Support adding a spare to a live md array with external metadata.

[linux-2.6-omap-h63xx.git] / drivers / md / md.c

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3b5cd4ef54f1159b0b2b9434d1704ed75ec55b8d..5d6fac1fd39ebbaa05c522d78bcd997d08758018 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1932,7 +1932,7 @@ slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
                slot = -1;
        else if (e==buf || (*e && *e!= '\n'))
                return -EINVAL;
-       if (rdev->mddev->pers) {
+       if (rdev->mddev->pers && slot == -1) {
                /* Setting 'slot' on an active array requires also
                 * updating the 'rd%d' link, and communicating
                 * with the personality with ->hot_*_disk.
@@ -1940,8 +1940,6 @@ slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
                 * failed/spare devices.  This normally happens automatically,
                 * but not when the metadata is externally managed.
                 */
-               if (slot != -1)
-                       return -EBUSY;
                if (rdev->raid_disk == -1)
                        return -EEXIST;
                /* personality does all needed checks */
@@ -1955,6 +1953,44 @@ slot_store(mdk_rdev_t *rdev, const char *buf, size_t len)
                sysfs_remove_link(&rdev->mddev->kobj, nm);
                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
                md_wakeup_thread(rdev->mddev->thread);
+       } 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. */
        } else {
                if (slot >= rdev->mddev->raid_disks)
                        return -ENOSPC;