diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 7a20425..c59b769 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -116,6 +116,7 @@
 extern void elv_completed_request(struct request_queue *, struct request *);
 extern int elv_set_request(struct request_queue *, struct request *, gfp_t);
 extern void elv_put_request(struct request_queue *, struct request *);
+extern void elv_drain_elevator(struct request_queue *);
 
 /*
  * io scheduler registration