
+
+	index = vma->vm_pgoff >> (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT);
+
+	if (vma->vm_end < vma->vm_start)
+		return -EINVAL;
+	if (vma->vm_start & ~PAGE_MASK)
+		return -EINVAL;
+	if (vma->vm_end & ~PAGE_MASK)
+		return -EINVAL;
+	if (!(vma->vm_flags & VM_SHARED))
+		return -EINVAL;
+	if (index >= vdev->num_regions)
+		return -EINVAL;
+
+	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
+		return -EINVAL;
+
+	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
+			&& (vma->vm_flags & VM_READ))
+		return -EINVAL;
+
+	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
+			&& (vma->vm_flags & VM_WRITE))
+		return -EINVAL;
+
+	vma->vm_private_data = mc_dev;
+
+	return vfio_fsl_mc_mmap_mmio(vdev->regions[index], vma);
 }
 
 static const struct vfio_device_ops vfio_fsl_mc_ops = {
-- 
2.17.1

[PATCH v3 6/9] vfio/fsl-mc: Added lock support in preparation for interrupt handling

[Diana Craciun]

From: Diana Craciun <diana.craciun@nxp.com>

Only the DPRC object allocates interrupts from the MSI
interrupt domain. The interrupts are managed by the DPRC in
a pool of interrupts. The access to this pool of interrupts
has to be protected with a lock.
This patch extends the current lock implementation to have a
lock per DPRC.

Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 90 +++++++++++++++++++++--
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |  8 +-
 2 files changed, 91 insertions(+), 7 deletions(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 37ccc7d2acbc..275c4283e1bc 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -17,6 +17,76 @@
 
 static struct fsl_mc_driver vfio_fsl_mc_driver;
 
+static DEFINE_MUTEX(reflck_lock);
+
+static void vfio_fsl_mc_reflck_get(struct vfio_fsl_mc_reflck *reflck)
+{
+	kref_get(&reflck->kref);
+}
+
+static void vfio_fsl_mc_reflck_release(struct kref *kref)
+{
+	struct vfio_fsl_mc_reflck *reflck = container_of(kref,
+						      struct vfio_fsl_mc_reflck,
+						      kref);
+
+	kfree(reflck);
+	mutex_unlock(&reflck_lock);
+}
+
+static void vfio_fsl_mc_reflck_put(struct vfio_fsl_mc_reflck *reflck)
+{
+	kref_put_mutex(&reflck->kref, vfio_fsl_mc_reflck_release, &reflck_lock);
+}
+
+static struct vfio_fsl_mc_reflck *vfio_fsl_mc_reflck_alloc(void)
+{
+	struct vfio_fsl_mc_reflck *reflck;
+
+	reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
+	if (!reflck)
+		return ERR_PTR(-ENOMEM);
+
+	kref_init(&reflck->kref);
+	mutex_init(&reflck->lock);
+
+	return reflck;
+}
+
+static int vfio_fsl_mc_reflck_attach(struct vfio_fsl_mc_device *vdev)
+{
+	int ret = 0;
+
+	mutex_lock(&reflck_lock);
+	if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
+		vdev->reflck = vfio_fsl_mc_reflck_alloc();
+	} else {
+		struct device *mc_cont_dev = vdev->mc_dev->dev.parent;
+		struct vfio_device *device;
+		struct vfio_fsl_mc_device *cont_vdev;
+
+		device = vfio_device_get_from_dev(mc_cont_dev);
+		if (!device) {
+			ret = -ENODEV;
+			goto unlock;
+		}
+
+		cont_vdev = vfio_device_data(device);
+		if (!cont_vdev->reflck) {
+			vfio_device_put(device);
+			ret = -ENODEV;
+			goto unlock;
+		}
+		vfio_fsl_mc_reflck_get(cont_vdev->reflck);
+		vdev->reflck = cont_vdev->reflck;
+		vfio_device_put(device);
+	}
+
+unlock:
+	mutex_unlock(&reflck_lock);
+	return ret;
+}
+
 static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
 {
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
@@ -55,7 +125,7 @@ static int vfio_fsl_mc_open(void *device_data)
 	if (!try_module_get(THIS_MODULE))
 		return -ENODEV;
 
-	mutex_lock(&vdev->driver_lock);
+	mutex_lock(&vdev->reflck->lock);
 	if (!vdev->refcnt) {
 		ret = vfio_fsl_mc_regions_init(vdev);
 		if (ret)
@@ -63,12 +133,12 @@ static int vfio_fsl_mc_open(void *device_data)
 	}
 	vdev->refcnt++;
 
-	mutex_unlock(&vdev->driver_lock);
+	mutex_unlock(&vdev->reflck->lock);
 
 	return 0;
 
 err_reg_init:
-	mutex_unlock(&vdev->driver_lock);
+	mutex_unlock(&vdev->reflck->lock);
 	module_put(THIS_MODULE);
 	return ret;
 }
@@ -77,12 +147,12 @@ static void vfio_fsl_mc_release(void *device_data)
 {
 	struct vfio_fsl_mc_device *vdev = device_data;
 
