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Linux/kernel/time/posix-timers.c

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  1 /*
  2  * linux/kernel/posix-timers.c
  3  *
  4  *
  5  * 2002-10-15  Posix Clocks & timers
  6  *                           by George Anzinger george@mvista.com
  7  *
  8  *                           Copyright (C) 2002 2003 by MontaVista Software.
  9  *
 10  * 2004-06-01  Fix CLOCK_REALTIME clock/timer TIMER_ABSTIME bug.
 11  *                           Copyright (C) 2004 Boris Hu
 12  *
 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.
 17  *
 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.
 22 
 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.
 26  *
 27  * MontaVista Software | 1237 East Arques Avenue | Sunnyvale | CA 94085 | USA
 28  */
 29 
 30 /* These are all the functions necessary to implement
 31  * POSIX clocks & timers
 32  */
 33 #include <linux/mm.h>
 34 #include <linux/interrupt.h>
 35 #include <linux/slab.h>
 36 #include <linux/time.h>
 37 #include <linux/mutex.h>
 38 #include <linux/sched/task.h>
 39 
 40 #include <linux/uaccess.h>
 41 #include <linux/list.h>
 42 #include <linux/init.h>
 43 #include <linux/compiler.h>
 44 #include <linux/hash.h>
 45 #include <linux/posix-clock.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/export.h>
 51 #include <linux/hashtable.h>
 52 #include <linux/compat.h>
 53 #include <linux/nospec.h>
 54 
 55 #include "timekeeping.h"
 56 #include "posix-timers.h"
 57 
 58 /*
 59  * Management arrays for POSIX timers. Timers are now kept in static hash table
 60  * with 512 entries.
 61  * Timer ids are allocated by local routine, which selects proper hash head by
 62  * key, constructed from current->signal address and per signal struct counter.
 63  * This keeps timer ids unique per process, but now they can intersect between
 64  * processes.
 65  */
 66 
 67 /*
 68  * Lets keep our timers in a slab cache :-)
 69  */
 70 static struct kmem_cache *posix_timers_cache;
 71 
 72 static DEFINE_HASHTABLE(posix_timers_hashtable, 9);
 73 static DEFINE_SPINLOCK(hash_lock);
 74 
 75 static const struct k_clock * const posix_clocks[];
 76 static const struct k_clock *clockid_to_kclock(const clockid_t id);
 77 static const struct k_clock clock_realtime, clock_monotonic;
 78 
 79 /*
 80  * we assume that the new SIGEV_THREAD_ID shares no bits with the other
 81  * SIGEV values.  Here we put out an error if this assumption fails.
 82  */
 83 #if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
 84                        ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
 85 #error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
 86 #endif
 87 
 88 /*
 89  * parisc wants ENOTSUP instead of EOPNOTSUPP
 90  */
 91 #ifndef ENOTSUP
 92 # define ENANOSLEEP_NOTSUP EOPNOTSUPP
 93 #else
 94 # define ENANOSLEEP_NOTSUP ENOTSUP
 95 #endif
 96 
 97 /*
 98  * The timer ID is turned into a timer address by idr_find().
 99  * Verifying a valid ID consists of:
100  *
101  * a) checking that idr_find() returns other than -1.
102  * b) checking that the timer id matches the one in the timer itself.
103  * c) that the timer owner is in the callers thread group.
104  */
105 
106 /*
107  * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
108  *          to implement others.  This structure defines the various
109  *          clocks.
110  *
111  * RESOLUTION: Clock resolution is used to round up timer and interval
112  *          times, NOT to report clock times, which are reported with as
113  *          much resolution as the system can muster.  In some cases this
114  *          resolution may depend on the underlying clock hardware and
115  *          may not be quantifiable until run time, and only then is the
116  *          necessary code is written.  The standard says we should say
117  *          something about this issue in the documentation...
118  *
119  * FUNCTIONS: The CLOCKs structure defines possible functions to
120  *          handle various clock functions.
121  *
122  *          The standard POSIX timer management code assumes the
123  *          following: 1.) The k_itimer struct (sched.h) is used for
124  *          the timer.  2.) The list, it_lock, it_clock, it_id and
125  *          it_pid fields are not modified by timer code.
126  *
127  * Permissions: It is assumed that the clock_settime() function defined
128  *          for each clock will take care of permission checks.  Some
129  *          clocks may be set able by any user (i.e. local process
130  *          clocks) others not.  Currently the only set able clock we
131  *          have is CLOCK_REALTIME and its high res counter part, both of
132  *          which we beg off on and pass to do_sys_settimeofday().
