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);