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/interrupt.h>
35 #include <linux/slab.h>
36 #include <linux/time.h>
37 #include <linux/mutex.h>
39 #include <asm/uaccess.h>
40 #include <linux/list.h>
41 #include <linux/init.h>
42 #include <linux/compiler.h>
43 #include <linux/idr.h>
44 #include <linux/posix-timers.h>
45 #include <linux/syscalls.h>
46 #include <linux/wait.h>
47 #include <linux/workqueue.h>
48 #include <linux/module.h>
51 * Management arrays for POSIX timers. Timers are kept in slab memory
52 * Timer ids are allocated by an external routine that keeps track of the
53 * id and the timer. The external interface is:
55 * void *idr_find(struct idr *idp, int id); to find timer_id <id>
56 * int idr_get_new(struct idr *idp, void *ptr); to get a new id and
58 * void idr_remove(struct idr *idp, int id); to release <id>
59 * void idr_init(struct idr *idp); to initialize <idp>
61 * The idr_get_new *may* call slab for more memory so it must not be
62 * called under a spin lock. Likewise idr_remore may release memory
63 * (but it may be ok to do this under a lock...).
64 * idr_find is just a memory look up and is quite fast. A -1 return
65 * indicates that the requested id does not exist.
69 * Lets keep our timers in a slab cache :-)
71 static struct kmem_cache *posix_timers_cache;
72 static struct idr posix_timers_id;
73 static DEFINE_SPINLOCK(idr_lock);
76 * we assume that the new SIGEV_THREAD_ID shares no bits with the other
77 * SIGEV values. Here we put out an error if this assumption fails.
79 #if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
80 ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
81 #error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
85 * parisc wants ENOTSUP instead of EOPNOTSUPP
88 # define ENANOSLEEP_NOTSUP EOPNOTSUPP
90 # define ENANOSLEEP_NOTSUP ENOTSUP
94 * The timer ID is turned into a timer address by idr_find().
95 * Verifying a valid ID consists of:
97 * a) checking that idr_find() returns other than -1.
98 * b) checking that the timer id matches the one in the timer itself.
99 * c) that the timer owner is in the callers thread group.
103 * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
104 * to implement others. This structure defines the various
107 * RESOLUTION: Clock resolution is used to round up timer and interval
108 * times, NOT to report clock times, which are reported with as
109 * much resolution as the system can muster. In some cases this
110 * resolution may depend on the underlying clock hardware and
111 * may not be quantifiable until run time, and only then is the
112 * necessary code is written. The standard says we should say
113 * something about this issue in the documentation...
115 * FUNCTIONS: The CLOCKs structure defines possible functions to
116 * handle various clock functions.
118 * The standard POSIX timer management code assumes the
119 * following: 1.) The k_itimer struct (sched.h) is used for
120 * the timer. 2.) The list, it_lock, it_clock, it_id and
121 * it_pid fields are not modified by timer code.
123 * Permissions: It is assumed that the clock_settime() function defined
124 * for each clock will take care of permission checks. Some
125 * clocks may be set able by any user (i.e. local process
126 * clocks) others not. Currently the only set able clock we
127 * have is CLOCK_REALTIME and its high res counter part, both of
128 * which we beg off on and pass to do_sys_settimeofday().
131 static struct k_clock posix_clocks[MAX_CLOCKS];
134 * These ones are defined below.