-	mutex_lock(&vdev->driver_lock);
+	mutex_lock(&vdev->reflck->lock);
 
 	if (!(--vdev->refcnt))
 		vfio_fsl_mc_regions_cleanup(vdev);
 
-	mutex_unlock(&vdev->driver_lock);
+	mutex_unlock(&vdev->reflck->lock);
 
 	module_put(THIS_MODULE);
 }
@@ -325,12 +395,18 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 		return ret;
 	}
 
+	ret = vfio_fsl_mc_reflck_attach(vdev);
+	if (ret) {
+		vfio_iommu_group_put(group, dev);
+		return ret;
+	}
+
 	ret = vfio_fsl_mc_init_device(vdev);
 	if (ret < 0) {
+		vfio_fsl_mc_reflck_put(vdev->reflck);
 		vfio_iommu_group_put(group, dev);
 		return ret;
 	}
-	mutex_init(&vdev->driver_lock);
 
 	return ret;
 }
@@ -374,6 +450,8 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 	if (vdev->nb.notifier_call)
 		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
 
+	vfio_fsl_mc_reflck_put(vdev->reflck);
+
 	if (is_fsl_mc_bus_dprc(mc_dev))
 		vfio_fsl_mc_cleanup_dprc(vdev->mc_dev);
 
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index 818dfd3df4db..3b85d930e060 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -15,6 +15,11 @@
 #define VFIO_FSL_MC_INDEX_TO_OFFSET(index)	\
 	((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
 
+struct vfio_fsl_mc_reflck {
+	struct kref		kref;
+	struct mutex		lock;
+};
+
 struct vfio_fsl_mc_region {
 	u32			flags;
 	u32			type;
@@ -28,7 +33,8 @@ struct vfio_fsl_mc_device {
 	int				refcnt;
 	u32				num_regions;
 	struct vfio_fsl_mc_region	*regions;
-	struct mutex driver_lock;
+	struct vfio_fsl_mc_reflck   *reflck;
+
 };
 
 #endif /* VFIO_FSL_MC_PRIVATE_H */
-- 
2.17.1

[PATCH v3 7/9] vfio/fsl-mc: Add irq infrastructure for fsl-mc devices

[Diana Craciun]

This patch adds the skeleton for interrupt support
for fsl-mc devices. The interrupts are not yet functional,
the functionality will be added by subsequent patches.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/vfio/fsl-mc/Makefile              |  2 +-
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 71 ++++++++++++++++++++++-
 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c    | 63 ++++++++++++++++++++
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |  5 ++
 4 files changed, 138 insertions(+), 3 deletions(-)
 create mode 100644 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c

diff --git a/drivers/vfio/fsl-mc/Makefile b/drivers/vfio/fsl-mc/Makefile
index 0c6e5d2ddaae..cad6dbf0b735 100644
--- a/drivers/vfio/fsl-mc/Makefile
+++ b/drivers/vfio/fsl-mc/Makefile
@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
 
-vfio-fsl-mc-y := vfio_fsl_mc.o
+vfio-fsl-mc-y := vfio_fsl_mc.o vfio_fsl_mc_intr.o
 obj-$(CONFIG_VFIO_FSL_MC) += vfio-fsl-mc.o
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 275c4283e1bc..2ce17d297145 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -208,11 +208,75 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
 	}
 	case VFIO_DEVICE_GET_IRQ_INFO:
 	{
-		return -ENOTTY;
+		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)
+			return -EINVAL;
+
+		if (info.index >= mc_dev->obj_desc.irq_count)
+			return -EINVAL;
+
+		info.flags = VFIO_IRQ_INFO_EVENTFD;
+		info.count = 1;
+
+		return copy_to_user((void __user *)arg, &info, minsz);
 	}
 	case VFIO_DEVICE_SET_IRQS:
 	{
-		return -ENOTTY;
+		struct vfio_irq_set hdr;
+		u8 *data = NULL;
+		int ret = 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 >= mc_dev->obj_desc.irq_count)
+			return -EINVAL;
+
+		if (hdr.start != 0 || hdr.count > 1)
+			return -EINVAL;
+
+		if (hdr.count == 0 &&
+		    (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE) ||
+		    !(hdr.flags & VFIO_IRQ_SET_ACTION_TRIGGER)))
+			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 < hdr.count * size)
+				return -EINVAL;
+
+			data = memdup_user((void __user *)(arg + minsz),
+					   hdr.count * size);
+			if (IS_ERR(data))
+				return PTR_ERR(data);
+		}
+
+		ret = vfio_fsl_mc_set_irqs_ioctl(vdev, hdr.flags,
+						 hdr.index, hdr.start,
+						 hdr.count, data);
+		return ret;
 	}
 	case VFIO_DEVICE_RESET:
 	{
@@ -336,6 +400,9 @@ static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	int ret;
 
