ceph: allow renewal of auth credentials

Add infrastructure to allow the mon_client to periodically renew its auth
credentials.  Also add a messenger callback that will force such a renewal
if a peer rejects our authenticator.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 62d9ae4..770f7b5 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -123,9 +123,9 @@
 	struct super_block *sb;
 
 	unsigned long mount_state;
-	wait_queue_head_t mount_wq;
+	wait_queue_head_t auth_wq;
 
-	int mount_err;
+	int auth_err;
 
 	struct ceph_messenger *msgr;   /* messenger instance */
 	struct ceph_mon_client monc;