* [PATCH 0/8] Introduce a device-dax bus-based device-model
@ 2018-10-31 3:12 Dan Williams
2018-10-31 3:12 ` [PATCH 1/8] device-dax: Kill dax_region ida Dan Williams
` (7 more replies)
0 siblings, 8 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:12 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
Prompted by the review of "[PATCH 0/9] Allow persistent memory to be
used like normal RAM" [1] introduce a new bus / device-driver-model
for device-dax.
Currently device-dax instances result from attaching an nvdimm namespace
device to the dax_pmem driver. These instances are registered with the
/sys/class/dax sub-system. With the expectation that platforms will
describe performance differentiated memory [2] for ranges other than
persistent memory (pmem) a new device-model is needed.
Arrange for dax_pmem to be one of potentially several drivers that know
how to discover differentiated memory and register a device instance on
the dax bus. The expectation is that, by default, this device is
consumed by the typical device-dax driver that will expose the range
through a /dev/daxX.Y character device. Optionally other drivers can
consume the dax device instance. For example, the kmem driver [1] can
attach to device-dax device instance to hot-add the related memory range
to the core page-allocator.
Going forward, provider drivers outside of dax_pmem can be created to
register other memories with unique performance properties.
Since /sys/class/dax is a released ABI, a compat driver is provided so
that distros can opt-in to the new bus based ABI. The /sys/class/dax
interface is then deprecated and scheduled to be removed.
[1]: https://lkml.org/lkml/2018/10/23/9
[2]: Section 5.2.27 Heterogeneous Memory Attribute Table (HMAT)
http://www.uefi.org/sites/default/files/resources/ACPI%206_2_A_Sept29.pdf
---
Dan Williams (8):
device-dax: Kill dax_region ida
device-dax: Kill dax_region base
device-dax: Remove multi-resource infrastructure
device-dax: Start defining a dax bus model
device-dax: Introduce bus + driver model
device-dax: Move resource pinning+mapping into the common driver
device-dax: Add support for a dax override driver
device-dax: Add /sys/class/dax backwards compatibility
Documentation/ABI/obsolete/sysfs-class-dax | 22 +
drivers/dax/Kconfig | 12 +
drivers/dax/Makefile | 5
drivers/dax/bus.c | 449 ++++++++++++++++++++++++++++
drivers/dax/bus.h | 60 ++++
drivers/dax/dax-private.h | 30 +-
drivers/dax/dax.h | 18 -
drivers/dax/device-dax.h | 25 --
drivers/dax/device.c | 365 +++++------------------
drivers/dax/pmem.c | 161 ----------
drivers/dax/pmem/Makefile | 7
drivers/dax/pmem/compat.c | 73 +++++
drivers/dax/pmem/core.c | 69 ++++
drivers/dax/pmem/pmem.c | 40 ++
drivers/dax/super.c | 41 ++-
tools/testing/nvdimm/Kbuild | 7
tools/testing/nvdimm/dax-dev.c | 16 -
17 files changed, 880 insertions(+), 520 deletions(-)
create mode 100644 Documentation/ABI/obsolete/sysfs-class-dax
create mode 100644 drivers/dax/bus.c
create mode 100644 drivers/dax/bus.h
delete mode 100644 drivers/dax/dax.h
delete mode 100644 drivers/dax/device-dax.h
delete mode 100644 drivers/dax/pmem.c
create mode 100644 drivers/dax/pmem/Makefile
create mode 100644 drivers/dax/pmem/compat.c
create mode 100644 drivers/dax/pmem/core.c
create mode 100644 drivers/dax/pmem/pmem.c
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH 1/8] device-dax: Kill dax_region ida
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
@ 2018-10-31 3:12 ` Dan Williams
2018-10-31 3:13 ` [PATCH 2/8] device-dax: Kill dax_region base Dan Williams
` (6 subsequent siblings)
7 siblings, 0 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:12 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
Commit bbb3be170ac2 "device-dax: fix sysfs duplicate warnings" arranged
for passing a dax instance-id to devm_create_dax_dev(), rather than
generating one internally. Remove the dax_region ida and related code.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/dax-private.h | 3 ---
drivers/dax/device.c | 24 +++---------------------
2 files changed, 3 insertions(+), 24 deletions(-)
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index b6fc4f04636d..d1b36a42132f 100644
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -28,7 +28,6 @@
*/
struct dax_region {
int id;
- struct ida ida;
void *base;
struct kref kref;
struct device *dev;
@@ -42,7 +41,6 @@ struct dax_region {
* @region - parent region
* @dax_dev - core dax functionality
* @dev - device core
- * @id - child id in the region
* @num_resources - number of physical address extents in this device
* @res - array of physical address ranges
*/
@@ -50,7 +48,6 @@ struct dev_dax {
struct dax_region *region;
struct dax_device *dax_dev;
struct device dev;
- int id;
int num_resources;
struct resource res[0];
};
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 948806e57cee..a5a670c1cd58 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -128,7 +128,6 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id,
dax_region->pfn_flags = pfn_flags;
kref_init(&dax_region->kref);
dax_region->id = region_id;
- ida_init(&dax_region->ida);
dax_region->align = align;
dax_region->dev = parent;
dax_region->base = addr;
@@ -582,8 +581,6 @@ static void dev_dax_release(struct device *dev)
struct dax_region *dax_region = dev_dax->region;
struct dax_device *dax_dev = dev_dax->dax_dev;
- if (dev_dax->id >= 0)
- ida_simple_remove(&dax_region->ida, dev_dax->id);
dax_region_put(dax_region);
put_dax(dax_dev);
kfree(dev_dax);
@@ -642,19 +639,7 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
}
if (i < count)
- goto err_id;
-
- if (id < 0) {
- id = ida_simple_get(&dax_region->ida, 0, 0, GFP_KERNEL);
- dev_dax->id = id;
- if (id < 0) {
- rc = id;
- goto err_id;
- }
- } else {
- /* region provider owns @id lifetime */
- dev_dax->id = -1;
- }
+ goto err;
/*
* No 'host' or dax_operations since there is no access to this
@@ -663,7 +648,7 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
dax_dev = alloc_dax(dev_dax, NULL, NULL);
if (!dax_dev) {
rc = -ENOMEM;
- goto err_dax;
+ goto err;
}
/* from here on we're committed to teardown via dax_dev_release() */
@@ -700,10 +685,7 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
return dev_dax;
- err_dax:
- if (dev_dax->id >= 0)
- ida_simple_remove(&dax_region->ida, dev_dax->id);
- err_id:
+ err:
kfree(dev_dax);
return ERR_PTR(rc);
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 2/8] device-dax: Kill dax_region base
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
2018-10-31 3:12 ` [PATCH 1/8] device-dax: Kill dax_region ida Dan Williams
@ 2018-10-31 3:13 ` Dan Williams
2018-10-31 3:13 ` [PATCH 3/8] device-dax: Remove multi-resource infrastructure Dan Williams
` (5 subsequent siblings)
7 siblings, 0 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:13 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
Nothing consumes this attribute of a region and devres otherwise
remembers the value for de-allocation purposes.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/dax-private.h | 2 --
drivers/dax/device-dax.h | 5 ++---
drivers/dax/device.c | 3 +--
drivers/dax/pmem.c | 2 +-
4 files changed, 4 insertions(+), 8 deletions(-)
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index d1b36a42132f..9b393c218fe4 100644
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -19,7 +19,6 @@
/**
* struct dax_region - mapping infrastructure for dax devices
* @id: kernel-wide unique region for a memory range
- * @base: linear address corresponding to @res
* @kref: to pin while other agents have a need to do lookups
* @dev: parent device backing this region
* @align: allocation and mapping alignment for child dax devices
@@ -28,7 +27,6 @@
*/
struct dax_region {
int id;
- void *base;
struct kref kref;
struct device *dev;
unsigned int align;
diff --git a/drivers/dax/device-dax.h b/drivers/dax/device-dax.h
index 688b051750bd..4f1c69e1b3a2 100644
--- a/drivers/dax/device-dax.h
+++ b/drivers/dax/device-dax.h
@@ -17,9 +17,8 @@ struct dev_dax;
struct resource;
struct dax_region;
void dax_region_put(struct dax_region *dax_region);
-struct dax_region *alloc_dax_region(struct device *parent,
- int region_id, struct resource *res, unsigned int align,
- void *addr, unsigned long flags);
+struct dax_region *alloc_dax_region(struct device *parent, int region_id,
+ struct resource *res, unsigned int align, unsigned long flags);
struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
int id, struct resource *res, int count);
#endif /* __DEVICE_DAX_H__ */
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index a5a670c1cd58..811c1015194c 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -100,7 +100,7 @@ static void dax_region_unregister(void *region)
}
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
- struct resource *res, unsigned int align, void *addr,
+ struct resource *res, unsigned int align,
unsigned long pfn_flags)
{
struct dax_region *dax_region;
@@ -130,7 +130,6 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id,
dax_region->id = region_id;
dax_region->align = align;
dax_region->dev = parent;
- dax_region->base = addr;
if (sysfs_create_groups(&parent->kobj, dax_region_attribute_groups)) {
kfree(dax_region);
return NULL;
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c
index 99e2aace8078..3afae503fc42 100644
--- a/drivers/dax/pmem.c
+++ b/drivers/dax/pmem.c
@@ -133,7 +133,7 @@ static int dax_pmem_probe(struct device *dev)
return -EINVAL;
dax_region = alloc_dax_region(dev, region_id, &res,
- le32_to_cpu(pfn_sb->align), addr, PFN_DEV|PFN_MAP);
+ le32_to_cpu(pfn_sb->align), PFN_DEV|PFN_MAP);
if (!dax_region)
return -ENOMEM;
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 3/8] device-dax: Remove multi-resource infrastructure
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
2018-10-31 3:12 ` [PATCH 1/8] device-dax: Kill dax_region ida Dan Williams
2018-10-31 3:13 ` [PATCH 2/8] device-dax: Kill dax_region base Dan Williams
@ 2018-10-31 3:13 ` Dan Williams
2018-10-31 3:13 ` [PATCH 4/8] device-dax: Start defining a dax bus model Dan Williams
` (4 subsequent siblings)
7 siblings, 0 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:13 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
The multi-resource implementation anticipated discontiguous sub-division
support. That has not yet materialized, delete the infrastructure and
related code.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/dax-private.h | 4 ---
drivers/dax/device-dax.h | 3 +-
drivers/dax/device.c | 49 +++++++---------------------------------
drivers/dax/pmem.c | 3 +-
tools/testing/nvdimm/dax-dev.c | 16 ++-----------
5 files changed, 13 insertions(+), 62 deletions(-)
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index 9b393c218fe4..dbd077653b5c 100644
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -39,14 +39,10 @@ struct dax_region {
* @region - parent region
* @dax_dev - core dax functionality
* @dev - device core
- * @num_resources - number of physical address extents in this device
- * @res - array of physical address ranges
*/
struct dev_dax {
struct dax_region *region;
struct dax_device *dax_dev;
struct device dev;
- int num_resources;
- struct resource res[0];
};
#endif
diff --git a/drivers/dax/device-dax.h b/drivers/dax/device-dax.h
index 4f1c69e1b3a2..e9be99584b92 100644
--- a/drivers/dax/device-dax.h
+++ b/drivers/dax/device-dax.h
@@ -19,6 +19,5 @@ struct dax_region;
void dax_region_put(struct dax_region *dax_region);
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct resource *res, unsigned int align, unsigned long flags);
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
- int id, struct resource *res, int count);
+struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id);
#endif /* __DEVICE_DAX_H__ */
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 811c1015194c..db12e24b8005 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -151,11 +151,7 @@ static ssize_t size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct dev_dax *dev_dax = to_dev_dax(dev);
- unsigned long long size = 0;
- int i;
-
- for (i = 0; i < dev_dax->num_resources; i++)
- size += resource_size(&dev_dax->res[i]);
+ unsigned long long size = resource_size(&dev_dax->region->res);
return sprintf(buf, "%llu\n", size);
}
@@ -224,21 +220,11 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
__weak phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff,
unsigned long size)
{
- struct resource *res;
- /* gcc-4.6.3-nolibc for i386 complains that this is uninitialized */
- phys_addr_t uninitialized_var(phys);
- int i;
-
- for (i = 0; i < dev_dax->num_resources; i++) {
- res = &dev_dax->res[i];
- phys = pgoff * PAGE_SIZE + res->start;
- if (phys >= res->start && phys <= res->end)
- break;
- pgoff -= PHYS_PFN(resource_size(res));
- }
+ struct resource *res = &dev_dax->region->res;
+ phys_addr_t phys;
- if (i < dev_dax->num_resources) {
- res = &dev_dax->res[i];
+ phys = pgoff * PAGE_SIZE + res->start;
+ if (phys >= res->start && phys <= res->end) {
if (phys + size - 1 <= res->end)
return phys;
}
@@ -608,8 +594,7 @@ static void unregister_dev_dax(void *dev)
put_device(dev);
}
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
- int id, struct resource *res, int count)
+struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id)
{
struct device *parent = dax_region->dev;
struct dax_device *dax_dev;
@@ -617,29 +602,12 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
struct inode *inode;
struct device *dev;
struct cdev *cdev;
- int rc, i;
+ int rc;
- if (!count)
- return ERR_PTR(-EINVAL);
-
- dev_dax = kzalloc(struct_size(dev_dax, res, count), GFP_KERNEL);
+ dev_dax = kzalloc(sizeof(*dev_dax), GFP_KERNEL);
if (!dev_dax)
return ERR_PTR(-ENOMEM);
- for (i = 0; i < count; i++) {
- if (!IS_ALIGNED(res[i].start, dax_region->align)
- || !IS_ALIGNED(resource_size(&res[i]),
- dax_region->align)) {
- rc = -EINVAL;
- break;
- }
- dev_dax->res[i].start = res[i].start;
- dev_dax->res[i].end = res[i].end;
- }
-
- if (i < count)
- goto err;
-
/*
* No 'host' or dax_operations since there is no access to this
* device outside of mmap of the resulting character device.