+	/* innherit the msi domain from parent */
+	dev_set_msi_domain(&mc_dev->dev, dev_get_msi_domain(mc_dev->dev.parent));
+
 	/* Non-dprc devices share mc_io from parent */
 	if (!is_fsl_mc_bus_dprc(mc_dev)) {
 		struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
new file mode 100644
index 000000000000..058aa97aa54a
--- /dev/null
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+/*
+ * Copyright 2013-2016 Freescale Semiconductor Inc.
+ * Copyright 2019 NXP
+ */
+
+#include <linux/vfio.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/eventfd.h>
+#include <linux/msi.h>
+
+#include "linux/fsl/mc.h"
+#include "vfio_fsl_mc_private.h"
+
+static int vfio_fsl_mc_irq_mask(struct vfio_fsl_mc_device *vdev,
+				unsigned int index, unsigned int start,
+				unsigned int count, u32 flags,
+				void *data)
+{
+	return -EINVAL;
+}
+
+static int vfio_fsl_mc_irq_unmask(struct vfio_fsl_mc_device *vdev,
+				unsigned int index, unsigned int start,
+				unsigned int count, u32 flags,
+				void *data)
+{
+	return -EINVAL;
+}
+
+static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
+				       unsigned int index, unsigned int start,
+				       unsigned int count, u32 flags,
+				       void *data)
+{
+	return -EINVAL;
+}
+
+int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
+			       u32 flags, unsigned int index,
+			       unsigned int start, unsigned int count,
+			       void *data)
+{
+	int ret = -ENOTTY;
+
+	switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
+	case VFIO_IRQ_SET_ACTION_MASK:
+		ret = vfio_fsl_mc_irq_mask(vdev, index, start, count,
+					   flags, data);
+		break;
+	case VFIO_IRQ_SET_ACTION_UNMASK:
+		ret = vfio_fsl_mc_irq_unmask(vdev, index, start, count,
+					     flags, data);
+		break;
+	case VFIO_IRQ_SET_ACTION_TRIGGER:
+		ret = vfio_fsl_mc_set_irq_trigger(vdev, index, start,
+						  count, flags, data);
+		break;
+	}
+
+	return ret;
+}
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index 3b85d930e060..dd94be84a3d0 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -37,4 +37,9 @@ struct vfio_fsl_mc_device {
 
 };
 
+extern int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
+			       u32 flags, unsigned int index,
+			       unsigned int start, unsigned int count,
+			       void *data);
+
 #endif /* VFIO_FSL_MC_PRIVATE_H */
-- 
2.17.1

[PATCH v3 8/9] vfio/fsl-mc: trigger an interrupt via eventfd

[Diana Craciun]

This patch allows to set an eventfd for fsl-mc device interrupts
and also to trigger the interrupt eventfd from userspace for testing.

All fsl-mc device interrupts are MSIs. The MSIs are allocated from
the MSI domain only once per DPRC and used by all the DPAA2 objects.
The interrupts are managed by the DPRC in a pool of interrupts. Each
device requests interrupts from this pool. The pool is allocated
when the first virtual device is setting the interrupts.
The pool of interrupts is protected by a lock.

The DPRC has an interrupt of its own which indicates if the DPRC
contents have changed. However, currently, the contents of a DPRC
assigned to the guest cannot be changed at runtime, so this interrupt
is not configured.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         |  18 ++-
 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c    | 160 +++++++++++++++++++++-
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |  11 +-
 3 files changed, 186 insertions(+), 3 deletions(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 2ce17d297145..0c2d4f11dc43 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -146,12 +146,28 @@ static int vfio_fsl_mc_open(void *device_data)
 static void vfio_fsl_mc_release(void *device_data)
 {
 	struct vfio_fsl_mc_device *vdev = device_data;
+	int ret;
 
 	mutex_lock(&vdev->reflck->lock);
 
-	if (!(--vdev->refcnt))
+	if (!(--vdev->refcnt)) {
+		struct fsl_mc_device *mc_dev = vdev->mc_dev;
+		struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
+		struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
+
 		vfio_fsl_mc_regions_cleanup(vdev);
 
+		/* reset the device before cleaning up the interrupts */
+		ret = dprc_reset_container(mc_cont->mc_io, 0,
+		      mc_cont->mc_handle,
+			  mc_cont->obj_desc.id,
+			  DPRC_RESET_OPTION_NON_RECURSIVE);
+
+		vfio_fsl_mc_irqs_cleanup(vdev);
+
+		fsl_mc_cleanup_irq_pool(mc_cont);
+	}
+
 	mutex_unlock(&vdev->reflck->lock);
 
 	module_put(THIS_MODULE);
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
index 058aa97aa54a..409f3507fcf3 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
@@ -29,12 +29,149 @@ static int vfio_fsl_mc_irq_unmask(struct vfio_fsl_mc_device *vdev,
 	return -EINVAL;
 }
 
