+void interface_set_available(struct interface *iface, bool new_state);
+int interface_set_up(struct interface *iface);
+int interface_set_down(struct interface *iface);
+void __interface_set_down(struct interface *iface, bool force);
+
+void interface_set_main_dev(struct interface *iface, struct device *dev);
+void interface_set_l3_dev(struct interface *iface, struct device *dev);
+
+void interface_add_user(struct interface_user *dep, struct interface *iface);
+void interface_remove_user(struct interface_user *dep);