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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * 2002-10-15 Posix Clocks & timers
4 * by George Anzinger george@mvista.com
5 * Copyright (C) 2002 2003 by MontaVista Software.
6 *
7 * 2004-06-01 Fix CLOCK_REALTIME clock/timer TIMER_ABSTIME bug.
8 * Copyright (C) 2004 Boris Hu
9 *
10 * These are all the functions necessary to implement POSIX clocks & timers
11 */
12#include <linux/mm.h>
13#include <linux/interrupt.h>
14#include <linux/slab.h>
15#include <linux/time.h>
16#include <linux/mutex.h>
17#include <linux/sched/task.h>
18
19#include <linux/uaccess.h>
20#include <linux/list.h>
21#include <linux/init.h>
22#include <linux/compiler.h>
23#include <linux/hash.h>
24#include <linux/posix-clock.h>
25#include <linux/posix-timers.h>
26#include <linux/syscalls.h>
27#include <linux/wait.h>
28#include <linux/workqueue.h>
29#include <linux/export.h>
30#include <linux/hashtable.h>
31#include <linux/compat.h>
32#include <linux/nospec.h>
33#include <linux/time_namespace.h>
34
35#include "timekeeping.h"
36#include "posix-timers.h"
37
38static struct kmem_cache *posix_timers_cache;
39
40/*
41 * Timers are managed in a hash table for lockless lookup. The hash key is
42 * constructed from current::signal and the timer ID and the timer is
43 * matched against current::signal and the timer ID when walking the hash
44 * bucket list.
45 *
46 * This allows checkpoint/restore to reconstruct the exact timer IDs for
47 * a process.
48 */
49static DEFINE_HASHTABLE(posix_timers_hashtable, 9);
50static DEFINE_SPINLOCK(hash_lock);
51
52static const struct k_clock * const posix_clocks[];
53static const struct k_clock *clockid_to_kclock(const clockid_t id);
54static const struct k_clock clock_realtime, clock_monotonic;
55
56/* SIGEV_THREAD_ID cannot share a bit with the other SIGEV values. */
57#if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
58 ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
59#error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
60#endif
61
62static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
63
64#define lock_timer(tid, flags) \
65({ struct k_itimer *__timr; \
66 __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags)); \
67 __timr; \
68})
69
70static int hash(struct signal_struct *sig, unsigned int nr)
71{
72 return hash_32(hash32_ptr(sig) ^ nr, HASH_BITS(posix_timers_hashtable));
73}
74
75static struct k_itimer *__posix_timers_find(struct hlist_head *head,
76 struct signal_struct *sig,
77 timer_t id)
78{
79 struct k_itimer *timer;
80
81 hlist_for_each_entry_rcu(timer, head, t_hash, lockdep_is_held(&hash_lock)) {
82 /* timer->it_signal can be set concurrently */
83 if ((READ_ONCE(timer->it_signal) == sig) && (timer->it_id == id))
84 return timer;
85 }
86 return NULL;
87}
88
89static struct k_itimer *posix_timer_by_id(timer_t id)
90{
91 struct signal_struct *sig = current->signal;
92 struct hlist_head *head = &posix_timers_hashtable[hash(sig, id)];
93
94 return __posix_timers_find(head, sig, id);
95}
96
97static int posix_timer_add(struct k_itimer *timer)
98{
99 struct signal_struct *sig = current->signal;
100 struct hlist_head *head;
101 unsigned int cnt, id;
102
103 /*
104 * FIXME: Replace this by a per signal struct xarray once there is
105 * a plan to handle the resulting CRIU regression gracefully.
106 */
107 for (cnt = 0; cnt <= INT_MAX; cnt++) {
108 spin_lock(&hash_lock);
109 id = sig->next_posix_timer_id;
110
111 /* Write the next ID back. Clamp it to the positive space */
112 sig->next_posix_timer_id = (id + 1) & INT_MAX;
113
114 head = &posix_timers_hashtable[hash(sig, id)];
115 if (!__posix_timers_find(head, sig, id)) {
116 hlist_add_head_rcu(&timer->t_hash, head);
117 spin_unlock(&hash_lock);
118 return id;
119 }
120 spin_unlock(&hash_lock);
121 }
122 /* POSIX return code when no timer ID could be allocated */
123 return -EAGAIN;
124}
125
126static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
127{
128 spin_unlock_irqrestore(&timr->it_lock, flags);
129}
130
131static int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 *tp)
132{
133 ktime_get_real_ts64(tp);
134 return 0;
135}
136
137static ktime_t posix_get_realtime_ktime(clockid_t which_clock)
138{
139 return ktime_get_real();
140}
141
142static int posix_clock_realtime_set(const clockid_t which_clock,
143 const struct timespec64 *tp)
144{
145 return do_sys_settimeofday64(tp, NULL);
146}
147
148static int posix_clock_realtime_adj(const clockid_t which_clock,
149 struct __kernel_timex *t)
150{
151 return do_adjtimex(t);
152}
153
154static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64 *tp)
155{
156 ktime_get_ts64(tp);
157 timens_add_monotonic(tp);
158 return 0;
159}
160
161static ktime_t posix_get_monotonic_ktime(clockid_t which_clock)
162{
163 return ktime_get();
164}
165
166static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
167{
168 ktime_get_raw_ts64(tp);
169 timens_add_monotonic(tp);
170 return 0;
171}
172
173static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec64 *tp)
174{
175 ktime_get_coarse_real_ts64(tp);
176 return 0;
177}
178
179static int posix_get_monotonic_coarse(clockid_t which_clock,
180 struct timespec64 *tp)
181{
182 ktime_get_coarse_ts64(tp);
183 timens_add_monotonic(tp);
184 return 0;
185}
186
187static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *tp)
188{
189 *tp = ktime_to_timespec64(KTIME_LOW_RES);
190 return 0;
191}
192
193static int posix_get_boottime_timespec(const clockid_t which_clock, struct timespec64 *tp)
194{
195 ktime_get_boottime_ts64(tp);
196 timens_add_boottime(tp);
197 return 0;
198}
199
200static ktime_t posix_get_boottime_ktime(const clockid_t which_clock)
201{
202 return ktime_get_boottime();
203}
204
205static int posix_get_tai_timespec(clockid_t which_clock, struct timespec64 *tp)
206{
207 ktime_get_clocktai_ts64(tp);
208 return 0;
209}
210
211static ktime_t posix_get_tai_ktime(clockid_t which_clock)
212{
213 return ktime_get_clocktai();
214}
215
216static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp)
217{
218 tp->tv_sec = 0;
219 tp->tv_nsec = hrtimer_resolution;
220 return 0;
221}
222
223static __init int init_posix_timers(void)
224{
225 posix_timers_cache = kmem_cache_create("posix_timers_cache",
226 sizeof(struct k_itimer), 0,
227 SLAB_PANIC | SLAB_ACCOUNT, NULL);
228 return 0;
229}
230__initcall(init_posix_timers);
231
232/*
233 * The siginfo si_overrun field and the return value of timer_getoverrun(2)
234 * are of type int. Clamp the overrun value to INT_MAX
235 */
236static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
237{
238 s64 sum = timr->it_overrun_last + (s64)baseval;
239
240 return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
241}
242
243static void common_hrtimer_rearm(struct k_itimer *timr)
244{
245 struct hrtimer *timer = &timr->it.real.timer;
246
247 timr->it_overrun += hrtimer_forward(timer, timer->base->get_time(),
248 timr->it_interval);
249 hrtimer_restart(timer);
250}
251
252/*
253 * This function is called from the signal delivery code if
254 * info->si_sys_private is not zero, which indicates that the timer has to
255 * be rearmed. Restart the timer and update info::si_overrun.