+int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	struct vfio_fsl_mc_irq *mc_irq;
+	int irq_count;
+	int ret, i;
+
+    /* Device does not support any interrupt */
+	if (mc_dev->obj_desc.irq_count == 0)
+		return 0;
+
+	/* interrupts were already allocated for this device */
+	if (vdev->mc_irqs)
+		return 0;
+
+	irq_count = mc_dev->obj_desc.irq_count;
+
+	mc_irq = kcalloc(irq_count, sizeof(*mc_irq), GFP_KERNEL);
+	if (!mc_irq)
+		return -ENOMEM;
+
+	/* Allocate IRQs */
+	ret = fsl_mc_allocate_irqs(mc_dev);
+	if (ret) {
+		kfree(mc_irq);
+		return ret;
+	}
+
+	for (i = 0; i < irq_count; i++) {
+		mc_irq[i].count = 1;
+		mc_irq[i].flags = VFIO_IRQ_INFO_EVENTFD;
+	}
+
+	vdev->mc_irqs = mc_irq;
+
+	return 0;
+}
+
+static irqreturn_t vfio_fsl_mc_irq_handler(int irq_num, void *arg)
+{
+	struct vfio_fsl_mc_irq *mc_irq = (struct vfio_fsl_mc_irq *)arg;
+
+	eventfd_signal(mc_irq->trigger, 1);
+	return IRQ_HANDLED;
+}
+
+static int vfio_set_trigger(struct vfio_fsl_mc_device *vdev,
+						   int index, int fd)
+{
+	struct vfio_fsl_mc_irq *irq = &vdev->mc_irqs[index];
+	struct eventfd_ctx *trigger;
+	int hwirq;
+	int ret;
+
+	hwirq = vdev->mc_dev->irqs[index]->msi_desc->irq;
+	if (irq->trigger) {
+		free_irq(hwirq, irq);
+		kfree(irq->name);
+		eventfd_ctx_put(irq->trigger);
+		irq->trigger = NULL;
+	}
+
+	if (fd < 0) /* Disable only */
+		return 0;
+
+	irq->name = kasprintf(GFP_KERNEL, "vfio-irq[%d](%s)",
+			    hwirq, dev_name(&vdev->mc_dev->dev));
+	if (!irq->name)
+		return -ENOMEM;
+
+	trigger = eventfd_ctx_fdget(fd);
+	if (IS_ERR(trigger)) {
+		kfree(irq->name);
+		return PTR_ERR(trigger);
+	}
+
+	irq->trigger = trigger;
+
+	ret = request_irq(hwirq, vfio_fsl_mc_irq_handler, 0,
+		  irq->name, irq);
+	if (ret) {
+		kfree(irq->name);
+		eventfd_ctx_put(trigger);
+		irq->trigger = NULL;
+		return ret;
+	}
+
+	return 0;
+}
+
 static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
 				       unsigned int index, unsigned int start,
 				       unsigned int count, u32 flags,
 				       void *data)
 {
-	return -EINVAL;
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	int ret, hwirq;
+	struct vfio_fsl_mc_irq *irq;
+	struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
+	struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
+
+	if (start != 0 || count != 1)
+		return -EINVAL;
+
+	mutex_lock(&vdev->reflck->lock);
+	ret = fsl_mc_populate_irq_pool(mc_cont,
+			FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
+	if (ret)
+		goto unlock;
+
+	ret = vfio_fsl_mc_irqs_allocate(vdev);
+	if (ret)
+		goto unlock;
+	mutex_unlock(&vdev->reflck->lock);
+
+	if (!count && (flags & VFIO_IRQ_SET_DATA_NONE))
+		return vfio_set_trigger(vdev, index, -1);
+
+	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+		s32 fd = *(s32 *)data;
+
+		return vfio_set_trigger(vdev, index, fd);
+	}
+
+	hwirq = vdev->mc_dev->irqs[index]->msi_desc->irq;
+
+	irq = &vdev->mc_irqs[index];
+
+	if (flags & VFIO_IRQ_SET_DATA_NONE) {
+		vfio_fsl_mc_irq_handler(hwirq, irq);
+
+	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
+		u8 trigger = *(u8 *)data;
+
+		if (trigger)
+			vfio_fsl_mc_irq_handler(hwirq, irq);
+	}
+
+	return 0;
+
+unlock:
+	mutex_unlock(&vdev->reflck->lock);
+	return ret;
 }
 
 int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
@@ -61,3 +198,24 @@ int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
 
 	return ret;
 }
+
+/* Free All IRQs for the given MC object */
+void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	int irq_count = mc_dev->obj_desc.irq_count;
+	int i;
+
+	/* Device does not support any interrupt or the interrupts
+	 * were not configured
+	 */
+	if (mc_dev->obj_desc.irq_count == 0 || !vdev->mc_irqs)
+		return;
+
+	for (i = 0; i < irq_count; i++)
+		vfio_set_trigger(vdev, i, -1);
+
+	fsl_mc_free_irqs(mc_dev);
+	kfree(vdev->mc_irqs);
+	vdev->mc_irqs = NULL;
+}
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index dd94be84a3d0..1f9b518c520d 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -15,6 +15,13 @@
 #define VFIO_FSL_MC_INDEX_TO_OFFSET(index)	\
 	((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
 