136 static int common_nsleep(const clockid_t, int flags, struct timespec *t,
137 struct timespec __user *rmtp);
138 static int common_timer_create(struct k_itimer *new_timer);
139 static void common_timer_get(struct k_itimer *, struct itimerspec *);
140 static int common_timer_set(struct k_itimer *, int,
141 struct itimerspec *, struct itimerspec *);
142 static int common_timer_del(struct k_itimer *timer);
144 static enum hrtimer_restart posix_timer_fn(struct hrtimer *data);
146 static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
148 #define lock_timer(tid, flags) \
149 ({ struct k_itimer *__timr; \
150 __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags)); \
154 static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
156 spin_unlock_irqrestore(&timr->it_lock, flags);
159 /* Get clock_realtime */
160 static int posix_clock_realtime_get(clockid_t which_clock, struct timespec *tp)
162 ktime_get_real_ts(tp);
166 /* Set clock_realtime */
167 static int posix_clock_realtime_set(const clockid_t which_clock,
168 const struct timespec *tp)
170 return do_sys_settimeofday(tp, NULL);
173 static int posix_clock_realtime_adj(const clockid_t which_clock,
176 return do_adjtimex(t);
180 * Get monotonic time for posix timers
182 static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp)
189 * Get monotonic time for posix timers
191 static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
198 static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp)
200 *tp = current_kernel_time();
204 static int posix_get_monotonic_coarse(clockid_t which_clock,
207 *tp = get_monotonic_coarse();
211 static int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp)
213 *tp = ktime_to_timespec(KTIME_LOW_RES);
217 * Initialize everything, well, just everything in Posix clocks/timers ;)
219 static __init int init_posix_timers(void)
221 struct k_clock clock_realtime = {
222 .clock_getres = hrtimer_get_res,
223 .clock_get = posix_clock_realtime_get,
224 .clock_set = posix_clock_realtime_set,
225 .clock_adj = posix_clock_realtime_adj,
226 .nsleep = common_nsleep,
227 .nsleep_restart = hrtimer_nanosleep_restart,
228 .timer_create = common_timer_create,
229 .timer_set = common_timer_set,
230 .timer_get = common_timer_get,
231 .timer_del = common_timer_del,
233 struct k_clock clock_monotonic = {
234 .clock_getres = hrtimer_get_res,
235 .clock_get = posix_ktime_get_ts,
236 .nsleep = common_nsleep,
237 .nsleep_restart = hrtimer_nanosleep_restart,
238 .timer_create = common_timer_create,
239 .timer_set = common_timer_set,
240 .timer_get = common_timer_get,
241 .timer_del = common_timer_del,
243 struct k_clock clock_monotonic_raw = {
244 .clock_getres = hrtimer_get_res,
245 .clock_get = posix_get_monotonic_raw,
247 struct k_clock clock_realtime_coarse = {
248 .clock_getres = posix_get_coarse_res,
249 .clock_get = posix_get_realtime_coarse,
251 struct k_clock clock_monotonic_coarse = {
252 .clock_getres = posix_get_coarse_res,
253 .clock_get = posix_get_monotonic_coarse,
256 register_posix_clock(CLOCK_REALTIME, &clock_realtime);
257 register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic);
258 register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
259 register_posix_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse);
260 register_posix_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse);
262 posix_timers_cache = kmem_cache_create("posix_timers_cache",
263 sizeof (struct k_itimer), 0, SLAB_PANIC,
265 idr_init(&posix_timers_id);
269 __initcall(init_posix_timers);
271 static void schedule_next_timer(struct k_itimer *timr)
273 struct hrtimer *timer = &timr->it.real.timer;
275 if (timr->it.real.interval.tv64 == 0)
278 timr->it_overrun += (unsigned int) hrtimer_forward(timer,
279 timer->base->get_time(),
280 timr->it.real.interval);
282 timr->it_overrun_last = timr->it_overrun;
283 timr->it_overrun = -1;
284 ++timr->it_requeue_pending;
285 hrtimer_restart(timer);
289 * This function is exported for use by the signal deliver code. It is
290 * called just prior to the info block being released and passes that
291 * block to us. It's function is to update the overrun entry AND to
292 * restart the timer. It should only be called if the timer is to be
293 * restarted (i.e. we have flagged this in the sys_private entry of the
296 * To protect aginst the timer going away while the interrupt is queued,
297 * we require that the it_requeue_pending flag be set.
299 void do_schedule_next_timer(struct siginfo *info)
301 struct k_itimer *timr;
304 timr = lock_timer(info->si_tid, &flags);
306 if (timr && timr->it_requeue_pending == info->si_sys_private) {
307 if (timr->it_clock < 0)
308 posix_cpu_timer_schedule(timr);
310 schedule_next_timer(timr);
312 info->si_overrun += timr->it_overrun_last;
316 unlock_timer(timr, flags);
319 int posix_timer_event(struct k_itimer *timr, int si_private)
321 struct task_struct *task;
322 int shared, ret = -1;
324 * FIXME: if ->sigq is queued we can race with
325 * dequeue_signal()->do_schedule_next_timer().
327 * If dequeue_signal() sees the "right" value of
328 * si_sys_private it calls do_schedule_next_timer().
329 * We re-queue ->sigq and drop ->it_lock().
330 * do_schedule_next_timer() locks the timer
331 * and re-schedules it while ->sigq is pending.
332 * Not really bad, but not that we want.
