New function blk_req_append_bio

ll_back_merge_fn is currently exported to SCSI where is it used,
together with blk_rq_bio_prep, in exactly the same way these
functions are used in __blk_rq_map_user.

So move the common code into a new function (blk_rq_append_bio), and
don't export ll_back_merge_fn any longer.

Signed-off-by: Neil Brown <neilb@suse.de>

diff .prev/block/ll_rw_blk.c ./block/ll_rw_blk.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 1 insertions, 10 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index a417a6ff9f97..59b398530295 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -263,16 +263,7 @@ static int scsi_merge_bio(struct request *rq, struct bio *bio)
                 bio->bi_rw |= (1 << BIO_RW);
         blk_queue_bounce(q, &bio);
 
-        if (!rq->bio)
-                blk_rq_bio_prep(q, rq, bio);
-        else if (!ll_back_merge_fn(q, rq, bio))
-                return -EINVAL;
-        else {
-                rq->biotail->bi_next = bio;
-                rq->biotail = bio;
-        }
-
-        return 0;
+        return blk_rq_append_bio(q, rq, bio);
 }
 
 static int scsi_bi_endio(struct bio *bio, unsigned int bytes_done, int error)