+struct vfio_fsl_mc_irq {
+	u32         flags;
+	u32         count;
+	struct eventfd_ctx  *trigger;
+	char            *name;
+};
+
 struct vfio_fsl_mc_reflck {
 	struct kref		kref;
 	struct mutex		lock;
@@ -34,7 +41,7 @@ struct vfio_fsl_mc_device {
 	u32				num_regions;
 	struct vfio_fsl_mc_region	*regions;
 	struct vfio_fsl_mc_reflck   *reflck;
-
+	struct vfio_fsl_mc_irq      *mc_irqs;
 };
 
 extern int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
@@ -42,4 +49,6 @@ extern int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
 			       unsigned int start, unsigned int count,
 			       void *data);
 
+void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev);
+
 #endif /* VFIO_FSL_MC_PRIVATE_H */
-- 
2.17.1

[PATCH v3 9/9] vfio/fsl-mc: Add read/write support for fsl-mc devices

[Diana Craciun]

The software uses a memory-mapped I/O command interface (MC portals) to
communicate with the MC hardware. This command interface is used to
discover, enumerate, configure and remove DPAA2 objects. The DPAA2
objects use MSIs, so the command interface needs to be emulated
such that the correct MSI is configured in the hardware (the guest
has the virtual MSIs).

This patch is adding read/write support for fsl-mc devices. The mc
commands are emulated by the userspace. The host is just passing
the correct command to the hardware.

Also the current patch limits userspace to write complete
64byte command once and read 64byte response by one ioctl.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 115 +++++++++++++++++++++-
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |   1 +
 2 files changed, 114 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 0c2d4f11dc43..104e3bb78bf8 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -12,6 +12,7 @@
 #include <linux/types.h>
 #include <linux/vfio.h>
 #include <linux/fsl/mc.h>
+#include <linux/delay.h>
 
 #include "vfio_fsl_mc_private.h"
 
@@ -105,6 +106,9 @@ static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
 		vdev->regions[i].size = resource_size(res);
 		vdev->regions[i].flags = VFIO_REGION_INFO_FLAG_MMAP;
 		vdev->regions[i].type = mc_dev->regions[i].flags & IORESOURCE_BITS;
+		vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
+		if (!(mc_dev->regions[i].flags & IORESOURCE_READONLY))
+			vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_WRITE;
 	}
 
 	vdev->num_regions = mc_dev->obj_desc.region_count;
@@ -113,6 +117,11 @@ static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
 
 static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev)
 {
+	int i;
+
+	for (i = 0; i < vdev->num_regions; i++)
+		iounmap(vdev->regions[i].ioaddr);
+
 	vdev->num_regions = 0;
 	kfree(vdev->regions);
 }
@@ -306,13 +315,115 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
 static ssize_t vfio_fsl_mc_read(void *device_data, char __user *buf,
 				size_t count, loff_t *ppos)
 {
-	return -EINVAL;
+	struct vfio_fsl_mc_device *vdev = device_data;
+	unsigned int index = VFIO_FSL_MC_OFFSET_TO_INDEX(*ppos);
+	loff_t off = *ppos & VFIO_FSL_MC_OFFSET_MASK;
+	struct vfio_fsl_mc_region *region;
+	u64 data[8];
+	int i;
+
+	if (index >= vdev->num_regions)
+		return -EINVAL;
+
+	region = &vdev->regions[index];
+
+	if (!(region->flags & VFIO_REGION_INFO_FLAG_READ))
+		return -EINVAL;
+
+	if (!region->ioaddr) {
+		region->ioaddr = ioremap(region->addr, region->size);
+		if (!region->ioaddr)
+			return -ENOMEM;
+	}
+
+	if (count != 64 || off != 0)
+		return -EINVAL;
+
+	for (i = 7; i >= 0; i--)
+		data[i] = readq(region->ioaddr + i * sizeof(uint64_t));
+
+	if (copy_to_user(buf, data, 64))
+		return -EFAULT;
+
+	return count;
+}
+
+#define MC_CMD_COMPLETION_TIMEOUT_MS    5000
+#define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS    500
+
+static int vfio_fsl_mc_send_command(void __iomem *ioaddr, uint64_t *cmd_data)
+{
+	int i;
+	enum mc_cmd_status status;
+	unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000;
+
+	/* Write at command parameter into portal */
+	for (i = 7; i >= 1; i--)
+		writeq_relaxed(cmd_data[i], ioaddr + i * sizeof(uint64_t));
+
+	/* Write command header in the end */
+	writeq(cmd_data[0], ioaddr);
+
+	/* Wait for response before returning to user-space
+	 * This can be optimized in future to even prepare response
+	 * before returning to user-space and avoid read ioctl.
+	 */
+	for (;;) {
+		u64 header;
+		struct mc_cmd_header *resp_hdr;
+
+		header = cpu_to_le64(readq_relaxed(ioaddr));
+
+		resp_hdr = (struct mc_cmd_header *)&header;
+		status = (enum mc_cmd_status)resp_hdr->status;
+		if (status != MC_CMD_STATUS_READY)
+			break;
+
+		udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
+		timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS;
+		if (timeout_usecs == 0)
+			return -ETIMEDOUT;
+	}
+
+	return 0;
 }
 
