diff --git a/block/blk.h b/block/blk.h
index 686712e..9d22ec3 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -75,6 +75,10 @@ struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs,
 		gfp_t gfp_mask);
 void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs);
 
+bool bvec_try_merge_hw_page(struct request_queue *q, struct bio_vec *bv,
+		struct page *page, unsigned len, unsigned offset,
+		bool *same_page);
+
 static inline bool biovec_phys_mergeable(struct request_queue *q,
 		struct bio_vec *vec1, struct bio_vec *vec2)
 {