imsm: add --update=uuid support

When disks have conflicting container memberships (same container ids
but incompatible member arrays) --update=uuid can be used to move
offenders to a new container id by changing 'orig_family_num'.

Note that this only supports random updates of the uuid as the actual
uuid is synthesized.  We also need to communicate the new
'orig_family_num' value to all disks involved in the update.  A new
field 'update_private' is added to struct mdinfo to allow this
information to be transmitted.

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

1 files changed, 5 insertions, 0 deletions

diff --git a/mdadm.h b/mdadm.h
index 91ba624..04b87b8 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -153,6 +153,11 @@ struct mdinfo {
 	int			cache_size; /* size of raid456 stripe cache*/
 	int			mismatch_cnt;
 	char			text_version[50];
+	void 			*update_private; /* for passing metadata-format
+						  * specific update data
+						  * between successive calls to
+						  * update_super()
+						  */
 
 	int container_member; /* for assembling external-metatdata arrays
 			       * This is to be used internally by metadata