133  */
134 static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
135 
136 #define lock_timer(tid, flags)                                             \
137 ({      struct k_itimer *__timr;                                           \
138         __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags));  \
139         __timr;                                                            \
140 })
141 
142 static int hash(struct signal_struct *sig, unsigned int nr)
143 {
144         return hash_32(hash32_ptr(sig) ^ nr, HASH_BITS(posix_timers_hashtable));
145 }
146 
147 static struct k_itimer *__posix_timers_find(struct hlist_head *head,
148                                             struct signal_struct *sig,
149                                             timer_t id)
150 {
151         struct k_itimer *timer;
152 
153         hlist_for_each_entry_rcu(timer, head, t_hash) {
154                 if ((timer->it_signal == sig) && (timer->it_id == id))
155                         return timer;
156         }
157         return NULL;
158 }
159 
160 static struct k_itimer *posix_timer_by_id(timer_t id)
161 {
162         struct signal_struct *sig = current->signal;
163         struct hlist_head *head = &posix_timers_hashtable[hash(sig, id)];
164 
165         return __posix_timers_find(head, sig, id);
166 }
167 
168 static int posix_timer_add(struct k_itimer *timer)
169 {
170         struct signal_struct *sig = current->signal;
171         int first_free_id = sig->posix_timer_id;
172         struct hlist_head *head;
173         int ret = -ENOENT;
174 
175         do {
176                 spin_lock(&hash_lock);
177                 head = &posix_timers_hashtable[hash(sig, sig->posix_timer_id)];
178                 if (!__posix_timers_find(head, sig, sig->posix_timer_id)) {
179                         hlist_add_head_rcu(&timer->t_hash, head);
180                         ret = sig->posix_timer_id;
181                 }
182                 if (++sig->posix_timer_id < 0)
183                         sig->posix_timer_id = 0;
184                 if ((sig->posix_timer_id == first_free_id) && (ret == -ENOENT))
185                         /* Loop over all possible ids completed */
186                         ret = -EAGAIN;
187                 spin_unlock(&hash_lock);
188         } while (ret == -ENOENT);
189         return ret;
190 }
191 
192 static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
193 {
194         spin_unlock_irqrestore(&timr->it_lock, flags);
195 }
196 
197 /* Get clock_realtime */
198 static int posix_clock_realtime_get(clockid_t which_clock, struct timespec64 *tp)
199 {
200         ktime_get_real_ts64(tp);
201         return 0;
202 }
203 
204 /* Set clock_realtime */
205 static int posix_clock_realtime_set(const clockid_t which_clock,
206                                     const struct timespec64 *tp)
207 {
208         return do_sys_settimeofday64(tp, NULL);
209 }
210 
211 static int posix_clock_realtime_adj(const clockid_t which_clock,
212                                     struct timex *t)
213 {
214         return do_adjtimex(t);
215 }
216 
217 /*
218  * Get monotonic time for posix timers
219  */
220 static int posix_ktime_get_ts(clockid_t which_clock, struct timespec64 *tp)
221 {
222         ktime_get_ts64(tp);
223         return 0;
224 }
225 
226 /*
227  * Get monotonic-raw time for posix timers
228  */
229 static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
230 {
231         getrawmonotonic64(tp);
232         return 0;
233 }
234 
235 
236 static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec64 *tp)
237 {
238         *tp = current_kernel_time64();
239         return 0;
240 }
241 
242 static int posix_get_monotonic_coarse(clockid_t which_clock,
243                                                 struct timespec64 *tp)
244 {
245         *tp = get_monotonic_coarse64();
246         return 0;
247 }
248 
249 static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *tp)
250 {
251         *tp = ktime_to_timespec64(KTIME_LOW_RES);
252         return 0;
253 }
254 
255 static int posix_get_boottime(const clockid_t which_clock, struct timespec64 *tp)
256 {
257         get_monotonic_boottime64(tp);
258         return 0;
259 }
260 
261 static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp)
262 {
263         timekeeping_clocktai64(tp);
264         return 0;
265 }
266 
267 static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp)
268 {
269         tp->tv_sec = 0;
270         tp->tv_nsec = hrtimer_resolution;
271         return 0;
272 }
273 
274 /*
275  * Initialize everything, well, just everything in Posix clocks/timers ;)
276  */
277 static __init int init_posix_timers(void)
278 {
279         posix_timers_cache = kmem_cache_create("posix_timers_cache",
280                                         sizeof (struct k_itimer), 0, SLAB_PANIC,
281                                         NULL);
282         return 0;
283 }
284 __initcall(init_posix_timers);
285 
286 static void common_hrtimer_rearm(struct k_itimer *timr)
287 {
288         struct hrtimer *timer = &timr->it.real.timer;
289 
290         if (!timr->it_interval)
291                 return;
292 
293         timr->it_overrun += (unsigned int) hrtimer_forward(timer,
294                                                 timer->base->get_time(),
295                                                 timr->it_interval);
296         hrtimer_restart(timer);
297 }
298 
299 /*
300  * This function is exported for use by the signal deliver code.  It is
301  * called just prior to the info block being released and passes that
302  * block to us.  It's function is to update the overrun entry AND to
303  * restart the timer.  It should only be called if the timer is to be
304  * restarted (i.e. we have flagged this in the sys_private entry of the
305  * info block).
306  *
307  * To protect against the timer going away while the interrupt is queued,
308  * we require that the it_requeue_pending flag be set.
309  */
310 void posixtimer_rearm(struct siginfo *info)
311 {
312         struct k_itimer *timr;
313         unsigned long flags;
314 
315         timr = lock_timer(info->si_tid, &flags);
316         if (!timr)
317                 return;
318 
319         if (timr->it_requeue_pending == info->si_sys_private) {
320                 timr->kclock->timer_rearm(timr);
321 
322                 timr->it_active = 1;
323                 timr->it_overrun_last = timr->it_overrun;
324                 timr->it_overrun = -1;
325                 ++timr->it_requeue_pending;
326 
327                 info->si_overrun += timr->it_overrun_last;
328         }
329 
330         unlock_timer(timr, flags);
331 }
332 
333 int posix_timer_event(struct k_itimer *timr, int si_private)
334 {
335         struct task_struct *task;
336         int shared, ret = -1;
337         /*
338          * FIXME: if ->sigq is queued we can race with
339          * dequeue_signal()->posixtimer_rearm().
340          *
341          * If dequeue_signal() sees the "right" value of
342          * si_sys_private it calls posixtimer_rearm().
343          * We re-queue ->sigq and drop ->it_lock().
344          * posixtimer_rearm() locks the timer
345          * and re-schedules it while ->sigq is pending.
346          * Not really bad, but not that we want.
347          */
348         timr->sigq->info.si_sys_private = si_private;
349 
350         rcu_read_lock();
351         task = pid_task(timr->it_pid, PIDTYPE_PID);
352         if (task) {
353                 shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID);
354                 ret = send_sigqueue(timr->sigq, task, shared);
355         }
356         rcu_read_unlock();
357         /* If we failed to send the signal the timer stops. */
358         return ret > 0;
359 }
360 
361 /*
362  * This function gets called when a POSIX.1b interval timer expires.  It
363  * is used as a callback from the kernel internal timer.  The
364  * run_timer_list code ALWAYS calls with interrupts on.
