6.8-stable review patch. If anyone has any objections, please let me know.
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From: Yu Kuai yukuai3@huawei.com
[ Upstream commit 5625ff8b72b0e5c13b0fc1fc1f198155af45f729 ]
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: Yu Kuai yukuai3@huawei.com Signed-off-by: Xiao Ni xni@redhat.com Acked-by: Mike Snitzer snitzer@kernel.org Signed-off-by: Song Liu song@kernel.org Link: https://lore.kernel.org/r/20240305072306.2562024-8-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/dm-raid.c | 18 ++++++++++++++++++ drivers/md/md.h | 1 + 2 files changed, 19 insertions(+)
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 8d38cdb221453..b8f5304ca00d1 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -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, diff --git a/drivers/md/md.h b/drivers/md/md.h index ea0fd76c17e75..24261f9b676d5 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -649,6 +649,7 @@ 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