2 * linux/kernel/posix_timers.c
5 * 2002-10-15 Posix Clocks & timers
6 * by George Anzinger george@mvista.com
8 * Copyright (C) 2002 2003 by MontaVista Software.
10 * 2004-06-01 Fix CLOCK_REALTIME clock/timer TIMER_ABSTIME bug.
11 * Copyright (C) 2004 Boris Hu
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27 * MontaVista Software | 1237 East Arques Avenue | Sunnyvale | CA 94085 | USA
30 /* These are all the functions necessary to implement
31 * POSIX clocks & timers
34 #include <linux/smp_lock.h>
35 #include <linux/interrupt.h>
36 #include <linux/slab.h>
37 #include <linux/time.h>
38 #include <linux/mutex.h>
40 #include <asm/uaccess.h>
41 #include <asm/semaphore.h>
42 #include <linux/list.h>
43 #include <linux/init.h>
44 #include <linux/compiler.h>
45 #include <linux/idr.h>
46 #include <linux/posix-timers.h>
47 #include <linux/syscalls.h>
48 #include <linux/wait.h>
49 #include <linux/workqueue.h>
50 #include <linux/module.h>
53 * Management arrays for POSIX timers. Timers are kept in slab memory
54 * Timer ids are allocated by an external routine that keeps track of the
55 * id and the timer. The external interface is:
57 * void *idr_find(struct idr *idp, int id); to find timer_id <id>
58 * int idr_get_new(struct idr *idp, void *ptr); to get a new id and
60 * void idr_remove(struct idr *idp, int id); to release <id>
61 * void idr_init(struct idr *idp); to initialize <idp>
63 * The idr_get_new *may* call slab for more memory so it must not be
64 * called under a spin lock. Likewise idr_remore may release memory
65 * (but it may be ok to do this under a lock...).
66 * idr_find is just a memory look up and is quite fast. A -1 return
67 * indicates that the requested id does not exist.
71 * Lets keep our timers in a slab cache :-)
73 static kmem_cache_t
*posix_timers_cache
;
74 static struct idr posix_timers_id
;
75 static DEFINE_SPINLOCK(idr_lock
);
78 * we assume that the new SIGEV_THREAD_ID shares no bits with the other
79 * SIGEV values. Here we put out an error if this assumption fails.
81 #if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
82 ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
83 #error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
88 * The timer ID is turned into a timer address by idr_find().
89 * Verifying a valid ID consists of:
91 * a) checking that idr_find() returns other than -1.
92 * b) checking that the timer id matches the one in the timer itself.
93 * c) that the timer owner is in the callers thread group.
97 * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
98 * to implement others. This structure defines the various
99 * clocks and allows the possibility of adding others. We
100 * provide an interface to add clocks to the table and expect
101 * the "arch" code to add at least one clock that is high
102 * resolution. Here we define the standard CLOCK_REALTIME as a
103 * 1/HZ resolution clock.
105 * RESOLUTION: Clock resolution is used to round up timer and interval
106 * times, NOT to report clock times, which are reported with as
107 * much resolution as the system can muster. In some cases this
108 * resolution may depend on the underlying clock hardware and
109 * may not be quantifiable until run time, and only then is the
110 * necessary code is written. The standard says we should say
111 * something about this issue in the documentation...
113 * FUNCTIONS: The CLOCKs structure defines possible functions to handle
114 * various clock functions. For clocks that use the standard
115 * system timer code these entries should be NULL. This will
116 * allow dispatch without the overhead of indirect function
117 * calls. CLOCKS that depend on other sources (e.g. WWV or GPS)
118 * must supply functions here, even if the function just returns
119 * ENOSYS. The standard POSIX timer management code assumes the
120 * following: 1.) The k_itimer struct (sched.h) is used for the
121 * timer. 2.) The list, it_lock, it_clock, it_id and it_process
122 * fields are not modified by timer code.
124 * At this time all functions EXCEPT clock_nanosleep can be
125 * redirected by the CLOCKS structure. Clock_nanosleep is in
126 * there, but the code ignores it.
128 * Permissions: It is assumed that the clock_settime() function defined
129 * for each clock will take care of permission checks. Some
130 * clocks may be set able by any user (i.e. local process
131 * clocks) others not. Currently the only set able clock we
132 * have is CLOCK_REALTIME and its high res counter part, both of
133 * which we beg off on and pass to do_sys_settimeofday().
