diff --git a/include/linux/wait.h b/include/linux/wait.h index 1dee81c41ff..f0e1ca2118f 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -346,6 +346,75 @@ do { \ __ret; \ }) +/** + * wait_io_event_interruptible - sleep until an io condition gets true + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_INTERRUPTIBLE) until the + * @condition evaluates to true or a signal is received. + * The @condition is checked each time the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * The function will return -ERESTARTSYS if it was interrupted by a + * signal and 0 if @condition evaluated to true. + */ +#define wait_io_event_interruptible(wq, condition) \ +({ \ + int __ret = 0; \ + if (!(condition)) \ + __wait_io_event_interruptible(wq, condition, __ret); \ + __ret; \ +}) + +#define __wait_io_event_interruptible_timeout(wq, condition, ret) \ +do { \ + DEFINE_WAIT(__wait); \ + \ + for (;;) { \ + prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ + if (condition) \ + break; \ + if (!signal_pending(current)) { \ + ret = io_schedule_timeout(ret); \ + if (!ret) \ + break; \ + continue; \ + } \ + ret = -ERESTARTSYS; \ + break; \ + } \ + finish_wait(&wq, &__wait); \ +} while (0) + +/** + * wait_io_event_interruptible_timeout - sleep until an io condition gets true or a timeout elapses + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * @timeout: timeout, in jiffies + * + * The process is put to sleep (TASK_INTERRUPTIBLE) until the + * @condition evaluates to true or a signal is received. + * The @condition is checked each time the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it + * was interrupted by a signal, and the remaining jiffies otherwise + * if the condition evaluated to true before the timeout elapsed. + */ + +#define wait_io_event_interruptible_timeout(wq, condition, timeout) \ +({ \ + long __ret = timeout; \ + if (!(condition)) \ + __wait_io_event_interruptible_timeout(wq, condition, __ret); \ + __ret; \ +}) + #define __wait_event_interruptible_exclusive(wq, condition, ret) \ do { \ DEFINE_WAIT(__wait); \