@@ -659,7 +627,6 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
cdev_init(cdev, &dax_fops);
cdev->owner = parent->driver->owner;
- dev_dax->num_resources = count;
dev_dax->dax_dev = dax_dev;
dev_dax->region = dax_region;
kref_get(&dax_region->kref);
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c
index 3afae503fc42..23bc8ed40e84 100644
--- a/drivers/dax/pmem.c
+++ b/drivers/dax/pmem.c
@@ -137,8 +137,7 @@ static int dax_pmem_probe(struct device *dev)
if (!dax_region)
return -ENOMEM;
- /* TODO: support for subdividing a dax region... */
- dev_dax = devm_create_dev_dax(dax_region, id, &res, 1);
+ dev_dax = devm_create_dev_dax(dax_region, id);
/* child dev_dax instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
diff --git a/tools/testing/nvdimm/dax-dev.c b/tools/testing/nvdimm/dax-dev.c
index 36ee3d8797c3..f36e708265b8 100644
--- a/tools/testing/nvdimm/dax-dev.c
+++ b/tools/testing/nvdimm/dax-dev.c
@@ -17,20 +17,11 @@
phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff,
unsigned long size)
{
- struct resource *res;
+ struct resource *res = &dev_dax->region->res;
phys_addr_t addr;
- int i;
- for (i = 0; i < dev_dax->num_resources; i++) {
- res = &dev_dax->res[i];
- addr = pgoff * PAGE_SIZE + res->start;
- if (addr >= res->start && addr <= res->end)
- break;
- pgoff -= PHYS_PFN(resource_size(res));
- }
-
- if (i < dev_dax->num_resources) {
- res = &dev_dax->res[i];
+ addr = pgoff * PAGE_SIZE + res->start;
+ if (addr >= res->start && addr <= res->end) {
if (addr + size - 1 <= res->end) {
if (get_nfit_res(addr)) {
struct page *page;
@@ -44,6 +35,5 @@ phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff,
return addr;
}
}
-
return -1;
}
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 4/8] device-dax: Start defining a dax bus model
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
` (2 preceding siblings ...)
2018-10-31 3:13 ` [PATCH 3/8] device-dax: Remove multi-resource infrastructure Dan Williams
@ 2018-10-31 3:13 ` Dan Williams
2018-10-31 3:13 ` [PATCH 5/8] device-dax: Introduce bus + driver model Dan Williams
` (3 subsequent siblings)
7 siblings, 0 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:13 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
Towards eliminating the dax_class, move the dax-device-attribute
enabling to a new bus.c file in the core. The amount of code
thrash of sub-sequent patches is reduced as no logic changes are made,
just pure code movement.
A temporary export of unregister_dex_dax() and dax_attribute_groups is
needed to preserve compilation, but those symbols become static again in
a follow-on patch.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/Makefile | 1
drivers/dax/bus.c | 174 ++++++++++++++++++++++++++++++++++++++++
drivers/dax/bus.h | 15 +++
drivers/dax/dax-private.h | 14 +++
drivers/dax/dax.h | 18 ----
drivers/dax/device-dax.h | 23 -----
drivers/dax/device.c | 185 +------------------------------------------
drivers/dax/pmem.c | 2
drivers/dax/super.c | 1
tools/testing/nvdimm/Kbuild | 1
10 files changed, 210 insertions(+), 224 deletions(-)
create mode 100644 drivers/dax/bus.c
create mode 100644 drivers/dax/bus.h
delete mode 100644 drivers/dax/dax.h
delete mode 100644 drivers/dax/device-dax.h
diff --git a/drivers/dax/Makefile b/drivers/dax/Makefile
index 574286fac87c..658e6b9b1d74 100644
--- a/drivers/dax/Makefile
+++ b/drivers/dax/Makefile
@@ -4,5 +4,6 @@ obj-$(CONFIG_DEV_DAX) += device_dax.o
obj-$(CONFIG_DEV_DAX_PMEM) += dax_pmem.o
dax-y := super.o
+dax-y += bus.o
dax_pmem-y := pmem.o
device_dax-y := device.o
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
new file mode 100644
index 000000000000..8a398e8e1956
--- /dev/null
+++ b/drivers/dax/bus.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2017-2018 Intel Corporation. All rights reserved. */
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/dax.h>
+#include "dax-private.h"
+#include "bus.h"
+
+/*
+ * Rely on the fact that drvdata is set before the attributes are
+ * registered, and that the attributes are unregistered before drvdata
+ * is cleared to assume that drvdata is always valid.
+ */
+static ssize_t id_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dax_region *dax_region = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", dax_region->id);
+}
+static DEVICE_ATTR_RO(id);
+
+static ssize_t region_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dax_region *dax_region = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%llu\n", (unsigned long long)
+ resource_size(&dax_region->res));
+}
+static struct device_attribute dev_attr_region_size = __ATTR(size, 0444,
+ region_size_show, NULL);
+
+static ssize_t align_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dax_region *dax_region = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", dax_region->align);
+}
+static DEVICE_ATTR_RO(align);
+
+static struct attribute *dax_region_attributes[] = {
+ &dev_attr_region_size.attr,
+ &dev_attr_align.attr,
+ &dev_attr_id.attr,
+ NULL,
+};
+
+static const struct attribute_group dax_region_attribute_group = {
+ .name = "dax_region",
+ .attrs = dax_region_attributes,
+};
+
+static const struct attribute_group *dax_region_attribute_groups[] = {
+ &dax_region_attribute_group,
+ NULL,
+};
+
+static void dax_region_free(struct kref *kref)
+{
+ struct dax_region *dax_region;
+
+ dax_region = container_of(kref, struct dax_region, kref);
+ kfree(dax_region);
+}
+
+void dax_region_put(struct dax_region *dax_region)
+{
+ kref_put(&dax_region->kref, dax_region_free);
+}
+EXPORT_SYMBOL_GPL(dax_region_put);
+
+static void dax_region_unregister(void *region)
+{
+ struct dax_region *dax_region = region;
+
+ sysfs_remove_groups(&dax_region->dev->kobj,
+ dax_region_attribute_groups);
+ dax_region_put(dax_region);
+}
+
+struct dax_region *alloc_dax_region(struct device *parent, int region_id,
+ struct resource *res, unsigned int align,
+ unsigned long pfn_flags)
+{
+ struct dax_region *dax_region;
+
+ /*
+ * The DAX core assumes that it can store its private data in
+ * parent->driver_data. This WARN is a reminder / safeguard for
+ * developers of device-dax drivers.
