1 files changed, 55 insertions, 48 deletions

diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index 61f4c5fa34c7..05506d60131c 100644
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -109,6 +109,23 @@ void fsnotify_get_mark(struct fsnotify_mark *mark)
 	refcount_inc(&mark->refcnt);
 }
 
+static __u32 *fsnotify_conn_mask_p(struct fsnotify_mark_connector *conn)
+{
+	if (conn->type == FSNOTIFY_OBJ_TYPE_INODE)
+		return &fsnotify_conn_inode(conn)->i_fsnotify_mask;
+	else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT)
+		return &fsnotify_conn_mount(conn)->mnt_fsnotify_mask;
+	return NULL;
+}
+
+__u32 fsnotify_conn_mask(struct fsnotify_mark_connector *conn)
+{
+	if (WARN_ON(!fsnotify_valid_obj_type(conn->type)))
+		return 0;
+
+	return *fsnotify_conn_mask_p(conn);
+}
+
 static void __fsnotify_recalc_mask(struct fsnotify_mark_connector *conn)
 {
 	u32 new_mask = 0;
@@ -119,15 +136,15 @@ static void __fsnotify_recalc_mask(struct fsnotify_mark_connector *conn)
 		if (mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED)
 			new_mask |= mark->mask;
 	}
-	if (conn->type == FSNOTIFY_OBJ_TYPE_INODE)
-		conn->inode->i_fsnotify_mask = new_mask;
-	else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT)
-		real_mount(conn->mnt)->mnt_fsnotify_mask = new_mask;
+	if (WARN_ON(!fsnotify_valid_obj_type(conn->type)))
+		return;
+
+	*fsnotify_conn_mask_p(conn) = new_mask;
 }
 
 /*
  * Calculate mask of events for a list of marks. The caller must make sure
- * connector and connector->inode cannot disappear under us.  Callers achieve
+ * connector and connector->obj cannot disappear under us.  Callers achieve
  * this by holding a mark->lock or mark->group->mark_mutex for a mark on this
  * list.
  */
@@ -140,7 +157,8 @@ void fsnotify_recalc_mask(struct fsnotify_mark_connector *conn)
 	__fsnotify_recalc_mask(conn);
 	spin_unlock(&conn->lock);
 	if (conn->type == FSNOTIFY_OBJ_TYPE_INODE)
-		__fsnotify_update_child_dentry_flags(conn->inode);
+		__fsnotify_update_child_dentry_flags(
+					fsnotify_conn_inode(conn));
 }
 
 /* Free all connectors queued for freeing once SRCU period ends */
@@ -166,20 +184,20 @@ static struct inode *fsnotify_detach_connector_from_object(
 {
 	struct inode *inode = NULL;
 
+	if (conn->type == FSNOTIFY_OBJ_TYPE_DETACHED)
+		return NULL;
+
 	if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) {
-		inode = conn->inode;
-		rcu_assign_pointer(inode->i_fsnotify_marks, NULL);
+		inode = fsnotify_conn_inode(conn);
 		inode->i_fsnotify_mask = 0;
-		conn->inode = NULL;
-		conn->type = FSNOTIFY_OBJ_TYPE_DETACHED;
 	} else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
-		rcu_assign_pointer(real_mount(conn->mnt)->mnt_fsnotify_marks,
-				   NULL);
-		real_mount(conn->mnt)->mnt_fsnotify_mask = 0;
-		conn->mnt = NULL;
-		conn->type = FSNOTIFY_OBJ_TYPE_DETACHED;
+		fsnotify_conn_mount(conn)->mnt_fsnotify_mask = 0;
 	}
 
+	rcu_assign_pointer(*(conn->obj), NULL);
+	conn->obj = NULL;
+	conn->type = FSNOTIFY_OBJ_TYPE_DETACHED;
+
 	return inode;
 }
 
@@ -436,11 +454,10 @@ int fsnotify_compare_groups(struct fsnotify_group *a, struct fsnotify_group *b)
 	return -1;
 }
 
-static int fsnotify_attach_connector_to_object(
-				struct fsnotify_mark_connector __rcu **connp,
-				struct inode *inode,
-				struct vfsmount *mnt)
+static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
+					       unsigned int type)
 {
+	struct inode *inode = NULL;
 	struct fsnotify_mark_connector *conn;
 