136 static struct k_clock posix_clocks
[MAX_CLOCKS
];
139 * These ones are defined below.
141 static int common_nsleep(const clockid_t
, int flags
, struct timespec
*t
,
142 struct timespec __user
*rmtp
);
143 static void common_timer_get(struct k_itimer
*, struct itimerspec
*);
144 static int common_timer_set(struct k_itimer
*, int,
145 struct itimerspec
*, struct itimerspec
*);
146 static int common_timer_del(struct k_itimer
*timer
);
148 static int posix_timer_fn(struct hrtimer
*data
);
150 static struct k_itimer
*lock_timer(timer_t timer_id
, unsigned long *flags
);
152 static inline void unlock_timer(struct k_itimer
*timr
, unsigned long flags
)
154 spin_unlock_irqrestore(&timr
->it_lock
, flags
);
158 * Call the k_clock hook function if non-null, or the default function.
160 #define CLOCK_DISPATCH(clock, call, arglist) \
161 ((clock) < 0 ? posix_cpu_##call arglist : \
162 (posix_clocks[clock].call != NULL \
163 ? (*posix_clocks[clock].call) arglist : common_##call arglist))
166 * Default clock hook functions when the struct k_clock passed
167 * to register_posix_clock leaves a function pointer null.
169 * The function common_CALL is the default implementation for
170 * the function pointer CALL in struct k_clock.
173 static inline int common_clock_getres(const clockid_t which_clock
,
177 tp
->tv_nsec
= posix_clocks
[which_clock
].res
;
182 * Get real time for posix timers
184 static int common_clock_get(clockid_t which_clock
, struct timespec
*tp
)
186 ktime_get_real_ts(tp
);
190 static inline int common_clock_set(const clockid_t which_clock
,
193 return do_sys_settimeofday(tp
, NULL
);
196 static int common_timer_create(struct k_itimer
*new_timer
)
198 hrtimer_init(&new_timer
->it
.real
.timer
, new_timer
->it_clock
, 0);
203 * Return nonzero if we know a priori this clockid_t value is bogus.
205 static inline int invalid_clockid(const clockid_t which_clock
)
207 if (which_clock
< 0) /* CPU clock, posix_cpu_* will check it */
209 if ((unsigned) which_clock
>= MAX_CLOCKS
)
211 if (posix_clocks
[which_clock
].clock_getres
!= NULL
)
213 if (posix_clocks
[which_clock
].res
!= 0)
219 * Get monotonic time for posix timers
221 static int posix_ktime_get_ts(clockid_t which_clock
, struct timespec
*tp
)
228 * Initialize everything, well, just everything in Posix clocks/timers ;)
230 static __init
int init_posix_timers(void)
232 struct k_clock clock_realtime
= {
233 .clock_getres
= hrtimer_get_res
,
235 struct k_clock clock_monotonic
= {
236 .clock_getres
= hrtimer_get_res
,
237 .clock_get
= posix_ktime_get_ts
,
238 .clock_set
= do_posix_clock_nosettime
,
241 register_posix_clock(CLOCK_REALTIME
, &clock_realtime
);
242 register_posix_clock(CLOCK_MONOTONIC
, &clock_monotonic
);
244 posix_timers_cache
= kmem_cache_create("posix_timers_cache",
245 sizeof (struct k_itimer
), 0, 0, NULL
, NULL
);
246 idr_init(&posix_timers_id
);
250 __initcall(init_posix_timers
);
252 static void schedule_next_timer(struct k_itimer
*timr
)
254 struct hrtimer
*timer
= &timr
->it
.real
.timer
;
256 if (timr
->it
.real
.interval
.tv64
== 0)
259 timr
->it_overrun
+= hrtimer_forward(timer
, timer
->base
->get_time(),
260 timr
->it
.real
.interval
);
262 timr
->it_overrun_last
= timr
->it_overrun
;
263 timr
->it_overrun
= -1;
264 ++timr
->it_requeue_pending
;
265 hrtimer_restart(timer
);
269 * This function is exported for use by the signal deliver code. It is
270 * called just prior to the info block being released and passes that
271 * block to us. It's function is to update the overrun entry AND to
272 * restart the timer. It should only be called if the timer is to be
273 * restarted (i.e. we have flagged this in the sys_private entry of the
276 * To protect aginst the timer going away while the interrupt is queued,
277 * we require that the it_requeue_pending flag be set.
