md: add a new api prepare_suspend() in md_personality

There are no functional changes, the new api will be used later to do
special handling for raid456 in md_suspend().

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230512015610.821290-5-yukuai1@huaweicloud.com

diff --git a/drivers/md/md.c b/drivers/md/md.c
index fb060e3..2f29d4e 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -448,6 +448,10 @@ void mddev_suspend(struct mddev *mddev)
        wake_up(&mddev->sb_wait);
        set_bit(MD_ALLOW_SB_UPDATE, &mddev->flags);
        percpu_ref_kill(&mddev->active_io);
+
+       if (mddev->pers->prepare_suspend)
+               mddev->pers->prepare_suspend(mddev);
+
        wait_event(mddev->sb_wait, percpu_ref_is_zero(&mddev->active_io));
        mddev->pers->quiesce(mddev, 1);
        clear_bit_unlock(MD_ALLOW_SB_UPDATE, &mddev->flags);

diff --git a/drivers/md/md.h b/drivers/md/md.h
index da173d6..1eec65c 100644 (file)
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -631,6 +631,7 @@ 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