[PATCH 6/7] sysfs: clean up sysfs_get_dirent()

Tejun Heo
2013-09-12T02:30:00Z

The pre-existing sysfs interfaces which take explicit namespace
argument are weird in that they place the optional @ns in front of
@name which is contrary to the established convention. For example,
we end up forcing vast majority of sysfs_get_dirent() users to do
sysfs_get_dirent(parent, NULL, name), which is silly and error-prone
especially as @ns and @name may be interchanged without causing
compilation warning.

This renames sysfs_get_dirent() to sysfs_get_dirent_ns() and swap the
positions of @name and @ns, and sysfs_get_dirent() is now a wrapper
around sysfs_get_dirent_ns(). This makes confusions a lot less
likely.

There are other interfaces which take @ns before @name. They'll be
updated by following patches.

This patch doesn't introduce any functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kay Sievers <kay@vrfy.org>
---
drivers/gpio/gpiolib.c | 2 +-
drivers/md/bitmap.c | 4 ++--
drivers/md/md.c | 2 +-
drivers/md/md.h | 2 +-
fs/sysfs/dir.c | 9 +++++----
fs/sysfs/file.c | 4 ++--
fs/sysfs/group.c | 10 +++++-----
fs/sysfs/symlink.c | 2 +-
fs/sysfs/sysfs.h | 3 ---
include/linux/sysfs.h | 19 ++++++++++++-------
10 files changed, 30 insertions(+), 27 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 86ef346..a094356 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -408,7 +408,7 @@ static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev,
IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;

if (!value_sd) {
- value_sd = sysfs_get_dirent(dev->kobj.sd, NULL, "value");
+ value_sd = sysfs_get_dirent(dev->kobj.sd, "value");
if (!value_sd) {
ret = -ENODEV;
goto err_out;
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index a7fd821..12dc29b 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1654,9 +1654,9 @@ int bitmap_create(struct mddev *mddev)
bitmap->mddev = mddev;

if (mddev->kobj.sd)
- bm = sysfs_get_dirent(mddev->kobj.sd, NULL, "bitmap");
+ bm = sysfs_get_dirent(mddev->kobj.sd, "bitmap");
if (bm) {
- bitmap->sysfs_can_clear = sysfs_get_dirent(bm, NULL, "can_clear");
+ bitmap->sysfs_can_clear = sysfs_get_dirent(bm, "can_clear");
sysfs_put(bm);
} else
bitmap->sysfs_can_clear = NULL;
diff --git a/drivers/md/md.c b/drivers/md/md.c
index adf4d7e..8a0d762 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3555,7 +3555,7 @@ level_store(struct mddev *mddev, const char *buf, size_t len)
printk(KERN_WARNING
"md: cannot register extra attributes for %s\n",
mdname(mddev));
- mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, NULL, "sync_action");
+ mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, "sync_action");
}
if (mddev->pers->sync_request != NULL &&
pers->sync_request == NULL) {
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 608050c..b0051f2 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -501,7 +501,7 @@ extern struct attribute_group md_bitmap_group;
static inline struct sysfs_dirent *sysfs_get_dirent_safe(struct sysfs_dirent *sd, char *name)
{
if (sd)
- return sysfs_get_dirent(sd, NULL, name);
+ return sysfs_get_dirent(sd, name);
return sd;
}
static inline void sysfs_notify_dirent_safe(struct sysfs_dirent *sd)
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 1dfb4aa..3dacce0 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -630,9 +630,10 @@ struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
}

/**
- * sysfs_get_dirent - find and get sysfs_dirent with the given name
+ * sysfs_get_dirent_ns - find and get sysfs_dirent with the given name
* @parent_sd: sysfs_dirent to search under
* @name: name to look for
+ * @ns: the namespace tag to use
*
* Look for sysfs_dirent with name @name under @parent_sd and get
* it if found.
@@ -643,9 +644,9 @@ struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
* RETURNS:
* Pointer to sysfs_dirent if found, NULL if not.
*/
-struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
- const void *ns,
- const unsigned char *name)
+struct sysfs_dirent *sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd,
+ const unsigned char *name,
+ const void *ns)
{
struct sysfs_dirent *sd;

