Fix remove_and_add_spares removes drive added as spare in slot_store

Commit 2910ff17d154baa5eb50e362a91104e831eb2bb6
introduced a regression which would remove a recently added spare via
slot_store. Revert part of the patch which touches slot_store() and add
the disk directly using pers->hot_add_disk()

Fixes: 2910ff17d154 ("md: remove_and_add_spares() to activate specific
rdev")
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Signed-off-by: NeilBrown <neilb@suse.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index b79b95784e46..dbedc58d8c00 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2774,6 +2774,7 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
                 /* Activating a spare .. or possibly reactivating
                  * if we ever get bitmaps working here.
                  */
+                int err;
 
                 if (rdev->raid_disk != -1)
                         return -EBUSY;
@@ -2795,9 +2796,15 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
                         rdev->saved_raid_disk = -1;
                 clear_bit(In_sync, &rdev->flags);
                 clear_bit(Bitmap_sync, &rdev->flags);
-                remove_and_add_spares(rdev->mddev, rdev);
-                if (rdev->raid_disk == -1)
-                        return -EBUSY;
+                err = rdev->mddev->pers->
+                        hot_add_disk(rdev->mddev, rdev);
+                if (err) {
+                        rdev->raid_disk = -1;
+                        return err;
+                } else
+                        sysfs_notify_dirent_safe(rdev->sysfs_state);
+                if (sysfs_link_rdev(rdev->mddev, rdev))
+                        /* failure here is OK */;
                 /* don't wakeup anyone, leave that to userspace. */
         } else {
                 if (slot >= rdev->mddev->raid_disks &&