256 */
257void posixtimer_rearm(struct kernel_siginfo *info)
258{
259 struct k_itimer *timr;
260 unsigned long flags;
261
262 timr = lock_timer(info->si_tid, &flags);
263 if (!timr)
264 return;
265
266 if (timr->it_interval && timr->it_requeue_pending == info->si_sys_private) {
267 timr->kclock->timer_rearm(timr);
268
269 timr->it_active = 1;
270 timr->it_overrun_last = timr->it_overrun;
271 timr->it_overrun = -1LL;
272 ++timr->it_requeue_pending;
273
274 info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
275 }
276
277 unlock_timer(timr, flags);
278}
279
280int posix_timer_event(struct k_itimer *timr, int si_private)
281{
282 enum pid_type type;
283 int ret;
284 /*
285 * FIXME: if ->sigq is queued we can race with
286 * dequeue_signal()->posixtimer_rearm().
287 *
288 * If dequeue_signal() sees the "right" value of
289 * si_sys_private it calls posixtimer_rearm().
290 * We re-queue ->sigq and drop ->it_lock().
291 * posixtimer_rearm() locks the timer
292 * and re-schedules it while ->sigq is pending.
293 * Not really bad, but not that we want.
294 */
295 timr->sigq->info.si_sys_private = si_private;
296
297 type = !(timr->it_sigev_notify & SIGEV_THREAD_ID) ? PIDTYPE_TGID : PIDTYPE_PID;
298 ret = send_sigqueue(timr->sigq, timr->it_pid, type);
299 /* If we failed to send the signal the timer stops. */
300 return ret > 0;
301}
302
303/*
304 * This function gets called when a POSIX.1b interval timer expires from
305 * the HRTIMER interrupt (soft interrupt on RT kernels).
306 *
307 * Handles CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_BOOTTIME and CLOCK_TAI
308 * based timers.
309 */
310static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
311{
312 enum hrtimer_restart ret = HRTIMER_NORESTART;
313 struct k_itimer *timr;
314 unsigned long flags;
315 int si_private = 0;
316
317 timr = container_of(timer, struct k_itimer, it.real.timer);
318 spin_lock_irqsave(&timr->it_lock, flags);
319
320 timr->it_active = 0;
321 if (timr->it_interval != 0)
322 si_private = ++timr->it_requeue_pending;
323
324 if (posix_timer_event(timr, si_private)) {
325 /*
326 * The signal was not queued due to SIG_IGN. As a
327 * consequence the timer is not going to be rearmed from
328 * the signal delivery path. But as a real signal handler
329 * can be installed later the timer must be rearmed here.
330 */
331 if (timr->it_interval != 0) {
332 ktime_t now = hrtimer_cb_get_time(timer);
333
334 /*
335 * FIXME: What we really want, is to stop this
336 * timer completely and restart it in case the
337 * SIG_IGN is removed. This is a non trivial
338 * change to the signal handling code.
339 *
340 * For now let timers with an interval less than a
341 * jiffie expire every jiffie and recheck for a
342 * valid signal handler.
343 *
344 * This avoids interrupt starvation in case of a
345 * very small interval, which would expire the
346 * timer immediately again.
347 *
348 * Moving now ahead of time by one jiffie tricks
349 * hrtimer_forward() to expire the timer later,
350 * while it still maintains the overrun accuracy
351 * for the price of a slight inconsistency in the
352 * timer_gettime() case. This is at least better
353 * than a timer storm.
354 *
355 * Only required when high resolution timers are
356 * enabled as the periodic tick based timers are
357 * automatically aligned to the next tick.
358 */
359 if (IS_ENABLED(CONFIG_HIGH_RES_TIMERS)) {
360 ktime_t kj = TICK_NSEC;
361
362 if (timr->it_interval < kj)
363 now = ktime_add(now, kj);
364 }
365
366 timr->it_overrun += hrtimer_forward(timer, now, timr->it_interval);
367 ret = HRTIMER_RESTART;
368 ++timr->it_requeue_pending;
369 timr->it_active = 1;
370 }
371 }
372
373 unlock_timer(timr, flags);
374 return ret;
375}
376
377static struct pid *good_sigevent(sigevent_t * event)
378{
379 struct pid *pid = task_tgid(current);
380 struct task_struct *rtn;
381
382 switch (event->sigev_notify) {
383 case SIGEV_SIGNAL | SIGEV_THREAD_ID:
384 pid = find_vpid(event->sigev_notify_thread_id);
385 rtn = pid_task(pid, PIDTYPE_PID);
386 if (!rtn || !same_thread_group(rtn, current))
387 return NULL;
388 fallthrough;
389 case SIGEV_SIGNAL:
390 case SIGEV_THREAD:
391 if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
392 return NULL;
393 fallthrough;
394 case SIGEV_NONE:
395 return pid;
396 default:
397 return NULL;
398 }
399}
400
401static struct k_itimer * alloc_posix_timer(void)
402{
403 struct k_itimer *tmr = kmem_cache_zalloc(posix_timers_cache, GFP_KERNEL);
404
405 if (!tmr)
406 return tmr;
407 if (unlikely(!(tmr->sigq = sigqueue_alloc()))) {
408 kmem_cache_free(posix_timers_cache, tmr);
409 return NULL;
410 }
411 clear_siginfo(&tmr->sigq->info);
412 return tmr;
413}
414
415static void k_itimer_rcu_free(struct rcu_head *head)
416{
417 struct k_itimer *tmr = container_of(head, struct k_itimer, rcu);
418
419 kmem_cache_free(posix_timers_cache, tmr);
420}
421
422static void posix_timer_free(struct k_itimer *tmr)
423{
424 put_pid(tmr->it_pid);
425 sigqueue_free(tmr->sigq);
426 call_rcu(&tmr->rcu, k_itimer_rcu_free);
427}
428
429static void posix_timer_unhash_and_free(struct k_itimer *tmr)
430{
431 spin_lock(&hash_lock);
432 hlist_del_rcu(&tmr->t_hash);
433 spin_unlock(&hash_lock);
434 posix_timer_free(tmr);
435}
436
437static int common_timer_create(struct k_itimer *new_timer)
438{
439 hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
440 return 0;
441}
442
443/* Create a POSIX.1b interval timer. */
444static int do_timer_create(clockid_t which_clock, struct sigevent *event,
445 timer_t __user *created_timer_id)
446{
447 const struct k_clock *kc = clockid_to_kclock(which_clock);
448 struct k_itimer *new_timer;
449 int error, new_timer_id;
450
451 if (!kc)
452 return -EINVAL;
453 if (!kc->timer_create)
454 return -EOPNOTSUPP;
455
456 new_timer = alloc_posix_timer();
457 if (unlikely(!new_timer))
458 return -EAGAIN;
459
460 spin_lock_init(&new_timer->it_lock);
461
462 /*
463 * Add the timer to the hash table. The timer is not yet valid
464 * because new_timer::it_signal is still NULL. The timer id is also
465 * not yet visible to user space.
