block: merge __bio_map_user_iov into bio_map_user_iov

And also remove the unused bdev argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

block/bio.c

@@ -1244,8 +1244,16 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
 	return ERR_PTR(ret);
 }
 
-static struct bio *__bio_map_user_iov(struct request_queue *q,
-				      struct block_device *bdev,
+/**
+ *	bio_map_user_iov - map user iovec into bio
+ *	@q:		the struct request_queue for the bio
+ *	@iter:		iovec iterator
+ *	@gfp_mask:	memory allocation flags
+ *
+ *	Map the user space address into a bio suitable for io to a block
+ *	device. Returns an error pointer in case of error.
+ */
+struct bio *bio_map_user_iov(struct request_queue *q,
 			     const struct iov_iter *iter,
 			     gfp_t gfp_mask)
 {
@@ -1343,8 +1351,15 @@ static struct bio *__bio_map_user_iov(struct request_queue *q,
 	if (iter->type & WRITE)
 		bio->bi_rw |= REQ_WRITE;
 
-	bio->bi_bdev = bdev;
 	bio->bi_flags |= (1 << BIO_USER_MAPPED);
+
+	/*
+	 * subtle -- if __bio_map_user() ended up bouncing a bio,
+	 * it would normally disappear when its bi_end_io is run.
+	 * however, we need it for the unmap, so grab an extra
+	 * reference to it
+	 */
+	bio_get(bio);
 	return bio;
 
  out_unmap:
@@ -1359,37 +1374,6 @@ static struct bio *__bio_map_user_iov(struct request_queue *q,
 	return ERR_PTR(ret);
 }
 
-/**
- *	bio_map_user_iov - map user iovec into bio
- *	@q:		the struct request_queue for the bio
- *	@bdev:		destination block device
- *	@iter:		iovec iterator
- *	@gfp_mask:	memory allocation flags
- *
- *	Map the user space address into a bio suitable for io to a block
- *	device. Returns an error pointer in case of error.
- */
-struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev,
-			     const struct iov_iter *iter,
-			     gfp_t gfp_mask)
-{
-	struct bio *bio;
-
-	bio = __bio_map_user_iov(q, bdev, iter, gfp_mask);
-	if (IS_ERR(bio))
-		return bio;
-
-	/*
-	 * subtle -- if __bio_map_user() ended up bouncing a bio,
-	 * it would normally disappear when its bi_end_io is run.
-	 * however, we need it for the unmap, so grab an extra
-	 * reference to it
-	 */
-	bio_get(bio);
-
-	return bio;
-}
-
 static void __bio_unmap_user(struct bio *bio)
 {
 	struct bio_vec *bvec;

block/blk-map.c

@@ -88,7 +88,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 	if (unaligned || (q->dma_pad_mask & iter->count) || map_data)
 		bio = bio_copy_user_iov(q, map_data, iter, gfp_mask);
 	else
-		bio = bio_map_user_iov(q, NULL, iter, gfp_mask);
+		bio = bio_map_user_iov(q, iter, gfp_mask);
 
 	if (IS_ERR(bio))
 		return PTR_ERR(bio);

include/linux/bio.h

@@ -430,7 +430,6 @@ extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
 extern int bio_get_nr_vecs(struct block_device *);
 struct rq_map_data;
 extern struct bio *bio_map_user_iov(struct request_queue *,
-				    struct block_device *,
 				    const struct iov_iter *, gfp_t);
 extern void bio_unmap_user(struct bio *);
 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,