 static ssize_t vfio_fsl_mc_write(void *device_data, const char __user *buf,
 				 size_t count, loff_t *ppos)
 {
-	return -EINVAL;
+	struct vfio_fsl_mc_device *vdev = device_data;
+	unsigned int index = VFIO_FSL_MC_OFFSET_TO_INDEX(*ppos);
+	loff_t off = *ppos & VFIO_FSL_MC_OFFSET_MASK;
+	struct vfio_fsl_mc_region *region;
+	u64 data[8];
+	int ret;
+
+	if (index >= vdev->num_regions)
+		return -EINVAL;
+
+	region = &vdev->regions[index];
+
+	if (!(region->flags & VFIO_REGION_INFO_FLAG_WRITE))
+		return -EINVAL;
+
+	if (!region->ioaddr) {
+		region->ioaddr = ioremap(region->addr, region->size);
+		if (!region->ioaddr)
+			return -ENOMEM;
+	}
+
+	if (count != 64 || off != 0)
+		return -EINVAL;
+
+	if (copy_from_user(&data, buf, 64))
+		return -EFAULT;
+
+	ret = vfio_fsl_mc_send_command(region->ioaddr, data);
+	if (ret)
+		return ret;
+
+	return count;
+
 }
 
 static int vfio_fsl_mc_mmap_mmio(struct vfio_fsl_mc_region region,
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index 1f9b518c520d..c407d36b80b5 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -32,6 +32,7 @@ struct vfio_fsl_mc_region {
 	u32			type;
 	u64			addr;
 	resource_size_t		size;
+	void __iomem		*ioaddr;
 };
 
 struct vfio_fsl_mc_device {
-- 
2.17.1

Re: [PATCH v3 2/9] vfio/fsl-mc: Scan DPRC objects on vfio-fsl-mc driver bind

[Alex Williamson]

On Mon,  6 Jul 2020 18:41:46 +0300
Diana Craciun <diana.craciun@oss.nxp.com> wrote:

> The DPRC (Data Path Resource Container) device is a bus device and has
> child devices attached to it. When the vfio-fsl-mc driver is probed
> the DPRC is scanned and the child devices discovered and initialized.
> 
> Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
> Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
> ---
>  drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 106 ++++++++++++++++++++++
>  drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |   1 +
>  2 files changed, 107 insertions(+)
> 
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> index 8b53c2a25b32..ad8d06cceb71 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> @@ -15,6 +15,8 @@
>  
>  #include "vfio_fsl_mc_private.h"
>  
> +static struct fsl_mc_driver vfio_fsl_mc_driver;
> +
>  static int vfio_fsl_mc_open(void *device_data)
>  {
>  	if (!try_module_get(THIS_MODULE))
> @@ -84,6 +86,69 @@ static const struct vfio_device_ops vfio_fsl_mc_ops = {
>  	.mmap		= vfio_fsl_mc_mmap,
>  };
>  
> +static int vfio_fsl_mc_bus_notifier(struct notifier_block *nb,
> +				    unsigned long action, void *data)
> +{
> +	struct vfio_fsl_mc_device *vdev = container_of(nb,
> +					struct vfio_fsl_mc_device, nb);
> +	struct device *dev = data;
> +	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
> +	struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);
> +
> +	if (action == BUS_NOTIFY_ADD_DEVICE &&
> +	    vdev->mc_dev == mc_cont) {
> +		mc_dev->driver_override = kasprintf(GFP_KERNEL, "%s",
> +						    vfio_fsl_mc_ops.name);

I notice the vfio-pci code that this is modeled from also doesn't check
this allocation for NULL.  Maybe both should print a dev_warn on the
ultra slim chance it would fail.

