diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4a99b76..67339bc 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -560,6 +560,8 @@
 extern void blk_queue_activity_fn(request_queue_t *, activity_fn *, void *);
 extern struct request *blk_rq_map_user(request_queue_t *, int, void __user *, unsigned int);
 extern int blk_rq_unmap_user(struct request *, struct bio *, unsigned int);
+extern struct request *blk_rq_map_kern(request_queue_t *, int, void *,
+					unsigned int, unsigned int);
 extern int blk_execute_rq(request_queue_t *, struct gendisk *, struct request *);
 
 static inline request_queue_t *bdev_get_queue(struct block_device *bdev)