279 void do_schedule_next_timer(struct siginfo
*info
)
281 struct k_itimer
*timr
;
284 timr
= lock_timer(info
->si_tid
, &flags
);
286 if (timr
&& timr
->it_requeue_pending
== info
->si_sys_private
) {
287 if (timr
->it_clock
< 0)
288 posix_cpu_timer_schedule(timr
);
290 schedule_next_timer(timr
);
292 info
->si_overrun
= timr
->it_overrun_last
;
296 unlock_timer(timr
, flags
);
299 int posix_timer_event(struct k_itimer
*timr
,int si_private
)
301 memset(&timr
->sigq
->info
, 0, sizeof(siginfo_t
));
302 timr
->sigq
->info
.si_sys_private
= si_private
;
303 /* Send signal to the process that owns this timer.*/
305 timr
->sigq
->info
.si_signo
= timr
->it_sigev_signo
;
306 timr
->sigq
->info
.si_errno
= 0;
307 timr
->sigq
->info
.si_code
= SI_TIMER
;
308 timr
->sigq
->info
.si_tid
= timr
->it_id
;
309 timr
->sigq
->info
.si_value
= timr
->it_sigev_value
;
311 if (timr
->it_sigev_notify
& SIGEV_THREAD_ID
) {
312 struct task_struct
*leader
;
313 int ret
= send_sigqueue(timr
->it_sigev_signo
, timr
->sigq
,
316 if (likely(ret
>= 0))
319 timr
->it_sigev_notify
= SIGEV_SIGNAL
;
320 leader
= timr
->it_process
->group_leader
;
321 put_task_struct(timr
->it_process
);
322 timr
->it_process
= leader
;
325 return send_group_sigqueue(timr
->it_sigev_signo
, timr
->sigq
,
328 EXPORT_SYMBOL_GPL(posix_timer_event
);
331 * This function gets called when a POSIX.1b interval timer expires. It
332 * is used as a callback from the kernel internal timer. The
333 * run_timer_list code ALWAYS calls with interrupts on.
335 * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
337 static int posix_timer_fn(struct hrtimer
*timer
)
339 struct k_itimer
*timr
;
342 int ret
= HRTIMER_NORESTART
;
344 timr
= container_of(timer
, struct k_itimer
, it
.real
.timer
);
345 spin_lock_irqsave(&timr
->it_lock
, flags
);
347 if (timr
->it
.real
.interval
.tv64
!= 0)
348 si_private
= ++timr
->it_requeue_pending
;
350 if (posix_timer_event(timr
, si_private
)) {
352 * signal was not sent because of sig_ignor
353 * we will not get a call back to restart it AND
354 * it should be restarted.
356 if (timr
->it
.real
.interval
.tv64
!= 0) {
358 hrtimer_forward(timer
,
359 timer
->base
->softirq_time
,
360 timr
->it
.real
.interval
);
361 ret
= HRTIMER_RESTART
;
362 ++timr
->it_requeue_pending
;
366 unlock_timer(timr
, flags
);
370 static struct task_struct
* good_sigevent(sigevent_t
* event
)
372 struct task_struct
*rtn
= current
->group_leader
;
374 if ((event
->sigev_notify
& SIGEV_THREAD_ID
) &&
375 (!(rtn
= find_task_by_pid(event
->sigev_notify_thread_id
)) ||
376 rtn
->tgid
!= current
->tgid
||
377 (event
->sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_SIGNAL
))
380 if (((event
->sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
) &&
381 ((event
->sigev_signo
<= 0) || (event
->sigev_signo
> SIGRTMAX
)))
387 void register_posix_clock(const clockid_t clock_id
, struct k_clock
*new_clock
)
389 if ((unsigned) clock_id
>= MAX_CLOCKS
) {
390 printk("POSIX clock register failed for clock_id %d\n",
395 posix_clocks
[clock_id
] = *new_clock
;
397 EXPORT_SYMBOL_GPL(register_posix_clock
);
399 static struct k_itimer
* alloc_posix_timer(void)
401 struct k_itimer
*tmr
;
402 tmr
= kmem_cache_alloc(posix_timers_cache
, GFP_KERNEL
);
405 memset(tmr
, 0, sizeof (struct k_itimer
));
406 if (unlikely(!(tmr
->sigq
= sigqueue_alloc()))) {
407 kmem_cache_free(posix_timers_cache
, tmr
);
414 #define IT_ID_NOT_SET 0
415 static void release_posix_timer(struct k_itimer
*tmr
, int it_id_set
)
419 spin_lock_irqsave(&idr_lock
, flags
);
420 idr_remove(&posix_timers_id