> +		dev_info(dev, "Setting driver override for device in dprc %s\n",
> +			 dev_name(&mc_cont->dev));
> +	} else if (action == BUS_NOTIFY_BOUND_DRIVER &&
> +		vdev->mc_dev == mc_cont) {
> +		struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver);
> +
> +		if (mc_drv && mc_drv != &vfio_fsl_mc_driver)
> +			dev_warn(dev, "Object %s bound to driver %s while DPRC bound to vfio-fsl-mc\n",
> +				 dev_name(dev), mc_drv->driver.name);
> +		}

Nit, } is over-indented, should be aligned to the previous 'else if'.

> +
> +	return 0;
> +}
> +
> +static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
> +{
> +	struct fsl_mc_device *mc_dev = vdev->mc_dev;
> +	int ret;
> +
> +	/* Non-dprc devices share mc_io from parent */
> +	if (!is_fsl_mc_bus_dprc(mc_dev)) {
> +		struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);
> +
> +		mc_dev->mc_io = mc_cont->mc_io;
> +		return 0;
> +	}
> +
> +	vdev->nb.notifier_call = vfio_fsl_mc_bus_notifier;
> +	ret = bus_register_notifier(&fsl_mc_bus_type, &vdev->nb);
> +	if (ret)
> +		return ret;
> +
> +	/* open DPRC, allocate a MC portal */
> +	ret = dprc_setup(mc_dev);
> +	if (ret < 0) {
> +		dev_err(&mc_dev->dev, "Failed to setup DPRC (error = %d)\n", ret);
> +		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
> +		return ret;
> +	}
> +
> +	ret = dprc_scan_container(mc_dev, false);
> +	if (ret < 0) {
> +		dev_err(&mc_dev->dev, "Container scanning failed: %d\n", ret);
> +		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
> +		dprc_cleanup(mc_dev);

All else being equal, should these be reversed to mirror the setup?

> +	}
> +
> +	return ret;
> +}
> +
>  static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
>  {
>  	struct iommu_group *group;
> @@ -112,9 +177,42 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
>  		return ret;
>  	}
>  
> +	ret = vfio_fsl_mc_init_device(vdev);
> +	if (ret < 0) {
> +		vfio_iommu_group_put(group, dev);
> +		return ret;
> +	}
> +
>  	return ret;
>  }
>  
> +static int vfio_fsl_mc_device_remove(struct device *dev, void *data)
> +{
> +	struct fsl_mc_device *mc_dev;
> +
> +	WARN_ON(!dev);
> +	mc_dev = to_fsl_mc_device(dev);
> +	if (WARN_ON(!mc_dev))
> +		return -ENODEV;
> +
> +	kfree(mc_dev->driver_override);
> +	mc_dev->driver_override = NULL;

This is out of scope, all other buses that support a driver_override
free this is the bus driver code.  Why isn't it sufficient that it's
done in fsl_mc_device_remove()?

> +
> +	/*
> +	 * The device-specific remove callback will get invoked by device_del()
> +	 */
> +	device_del(&mc_dev->dev);
> +	put_device(&mc_dev->dev);

In fact, why are we doing any of this?  I think these devices were
created via dprc_scan_container(), so shouldn't there be a dprc
callback to remove them?  What happens if one of them did get bound to
another driver, haven't we just deleted the device out from under them?
In vfio-pci for instance, we call pci_disable_sriov() to remove any
vfs.  Thanks,

Alex

> +
> +	return 0;
> +}
> +
> +static void vfio_fsl_mc_cleanup_dprc(struct fsl_mc_device *mc_dev)
> +{
> +	device_for_each_child(&mc_dev->dev, NULL, vfio_fsl_mc_device_remove);
> +	dprc_cleanup(mc_dev);
> +}
> +
>  static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
>  {
>  	struct vfio_fsl_mc_device *vdev;
> @@ -124,6 +222,14 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
>  	if (!vdev)
>  		return -EINVAL;
>  
> +	if (vdev->nb.notifier_call)
> +		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
> +
> +	if (is_fsl_mc_bus_dprc(mc_dev))
> +		vfio_fsl_mc_cleanup_dprc(vdev->mc_dev);
> +
> +	mc_dev->mc_io = NULL;
> +
>  	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
>  
>  	return 0;
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> index e79cc116f6b8..37d61eaa58c8 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> @@ -9,6 +9,7 @@
>  
>  struct vfio_fsl_mc_device {
>  	struct fsl_mc_device		*mc_dev;
> +	struct notifier_block        nb;
>  };
>  
>  #endif /* VFIO_FSL_MC_PRIVATE_H */

Re: [PATCH v3 4/9] vfio/fsl-mc: Implement VFIO_DEVICE_GET_REGION_INFO ioctl call

[Alex Williamson]

On Mon,  6 Jul 2020 18:41:48 +0300
Diana Craciun <diana.craciun@oss.nxp.com> wrote:

