diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 358ac42..9c25492 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -899,6 +899,13 @@
 	return q ? q->dma_alignment : 511;
 }
 
+static inline int blk_rq_aligned(struct request_queue *q, void *addr,
+				 unsigned int len)
+{
+	unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
+	return !((unsigned long)addr & alignment) && !(len & alignment);
+}
+
 /* assumes size > 256 */
 static inline unsigned int blksize_bits(unsigned int size)
 {