365 
366  * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
367  */
368 static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
369 {
370         struct k_itimer *timr;
371         unsigned long flags;
372         int si_private = 0;
373         enum hrtimer_restart ret = HRTIMER_NORESTART;
374 
375         timr = container_of(timer, struct k_itimer, it.real.timer);
376         spin_lock_irqsave(&timr->it_lock, flags);
377 
378         timr->it_active = 0;
379         if (timr->it_interval != 0)
380                 si_private = ++timr->it_requeue_pending;
381 
382         if (posix_timer_event(timr, si_private)) {
383                 /*
384                  * signal was not sent because of sig_ignor
385                  * we will not get a call back to restart it AND
386                  * it should be restarted.
387                  */
388                 if (timr->it_interval != 0) {
389                         ktime_t now = hrtimer_cb_get_time(timer);
390 
391                         /*
392                          * FIXME: What we really want, is to stop this
393                          * timer completely and restart it in case the
394                          * SIG_IGN is removed. This is a non trivial
395                          * change which involves sighand locking
396                          * (sigh !), which we don't want to do late in
397                          * the release cycle.
398                          *
399                          * For now we just let timers with an interval
400                          * less than a jiffie expire every jiffie to
401                          * avoid softirq starvation in case of SIG_IGN
402                          * and a very small interval, which would put
403                          * the timer right back on the softirq pending
404                          * list. By moving now ahead of time we trick
405                          * hrtimer_forward() to expire the timer
406                          * later, while we still maintain the overrun
407                          * accuracy, but have some inconsistency in
408                          * the timer_gettime() case. This is at least
409                          * better than a starved softirq. A more
410                          * complex fix which solves also another related
411                          * inconsistency is already in the pipeline.
412                          */
413 #ifdef CONFIG_HIGH_RES_TIMERS
414                         {
415                                 ktime_t kj = NSEC_PER_SEC / HZ;
416 
417                                 if (timr->it_interval < kj)
418                                         now = ktime_add(now, kj);
419                         }
420 #endif
421                         timr->it_overrun += (unsigned int)
422                                 hrtimer_forward(timer, now,
423                                                 timr->it_interval);
424                         ret = HRTIMER_RESTART;
425                         ++timr->it_requeue_pending;
426                         timr->it_active = 1;
427                 }
428         }
429 
430         unlock_timer(timr, flags);
431         return ret;
432 }
433 
434 static struct pid *good_sigevent(sigevent_t * event)
435 {
436         struct task_struct *rtn = current->group_leader;
437 
438         switch (event->sigev_notify) {
439         case SIGEV_SIGNAL | SIGEV_THREAD_ID:
440                 rtn = find_task_by_vpid(event->sigev_notify_thread_id);
441                 if (!rtn || !same_thread_group(rtn, current))
442                         return NULL;
443                 /* FALLTHRU */
444         case SIGEV_SIGNAL:
445         case SIGEV_THREAD:
446                 if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
447                         return NULL;
448                 /* FALLTHRU */
449         case SIGEV_NONE:
450                 return task_pid(rtn);
451         default:
452                 return NULL;
453         }
454 }
455 
456 static struct k_itimer * alloc_posix_timer(void)
457 {
458         struct k_itimer *tmr;
459         tmr = kmem_cache_zalloc(posix_timers_cache, GFP_KERNEL);
460         if (!tmr)
461                 return tmr;
462         if (unlikely(!(tmr->sigq = sigqueue_alloc()))) {
463                 kmem_cache_free(posix_timers_cache, tmr);
464                 return NULL;
465         }
466         memset(&tmr->sigq->info, 0, sizeof(siginfo_t));
467         return tmr;
468 }
469 
470 static void k_itimer_rcu_free(struct rcu_head *head)
471 {
472         struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu);
473 
474         kmem_cache_free(posix_timers_cache, tmr);
475 }
476 
477 #define IT_ID_SET       1
478 #define IT_ID_NOT_SET   0
479 static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
480 {
481         if (it_id_set) {
482                 unsigned long flags;
483                 spin_lock_irqsave(&hash_lock, flags);
484                 hlist_del_rcu(&tmr->t_hash);
485                 spin_unlock_irqrestore(&hash_lock, flags);
486         }
487         put_pid(tmr->it_pid);
488         sigqueue_free(tmr->sigq);
489         call_rcu(&tmr->it.rcu, k_itimer_rcu_free);
490 }
491 
492 static int common_timer_create(struct k_itimer *new_timer)
493 {
494         hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
495         return 0;
496 }
497 
498 /* Create a POSIX.1b interval timer. */
499 static int do_timer_create(clockid_t which_clock, struct sigevent *event,
500                            timer_t __user *created_timer_id)
501 {
502         const struct k_clock *kc = clockid_to_kclock(which_clock);
503         struct k_itimer *new_timer;
504         int error, new_timer_id;
505         int it_id_set = IT_ID_NOT_SET;
506 
507         if (!kc)
508                 return -EINVAL;
509         if (!kc->timer_create)
510                 return -EOPNOTSUPP;
511 
512         new_timer = alloc_posix_timer();
513         if (unlikely(!new_timer))
514                 return -EAGAIN;
515 
516         spin_lock_init(&new_timer->it_lock);
517         new_timer_id = posix_timer_add(new_timer);
518         if (new_timer_id < 0) {
519                 error = new_timer_id;
520                 goto out;
521         }
522 
523         it_id_set = IT_ID_SET;
524         new_timer->it_id = (timer_t) new_timer_id;