+ */
+ if (dev_get_drvdata(parent)) {
+ dev_WARN(parent, "dax core failed to setup private data\n");
+ return NULL;
+ }
+
+ if (!IS_ALIGNED(res->start, align)
+ || !IS_ALIGNED(resource_size(res), align))
+ return NULL;
+
+ dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL);
+ if (!dax_region)
+ return NULL;
+
+ dev_set_drvdata(parent, dax_region);
+ memcpy(&dax_region->res, res, sizeof(*res));
+ dax_region->pfn_flags = pfn_flags;
+ kref_init(&dax_region->kref);
+ dax_region->id = region_id;
+ dax_region->align = align;
+ dax_region->dev = parent;
+ if (sysfs_create_groups(&parent->kobj, dax_region_attribute_groups)) {
+ kfree(dax_region);
+ return NULL;
+ }
+
+ kref_get(&dax_region->kref);
+ if (devm_add_action_or_reset(parent, dax_region_unregister, dax_region))
+ return NULL;
+ return dax_region;
+}
+EXPORT_SYMBOL_GPL(alloc_dax_region);
+
+static ssize_t size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dev_dax *dev_dax = to_dev_dax(dev);
+ unsigned long long size = resource_size(&dev_dax->region->res);
+
+ return sprintf(buf, "%llu\n", size);
+}
+static DEVICE_ATTR_RO(size);
+
+static struct attribute *dev_dax_attributes[] = {
+ &dev_attr_size.attr,
+ NULL,
+};
+
+static const struct attribute_group dev_dax_attribute_group = {
+ .attrs = dev_dax_attributes,
+};
+
+const struct attribute_group *dax_attribute_groups[] = {
+ &dev_dax_attribute_group,
+ NULL,
+};
+EXPORT_SYMBOL_GPL(dax_attribute_groups);
+
+void kill_dev_dax(struct dev_dax *dev_dax)
+{
+ struct dax_device *dax_dev = dev_dax->dax_dev;
+ struct inode *inode = dax_inode(dax_dev);
+
+ kill_dax(dax_dev);
+ unmap_mapping_range(inode->i_mapping, 0, 0, 1);
+}
+EXPORT_SYMBOL_GPL(kill_dev_dax);
+
+void unregister_dev_dax(void *dev)
+{
+ struct dev_dax *dev_dax = to_dev_dax(dev);
+ struct dax_device *dax_dev = dev_dax->dax_dev;
+ struct inode *inode = dax_inode(dax_dev);
+ struct cdev *cdev = inode->i_cdev;
+
+ dev_dbg(dev, "trace\n");
+
+ kill_dev_dax(dev_dax);
+ cdev_device_del(cdev, dev);
+ put_device(dev);
+}
+EXPORT_SYMBOL_GPL(unregister_dev_dax);
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h
new file mode 100644
index 000000000000..840865aa69e8
--- /dev/null
+++ b/drivers/dax/bus.h
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
+#ifndef __DAX_BUS_H__
+#define __DAX_BUS_H__
+struct device;
+struct dev_dax;
+struct resource;
+struct dax_device;
+struct dax_region;
+void dax_region_put(struct dax_region *dax_region);
+struct dax_region *alloc_dax_region(struct device *parent, int region_id,
+ struct resource *res, unsigned int align, unsigned long flags);
+struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id);
+void kill_dev_dax(struct dev_dax *dev_dax);
+#endif /* __DAX_BUS_H__ */
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index dbd077653b5c..620c3f4eefe7 100644
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -16,6 +16,15 @@
#include <linux/device.h>
#include <linux/cdev.h>
+/* private routines between core files */
+struct dax_device;
+struct dax_device *inode_dax(struct inode *inode);
+struct inode *dax_inode(struct dax_device *dax_dev);
+
+/* temporary until devm_create_dax_dev moves to bus.c */
+extern const struct attribute_group *dax_attribute_groups[];
+void unregister_dev_dax(void *dev);
+
/**
* struct dax_region - mapping infrastructure for dax devices
* @id: kernel-wide unique region for a memory range
@@ -45,4 +54,9 @@ struct dev_dax {
struct dax_device *dax_dev;
struct device dev;
};
+
+static inline struct dev_dax *to_dev_dax(struct device *dev)
+{
+ return container_of(dev, struct dev_dax, dev);
+}
#endif
diff --git a/drivers/dax/dax.h b/drivers/dax/dax.h
deleted file mode 100644
index f9e5feea742c..000000000000
--- a/drivers/dax/dax.h
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
- * Copyright(c) 2016 - 2017 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
-#ifndef __DAX_H__
-#define __DAX_H__
-struct dax_device;
-struct dax_device *inode_dax(struct inode *inode);
-struct inode *dax_inode(struct dax_device *dax_dev);
-#endif /* __DAX_H__ */
diff --git a/drivers/dax/device-dax.h b/drivers/dax/device-dax.h
deleted file mode 100644
index e9be99584b92..000000000000
--- a/drivers/dax/device-dax.h
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
- * Copyright(c) 2016 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
-#ifndef __DEVICE_DAX_H__
-#define __DEVICE_DAX_H__
-struct device;
-struct dev_dax;
-struct resource;
-struct dax_region;
-void dax_region_put(struct dax_region *dax_region);
-struct dax_region *alloc_dax_region(struct device *parent, int region_id,
- struct resource *res, unsigned int align, unsigned long flags);
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id);
-#endif /* __DEVICE_DAX_H__ */
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index db12e24b8005..1fc375783e0b 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -1,15 +1,5 @@
-/*
- * Copyright(c) 2016 - 2017 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2016-2018 Intel Corporation. All rights reserved. */
#include <linux/pagemap.h>
#include <linux/module.h>
#include <linux/device.h>
@@ -21,156 +11,10 @@
#include <linux/mm.h>
#include <linux/mman.h>
#include "dax-private.h"
-#include "dax.h"
+#include "bus.h"
static struct class *dax_class;
-/*
- * Rely on the fact that drvdata is set before the attributes are
- * registered, and that the attributes are unregistered before drvdata
- * is cleared to assume that drvdata is always valid.
- */
-static ssize_t id_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct dax_region *dax_region = dev_get_drvdata(dev);
-
- return sprintf(buf, "%d\n", dax_region->id);
-}
-static DEVICE_ATTR_RO(id);
-
-static ssize_t region_size_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct dax_region *dax_region = dev_get_drvdata(dev);
-
- return sprintf(buf, "%llu\n", (unsigned long long)
- resource_size(&dax_region->res));
-}
-static struct device_attribute dev_attr_region_size = __ATTR(size, 0444,
- region_size_show, NULL);
-
-static ssize_t align_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct dax_region *dax_region = dev_get_drvdata(dev);
-
- return sprintf(buf, "%u\n", dax_region->align);
-}
-static DEVICE_ATTR_RO(align);
-
-static struct attribute *dax_region_attributes[] = {
- &dev_attr_region_size.attr,
- &dev_attr_align.attr,
- &dev_attr_id.attr,
- NULL,
-};
-
-static const struct attribute_group dax_region_attribute_group = {
- .name = "dax_region",
- .attrs = dax_region_attributes,
-};
-
-static const struct attribute_group *dax_region_attribute_groups[] = {
- &dax_region_attribute_group,
- NULL,
-};
-
-static void dax_region_free(struct kref *kref)
-{
- struct dax_region *dax_region;
-
- dax_region = container_of(kref, struct dax_region, kref);
- kfree(dax_region);
-}
-
-void dax_region_put(struct dax_region *dax_region)
-{
- kref_put(&dax_region->kref, dax_region_free);
-}
-EXPORT_SYMBOL_GPL(dax_region_put);
-
-static void dax_region_unregister(void *region)
-{
- struct dax_region *dax_region = region;
-
- sysfs_remove_groups(&dax_region->dev->kobj,
- dax_region_attribute_groups);
- dax_region_put(dax_region);
-}
-
-struct dax_region *alloc_dax_region(struct device *parent, int region_id,
- struct resource *res, unsigned int align,
- unsigned long pfn_flags)
-{
- struct dax_region *dax_region;
-
- /*
- * The DAX core assumes that it can store its private data in
- * parent->driver_data. This WARN is a reminder / safeguard for
- * developers of device-dax drivers.
- */
- if (dev_get_drvdata(parent)) {
- dev_WARN(parent, "dax core failed to setup private data\n");
- return NULL;
- }
-
- if (!IS_ALIGNED(res->start, align)
- || !IS_ALIGNED(resource_size(res), align))
- return NULL;
-
- dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL);
- if (!dax_region)
- return NULL;
-
- dev_set_drvdata(parent, dax_region);
- memcpy(&dax_region->res, res, sizeof(*res));
- dax_region->pfn_flags = pfn_flags;
- kref_init(&dax_region->kref);
- dax_region->id = region_id;
- dax_region->align = align;
- dax_region->dev = parent;
- if (sysfs_create_groups(&parent->kobj, dax_region_attribute_groups)) {
- kfree(dax_region);
- return NULL;
- }
-
- kref_get(&dax_region->kref);
- if (devm_add_action_or_reset(parent, dax_region_unregister, dax_region))
- return NULL;
- return dax_region;
-}
-EXPORT_SYMBOL_GPL(alloc_dax_region);
-
-static struct dev_dax *to_dev_dax(struct device *dev)
-{
- return container_of(dev, struct dev_dax, dev);
-}
-
-static ssize_t size_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct dev_dax *dev_dax = to_dev_dax(dev);
- unsigned long long size = resource_size(&dev_dax->region->res);
-
- return sprintf(buf, "%llu\n", size);
-}
-static DEVICE_ATTR_RO(size);
-
-static struct attribute *dev_dax_attributes[] = {
- &dev_attr_size.attr,
- NULL,
-};
-
-static const struct attribute_group dev_dax_attribute_group = {
- .attrs = dev_dax_attributes,
-};
-
-static const struct attribute_group *dax_attribute_groups[] = {
- &dev_dax_attribute_group,
- NULL,
-};
-
static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
const char *func)
{
@@ -571,29 +415,6 @@ static void dev_dax_release(struct device *dev)
kfree(dev_dax);
}
-static void kill_dev_dax(struct dev_dax *dev_dax)
-{
- struct dax_device *dax_dev = dev_dax->dax_dev;
- struct inode *inode = dax_inode(dax_dev);
-
- kill_dax(dax_dev);
- unmap_mapping_range(inode->i_mapping, 0, 0, 1);
-}
-
-static void unregister_dev_dax(void *dev)
-{
- struct dev_dax *dev_dax = to_dev_dax(dev);
- struct dax_device *dax_dev = dev_dax->dax_dev;
- struct inode *inode = dax_inode(dax_dev);
- struct cdev *cdev = inode->i_cdev;
-
- dev_dbg(dev, "trace\n");
-
- kill_dev_dax(dev_dax);
- cdev_device_del(cdev, dev);
- put_device(dev);
-}
-
struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id)
{
struct device *parent = dax_region->dev;
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c
index 23bc8ed40e84..c94f17e662bd 100644
--- a/drivers/dax/pmem.c
+++ b/drivers/dax/pmem.c
@@ -16,7 +16,7 @@
#include <linux/pfn_t.h>
#include "../nvdimm/pfn.h"
#include "../nvdimm/nd.h"
-#include "device-dax.h"
+#include "bus.h"
struct dax_pmem {
struct device *dev;
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 6e928f37d084..0ecc1a2cf1cc 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -22,6 +22,7 @@
#include <linux/uio.h>
#include <linux/dax.h>
#include <linux/fs.h>
+#include "dax-private.h"
static dev_t dax_devt;
DEFINE_STATIC_SRCU(dax_srcu);
diff --git a/tools/testing/nvdimm/Kbuild b/tools/testing/nvdimm/Kbuild
index 0392153a0009..bfc4d8e98452 100644
--- a/tools/testing/nvdimm/Kbuild
+++ b/tools/testing/nvdimm/Kbuild
@@ -55,6 +55,7 @@ nd_e820-y := $(NVDIMM_SRC)/e820.o
nd_e820-y += config_check.o
dax-y := $(DAX_SRC)/super.o
+dax-y += $(DAX_SRC)/bus.o
dax-y += config_check.o
device_dax-y := $(DAX_SRC)/device.o
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 5/8] device-dax: Introduce bus + driver model
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
` (3 preceding siblings ...)
2018-10-31 3:13 ` [PATCH 4/8] device-dax: Start defining a dax bus model Dan Williams
@ 2018-10-31 3:13 ` Dan Williams
2018-10-31 3:13 ` [PATCH 6/8] device-dax: Move resource pinning+mapping into the common driver Dan Williams
` (2 subsequent siblings)
7 siblings, 0 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:13 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
In support of multiple device-dax instances per device-dax-region and
allowing the 'kmem' driver to attach to dax-instances instead of the
current device-node access, convert the dax sub-system from a class to a
bus. Recall that the kmem driver takes reserved / special purpose
memories and assigns them to be managed by the core-mm.
Aside from the fact the device-dax instances are registered and probed
on a bus, two other lifetime-management changes are made:
1/ Delay attaching a cdev until driver probe time
2/ A new run_dax() helper is introduced to allow restoring dax-operation
after a kill_dax() event. So, at driver ->probe() time we run_dax()
and at ->remove() time we kill_dax() and invalidate all mappings.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/bus.c | 133 ++++++++++++++++++++++++++++++++++++++++++---
drivers/dax/bus.h | 16 +++++
drivers/dax/dax-private.h | 6 +-
drivers/dax/device.c | 95 +++++++++++---------------------
drivers/dax/super.c | 40 +++++++++-----
5 files changed, 203 insertions(+), 87 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 8a398e8e1956..0cff32102c4c 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -6,6 +6,33 @@
#include "dax-private.h"
#include "bus.h"
+static int dax_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ /*
+ * We only ever expect to handle device-dax instances, i.e. the
+ * @type argument to MODULE_ALIAS_DAX_DEVICE() is always zero
+ */
+ return add_uevent_var(env, "MODALIAS=" DAX_DEVICE_MODALIAS_FMT, 0);
+}
+
+static int dax_bus_match(struct device *dev, struct device_driver *drv);
+
+static struct bus_type dax_bus_type = {
+ .name = "dax",
+ .uevent = dax_bus_uevent,
+ .match = dax_bus_match,
+};
+
+static int dax_bus_match(struct device *dev, struct device_driver *drv)
+{
+ /*
+ * The drivers that can register on the 'dax' bus are private to
+ * drivers/dax/ so any device and driver on the bus always
+ * match.
