linux-master/kernel/reboot.c

166  *	@nb: Info about handler function to be called
169  *			0:	Restart handler of last resort,
171  *			128:	Default restart handler; use if no other
172  *				restart handler is expected to be available,
175  *			255:	Highest priority restart handler, will
186  *	If more than one function is registered, the restart handler priority
192  *	restart handlers may exist; for example, one restart handler might
194  *	In such cases, the restart handler which only restarts part of the
209  *				     restart handler
212  *	Unregisters a previously registered restart handler function.
223  *	do_kernel_restart - Execute kernel restart handler call chain
230  *	Restarts the system immediately if a restart handler function has been
332 	struct sys_off_handler *handler;
335 	handler = container_of(nb, struct sys_off_handler, nb);
336 	data.cb_data = handler->cb_data;
339 	data.dev = handler->dev;
341 	return handler->sys_off_cb(&data);
348 	struct sys_off_handler *handler;
352 	 * Platforms like m68k can't allocate sys_off handler dynamically
356 		handler = &platform_sys_off_handler;
357 		if (handler->cb_data)
365 		handler = kzalloc(sizeof(*handler), flags);
366 		if (!handler)
370 	return handler;
373 static void free_sys_off_handler(struct sys_off_handler *handler)
375 	if (handler == &platform_sys_off_handler)
376 		memset(handler, 0, sizeof(*handler));
378 		kfree(handler);
382  *	register_sys_off_handler - Register sys-off handler
388  *	Registers system power-off or restart handler that will be invoked
390  *	should return NOTIFY_DONE to permit execution of the next handler in
396  *	Only one handler can be registered at the non-default priority level,
408 	struct sys_off_handler *handler;
411 	handler = alloc_sys_off_handler(priority);
412 	if (IS_ERR(handler))
413 		return handler;
417 		handler->list = &power_off_prep_handler_list;
418 		handler->blocking = true;
422 		handler->list = &power_off_handler_list;
426 		handler->list = &restart_prep_handler_list;
427 		handler->blocking = true;
431 		handler->list = &restart_handler_list;
435 		free_sys_off_handler(handler);
439 	handler->nb.notifier_call = sys_off_notify;
440 	handler->nb.priority = priority;
441 	handler->sys_off_cb = callback;
442 	handler->cb_data = cb_data;
443 	handler->mode = mode;
445 	if (handler->blocking) {
447 			err = blocking_notifier_chain_register(handler->list,
448 							       &handler->nb);
450 			err = blocking_notifier_chain_register_unique_prio(handler->list,
451 									   &handler->nb);
454 			err = atomic_notifier_chain_register(handler->list,
455 							     &handler->nb);
457 			err = atomic_notifier_chain_register_unique_prio(handler->list,
458 									 &handler->nb);
462 		free_sys_off_handler(handler);
466 	return handler;
471  *	unregister_sys_off_handler - Unregister sys-off handler
472  *	@handler: Sys-off handler
474  *	Unregisters given sys-off handler.
476 void unregister_sys_off_handler(struct sys_off_handler *handler)
480 	if (IS_ERR_OR_NULL(handler))
483 	if (handler->blocking)
484 		err = blocking_notifier_chain_unregister(handler->list,
485 							 &handler->nb);
487 		err = atomic_notifier_chain_unregister(handler->list,
488 						       &handler->nb);
493 	free_sys_off_handler(handler);
499 	struct sys_off_handler *handler = data;
501 	unregister_sys_off_handler(handler);
505  *	devm_register_sys_off_handler - Register sys-off handler
506  *	@dev: Device that registers handler
512  *	Registers resource-managed sys-off handler.
522 	struct sys_off_handler *handler;
524 	handler = register_sys_off_handler(mode, priority, callback, cb_data);
525 	if (IS_ERR(handler))
526 		return PTR_ERR(handler);
527 	handler->dev = dev;
530 					handler);
535  *	devm_register_power_off_handler - Register power-off handler
540  *	Registers resource-managed sys-off handler with a default priority
557  *	devm_register_restart_handler - Register restart handler
562  *	Registers resource-managed sys-off handler with a default priority
602 	struct sys_off_handler *handler;
604 	handler = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,
608 	if (IS_ERR(handler))
609 		return PTR_ERR(handler);
611 	platform_power_off_handler = handler;
647  *	do_kernel_power_off - Execute kernel power-off handler call chain
651  *	Powers off the system immediately if a power-off handler function has
678  *	Returns true if power-off handler is registered and system can be