From: Yu Kuai <yukuai3@huawei.com> mainline inclusion from mainline-v6.9-rc1 commit 5625ff8b72b0e5c13b0fc1fc1f198155af45f729 category: bugfix bugzilla: 190197 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- 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: Li Nan <linan122@huawei.com> --- drivers/md/md.h | 1 + drivers/md/dm-raid.c | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+) diff --git a/drivers/md/md.h b/drivers/md/md.h index 3012bbc09aaa..05b3286e5ae2 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -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 diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 0fa6d7b55030..4d89a4947217 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3795,6 +3795,23 @@ 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; @@ -4081,6 +4098,7 @@ 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, -- 2.39.2