Merge branches 'clk-renesas', 'clk-qcom', 'clk-mtk', 'clk-milbeaut' and 'clk-imx...

[sfrench/cifs-2.6.git] / fs / notify / mark.c

diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index d593d42695618f20f585e97ddb835305f7d72e00..22acb0a79b532eb7541e3f90a1b4753acd733518 100644 (file)
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -239,13 +239,13 @@ static void fsnotify_drop_object(unsigned int type, void *objp)
 
 void fsnotify_put_mark(struct fsnotify_mark *mark)
 {
-       struct fsnotify_mark_connector *conn;
+       struct fsnotify_mark_connector *conn = READ_ONCE(mark->connector);
        void *objp = NULL;
        unsigned int type = FSNOTIFY_OBJ_TYPE_DETACHED;
        bool free_conn = false;
 
        /* Catch marks that were actually never attached to object */
-       if (!mark->connector) {
+       if (!conn) {
                if (refcount_dec_and_test(&mark->refcnt))
                        fsnotify_final_mark_destroy(mark);
                return;
@@ -255,10 +255,9 @@ void fsnotify_put_mark(struct fsnotify_mark *mark)
         * We have to be careful so that traversals of obj_list under lock can
         * safely grab mark reference.
         */
-       if (!refcount_dec_and_lock(&mark->refcnt, &mark->connector->lock))
+       if (!refcount_dec_and_lock(&mark->refcnt, &conn->lock))
                return;
 
-       conn = mark->connector;
        hlist_del_init_rcu(&mark->obj_list);
        if (hlist_empty(&conn->list)) {
                objp = fsnotify_detach_connector_from_object(conn, &type);
@@ -266,7 +265,7 @@ void fsnotify_put_mark(struct fsnotify_mark *mark)
        } else {
                __fsnotify_recalc_mask(conn);
        }
-       mark->connector = NULL;
+       WRITE_ONCE(mark->connector, NULL);
        spin_unlock(&conn->lock);
 
        fsnotify_drop_object(type, objp);
@@ -620,7 +619,7 @@ restart:
        /* mark should be the last entry.  last is the current last entry */
        hlist_add_behind_rcu(&mark->obj_list, &last->obj_list);
 added:
-       mark->connector = conn;
+       WRITE_ONCE(mark->connector, conn);
 out_err:
        spin_unlock(&conn->lock);
        spin_unlock(&mark->lock);
@@ -808,6 +807,7 @@ void fsnotify_init_mark(struct fsnotify_mark *mark,
        refcount_set(&mark->refcnt, 1);
        fsnotify_get_group(group);
        mark->group = group;
+       WRITE_ONCE(mark->connector, NULL);
 }
 
 /*