466 */
467 new_timer_id = posix_timer_add(new_timer);
468 if (new_timer_id < 0) {
469 posix_timer_free(new_timer);
470 return new_timer_id;
471 }
472
473 new_timer->it_id = (timer_t) new_timer_id;
474 new_timer->it_clock = which_clock;
475 new_timer->kclock = kc;
476 new_timer->it_overrun = -1LL;
477
478 if (event) {
479 rcu_read_lock();
480 new_timer->it_pid = get_pid(good_sigevent(event));
481 rcu_read_unlock();
482 if (!new_timer->it_pid) {
483 error = -EINVAL;
484 goto out;
485 }
486 new_timer->it_sigev_notify = event->sigev_notify;
487 new_timer->sigq->info.si_signo = event->sigev_signo;
488 new_timer->sigq->info.si_value = event->sigev_value;
489 } else {
490 new_timer->it_sigev_notify = SIGEV_SIGNAL;
491 new_timer->sigq->info.si_signo = SIGALRM;
492 memset(&new_timer->sigq->info.si_value, 0, sizeof(sigval_t));
493 new_timer->sigq->info.si_value.sival_int = new_timer->it_id;
494 new_timer->it_pid = get_pid(task_tgid(current));
495 }
496
497 new_timer->sigq->info.si_tid = new_timer->it_id;
498 new_timer->sigq->info.si_code = SI_TIMER;
499
500 if (copy_to_user(created_timer_id, &new_timer_id, sizeof (new_timer_id))) {
501 error = -EFAULT;
502 goto out;
503 }
504 /*
505 * After succesful copy out, the timer ID is visible to user space
506 * now but not yet valid because new_timer::signal is still NULL.
507 *
508 * Complete the initialization with the clock specific create
509 * callback.
510 */
511 error = kc->timer_create(new_timer);
512 if (error)
513 goto out;
514
515 spin_lock_irq(¤t->sighand->siglock);
516 /* This makes the timer valid in the hash table */
517 WRITE_ONCE(new_timer->it_signal, current->signal);
518 list_add(&new_timer->list, ¤t->signal->posix_timers);
519 spin_unlock_irq(¤t->sighand->siglock);
520 /*
521 * After unlocking sighand::siglock @new_timer is subject to
522 * concurrent removal and cannot be touched anymore
523 */
524 return 0;
525out:
526 posix_timer_unhash_and_free(new_timer);
527 return error;
528}
529
530SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
531 struct sigevent __user *, timer_event_spec,
532 timer_t __user *, created_timer_id)
533{
534 if (timer_event_spec) {
535 sigevent_t event;
536
537 if (copy_from_user(&event, timer_event_spec, sizeof (event)))
538 return -EFAULT;
539 return do_timer_create(which_clock, &event, created_timer_id);
540 }
541 return do_timer_create(which_clock, NULL, created_timer_id);
542}
543
544#ifdef CONFIG_COMPAT
545COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
546 struct compat_sigevent __user *, timer_event_spec,
547 timer_t __user *, created_timer_id)
548{
549 if (timer_event_spec) {
550 sigevent_t event;
551
552 if (get_compat_sigevent(&event, timer_event_spec))
553 return -EFAULT;
554 return do_timer_create(which_clock, &event, created_timer_id);
555 }
556 return do_timer_create(which_clock, NULL, created_timer_id);
557}
558#endif
559
560static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
561{
562 struct k_itimer *timr;
563
564 /*
565 * timer_t could be any type >= int and we want to make sure any
566 * @timer_id outside positive int range fails lookup.
567 */
568 if ((unsigned long long)timer_id > INT_MAX)
569 return NULL;
570
571 /*
572 * The hash lookup and the timers are RCU protected.
573 *
574 * Timers are added to the hash in invalid state where
575 * timr::it_signal == NULL. timer::it_signal is only set after the
576 * rest of the initialization succeeded.
577 *
578 * Timer destruction happens in steps:
579 * 1) Set timr::it_signal to NULL with timr::it_lock held
580 * 2) Release timr::it_lock
581 * 3) Remove from the hash under hash_lock
582 * 4) Call RCU for removal after the grace period
583 *
584 * Holding rcu_read_lock() accross the lookup ensures that
585 * the timer cannot be freed.
586 *
587 * The lookup validates locklessly that timr::it_signal ==
588 * current::it_signal and timr::it_id == @timer_id. timr::it_id
589 * can't change, but timr::it_signal becomes NULL during
590 * destruction.
591 */
592 rcu_read_lock();
593 timr = posix_timer_by_id(timer_id);
594 if (timr) {
595 spin_lock_irqsave(&timr->it_lock, *flags);
596 /*
597 * Validate under timr::it_lock that timr::it_signal is
598 * still valid. Pairs with #1 above.
599 */
600 if (timr->it_signal == current->signal) {
601 rcu_read_unlock();
602 return timr;
603 }
604 spin_unlock_irqrestore(&timr->it_lock, *flags);
605 }
606 rcu_read_unlock();
607
608 return NULL;
609}
610
611static ktime_t common_hrtimer_remaining(struct k_itimer *timr, ktime_t now)
612{
613 struct hrtimer *timer = &timr->it.real.timer;
614
615 return __hrtimer_expires_remaining_adjusted(timer, now);
616}
617
618static s64 common_hrtimer_forward(struct k_itimer *timr, ktime_t now)
619{
620 struct hrtimer *timer = &timr->it.real.timer;
621
622 return hrtimer_forward(timer, now, timr->it_interval);
623}
624
625/*
626 * Get the time remaining on a POSIX.1b interval timer.
627 *
628 * Two issues to handle here:
629 *
630 * 1) The timer has a requeue pending. The return value must appear as
631 * if the timer has been requeued right now.
632 *
633 * 2) The timer is a SIGEV_NONE timer. These timers are never enqueued
634 * into the hrtimer queue and therefore never expired. Emulate expiry
635 * here taking #1 into account.
636 */
637void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
638{
639 const struct k_clock *kc = timr->kclock;
640 ktime_t now, remaining, iv;
641 bool sig_none;
642
643 sig_none = timr->it_sigev_notify == SIGEV_NONE;
644 iv = timr->it_interval;
645
646 /* interval timer ? */
647 if (iv) {
648 cur_setting->it_interval = ktime_to_timespec64(iv);
649 } else if (!timr->it_active) {
650 /*
651 * SIGEV_NONE oneshot timers are never queued and therefore
652 * timr->it_active is always false. The check below
653 * vs. remaining time will handle this case.
