This is a note to let you know that I've just added the patch titled
device-dax: fix sysfs duplicate warnings
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
device-dax-fix-sysfs-duplicate-warnings.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From bbb3be170ac2891526ad07b18af7db226879a8e7 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@xxxxxxxxx>
Date: Tue, 18 Jul 2017 17:49:14 -0700
Subject: device-dax: fix sysfs duplicate warnings
From: Dan Williams <dan.j.williams@xxxxxxxxx>
commit bbb3be170ac2891526ad07b18af7db226879a8e7 upstream.
Fix warnings of the form...
WARNING: CPU: 10 PID: 4983 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80
sysfs: cannot create duplicate filename '/class/dax/dax12.0'
Call Trace:
dump_stack+0x63/0x86
__warn+0xcb/0xf0
warn_slowpath_fmt+0x5a/0x80
? kernfs_path_from_node+0x4f/0x60
sysfs_warn_dup+0x62/0x80
sysfs_do_create_link_sd.isra.2+0x97/0xb0
sysfs_create_link+0x25/0x40
device_add+0x266/0x630
devm_create_dax_dev+0x2cf/0x340 [dax]
dax_pmem_probe+0x1f5/0x26e [dax_pmem]
nvdimm_bus_probe+0x71/0x120
...by reusing the namespace id for the device-dax instance name.
Now that we have decided that there will never by more than one
device-dax instance per libnvdimm-namespace parent device [1], we can
directly reuse the namepace ids. There are some possible follow-on
cleanups, but those are saved for a later patch to simplify the -stable
backport.
[1]: https://lists.01.org/pipermail/linux-nvdimm/2016-December/008266.html
Fixes: 98a29c39dc68 ("libnvdimm, namespace: allow creation of multiple pmem...")
Cc: Jeff Moyer <jmoyer@xxxxxxxxxx>
Reported-by: Dariusz Dokupil <dariusz.dokupil@xxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dax/dax.c | 24 ++++++++++++++++--------
drivers/dax/dax.h | 2 +-
drivers/dax/pmem.c | 12 +++++++-----
3 files changed, 24 insertions(+), 14 deletions(-)
--- a/drivers/dax/dax.c
+++ b/drivers/dax/dax.c
@@ -546,7 +546,8 @@ static void dax_dev_release(struct devic
struct dax_dev *dax_dev = to_dax_dev(dev);
struct dax_region *dax_region = dax_dev->region;
- ida_simple_remove(&dax_region->ida, dax_dev->id);
+ if (dax_dev->id >= 0)
+ ida_simple_remove(&dax_region->ida, dax_dev->id);
ida_simple_remove(&dax_minor_ida, MINOR(dev->devt));
dax_region_put(dax_region);
iput(dax_dev->inode);
@@ -581,7 +582,7 @@ static void unregister_dax_dev(void *dev
}
struct dax_dev *devm_create_dax_dev(struct dax_region *dax_region,
- struct resource *res, int count)
+ int id, struct resource *res, int count)
{
struct device *parent = dax_region->dev;
struct dax_dev *dax_dev;
@@ -608,10 +609,16 @@ struct dax_dev *devm_create_dax_dev(stru
if (i < count)
goto err_id;
- dax_dev->id = ida_simple_get(&dax_region->ida, 0, 0, GFP_KERNEL);
- if (dax_dev->id < 0) {
- rc = dax_dev->id;
- goto err_id;
+ if (id < 0) {
+ id = ida_simple_get(&dax_region->ida, 0, 0, GFP_KERNEL);
+ dax_dev->id = id;
+ if (id < 0) {
+ rc = id;
+ goto err_id;
+ }
+ } else {
+ /* region provider owns @id lifetime */
+ dax_dev->id = -1;
}
minor = ida_simple_get(&dax_minor_ida, 0, 0, GFP_KERNEL);
@@ -650,7 +657,7 @@ struct dax_dev *devm_create_dax_dev(stru
dev->parent = parent;
dev->groups = dax_attribute_groups;
dev->release = dax_dev_release;
- dev_set_name(dev, "dax%d.%d", dax_region->id, dax_dev->id);
+ dev_set_name(dev, "dax%d.%d", dax_region->id, id);
rc = device_add(dev);
if (rc) {
kill_dax_dev(dax_dev);
@@ -669,7 +676,8 @@ struct dax_dev *devm_create_dax_dev(stru
err_inode:
ida_simple_remove(&dax_minor_ida, minor);
err_minor:
- ida_simple_remove(&dax_region->ida, dax_dev->id);
+ if (dax_dev->id >= 0)
+ ida_simple_remove(&dax_region->ida, dax_dev->id);
err_id:
kfree(dax_dev);
--- a/drivers/dax/dax.h
+++ b/drivers/dax/dax.h
@@ -21,5 +21,5 @@ struct dax_region *alloc_dax_region(stru
int region_id, struct resource *res, unsigned int align,
void *addr, unsigned long flags);
struct dax_dev *devm_create_dax_dev(struct dax_region *dax_region,
- struct resource *res, int count);
+ int id, struct resource *res, int count);
#endif /* __DAX_H__ */
--- a/drivers/dax/pmem.c
+++ b/drivers/dax/pmem.c
@@ -58,13 +58,12 @@ static void dax_pmem_percpu_kill(void *d
static int dax_pmem_probe(struct device *dev)
{
- int rc;
void *addr;
struct resource res;
struct dax_dev *dax_dev;
+ int rc, id, region_id;
struct nd_pfn_sb *pfn_sb;
struct dax_pmem *dax_pmem;
- struct nd_region *nd_region;
struct nd_namespace_io *nsio;
struct dax_region *dax_region;
struct nd_namespace_common *ndns;
@@ -122,14 +121,17 @@ static int dax_pmem_probe(struct device
/* adjust the dax_region resource to the start of data */
res.start += le64_to_cpu(pfn_sb->dataoff);
- nd_region = to_nd_region(dev->parent);
- dax_region = alloc_dax_region(dev, nd_region->id, &res,
+ rc = sscanf(dev_name(&ndns->dev), "namespace%d.%d", ®ion_id, &id);
+ if (rc != 2)
+ return -EINVAL;
+
+ dax_region = alloc_dax_region(dev, region_id, &res,
le32_to_cpu(pfn_sb->align), addr, PFN_DEV|PFN_MAP);
if (!dax_region)
return -ENOMEM;
/* TODO: support for subdividing a dax region... */
- dax_dev = devm_create_dax_dev(dax_region, &res, 1);
+ dax_dev = devm_create_dax_dev(dax_region, id, &res, 1);
/* child dax_dev instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
Patches currently in stable-queue which might be from dan.j.williams@xxxxxxxxx are
queue-4.9/device-dax-fix-sysfs-duplicate-warnings.patch