, tmr
->it_id
);
421 spin_unlock_irqrestore(&idr_lock
, flags
);
423 sigqueue_free(tmr
->sigq
);
424 if (unlikely(tmr
->it_process
) &&
425 tmr
->it_sigev_notify
== (SIGEV_SIGNAL
|SIGEV_THREAD_ID
))
426 put_task_struct(tmr
->it_process
);
427 kmem_cache_free(posix_timers_cache
, tmr
);
430 /* Create a POSIX.1b interval timer. */
433 sys_timer_create(const clockid_t which_clock
,
434 struct sigevent __user
*timer_event_spec
,
435 timer_t __user
* created_timer_id
)
438 struct k_itimer
*new_timer
= NULL
;
440 struct task_struct
*process
= NULL
;
443 int it_id_set
= IT_ID_NOT_SET
;
445 if (invalid_clockid(which_clock
))
448 new_timer
= alloc_posix_timer();
449 if (unlikely(!new_timer
))
452 spin_lock_init(&new_timer
->it_lock
);
454 if (unlikely(!idr_pre_get(&posix_timers_id
, GFP_KERNEL
))) {
458 spin_lock_irq(&idr_lock
);
459 error
= idr_get_new(&posix_timers_id
, (void *) new_timer
,
461 spin_unlock_irq(&idr_lock
);
462 if (error
== -EAGAIN
)
466 * Wierd looking, but we return EAGAIN if the IDR is
467 * full (proper POSIX return value for this)
473 it_id_set
= IT_ID_SET
;
474 new_timer
->it_id
= (timer_t
) new_timer_id
;
475 new_timer
->it_clock
= which_clock
;
476 new_timer
->it_overrun
= -1;
477 error
= CLOCK_DISPATCH(which_clock
, timer_create
, (new_timer
));
482 * return the timer_id now. The next step is hard to
483 * back out if there is an error.
485 if (copy_to_user(created_timer_id
,
486 &new_timer_id
, sizeof (new_timer_id
))) {
490 if (timer_event_spec
) {
491 if (copy_from_user(&event
, timer_event_spec
, sizeof (event
))) {
495 new_timer
->it_sigev_notify
= event
.sigev_notify
;
496 new_timer
->it_sigev_signo
= event
.sigev_signo
;
497 new_timer
->it_sigev_value
= event
.sigev_value
;
499 read_lock(&tasklist_lock
);
500 if ((process
= good_sigevent(&event
))) {
502 * We may be setting up this process for another
503 * thread. It may be exiting. To catch this
504 * case the we check the PF_EXITING flag. If
505 * the flag is not set, the siglock will catch
506 * him before it is too late (in exit_itimers).
508 * The exec case is a bit more invloved but easy
509 * to code. If the process is in our thread
510 * group (and it must be or we would not allow
511 * it here) and is doing an exec, it will cause
512 * us to be killed. In this case it will wait
513 * for us to die which means we can finish this
514 * linkage with our last gasp. I.e. no code :)
516 spin_lock_irqsave(&process
->sighand
->siglock
, flags
);
517 if (!(process
->flags
& PF_EXITING
)) {
518 new_timer
->it_process
= process
;
519 list_add(&new_timer
->list
,
520 &process
->signal
->posix_timers
);
521 spin_unlock_irqrestore(&process
->sighand
->siglock
, flags
);
522 if (new_timer
->it_sigev_notify
== (SIGEV_SIGNAL
|SIGEV_THREAD_ID
))
523 get_task_struct(process
);
525 spin_unlock_irqrestore(&process
->sighand
->siglock
, flags
);
529 read_unlock(&tasklist_lock
);
535 new_timer
->it_sigev_notify
= SIGEV_SIGNAL
;
536 new_timer
->it_sigev_signo
= SIGALRM
;
537 new_timer
->it_sigev_value
.sival_int
= new_timer
->it_id
;
538 process
= current
->group_leader
;
539 spin_lock_irqsave(&process
->sighand
->siglock
, flags
);
540 new_timer
->it_process
= process
;
541 list_add(&new_timer
->list
, &process
->signal
->posix_timers
);
542 spin_unlock_irqrestore(&process
->sighand
->siglock
, flags
);
546 * In the case of the timer belonging to another task, after
547 * the task is unlocked, the timer is owned by the other task
548 * and may cease to exist at any time. Don't use or modify
549 * new_timer after the unlock call.
