md: factor out helper to start reshape from action_store()

There are no functional changes, just to make code cleaner and prepare
for following refactor.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-5-yukuai1@huaweicloud.com

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 4ce8d164cde97d101365fab2b58ae2c064f7040e..b34ae9fbd24671411fa7e3a562b77b32951724d8 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5071,6 +5071,45 @@ static void frozen_sync_thread(struct mddev *mddev)
        mutex_unlock(&mddev->sync_mutex);
 }
 
+static int mddev_start_reshape(struct mddev *mddev)
+{
+       int ret;
+
+       if (mddev->pers->start_reshape == NULL)
+               return -EINVAL;
+
+       ret = mddev_lock(mddev);
+       if (ret)
+               return ret;
+
+       if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
+               mddev_unlock(mddev);
+               return -EBUSY;
+       }
+
+       if (mddev->reshape_position == MaxSector ||
+           mddev->pers->check_reshape == NULL ||
+           mddev->pers->check_reshape(mddev)) {
+               clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
+               ret = mddev->pers->start_reshape(mddev);
+               if (ret) {
+                       mddev_unlock(mddev);
+                       return ret;
+               }
+       } else {
+               /*
+                * If reshape is still in progress, and md_check_recovery() can
+                * continue to reshape, don't restart reshape because data can
+                * be corrupted for raid456.
+                */
+               clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
+       }
+
+       mddev_unlock(mddev);
+       sysfs_notify_dirent_safe(mddev->sysfs_degraded);
+       return 0;
+}
+
 static ssize_t
 action_store(struct mddev *mddev, const char *page, size_t len)
 {
@@ -5090,32 +5129,10 @@ action_store(struct mddev *mddev, const char *page, size_t len)
                clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
                set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
        } else if (cmd_match(page, "reshape")) {
-               int err;
-               if (mddev->pers->start_reshape == NULL)
-                       return -EINVAL;
-               err = mddev_lock(mddev);
-               if (!err) {
-                       if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
-                               err =  -EBUSY;
-                       } else if (mddev->reshape_position == MaxSector ||
-                                  mddev->pers->check_reshape == NULL ||
-                                  mddev->pers->check_reshape(mddev)) {
-                               clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
-                               err = mddev->pers->start_reshape(mddev);
-                       } else {
-                               /*
-                                * If reshape is still in progress, and
-                                * md_check_recovery() can continue to reshape,
-                                * don't restart reshape because data can be
-                                * corrupted for raid456.
-                                */
-                               clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
-                       }
-                       mddev_unlock(mddev);
-               }
+               int err = mddev_start_reshape(mddev);
+
                if (err)
                        return err;
-               sysfs_notify_dirent_safe(mddev->sysfs_degraded);
        } else {
                if (cmd_match(page, "check"))
                        set_bit(MD_RECOVERY_CHECK, &mddev->recovery);