fsnotify: change locking order

[~andy/linux] / include / linux / fsnotify_backend.h

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 63d966d5c2ea7a382c2f42cc664c7804dec86f73..1af2f6a722c0defa7b3f9d88f03bfb45a507a011 100644 (file)
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -88,9 +88,10 @@ struct fsnotify_event_private_data;
  *             if the group is interested in this event.
  * handle_event - main call for a group to handle an fs event
  * free_group_priv - called when a group refcnt hits 0 to clean up the private union
- * freeing-mark - this means that a mark has been flagged to die when everything
- *             finishes using it.  The function is supplied with what must be a
- *             valid group and inode to use to clean up.
+ * freeing_mark - called when a mark is being destroyed for some reason.  The group
+ *             MUST be holding a reference on each mark and that reference must be
+ *             dropped in this function.  inotify uses this function to send
+ *             userspace messages that marks have been removed.
  */
 struct fsnotify_ops {
        bool (*should_send_event)(struct fsnotify_group *group, struct inode *inode,
@@ -141,7 +142,7 @@ struct fsnotify_group {
        unsigned int priority;
 
        /* stores all fastpath marks assoc with this group so they can be cleaned on unregister */
-       spinlock_t mark_lock;           /* protect marks_list */
+       struct mutex mark_mutex;        /* protect marks_list */
        atomic_t num_marks;             /* 1 for each mark and 1 for not being
                                         * past the point of no return when freeing
                                         * a group */
@@ -287,7 +288,6 @@ struct fsnotify_mark {
                struct fsnotify_inode_mark i;
                struct fsnotify_vfsmount_mark m;
        };
-       struct list_head free_g_list;   /* tmp list used when freeing this mark */
        __u32 ignored_mask;             /* events types to ignore */
 #define FSNOTIFY_MARK_FLAG_INODE               0x01
 #define FSNOTIFY_MARK_FLAG_VFSMOUNT            0x02
@@ -360,11 +360,14 @@ static inline void __fsnotify_d_instantiate(struct dentry *dentry, struct inode
 
 /* called from fsnotify listeners, such as fanotify or dnotify */
 
-/* get a reference to an existing or create a new group */
+/* create a new group */
 extern struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops);
+/* get reference to a group */
+extern void fsnotify_get_group(struct fsnotify_group *group);
 /* drop reference on a group from fsnotify_alloc_group */
 extern void fsnotify_put_group(struct fsnotify_group *group);
-
+/* destroy group */
+extern void fsnotify_destroy_group(struct fsnotify_group *group);
 /* take a reference to an event */
 extern void fsnotify_get_event(struct fsnotify_event *event);
 extern void fsnotify_put_event(struct fsnotify_event *event);
@@ -405,8 +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);
-/* given a mark, flag it to be freed when all references are dropped */
-extern void fsnotify_destroy_mark(struct fsnotify_mark *mark);
+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 */