525         new_timer->it_clock = which_clock;
526         new_timer->kclock = kc;
527         new_timer->it_overrun = -1;
528 
529         if (event) {
530                 rcu_read_lock();
531                 new_timer->it_pid = get_pid(good_sigevent(event));
532                 rcu_read_unlock();
533                 if (!new_timer->it_pid) {
534                         error = -EINVAL;
535                         goto out;
536                 }
537                 new_timer->it_sigev_notify     = event->sigev_notify;
538                 new_timer->sigq->info.si_signo = event->sigev_signo;
539                 new_timer->sigq->info.si_value = event->sigev_value;
540         } else {
541                 new_timer->it_sigev_notify     = SIGEV_SIGNAL;
542                 new_timer->sigq->info.si_signo = SIGALRM;
543                 memset(&new_timer->sigq->info.si_value, 0, sizeof(sigval_t));
544                 new_timer->sigq->info.si_value.sival_int = new_timer->it_id;
545                 new_timer->it_pid = get_pid(task_tgid(current));
546         }
547 
548         new_timer->sigq->info.si_tid   = new_timer->it_id;
549         new_timer->sigq->info.si_code  = SI_TIMER;
550 
551         if (copy_to_user(created_timer_id,
552                          &new_timer_id, sizeof (new_timer_id))) {
553                 error = -EFAULT;
554                 goto out;
555         }
556 
557         error = kc->timer_create(new_timer);
558         if (error)
559                 goto out;
560 
561         spin_lock_irq(&current->sighand->siglock);
562         new_timer->it_signal = current->signal;
563         list_add(&new_timer->list, &current->signal->posix_timers);
564         spin_unlock_irq(&current->sighand->siglock);
565 
566         return 0;
567         /*
568          * In the case of the timer belonging to another task, after
569          * the task is unlocked, the timer is owned by the other task
570          * and may cease to exist at any time.  Don't use or modify
571          * new_timer after the unlock call.
572          */
573 out:
574         release_posix_timer(new_timer, it_id_set);
575         return error;
576 }
577 
578 SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
579                 struct sigevent __user *, timer_event_spec,
580                 timer_t __user *, created_timer_id)
581 {
582         if (timer_event_spec) {
583                 sigevent_t event;
584 
585                 if (copy_from_user(&event, timer_event_spec, sizeof (event)))
586                         return -EFAULT;
587                 return do_timer_create(which_clock, &event, created_timer_id);
588         }
589         return do_timer_create(which_clock, NULL, created_timer_id);
590 }
591 
592 #ifdef CONFIG_COMPAT
593 COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
594                        struct compat_sigevent __user *, timer_event_spec,
595                        timer_t __user *, created_timer_id)
596 {
597         if (timer_event_spec) {
598                 sigevent_t event;
599 
600                 if (get_compat_sigevent(&event, timer_event_spec))
601                         return -EFAULT;
602                 return do_timer_create(which_clock, &event, created_timer_id);
603         }
604         return do_timer_create(which_clock, NULL, created_timer_id);
605 }
606 #endif
607 
608 /*
609  * Locking issues: We need to protect the result of the id look up until
610  * we get the timer locked down so it is not deleted under us.  The
611  * removal is done under the idr spinlock so we use that here to bridge
612  * the find to the timer lock.  To avoid a dead lock, the timer id MUST
613  * be release with out holding the timer lock.
614  */
615 static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
616 {
617         struct k_itimer *timr;
618 
619         /*
620          * timer_t could be any type >= int and we want to make sure any
621          * @timer_id outside positive int range fails lookup.
622          */
623         if ((unsigned long long)timer_id > INT_MAX)
624                 return NULL;
625 
626         rcu_read_lock();
627         timr = posix_timer_by_id(timer_id);
628         if (timr) {
629                 spin_lock_irqsave(&timr->it_lock, *flags);
630                 if (timr->it_signal == current->signal) {
631                         rcu_read_unlock();
632                         return timr;
633                 }
634                 spin_unlock_irqrestore(&timr->it_lock, *flags);
635         }
636         rcu_read_unlock();
637 
638         return NULL;
639 }
640 
641 static ktime_t common_hrtimer_remaining(struct k_itimer *timr, ktime_t now)
642 {
643         struct hrtimer *timer = &timr->it.real.timer;
644 
645         return __hrtimer_expires_remaining_adjusted(timer, now);
646 }
647 
648 static int common_hrtimer_forward(struct k_itimer *timr, ktime_t now)
649 {
650         struct hrtimer *timer = &timr->it.real.timer;
651 
652         return (int)hrtimer_forward(timer, now, timr->it_interval);
653 }
654 
655 /*
656  * Get the time remaining on a POSIX.1b interval timer.  This function
657  * is ALWAYS called with spin_lock_irq on the timer, thus it must not
658  * mess with irq.
659  *
660  * We have a couple of messes to clean up here.  First there is the case
661  * of a timer that has a requeue pending.  These timers should appear to
662  * be in the timer list with an expiry as if we were to requeue them
663  * now.
664  *
665  * The second issue is the SIGEV_NONE timer which may be active but is
666  * not really ever put in the timer list (to save system resources).
667  * This timer may be expired, and if so, we will do it here.  Otherwise
668  * it is the same as a requeue pending timer WRT to what we should
669  * report.
670  */
671 void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
672 {
673         const struct k_clock *kc = timr->kclock;
674         ktime_t now, remaining, iv;
675         struct timespec64 ts64;
676         bool sig_none;
677 
678         sig_none = timr->it_sigev_notify == SIGEV_NONE;
679         iv = timr->it_interval;
680 
681         /* interval timer ? */
682         if (iv) {
683                 cur_setting->it_interval = ktime_to_timespec64(iv);
684         } else if (!timr->it_active) {
685                 /*
686                  * SIGEV_NONE oneshot timers are never queued. Check them
687                  * below.
