From 746edb7ae8a1abdd39be2b28c03aa073183340db Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 30 Mar 2010 11:31:28 -0700 Subject: [PATCH] sysfs: Implement sysfs_delete_link When removing a symlink sysfs_remove_link does not provide enough information to figure out which tagged directory the symlink falls in. So I need sysfs_delete_link which is passed the target of the symlink to delete. sysfs_rename_link is updated to call sysfs_delete_link instead of sysfs_remove_link as we have all of the information necessary and the callers are interesting. Both of these functions now have enough information to find a symlink in a tagged directory. The only restriction is that they must be called before the target kobject is renamed or deleted. If they are called later I loose track of which tag the target kobject was marked with and can no longer find the old symlink to remove it. This patch was split from an earlier patch. Signed-off-by: Eric W. Biederman Signed-off-by: Benjamin Thery Signed-off-by: Daniel Lezcano Acked-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/symlink.c | 20 ++++++++++++++++++++ include/linux/sysfs.h | 8 ++++++++ 2 files changed, 28 insertions(+) diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index b6ebdaa00f37..f71246bebfe4 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -108,6 +108,26 @@ int sysfs_create_link_nowarn(struct kobject *kobj, struct kobject *target, return sysfs_do_create_link(kobj, target, name, 0); } +/** + * sysfs_delete_link - remove symlink in object's directory. + * @kobj: object we're acting for. + * @targ: object we're pointing to. + * @name: name of the symlink to remove. + * + * Unlike sysfs_remove_link sysfs_delete_link has enough information + * to successfully delete symlinks in tagged directories. + */ +void sysfs_delete_link(struct kobject *kobj, struct kobject *targ, + const char *name) +{ + const void *ns = NULL; + spin_lock(&sysfs_assoc_lock); + if (targ->sd) + ns = targ->sd->s_ns; + spin_unlock(&sysfs_assoc_lock); + sysfs_hash_and_remove(kobj->sd, ns, name); +} + /** * sysfs_remove_link - remove symlink in object's directory. * @kobj: object we're acting for. diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 1885d21b0c80..976c4664b216 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -155,6 +155,9 @@ 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); +void sysfs_delete_link(struct kobject *dir, struct kobject *targ, + const char *name); + int __must_check sysfs_create_group(struct kobject *kobj, const struct attribute_group *grp); int sysfs_update_group(struct kobject *kobj, @@ -269,6 +272,11 @@ static inline int sysfs_rename_link(struct kobject *k, struct kobject *t, return 0; } +static inline void sysfs_delete_link(struct kobject *k, struct kobject *t, + const char *name) +{ +} + static inline int sysfs_create_group(struct kobject *kobj, const struct attribute_group *grp) {