diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index 97a92fa..8d470b7 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -118,6 +118,7 @@
 
 #ifdef CONFIG_CGROUP_WRITEBACK
 	struct percpu_ref refcnt;	/* used only for !root wb's */
+	struct fprop_local_percpu memcg_completions;
 	struct cgroup_subsys_state *memcg_css; /* the associated memcg */
 	struct cgroup_subsys_state *blkcg_css; /* and blkcg */
 	struct list_head memcg_node;	/* anchored at memcg->cgwb_list */