654 *
655 * For all other timers there is nothing to update here, so
656 * return.
657 */
658 if (!sig_none)
659 return;
660 }
661
662 now = kc->clock_get_ktime(timr->it_clock);
663
664 /*
665 * If this is an interval timer and either has requeue pending or
666 * is a SIGEV_NONE timer move the expiry time forward by intervals,
667 * so expiry is > now.
668 */
669 if (iv && (timr->it_requeue_pending & REQUEUE_PENDING || sig_none))
670 timr->it_overrun += kc->timer_forward(timr, now);
671
672 remaining = kc->timer_remaining(timr, now);
673 /*
674 * As @now is retrieved before a possible timer_forward() and
675 * cannot be reevaluated by the compiler @remaining is based on the
676 * same @now value. Therefore @remaining is consistent vs. @now.
677 *
678 * Consequently all interval timers, i.e. @iv > 0, cannot have a
679 * remaining time <= 0 because timer_forward() guarantees to move
680 * them forward so that the next timer expiry is > @now.
681 */
682 if (remaining <= 0) {
683 /*
684 * A single shot SIGEV_NONE timer must return 0, when it is
685 * expired! Timers which have a real signal delivery mode
686 * must return a remaining time greater than 0 because the
687 * signal has not yet been delivered.
688 */
689 if (!sig_none)
690 cur_setting->it_value.tv_nsec = 1;
691 } else {
692 cur_setting->it_value = ktime_to_timespec64(remaining);
693 }
694}
695
696static int do_timer_gettime(timer_t timer_id, struct itimerspec64 *setting)
697{
698 const struct k_clock *kc;
699 struct k_itimer *timr;
700 unsigned long flags;
701 int ret = 0;
702
703 timr = lock_timer(timer_id, &flags);
704 if (!timr)
705 return -EINVAL;
706
707 memset(setting, 0, sizeof(*setting));
708 kc = timr->kclock;
709 if (WARN_ON_ONCE(!kc || !kc->timer_get))
710 ret = -EINVAL;
711 else
712 kc->timer_get(timr, setting);
713
714 unlock_timer(timr, flags);
715 return ret;
716}
717
718/* Get the time remaining on a POSIX.1b interval timer. */
719SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
720 struct __kernel_itimerspec __user *, setting)
721{
722 struct itimerspec64 cur_setting;
723
724 int ret = do_timer_gettime(timer_id, &cur_setting);
725 if (!ret) {
726 if (put_itimerspec64(&cur_setting, setting))
727 ret = -EFAULT;
728 }
729 return ret;
730}
731
732#ifdef CONFIG_COMPAT_32BIT_TIME
733
734SYSCALL_DEFINE2(timer_gettime32, timer_t, timer_id,
735 struct old_itimerspec32 __user *, setting)
736{
737 struct itimerspec64 cur_setting;
738
739 int ret = do_timer_gettime(timer_id, &cur_setting);
740 if (!ret) {
741 if (put_old_itimerspec32(&cur_setting, setting))
742 ret = -EFAULT;
743 }
744 return ret;
745}
746
747#endif
748
749/**
750 * sys_timer_getoverrun - Get the number of overruns of a POSIX.1b interval timer
751 * @timer_id: The timer ID which identifies the timer
752 *
753 * The "overrun count" of a timer is one plus the number of expiration
754 * intervals which have elapsed between the first expiry, which queues the
755 * signal and the actual signal delivery. On signal delivery the "overrun
756 * count" is calculated and cached, so it can be returned directly here.
757 *
758 * As this is relative to the last queued signal the returned overrun count
759 * is meaningless outside of the signal delivery path and even there it
760 * does not accurately reflect the current state when user space evaluates
761 * it.
762 *
763 * Returns:
764 * -EINVAL @timer_id is invalid
765 * 1..INT_MAX The number of overruns related to the last delivered signal
766 */
767SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
768{
769 struct k_itimer *timr;
770 unsigned long flags;
771 int overrun;
772
773 timr = lock_timer(timer_id, &flags);
774 if (!timr)
775 return -EINVAL;
776
777 overrun = timer_overrun_to_int(timr, 0);
778 unlock_timer(timr, flags);
779
780 return overrun;
781}
782
783static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
784 bool absolute, bool sigev_none)
785{
786 struct hrtimer *timer = &timr->it.real.timer;
787 enum hrtimer_mode mode;
788
789 mode = absolute ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
790 /*
791 * Posix magic: Relative CLOCK_REALTIME timers are not affected by
792 * clock modifications, so they become CLOCK_MONOTONIC based under the
793 * hood. See hrtimer_init(). Update timr->kclock, so the generic
794 * functions which use timr->kclock->clock_get_*() work.
795 *
796 * Note: it_clock stays unmodified, because the next timer_set() might
797 * use ABSTIME, so it needs to switch back.
798 */
799 if (timr->it_clock == CLOCK_REALTIME)
800 timr->kclock = absolute ? &clock_realtime : &clock_monotonic;
801
802 hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
803 timr->it.real.timer.function = posix_timer_fn;
804
805 if (!absolute)
806 expires = ktime_add_safe(expires, timer->base->get_time());
807 hrtimer_set_expires(timer, expires);
808
809 if (!sigev_none)
810 hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
811}
812
813static int common_hrtimer_try_to_cancel(struct k_itimer *timr)
814{
815 return hrtimer_try_to_cancel(&timr->it.real.timer);
816}
817
818static void common_timer_wait_running(struct k_itimer *timer)
819{
820 hrtimer_cancel_wait_running(&timer->it.real.timer);
821}
822
823/*
824 * On PREEMPT_RT this prevents priority inversion and a potential livelock
825 * against the ksoftirqd thread in case that ksoftirqd gets preempted while
826 * executing a hrtimer callback.
827 *
828 * See the comments in hrtimer_cancel_wait_running(). For PREEMPT_RT=n this
829 * just results in a cpu_relax().
830 *
831 * For POSIX CPU timers with CONFIG_POSIX_CPU_TIMERS_TASK_WORK=n this is
832 * just a cpu_relax(). With CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y this
833 * prevents spinning on an eventually scheduled out task and a livelock
834 * when the task which tries to delete or disarm the timer has preempted
835 * the task which runs the expiry in task work context.
836 */
837static struct k_itimer *timer_wait_running(struct k_itimer *timer,
838 unsigned long *flags)
839{
840 const struct k_clock *kc = READ_ONCE(timer->kclock);
841 timer_t timer_id = READ_ONCE(timer->it_id);
842
843 /* Prevent kfree(timer) after dropping the lock */
844 rcu_read_lock();
845 unlock_timer(timer, *flags);
846
847 /*
848 * kc->timer_wait_running() might drop RCU lock. So @timer
849 * cannot be touched anymore after the function returns!
