Commit 5625ff8b authored by Yu Kuai's avatar Yu Kuai Committed by Song Liu
Browse files

dm-raid: add a new helper prepare_suspend() in md_personality 



There are no functional changes for now, prepare to fix a deadlock for
dm-raid456.

Cc: stable@vger.kernel.org # v6.7+
Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Signed-off-by: default avatarXiao Ni <xni@redhat.com>
Acked-by: default avatarMike Snitzer <snitzer@kernel.org>
Signed-off-by: default avatarSong Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240305072306.2562024-8-yukuai1@huaweicloud.com
parent cd32b27a

drivers/md/dm-raid.c

+18 −0
Original line number Diff line number Diff line
@@ -3803,6 +3803,23 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 
	blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));

}



static void raid_presuspend(struct dm_target *ti)

{

	struct raid_set *rs = ti->private;

	struct mddev *mddev = &rs->md;



	if (!reshape_interrupted(mddev))

		return;



	/*

	 * For raid456, if reshape is interrupted, IO across reshape position

	 * will never make progress, while caller will wait for IO to be done.

	 * Inform raid456 to handle those IO to prevent deadlock.

	 */

	if (mddev->pers && mddev->pers->prepare_suspend)

		mddev->pers->prepare_suspend(mddev);

}



static void raid_postsuspend(struct dm_target *ti)

{

	struct raid_set *rs = ti->private;
@@ -4087,6 +4104,7 @@ static struct target_type raid_target = { 
	.message = raid_message,

	.iterate_devices = raid_iterate_devices,

	.io_hints = raid_io_hints,

	.presuspend = raid_presuspend,

	.postsuspend = raid_postsuspend,

	.preresume = raid_preresume,

	.resume = raid_resume,

drivers/md/md.h

+1 −0
Original line number Diff line number Diff line
@@ -659,6 +659,7 @@ struct md_personality 
	int (*start_reshape) (struct mddev *mddev);

	void (*finish_reshape) (struct mddev *mddev);

	void (*update_reshape_pos) (struct mddev *mddev);

	void (*prepare_suspend) (struct mddev *mddev);

	/* quiesce suspends or resumes internal processing.

	 * 1 - stop new actions and wait for action io to complete

	 * 0 - return to normal behaviour