libceph: fsmap.user subscription support

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
diff --git a/include/linux/ceph/mon_client.h b/include/linux/ceph/mon_client.h
index e2a92df..24d704d 100644
--- a/include/linux/ceph/mon_client.h
+++ b/include/linux/ceph/mon_client.h
@@ -95,7 +95,7 @@
 		struct ceph_mon_subscribe_item item;
 		bool want;
 		u32 have; /* epoch */
-	} subs[3];
+	} subs[4];
 	int fs_cluster_id; /* "mdsmap.<id>" sub */
 
 #ifdef CONFIG_DEBUG_FS
@@ -111,9 +111,10 @@
 extern void ceph_monc_stop(struct ceph_mon_client *monc);
 
 enum {
-	CEPH_SUB_MDSMAP = 0,
-	CEPH_SUB_MONMAP,
+	CEPH_SUB_MONMAP = 0,
 	CEPH_SUB_OSDMAP,
+	CEPH_SUB_FSMAP,
+	CEPH_SUB_MDSMAP,
 };
 
 extern const char *ceph_sub_str[];