diff options
Diffstat (limited to 'fs/notify/mark.c')
-rw-r--r-- | fs/notify/mark.c | 91 |
1 files changed, 50 insertions, 41 deletions
diff --git a/fs/notify/mark.c b/fs/notify/mark.c index f104d565b682..fc6b49bf7360 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -109,8 +109,11 @@ void fsnotify_get_mark(struct fsnotify_mark *mark) void fsnotify_put_mark(struct fsnotify_mark *mark) { - if (atomic_dec_and_test(&mark->refcnt)) + if (atomic_dec_and_test(&mark->refcnt)) { + if (mark->group) + fsnotify_put_group(mark->group); mark->free_mark(mark); + } } /* @@ -118,14 +121,14 @@ 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) +void fsnotify_destroy_mark_locked(struct fsnotify_mark *mark, + struct fsnotify_group *group) { - struct fsnotify_group *group; struct inode *inode = NULL; - spin_lock(&mark->lock); + BUG_ON(!mutex_is_locked(&group->mark_mutex)); - group = mark->group; + spin_lock(&mark->lock); /* something else already called this function on this mark */ if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE)) { @@ -135,8 +138,6 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark) mark->flags &= ~FSNOTIFY_MARK_FLAG_ALIVE; - spin_lock(&group->mark_lock); - if (mark->flags & FSNOTIFY_MARK_FLAG_INODE) { inode = mark->i.inode; fsnotify_destroy_inode_mark(mark); @@ -147,13 +148,22 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark) list_del_init(&mark->g_list); - spin_unlock(&group->mark_lock); spin_unlock(&mark->lock); + if (inode && (mark->flags & FSNOTIFY_MARK_FLAG_OBJECT_PINNED)) + iput(inode); + /* release lock temporarily */ + mutex_unlock(&group->mark_mutex); + spin_lock(&destroy_lock); list_add(&mark->destroy_list, &destroy_list); spin_unlock(&destroy_lock); wake_up(&destroy_waitq); + /* + * We don't necessarily have a ref on mark from caller so the above destroy + * may have actually freed it, unless this group provides a 'freeing_mark' + * function which must be holding a reference. + */ /* * Some groups like to know that marks are being freed. This is a @@ -175,21 +185,17 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark) * is just a lazy update (and could be a perf win...) */ - if (inode && (mark->flags & FSNOTIFY_MARK_FLAG_OBJECT_PINNED)) - iput(inode); + atomic_dec(&group->num_marks); - /* - * We don't necessarily have a ref on mark from caller so the above iput - * may have already destroyed it. Don't touch from now on. - */ + mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING); +} - /* - * it's possible that this group tried to destroy itself, but this - * this mark was simultaneously being freed by inode. If that's the - * case, we finish freeing the group here. - */ - if (unlikely(atomic_dec_and_test(&group->num_marks))) - fsnotify_final_destroy_group(group); +void fsnotify_destroy_mark(struct fsnotify_mark *mark, + struct fsnotify_group *group) +{ + mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING); + fsnotify_destroy_mark_locked(mark, group); + mutex_unlock(&group->mark_mutex); } void fsnotify_set_mark_mask_locked(struct fsnotify_mark *mark, __u32 mask) @@ -214,26 +220,26 @@ 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!!!! + * group->mark_mutex * mark->lock - * group->mark_lock * inode->i_lock */ spin_lock(&mark->lock); - spin_lock(&group->mark_lock); - mark->flags |= FSNOTIFY_MARK_FLAG_ALIVE; + fsnotify_get_group(group); mark->group = group; list_add(&mark->g_list, &group->marks_list); atomic_inc(&group->num_marks); @@ -251,11 +257,8 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, BUG(); } - spin_unlock(&group->mark_lock); - /* this will pin the object if appropriate */ fsnotify_set_mark_mask_locked(mark, mark->mask); - spin_unlock(&mark->lock); if (inode) @@ -265,10 +268,10 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, err: mark->flags &= ~FSNOTIFY_MARK_FLAG_ALIVE; list_del_init(&mark->g_list); + fsnotify_put_group(group); mark->group = NULL; atomic_dec(&group->num_marks); - spin_unlock(&group->mark_lock); spin_unlock(&mark->lock); spin_lock(&destroy_lock); @@ -279,6 +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 */ @@ -286,22 +299,16 @@ void fsnotify_clear_marks_by_group_flags(struct fsnotify_group *group, unsigned int flags) { struct fsnotify_mark *lmark, *mark; - LIST_HEAD(free_list); - spin_lock(&group->mark_lock); + mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING); list_for_each_entry_safe(mark, lmark, &group->marks_list, g_list) { if (mark->flags & flags) { - list_add(&mark->free_g_list, &free_list); - list_del_init(&mark->g_list); fsnotify_get_mark(mark); + fsnotify_destroy_mark_locked(mark, group); + fsnotify_put_mark(mark); } } - spin_unlock(&group->mark_lock); - - list_for_each_entry_safe(mark, lmark, &free_list, free_g_list) { - fsnotify_destroy_mark(mark); - fsnotify_put_mark(mark); - } + mutex_unlock(&group->mark_mutex); } /* @@ -317,6 +324,8 @@ void fsnotify_duplicate_mark(struct fsnotify_mark *new, struct fsnotify_mark *ol assert_spin_locked(&old->lock); new->i.inode = old->i.inode; new->m.mnt = old->m.mnt; + if (old->group) + fsnotify_get_group(old->group); new->group = old->group; new->mask = old->mask; new->free_mark = old->free_mark; |