> Expose to userspace information about the memory regions.
> 
> Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
> Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
> ---
>  drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 77 ++++++++++++++++++++++-
>  drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 19 ++++++
>  2 files changed, 95 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> index 937b6eddc71a..10bd9f78b8de 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
> @@ -17,16 +17,72 @@
>  
>  static struct fsl_mc_driver vfio_fsl_mc_driver;
>  
> +static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
> +{
> +	struct fsl_mc_device *mc_dev = vdev->mc_dev;
> +	int count = mc_dev->obj_desc.region_count;
> +	int i;
> +
> +	vdev->regions = kcalloc(count, sizeof(struct vfio_fsl_mc_region),
> +				GFP_KERNEL);
> +	if (!vdev->regions)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < count; i++) {
> +		struct resource *res = &mc_dev->regions[i];
> +
> +		vdev->regions[i].addr = res->start;
> +		vdev->regions[i].size = resource_size(res);
> +		vdev->regions[i].flags = 0;
> +	}
> +
> +	vdev->num_regions = mc_dev->obj_desc.region_count;
> +	return 0;
> +}
> +
> +static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev)
> +{
> +	vdev->num_regions = 0;
> +	kfree(vdev->regions);
> +}
> +
>  static int vfio_fsl_mc_open(void *device_data)
>  {
> +	struct vfio_fsl_mc_device *vdev = device_data;
> +	int ret;
> +
>  	if (!try_module_get(THIS_MODULE))
>  		return -ENODEV;
>  
> +	mutex_lock(&vdev->driver_lock);
> +	if (!vdev->refcnt) {
> +		ret = vfio_fsl_mc_regions_init(vdev);
> +		if (ret)
> +			goto err_reg_init;
> +	}
> +	vdev->refcnt++;
> +
> +	mutex_unlock(&vdev->driver_lock);
> +
>  	return 0;
> +
> +err_reg_init:
> +	mutex_unlock(&vdev->driver_lock);
> +	module_put(THIS_MODULE);
> +	return ret;
>  }
>  
>  static void vfio_fsl_mc_release(void *device_data)
>  {
> +	struct vfio_fsl_mc_device *vdev = device_data;
> +
> +	mutex_lock(&vdev->driver_lock);
> +
> +	if (!(--vdev->refcnt))
> +		vfio_fsl_mc_regions_cleanup(vdev);
> +
> +	mutex_unlock(&vdev->driver_lock);
> +
>  	module_put(THIS_MODULE);
>  }
>  
> @@ -59,7 +115,25 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
>  	}
>  	case VFIO_DEVICE_GET_REGION_INFO:
>  	{
> -		return -ENOTTY;
> +		struct vfio_region_info info;
> +
> +		minsz = offsetofend(struct vfio_region_info, offset);
> +
> +		if (copy_from_user(&info, (void __user *)arg, minsz))
> +			return -EFAULT;
> +
> +		if (info.argsz < minsz)
> +			return -EINVAL;
> +
> +		if (info.index >= vdev->num_regions)
> +			return -EINVAL;
> +
> +		/* map offset to the physical address  */
> +		info.offset = VFIO_FSL_MC_INDEX_TO_OFFSET(info.index);
> +		info.size = vdev->regions[info.index].size;
> +		info.flags = vdev->regions[info.index].flags;
> +
> +		return copy_to_user((void __user *)arg, &info, minsz);
>  	}
>  	case VFIO_DEVICE_GET_IRQ_INFO:
>  	{
> @@ -201,6 +275,7 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
>  		vfio_iommu_group_put(group, dev);
>  		return ret;
>  	}
> +	mutex_init(&vdev->driver_lock);


Consider all calling mutex_destory() in the remove callback, it's only
used for lock debugging, so we're only partially successful in calling
it.  Thanks,

Alex

>  
>  	return ret;
>  }
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> index 37d61eaa58c8..818dfd3df4db 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
> @@ -7,9 +7,28 @@
>  #ifndef VFIO_FSL_MC_PRIVATE_H
>  #define VFIO_FSL_MC_PRIVATE_H
>  
> +#define VFIO_FSL_MC_OFFSET_SHIFT    40
> +#define VFIO_FSL_MC_OFFSET_MASK (((u64)(1) << VFIO_FSL_MC_OFFSET_SHIFT) - 1)
> +
> +#define VFIO_FSL_MC_OFFSET_TO_INDEX(off) ((off) >> VFIO_FSL_MC_OFFSET_SHIFT)
> +
> +#define VFIO_FSL_MC_INDEX_TO_OFFSET(index)	\
> +	((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
> +
> +struct vfio_fsl_mc_region {
> +	u32			flags;
> +	u32			type;
> +	u64			addr;
> +	resource_size_t		size;
> +};
> +
>  struct vfio_fsl_mc_device {
>  	struct fsl_mc_device		*mc_dev;
>  	struct notifier_block        nb;
> +	int				refcnt;
> +	u32				num_regions;
> +	struct vfio_fsl_mc_region	*regions;
> +	struct mutex driver_lock;
>  };
>  
>  #endif /* VFIO_FSL_MC_PRIVATE_H */