554 release_posix_timer(new_timer
, it_id_set
);
560 * Locking issues: We need to protect the result of the id look up until
561 * we get the timer locked down so it is not deleted under us. The
562 * removal is done under the idr spinlock so we use that here to bridge
563 * the find to the timer lock. To avoid a dead lock, the timer id MUST
564 * be release with out holding the timer lock.
566 static struct k_itimer
* lock_timer(timer_t timer_id
, unsigned long *flags
)
568 struct k_itimer
*timr
;
570 * Watch out here. We do a irqsave on the idr_lock and pass the
571 * flags part over to the timer lock. Must not let interrupts in
572 * while we are moving the lock.
575 spin_lock_irqsave(&idr_lock
, *flags
);
576 timr
= (struct k_itimer
*) idr_find(&posix_timers_id
, (int) timer_id
);
578 spin_lock(&timr
->it_lock
);
579 spin_unlock(&idr_lock
);
581 if ((timr
->it_id
!= timer_id
) || !(timr
->it_process
) ||
582 timr
->it_process
->tgid
!= current
->tgid
) {
583 unlock_timer(timr
, *flags
);
587 spin_unlock_irqrestore(&idr_lock
, *flags
);
593 * Get the time remaining on a POSIX.1b interval timer. This function
594 * is ALWAYS called with spin_lock_irq on the timer, thus it must not
597 * We have a couple of messes to clean up here. First there is the case
598 * of a timer that has a requeue pending. These timers should appear to
599 * be in the timer list with an expiry as if we were to requeue them
602 * The second issue is the SIGEV_NONE timer which may be active but is
603 * not really ever put in the timer list (to save system resources).
604 * This timer may be expired, and if so, we will do it here. Otherwise
605 * it is the same as a requeue pending timer WRT to what we should
609 common_timer_get(struct k_itimer
*timr
, struct itimerspec
*cur_setting
)
611 ktime_t now
, remaining
, iv
;
612 struct hrtimer
*timer
= &timr
->it
.real
.timer
;
614 memset(cur_setting
, 0, sizeof(struct itimerspec
));
616 iv
= timr
->it
.real
.interval
;
618 /* interval timer ? */
620 cur_setting
->it_interval
= ktime_to_timespec(iv
);
621 else if (!hrtimer_active(timer
) &&
622 (timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
)
625 now
= timer
->base
->get_time();
628 * When a requeue is pending or this is a SIGEV_NONE
629 * timer move the expiry time forward by intervals, so
632 if (iv
.tv64
&& (timr
->it_requeue_pending
& REQUEUE_PENDING
||
633 (timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) == SIGEV_NONE
))
634 timr
->it_overrun
+= hrtimer_forward(timer
, now
, iv
);
636 remaining
= ktime_sub(timer
->expires
, now
);
637 /* Return 0 only, when the timer is expired and not pending */
638 if (remaining
.tv64
<= 0) {
640 * A single shot SIGEV_NONE timer must return 0, when
643 if ((timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) != SIGEV_NONE
)
644 cur_setting
->it_value
.tv_nsec
= 1;
646 cur_setting
->it_value
= ktime_to_timespec(remaining
);
649 /* Get the time remaining on a POSIX.1b interval timer. */
651 sys_timer_gettime(timer_t timer_id
, struct itimerspec __user
*setting
)
653 struct k_itimer
*timr
;
654 struct itimerspec cur_setting
;
657 timr
= lock_timer(timer_id
, &flags
);
661 CLOCK_DISPATCH(timr
->it_clock
, timer_get
, (timr
, &cur_setting
));
663 unlock_timer(timr
, flags
);
665 if (copy_to_user(setting
, &cur_setting
, sizeof (cur_setting
)))
672 * Get the number of overruns of a POSIX.1b interval timer. This is to
673 * be the overrun of the timer last delivered. At the same time we are
674 * accumulating overruns on the next timer. The overrun is frozen when
675 * the signal is delivered, either at the notify time (if the info block
676 * is not queued) or at the actual delivery time (as we are informed by
677 * the call back to do_schedule_next_timer(). So all we need to do is
678 * to pick up the frozen overrun.