688                  */
689                 if (!sig_none)
690                         return;
691         }
692 
693         /*
694          * The timespec64 based conversion is suboptimal, but it's not
695          * worth to implement yet another callback.
696          */
697         kc->clock_get(timr->it_clock, &ts64);
698         now = timespec64_to_ktime(ts64);
699 
700         /*
701          * When a requeue is pending or this is a SIGEV_NONE timer move the
702          * expiry time forward by intervals, so expiry is > now.
703          */
704         if (iv && (timr->it_requeue_pending & REQUEUE_PENDING || sig_none))
705                 timr->it_overrun += kc->timer_forward(timr, now);
706 
707         remaining = kc->timer_remaining(timr, now);
708         /* Return 0 only, when the timer is expired and not pending */
709         if (remaining <= 0) {
710                 /*
711                  * A single shot SIGEV_NONE timer must return 0, when
712                  * it is expired !
713                  */
714                 if (!sig_none)
715                         cur_setting->it_value.tv_nsec = 1;
716         } else {
717                 cur_setting->it_value = ktime_to_timespec64(remaining);
718         }
719 }
720 
721 /* Get the time remaining on a POSIX.1b interval timer. */
722 static int do_timer_gettime(timer_t timer_id,  struct itimerspec64 *setting)
723 {
724         struct k_itimer *timr;
725         const struct k_clock *kc;
726         unsigned long flags;
727         int ret = 0;
728 
729         timr = lock_timer(timer_id, &flags);
730         if (!timr)
731                 return -EINVAL;
732 
733         memset(setting, 0, sizeof(*setting));
734         kc = timr->kclock;
735         if (WARN_ON_ONCE(!kc || !kc->timer_get))
736                 ret = -EINVAL;
737         else
738                 kc->timer_get(timr, setting);
739 
740         unlock_timer(timr, flags);
741         return ret;
742 }
743 
744 /* Get the time remaining on a POSIX.1b interval timer. */
745 SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
746                 struct itimerspec __user *, setting)
747 {
748         struct itimerspec64 cur_setting;
749 
750         int ret = do_timer_gettime(timer_id, &cur_setting);
751         if (!ret) {
752                 if (put_itimerspec64(&cur_setting, setting))
753                         ret = -EFAULT;
754         }
755         return ret;
756 }
757 
758 #ifdef CONFIG_COMPAT
759 COMPAT_SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
760                        struct compat_itimerspec __user *, setting)
761 {
762         struct itimerspec64 cur_setting;
763 
764         int ret = do_timer_gettime(timer_id, &cur_setting);
765         if (!ret) {
766                 if (put_compat_itimerspec64(&cur_setting, setting))
767                         ret = -EFAULT;
768         }
769         return ret;
770 }
771 #endif
772 
773 /*
774  * Get the number of overruns of a POSIX.1b interval timer.  This is to
775  * be the overrun of the timer last delivered.  At the same time we are
776  * accumulating overruns on the next timer.  The overrun is frozen when
777  * the signal is delivered, either at the notify time (if the info block
778  * is not queued) or at the actual delivery time (as we are informed by
779  * the call back to posixtimer_rearm().  So all we need to do is
780  * to pick up the frozen overrun.
781  */
782 SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
783 {
784         struct k_itimer *timr;
785         int overrun;
786         unsigned long flags;
787 
788         timr = lock_timer(timer_id, &flags);
789         if (!timr)
790                 return -EINVAL;
791 
792         overrun = timr->it_overrun_last;
793         unlock_timer(timr, flags);
794 
795         return overrun;
796 }
797 
798 static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
799                                bool absolute, bool sigev_none)
800 {
801         struct hrtimer *timer = &timr->it.real.timer;
802         enum hrtimer_mode mode;
803 
804         mode = absolute ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
805         /*
806          * Posix magic: Relative CLOCK_REALTIME timers are not affected by
807          * clock modifications, so they become CLOCK_MONOTONIC based under the
808          * hood. See hrtimer_init(). Update timr->kclock, so the generic
809          * functions which use timr->kclock->clock_get() work.
810          *
811          * Note: it_clock stays unmodified, because the next timer_set() might
812          * use ABSTIME, so it needs to switch back.
813          */
814         if (timr->it_clock == CLOCK_REALTIME)
815                 timr->kclock = absolute ? &clock_realtime : &clock_monotonic;
816 
817         hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
818         timr->it.real.timer.function = posix_timer_fn;
819 
820         if (!absolute)
821                 expires = ktime_add_safe(expires, timer->base->get_time());
822         hrtimer_set_expires(timer, expires);
823 
824         if (!sigev_none)
825                 hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
826 }
827 
828 static int common_hrtimer_try_to_cancel(struct k_itimer *timr)
829 {
830         return hrtimer_try_to_cancel(&timr->it.real.timer);
831 }
832 
833 /* Set a POSIX.1b interval timer. */
834 int common_timer_set(struct k_itimer *timr, int flags,
835                      struct itimerspec64 *new_setting,
836                      struct itimerspec64 *old_setting)
837 {
838         const struct k_clock *kc = timr->kclock;
839         bool sigev_none;
840         ktime_t expires;
841 
842         if (old_setting)
843                 common_timer_get(timr, old_setting);
844 
845         /* Prevent rearming by clearing the interval */
846         timr->it_interval = 0;
847         /*
848          * Careful here. On SMP systems the timer expiry function could be
849          * active and spinning on timr->it_lock.
