md/raid0: convert raid0_handle_discard() to use bio_submit_split_bioset()

Unify bio split code, and prepare to fix ordering of split IO

Noted commit 319ff40a5427 ("md/raid0: Fix performance regression for large
sequential writes") already fix ordering of split IO by remapping bio to
underlying disks before resubmitting it, with the respect
md_submit_bio() already split it by sectors, and raid0_make_request()
will split at most once for unaligned IO. This is a bit hacky and we'll
convert this to solution in general later.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index 1ba7d0c090f7efbdebc744138066763fa8e50e1e..ca08ec2e1f2742c3b8260d7d2100b401ce16a4db 100644 (file)
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -463,23 +463,16 @@ static void raid0_handle_discard(struct mddev *mddev, struct bio *bio)
        zone = find_zone(conf, &start);
 
        if (bio_end_sector(bio) > zone->zone_end) {
-               struct bio *split = bio_split(bio,
-                       zone->zone_end - bio->bi_iter.bi_sector, GFP_NOIO,
-                       &mddev->bio_set);
-
-               if (IS_ERR(split)) {
-                       bio->bi_status = errno_to_blk_status(PTR_ERR(split));
-                       bio_endio(bio);
+               bio = bio_submit_split_bioset(bio,
+                               zone->zone_end - bio->bi_iter.bi_sector,
+                               &mddev->bio_set);
+               if (!bio)
                        return;
-               }
 
-               bio_chain(split, bio);
-               trace_block_split(split, bio->bi_iter.bi_sector);
-               submit_bio_noacct(bio);
-               bio = split;
                end = zone->zone_end;
-       } else
+       } else {
                end = bio_end_sector(bio);
+       }
 
        orig_end = end;
        if (zone != conf->strip_zone)