Commit a1d9b4fd authored by John Garry's avatar John Garry Committed by Jens Axboe
Browse files

md/raid10: 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/20241118105018.1870052-6-john.g.garry@oracle.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent f2a38abf

drivers/md/raid10.c

+18 −2
Original line number Diff line number Diff line
@@ -1255,6 +1255,7 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio, 
	const enum req_op op = bio_op(bio);

	const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC;

	const blk_opf_t do_fua = bio->bi_opf & REQ_FUA;

	const blk_opf_t do_atomic = bio->bi_opf & REQ_ATOMIC;

	unsigned long flags;

	struct r10conf *conf = mddev->private;

	struct md_rdev *rdev;
@@ -1273,7 +1274,7 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio, 
	mbio->bi_iter.bi_sector	= (r10_bio->devs[n_copy].addr +

				   choose_data_offset(r10_bio, rdev));

	mbio->bi_end_io	= raid10_end_write_request;

	mbio->bi_opf = op | do_sync | do_fua;

	mbio->bi_opf = op | do_sync | do_fua | do_atomic;

	if (!replacement && test_bit(FailFast,

				     &conf->mirrors[devnum].rdev->flags)

			 && enough(conf, devnum))
@@ -1468,7 +1469,21 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, 
				continue;

			}

			if (is_bad) {

				int good_sectors = first_bad - dev_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 - dev_sector;

				if (good_sectors < max_sectors)

					max_sectors = good_sectors;

			}
@@ -4025,6 +4040,7 @@ static int raid10_set_queue_limits(struct mddev *mddev) 
	lim.max_write_zeroes_sectors = 0;

	lim.io_min = mddev->chunk_sectors << 9;

	lim.io_opt = lim.io_min * raid10_nr_stripes(conf);

	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);