850          */
851         if (kc->timer_try_to_cancel(timr) < 0)
852                 return TIMER_RETRY;
853 
854         timr->it_active = 0;
855         timr->it_requeue_pending = (timr->it_requeue_pending + 2) &
856                 ~REQUEUE_PENDING;
857         timr->it_overrun_last = 0;
858 
859         /* Switch off the timer when it_value is zero */
860         if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
861                 return 0;
862 
863         timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
864         expires = timespec64_to_ktime(new_setting->it_value);
865         sigev_none = timr->it_sigev_notify == SIGEV_NONE;
866 
867         kc->timer_arm(timr, expires, flags & TIMER_ABSTIME, sigev_none);
868         timr->it_active = !sigev_none;
869         return 0;
870 }
871 
872 static int do_timer_settime(timer_t timer_id, int flags,
873                             struct itimerspec64 *new_spec64,
874                             struct itimerspec64 *old_spec64)
875 {
876         const struct k_clock *kc;
877         struct k_itimer *timr;
878         unsigned long flag;
879         int error = 0;
880 
881         if (!timespec64_valid(&new_spec64->it_interval) ||
882             !timespec64_valid(&new_spec64->it_value))
883                 return -EINVAL;
884 
885         if (old_spec64)
886                 memset(old_spec64, 0, sizeof(*old_spec64));
887 retry:
888         timr = lock_timer(timer_id, &flag);
889         if (!timr)
890                 return -EINVAL;
891 
892         kc = timr->kclock;
893         if (WARN_ON_ONCE(!kc || !kc->timer_set))
894                 error = -EINVAL;
895         else
896                 error = kc->timer_set(timr, flags, new_spec64, old_spec64);
897 
898         unlock_timer(timr, flag);
899         if (error == TIMER_RETRY) {
900                 old_spec64 = NULL;      // We already got the old time...
901                 goto retry;
902         }
903 
904         return error;
905 }
906 
907 /* Set a POSIX.1b interval timer */
908 SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
909                 const struct itimerspec __user *, new_setting,
910                 struct itimerspec __user *, old_setting)
911 {
912         struct itimerspec64 new_spec, old_spec;
913         struct itimerspec64 *rtn = old_setting ? &old_spec : NULL;
914         int error = 0;
915 
916         if (!new_setting)
917                 return -EINVAL;
918 
919         if (get_itimerspec64(&new_spec, new_setting))
920                 return -EFAULT;
921 
922         error = do_timer_settime(timer_id, flags, &new_spec, rtn);
923         if (!error && old_setting) {
924                 if (put_itimerspec64(&old_spec, old_setting))
925                         error = -EFAULT;
926         }
927         return error;
928 }
929 
930 #ifdef CONFIG_COMPAT
931 COMPAT_SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
932                        struct compat_itimerspec __user *, new,
933                        struct compat_itimerspec __user *, old)
934 {
935         struct itimerspec64 new_spec, old_spec;
936         struct itimerspec64 *rtn = old ? &old_spec : NULL;
937         int error = 0;
938 
939         if (!new)
940                 return -EINVAL;
941         if (get_compat_itimerspec64(&new_spec, new))
942                 return -EFAULT;
943 
944         error = do_timer_settime(timer_id, flags, &new_spec, rtn);
945         if (!error && old) {
946                 if (put_compat_itimerspec64(&old_spec, old))
947                         error = -EFAULT;
948         }
949         return error;
950 }
951 #endif
952 
953 int common_timer_del(struct k_itimer *timer)
954 {
955         const struct k_clock *kc = timer->kclock;
956 
957         timer->it_interval = 0;
958         if (kc->timer_try_to_cancel(timer) < 0)
959                 return TIMER_RETRY;
960         timer->it_active = 0;
961         return 0;
962 }
963 
964 static inline int timer_delete_hook(struct k_itimer *timer)
965 {
966         const struct k_clock *kc = timer->kclock;
967 
968         if (WARN_ON_ONCE(!kc || !kc->timer_del))
969                 return -EINVAL;
970         return kc->timer_del(timer);
971 }
972 
973 /* Delete a POSIX.1b interval timer. */
974 SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
975 {
976         struct k_itimer *timer;
977         unsigned long flags;
978 
979 retry_delete:
980         timer = lock_timer(timer_id, &flags);
981         if (!timer)
982                 return -EINVAL;
983 
984         if (timer_delete_hook(timer) == TIMER_RETRY) {
985                 unlock_timer(timer, flags);
986                 goto retry_delete;
987         }
988 
989         spin_lock(&current->sighand->siglock);
990         list_del(&timer->list);
991         spin_unlock(&current->sighand->siglock);
992         /*
993          * This keeps any tasks waiting on the spin lock from thinking
994          * they got something (see the lock code above).
995          */
996         timer->it_signal = NULL;
997 
998         unlock_timer(timer, flags);
999         release_posix_timer(timer, IT_ID_SET);
1000         return 0;
1001 }
1002 
1003 /*
1004  * return timer owned by the process, used by exit_itimers
1005  */
1006 static void itimer_delete(struct k_itimer *timer)
1007 {
1008         unsigned long flags;
1009 
1010 retry_delete:
1011         spin_lock_irqsave(&timer->it_lock, flags);
1012 
1013         if (timer_delete_hook(timer) == TIMER_RETRY) {
1014                 unlock_timer(timer, flags);
1015                 goto retry_delete;
1016         }
1017         list_del(&timer->list);
1018         /*
1019          * This keeps any tasks waiting on the spin lock from thinking
1020          * they got something (see the lock code above).
1021          */
1022         timer->it_signal = NULL;
1023 
1024         unlock_timer(timer, flags);
1025         release_posix_timer(timer, IT_ID_SET);
1026 }
1027 
1028 /*
1029  * This is called by do_exit or de_thread, only when there are no more
1030  * references to the shared signal_struct.