850 */
851 if (!WARN_ON_ONCE(!kc->timer_wait_running))
852 kc->timer_wait_running(timer);
853
854 rcu_read_unlock();
855 /* Relock the timer. It might be not longer hashed. */
856 return lock_timer(timer_id, flags);
857}
858
859/* Set a POSIX.1b interval timer. */
860int common_timer_set(struct k_itimer *timr, int flags,
861 struct itimerspec64 *new_setting,
862 struct itimerspec64 *old_setting)
863{
864 const struct k_clock *kc = timr->kclock;
865 bool sigev_none;
866 ktime_t expires;
867
868 if (old_setting)
869 common_timer_get(timr, old_setting);
870
871 /* Prevent rearming by clearing the interval */
872 timr->it_interval = 0;
873 /*
874 * Careful here. On SMP systems the timer expiry function could be
875 * active and spinning on timr->it_lock.
876 */
877 if (kc->timer_try_to_cancel(timr) < 0)
878 return TIMER_RETRY;
879
880 timr->it_active = 0;
881 timr->it_requeue_pending = (timr->it_requeue_pending + 2) &
882 ~REQUEUE_PENDING;
883 timr->it_overrun_last = 0;
884
885 /* Switch off the timer when it_value is zero */
886 if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
887 return 0;
888
889 timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
890 expires = timespec64_to_ktime(new_setting->it_value);
891 if (flags & TIMER_ABSTIME)
892 expires = timens_ktime_to_host(timr->it_clock, expires);
893 sigev_none = timr->it_sigev_notify == SIGEV_NONE;
894
895 kc->timer_arm(timr, expires, flags & TIMER_ABSTIME, sigev_none);
896 timr->it_active = !sigev_none;
897 return 0;
898}
899
900static int do_timer_settime(timer_t timer_id, int tmr_flags,
901 struct itimerspec64 *new_spec64,
902 struct itimerspec64 *old_spec64)
903{
904 const struct k_clock *kc;
905 struct k_itimer *timr;
906 unsigned long flags;
907 int error = 0;
908
909 if (!timespec64_valid(&new_spec64->it_interval) ||
910 !timespec64_valid(&new_spec64->it_value))
911 return -EINVAL;
912
913 if (old_spec64)
914 memset(old_spec64, 0, sizeof(*old_spec64));
915
916 timr = lock_timer(timer_id, &flags);
917retry:
918 if (!timr)
919 return -EINVAL;
920
921 kc = timr->kclock;
922 if (WARN_ON_ONCE(!kc || !kc->timer_set))
923 error = -EINVAL;
924 else
925 error = kc->timer_set(timr, tmr_flags, new_spec64, old_spec64);
926
927 if (error == TIMER_RETRY) {
928 // We already got the old time...
929 old_spec64 = NULL;
930 /* Unlocks and relocks the timer if it still exists */
931 timr = timer_wait_running(timr, &flags);
932 goto retry;
933 }
934 unlock_timer(timr, flags);
935
936 return error;
937}
938
939/* Set a POSIX.1b interval timer */
940SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
941 const struct __kernel_itimerspec __user *, new_setting,
942 struct __kernel_itimerspec __user *, old_setting)
943{
944 struct itimerspec64 new_spec, old_spec, *rtn;
945 int error = 0;
946
947 if (!new_setting)
948 return -EINVAL;
949
950 if (get_itimerspec64(&new_spec, new_setting))
951 return -EFAULT;
952
953 rtn = old_setting ? &old_spec : NULL;
954 error = do_timer_settime(timer_id, flags, &new_spec, rtn);
955 if (!error && old_setting) {
956 if (put_itimerspec64(&old_spec, old_setting))
957 error = -EFAULT;
958 }
959 return error;
960}
961
962#ifdef CONFIG_COMPAT_32BIT_TIME
963SYSCALL_DEFINE4(timer_settime32, timer_t, timer_id, int, flags,
964 struct old_itimerspec32 __user *, new,
965 struct old_itimerspec32 __user *, old)
966{
967 struct itimerspec64 new_spec, old_spec;
968 struct itimerspec64 *rtn = old ? &old_spec : NULL;
969 int error = 0;
970
971 if (!new)
972 return -EINVAL;
973 if (get_old_itimerspec32(&new_spec, new))
974 return -EFAULT;
975
976 error = do_timer_settime(timer_id, flags, &new_spec, rtn);
977 if (!error && old) {
978 if (put_old_itimerspec32(&old_spec, old))
979 error = -EFAULT;
980 }
981 return error;
982}
983#endif
984
985int common_timer_del(struct k_itimer *timer)
986{
987 const struct k_clock *kc = timer->kclock;
988
989 timer->it_interval = 0;
990 if (kc->timer_try_to_cancel(timer) < 0)
991 return TIMER_RETRY;
992 timer->it_active = 0;
993 return 0;
994}
995
996static inline int timer_delete_hook(struct k_itimer *timer)
997{
998 const struct k_clock *kc = timer->kclock;
999
1000 if (WARN_ON_ONCE(!kc || !kc->timer_del))
1001 return -EINVAL;
1002 return kc->timer_del(timer);
1003}
1004
1005/* Delete a POSIX.1b interval timer. */
1006SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
1007{
1008 struct k_itimer *timer;
1009 unsigned long flags;
1010
1011 timer = lock_timer(timer_id, &flags);
1012
1013retry_delete:
1014 if (!timer)
1015 return -EINVAL;
1016
1017 if (unlikely(timer_delete_hook(timer) == TIMER_RETRY)) {
1018 /* Unlocks and relocks the timer if it still exists */
1019 timer = timer_wait_running(timer, &flags);
1020 goto retry_delete;
1021 }
1022
1023 spin_lock(¤t->sighand->siglock);
1024 list_del(&timer->list);
1025 spin_unlock(¤t->sighand->siglock);
1026 /*
1027 * A concurrent lookup could check timer::it_signal lockless. It
1028 * will reevaluate with timer::it_lock held and observe the NULL.
1029 */
1030 WRITE_ONCE(timer->it_signal, NULL);
1031
1032 unlock_timer(timer, flags);
1033 posix_timer_unhash_and_free(timer);
1034 return 0;
1035}
1036
1037/*
1038 * Delete a timer if it is armed, remove it from the hash and schedule it
1039 * for RCU freeing.
1040 */
1041static void itimer_delete(struct k_itimer *timer)
1042{
1043 unsigned long flags;
1044
1045 /*
1046 * irqsave is required to make timer_wait_running() work.
1047 */
1048 spin_lock_irqsave(&timer->it_lock, flags);
1049
1050retry_delete:
1051 /*
1052 * Even if the timer is not longer accessible from other tasks
1053 * it still might be armed and queued in the underlying timer
1054 * mechanism. Worse, that timer mechanism might run the expiry
1055 * function concurrently.
1056 */
1057 if (timer_delete_hook(timer) == TIMER_RETRY) {
1058 /*
1059 * Timer is expired concurrently, prevent livelocks
1060 * and pointless spinning on RT.
1061 *
1062 * timer_wait_running() drops timer::it_lock, which opens
1063 * the possibility for another task to delete the timer.
1064 *
1065 * That's not possible here because this is invoked from
1066 * do_exit() only for the last thread of the thread group.
1067 * So no other task can access and delete that timer.
