Create: allow per-metadata default layouts

Let handlers specifiy their own defaults, specifically needed for the
imsm-raid5 case where mdadm defaults to 'ls' and imsm to 'la'.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/mdadm.h b/mdadm.h
index 8220535..3ee2790 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -545,6 +545,8 @@ extern struct superswitch {
 				 int verbose);
 
 	struct mdinfo *(*container_content)(struct supertype *st);
+	/* Allow a metadata handler to override mdadm's default layouts */
+	int (*default_layout)(int level); /* optional */
 
 /* for mdmon */
 	int (*open_new)(struct supertype *c, struct active_array *a,