334 timr->sigq->info.si_sys_private = si_private;
337 task = pid_task(timr->it_pid, PIDTYPE_PID);
339 shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID);
340 ret = send_sigqueue(timr->sigq, task, shared);
343 /* If we failed to send the signal the timer stops. */
346 EXPORT_SYMBOL_GPL(posix_timer_event);
349 * This function gets called when a POSIX.1b interval timer expires. It
350 * is used as a callback from the kernel internal timer. The
351 * run_timer_list code ALWAYS calls with interrupts on.
353 * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
355 static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
357 struct k_itimer *timr;
360 enum hrtimer_restart ret = HRTIMER_NORESTART;
362 timr = container_of(timer, struct k_itimer, it.real.timer);
363 spin_lock_irqsave(&timr->it_lock, flags);
365 if (timr->it.real.interval.tv64 != 0)
366 si_private = ++timr->it_requeue_pending;
368 if (posix_timer_event(timr, si_private)) {
370 * signal was not sent because of sig_ignor
371 * we will not get a call back to restart it AND
372 * it should be restarted.
374 if (timr->it.real.interval.tv64 != 0) {
375 ktime_t now = hrtimer_cb_get_time(timer);
378 * FIXME: What we really want, is to stop this
379 * timer completely and restart it in case the
380 * SIG_IGN is removed. This is a non trivial
381 * change which involves sighand locking
382 * (sigh !), which we don't want to do late in
385 * For now we just let timers with an interval
386 * less than a jiffie expire every jiffie to
387 * avoid softirq starvation in case of SIG_IGN
388 * and a very small interval, which would put
389 * the timer right back on the softirq pending
390 * list. By moving now ahead of time we trick
391 * hrtimer_forward() to expire the timer
392 * later, while we still maintain the overrun
393 * accuracy, but have some inconsistency in
394 * the timer_gettime() case. This is at least
395 * better than a starved softirq. A more
396 * complex fix which solves also another related
397 * inconsistency is already in the pipeline.
399 #ifdef CONFIG_HIGH_RES_TIMERS
401 ktime_t kj = ktime_set(0, NSEC_PER_SEC / HZ);
403 if (timr->it.real.interval.tv64 < kj.tv64)
404 now = ktime_add(now, kj);
407 timr->it_overrun += (unsigned int)
408 hrtimer_forward(timer, now,
409 timr->it.real.interval);
410 ret = HRTIMER_RESTART;
411 ++timr->it_requeue_pending;
415 unlock_timer(timr, flags);
419 static struct pid *good_sigevent(sigevent_t * event)
421 struct task_struct *rtn = current->group_leader;
423 if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
424 (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
425 !same_thread_group(rtn, current) ||
426 (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
429 if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
430 ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
433 return task_pid(rtn);
436 void register_posix_clock(const clockid_t clock_id, struct k_clock *new_clock)
438 if ((unsigned) clock_id >= MAX_CLOCKS) {
439 printk(KERN_WARNING "POSIX clock register failed for clock_id %d\n",
444 if (!new_clock->clock_get) {
445 printk(KERN_WARNING "POSIX clock id %d lacks clock_get()\n",
449 if (!new_clock->clock_getres) {
450 printk(KERN_WARNING "POSIX clock id %d lacks clock_getres()\n",
455 posix_clocks[clock_id] = *new_clock;
457 EXPORT_SYMBOL_GPL(register_posix_clock);
459 static struct k_itimer * alloc_posix_timer(void)
461 struct k_itimer *tmr;
462 tmr = kmem_cache_zalloc(posix_timers_cache, GFP_KERNEL);
465 if (unlikely(!(tmr->sigq = sigqueue_alloc()))) {
466 kmem_cache_free(posix_timers_cache, tmr);
469 memset(&tmr->sigq->info, 0, sizeof(siginfo_t));
474 #define IT_ID_NOT_SET 0
475 static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
479 spin_lock_irqsave(&idr_lock, flags);
480 idr_remove(&posix_timers_id, tmr->it_id);
481 spin_unlock_irqrestore(&idr_lock, flags);
483 put_pid(tmr->it_pid);
484 sigqueue_free(tmr->sigq);
