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authorPatrick McHardy <kaber@trash.net>2013-03-31 18:10:34 +0200
committerPatrick McHardy <kaber@trash.net>2013-03-31 18:10:34 +0200
commit70711d223510ba1773cfe1d7770a56141c815ff8 (patch)
tree4a71f38a3a554ddecaa31b7d8c6bc49b7d1705b4 /fs/notify/group.c
parentd53b4ed072d9779cdf53582c46436dec06d0961f (diff)
parent19f949f52599ba7c3f67a5897ac6be14bfcb1200 (diff)
Merge tag 'v3.8' of /home/kaber/src/repos/linux
Linux 3.8 Signed-off-by: Patrick McHardy <kaber@trash.net> Conflicts: include/linux/Kbuild include/linux/netlink.h
Diffstat (limited to 'fs/notify/group.c')
-rw-r--r--fs/notify/group.c47
1 files changed, 27 insertions, 20 deletions
diff --git a/fs/notify/group.c b/fs/notify/group.c
index 63fc294a469..bd2625bd88b 100644
--- a/fs/notify/group.c
+++ b/fs/notify/group.c
@@ -33,9 +33,6 @@
*/
void fsnotify_final_destroy_group(struct fsnotify_group *group)
{
- /* clear the notification queue of all events */
- fsnotify_flush_notify(group);
-
if (group->ops->free_group_priv)
group->ops->free_group_priv(group);
@@ -43,23 +40,30 @@ void fsnotify_final_destroy_group(struct fsnotify_group *group)
}
/*
- * Trying to get rid of a group. We need to first get rid of any outstanding
- * allocations and then free the group. Remember that fsnotify_clear_marks_by_group
- * could miss marks that are being freed by inode and those marks could still
- * hold a reference to this group (via group->num_marks) If we get into that
- * situtation, the fsnotify_final_destroy_group will get called when that final
- * mark is freed.
+ * Trying to get rid of a group. Remove all marks, flush all events and release
+ * the group reference.
+ * Note that another thread calling fsnotify_clear_marks_by_group() may still
+ * hold a ref to the group.
*/
-static void fsnotify_destroy_group(struct fsnotify_group *group)
+void fsnotify_destroy_group(struct fsnotify_group *group)
{
/* clear all inode marks for this group */
fsnotify_clear_marks_by_group(group);
synchronize_srcu(&fsnotify_mark_srcu);
- /* past the point of no return, matches the initial value of 1 */
- if (atomic_dec_and_test(&group->num_marks))
- fsnotify_final_destroy_group(group);
+ /* clear the notification queue of all events */
+ fsnotify_flush_notify(group);
+
+ fsnotify_put_group(group);
+}
+
+/*
+ * Get reference to a group.
+ */
+void fsnotify_get_group(struct fsnotify_group *group)
+{
+ atomic_inc(&group->refcnt);
}
/*
@@ -68,7 +72,7 @@ static void fsnotify_destroy_group(struct fsnotify_group *group)
void fsnotify_put_group(struct fsnotify_group *group)
{
if (atomic_dec_and_test(&group->refcnt))
- fsnotify_destroy_group(group);
+ fsnotify_final_destroy_group(group);
}
/*
@@ -84,21 +88,24 @@ struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops)
/* set to 0 when there a no external references to this group */
atomic_set(&group->refcnt, 1);
- /*
- * hits 0 when there are no external references AND no marks for
- * this group
- */
- atomic_set(&group->num_marks, 1);
+ atomic_set(&group->num_marks, 0);
mutex_init(&group->notification_mutex);
INIT_LIST_HEAD(&group->notification_list);
init_waitqueue_head(&group->notification_waitq);
group->max_events = UINT_MAX;
- spin_lock_init(&group->mark_lock);
+ mutex_init(&group->mark_mutex);
INIT_LIST_HEAD(&group->marks_list);
group->ops = ops;
return group;
}
+
+int fsnotify_fasync(int fd, struct file *file, int on)
+{
+ struct fsnotify_group *group = file->private_data;
+
+ return fasync_helper(fd, file, on, &group->fsn_fa) >= 0 ? 0 : -EIO;
+}