1031  */
1032 void exit_itimers(struct signal_struct *sig)
1033 {
1034         struct k_itimer *tmr;
1035 
1036         while (!list_empty(&sig->posix_timers)) {
1037                 tmr = list_entry(sig->posix_timers.next, struct k_itimer, list);
1038                 itimer_delete(tmr);
1039         }
1040 }
1041 
1042 SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
1043                 const struct timespec __user *, tp)
1044 {
1045         const struct k_clock *kc = clockid_to_kclock(which_clock);
1046         struct timespec64 new_tp;
1047 
1048         if (!kc || !kc->clock_set)
1049                 return -EINVAL;
1050 
1051         if (get_timespec64(&new_tp, tp))
1052                 return -EFAULT;
1053 
1054         return kc->clock_set(which_clock, &new_tp);
1055 }
1056 
1057 SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
1058                 struct timespec __user *,tp)
1059 {
1060         const struct k_clock *kc = clockid_to_kclock(which_clock);
1061         struct timespec64 kernel_tp;
1062         int error;
1063 
1064         if (!kc)
1065                 return -EINVAL;
1066 
1067         error = kc->clock_get(which_clock, &kernel_tp);
1068 
1069         if (!error && put_timespec64(&kernel_tp, tp))
1070                 error = -EFAULT;
1071 
1072         return error;
1073 }
1074 
1075 SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
1076                 struct timex __user *, utx)
1077 {
1078         const struct k_clock *kc = clockid_to_kclock(which_clock);
1079         struct timex ktx;
1080         int err;
1081 
1082         if (!kc)
1083                 return -EINVAL;
1084         if (!kc->clock_adj)
1085                 return -EOPNOTSUPP;
1086 
1087         if (copy_from_user(&ktx, utx, sizeof(ktx)))
1088                 return -EFAULT;
1089 
1090         err = kc->clock_adj(which_clock, &ktx);
1091 
1092         if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
1093                 return -EFAULT;
1094 
1095         return err;
1096 }
1097 
1098 SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
1099                 struct timespec __user *, tp)
1100 {
1101         const struct k_clock *kc = clockid_to_kclock(which_clock);
1102         struct timespec64 rtn_tp;
1103         int error;
1104 
1105         if (!kc)
1106                 return -EINVAL;
1107 
1108         error = kc->clock_getres(which_clock, &rtn_tp);
1109 
1110         if (!error && tp && put_timespec64(&rtn_tp, tp))
1111                 error = -EFAULT;
1112 
1113         return error;
1114 }
1115 
1116 #ifdef CONFIG_COMPAT
1117 
1118 COMPAT_SYSCALL_DEFINE2(clock_settime, clockid_t, which_clock,
1119                        struct compat_timespec __user *, tp)
1120 {
1121         const struct k_clock *kc = clockid_to_kclock(which_clock);
1122         struct timespec64 ts;
1123 
1124         if (!kc || !kc->clock_set)
1125                 return -EINVAL;
1126 
1127         if (compat_get_timespec64(&ts, tp))
1128                 return -EFAULT;
1129 
1130         return kc->clock_set(which_clock, &ts);
1131 }
1132 
1133 COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
1134                        struct compat_timespec __user *, tp)
1135 {
1136         const struct k_clock *kc = clockid_to_kclock(which_clock);
1137         struct timespec64 ts;
1138         int err;
1139 
1140         if (!kc)
1141                 return -EINVAL;
1142 
1143         err = kc->clock_get(which_clock, &ts);
1144 
1145         if (!err && compat_put_timespec64(&ts, tp))
1146                 err = -EFAULT;
1147 
1148         return err;
1149 }
1150 
1151 COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,
1152                        struct compat_timex __user *, utp)
1153 {
1154         const struct k_clock *kc = clockid_to_kclock(which_clock);
1155         struct timex ktx;
1156         int err;
1157 
1158         if (!kc)
1159                 return -EINVAL;
1160         if (!kc->clock_adj)
1161                 return -EOPNOTSUPP;
1162 
1163         err = compat_get_timex(&ktx, utp);
1164         if (err)
1165                 return err;
1166 
1167         err = kc->clock_adj(which_clock, &ktx);
1168 
1169         if (err >= 0)
1170                 err = compat_put_timex(utp, &ktx);
1171 
1172         return err;
1173 }
1174 
1175 COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
1176                        struct compat_timespec __user *, tp)
1177 {
1178         const struct k_clock *kc = clockid_to_kclock(which_clock);
1179         struct timespec64 ts;
1180         int err;
1181 
1182         if (!kc)
1183                 return -EINVAL;
1184 
1185         err = kc->clock_getres(which_clock, &ts);
1186         if (!err && tp && compat_put_timespec64(&ts, tp))
1187                 return -EFAULT;
1188 
1189         return err;
1190 }
1191 
1192 #endif
1193 
1194 /*
1195  * nanosleep for monotonic and realtime clocks
1196  */
1197 static int common_nsleep(const clockid_t which_clock, int flags,
1198                          const struct timespec64 *rqtp)
1199 {
1200         return hrtimer_nanosleep(rqtp, flags & TIMER_ABSTIME ?
