dm: remove legacy code only needed before submit_bio recursion

Commit 8615cb65bd63 ("dm: remove useless loop in
__split_and_process_bio") showcased that we no longer loop.

Remove the bio_advance() in __split_and_process_bio() that was only
needed when looping was possible.

Similarly there is no need to advance the bio, using ci->sector
cursor, in __send_duplicate_bios().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index b8cdd8c..280c17a 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1195,12 +1195,6 @@ static void __map_bio(struct bio *clone)
        }
 }
 
-static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len)
-{
-       bio->bi_iter.bi_sector = sector;
-       bio->bi_iter.bi_size = to_bytes(len);
-}
-
 static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci,
                                struct dm_target *ti, unsigned num_bios,
                                unsigned *len)
@@ -1243,14 +1237,14 @@ static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti,
        case 1:
                clone = alloc_tio(ci, ti, 0, len, GFP_NOIO);
                if (len)
-                       bio_setup_sector(clone, ci->sector, *len);
+                       clone->bi_iter.bi_size = to_bytes(*len);
                __map_bio(clone);
                break;
        default:
                alloc_multiple_bios(&blist, ci, ti, num_bios, len);
                while ((clone = bio_list_pop(&blist))) {
                        if (len)
-                               bio_setup_sector(clone, ci->sector, *len);
+                               clone->bi_iter.bi_size = to_bytes(*len);
                        __map_bio(clone);
                }
                break;
@@ -1369,7 +1363,6 @@ static int __split_and_process_bio(struct clone_info *ci)
        len = min_t(sector_t, max_io_len(ti, ci->sector), ci->sector_count);
 
        clone = alloc_tio(ci, ti, 0, &len, GFP_NOIO);
-       bio_advance(clone, to_bytes(ci->sector - clone->bi_iter.bi_sector));
        clone->bi_iter.bi_size = to_bytes(len);
        if (bio_integrity(clone))
                bio_integrity_trim(clone);