+ */
+ return 1;
+}
+
/*
* Rely on the fact that drvdata is set before the attributes are
* registered, and that the attributes are unregistered before drvdata
@@ -142,11 +169,10 @@ static const struct attribute_group dev_dax_attribute_group = {
.attrs = dev_dax_attributes,
};
-const struct attribute_group *dax_attribute_groups[] = {
+static const struct attribute_group *dax_attribute_groups[] = {
&dev_dax_attribute_group,
NULL,
};
-EXPORT_SYMBOL_GPL(dax_attribute_groups);
void kill_dev_dax(struct dev_dax *dev_dax)
{
@@ -158,17 +184,108 @@ void kill_dev_dax(struct dev_dax *dev_dax)
}
EXPORT_SYMBOL_GPL(kill_dev_dax);
-void unregister_dev_dax(void *dev)
+static void dev_dax_release(struct device *dev)
{
struct dev_dax *dev_dax = to_dev_dax(dev);
+ struct dax_region *dax_region = dev_dax->region;
struct dax_device *dax_dev = dev_dax->dax_dev;
- struct inode *inode = dax_inode(dax_dev);
- struct cdev *cdev = inode->i_cdev;
- dev_dbg(dev, "trace\n");
+ dax_region_put(dax_region);
+ put_dax(dax_dev);
+ kfree(dev_dax);
+}
+
+static void unregister_dev_dax(void *dev)
+{
+ struct dev_dax *dev_dax = to_dev_dax(dev);
+
+ dev_dbg(dev, "%s\n", __func__);
kill_dev_dax(dev_dax);
- cdev_device_del(cdev, dev);
+ device_del(dev);
put_device(dev);
}
-EXPORT_SYMBOL_GPL(unregister_dev_dax);
+
+struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id)
+{
+ struct device *parent = dax_region->dev;
+ struct dax_device *dax_dev;
+ struct dev_dax *dev_dax;
+ struct inode *inode;
+ struct device *dev;
+ int rc = -ENOMEM;
+
+ if (id < 0)
+ return ERR_PTR(-EINVAL);
+
+ dev_dax = kzalloc(sizeof(*dev_dax), GFP_KERNEL);
+ if (!dev_dax)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * No 'host' or dax_operations since there is no access to this
+ * device outside of mmap of the resulting character device.
+ */
+ dax_dev = alloc_dax(dev_dax, NULL, NULL);
+ if (!dax_dev)
+ goto err;
+
+ /* a device_dax instance is dead while the driver is not attached */
+ kill_dax(dax_dev);
+
+ /* from here on we're committed to teardown via dax_dev_release() */
+ dev = &dev_dax->dev;
+ device_initialize(dev);
+
+ dev_dax->dax_dev = dax_dev;
+ dev_dax->region = dax_region;
+ kref_get(&dax_region->kref);
+
+ inode = dax_inode(dax_dev);
+ dev->devt = inode->i_rdev;
+ dev->bus = &dax_bus_type;
+ dev->parent = parent;
+ dev->groups = dax_attribute_groups;
+ dev->release = dev_dax_release;
+ dev_set_name(dev, "dax%d.%d", dax_region->id, id);
+
+ rc = device_add(dev);
+ if (rc) {
+ kill_dev_dax(dev_dax);
+ put_device(dev);
+ return ERR_PTR(rc);
+ }
+
+ rc = devm_add_action_or_reset(dax_region->dev, unregister_dev_dax, dev);
+ if (rc)
+ return ERR_PTR(rc);
+
+ return dev_dax;
+
+ err:
+ kfree(dev_dax);
+
+ return ERR_PTR(rc);
+}
+EXPORT_SYMBOL_GPL(devm_create_dev_dax);
+
+int __dax_driver_register(struct device_driver *drv,
+ struct module *module, const char *mod_name)
+{
+ drv->owner = module;
+ drv->name = mod_name;
+ drv->mod_name = mod_name;
+ drv->bus = &dax_bus_type;
+ return driver_register(drv);
+}
+EXPORT_SYMBOL_GPL(__dax_driver_register);
+
+int __init dax_bus_init(void)
+{
+ return bus_register(&dax_bus_type);
+}
+
+void __exit dax_bus_exit(void)
+{
+ bus_unregister(&dax_bus_type);
+}
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h
index 840865aa69e8..ea509504df3a 100644
--- a/drivers/dax/bus.h
+++ b/drivers/dax/bus.h
@@ -11,5 +11,21 @@ void dax_region_put(struct dax_region *dax_region);
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct resource *res, unsigned int align, unsigned long flags);
struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id);
+int __dax_driver_register(struct device_driver *drv,
+ struct module *module, const char *mod_name);
+#define dax_driver_register(driver) \
+ __dax_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
void kill_dev_dax(struct dev_dax *dev_dax);
+
+/*
+ * While run_dax() is potentially a generic operation that could be
+ * defined in include/linux/dax.h we don't want to grow any users
+ * outside of drivers/dax/
+ */
+void run_dax(struct dax_device *dax_dev);
+
+#define MODULE_ALIAS_DAX_DEVICE(type) \
+ MODULE_ALIAS("dax:t" __stringify(type) "*")
+#define DAX_DEVICE_MODALIAS_FMT "dax:t%d"
+
#endif /* __DAX_BUS_H__ */
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index 620c3f4eefe7..c3a121700837 100644
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -20,10 +20,8 @@
struct dax_device;
struct dax_device *inode_dax(struct inode *inode);
struct inode *dax_inode(struct dax_device *dax_dev);
-
-/* temporary until devm_create_dax_dev moves to bus.c */
-extern const struct attribute_group *dax_attribute_groups[];
-void unregister_dev_dax(void *dev);
+int dax_bus_init(void);
+void dax_bus_exit(void);
/**
* struct dax_region - mapping infrastructure for dax devices
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 1fc375783e0b..f55829404a24 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -13,8 +13,6 @@
#include "dax-private.h"
#include "bus.h"
-static struct class *dax_class;
-
static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
const char *func)
{
@@ -404,93 +402,64 @@ static const struct file_operations dax_fops = {
.mmap_supported_flags = MAP_SYNC,
};
-static void dev_dax_release(struct device *dev)
+static void dev_dax_cdev_del(void *cdev)
{
- struct dev_dax *dev_dax = to_dev_dax(dev);
- struct dax_region *dax_region = dev_dax->region;
- struct dax_device *dax_dev = dev_dax->dax_dev;
+ cdev_del(cdev);
+}
- dax_region_put(dax_region);
- put_dax(dax_dev);
- kfree(dev_dax);
+static void dev_dax_kill(void *dev_dax)
+{
+ kill_dev_dax(dev_dax);
}
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id)
+static int dev_dax_probe(struct device *dev)
{
- struct device *parent = dax_region->dev;
- struct dax_device *dax_dev;
- struct dev_dax *dev_dax;
+ struct dev_dax *dev_dax = to_dev_dax(dev);
+ struct dax_device *dax_dev = dev_dax->dax_dev;
struct inode *inode;
- struct device *dev;
struct cdev *cdev;
int rc;
- dev_dax = kzalloc(sizeof(*dev_dax), GFP_KERNEL);
- if (!dev_dax)
- return ERR_PTR(-ENOMEM);
-
- /*
- * No 'host' or dax_operations since there is no access to this
- * device outside of mmap of the resulting character device.
- */
- dax_dev = alloc_dax(dev_dax, NULL, NULL);
- if (!dax_dev) {
- rc = -ENOMEM;
- goto err;
- }
-
- /* from here on we're committed to teardown via dax_dev_release() */
- dev = &dev_dax->dev;
- device_initialize(dev);
-
inode = dax_inode(dax_dev);
cdev = inode->i_cdev;
cdev_init(cdev, &dax_fops);
- cdev->owner = parent->driver->owner;
-
- dev_dax->dax_dev = dax_dev;
- dev_dax->region = dax_region;
- kref_get(&dax_region->kref);
-
- dev->devt = inode->i_rdev;
- dev->class = dax_class;
- dev->parent = parent;
- dev->groups = dax_attribute_groups;
- dev->release = dev_dax_release;
- dev_set_name(dev, "dax%d.%d", dax_region->id, id);
-
- rc = cdev_device_add(cdev, dev);
- if (rc) {
- kill_dev_dax(dev_dax);
- put_device(dev);
- return ERR_PTR(rc);
- }
-
- rc = devm_add_action_or_reset(dax_region->dev, unregister_dev_dax, dev);
+ cdev->owner = dev->driver->owner;
+ cdev_set_parent(cdev, &dev->kobj);
+ rc = cdev_add(cdev, dev->devt, 1);
if (rc)
- return ERR_PTR(rc);
+ return rc;
- return dev_dax;
+ rc = devm_add_action_or_reset(dev, dev_dax_cdev_del, cdev);
+ if (rc)
+ return rc;
- err:
- kfree(dev_dax);
+ run_dax(dax_dev);
+ return devm_add_action_or_reset(dev, dev_dax_kill, dev_dax);
+}
- return ERR_PTR(rc);
+static int dev_dax_remove(struct device *dev)
+{
+ /* all probe actions are unwound by devm */
+ return 0;
}
-EXPORT_SYMBOL_GPL(devm_create_dev_dax);
+
+static struct device_driver device_dax_driver = {
+ .probe = dev_dax_probe,
+ .remove = dev_dax_remove,
+};
static int __init dax_init(void)
{
- dax_class = class_create(THIS_MODULE, "dax");
- return PTR_ERR_OR_ZERO(dax_class);
+ return dax_driver_register(&device_dax_driver);
}
static void __exit dax_exit(void)
{
- class_destroy(dax_class);
+ driver_unregister(&device_dax_driver);
}
MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL v2");
-subsys_initcall(dax_init);
+module_init(dax_init);
module_exit(dax_exit);
+MODULE_ALIAS_DAX_DEVICE(0);
diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 0ecc1a2cf1cc..ccb22d8db3a2 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -366,11 +366,15 @@ void kill_dax(struct dax_device *dax_dev)
spin_lock(&dax_host_lock);
hlist_del_init(&dax_dev->list);
spin_unlock(&dax_host_lock);
-
- dax_dev->private = NULL;
}
EXPORT_SYMBOL_GPL(kill_dax);
+void run_dax(struct dax_device *dax_dev)
+{
+ set_bit(DAXDEV_ALIVE, &dax_dev->flags);
+}
+EXPORT_SYMBOL_GPL(run_dax);
+
static struct inode *dax_alloc_inode(struct super_block *sb)
{
struct dax_device *dax_dev;
@@ -585,6 +589,8 @@ EXPORT_SYMBOL_GPL(dax_inode);
void *dax_get_private(struct dax_device *dax_dev)
{
+ if (!test_bit(DAXDEV_ALIVE, &dax_dev->flags))
+ return NULL;
return dax_dev->private;
}
EXPORT_SYMBOL_GPL(dax_get_private);
@@ -598,7 +604,7 @@ static void init_once(void *_dax_dev)
inode_init_once(inode);
}
-static int __dax_fs_init(void)
+static int dax_fs_init(void)
{
int rc;
@@ -630,35 +636,45 @@ static int __dax_fs_init(void)
return rc;
}
-static void __dax_fs_exit(void)
+static void dax_fs_exit(void)
{
kern_unmount(dax_mnt);
unregister_filesystem(&dax_fs_type);
kmem_cache_destroy(dax_cache);
}
-static int __init dax_fs_init(void)
+static int __init dax_core_init(void)
{
int rc;
- rc = __dax_fs_init();
+ rc = dax_fs_init();
if (rc)
return rc;
rc = alloc_chrdev_region(&dax_devt, 0, MINORMASK+1, "dax");
if (rc)
- __dax_fs_exit();
- return rc;
+ goto err_chrdev;
+
+ rc = dax_bus_init();
+ if (rc)
+ goto err_bus;
+ return 0;
+
+err_bus:
+ unregister_chrdev_region(dax_devt, MINORMASK+1);
+err_chrdev:
+ dax_fs_exit();
+ return 0;
}
-static void __exit dax_fs_exit(void)
+static void __exit dax_core_exit(void)
{
unregister_chrdev_region(dax_devt, MINORMASK+1);
ida_destroy(&dax_minor_ida);
- __dax_fs_exit();
+ dax_fs_exit();
}
MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL v2");
-subsys_initcall(dax_fs_init);
-module_exit(dax_fs_exit);
+subsys_initcall(dax_core_init);
+module_exit(dax_core_exit);
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 6/8] device-dax: Move resource pinning+mapping into the common driver
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
` (4 preceding siblings ...)