485 kmem_cache_free(posix_timers_cache, tmr);
488 static struct k_clock *clockid_to_kclock(const clockid_t id)
491 return &clock_posix_cpu;
493 if (id >= MAX_CLOCKS || !posix_clocks[id].clock_getres)
495 return &posix_clocks[id];
498 static int common_timer_create(struct k_itimer *new_timer)
500 hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
504 /* Create a POSIX.1b interval timer. */
506 SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
507 struct sigevent __user *, timer_event_spec,
508 timer_t __user *, created_timer_id)
510 struct k_clock *kc = clockid_to_kclock(which_clock);
511 struct k_itimer *new_timer;
512 int error, new_timer_id;
514 int it_id_set = IT_ID_NOT_SET;
518 if (!kc->timer_create)
521 new_timer = alloc_posix_timer();
522 if (unlikely(!new_timer))
525 spin_lock_init(&new_timer->it_lock);
527 if (unlikely(!idr_pre_get(&posix_timers_id, GFP_KERNEL))) {
531 spin_lock_irq(&idr_lock);
532 error = idr_get_new(&posix_timers_id, new_timer, &new_timer_id);
533 spin_unlock_irq(&idr_lock);
535 if (error == -EAGAIN)
538 * Weird looking, but we return EAGAIN if the IDR is
539 * full (proper POSIX return value for this)
545 it_id_set = IT_ID_SET;
546 new_timer->it_id = (timer_t) new_timer_id;
547 new_timer->it_clock = which_clock;
548 new_timer->it_overrun = -1;
550 if (timer_event_spec) {
551 if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
556 new_timer->it_pid = get_pid(good_sigevent(&event));
558 if (!new_timer->it_pid) {
563 event.sigev_notify = SIGEV_SIGNAL;
564 event.sigev_signo = SIGALRM;
565 event.sigev_value.sival_int = new_timer->it_id;
566 new_timer->it_pid = get_pid(task_tgid(current));
569 new_timer->it_sigev_notify = event.sigev_notify;
570 new_timer->sigq->info.si_signo = event.sigev_signo;
571 new_timer->sigq->info.si_value = event.sigev_value;
572 new_timer->sigq->info.si_tid = new_timer->it_id;
573 new_timer->sigq->info.si_code = SI_TIMER;
575 if (copy_to_user(created_timer_id,
576 &new_timer_id, sizeof (new_timer_id))) {
581 error = kc->timer_create(new_timer);
585 spin_lock_irq(¤t->sighand->siglock);
586 new_timer->it_signal = current->signal;
587 list_add(&new_timer->list, ¤t->signal->posix_timers);
588 spin_unlock_irq(¤t->sighand->siglock);
592 * In the case of the timer belonging to another task, after
593 * the task is unlocked, the timer is owned by the other task
594 * and may cease to exist at any time. Don't use or modify
595 * new_timer after the unlock call.
598 release_posix_timer(new_timer, it_id_set);
603 * Locking issues: We need to protect the result of the id look up until
604 * we get the timer locked down so it is not deleted under us. The
605 * removal is done under the idr spinlock so we use that here to bridge
606 * the find to the timer lock. To avoid a dead lock, the timer id MUST
607 * be release with out holding the timer lock.
609 static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
611 struct k_itimer *timr;
613 * Watch out here. We do a irqsave on the idr_lock and pass the
614 * flags part over to the timer lock. Must not let interrupts in
615 * while we are moving the lock.
617 spin_lock_irqsave(&idr_lock, *flags);
618 timr = idr_find(&posix_timers_id, (int)timer_id);
620 spin_lock(&timr->it_lock);
621 if (timr->it_signal == current->signal) {
622 spin_unlock(&idr_lock);
625 spin_unlock(&timr->it_lock);
627 spin_unlock_irqrestore(&idr_lock, *flags);
633 * Get the time remaining on a POSIX.1b interval timer. This function
634 * is ALWAYS called with spin_lock_irq on the timer, thus it must not
637 * We have a couple of messes to clean up here. First there is the case
638 * of a timer that has a requeue pending. These timers should appear to
639 * be in the timer list with an expiry as if we were to requeue them
642 * The second issue is the SIGEV_NONE timer which may be active but is
643 * not really ever put in the timer list (to save system resources).
