ceph: Don't update i_max_size when handling non-auth cap

The cap from non-auth mds doesn't have a meaningful max_size value.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: NSage Weil <sage@inktank.com>

fs/ceph/caps.c

@@ -2390,7 +2390,7 @@ static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
 			    &atime);
 
 	/* max size increase? */
-	if (max_size != ci->i_max_size) {
+	if (ci->i_auth_cap == cap && max_size != ci->i_max_size) {
 		dout("max_size %lld -> %llu\n", ci->i_max_size, max_size);
 		ci->i_max_size = max_size;
 		if (max_size >= ci->i_wanted_max_size) {