diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index a905c49..55ef6ef 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -531,6 +531,11 @@
 
 #define rq_data_dir(rq)		((rq)->cmd_flags & 1)
 
+/*
+ * We regard a request as sync, if it's a READ or a SYNC write.
+ */
+#define rq_is_sync(rq)		(rq_data_dir((rq)) == READ || (rq)->cmd_flags & REQ_RW_SYNC)
+
 static inline int blk_queue_full(struct request_queue *q, int rw)
 {
 	if (rw == READ)