Commit 7d2affce authored by Jens Axboe's avatar Jens Axboe
Browse files

Merge tag 'md-fixes-20231206' of... 

Merge tag 'md-fixes-20231206' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md into block-6.7

Pull MD fixes from Song:

"This set from Yu Kuai fixes issues around sync_work, which was introduced
 in 6.7 kernels."

* tag 'md-fixes-20231206' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md:
  md: fix stopping sync thread
  md: don't leave 'MD_RECOVERY_FROZEN' in error path of md_set_readonly()
  md: fix missing flush of sync_work
parents a134cd8d f52f5c71

drivers/md/md.c

+50 −64
Original line number Diff line number Diff line
@@ -4840,25 +4840,29 @@ action_show(struct mddev *mddev, char *page) 
	return sprintf(page, "%s\n", type);

}



static void stop_sync_thread(struct mddev *mddev)

/**

 * stop_sync_thread() - wait for sync_thread to stop if it's running.

 * @mddev:	the array.

 * @locked:	if set, reconfig_mutex will still be held after this function

 *		return; if not set, reconfig_mutex will be released after this

 *		function return.

 * @check_seq:	if set, only wait for curent running sync_thread to stop, noted

 *		that new sync_thread can still start.

 */

static void stop_sync_thread(struct mddev *mddev, bool locked, bool check_seq)

{

	if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))

		return;

	int sync_seq;



	if (mddev_lock(mddev))

		return;

	if (check_seq)

		sync_seq = atomic_read(&mddev->sync_seq);



	/*

	 * Check again in case MD_RECOVERY_RUNNING is cleared before lock is

	 * held.

	 */

	if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {

		if (!locked)

			mddev_unlock(mddev);

		return;

	}



	if (work_pending(&mddev->del_work))

		flush_workqueue(md_misc_wq);

	mddev_unlock(mddev);



	set_bit(MD_RECOVERY_INTR, &mddev->recovery);

	/*
@@ -4866,21 +4870,28 @@ static void stop_sync_thread(struct mddev *mddev) 
	 * never happen

	 */

	md_wakeup_thread_directly(mddev->sync_thread);

	if (work_pending(&mddev->sync_work))

		flush_work(&mddev->sync_work);



	mddev_unlock(mddev);

	wait_event(resync_wait,

		   !test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||

		   (check_seq && sync_seq != atomic_read(&mddev->sync_seq)));



	if (locked)

		mddev_lock_nointr(mddev);

}



static void idle_sync_thread(struct mddev *mddev)

{

	int sync_seq = atomic_read(&mddev->sync_seq);



	mutex_lock(&mddev->sync_mutex);

	clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

	stop_sync_thread(mddev);



	wait_event(resync_wait, sync_seq != atomic_read(&mddev->sync_seq) ||

			!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery));

	if (mddev_lock(mddev)) {

		mutex_unlock(&mddev->sync_mutex);

		return;

	}



	stop_sync_thread(mddev, false, true);

	mutex_unlock(&mddev->sync_mutex);

}
@@ -4888,11 +4899,13 @@ static void frozen_sync_thread(struct mddev *mddev) 
{

	mutex_lock(&mddev->sync_mutex);

	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

	stop_sync_thread(mddev);



	wait_event(resync_wait, mddev->sync_thread == NULL &&

			!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery));

	if (mddev_lock(mddev)) {

		mutex_unlock(&mddev->sync_mutex);

		return;

	}



	stop_sync_thread(mddev, false, false);

	mutex_unlock(&mddev->sync_mutex);

}
@@ -6264,14 +6277,7 @@ static void md_clean(struct mddev *mddev) 


static void __md_stop_writes(struct mddev *mddev)

{

	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

	if (work_pending(&mddev->del_work))

		flush_workqueue(md_misc_wq);

	if (mddev->sync_thread) {

		set_bit(MD_RECOVERY_INTR, &mddev->recovery);

		md_reap_sync_thread(mddev);

	}



	stop_sync_thread(mddev, true, false);

	del_timer_sync(&mddev->safemode_timer);



	if (mddev->pers && mddev->pers->quiesce) {
@@ -6355,25 +6361,16 @@ static int md_set_readonly(struct mddev *mddev, struct block_device *bdev) 
	int err = 0;

	int did_freeze = 0;



	if (mddev->external && test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))

		return -EBUSY;



	if (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {

		did_freeze = 1;

		set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

		md_wakeup_thread(mddev->thread);

	}

	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))

		set_bit(MD_RECOVERY_INTR, &mddev->recovery);



	/*

	 * Thread might be blocked waiting for metadata update which will now

	 * never happen

	 */

	md_wakeup_thread_directly(mddev->sync_thread);



	if (mddev->external && test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))

		return -EBUSY;

	mddev_unlock(mddev);

	wait_event(resync_wait, !test_bit(MD_RECOVERY_RUNNING,

					  &mddev->recovery));

	stop_sync_thread(mddev, false, false);

	wait_event(mddev->sb_wait,

		   !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));

	mddev_lock_nointr(mddev);
@@ -6383,29 +6380,30 @@ static int md_set_readonly(struct mddev *mddev, struct block_device *bdev) 
	    mddev->sync_thread ||

	    test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {

		pr_warn("md: %s still in use.\n",mdname(mddev));

		if (did_freeze) {

			clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

			set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

			md_wakeup_thread(mddev->thread);

		}

		err = -EBUSY;

		goto out;

	}



	if (mddev->pers) {

		__md_stop_writes(mddev);



		if (mddev->ro == MD_RDONLY) {

			err  = -ENXIO;

		if (mddev->ro == MD_RDONLY)

			goto out;

		}



		mddev->ro = MD_RDONLY;

		set_disk_ro(mddev->gendisk, 1);

	}



out:

	if ((mddev->pers && !err) || did_freeze) {

		clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

		md_wakeup_thread(mddev->thread);

		sysfs_notify_dirent_safe(mddev->sysfs_state);

		err = 0;

	}

out:



	mutex_unlock(&mddev->open_mutex);

	return err;

}
@@ -6426,20 +6424,8 @@ static int do_md_stop(struct mddev *mddev, int mode, 
		set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);

		md_wakeup_thread(mddev->thread);

	}

	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))

		set_bit(MD_RECOVERY_INTR, &mddev->recovery);



	/*

	 * Thread might be blocked waiting for metadata update which will now

	 * never happen

	 */

	md_wakeup_thread_directly(mddev->sync_thread);



	mddev_unlock(mddev);

	wait_event(resync_wait, (mddev->sync_thread == NULL &&

				 !test_bit(MD_RECOVERY_RUNNING,

					   &mddev->recovery)));

	mddev_lock_nointr(mddev);

	stop_sync_thread(mddev, true, false);



	mutex_lock(&mddev->open_mutex);

	if ((mddev->pers && atomic_read(&mddev->openers) > !!bdev) ||