md: add takeover support for raid4 -> raid5 conversion.

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

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 8a5e14e4a8519e7ab571cfd59a5163dae924bae7..95953273c4d9e0fc8b0e1eebc55f27775f080c31 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4967,6 +4967,11 @@ static void *raid5_takeover(mddev_t *mddev)
 
        if (mddev->level == 1)
                return raid5_takeover_raid1(mddev);
+       if (mddev->level == 4) {
+               mddev->new_layout = ALGORITHM_PARITY_N;
+               mddev->new_level = 5;
+               return setup_conf(mddev);
+       }
 
        return ERR_PTR(-EINVAL);
 }