 	conn = kmem_cache_alloc(fsnotify_mark_connector_cachep, GFP_KERNEL);
@@ -448,13 +465,10 @@ static int fsnotify_attach_connector_to_object(
 		return -ENOMEM;
 	spin_lock_init(&conn->lock);
 	INIT_HLIST_HEAD(&conn->list);
-	if (inode) {
-		conn->type = FSNOTIFY_OBJ_TYPE_INODE;
-		conn->inode = igrab(inode);
-	} else {
-		conn->type = FSNOTIFY_OBJ_TYPE_VFSMOUNT;
-		conn->mnt = mnt;
-	}
+	conn->type = type;
+	conn->obj = connp;
+	if (conn->type == FSNOTIFY_OBJ_TYPE_INODE)
+		inode = igrab(fsnotify_conn_inode(conn));
 	/*
 	 * cmpxchg() provides the barrier so that readers of *connp can see
 	 * only initialized structure
@@ -476,7 +490,7 @@ static int fsnotify_attach_connector_to_object(
  * they are sure list cannot go away under them.
  */
 static struct fsnotify_mark_connector *fsnotify_grab_connector(
-				struct fsnotify_mark_connector __rcu **connp)
+						fsnotify_connp_t *connp)
 {
 	struct fsnotify_mark_connector *conn;
 	int idx;
@@ -503,27 +517,22 @@ out:
  * priority, highest number first, and then by the group's location in memory.
  */
 static int fsnotify_add_mark_list(struct fsnotify_mark *mark,
-				  struct inode *inode, struct vfsmount *mnt,
+				  fsnotify_connp_t *connp, unsigned int type,
 				  int allow_dups)
 {
 	struct fsnotify_mark *lmark, *last = NULL;
 	struct fsnotify_mark_connector *conn;
-	struct fsnotify_mark_connector __rcu **connp;
 	int cmp;
 	int err = 0;
 
-	if (WARN_ON(!inode && !mnt))
+	if (WARN_ON(!fsnotify_valid_obj_type(type)))
 		return -EINVAL;
-	if (inode)
-		connp = &inode->i_fsnotify_marks;
-	else
-		connp = &real_mount(mnt)->mnt_fsnotify_marks;
 restart:
 	spin_lock(&mark->lock);
 	conn = fsnotify_grab_connector(connp);
 	if (!conn) {
 		spin_unlock(&mark->lock);
-		err = fsnotify_attach_connector_to_object(connp, inode, mnt);
+		err = fsnotify_attach_connector_to_object(connp, type);
 		if (err)
 			return err;
 		goto restart;
@@ -569,14 +578,13 @@ out_err:
  * These marks may be used for the fsnotify backend to determine which
  * event types should be delivered to which group.
  */
-int fsnotify_add_mark_locked(struct fsnotify_mark *mark, struct inode *inode,
-			     struct vfsmount *mnt, int allow_dups)
+int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
+			     fsnotify_connp_t *connp, unsigned int type,
+			     int allow_dups)
 {
 	struct fsnotify_group *group = mark->group;
 	int ret = 0;
 
-	BUG_ON(inode && mnt);
-	BUG_ON(!inode && !mnt);
 	BUG_ON(!mutex_is_locked(&group->mark_mutex));
 
 	/*
@@ -593,7 +601,7 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark, struct inode *inode,
 	fsnotify_get_mark(mark); /* for g_list */
 	spin_unlock(&mark->lock);
 
-	ret = fsnotify_add_mark_list(mark, inode, mnt, allow_dups);
+	ret = fsnotify_add_mark_list(mark, connp, type, allow_dups);
 	if (ret)
 		goto err;
 
@@ -613,14 +621,14 @@ err:
 	return ret;
 }
 
-int fsnotify_add_mark(struct fsnotify_mark *mark, struct inode *inode,
-		      struct vfsmount *mnt, int allow_dups)
+int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp,
+		      unsigned int type, int allow_dups)
 {
 	int ret;
 	struct fsnotify_group *group = mark->group;
 
 	mutex_lock(&group->mark_mutex);
-	ret = fsnotify_add_mark_locked(mark, inode, mnt, allow_dups);
+	ret = fsnotify_add_mark_locked(mark, connp, type, allow_dups);
 	mutex_unlock(&group->mark_mutex);
 	return ret;
 }
@@ -629,9 +637,8 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, struct inode *inode,
  * Given a list of marks, find the mark associated with given group. If found
  * take a reference to that mark and return it, else return NULL.
  */
-struct fsnotify_mark *fsnotify_find_mark(
-				struct fsnotify_mark_connector __rcu **connp,
-				struct fsnotify_group *group)
+struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp,
+					 struct fsnotify_group *group)
 {
 	struct fsnotify_mark_connector *conn;
 	struct fsnotify_mark *mark;
@@ -697,8 +704,8 @@ clear:
 	}
 }
 
-/* Destroy all marks attached to inode / vfsmount */
-void fsnotify_destroy_marks(struct fsnotify_mark_connector __rcu **connp)
+/* Destroy all marks attached to an object via connector */
+void fsnotify_destroy_marks(fsnotify_connp_t *connp)
 {
 	struct fsnotify_mark_connector *conn;
 	struct fsnotify_mark *mark, *old_mark = NULL;