NFS: define a function to update nfsi->cache_change_attribute

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index cc3a09d..5747d49 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1029,7 +1029,8 @@
 			dprintk("NFS: mtime change on server for file %s/%ld\n",
 					inode->i_sb->s_id, inode->i_ino);
 			invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
-			nfsi->cache_change_attribute = now;
+			if (S_ISDIR(inode->i_mode))
+				nfs_force_lookup_revalidate(inode);
 		}
 		/* If ctime has changed we should definitely clear access+acl caches */
 		if (!timespec_equal(&inode->i_ctime, &fattr->ctime))
@@ -1038,7 +1039,8 @@
 		dprintk("NFS: change_attr change on server for file %s/%ld\n",
 				inode->i_sb->s_id, inode->i_ino);
 		invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
-		nfsi->cache_change_attribute = now;
+		if (S_ISDIR(inode->i_mode))
+			nfs_force_lookup_revalidate(inode);
 	}
 
 	/* Check if our cached file size is stale */