644 * This timer may be expired, and if so, we will do it here. Otherwise
645 * it is the same as a requeue pending timer WRT to what we should
649 common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
651 ktime_t now, remaining, iv;
652 struct hrtimer *timer = &timr->it.real.timer;
654 memset(cur_setting, 0, sizeof(struct itimerspec));
656 iv = timr->it.real.interval;
658 /* interval timer ? */
660 cur_setting->it_interval = ktime_to_timespec(iv);
661 else if (!hrtimer_active(timer) &&
662 (timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
665 now = timer->base->get_time();
668 * When a requeue is pending or this is a SIGEV_NONE
669 * timer move the expiry time forward by intervals, so
672 if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
673 (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
674 timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
676 remaining = ktime_sub(hrtimer_get_expires(timer), now);
677 /* Return 0 only, when the timer is expired and not pending */
678 if (remaining.tv64 <= 0) {
680 * A single shot SIGEV_NONE timer must return 0, when
683 if ((timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
684 cur_setting->it_value.tv_nsec = 1;
686 cur_setting->it_value = ktime_to_timespec(remaining);
689 /* Get the time remaining on a POSIX.1b interval timer. */
690 SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
691 struct itimerspec __user *, setting)
693 struct itimerspec cur_setting;
694 struct k_itimer *timr;
699 timr = lock_timer(timer_id, &flags);
703 kc = clockid_to_kclock(timr->it_clock);
704 if (WARN_ON_ONCE(!kc || !kc->timer_get))
707 kc->timer_get(timr, &cur_setting);
709 unlock_timer(timr, flags);
711 if (!ret && copy_to_user(setting, &cur_setting, sizeof (cur_setting)))
718 * Get the number of overruns of a POSIX.1b interval timer. This is to
719 * be the overrun of the timer last delivered. At the same time we are
720 * accumulating overruns on the next timer. The overrun is frozen when
721 * the signal is delivered, either at the notify time (if the info block
722 * is not queued) or at the actual delivery time (as we are informed by
723 * the call back to do_schedule_next_timer(). So all we need to do is
724 * to pick up the frozen overrun.
726 SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
728 struct k_itimer *timr;
732 timr = lock_timer(timer_id, &flags);
736 overrun = timr->it_overrun_last;
737 unlock_timer(timr, flags);
742 /* Set a POSIX.1b interval timer. */
743 /* timr->it_lock is taken. */
745 common_timer_set(struct k_itimer *timr, int flags,
746 struct itimerspec *new_setting, struct itimerspec *old_setting)
748 struct hrtimer *timer = &timr->it.real.timer;
749 enum hrtimer_mode mode;
752 common_timer_get(timr, old_setting);
754 /* disable the timer */
755 timr->it.real.interval.tv64 = 0;
757 * careful here. If smp we could be in the "fire" routine which will
758 * be spinning as we hold the lock. But this is ONLY an SMP issue.
760 if (hrtimer_try_to_cancel(timer) < 0)
763 timr->it_requeue_pending = (timr->it_requeue_pending + 2) &
765 timr->it_overrun_last = 0;
767 /* switch off the timer when it_value is zero */
768 if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
771 mode = flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
772 hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
773 timr->it.real.timer.function = posix_timer_fn;
775 hrtimer_set_expires(timer, timespec_to_ktime(new_setting->it_value));
777 /* Convert interval */
778 timr->it.real.interval = timespec_to_ktime(new_setting->it_interval);
780 /* SIGEV_NONE timers are not queued ! See common_timer_get */
781 if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
782 /* Setup correct expiry time for relative timers */
783 if (mode == HRTIMER_MODE_REL) {
784 hrtimer_add_expires(timer, timer->base->get_time());
789 hrtimer_start_expires(timer, mode);
793 /* Set a POSIX.1b interval timer */
794 SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
795 const struct itimerspec __user *, new_setting,
796 struct itimerspec __user *, old_setting)
798 struct k_itimer *timr;
799 struct itimerspec new_spec, old_spec;
802 struct itimerspec *rtn = old_setting ? &old_spec : NULL;
808 if (copy_from_user(&new_spec, new_setting, sizeof (new_spec)))
811 if (!timespec_valid(&new_spec.it_interval) ||
812 !timespec_valid(&new_spec.it_value))
815 timr = lock_timer(timer_id, &flag);
819 kc = clockid_to_kclock(timr->it_clock);
820 if (WARN_ON_ONCE(!kc || !kc->timer_set))
823 error = kc->timer_set(timr, flags, &new_spec, rtn);
825 unlock_timer(timr, flag);
826 if (error == TIMER_RETRY) {
827 rtn = NULL; // We already got the old time...
