[PATCH] md: ignore auto-readonly flag for arrays where it isn't meaningful

The 'auto-readonly' flag (which suppresses resync and superblock updates until
the first write) is not meaningful for personalities that don't support resync
or superblock writes (raid0, linear, etc).

So clear the setting early to avoid it confusing anything - e.g.  appearing in
/proc/mdstat
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/md/md.c

@@ -2058,6 +2058,9 @@ static int do_md_run(mddev_t * mddev)
 	}
 	if (mddev->pers->sync_request)
 		sysfs_create_group(&mddev->kobj, &md_redundancy_group);
+	else if (mddev->ro == 2) /* auto-readonly not meaningful */
+		mddev->ro = 0;
+
  	atomic_set(&mddev->writes_pending,0);
 	mddev->safemode = 0;
 	mddev->safemode_timer.function = md_safemode_timeout;