2018-10-31 3:13 ` [PATCH 5/8] device-dax: Introduce bus + driver model Dan Williams
@ 2018-10-31 3:13 ` Dan Williams
2018-10-31 3:13 ` [PATCH 7/8] device-dax: Add support for a dax override driver Dan Williams
2018-10-31 3:13 ` [PATCH 8/8] device-dax: Add /sys/class/dax backwards compatibility Dan Williams
7 siblings, 0 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:13 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
Move the responsibility of calling devm_request_resource() and
devm_memremap_pages() into the common device-dax driver. This is another
preparatory step to allowing an alternate personality driver for a
device-dax range.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/bus.c | 6 ++-
drivers/dax/bus.h | 3 +
drivers/dax/dax-private.h | 9 ++++
drivers/dax/device.c | 65 ++++++++++++++++++++++++++++++
drivers/dax/pmem.c | 98 ++++++---------------------------------------
5 files changed, 94 insertions(+), 87 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 0cff32102c4c..69aae2cbd45f 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2017-2018 Intel Corporation. All rights reserved. */
+#include <linux/memremap.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/dax.h>
@@ -206,7 +207,8 @@ static void unregister_dev_dax(void *dev)
put_device(dev);
}
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id)
+struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
+ struct dev_pagemap *pgmap)
{
struct device *parent = dax_region->dev;
struct dax_device *dax_dev;
@@ -222,6 +224,8 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id)
if (!dev_dax)
return ERR_PTR(-ENOMEM);
+ memcpy(&dev_dax->pgmap, pgmap, sizeof(*pgmap));
+
/*
* No 'host' or dax_operations since there is no access to this
* device outside of mmap of the resulting character device.
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h
index ea509504df3a..e08e0c394983 100644
--- a/drivers/dax/bus.h
+++ b/drivers/dax/bus.h
@@ -10,7 +10,8 @@ struct dax_region;
void dax_region_put(struct dax_region *dax_region);
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct resource *res, unsigned int align, unsigned long flags);
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id);
+struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
+ struct dev_pagemap *pgmap);
int __dax_driver_register(struct device_driver *drv,
struct module *module, const char *mod_name);
#define dax_driver_register(driver) \
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index c3a121700837..a82ce48f5884 100644
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -42,15 +42,22 @@ struct dax_region {
};
/**
- * struct dev_dax - instance data for a subdivision of a dax region
+ * struct dev_dax - instance data for a subdivision of a dax region, and
+ * data while the device is activated in the driver.
* @region - parent region
* @dax_dev - core dax functionality
* @dev - device core
+ * @pgmap - pgmap for memmap setup / lifetime (driver owned)
+ * @ref: pgmap reference count (driver owned)
+ * @cmp: @ref final put completion (driver owned)
*/
struct dev_dax {
struct dax_region *region;
struct dax_device *dax_dev;
struct device dev;
+ struct dev_pagemap pgmap;
+ struct percpu_ref ref;
+ struct completion cmp;
};
static inline struct dev_dax *to_dev_dax(struct device *dev)
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index f55829404a24..967bab097013 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2016-2018 Intel Corporation. All rights reserved. */
+#include <linux/memremap.h>
#include <linux/pagemap.h>
#include <linux/module.h>
#include <linux/device.h>
@@ -13,6 +14,38 @@
#include "dax-private.h"
#include "bus.h"
+static struct dev_dax *ref_to_dev_dax(struct percpu_ref *ref)
+{
+ return container_of(ref, struct dev_dax, ref);
+}
+
+static void dev_dax_percpu_release(struct percpu_ref *ref)
+{
+ struct dev_dax *dev_dax = ref_to_dev_dax(ref);
+
+ dev_dbg(&dev_dax->dev, "%s\n", __func__);
+ complete(&dev_dax->cmp);
+}
+
+static void dev_dax_percpu_exit(void *data)
+{
+ struct percpu_ref *ref = data;
+ struct dev_dax *dev_dax = ref_to_dev_dax(ref);
+
+ dev_dbg(&dev_dax->dev, "%s\n", __func__);
+ wait_for_completion(&dev_dax->cmp);
+ percpu_ref_exit(ref);
+}
+
+static void dev_dax_percpu_kill(void *data)
+{
+ struct percpu_ref *ref = data;
+ struct dev_dax *dev_dax = ref_to_dev_dax(ref);
+
+ dev_dbg(&dev_dax->dev, "%s\n", __func__);
+ percpu_ref_kill(ref);
+}
+
static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
const char *func)
{
@@ -416,10 +449,42 @@ static int dev_dax_probe(struct device *dev)
{
struct dev_dax *dev_dax = to_dev_dax(dev);
struct dax_device *dax_dev = dev_dax->dax_dev;
+ struct resource *res = &dev_dax->region->res;
struct inode *inode;
struct cdev *cdev;
+ void *addr;
int rc;
+ /* 1:1 map region resource range to device-dax instance range */
+ if (!devm_request_mem_region(dev, res->start, resource_size(res),
+ dev_name(dev))) {
+ dev_warn(dev, "could not reserve region %pR\n", res);
+ return -EBUSY;
+ }
+
+ init_completion(&dev_dax->cmp);
+ rc = percpu_ref_init(&dev_dax->ref, dev_dax_percpu_release, 0,
+ GFP_KERNEL);
+ if (rc)
+ return rc;
+
+ rc = devm_add_action_or_reset(dev, dev_dax_percpu_exit, &dev_dax->ref);
+ if (rc)
+ return rc;
+
+ dev_dax->pgmap.ref = &dev_dax->ref;
+ addr = devm_memremap_pages(dev, &dev_dax->pgmap);
+ if (IS_ERR(addr)) {
+ devm_remove_action(dev, dev_dax_percpu_exit, &dev_dax->ref);
+ percpu_ref_exit(&dev_dax->ref);
+ return PTR_ERR(addr);
+ }
+
+ rc = devm_add_action_or_reset(dev, dev_dax_percpu_kill,
+ &dev_dax->ref);
+ if (rc)
+ return rc;
+
inode = dax_inode(dax_dev);
cdev = inode->i_cdev;
cdev_init(cdev, &dax_fops);
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c
index c94f17e662bd..d3cefa7868ac 100644
--- a/drivers/dax/pmem.c
+++ b/drivers/dax/pmem.c
@@ -18,55 +18,16 @@
#include "../nvdimm/nd.h"
#include "bus.h"
-struct dax_pmem {
- struct device *dev;
- struct percpu_ref ref;
- struct dev_pagemap pgmap;
- struct completion cmp;
-};
-
-static struct dax_pmem *to_dax_pmem(struct percpu_ref *ref)
-{
- return container_of(ref, struct dax_pmem, ref);
-}
-
-static void dax_pmem_percpu_release(struct percpu_ref *ref)
-{
- struct dax_pmem *dax_pmem = to_dax_pmem(ref);
-
- dev_dbg(dax_pmem->dev, "trace\n");
- complete(&dax_pmem->cmp);
-}
-
-static void dax_pmem_percpu_exit(void *data)
-{
- struct percpu_ref *ref = data;
- struct dax_pmem *dax_pmem = to_dax_pmem(ref);
-
- dev_dbg(dax_pmem->dev, "trace\n");
- wait_for_completion(&dax_pmem->cmp);
- percpu_ref_exit(ref);
-}
-
-static void dax_pmem_percpu_kill(void *data)
-{
- struct percpu_ref *ref = data;
- struct dax_pmem *dax_pmem = to_dax_pmem(ref);
-
- dev_dbg(dax_pmem->dev, "trace\n");
- percpu_ref_kill(ref);
-}
-
static int dax_pmem_probe(struct device *dev)
{
- void *addr;
struct resource res;
int rc, id, region_id;
+ resource_size_t offset;
struct nd_pfn_sb *pfn_sb;
struct dev_dax *dev_dax;
- struct dax_pmem *dax_pmem;
struct nd_namespace_io *nsio;
struct dax_region *dax_region;
+ struct dev_pagemap pgmap = { 0 };
struct nd_namespace_common *ndns;
struct nd_dax *nd_dax = to_nd_dax(dev);
struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
@@ -76,68 +37,37 @@ static int dax_pmem_probe(struct device *dev)
return PTR_ERR(ndns);
nsio = to_nd_namespace_io(&ndns->dev);
- dax_pmem = devm_kzalloc(dev, sizeof(*dax_pmem), GFP_KERNEL);
- if (!dax_pmem)
- return -ENOMEM;
-
/* parse the 'pfn' info block via ->rw_bytes */
rc = devm_nsio_enable(dev, nsio);
if (rc)
return rc;
- rc = nvdimm_setup_pfn(nd_pfn, &dax_pmem->pgmap);
+ rc = nvdimm_setup_pfn(nd_pfn, &pgmap);
if (rc)
return rc;
devm_nsio_disable(dev, nsio);
- pfn_sb = nd_pfn->pfn_sb;
-
- if (!devm_request_mem_region(dev, nsio->res.start,
- resource_size(&nsio->res),
+ /* reserve the metadata area, device-dax will reserve the data */
+ pfn_sb = nd_pfn->pfn_sb;
+ offset = le64_to_cpu(pfn_sb->dataoff);
+ if (!devm_request_mem_region(dev, nsio->res.start, offset,
dev_name(&ndns->dev))) {
- dev_warn(dev, "could not reserve region %pR\n", &nsio->res);
- return -EBUSY;
- }
-
- dax_pmem->dev = dev;
- init_completion(&dax_pmem->cmp);
- rc = percpu_ref_init(&dax_pmem->ref, dax_pmem_percpu_release, 0,
- GFP_KERNEL);
- if (rc)
- return rc;
-
- rc = devm_add_action(dev, dax_pmem_percpu_exit, &dax_pmem->ref);
- if (rc) {
- percpu_ref_exit(&dax_pmem->ref);
- return rc;
- }
-
- dax_pmem->pgmap.ref = &dax_pmem->ref;
- addr = devm_memremap_pages(dev, &dax_pmem->pgmap);
- if (IS_ERR(addr)) {
- devm_remove_action(dev, dax_pmem_percpu_exit, &dax_pmem->ref);
- percpu_ref_exit(&dax_pmem->ref);
- return PTR_ERR(addr);
- }
-
- rc = devm_add_action_or_reset(dev, dax_pmem_percpu_kill,
- &dax_pmem->ref);
- if (rc)
- return rc;
-
- /* adjust the dax_region resource to the start of data */
- memcpy(&res, &dax_pmem->pgmap.res, sizeof(res));
- res.start += le64_to_cpu(pfn_sb->dataoff);
+ dev_warn(dev, "could not reserve metadata\n");
+ return -EBUSY;
+ }
rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", ®ion_id, &id);
if (rc != 2)
return -EINVAL;
+ /* adjust the dax_region resource to the start of data */
+ memcpy(&res, &pgmap.res, sizeof(res));
+ res.start += offset;
dax_region = alloc_dax_region(dev, region_id, &res,
le32_to_cpu(pfn_sb->align), PFN_DEV|PFN_MAP);
if (!dax_region)
return -ENOMEM;
- dev_dax = devm_create_dev_dax(dax_region, id);
+ dev_dax = devm_create_dev_dax(dax_region, id, &pgmap);
/* child dev_dax instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 7/8] device-dax: Add support for a dax override driver
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
` (5 preceding siblings ...)
