include/linux: Remove all users of FASTCALL() macro
[linux-2.6.git] / include / linux / wait.h
1 #ifndef _LINUX_WAIT_H
2 #define _LINUX_WAIT_H
3
4 #define WNOHANG         0x00000001
5 #define WUNTRACED       0x00000002
6 #define WSTOPPED        WUNTRACED
7 #define WEXITED         0x00000004
8 #define WCONTINUED      0x00000008
9 #define WNOWAIT         0x01000000      /* Don't reap, just poll status.  */
10
11 #define __WNOTHREAD     0x20000000      /* Don't wait on children of other threads in this group */
12 #define __WALL          0x40000000      /* Wait on all children, regardless of type */
13 #define __WCLONE        0x80000000      /* Wait only on non-SIGCHLD children */
14
15 /* First argument to waitid: */
16 #define P_ALL           0
17 #define P_PID           1
18 #define P_PGID          2
19
20 #ifdef __KERNEL__
21
22 #include <linux/list.h>
23 #include <linux/stddef.h>
24 #include <linux/spinlock.h>
25 #include <asm/system.h>
26 #include <asm/current.h>
27
28 typedef struct __wait_queue wait_queue_t;
29 typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int sync, void *key);
30 int default_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
31
32 struct __wait_queue {
33         unsigned int flags;
34 #define WQ_FLAG_EXCLUSIVE       0x01
35         void *private;
36         wait_queue_func_t func;
37         struct list_head task_list;
38 };
39
40 struct wait_bit_key {
41         void *flags;
42         int bit_nr;
43 };
44
45 struct wait_bit_queue {
46         struct wait_bit_key key;
47         wait_queue_t wait;
48 };
49
50 struct __wait_queue_head {
51         spinlock_t lock;
52         struct list_head task_list;
53 };
54 typedef struct __wait_queue_head wait_queue_head_t;
55
56 struct task_struct;
57
58 /*
59  * Macros for declaration and initialisaton of the datatypes
60  */
61
62 #define __WAITQUEUE_INITIALIZER(name, tsk) {                            \
63         .private        = tsk,                                          \
64         .func           = default_wake_function,                        \
65         .task_list      = { NULL, NULL } }
66
67 #define DECLARE_WAITQUEUE(name, tsk)                                    \
68         wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)
69
70 #define __WAIT_QUEUE_HEAD_INITIALIZER(name) {                           \
71         .lock           = __SPIN_LOCK_UNLOCKED(name.lock),              \
72         .task_list      = { &(name).task_list, &(name).task_list } }
73
74 #define DECLARE_WAIT_QUEUE_HEAD(name) \
75         wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
76
77 #define __WAIT_BIT_KEY_INITIALIZER(word, bit)                           \
78         { .flags = word, .bit_nr = bit, }
79
80 extern void init_waitqueue_head(wait_queue_head_t *q);
81
82 #ifdef CONFIG_LOCKDEP
83 # define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
84         ({ init_waitqueue_head(&name); name; })
85 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
86         wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
87 #else
88 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
89 #endif
90
91 static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p)
92 {
93         q->flags = 0;
94         q->private = p;
95         q->func = default_wake_function;
96 }
97
98 static inline void init_waitqueue_func_entry(wait_queue_t *q,
99                                         wait_queue_func_t func)
100 {
101         q->flags = 0;
102         q->private = NULL;
103         q->func = func;
104 }
105
106 static inline int waitqueue_active(wait_queue_head_t *q)
107 {
108         return !list_empty(&q->task_list);
109 }
110
111 /*
112  * Used to distinguish between sync and async io wait context:
113  * sync i/o typically specifies a NULL wait queue entry or a wait
114  * queue entry bound to a task (current task) to wake up.
115  * aio specifies a wait queue entry with an async notification
116  * callback routine, not associated with any task.