681 sys_timer_getoverrun(timer_t timer_id
)
683 struct k_itimer
*timr
;
687 timr
= lock_timer(timer_id
, &flags
);
691 overrun
= timr
->it_overrun_last
;
692 unlock_timer(timr
, flags
);
697 /* Set a POSIX.1b interval timer. */
698 /* timr->it_lock is taken. */
700 common_timer_set(struct k_itimer
*timr
, int flags
,
701 struct itimerspec
*new_setting
, struct itimerspec
*old_setting
)
703 struct hrtimer
*timer
= &timr
->it
.real
.timer
;
704 enum hrtimer_mode mode
;
707 common_timer_get(timr
, old_setting
);
709 /* disable the timer */
710 timr
->it
.real
.interval
.tv64
= 0;
712 * careful here. If smp we could be in the "fire" routine which will
713 * be spinning as we hold the lock. But this is ONLY an SMP issue.
715 if (hrtimer_try_to_cancel(timer
) < 0)
718 timr
->it_requeue_pending
= (timr
->it_requeue_pending
+ 2) &
720 timr
->it_overrun_last
= 0;
722 /* switch off the timer when it_value is zero */
723 if (!new_setting
->it_value
.tv_sec
&& !new_setting
->it_value
.tv_nsec
)
726 mode
= flags
& TIMER_ABSTIME
? HRTIMER_ABS
: HRTIMER_REL
;
727 hrtimer_init(&timr
->it
.real
.timer
, timr
->it_clock
, mode
);
728 timr
->it
.real
.timer
.function
= posix_timer_fn
;
730 timer
->expires
= timespec_to_ktime(new_setting
->it_value
);
732 /* Convert interval */
733 timr
->it
.real
.interval
= timespec_to_ktime(new_setting
->it_interval
);
735 /* SIGEV_NONE timers are not queued ! See common_timer_get */
736 if (((timr
->it_sigev_notify
& ~SIGEV_THREAD_ID
) == SIGEV_NONE
)) {
737 /* Setup correct expiry time for relative timers */
738 if (mode
== HRTIMER_REL
)
739 timer
->expires
= ktime_add(timer
->expires
,
740 timer
->base
->get_time());
744 hrtimer_start(timer
, timer
->expires
, mode
);
748 /* Set a POSIX.1b interval timer */
750 sys_timer_settime(timer_t timer_id
, int flags
,
751 const struct itimerspec __user
*new_setting
,
752 struct itimerspec __user
*old_setting
)
754 struct k_itimer
*timr
;
755 struct itimerspec new_spec
, old_spec
;
758 struct itimerspec
*rtn
= old_setting
? &old_spec
: NULL
;
763 if (copy_from_user(&new_spec
, new_setting
, sizeof (new_spec
)))
766 if (!timespec_valid(&new_spec
.it_interval
) ||
767 !timespec_valid(&new_spec
.it_value
))
770 timr
= lock_timer(timer_id
, &flag
);
774 error
= CLOCK_DISPATCH(timr
->it_clock
, timer_set
,
775 (timr
, flags
, &new_spec
, rtn
));
777 unlock_timer(timr
, flag
);
778 if (error
== TIMER_RETRY
) {
779 rtn
= NULL
; // We already got the old time...
783 if (old_setting
&& !error
&&
784 copy_to_user(old_setting
, &old_spec
, sizeof (old_spec
)))
790 static inline int common_timer_del(struct k_itimer
*timer
)
792 timer
->it
.real
.interval
.tv64
= 0;
794 if (hrtimer_try_to_cancel(&timer
->it
.real
.timer
) < 0)
799 static inline int timer_delete_hook(struct k_itimer
*timer
)
801 return CLOCK_DISPATCH(timer
->it_clock
, timer_del
, (timer
));
804 /* Delete a POSIX.1b interval timer. */
806 sys_timer_delete(timer_t timer_id
)
808 struct k_itimer
*timer
;
812 timer
= lock_timer(timer_id
, &flags
);
816 if (timer_delete_hook(timer
) == TIMER_RETRY
) {
817 unlock_timer(timer
, flags
);
821 spin_lock(¤t
->sighand
->siglock
);
822 list_del(&timer
->list
);
823 spin_unlock(¤t
->sighand
->siglock
);
825 * This keeps any tasks waiting on the spin lock from thinking
826 * they got something (see the lock code above).
