sysfs: Implement sysfs_rename_link

Because of rename ordering problems we occassionally give false
warnings about invalid sysfs operations.  So using sysfs_rename
create a sysfs_rename_link function that doesn't need strange
workarounds.

Cc: Benjamin Thery <benjamin.thery@bull.net>
Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Eric W. Biederman 2010-02-12 19:22:25 -08:00 committed by Greg Kroah-Hartman
parent 19c38b632d
commit 7cb32942d9
2 changed files with 47 additions and 0 deletions

View File

@ -123,6 +123,44 @@ void sysfs_remove_link(struct kobject * kobj, const char * name)
sysfs_hash_and_remove(parent_sd, name);
}
/**
* sysfs_rename_link - rename symlink in object's directory.
* @kobj: object we're acting for.
* @targ: object we're pointing to.
* @old: previous name of the symlink.
* @new: new name of the symlink.
*
* A helper function for the common rename symlink idiom.
*/
int sysfs_rename_link(struct kobject *kobj, struct kobject *targ,
const char *old, const char *new)
{
struct sysfs_dirent *parent_sd, *sd = NULL;
int result;
if (!kobj)
parent_sd = &sysfs_root;
else
parent_sd = kobj->sd;
result = -ENOENT;
sd = sysfs_get_dirent(parent_sd, old);
if (!sd)
goto out;
result = -EINVAL;
if (sysfs_type(sd) != SYSFS_KOBJ_LINK)
goto out;
if (sd->s_symlink.target_sd->s_dir.kobj != targ)
goto out;
result = sysfs_rename(sd, parent_sd, new);
out:
sysfs_put(sd);
return result;
}
static int sysfs_get_target_path(struct sysfs_dirent *parent_sd,
struct sysfs_dirent *target_sd, char *path)
{

View File

@ -151,6 +151,9 @@ int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
const char *name);
void sysfs_remove_link(struct kobject *kobj, const char *name);
int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
const char *old_name, const char *new_name);
int __must_check sysfs_create_group(struct kobject *kobj,
const struct attribute_group *grp);
int sysfs_update_group(struct kobject *kobj,
@ -255,6 +258,12 @@ static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
{
}
static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
const char *old_name, const char *new_name)
{
return 0;
}
static inline int sysfs_create_group(struct kobject *kobj,
const struct attribute_group *grp)
{