1068 */
1069 if (WARN_ON_ONCE(timer_wait_running(timer, &flags) != timer))
1070 return;
1071
1072 goto retry_delete;
1073 }
1074 list_del(&timer->list);
1075
1076 /*
1077 * Setting timer::it_signal to NULL is technically not required
1078 * here as nothing can access the timer anymore legitimately via
1079 * the hash table. Set it to NULL nevertheless so that all deletion
1080 * paths are consistent.
1081 */
1082 WRITE_ONCE(timer->it_signal, NULL);
1083
1084 spin_unlock_irqrestore(&timer->it_lock, flags);
1085 posix_timer_unhash_and_free(timer);
1086}
1087
1088/*
1089 * Invoked from do_exit() when the last thread of a thread group exits.
1090 * At that point no other task can access the timers of the dying
1091 * task anymore.
1092 */
1093void exit_itimers(struct task_struct *tsk)
1094{
1095 struct list_head timers;
1096 struct k_itimer *tmr;
1097
1098 if (list_empty(&tsk->signal->posix_timers))
1099 return;
1100
1101 /* Protect against concurrent read via /proc/$PID/timers */
1102 spin_lock_irq(&tsk->sighand->siglock);
1103 list_replace_init(&tsk->signal->posix_timers, &timers);
1104 spin_unlock_irq(&tsk->sighand->siglock);
1105
1106 /* The timers are not longer accessible via tsk::signal */
1107 while (!list_empty(&timers)) {
1108 tmr = list_first_entry(&timers, struct k_itimer, list);
1109 itimer_delete(tmr);
1110 }
1111}
1112
1113SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
1114 const struct __kernel_timespec __user *, tp)
1115{
1116 const struct k_clock *kc = clockid_to_kclock(which_clock);
1117 struct timespec64 new_tp;
1118
1119 if (!kc || !kc->clock_set)
1120 return -EINVAL;
1121
1122 if (get_timespec64(&new_tp, tp))
1123 return -EFAULT;
1124
1125 /*
1126 * Permission checks have to be done inside the clock specific
1127 * setter callback.
1128 */
1129 return kc->clock_set(which_clock, &new_tp);
1130}
1131
1132SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
1133 struct __kernel_timespec __user *, tp)
1134{
1135 const struct k_clock *kc = clockid_to_kclock(which_clock);
1136 struct timespec64 kernel_tp;
1137 int error;
1138
1139 if (!kc)
1140 return -EINVAL;
1141
1142 error = kc->clock_get_timespec(which_clock, &kernel_tp);
1143
1144 if (!error && put_timespec64(&kernel_tp, tp))
1145 error = -EFAULT;
1146
1147 return error;
1148}
1149
1150int do_clock_adjtime(const clockid_t which_clock, struct __kernel_timex * ktx)
1151{
1152 const struct k_clock *kc = clockid_to_kclock(which_clock);
1153
1154 if (!kc)
1155 return -EINVAL;
1156 if (!kc->clock_adj)
1157 return -EOPNOTSUPP;
1158
1159 return kc->clock_adj(which_clock, ktx);
1160}
1161
1162SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
1163 struct __kernel_timex __user *, utx)
1164{
1165 struct __kernel_timex ktx;
1166 int err;
1167
1168 if (copy_from_user(&ktx, utx, sizeof(ktx)))
1169 return -EFAULT;
1170
1171 err = do_clock_adjtime(which_clock, &ktx);
1172
1173 if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
1174 return -EFAULT;
1175
1176 return err;
1177}
1178
1179/**
1180 * sys_clock_getres - Get the resolution of a clock
1181 * @which_clock: The clock to get the resolution for
1182 * @tp: Pointer to a a user space timespec64 for storage
1183 *
1184 * POSIX defines:
1185 *
1186 * "The clock_getres() function shall return the resolution of any
1187 * clock. Clock resolutions are implementation-defined and cannot be set by
1188 * a process. If the argument res is not NULL, the resolution of the
1189 * specified clock shall be stored in the location pointed to by res. If
1190 * res is NULL, the clock resolution is not returned. If the time argument
1191 * of clock_settime() is not a multiple of res, then the value is truncated
1192 * to a multiple of res."
1193 *
1194 * Due to the various hardware constraints the real resolution can vary
1195 * wildly and even change during runtime when the underlying devices are
1196 * replaced. The kernel also can use hardware devices with different
1197 * resolutions for reading the time and for arming timers.
1198 *
1199 * The kernel therefore deviates from the POSIX spec in various aspects:
1200 *
1201 * 1) The resolution returned to user space
1202 *
1203 * For CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_BOOTTIME, CLOCK_TAI,
1204 * CLOCK_REALTIME_ALARM, CLOCK_BOOTTIME_ALAREM and CLOCK_MONOTONIC_RAW
1205 * the kernel differentiates only two cases:
1206 *
1207 * I) Low resolution mode:
1208 *
1209 * When high resolution timers are disabled at compile or runtime
1210 * the resolution returned is nanoseconds per tick, which represents
1211 * the precision at which timers expire.
1212 *
1213 * II) High resolution mode:
1214 *
1215 * When high resolution timers are enabled the resolution returned
1216 * is always one nanosecond independent of the actual resolution of
1217 * the underlying hardware devices.
1218 *
1219 * For CLOCK_*_ALARM the actual resolution depends on system
1220 * state. When system is running the resolution is the same as the
1221 * resolution of the other clocks. During suspend the actual
1222 * resolution is the resolution of the underlying RTC device which
1223 * might be way less precise than the clockevent device used during
1224 * running state.
1225 *
1226 * For CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE the resolution
1227 * returned is always nanoseconds per tick.
1228 *
1229 * For CLOCK_PROCESS_CPUTIME and CLOCK_THREAD_CPUTIME the resolution
1230 * returned is always one nanosecond under the assumption that the
1231 * underlying scheduler clock has a better resolution than nanoseconds
1232 * per tick.
1233 *
1234 * For dynamic POSIX clocks (PTP devices) the resolution returned is
1235 * always one nanosecond.
1236 *
1237 * 2) Affect on sys_clock_settime()
1238 *
1239 * The kernel does not truncate the time which is handed in to
1240 * sys_clock_settime(). The kernel internal timekeeping is always using
1241 * nanoseconds precision independent of the clocksource device which is
1242 * used to read the time from. The resolution of that device only
1243 * affects the presicion of the time returned by sys_clock_gettime().
