[PATCH v3 09/12] dm-raid: add a new helper prepare_suspend() in md_personality

From: Yu Kuai
Date: Sat Jan 27 2024 - 02:55:27 EST


From: Yu Kuai <yukuai3@xxxxxxxxxx>

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

Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/md/dm-raid.c | 10 +++++++---
drivers/md/md.h | 1 +
2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index f1637cf88559..ede2e4574ee5 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3806,10 +3806,14 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
static void raid_presuspend(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
+ struct mddev *mddev = &rs->md;

- mddev_lock_nointr(&rs->md);
- md_frozen_sync_thread(&rs->md);
- mddev_unlock(&rs->md);
+ mddev_lock_nointr(mddev);
+ md_frozen_sync_thread(mddev);
+ mddev_unlock(mddev);
+
+ if (mddev->pers && mddev->pers->prepare_suspend)
+ mddev->pers->prepare_suspend(mddev);
}

static void raid_presuspend_undo(struct dm_target *ti)
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 437ab70ce79b..29b476ff3b9f 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -617,6 +617,7 @@ 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
--
2.39.2