117  */
118 #define is_sync_wait(wait)      (!(wait) || ((wait)->private))
119
120 extern void add_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);
121 extern void add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait);
122 extern void remove_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);
123
124 static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new)
125 {
126         list_add(&new->task_list, &head->task_list);
127 }
128
129 /*
130  * Used for wake-one threads:
131  */
132 static inline void __add_wait_queue_tail(wait_queue_head_t *head,
133                                                 wait_queue_t *new)
134 {
135         list_add_tail(&new->task_list, &head->task_list);
136 }
137
138 static inline void __remove_wait_queue(wait_queue_head_t *head,
139                                                         wait_queue_t *old)
140 {
141         list_del(&old->task_list);
142 }
143
144 void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key);
145 extern void __wake_up_locked(wait_queue_head_t *q, unsigned int mode);
146 extern void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr);
147 void __wake_up_bit(wait_queue_head_t *, void *, int);
148 int __wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
149 int __wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
150 void wake_up_bit(void *, int);
151 int out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned);
152 int out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned);
153 wait_queue_head_t *bit_waitqueue(void *, int);
154
155 #define wake_up(x)                      __wake_up(x, TASK_NORMAL, 1, NULL)
156 #define wake_up_nr(x, nr)               __wake_up(x, TASK_NORMAL, nr, NULL)
157 #define wake_up_all(x)                  __wake_up(x, TASK_NORMAL, 0, NULL)
158 #define wake_up_locked(x)               __wake_up_locked((x), TASK_NORMAL)
159
160 #define wake_up_interruptible(x)        __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
161 #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
162 #define wake_up_interruptible_all(x)    __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
163 #define wake_up_interruptible_sync(x)   __wake_up_sync((x), TASK_INTERRUPTIBLE, 1)
164
165 #ifdef CONFIG_DEBUG_LOCK_ALLOC
166 /*
167  * macro to avoid include hell
168  */
169 #define wake_up_nested(x, s)                                            \
170 do {                                                                    \
171         unsigned long flags;                                            \
172                                                                         \
173         spin_lock_irqsave_nested(&(x)->lock, flags, (s));               \
174         wake_up_locked(x);                                              \
175         spin_unlock_irqrestore(&(x)->lock, flags);                      \
176 } while (0)
177 #else
178 #define wake_up_nested(x, s)            wake_up(x)
179 #endif
180
181 #define __wait_event(wq, condition)                                     \
182 do {                                                                    \
183         DEFINE_WAIT(__wait);                                            \
184                                                                         \
185         for (;;) {                                                      \
186                 prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE);    \
187                 if (condition)                                          \
188                         break;                                          \
189                 schedule();                                             \
190         }                                                               \
191         finish_wait(&wq, &__wait);                                      \
192 } while (0)
193
194 /**
195  * wait_event - sleep until a condition gets true
196  * @wq: the waitqueue to wait on
197  * @condition: a C expression for the event to wait for
198  *
199  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
200  * @condition evaluates to true. The @condition is checked each time
201  * the waitqueue @wq is woken up.
202  *
203  * wake_up() has to be called after changing any variable that could
204  * change the result of the wait condition.
205  */
206 #define wait_event(wq, condition)                                       \
207 do {                                                                    \
208         if (condition)                                                  \
209                 break;                                                  \
210         __wait_event(wq, condition);                                    \
211 } while (0)
212
213 #define __wait_event_timeout(wq, condition, ret)                        \
214 do {                                                                    \
215         DEFINE_WAIT(__wait);                                            \
216                                                                         \
217         for (;;) {                                                      \
218                 prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE);    \
219                 if (condition)                                          \
220                         break;                                          \
221                 ret = schedule_timeout(ret);                            \
222                 if (!ret)                                               \
223                         break;                                          \
224         }                                                               \
225         finish_wait(&wq, &__wait);                                      \
226 } while (0)
227
228 /**
229  * wait_event_timeout - sleep until a condition gets true or a timeout elapses
230  * @wq: the waitqueue to wait on
231  * @condition: a C expression for the event to wait for
232  * @timeout: timeout, in jiffies
233  *
234  * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
235  * @condition evaluates to true. The @condition is checked each time
236  * the waitqueue @wq is woken up.
237  *
238  * wake_up() has to be called after changing any variable that could
239  * change the result of the wait condition.
240  *
241  * The function returns 0 if the @timeout elapsed, and the remaining
242  * jiffies if the condition evaluated to true before the timeout elapsed.
243  */
244 #define wait_event_timeout(wq, condition, timeout)                      \
245 ({                                                                      \
246         long __ret = timeout;                                           \
247         if (!(condition))                                               \
248                 __wait_event_timeout(wq, condition, __ret);             \
249         __ret;                                                          \
250 })
251
252 #define __wait_event_interruptible(wq, condition, ret)                  \
253 do {                                                                    \
254         DEFINE_WAIT(__wait);                                            \
255                                                                         \
256         for (;;) {                                                      \
257                 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);      \
258                 if (condition)                                          \
259                         break;                                          \
260                 if (!signal_pending(current)) {                         \
261                         schedule();                                     \
262                         continue;                                       \
263                 }                                                       \
264                 ret = -ERESTARTSYS;                                     \
265                 break;                                                  \
266         }                                                               \
267         finish_wait(&wq, &__wait);                                      \
268 } while (0)
269
270 /**
271  * wait_event_interruptible - sleep until a condition gets true
272  * @wq: the waitqueue to wait on
273  * @condition: a C expression for the event to wait for
274  *
275  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
276  * @condition evaluates to true or a signal is received.