1244 *
1245 * Returns:
1246 * 0 Success. @tp contains the resolution
1247 * -EINVAL @which_clock is not a valid clock ID
1248 * -EFAULT Copying the resolution to @tp faulted
1249 * -ENODEV Dynamic POSIX clock is not backed by a device
1250 * -EOPNOTSUPP Dynamic POSIX clock does not support getres()
1251 */
1252SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
1253 struct __kernel_timespec __user *, tp)
1254{
1255 const struct k_clock *kc = clockid_to_kclock(which_clock);
1256 struct timespec64 rtn_tp;
1257 int error;
1258
1259 if (!kc)
1260 return -EINVAL;
1261
1262 error = kc->clock_getres(which_clock, &rtn_tp);
1263
1264 if (!error && tp && put_timespec64(&rtn_tp, tp))
1265 error = -EFAULT;
1266
1267 return error;
1268}
1269
1270#ifdef CONFIG_COMPAT_32BIT_TIME
1271
1272SYSCALL_DEFINE2(clock_settime32, clockid_t, which_clock,
1273 struct old_timespec32 __user *, tp)
1274{
1275 const struct k_clock *kc = clockid_to_kclock(which_clock);
1276 struct timespec64 ts;
1277
1278 if (!kc || !kc->clock_set)
1279 return -EINVAL;
1280
1281 if (get_old_timespec32(&ts, tp))
1282 return -EFAULT;
1283
1284 return kc->clock_set(which_clock, &ts);
1285}
1286
1287SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
1288 struct old_timespec32 __user *, tp)
1289{
1290 const struct k_clock *kc = clockid_to_kclock(which_clock);
1291 struct timespec64 ts;
1292 int err;
1293
1294 if (!kc)
1295 return -EINVAL;
1296
1297 err = kc->clock_get_timespec(which_clock, &ts);
1298
1299 if (!err && put_old_timespec32(&ts, tp))
1300 err = -EFAULT;
1301
1302 return err;
1303}
1304
1305SYSCALL_DEFINE2(clock_adjtime32, clockid_t, which_clock,
1306 struct old_timex32 __user *, utp)
1307{
1308 struct __kernel_timex ktx;
1309 int err;
1310
1311 err = get_old_timex32(&ktx, utp);
1312 if (err)
1313 return err;
1314
1315 err = do_clock_adjtime(which_clock, &ktx);
1316
1317 if (err >= 0 && put_old_timex32(utp, &ktx))
1318 return -EFAULT;
1319
1320 return err;
1321}
1322
1323SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
1324 struct old_timespec32 __user *, tp)
1325{
1326 const struct k_clock *kc = clockid_to_kclock(which_clock);
1327 struct timespec64 ts;
1328 int err;
1329
1330 if (!kc)
1331 return -EINVAL;
1332
1333 err = kc->clock_getres(which_clock, &ts);
1334 if (!err && tp && put_old_timespec32(&ts, tp))
1335 return -EFAULT;
1336
1337 return err;
1338}
1339
1340#endif
1341
1342/*
1343 * sys_clock_nanosleep() for CLOCK_REALTIME and CLOCK_TAI
1344 */
1345static int common_nsleep(const clockid_t which_clock, int flags,
1346 const struct timespec64 *rqtp)
1347{
1348 ktime_t texp = timespec64_to_ktime(*rqtp);
1349
1350 return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
1351 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
1352 which_clock);
1353}
1354
1355/*
1356 * sys_clock_nanosleep() for CLOCK_MONOTONIC and CLOCK_BOOTTIME
1357 *
1358 * Absolute nanosleeps for these clocks are time-namespace adjusted.
1359 */
1360static int common_nsleep_timens(const clockid_t which_clock, int flags,
1361 const struct timespec64 *rqtp)
1362{
1363 ktime_t texp = timespec64_to_ktime(*rqtp);
1364
1365 if (flags & TIMER_ABSTIME)
1366 texp = timens_ktime_to_host(which_clock, texp);
1367
1368 return hrtimer_nanosleep(texp, flags & TIMER_ABSTIME ?
1369 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
1370 which_clock);
1371}
1372
1373SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
1374 const struct __kernel_timespec __user *, rqtp,
1375 struct __kernel_timespec __user *, rmtp)
1376{
1377 const struct k_clock *kc = clockid_to_kclock(which_clock);
1378 struct timespec64 t;
1379
1380 if (!kc)
1381 return -EINVAL;
1382 if (!kc->nsleep)
1383 return -EOPNOTSUPP;
1384
1385 if (get_timespec64(&t, rqtp))
1386 return -EFAULT;
1387
1388 if (!timespec64_valid(&t))
1389 return -EINVAL;
1390 if (flags & TIMER_ABSTIME)
1391 rmtp = NULL;
1392 current->restart_block.fn = do_no_restart_syscall;
1393 current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
1394 current->restart_block.nanosleep.rmtp = rmtp;
1395
1396 return kc->nsleep(which_clock, flags, &t);
1397}
1398
1399#ifdef CONFIG_COMPAT_32BIT_TIME
1400
1401SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
1402 struct old_timespec32 __user *, rqtp,
1403 struct old_timespec32 __user *, rmtp)
1404{
1405 const struct k_clock *kc = clockid_to_kclock(which_clock);
1406 struct timespec64 t;
1407
1408 if (!kc)
1409 return -EINVAL;
1410 if (!kc->nsleep)
1411 return -EOPNOTSUPP;
1412
1413 if (get_old_timespec32(&t, rqtp))
1414 return -EFAULT;
1415
1416 if (!timespec64_valid(&t))
1417 return -EINVAL;
1418 if (flags & TIMER_ABSTIME)
1419 rmtp = NULL;
1420 current->restart_block.fn = do_no_restart_syscall;
1421 current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
1422 current->restart_block.nanosleep.compat_rmtp = rmtp;
1423
1424 return kc->nsleep(which_clock, flags, &t);
1425}
1426
1427#endif
1428
1429static const struct k_clock clock_realtime = {
1430 .clock_getres = posix_get_hrtimer_res,
1431 .clock_get_timespec = posix_get_realtime_timespec,
1432 .clock_get_ktime = posix_get_realtime_ktime,
1433 .clock_set = posix_clock_realtime_set,
1434 .clock_adj = posix_clock_realtime_adj,
1435 .nsleep = common_nsleep,
1436 .timer_create = common_timer_create,
1437 .timer_set = common_timer_set,
1438 .timer_get = common_timer_get,
1439 .timer_del = common_timer_del,
1440 .timer_rearm = common_hrtimer_rearm,
1441 .timer_forward = common_hrtimer_forward,
1442 .timer_remaining = common_hrtimer_remaining,
1443 .timer_try_to_cancel = common_hrtimer_try_to_cancel,
1444 .timer_wait_running = common_timer_wait_running,
1445 .timer_arm = common_hrtimer_arm,
1446};
1447
1448static const struct k_clock clock_monotonic = {
1449 .clock_getres = posix_get_hrtimer_res,
1450 .clock_get_timespec = posix_get_monotonic_timespec,
1451 .clock_get_ktime = posix_get_monotonic_ktime,
1452 .nsleep = common_nsleep_timens,
1453 .timer_create = common_timer_create,
1454 .timer_set = common_timer_set,
1455 .timer_get = common_timer_get,
1456 .timer_del = common_timer_del,
1457 .timer_rearm = common_hrtimer_rearm,
1458 .timer_forward = common_hrtimer_forward,
1459 .timer_remaining = common_hrtimer_remaining,
1460 .timer_try_to_cancel = common_hrtimer_try_to_cancel,
1461 .timer_wait_running = common_timer_wait_running,
1462 .timer_arm = common_hrtimer_arm,
1463};
1464
1465static const struct k_clock clock_monotonic_raw = {
1466 .clock_getres = posix_get_hrtimer_res,
1467 .clock_get_timespec = posix_get_monotonic_raw,
1468};
1469
1470static const struct k_clock clock_realtime_coarse = {
1471 .clock_getres = posix_get_coarse_res,
1472 .clock_get_timespec = posix_get_realtime_coarse,
1473};
1474
1475static const struct k_clock clock_monotonic_coarse = {
1476 .clock_getres = posix_get_coarse_res,
1477 .clock_get_timespec = posix_get_monotonic_coarse,
1478};
1479
1480static const struct k_clock clock_tai = {
1481 .clock_getres = posix_get_hrtimer_res,
1482 .clock_get_ktime = posix_get_tai_ktime,
1483 .clock_get_timespec = posix_get_tai_timespec,
1484 .nsleep = common_nsleep,
1485 .timer_create = common_timer_create,
1486 .timer_set = common_timer_set,
1487 .timer_get = common_timer_get,
1488 .timer_del = common_timer_del,
1489 .timer_rearm = common_hrtimer_rearm,
1490 .timer_forward = common_hrtimer_forward,
1491 .timer_remaining = common_hrtimer_remaining,
1492 .timer_try_to_cancel = common_hrtimer_try_to_cancel,
1493 .timer_wait_running = common_timer_wait_running,
1494 .timer_arm = common_hrtimer_arm,
1495};
1496
1497static const struct k_clock clock_boottime = {
1498 .clock_getres = posix_get_hrtimer_res,
1499 .clock_get_ktime = posix_get_boottime_ktime,
1500 .clock_get_timespec = posix_get_boottime_timespec,