2018-10-31 3:13 ` [PATCH 6/8] device-dax: Move resource pinning+mapping into the common driver Dan Williams
@ 2018-10-31 3:13 ` Dan Williams
2018-11-07 23:42 ` Williams, Dan J
2018-10-31 3:13 ` [PATCH 8/8] device-dax: Add /sys/class/dax backwards compatibility Dan Williams
7 siblings, 1 reply; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:13 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
Introduce the 'new_id' concept for enabling a custom device-driver attach
policy for dax-bus drivers. The intended use is to have a mechanism for
hot-plugging device-dax ranges into the page allocator on-demand. With
this in place the default policy of using device-dax for performance
differentiated memory can be overridden by user-space policy that can
arrange for the memory range to be managed as 'System RAM' with
user-defined NUMA and other performance attributes.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/bus.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++++--
drivers/dax/bus.h | 10 +++
drivers/dax/device.c | 11 ++--
3 files changed, 156 insertions(+), 10 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 69aae2cbd45f..178d76504f79 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -2,11 +2,21 @@
/* Copyright(c) 2017-2018 Intel Corporation. All rights reserved. */
#include <linux/memremap.h>
#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
#include <linux/slab.h>
#include <linux/dax.h>
#include "dax-private.h"
#include "bus.h"
+static DEFINE_MUTEX(dax_bus_lock);
+
+#define DAX_NAME_LEN 30
+struct dax_id {
+ struct list_head list;
+ char dev_name[DAX_NAME_LEN];
+};
+
static int dax_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
{
/*
@@ -16,22 +26,115 @@ static int dax_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
return add_uevent_var(env, "MODALIAS=" DAX_DEVICE_MODALIAS_FMT, 0);
}
+static struct dax_device_driver *to_dax_drv(struct device_driver *drv)
+{
+ return container_of(drv, struct dax_device_driver, drv);
+}
+
+static struct dax_id *__dax_match_id(struct dax_device_driver *dax_drv,
+ const char *dev_name)
+{
+ struct dax_id *dax_id;
+
+ lockdep_assert_held(&dax_bus_lock);
+
+ list_for_each_entry(dax_id, &dax_drv->ids, list)
+ if (strcmp(dax_id->dev_name, dev_name) == 0)
+ return dax_id;
+ return NULL;
+}
+
+static int dax_match_id(struct dax_device_driver *dax_drv, struct device *dev)
+{
+ int match;
+
+ mutex_lock(&dax_bus_lock);
+ match = !!__dax_match_id(dax_drv, dev_name(dev));
+ mutex_unlock(&dax_bus_lock);
+
+ return match;
+}
+
+static ssize_t do_id_store(struct device_driver *drv, const char *buf,
+ size_t count, bool add)
+{
+ struct dax_device_driver *dax_drv = to_dax_drv(drv);
+ unsigned int region_id, id;
+ struct dax_id *dax_id;
+ ssize_t rc = count;
+ int fields;
+
+ fields = sscanf(buf, "dax%d.%d", ®ion_id, &id);
+ if (fields != 2)
+ return -EINVAL;
+
+ if (strlen(buf) + 1 > DAX_NAME_LEN)
+ return -EINVAL;
+
+ mutex_lock(&dax_bus_lock);
+ dax_id = __dax_match_id(dax_drv, buf);
+ if (!dax_id) {
+ if (add) {
+ dax_id = kzalloc(sizeof(*dax_id), GFP_KERNEL);
+ if (dax_id) {
+ strncpy(dax_id->dev_name, buf, DAX_NAME_LEN);
+ list_add(&dax_id->list, &dax_drv->ids);
+ } else
+ rc = -ENOMEM;
+ } else
+ /* nothing to remove */;
+ } else if (!add) {
+ list_del(&dax_id->list);
+ kfree(dax_id);
+ } else
+ /* dax_id already added */;
+ mutex_unlock(&dax_bus_lock);
+ return rc;
+}
+
+static ssize_t new_id_store(struct device_driver *drv, const char *buf,
+ size_t count)
+{
+ return do_id_store(drv, buf, count, true);
+}
+static DRIVER_ATTR_WO(new_id);
+
+
+static ssize_t remove_id_store(struct device_driver *drv, const char *buf,
+ size_t count)
+{
+ return do_id_store(drv, buf, count, false);
+}
+static DRIVER_ATTR_WO(remove_id);
+
+static struct attribute *dax_drv_attrs[] = {
+ &driver_attr_new_id.attr,
+ &driver_attr_remove_id.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(dax_drv);
+
static int dax_bus_match(struct device *dev, struct device_driver *drv);
static struct bus_type dax_bus_type = {
.name = "dax",
.uevent = dax_bus_uevent,
.match = dax_bus_match,
+ .drv_groups = dax_drv_groups,
};
static int dax_bus_match(struct device *dev, struct device_driver *drv)
{
+ struct dax_device_driver *dax_drv = to_dax_drv(drv);
+
/*
- * The drivers that can register on the 'dax' bus are private to
- * drivers/dax/ so any device and driver on the bus always
- * match.
+ * All but the 'device-dax' driver, which has 'match_always'
+ * set, requires an exact id match.
*/
- return 1;
+ if (dax_drv->match_always)
+ return 1;
+
+ return dax_match_id(dax_drv, dev);
}
/*
@@ -273,17 +376,49 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
}
EXPORT_SYMBOL_GPL(devm_create_dev_dax);
-int __dax_driver_register(struct device_driver *drv,
+static int match_always_count;
+
+int __dax_driver_register(struct dax_device_driver *dax_drv,
struct module *module, const char *mod_name)
{
+ struct device_driver *drv = &dax_drv->drv;
+ int rc = 0;
+
+ INIT_LIST_HEAD(&dax_drv->ids);
drv->owner = module;
drv->name = mod_name;
drv->mod_name = mod_name;
drv->bus = &dax_bus_type;
+
+ /* there can only be one default driver */
+ mutex_lock(&dax_bus_lock);
+ match_always_count += dax_drv->match_always;
+ if (match_always_count > 1) {
+ match_always_count--;
+ WARN_ON(1);
+ rc = -EINVAL;
+ }
+ mutex_unlock(&dax_bus_lock);
+ if (rc)
+ return rc;
return driver_register(drv);
}
EXPORT_SYMBOL_GPL(__dax_driver_register);
+void dax_driver_unregister(struct dax_device_driver *dax_drv)
+{
+ struct dax_id *dax_id, *_id;
+
+ mutex_lock(&dax_bus_lock);
+ match_always_count -= dax_drv->match_always;
+ list_for_each_entry_safe(dax_id, _id, &dax_drv->ids, list) {
+ list_del(&dax_id->list);
+ kfree(dax_id);
+ }
+ mutex_unlock(&dax_bus_lock);
+}
+EXPORT_SYMBOL_GPL(dax_driver_unregister);
+
int __init dax_bus_init(void)
{
return bus_register(&dax_bus_type);
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h
index e08e0c394983..395ab812367c 100644
--- a/drivers/dax/bus.h
+++ b/drivers/dax/bus.h
@@ -12,10 +12,18 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct resource *res, unsigned int align, unsigned long flags);
struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
struct dev_pagemap *pgmap);
-int __dax_driver_register(struct device_driver *drv,
+
+struct dax_device_driver {
+ struct device_driver drv;
+ struct list_head ids;
+ int match_always;
+};
+
+int __dax_driver_register(struct dax_device_driver *dax_drv,
struct module *module, const char *mod_name);
#define dax_driver_register(driver) \
__dax_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
+void dax_driver_unregister(struct dax_device_driver *dax_drv);
void kill_dev_dax(struct dev_dax *dev_dax);
/*
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 967bab097013..052aed3ab600 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -508,9 +508,12 @@ static int dev_dax_remove(struct device *dev)
return 0;
}
-static struct device_driver device_dax_driver = {
- .probe = dev_dax_probe,
- .remove = dev_dax_remove,
+static struct dax_device_driver device_dax_driver = {
+ .drv = {
+ .probe = dev_dax_probe,
+ .remove = dev_dax_remove,
+ },
+ .match_always = 1,
};
static int __init dax_init(void)
@@ -520,7 +523,7 @@ static int __init dax_init(void)
static void __exit dax_exit(void)
{
- driver_unregister(&device_dax_driver);
+ dax_driver_unregister(&device_dax_driver);
}
MODULE_AUTHOR("Intel Corporation");
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH 8/8] device-dax: Add /sys/class/dax backwards compatibility
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
` (6 preceding siblings ...)
2018-10-31 3:13 ` [PATCH 7/8] device-dax: Add support for a dax override driver Dan Williams
@ 2018-10-31 3:13 ` Dan Williams
7 siblings, 0 replies; 10+ messages in thread
From: Dan Williams @ 2018-10-31 3:13 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-mm, linux-kernel, dave.hansen
On the expectation that some environments may not upgrade libdaxctl
(userspace component that depends on the /sys/class/dax hierarchy),
provide a default / legacy dax_pmem_compat driver. The dax_pmem_compat
driver implements the original /sys/class/dax sysfs layout rather than
/sys/bus/dax. When userspace is upgraded it can blacklist this module
and switch to the dax_pmem driver going forward.
CONFIG_DEV_DAX_PMEM_COMPAT and supporting code will be deleted according
to the dax_pmem entry in Documentation/ABI/obsolete/.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
Documentation/ABI/obsolete/sysfs-class-dax | 22 +++++++
drivers/dax/Kconfig | 12 +++-
drivers/dax/Makefile | 4 +
drivers/dax/bus.c | 29 +++++++--
drivers/dax/bus.h | 26 +++++++-
drivers/dax/device.c | 9 ++-
drivers/dax/pmem.c | 90 ----------------------------
drivers/dax/pmem/Makefile | 7 ++
drivers/dax/pmem/compat.c | 73 +++++++++++++++++++++++
drivers/dax/pmem/core.c | 69 +++++++++++++++++++++
drivers/dax/pmem/pmem.c | 40 ++++++++++++
tools/testing/nvdimm/Kbuild | 6 ++
12 files changed, 283 insertions(+), 104 deletions(-)
create mode 100644 Documentation/ABI/obsolete/sysfs-class-dax
delete mode 100644 drivers/dax/pmem.c
create mode 100644 drivers/dax/pmem/Makefile
create mode 100644 drivers/dax/pmem/compat.c
create mode 100644 drivers/dax/pmem/core.c
create mode 100644 drivers/dax/pmem/pmem.c
diff --git a/Documentation/ABI/obsolete/sysfs-class-dax b/Documentation/ABI/obsolete/sysfs-class-dax
new file mode 100644
index 000000000000..2cb9fc5e8bd1
--- /dev/null
+++ b/Documentation/ABI/obsolete/sysfs-class-dax
@@ -0,0 +1,22 @@
+What: /sys/class/dax/
+Date: May, 2016
+KernelVersion: v4.7
+Contact: linux-nvdimm@lists.01.org
+Description: Device DAX is the device-centric analogue of Filesystem
+ DAX (CONFIG_FS_DAX). It allows memory ranges to be
+ allocated and mapped without need of an intervening file
+ system. Device DAX is strict, precise and predictable.