277  * The @condition is checked each time the waitqueue @wq is woken up.
278  *
279  * wake_up() has to be called after changing any variable that could
280  * change the result of the wait condition.
281  *
282  * The function will return -ERESTARTSYS if it was interrupted by a
283  * signal and 0 if @condition evaluated to true.
284  */
285 #define wait_event_interruptible(wq, condition)                         \
286 ({                                                                      \
287         int __ret = 0;                                                  \
288         if (!(condition))                                               \
289                 __wait_event_interruptible(wq, condition, __ret);       \
290         __ret;                                                          \
291 })
292
293 #define __wait_event_interruptible_timeout(wq, condition, ret)          \
294 do {                                                                    \
295         DEFINE_WAIT(__wait);                                            \
296                                                                         \
297         for (;;) {                                                      \
298                 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);      \
299                 if (condition)                                          \
300                         break;                                          \
301                 if (!signal_pending(current)) {                         \
302                         ret = schedule_timeout(ret);                    \
303                         if (!ret)                                       \
304                                 break;                                  \
305                         continue;                                       \
306                 }                                                       \
307                 ret = -ERESTARTSYS;                                     \
308                 break;                                                  \
309         }                                                               \
310         finish_wait(&wq, &__wait);                                      \
311 } while (0)
312
313 /**
314  * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
315  * @wq: the waitqueue to wait on
316  * @condition: a C expression for the event to wait for
317  * @timeout: timeout, in jiffies
318  *
319  * The process is put to sleep (TASK_INTERRUPTIBLE) until the
320  * @condition evaluates to true or a signal is received.
321  * The @condition is checked each time the waitqueue @wq is woken up.
322  *
323  * wake_up() has to be called after changing any variable that could
324  * change the result of the wait condition.
325  *
326  * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
327  * was interrupted by a signal, and the remaining jiffies otherwise
328  * if the condition evaluated to true before the timeout elapsed.
329  */
330 #define wait_event_interruptible_timeout(wq, condition, timeout)        \
331 ({                                                                      \
332         long __ret = timeout;                                           \
333         if (!(condition))                                               \
334                 __wait_event_interruptible_timeout(wq, condition, __ret); \
335         __ret;                                                          \
336 })
337
338 #define __wait_event_interruptible_exclusive(wq, condition, ret)        \
339 do {                                                                    \
340         DEFINE_WAIT(__wait);                                            \
341                                                                         \
342         for (;;) {                                                      \
343                 prepare_to_wait_exclusive(&wq, &__wait,                 \
344                                         TASK_INTERRUPTIBLE);            \
345                 if (condition)                                          \
346                         break;                                          \
347                 if (!signal_pending(current)) {                         \
348                         schedule();                                     \
349                         continue;                                       \
350                 }                                                       \
351                 ret = -ERESTARTSYS;                                     \
352                 break;                                                  \
353         }                                                               \
354         finish_wait(&wq, &__wait);                                      \
355 } while (0)
356
357 #define wait_event_interruptible_exclusive(wq, condition)               \
358 ({                                                                      \
359         int __ret = 0;                                                  \
360         if (!(condition))                                               \
361                 __wait_event_interruptible_exclusive(wq, condition, __ret);\
362         __ret;                                                          \
363 })
364
365 #define __wait_event_killable(wq, condition, ret)                       \
366 do {                                                                    \
367         DEFINE_WAIT(__wait);                                            \
368                                                                         \
369         for (;;) {                                                      \
370                 prepare_to_wait(&wq, &__wait, TASK_KILLABLE);           \
371                 if (condition)                                          \
372                         break;                                          \
373                 if (!fatal_signal_pending(current)) {                   \
374                         schedule();                                     \
375                         continue;                                       \
376                 }                                                       \
377                 ret = -ERESTARTSYS;                                     \
378                 break;                                                  \
379         }                                                               \
380         finish_wait(&wq, &__wait);                                      \
381 } while (0)
382
383 /**
384  * wait_event_killable - sleep until a condition gets true
385  * @wq: the waitqueue to wait on
386  * @condition: a C expression for the event to wait for
387  *
388  * The process is put to sleep (TASK_KILLABLE) until the
389  * @condition evaluates to true or a signal is received.
390  * The @condition is checked each time the waitqueue @wq is woken up.
391  *
392  * wake_up() has to be called after changing any variable that could
393  * change the result of the wait condition.
394  *
395  * The function will return -ERESTARTSYS if it was interrupted by a
396  * signal and 0 if @condition evaluated to true.