1501 .nsleep = common_nsleep_timens,
1502 .timer_create = common_timer_create,
1503 .timer_set = common_timer_set,
1504 .timer_get = common_timer_get,
1505 .timer_del = common_timer_del,
1506 .timer_rearm = common_hrtimer_rearm,
1507 .timer_forward = common_hrtimer_forward,
1508 .timer_remaining = common_hrtimer_remaining,
1509 .timer_try_to_cancel = common_hrtimer_try_to_cancel,
1510 .timer_wait_running = common_timer_wait_running,
1511 .timer_arm = common_hrtimer_arm,
1512};
1513
1514static const struct k_clock * const posix_clocks[] = {
1515 [CLOCK_REALTIME] = &clock_realtime,
1516 [CLOCK_MONOTONIC] = &clock_monotonic,
1517 [CLOCK_PROCESS_CPUTIME_ID] = &clock_process,
1518 [CLOCK_THREAD_CPUTIME_ID] = &clock_thread,
1519 [CLOCK_MONOTONIC_RAW] = &clock_monotonic_raw,
1520 [CLOCK_REALTIME_COARSE] = &clock_realtime_coarse,
1521 [CLOCK_MONOTONIC_COARSE] = &clock_monotonic_coarse,
1522 [CLOCK_BOOTTIME] = &clock_boottime,
1523 [CLOCK_REALTIME_ALARM] = &alarm_clock,
1524 [CLOCK_BOOTTIME_ALARM] = &alarm_clock,
1525 [CLOCK_TAI] = &clock_tai,
1526};
1527
1528static const struct k_clock *clockid_to_kclock(const clockid_t id)
1529{
1530 clockid_t idx = id;
1531
1532 if (id < 0) {
1533 return (id & CLOCKFD_MASK) == CLOCKFD ?
1534 &clock_posix_dynamic : &clock_posix_cpu;
1535 }
1536
1537 if (id >= ARRAY_SIZE(posix_clocks))
1538 return NULL;
1539
1540 return posix_clocks[array_index_nospec(idx, ARRAY_SIZE(posix_clocks))];
1541}
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 */
70static struct kmem_cache *posix_timers_cache;
71
72static DEFINE_HASHTABLE(posix_timers_hashtable, 9);
73static DEFINE_SPINLOCK(hash_lock);
74
75static const struct k_clock * const posix_clocks[];
76static const struct k_clock *clockid_to_kclock(const clockid_t id);
77static 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 */
134static 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
142static 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
147static 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
160static 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
168static 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
192static 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 */
198static 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 */
205static 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
211static 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 */
220static 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 */
229static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
230{
231 getrawmonotonic64(tp);
232 return 0;
233}
234
235
236static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec64 *tp)
237{
238 *tp = current_kernel_time64();
239 return 0;
240}
241
242static int posix_get_monotonic_coarse(clockid_t which_clock,
243 struct timespec64 *tp)
244{
245 *tp = get_monotonic_coarse64();
246 return 0;
247}
248
249static 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
255static int posix_get_boottime(const clockid_t which_clock, struct timespec64 *tp)
256{
257 get_monotonic_boottime64(tp);
258 return 0;
259}
260
261static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp)
262{
263 timekeeping_clocktai64(tp);
264 return 0;
265}
266
267static 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 */
277static __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
286static 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 */
310void 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
333int 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 */
368static 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
434static 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
456static 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 clear_siginfo(&tmr->sigq->info);
467 return tmr;
468}
469
470static 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
479static 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
492static 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. */
499static 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(¤t->sighand->siglock);
562 new_timer->it_signal = current->signal;
563 list_add(&new_timer->list, ¤t->signal->posix_timers);
564 spin_unlock_irq(¤t->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 */
573out:
574 release_posix_timer(new_timer, it_id_set);
575 return error;
576}
577
578SYSCALL_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
593COMPAT_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 */
615static 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
641static 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
648static 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 */
671void 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. */
722static 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. */
745SYSCALL_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
759COMPAT_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 */
782SYSCALL_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
798static 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
828static 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. */
834int 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
872static 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));
887retry:
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 */
908SYSCALL_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
931COMPAT_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
953int 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
964static 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. */
974SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
975{
976 struct k_itimer *timer;
977 unsigned long flags;
978
979retry_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(¤t->sighand->siglock);
990 list_del(&timer->list);
991 spin_unlock(¤t->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 */
1006static void itimer_delete(struct k_itimer *timer)
1007{
1008 unsigned long flags;
1009
1010retry_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 */
1032void 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
1042SYSCALL_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
1057SYSCALL_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
1075SYSCALL_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
1098SYSCALL_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
1118COMPAT_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
1133COMPAT_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
1151COMPAT_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
1175COMPAT_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 */
1197static 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
1205SYSCALL_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
1231COMPAT_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
1257static 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
1274static 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
1289static const struct k_clock clock_monotonic_raw = {
1290 .clock_getres = posix_get_hrtimer_res,
1291 .clock_get = posix_get_monotonic_raw,
1292};
1293
1294static const struct k_clock clock_realtime_coarse = {
1295 .clock_getres = posix_get_coarse_res,
1296 .clock_get = posix_get_realtime_coarse,
1297};
1298
1299static const struct k_clock clock_monotonic_coarse = {
1300 .clock_getres = posix_get_coarse_res,
1301 .clock_get = posix_get_monotonic_coarse,
1302};
1303
1304static 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
1319static 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
1334static 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
1348static 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}