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index e784340..0f3214a 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -563,7 +563,7 @@ int sysfs_add_file_to_group(struct kobject *kobj,
int error;

if (group)
- dir_sd = sysfs_get_dirent(kobj->sd, NULL, group);
+ dir_sd = sysfs_get_dirent(kobj->sd, group);
else
dir_sd = sysfs_get(kobj->sd);

@@ -645,7 +645,7 @@ void sysfs_remove_file_from_group(struct kobject *kobj,
struct sysfs_dirent *dir_sd;

if (group)
- dir_sd = sysfs_get_dirent(kobj->sd, NULL, group);
+ dir_sd = sysfs_get_dirent(kobj->sd, group);
else
dir_sd = sysfs_get(kobj->sd);
if (dir_sd) {
diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c
index 25c78f2..2110215 100644
--- a/fs/sysfs/group.c
+++ b/fs/sysfs/group.c
@@ -207,7 +207,7 @@ void sysfs_remove_group(struct kobject *kobj,
struct sysfs_dirent *sd;

if (grp->name) {
- sd = sysfs_get_dirent(dir_sd, NULL, grp->name);
+ sd = sysfs_get_dirent(dir_sd, grp->name);
if (!sd) {
WARN(!sd, KERN_WARNING
"sysfs group %p not found for kobject '%s'\n",
@@ -262,7 +262,7 @@ int sysfs_merge_group(struct kobject *kobj,
struct attribute *const *attr;
int i;

- dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name);
+ dir_sd = sysfs_get_dirent(kobj->sd, grp->name);
if (!dir_sd)
return -ENOENT;

@@ -289,7 +289,7 @@ void sysfs_unmerge_group(struct kobject *kobj,
struct sysfs_dirent *dir_sd;
struct attribute *const *attr;

- dir_sd = sysfs_get_dirent(kobj->sd, NULL, grp->name);
+ dir_sd = sysfs_get_dirent(kobj->sd, grp->name);
if (dir_sd) {
for (attr = grp->attrs; *attr; ++attr)
sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name);
@@ -311,7 +311,7 @@ int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
struct sysfs_dirent *dir_sd;
int error = 0;

- dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name);
+ dir_sd = sysfs_get_dirent(kobj->sd, group_name);
if (!dir_sd)
return -ENOENT;

@@ -333,7 +333,7 @@ void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
{
struct sysfs_dirent *dir_sd;

- dir_sd = sysfs_get_dirent(kobj->sd, NULL, group_name);
+ dir_sd = sysfs_get_dirent(kobj->sd, group_name);
if (dir_sd) {
sysfs_hash_and_remove(dir_sd, NULL, link_name);
sysfs_put(dir_sd);
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 7d981ce..c96b31a 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -191,7 +191,7 @@ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *targ,
old_ns = targ->sd->s_ns;

result = -ENOENT;
- sd = sysfs_get_dirent(parent_sd, old_ns, old);
+ sd = sysfs_get_dirent_ns(parent_sd, old, old_ns);
if (!sd)
goto out;

diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 7664d1b..6faacaf 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -164,9 +164,6 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
const void *ns,
const unsigned char *name);
-struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
- const void *ns,
- const unsigned char *name);
struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);

void release_sysfs_dirent(struct sysfs_dirent *sd);
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index c792f73..6695040 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -245,9 +245,9 @@ void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,

void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
void sysfs_notify_dirent(struct sysfs_dirent *sd);
-struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
- const void *ns,
- const unsigned char *name);
+struct sysfs_dirent *sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd,
+ const unsigned char *name,
+ const void *ns);
struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
void sysfs_put(struct sysfs_dirent *sd);

@@ -422,10 +422,9 @@ static inline void sysfs_notify(struct kobject *kobj, const char *dir,
static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
{
}
-static inline
-struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
- const void *ns,
- const unsigned char *name)
+static inline struct sysfs_dirent *
+sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd, const unsigned char *name,
+ const void *ns)
{
return NULL;
}
@@ -462,4 +461,10 @@ static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target
return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
}

+static inline struct sysfs_dirent *
+sysfs_get_dirent(struct sysfs_dirent *parent_sd, const unsigned char *name)
+{
+ return sysfs_get_dirent_ns(parent_sd, name, NULL);
+}
+
#endif /* _SYSFS_H_ */
--
1.8.3.1