+ Specifically this interface:
+
+ 1/ Guarantees fault granularity with respect to a given
+ page size (pte, pmd, or pud) set at configuration time.
+
+ 2/ Enforces deterministic behavior by being strict about
+ what fault scenarios are supported.
+
+ The /sys/class/dax/ interface enumerates all the
+ device-dax instances in the system. The ABI is
+ deprecated and will be removed after 2020. It is
+ replaced with the DAX bus interface /sys/bus/dax/ where
+ device-dax instances can be found under
+ /sys/bus/dax/devices/
diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
index e0700bf4893a..6fc96f03920e 100644
--- a/drivers/dax/Kconfig
+++ b/drivers/dax/Kconfig
@@ -23,12 +23,22 @@ config DEV_DAX
config DEV_DAX_PMEM
tristate "PMEM DAX: direct access to persistent memory"
depends on LIBNVDIMM && NVDIMM_DAX && DEV_DAX
+ depends on m # until we can kill DEV_DAX_PMEM_COMPAT
default DEV_DAX
help
Support raw access to persistent memory. Note that this
driver consumes memory ranges allocated and exported by the
libnvdimm sub-system.
- Say Y if unsure
+ Say M if unsure
+
+config DEV_DAX_PMEM_COMPAT
+ tristate "PMEM DAX: support the deprecated /sys/class/dax interface"
+ depends on DEV_DAX_PMEM
+ default DEV_DAX_PMEM
+ help
+ Older versions of the libdaxctl library expect to find all
+ device-dax instances under /sys/class/dax. If libdaxctl in
+ your distribution is older than v58 say M, otherwise say N.
endif
diff --git a/drivers/dax/Makefile b/drivers/dax/Makefile
index 658e6b9b1d74..233bbffccbe6 100644
--- a/drivers/dax/Makefile
+++ b/drivers/dax/Makefile
@@ -1,9 +1,9 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_DAX) += dax.o
obj-$(CONFIG_DEV_DAX) += device_dax.o
-obj-$(CONFIG_DEV_DAX_PMEM) += dax_pmem.o
dax-y := super.o
dax-y += bus.o
-dax_pmem-y := pmem.o
device_dax-y := device.o
+
+obj-y += pmem/
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 178d76504f79..ebf9a4726f6c 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -9,6 +9,8 @@
#include "dax-private.h"
#include "bus.h"
+static struct class *dax_class;
+
static DEFINE_MUTEX(dax_bus_lock);
#define DAX_NAME_LEN 30
@@ -310,8 +312,8 @@ static void unregister_dev_dax(void *dev)
put_device(dev);
}
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
- struct dev_pagemap *pgmap)
+struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id,
+ struct dev_pagemap *pgmap, enum dev_dax_subsys subsys)
{
struct device *parent = dax_region->dev;
struct dax_device *dax_dev;
@@ -350,7 +352,10 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
inode = dax_inode(dax_dev);
dev->devt = inode->i_rdev;
- dev->bus = &dax_bus_type;
+ if (subsys == DEV_DAX_BUS)
+ dev->bus = &dax_bus_type;
+ else
+ dev->class = dax_class;
dev->parent = parent;
dev->groups = dax_attribute_groups;
dev->release = dev_dax_release;
@@ -374,7 +379,7 @@ struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
return ERR_PTR(rc);
}
-EXPORT_SYMBOL_GPL(devm_create_dev_dax);
+EXPORT_SYMBOL_GPL(__devm_create_dev_dax);
static int match_always_count;
@@ -407,6 +412,7 @@ EXPORT_SYMBOL_GPL(__dax_driver_register);
void dax_driver_unregister(struct dax_device_driver *dax_drv)
{
+ struct device_driver *drv = &dax_drv->drv;
struct dax_id *dax_id, *_id;
mutex_lock(&dax_bus_lock);
@@ -416,15 +422,28 @@ void dax_driver_unregister(struct dax_device_driver *dax_drv)
kfree(dax_id);
}
mutex_unlock(&dax_bus_lock);
+ driver_unregister(drv);
}
EXPORT_SYMBOL_GPL(dax_driver_unregister);
int __init dax_bus_init(void)
{
- return bus_register(&dax_bus_type);
+ int rc;
+
+ if (IS_ENABLED(CONFIG_DEV_DAX_PMEM_COMPAT)) {
+ dax_class = class_create(THIS_MODULE, "dax");
+ if (IS_ERR(dax_class))
+ return PTR_ERR(dax_class);
+ }
+
+ rc = bus_register(&dax_bus_type);
+ if (rc)
+ class_destroy(dax_class);
+ return rc;
}
void __exit dax_bus_exit(void)
{
bus_unregister(&dax_bus_type);
+ class_destroy(dax_class);
}
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h
index 395ab812367c..ce977552ffb5 100644
--- a/drivers/dax/bus.h
+++ b/drivers/dax/bus.h
@@ -2,7 +2,8 @@
/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
#ifndef __DAX_BUS_H__
#define __DAX_BUS_H__
-struct device;
+#include <linux/device.h>
+
struct dev_dax;
struct resource;
struct dax_device;
@@ -10,8 +11,23 @@ struct dax_region;
void dax_region_put(struct dax_region *dax_region);
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct resource *res, unsigned int align, unsigned long flags);
-struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, int id,
- struct dev_pagemap *pgmap);
+
+enum dev_dax_subsys {
+ DEV_DAX_BUS,
+ DEV_DAX_CLASS,
+};
+
+struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id,
+ struct dev_pagemap *pgmap, enum dev_dax_subsys subsys);
+
+static inline struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region,
+ int id, struct dev_pagemap *pgmap)
+{
+ return __devm_create_dev_dax(dax_region, id, pgmap, DEV_DAX_BUS);
+}
+
+/* to be deleted when DEV_DAX_CLASS is removed */
+struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys);
struct dax_device_driver {
struct device_driver drv;
@@ -26,6 +42,10 @@ int __dax_driver_register(struct dax_device_driver *dax_drv,
void dax_driver_unregister(struct dax_device_driver *dax_drv);
void kill_dev_dax(struct dev_dax *dev_dax);
+#if IS_ENABLED(CONFIG_DEV_DAX_PMEM_COMPAT)
+int dev_dax_probe(struct device *dev);
+#endif
+
/*
* While run_dax() is potentially a generic operation that could be
* defined in include/linux/dax.h we don't want to grow any users
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 052aed3ab600..71694cd984a3 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -445,7 +445,7 @@ static void dev_dax_kill(void *dev_dax)
kill_dev_dax(dev_dax);
}
-static int dev_dax_probe(struct device *dev)
+int dev_dax_probe(struct device *dev)
{
struct dev_dax *dev_dax = to_dev_dax(dev);
struct dax_device *dax_dev = dev_dax->dax_dev;
@@ -488,7 +488,11 @@ static int dev_dax_probe(struct device *dev)
inode = dax_inode(dax_dev);
cdev = inode->i_cdev;
cdev_init(cdev, &dax_fops);
- cdev->owner = dev->driver->owner;
+ if (dev->class) {
+ /* for the CONFIG_DEV_DAX_PMEM_COMPAT case */
+ cdev->owner = dev->parent->driver->owner;
+ } else
+ cdev->owner = dev->driver->owner;
cdev_set_parent(cdev, &dev->kobj);
rc = cdev_add(cdev, dev->devt, 1);
if (rc)
@@ -501,6 +505,7 @@ static int dev_dax_probe(struct device *dev)
run_dax(dax_dev);
return devm_add_action_or_reset(dev, dev_dax_kill, dev_dax);
}
+EXPORT_SYMBOL_GPL(dev_dax_probe);
static int dev_dax_remove(struct device *dev)
{
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c
deleted file mode 100644
index d3cefa7868ac..000000000000
--- a/drivers/dax/pmem.c
+++ /dev/null
@@ -1,90 +0,0 @@
-/*
- * Copyright(c) 2016 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
-#include <linux/percpu-refcount.h>
-#include <linux/memremap.h>
-#include <linux/module.h>
-#include <linux/pfn_t.h>
-#include "../nvdimm/pfn.h"
-#include "../nvdimm/nd.h"
-#include "bus.h"
-
-static int dax_pmem_probe(struct device *dev)
-{
- struct resource res;
- int rc, id, region_id;
- resource_size_t offset;
- struct nd_pfn_sb *pfn_sb;
- struct dev_dax *dev_dax;
- struct nd_namespace_io *nsio;
- struct dax_region *dax_region;
- struct dev_pagemap pgmap = { 0 };
- struct nd_namespace_common *ndns;
- struct nd_dax *nd_dax = to_nd_dax(dev);
- struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
-
- ndns = nvdimm_namespace_common_probe(dev);
- if (IS_ERR(ndns))
- return PTR_ERR(ndns);
- nsio = to_nd_namespace_io(&ndns->dev);
-
- /* parse the 'pfn' info block via ->rw_bytes */
- rc = devm_nsio_enable(dev, nsio);
- if (rc)
- return rc;
- rc = nvdimm_setup_pfn(nd_pfn, &pgmap);
- if (rc)
- return rc;
- devm_nsio_disable(dev, nsio);
-
- /* reserve the metadata area, device-dax will reserve the data */
- pfn_sb = nd_pfn->pfn_sb;
- offset = le64_to_cpu(pfn_sb->dataoff);
- if (!devm_request_mem_region(dev, nsio->res.start, offset,
- dev_name(&ndns->dev))) {
- dev_warn(dev, "could not reserve metadata\n");
- return -EBUSY;
- }
-
- rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", ®ion_id, &id);
- if (rc != 2)
- return -EINVAL;
-
- /* adjust the dax_region resource to the start of data */
- memcpy(&res, &pgmap.res, sizeof(res));
- res.start += offset;
- dax_region = alloc_dax_region(dev, region_id, &res,
- le32_to_cpu(pfn_sb->align), PFN_DEV|PFN_MAP);
- if (!dax_region)
- return -ENOMEM;
-
- dev_dax = devm_create_dev_dax(dax_region, id, &pgmap);
-
- /* child dev_dax instances now own the lifetime of the dax_region */
- dax_region_put(dax_region);
-
- return PTR_ERR_OR_ZERO(dev_dax);
-}
-
-static struct nd_device_driver dax_pmem_driver = {
- .probe = dax_pmem_probe,
- .drv = {
- .name = "dax_pmem",
- },
- .type = ND_DRIVER_DAX_PMEM,
-};
-
-module_nd_driver(dax_pmem_driver);
-
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Intel Corporation");
-MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM);
diff --git a/drivers/dax/pmem/Makefile b/drivers/dax/pmem/Makefile
new file mode 100644
index 000000000000..e2e79bd3fdcf
--- /dev/null
+++ b/drivers/dax/pmem/Makefile
@@ -0,0 +1,7 @@
+obj-$(CONFIG_DEV_DAX_PMEM) += dax_pmem.o
+obj-$(CONFIG_DEV_DAX_PMEM) += dax_pmem_core.o
+obj-$(CONFIG_DEV_DAX_PMEM_COMPAT) += dax_pmem_compat.o
+
+dax_pmem-y := pmem.o
+dax_pmem_core-y := core.o
+dax_pmem_compat-y := compat.o
diff --git a/drivers/dax/pmem/compat.c b/drivers/dax/pmem/compat.c
new file mode 100644
index 000000000000..d7b15e6f30c5