397  */
398 #define wait_event_killable(wq, condition)                              \
399 ({                                                                      \
400         int __ret = 0;                                                  \
401         if (!(condition))                                               \
402                 __wait_event_killable(wq, condition, __ret);            \
403         __ret;                                                          \
404 })
405
406 /*
407  * Must be called with the spinlock in the wait_queue_head_t held.
408  */
409 static inline void add_wait_queue_exclusive_locked(wait_queue_head_t *q,
410                                                    wait_queue_t * wait)
411 {
412         wait->flags |= WQ_FLAG_EXCLUSIVE;
413         __add_wait_queue_tail(q,  wait);
414 }
415
416 /*
417  * Must be called with the spinlock in the wait_queue_head_t held.
418  */
419 static inline void remove_wait_queue_locked(wait_queue_head_t *q,
420                                             wait_queue_t * wait)
421 {
422         __remove_wait_queue(q,  wait);
423 }
424
425 /*
426  * These are the old interfaces to sleep waiting for an event.
427  * They are racy.  DO NOT use them, use the wait_event* interfaces above.
428  * We plan to remove these interfaces.
429  */
430 extern void sleep_on(wait_queue_head_t *q);
431 extern long sleep_on_timeout(wait_queue_head_t *q,
432                                       signed long timeout);
433 extern void interruptible_sleep_on(wait_queue_head_t *q);
434 extern long interruptible_sleep_on_timeout(wait_queue_head_t *q,
435                                            signed long timeout);
436
437 /*
438  * Waitqueues which are removed from the waitqueue_head at wakeup time
439  */
440 void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state);
441 void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state);
442 void finish_wait(wait_queue_head_t *q, wait_queue_t *wait);
443 int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
444 int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
445
446 #define DEFINE_WAIT(name)                                               \
447         wait_queue_t name = {                                           \
448                 .private        = current,                              \
449                 .func           = autoremove_wake_function,             \
450                 .task_list      = LIST_HEAD_INIT((name).task_list),     \
451         }
452
453 #define DEFINE_WAIT_BIT(name, word, bit)                                \
454         struct wait_bit_queue name = {                                  \
455                 .key = __WAIT_BIT_KEY_INITIALIZER(word, bit),           \
456                 .wait   = {                                             \
457                         .private        = current,                      \
458                         .func           = wake_bit_function,            \
459                         .task_list      =                               \
460                                 LIST_HEAD_INIT((name).wait.task_list),  \
461                 },                                                      \
462         }
463
464 #define init_wait(wait)                                                 \
465         do {                                                            \
466                 (wait)->private = current;                              \
467                 (wait)->func = autoremove_wake_function;                \
468                 INIT_LIST_HEAD(&(wait)->task_list);                     \
469         } while (0)
470
471 /**
472  * wait_on_bit - wait for a bit to be cleared
473  * @word: the word being waited on, a kernel virtual address
474  * @bit: the bit of the word being waited on
475  * @action: the function used to sleep, which may take special actions
476  * @mode: the task state to sleep in
477  *
478  * There is a standard hashed waitqueue table for generic use. This
479  * is the part of the hashtable's accessor API that waits on a bit.
480  * For instance, if one were to have waiters on a bitflag, one would
481  * call wait_on_bit() in threads waiting for the bit to clear.
482  * One uses wait_on_bit() where one is waiting for the bit to clear,
483  * but has no intention of setting it.
484  */
485 static inline int wait_on_bit(void *word, int bit,
486                                 int (*action)(void *), unsigned mode)
487 {
488         if (!test_bit(bit, word))
489                 return 0;
490         return out_of_line_wait_on_bit(word, bit, action, mode);
491 }
492
493 /**
494  * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
495  * @word: the word being waited on, a kernel virtual address
496  * @bit: the bit of the word being waited on
497  * @action: the function used to sleep, which may take special actions
498  * @mode: the task state to sleep in
499  *
500  * There is a standard hashed waitqueue table for generic use. This
501  * is the part of the hashtable's accessor API that waits on a bit
502  * when one intends to set it, for instance, trying to lock bitflags.
503  * For instance, if one were to have waiters trying to set bitflag
504  * and waiting for it to clear before setting it, one would call
505  * wait_on_bit() in threads waiting to be able to set the bit.
506  * One uses wait_on_bit_lock() where one is waiting for the bit to
507  * clear with the intention of setting it, and when done, clearing it.
508  */
509 static inline int wait_on_bit_lock(void *word, int bit,
510                                 int (*action)(void *), unsigned mode)
511 {
512         if (!test_and_set_bit(bit, word))
513                 return 0;
514         return out_of_line_wait_on_bit_lock(word, bit, action, mode);
515 }
516         
517 #endif /* __KERNEL__ */
518
519 #endif