+ } else if (rdev->mddev->pers) {
+ mdk_rdev_t *rdev2;
+ struct list_head *tmp;
+ /* Activating a spare .. or possibly reactivating
+ * if we every get bitmaps working here.
+ */
+
+ if (rdev->raid_disk != -1)
+ return -EBUSY;
+
+ if (rdev->mddev->pers->hot_add_disk == NULL)
+ return -EINVAL;
+
+ rdev_for_each(rdev2, tmp, rdev->mddev)
+ if (rdev2->raid_disk == slot)
+ return -EEXIST;
+
+ rdev->raid_disk = slot;
+ if (test_bit(In_sync, &rdev->flags))
+ rdev->saved_raid_disk = slot;
+ else
+ rdev->saved_raid_disk = -1;
+ err = rdev->mddev->pers->
+ hot_add_disk(rdev->mddev, rdev);
+ if (err != 1) {
+ rdev->raid_disk = -1;
+ if (err == 0)
+ return -EEXIST;
+ return err;
+ }
+ sprintf(nm, "rd%d", rdev->raid_disk);
+ if (sysfs_create_link(&rdev->mddev->kobj, &rdev->kobj, nm))
+ printk(KERN_WARNING
+ "md: cannot register "
+ "%s for %s\n",
+ nm, mdname(rdev->mddev));
+
+ /* don't wakeup anyone, leave that to userspace. */