--- /dev/null
+++ b/drivers/dax/pmem/compat.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
+#include <linux/percpu-refcount.h>
+#include <linux/memremap.h>
+#include <linux/module.h>
+#include <linux/pfn_t.h>
+#include <linux/nd.h>
+#include "../bus.h"
+
+/* we need the private definitions to implement compat suport */
+#include "../dax-private.h"
+
+static int dax_pmem_compat_probe(struct device *dev)
+{
+ struct dev_dax *dev_dax = __dax_pmem_probe(dev, DEV_DAX_CLASS);
+ int rc;
+
+ if (IS_ERR(dev_dax))
+ return PTR_ERR(dev_dax);
+
+ if (!devres_open_group(&dev_dax->dev, dev_dax, GFP_KERNEL))
+ return -ENOMEM;
+
+ device_lock(&dev_dax->dev);
+ rc = dev_dax_probe(&dev_dax->dev);
+ device_unlock(&dev_dax->dev);
+
+ devres_close_group(&dev_dax->dev, dev_dax);
+ if (rc)
+ devres_release_group(&dev_dax->dev, dev_dax);
+
+ return rc;
+}
+
+static int dax_pmem_compat_release(struct device *dev, void *data)
+{
+ device_lock(dev);
+ devres_release_group(dev, to_dev_dax(dev));
+ device_unlock(dev);
+
+ return 0;
+}
+
+static int dax_pmem_compat_remove(struct device *dev)
+{
+ device_for_each_child(dev, NULL, dax_pmem_compat_release);
+ return 0;
+}
+
+static struct nd_device_driver dax_pmem_compat_driver = {
+ .probe = dax_pmem_compat_probe,
+ .remove = dax_pmem_compat_remove,
+ .drv = {
+ .name = "dax_pmem_compat",
+ },
+ .type = ND_DRIVER_DAX_PMEM,
+};
+
+static int __init dax_pmem_compat_init(void)
+{
+ return nd_driver_register(&dax_pmem_compat_driver);
+}
+module_init(dax_pmem_compat_init);
+
+static void __exit dax_pmem_compat_exit(void)
+{
+ driver_unregister(&dax_pmem_compat_driver.drv);
+}
+module_exit(dax_pmem_compat_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM);
diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c
new file mode 100644
index 000000000000..bdcff1b14e95
--- /dev/null
+++ b/drivers/dax/pmem/core.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
+#include <linux/memremap.h>
+#include <linux/module.h>
+#include <linux/pfn_t.h>
+#include "../../nvdimm/pfn.h"
+#include "../../nvdimm/nd.h"
+#include "../bus.h"
+
+struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys)
+{
+ struct resource res;
+ int rc, id, region_id;
+ resource_size_t offset;
+ struct nd_pfn_sb *pfn_sb;
+ struct dev_dax *dev_dax;
+ struct nd_namespace_io *nsio;
+ struct dax_region *dax_region;
+ struct dev_pagemap pgmap = { 0 };
+ struct nd_namespace_common *ndns;
+ struct nd_dax *nd_dax = to_nd_dax(dev);
+ struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
+
+ ndns = nvdimm_namespace_common_probe(dev);
+ if (IS_ERR(ndns))
+ return ERR_CAST(ndns);
+ nsio = to_nd_namespace_io(&ndns->dev);
+
+ /* parse the 'pfn' info block via ->rw_bytes */
+ rc = devm_nsio_enable(dev, nsio);
+ if (rc)
+ return ERR_PTR(rc);
+ rc = nvdimm_setup_pfn(nd_pfn, &pgmap);
+ if (rc)
+ return ERR_PTR(rc);
+ devm_nsio_disable(dev, nsio);
+
+ /* reserve the metadata area, device-dax will reserve the data */
+ pfn_sb = nd_pfn->pfn_sb;
+ offset = le64_to_cpu(pfn_sb->dataoff);
+ if (!devm_request_mem_region(dev, nsio->res.start, offset,
+ dev_name(&ndns->dev))) {
+ dev_warn(dev, "could not reserve metadata\n");
+ return ERR_PTR(-EBUSY);
+ }
+
+ rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", ®ion_id, &id);
+ if (rc != 2)
+ return ERR_PTR(-EINVAL);
+
+ /* adjust the dax_region resource to the start of data */
+ memcpy(&res, &pgmap.res, sizeof(res));
+ res.start += offset;
+ dax_region = alloc_dax_region(dev, region_id, &res,
+ le32_to_cpu(pfn_sb->align), PFN_DEV|PFN_MAP);
+ if (!dax_region)
+ return ERR_PTR(-ENOMEM);
+
+ dev_dax = __devm_create_dev_dax(dax_region, id, &pgmap, subsys);
+
+ /* child dev_dax instances now own the lifetime of the dax_region */
+ dax_region_put(dax_region);
+
+ return dev_dax;
+}
+EXPORT_SYMBOL_GPL(__dax_pmem_probe);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Intel Corporation");
diff --git a/drivers/dax/pmem/pmem.c b/drivers/dax/pmem/pmem.c
new file mode 100644
index 000000000000..0ae4238a0ef8
--- /dev/null
+++ b/drivers/dax/pmem/pmem.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */
+#include <linux/percpu-refcount.h>
+#include <linux/memremap.h>
+#include <linux/module.h>
+#include <linux/pfn_t.h>
+#include <linux/nd.h>
+#include "../bus.h"
+
+static int dax_pmem_probe(struct device *dev)
+{
+ return PTR_ERR_OR_ZERO(__dax_pmem_probe(dev, DEV_DAX_BUS));
+}
+
+static struct nd_device_driver dax_pmem_driver = {
+ .probe = dax_pmem_probe,
+ .drv = {
+ .name = "dax_pmem",
+ },
+ .type = ND_DRIVER_DAX_PMEM,
+};
+
+static int __init dax_pmem_init(void)
+{
+ return nd_driver_register(&dax_pmem_driver);
+}
+module_init(dax_pmem_init);
+
+static void __exit dax_pmem_exit(void)
+{
+ driver_unregister(&dax_pmem_driver.drv);
+}
+module_exit(dax_pmem_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Intel Corporation");
+#if !IS_ENABLED(CONFIG_DEV_DAX_PMEM_COMPAT)
+/* For compat builds, don't load this module by default */
+MODULE_ALIAS_ND_DEVICE(ND_DEVICE_DAX_PMEM);
+#endif
diff --git a/tools/testing/nvdimm/Kbuild b/tools/testing/nvdimm/Kbuild
index bfc4d8e98452..1e37719bc37e 100644
--- a/tools/testing/nvdimm/Kbuild
+++ b/tools/testing/nvdimm/Kbuild
@@ -34,6 +34,8 @@ obj-$(CONFIG_DAX) += dax.o
endif
obj-$(CONFIG_DEV_DAX) += device_dax.o
obj-$(CONFIG_DEV_DAX_PMEM) += dax_pmem.o
+obj-$(CONFIG_DEV_DAX_PMEM) += dax_pmem_core.o
+obj-$(CONFIG_DEV_DAX_PMEM_COMPAT) += dax_pmem_compat.o
nfit-y := $(ACPI_SRC)/core.o
nfit-$(CONFIG_X86_MCE) += $(ACPI_SRC)/mce.o
@@ -63,7 +65,9 @@ device_dax-y += dax-dev.o
device_dax-y += device_dax_test.o
device_dax-y += config_check.o
-dax_pmem-y := $(DAX_SRC)/pmem.o
+dax_pmem-y := $(DAX_SRC)/pmem/pmem.o
+dax_pmem_core-y := $(DAX_SRC)/pmem/core.o
+dax_pmem_compat-y := $(DAX_SRC)/pmem/compat.o
dax_pmem-y += config_check.o
libnvdimm-y := $(NVDIMM_SRC)/core.o
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH 7/8] device-dax: Add support for a dax override driver
2018-10-31 3:13 ` [PATCH 7/8] device-dax: Add support for a dax override driver Dan Williams
@ 2018-11-07 23:42 ` Williams, Dan J
0 siblings, 0 replies; 10+ messages in thread
From: Williams, Dan J @ 2018-11-07 23:42 UTC (permalink / raw)
To: linux-nvdimm; +Cc: linux-kernel, linux-mm, dave.hansen
On Tue, 2018-10-30 at 20:13 -0700, Dan Williams wrote:
> Introduce the 'new_id' concept for enabling a custom device-driver attach
> policy for dax-bus drivers. The intended use is to have a mechanism for
> hot-plugging device-dax ranges into the page allocator on-demand. With
> this in place the default policy of using device-dax for performance
> differentiated memory can be overridden by user-space policy that can
> arrange for the memory range to be managed as 'System RAM' with
> user-defined NUMA and other performance attributes.
>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
> drivers/dax/bus.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++++--
> drivers/dax/bus.h | 10 +++
> drivers/dax/device.c | 11 ++--
> 3 files changed, 156 insertions(+), 10 deletions(-)
>
>
Here's an incremental fixup for the string matching in this patch, I'll
send a v2 if other review comments come in:
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index 178d76504f79..17af6fbc3be5 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -39,7 +39,7 @@ static struct dax_id *__dax_match_id(struct dax_device_driver *dax_drv,
lockdep_assert_held(&dax_bus_lock);
list_for_each_entry(dax_id, &dax_drv->ids, list)
- if (strcmp(dax_id->dev_name, dev_name) == 0)
+ if (sysfs_streq(dax_id->dev_name, dev_name))
return dax_id;
return NULL;
}
@@ -60,6 +60,7 @@ static ssize_t do_id_store(struct device_driver *drv, const char *buf,
{
struct dax_device_driver *dax_drv = to_dax_drv(drv);
unsigned int region_id, id;
+ char devname[DAX_NAME_LEN];
struct dax_id *dax_id;
ssize_t rc = count;
int fields;
@@ -67,8 +68,8 @@ static ssize_t do_id_store(struct device_driver *drv, const char *buf,
fields = sscanf(buf, "dax%d.%d", ®ion_id, &id);
if (fields != 2)
return -EINVAL;
-
- if (strlen(buf) + 1 > DAX_NAME_LEN)
+ sprintf(devname, "dax%d.%d", region_id, id);
+ if (!sysfs_streq(buf, devname))
return -EINVAL;
mutex_lock(&dax_bus_lock);
@@ -99,7 +100,6 @@ static ssize_t new_id_store(struct device_driver *drv, const char *buf,
}
static DRIVER_ATTR_WO(new_id);
-
static ssize_t remove_id_store(struct device_driver *drv, const char *buf,
size_t count)
{
^ permalink raw reply related [flat|nested] 10+ messages in thread
end of thread, other threads:[~2018-11-07 23:42 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-10-31 3:12 [PATCH 0/8] Introduce a device-dax bus-based device-model Dan Williams
2018-10-31 3:12 ` [PATCH 1/8] device-dax: Kill dax_region ida Dan Williams
2018-10-31 3:13 ` [PATCH 2/8] device-dax: Kill dax_region base Dan Williams
2018-10-31 3:13 ` [PATCH 3/8] device-dax: Remove multi-resource infrastructure Dan Williams
2018-10-31 3:13 ` [PATCH 4/8] device-dax: Start defining a dax bus model Dan Williams
2018-10-31 3:13 ` [PATCH 5/8] device-dax: Introduce bus + driver model Dan Williams
2018-10-31 3:13 ` [PATCH 6/8] device-dax: Move resource pinning+mapping into the common driver Dan Williams
2018-10-31 3:13 ` [PATCH 7/8] device-dax: Add support for a dax override driver Dan Williams
2018-11-07 23:42 ` Williams, Dan J
2018-10-31 3:13 ` [PATCH 8/8] device-dax: Add /sys/class/dax backwards compatibility Dan Williams
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