Patch "md: export helpers to stop sync_thread" has been added to the 6.8-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    md: export helpers to stop sync_thread

to the 6.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     md-export-helpers-to-stop-sync_thread.patch
and it can be found in the queue-6.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit d2046064404bd93cc8575945ef6c7d533e7de998
Author: Yu Kuai <yukuai3@xxxxxxxxxx>
Date:   Tue Mar 5 15:22:59 2024 +0800

    md: export helpers to stop sync_thread
    
    [ Upstream commit 7a2347e284d7ec2f0759be4db60fa7ca937284fc ]
    
    Add new helpers:
    
      void md_idle_sync_thread(struct mddev *mddev);
      void md_frozen_sync_thread(struct mddev *mddev);
      void md_unfrozen_sync_thread(struct mddev *mddev);
    
    The helpers will be used in dm-raid in later patches to fix regressions
    and prevent calling md_reap_sync_thread() directly.
    
    Cc: stable@xxxxxxxxxxxxxxx # v6.7+
    Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
    Signed-off-by: Xiao Ni <xni@xxxxxxxxxx>
    Acked-by: Mike Snitzer <snitzer@xxxxxxxxxx>
    Signed-off-by: Song Liu <song@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20240305072306.2562024-3-yukuai1@xxxxxxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3d3a419190042..7255678608e7c 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4920,6 +4920,35 @@ static void stop_sync_thread(struct mddev *mddev, bool locked, bool check_seq)
 		mddev_lock_nointr(mddev);
 }
 
+void md_idle_sync_thread(struct mddev *mddev)
+{
+	lockdep_assert_held(&mddev->reconfig_mutex);
+
+	clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
+	stop_sync_thread(mddev, true, true);
+}
+EXPORT_SYMBOL_GPL(md_idle_sync_thread);
+
+void md_frozen_sync_thread(struct mddev *mddev)
+{
+	lockdep_assert_held(&mddev->reconfig_mutex);
+
+	set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
+	stop_sync_thread(mddev, true, false);
+}
+EXPORT_SYMBOL_GPL(md_frozen_sync_thread);
+
+void md_unfrozen_sync_thread(struct mddev *mddev)
+{
+	lockdep_assert_held(&mddev->reconfig_mutex);
+
+	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_action);
+}
+EXPORT_SYMBOL_GPL(md_unfrozen_sync_thread);
+
 static void idle_sync_thread(struct mddev *mddev)
 {
 	mutex_lock(&mddev->sync_mutex);
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 27d187ca6258a..0d06d640aa06d 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -782,6 +782,9 @@ extern void md_rdev_clear(struct md_rdev *rdev);
 extern void md_handle_request(struct mddev *mddev, struct bio *bio);
 extern int mddev_suspend(struct mddev *mddev, bool interruptible);
 extern void mddev_resume(struct mddev *mddev);
+extern void md_idle_sync_thread(struct mddev *mddev);
+extern void md_frozen_sync_thread(struct mddev *mddev);
+extern void md_unfrozen_sync_thread(struct mddev *mddev);
 
 extern void md_reload_sb(struct mddev *mddev, int raid_disk);
 extern void md_update_sb(struct mddev *mddev, int force);