+enum {
+ CLP_GANG_OKAY = 0,
+ CLP_GANG_RESCHED,
+ CLP_GANG_AGAIN,
+ CLP_GANG_ABORT
+};
+
+/* callback of cl_page_gang_lookup() */
+typedef int (*cl_page_gang_cb_t) (const struct lu_env *, struct cl_io *,
+ struct cl_page *, void *);
+int cl_page_gang_lookup (const struct lu_env *env,
+ struct cl_object *obj,
+ struct cl_io *io,
+ pgoff_t start, pgoff_t end,
+ cl_page_gang_cb_t cb, void *cbdata);
+struct cl_page *cl_page_lookup (struct cl_object_header *hdr,