1201                                  HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
1202                                  which_clock);
1203 }
1204 
1205 SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
1206                 const struct timespec __user *, rqtp,
1207                 struct timespec __user *, rmtp)
1208 {
1209         const struct k_clock *kc = clockid_to_kclock(which_clock);
1210         struct timespec64 t;
1211 
1212         if (!kc)
1213                 return -EINVAL;
1214         if (!kc->nsleep)
1215                 return -ENANOSLEEP_NOTSUP;
1216 
1217         if (get_timespec64(&t, rqtp))
1218                 return -EFAULT;
1219 
1220         if (!timespec64_valid(&t))
1221                 return -EINVAL;
1222         if (flags & TIMER_ABSTIME)
1223                 rmtp = NULL;
1224         current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
1225         current->restart_block.nanosleep.rmtp = rmtp;
1226 
1227         return kc->nsleep(which_clock, flags, &t);
1228 }
1229 
1230 #ifdef CONFIG_COMPAT
1231 COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
1232                        struct compat_timespec __user *, rqtp,
1233                        struct compat_timespec __user *, rmtp)
1234 {
1235         const struct k_clock *kc = clockid_to_kclock(which_clock);
1236         struct timespec64 t;
1237 
1238         if (!kc)
1239                 return -EINVAL;
1240         if (!kc->nsleep)
1241                 return -ENANOSLEEP_NOTSUP;
1242 
1243         if (compat_get_timespec64(&t, rqtp))
1244                 return -EFAULT;
1245 
1246         if (!timespec64_valid(&t))
1247                 return -EINVAL;
1248         if (flags & TIMER_ABSTIME)
1249                 rmtp = NULL;
1250         current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
1251         current->restart_block.nanosleep.compat_rmtp = rmtp;
1252 
1253         return kc->nsleep(which_clock, flags, &t);
1254 }
1255 #endif
1256 
1257 static const struct k_clock clock_realtime = {
1258         .clock_getres           = posix_get_hrtimer_res,
1259         .clock_get              = posix_clock_realtime_get,
1260         .clock_set              = posix_clock_realtime_set,
1261         .clock_adj              = posix_clock_realtime_adj,
1262         .nsleep                 = common_nsleep,
1263         .timer_create           = common_timer_create,
1264         .timer_set              = common_timer_set,
1265         .timer_get              = common_timer_get,
1266         .timer_del              = common_timer_del,
1267         .timer_rearm            = common_hrtimer_rearm,
1268         .timer_forward          = common_hrtimer_forward,
1269         .timer_remaining        = common_hrtimer_remaining,
1270         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1271         .timer_arm              = common_hrtimer_arm,
1272 };
1273 
1274 static const struct k_clock clock_monotonic = {
1275         .clock_getres           = posix_get_hrtimer_res,
1276         .clock_get              = posix_ktime_get_ts,
1277         .nsleep                 = common_nsleep,
1278         .timer_create           = common_timer_create,
1279         .timer_set              = common_timer_set,
1280         .timer_get              = common_timer_get,
1281         .timer_del              = common_timer_del,
1282         .timer_rearm            = common_hrtimer_rearm,
1283         .timer_forward          = common_hrtimer_forward,
1284         .timer_remaining        = common_hrtimer_remaining,
1285         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1286         .timer_arm              = common_hrtimer_arm,
1287 };
1288 
1289 static const struct k_clock clock_monotonic_raw = {
1290         .clock_getres           = posix_get_hrtimer_res,
1291         .clock_get              = posix_get_monotonic_raw,
1292 };
1293 
1294 static const struct k_clock clock_realtime_coarse = {
1295         .clock_getres           = posix_get_coarse_res,
1296         .clock_get              = posix_get_realtime_coarse,
1297 };
1298 
1299 static const struct k_clock clock_monotonic_coarse = {
1300         .clock_getres           = posix_get_coarse_res,
1301         .clock_get              = posix_get_monotonic_coarse,
1302 };
1303 
1304 static const struct k_clock clock_tai = {
1305         .clock_getres           = posix_get_hrtimer_res,
1306         .clock_get              = posix_get_tai,
1307         .nsleep                 = common_nsleep,
1308         .timer_create           = common_timer_create,
1309         .timer_set              = common_timer_set,
1310         .timer_get              = common_timer_get,
1311         .timer_del              = common_timer_del,
1312         .timer_rearm            = common_hrtimer_rearm,
1313         .timer_forward          = common_hrtimer_forward,
1314         .timer_remaining        = common_hrtimer_remaining,
1315         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1316         .timer_arm              = common_hrtimer_arm,
1317 };
1318 
1319 static const struct k_clock clock_boottime = {
1320         .clock_getres           = posix_get_hrtimer_res,
1321         .clock_get              = posix_get_boottime,
1322         .nsleep                 = common_nsleep,
1323         .timer_create           = common_timer_create,
1324         .timer_set              = common_timer_set,
1325         .timer_get              = common_timer_get,
1326         .timer_del              = common_timer_del,
1327         .timer_rearm            = common_hrtimer_rearm,
1328         .timer_forward          = common_hrtimer_forward,
1329         .timer_remaining        = common_hrtimer_remaining,
1330         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1331         .timer_arm              = common_hrtimer_arm,
1332 };
1333 
1334 static const struct k_clock * const posix_clocks[] = {
1335         [CLOCK_REALTIME]                = &clock_realtime,
1336         [CLOCK_MONOTONIC]               = &clock_monotonic,
1337         [CLOCK_PROCESS_CPUTIME_ID]      = &clock_process,
1338         [CLOCK_THREAD_CPUTIME_ID]       = &clock_thread,
1339         [CLOCK_MONOTONIC_RAW]           = &clock_monotonic_raw,
1340         [CLOCK_REALTIME_COARSE]         = &clock_realtime_coarse,
1341         [CLOCK_MONOTONIC_COARSE]        = &clock_monotonic_coarse,
1342         [CLOCK_BOOTTIME]                = &clock_boottime,
1343         [CLOCK_REALTIME_ALARM]          = &alarm_clock,
1344         [CLOCK_BOOTTIME_ALARM]          = &alarm_clock,
1345         [CLOCK_TAI]                     = &clock_tai,
1346 };
1347 
1348 static const struct k_clock *clockid_to_kclock(const clockid_t id)
1349 {
1350         clockid_t idx = id;
1351 
1352         if (id < 0) {
1353                 return (id & CLOCKFD_MASK) == CLOCKFD ?
1354                         &clock_posix_dynamic : &clock_posix_cpu;
1355         }
1356 
1357         if (id >= ARRAY_SIZE(posix_clocks))
1358                 return NULL;
1359 
1360         return posix_clocks[array_index_nospec(idx, ARRAY_SIZE(posix_clocks))];
1361 }
1362 

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