1 files changed, 37 insertions, 20 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index ca011d1d1de7..429e95e9a942 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2375,6 +2375,36 @@ repeat:
 }
 EXPORT_SYMBOL(md_update_sb);
 
+static int add_bound_rdev(struct md_rdev *rdev)
+{
+	struct mddev *mddev = rdev->mddev;
+	int err = 0;
+
+	if (!mddev->pers->hot_remove_disk) {
+		/* If there is hot_add_disk but no hot_remove_disk
+		 * then added disks for geometry changes,
+		 * and should be added immediately.
+		 */
+		super_types[mddev->major_version].
+			validate_super(mddev, rdev);
+		err = mddev->pers->hot_add_disk(mddev, rdev);
+		if (err) {
+			unbind_rdev_from_array(rdev);
+			export_rdev(rdev);
+			return err;
+		}
+	}
+	sysfs_notify_dirent_safe(rdev->sysfs_state);
+
+	set_bit(MD_CHANGE_DEVS, &mddev->flags);
+	if (mddev->degraded)
+		set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
+	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
+	md_new_event(mddev);
+	md_wakeup_thread(mddev->thread);
+	return 0;
+}
+
 /* words written to sysfs files may, or may not, be \n terminated.
  * We want to accept with case. For this we use cmd_match.
  */
@@ -2564,6 +2594,12 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
 			clear_bit(Replacement, &rdev->flags);
 			err = 0;
 		}
+	} else if (cmd_match(buf, "re-add")) {
+		if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1)) {
+			clear_bit(Faulty, &rdev->flags);
+			err = add_bound_rdev(rdev);
+		} else
+			err = -EBUSY;
 	}
 	if (!err)
 		sysfs_notify_dirent_safe(rdev->sysfs_state);
@@ -5875,29 +5911,10 @@ static int add_new_disk(struct mddev *mddev, mdu_disk_info_t *info)
 
 		rdev->raid_disk = -1;
 		err = bind_rdev_to_array(rdev, mddev);
-		if (!err && !mddev->pers->hot_remove_disk) {
-			/* If there is hot_add_disk but no hot_remove_disk
-			 * then added disks for geometry changes,
-			 * and should be added immediately.
-			 */
-			super_types[mddev->major_version].
-				validate_super(mddev, rdev);
-			err = mddev->pers->hot_add_disk(mddev, rdev);
-			if (err)
-				unbind_rdev_from_array(rdev);
-		}
 		if (err)
 			export_rdev(rdev);
 		else
-			sysfs_notify_dirent_safe(rdev->sysfs_state);
-
-		set_bit(MD_CHANGE_DEVS, &mddev->flags);
-		if (mddev->degraded)
-			set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
-		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
-		if (!err)
-			md_new_event(mddev);
-		md_wakeup_thread(mddev->thread);
+			err = add_bound_rdev(rdev);
 		if (mddev_is_clustered(mddev) &&
 				(info->state & (1 << MD_DISK_CLUSTER_ADD)))
 			md_cluster_ops->add_new_disk_finish(mddev);