md: remove test for duplicate device when setting slot number.

When setting the slot number on a device in an active array we
currently check that the number is not already in use.
We then call into the personality's hot_add_disk function
which performs the same test and returns the same error.

Thus the common test is not needed.

As we will shortly be changing some personalities to allow duplicates
in some cases (to support hot-replace), the common test will become
inconvenient.

So remove the common test.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index f97c3b2f2f89e6785892ef8fc563ddab946be13d..b4ab31f02d23ef7ffb43445593a45b9b8c733c32 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2696,7 +2696,6 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
                md_wakeup_thread(rdev->mddev->thread);
        } else if (rdev->mddev->pers) {
-               struct md_rdev *rdev2;
                /* Activating a spare .. or possibly reactivating
                 * if we ever get bitmaps working here.
                 */
@@ -2710,10 +2709,6 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
                if (rdev->mddev->pers->hot_add_disk == NULL)
                        return -EINVAL;
 
-               list_for_each_entry(rdev2, &rdev->mddev->disks, same_set)
-                       if (rdev2->raid_disk == slot)
-                               return -EEXIST;
-
                if (slot >= rdev->mddev->raid_disks &&
                    slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
                        return -ENOSPC;