Commit f2a38abf authored by John Garry's avatar John Garry Committed by Jens Axboe
Browse files

md/raid1: Atomic write support 



Set BLK_FEAT_ATOMIC_WRITES_STACKED to enable atomic writes.

For an attempt to atomic write to a region which has bad blocks, error
the write as we just cannot do this. It is unlikely to find devices which
support atomic writes and bad blocks.

Reviewed-by: default avatarYu Kuai <yukuai3@huawei.com>
Signed-off-by: default avatarJohn Garry <john.g.garry@oracle.com>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20241118105018.1870052-5-john.g.garry@oracle.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent fa6fec82

drivers/md/raid1.c

+18 −2
Original line number Diff line number Diff line
@@ -1571,7 +1571,21 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, 
				continue;

			}

			if (is_bad) {

				int good_sectors = first_bad - r1_bio->sector;

				int good_sectors;



				/*

				 * We cannot atomically write this, so just

				 * error in that case. It could be possible to

				 * atomically write other mirrors, but the

				 * complexity of supporting that is not worth

				 * the benefit.

				 */

				if (bio->bi_opf & REQ_ATOMIC) {

					error = -EIO;

					goto err_handle;

				}



				good_sectors = first_bad - r1_bio->sector;

				if (good_sectors < max_sectors)

					max_sectors = good_sectors;

			}
@@ -1657,7 +1671,8 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, 


		mbio->bi_iter.bi_sector	= (r1_bio->sector + rdev->data_offset);

		mbio->bi_end_io	= raid1_end_write_request;

		mbio->bi_opf = bio_op(bio) | (bio->bi_opf & (REQ_SYNC | REQ_FUA));

		mbio->bi_opf = bio_op(bio) |

			(bio->bi_opf & (REQ_SYNC | REQ_FUA | REQ_ATOMIC));

		if (test_bit(FailFast, &rdev->flags) &&

		    !test_bit(WriteMostly, &rdev->flags) &&

		    conf->raid_disks - mddev->degraded > 1)
@@ -3224,6 +3239,7 @@ static int raid1_set_limits(struct mddev *mddev) 


	md_init_stacking_limits(&lim);

	lim.max_write_zeroes_sectors = 0;

	lim.features |= BLK_FEAT_ATOMIC_WRITES_STACKED;

	err = mddev_stack_rdev_limits(mddev, &lim, MDDEV_STACK_INTEGRITY);

	if (err) {

		queue_limits_cancel_update(mddev->gendisk->queue);