828 if (timer
->it_process
) {
829 if (timer
->it_sigev_notify
== (SIGEV_SIGNAL
|SIGEV_THREAD_ID
))
830 put_task_struct(timer
->it_process
);
831 timer
->it_process
= NULL
;
833 unlock_timer(timer
, flags
);
834 release_posix_timer(timer
, IT_ID_SET
);
839 * return timer owned by the process, used by exit_itimers
841 static void itimer_delete(struct k_itimer
*timer
)
846 spin_lock_irqsave(&timer
->it_lock
, flags
);
848 if (timer_delete_hook(timer
) == TIMER_RETRY
) {
849 unlock_timer(timer
, flags
);
852 list_del(&timer
->list
);
854 * This keeps any tasks waiting on the spin lock from thinking
855 * they got something (see the lock code above).
857 if (timer
->it_process
) {
858 if (timer
->it_sigev_notify
== (SIGEV_SIGNAL
|SIGEV_THREAD_ID
))
859 put_task_struct(timer
->it_process
);
860 timer
->it_process
= NULL
;
862 unlock_timer(timer
, flags
);
863 release_posix_timer(timer
, IT_ID_SET
);
867 * This is called by do_exit or de_thread, only when there are no more
868 * references to the shared signal_struct.
870 void exit_itimers(struct signal_struct
*sig
)
872 struct k_itimer
*tmr
;
874 while (!list_empty(&sig
->posix_timers
)) {
875 tmr
= list_entry(sig
->posix_timers
.next
, struct k_itimer
, list
);
880 /* Not available / possible... functions */
881 int do_posix_clock_nosettime(const clockid_t clockid
, struct timespec
*tp
)
885 EXPORT_SYMBOL_GPL(do_posix_clock_nosettime
);
887 int do_posix_clock_nonanosleep(const clockid_t clock
, int flags
,
888 struct timespec
*t
, struct timespec __user
*r
)
891 return -EOPNOTSUPP
; /* aka ENOTSUP in userland for POSIX */
892 #else /* parisc does define it separately. */
896 EXPORT_SYMBOL_GPL(do_posix_clock_nonanosleep
);
898 asmlinkage
long sys_clock_settime(const clockid_t which_clock
,
899 const struct timespec __user
*tp
)
901 struct timespec new_tp
;
903 if (invalid_clockid(which_clock
))
905 if (copy_from_user(&new_tp
, tp
, sizeof (*tp
)))
908 return CLOCK_DISPATCH(which_clock
, clock_set
, (which_clock
, &new_tp
));
912 sys_clock_gettime(const clockid_t which_clock
, struct timespec __user
*tp
)
914 struct timespec kernel_tp
;
917 if (invalid_clockid(which_clock
))
919 error
= CLOCK_DISPATCH(which_clock
, clock_get
,
920 (which_clock
, &kernel_tp
));
921 if (!error
&& copy_to_user(tp
, &kernel_tp
, sizeof (kernel_tp
)))
929 sys_clock_getres(const clockid_t which_clock
, struct timespec __user
*tp
)
931 struct timespec rtn_tp
;
934 if (invalid_clockid(which_clock
))
937 error
= CLOCK_DISPATCH(which_clock
, clock_getres
,
938 (which_clock
, &rtn_tp
));
940 if (!error
&& tp
&& copy_to_user(tp
, &rtn_tp
, sizeof (rtn_tp
))) {
948 * nanosleep for monotonic and realtime clocks
950 static int common_nsleep(const clockid_t which_clock
, int flags
,
951 struct timespec
*tsave
, struct timespec __user
*rmtp
)
953 return hrtimer_nanosleep(tsave
, rmtp
, flags
& TIMER_ABSTIME
?
954 HRTIMER_ABS
: HRTIMER_REL
, which_clock
);
958 sys_clock_nanosleep(const clockid_t which_clock
, int flags
,
959 const struct timespec __user
*rqtp
,
960 struct timespec __user
*rmtp
)
964 if (invalid_clockid(which_clock
))
967 if (copy_from_user(&t
, rqtp
, sizeof (struct timespec
)))
970 if (!timespec_valid(&t
))
973 return CLOCK_DISPATCH(which_clock
, nsleep
,
974 (which_clock
, flags
, &t
, rmtp
));