831 if (old_setting && !error &&
832 copy_to_user(old_setting, &old_spec, sizeof (old_spec)))
838 static int common_timer_del(struct k_itimer *timer)
840 timer->it.real.interval.tv64 = 0;
842 if (hrtimer_try_to_cancel(&timer->it.real.timer) < 0)
847 static inline int timer_delete_hook(struct k_itimer *timer)
849 struct k_clock *kc = clockid_to_kclock(timer->it_clock);
851 if (WARN_ON_ONCE(!kc || !kc->timer_del))
853 return kc->timer_del(timer);
856 /* Delete a POSIX.1b interval timer. */
857 SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
859 struct k_itimer *timer;
863 timer = lock_timer(timer_id, &flags);
867 if (timer_delete_hook(timer) == TIMER_RETRY) {
868 unlock_timer(timer, flags);
872 spin_lock(¤t->sighand->siglock);
873 list_del(&timer->list);
874 spin_unlock(¤t->sighand->siglock);
876 * This keeps any tasks waiting on the spin lock from thinking
877 * they got something (see the lock code above).
879 timer->it_signal = NULL;
881 unlock_timer(timer, flags);
882 release_posix_timer(timer, IT_ID_SET);
887 * return timer owned by the process, used by exit_itimers
889 static void itimer_delete(struct k_itimer *timer)
894 spin_lock_irqsave(&timer->it_lock, flags);
896 if (timer_delete_hook(timer) == TIMER_RETRY) {
897 unlock_timer(timer, flags);
900 list_del(&timer->list);
902 * This keeps any tasks waiting on the spin lock from thinking
903 * they got something (see the lock code above).
905 timer->it_signal = NULL;
907 unlock_timer(timer, flags);
908 release_posix_timer(timer, IT_ID_SET);
912 * This is called by do_exit or de_thread, only when there are no more
913 * references to the shared signal_struct.
915 void exit_itimers(struct signal_struct *sig)
917 struct k_itimer *tmr;
919 while (!list_empty(&sig->posix_timers)) {
920 tmr = list_entry(sig->posix_timers.next, struct k_itimer, list);
925 SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
926 const struct timespec __user *, tp)
928 struct k_clock *kc = clockid_to_kclock(which_clock);
929 struct timespec new_tp;
931 if (!kc || !kc->clock_set)
934 if (copy_from_user(&new_tp, tp, sizeof (*tp)))
937 return kc->clock_set(which_clock, &new_tp);
940 SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
941 struct timespec __user *,tp)
943 struct k_clock *kc = clockid_to_kclock(which_clock);
944 struct timespec kernel_tp;
950 error = kc->clock_get(which_clock, &kernel_tp);
952 if (!error && copy_to_user(tp, &kernel_tp, sizeof (kernel_tp)))
958 SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
959 struct timex __user *, utx)
961 struct k_clock *kc = clockid_to_kclock(which_clock);
970 if (copy_from_user(&ktx, utx, sizeof(ktx)))
973 err = kc->clock_adj(which_clock, &ktx);
975 if (!err && copy_to_user(utx, &ktx, sizeof(ktx)))
981 SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
982 struct timespec __user *, tp)
984 struct k_clock *kc = clockid_to_kclock(which_clock);
985 struct timespec rtn_tp;
991 error = kc->clock_getres(which_clock, &rtn_tp);
993 if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp)))
1000 * nanosleep for monotonic and realtime clocks
1002 static int common_nsleep(const clockid_t which_clock, int flags,
1003 struct timespec *tsave, struct timespec __user *rmtp)
1005 return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
1006 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
1010 SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
1011 const struct timespec __user *, rqtp,
1012 struct timespec __user *, rmtp)
1014 struct k_clock *kc = clockid_to_kclock(which_clock);
1020 return -ENANOSLEEP_NOTSUP;
1022 if (copy_from_user(&t, rqtp, sizeof (struct timespec)))
1025 if (!timespec_valid(&t))
1028 return kc->nsleep(which_clock, flags, &t, rmtp);
1032 * This will restart clock_nanosleep. This is required only by
1033 * compat_clock_nanosleep_restart for now.
1035 long clock_nanosleep_restart(struct restart_block *restart_block)
1037 clockid_t which_clock = restart_block->nanosleep.index;
1038 struct k_clock *kc = clockid_to_kclock(which_clock);
1040 if (WARN_ON_ONCE(!kc || !kc->nsleep_restart))
1043 return kc->nsleep_restart(restart_block);