fsnotify: introduce locked versions of fsnotify_add_mark() and fsnotify_remove_mark()

This patch introduces fsnotify_add_mark_locked() and fsnotify_remove_mark_locked()
which are essentially the same as fsnotify_add_mark() and fsnotify_remove_mark() but
assume that the caller has already taken the groups mark mutex.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
This commit is contained in:
Lino Sanfilippo 2011-06-14 17:29:52 +02:00 committed by Eric Paris
parent e2a29943e9
commit d5a335b845
2 changed files with 34 additions and 12 deletions

View File

@ -121,18 +121,18 @@ void fsnotify_put_mark(struct fsnotify_mark *mark)
* The caller had better be holding a reference to this mark so we don't actually
* do the final put under the mark->lock
*/
void fsnotify_destroy_mark(struct fsnotify_mark *mark,
struct fsnotify_group *group)
void fsnotify_destroy_mark_locked(struct fsnotify_mark *mark,
struct fsnotify_group *group)
{
struct inode *inode = NULL;
mutex_lock(&group->mark_mutex);
BUG_ON(!mutex_is_locked(&group->mark_mutex));
spin_lock(&mark->lock);
/* something else already called this function on this mark */
if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE)) {
spin_unlock(&mark->lock);
mutex_unlock(&group->mark_mutex);
return;
}
@ -149,6 +149,8 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark,
list_del_init(&mark->g_list);
spin_unlock(&mark->lock);
/* release lock temporarily */
mutex_unlock(&group->mark_mutex);
spin_lock(&destroy_lock);
@ -184,6 +186,16 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark,
*/
atomic_dec(&group->num_marks);
mutex_lock(&group->mark_mutex);
}
void fsnotify_destroy_mark(struct fsnotify_mark *mark,
struct fsnotify_group *group)
{
mutex_lock(&group->mark_mutex);
fsnotify_destroy_mark_locked(mark, group);
mutex_unlock(&group->mark_mutex);
}
void fsnotify_set_mark_mask_locked(struct fsnotify_mark *mark, __u32 mask)
@ -208,14 +220,15 @@ void fsnotify_set_mark_ignored_mask_locked(struct fsnotify_mark *mark, __u32 mas
* These marks may be used for the fsnotify backend to determine which
* event types should be delivered to which group.
*/
int fsnotify_add_mark(struct fsnotify_mark *mark,
struct fsnotify_group *group, struct inode *inode,
struct vfsmount *mnt, int allow_dups)
int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
struct fsnotify_group *group, struct inode *inode,
struct vfsmount *mnt, int allow_dups)
{
int ret = 0;
BUG_ON(inode && mnt);
BUG_ON(!inode && !mnt);
BUG_ON(!mutex_is_locked(&group->mark_mutex));
/*
* LOCKING ORDER!!!!
@ -223,8 +236,6 @@ int fsnotify_add_mark(struct fsnotify_mark *mark,
* mark->lock
* inode->i_lock
*/
mutex_lock(&group->mark_mutex);
spin_lock(&mark->lock);
mark->flags |= FSNOTIFY_MARK_FLAG_ALIVE;
@ -250,8 +261,6 @@ int fsnotify_add_mark(struct fsnotify_mark *mark,
fsnotify_set_mark_mask_locked(mark, mark->mask);
spin_unlock(&mark->lock);
mutex_unlock(&group->mark_mutex);
if (inode)
__fsnotify_update_child_dentry_flags(inode);
@ -264,7 +273,6 @@ err:
atomic_dec(&group->num_marks);
spin_unlock(&mark->lock);
mutex_unlock(&group->mark_mutex);
spin_lock(&destroy_lock);
list_add(&mark->destroy_list, &destroy_list);
@ -274,6 +282,16 @@ err:
return ret;
}
int fsnotify_add_mark(struct fsnotify_mark *mark, struct fsnotify_group *group,
struct inode *inode, struct vfsmount *mnt, int allow_dups)
{
int ret;
mutex_lock(&group->mark_mutex);
ret = fsnotify_add_mark_locked(mark, group, inode, mnt, allow_dups);
mutex_unlock(&group->mark_mutex);
return ret;
}
/*
* clear any marks in a group in which mark->flags & flags is true
*/

View File

@ -408,9 +408,13 @@ extern void fsnotify_set_mark_mask_locked(struct fsnotify_mark *mark, __u32 mask
/* attach the mark to both the group and the inode */
extern int fsnotify_add_mark(struct fsnotify_mark *mark, struct fsnotify_group *group,
struct inode *inode, struct vfsmount *mnt, int allow_dups);
extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark, struct fsnotify_group *group,
struct inode *inode, struct vfsmount *mnt, int allow_dups);
/* given a group and a mark, flag mark to be freed when all references are dropped */
extern void fsnotify_destroy_mark(struct fsnotify_mark *mark,
struct fsnotify_group *group);
extern void fsnotify_destroy_mark_locked(struct fsnotify_mark *mark,
struct fsnotify_group *group);
/* run all the marks in a group, and clear all of the vfsmount marks */
extern void fsnotify_clear_vfsmount_marks_by_group(struct fsnotify_group *group);
/* run all the marks in a group, and clear all of the inode marks */