[PATCH v4 3/5] md/raid0: Atomic write support

[John Garry]

Set BLK_FEAT_ATOMIC_WRITES_STACKED to enable atomic writes. All other
stacked device request queue limits should automatically be set properly.
With regards to atomic write max bytes limit, this will be set at
hw_max_sectors and this is limited by the stripe width, which we want.

Reviewed-by: Yu Kuai <yukuai3@xxxxxxxxxx>
Signed-off-by: John Garry <john.g.garry@xxxxxxxxxx>
---
 drivers/md/raid0.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index baaf5f8b80ae..7049ec7fb8eb 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -384,6 +384,7 @@ static int raid0_set_limits(struct mddev *mddev)
 	lim.max_write_zeroes_sectors = mddev->chunk_sectors;
 	lim.io_min = mddev->chunk_sectors << 9;
 	lim.io_opt = lim.io_min * mddev->raid_disks;
+	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);
-- 
2.31.1