Merge branch 'for-upstream' of github.com:jdike/zfs into for-upstream

module/zfs/sa.c

@@ -231,6 +231,9 @@ sa_cache_destructor(void *buf, void *unused)
 	mutex_destroy(&hdl->sa_lock);
 }
 
+static kmutex_t sa_id_lock;
+static int sa_id = 0;
+
 void
 sa_cache_init(void)
 {
@@ -1017,8 +1020,12 @@ sa_setup(objset_t *os, uint64_t sa_obj, sa_attr_reg_t *reg_attrs, int count,
 	mutex_init(&sa->sa_lock, NULL, MUTEX_NOLOCKDEP, NULL);
 	sa->sa_master_obj = sa_obj;
 
+	mutex_enter(&sa_id_lock);
+	sa_id++;
+	mutex_exit(&sa_id_lock);
+
 	os->os_sa = sa;
-	mutex_enter(&sa->sa_lock);
+	mutex_enter_nested(&sa->sa_lock, sa_id);
 	mutex_exit(&os->os_user_ptr_lock);
 	avl_create(&sa->sa_layout_num_tree, layout_num_compare,
 	    sizeof (sa_lot_t), offsetof(sa_lot_t, lot_num_node));