kernel/time/posix-timers.c

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This source file includes following definitions.
hash
__posix_timers_find
posix_timer_by_id
posix_timer_add
unlock_timer
posix_clock_realtime_get
posix_clock_realtime_set
posix_clock_realtime_adj
posix_ktime_get_ts
posix_get_monotonic_raw
posix_get_realtime_coarse
posix_get_monotonic_coarse
posix_get_coarse_res
posix_get_boottime
posix_get_tai
posix_get_hrtimer_res
init_posix_timers
timer_overrun_to_int
common_hrtimer_rearm
posixtimer_rearm
posix_timer_event
posix_timer_fn
good_sigevent
alloc_posix_timer
k_itimer_rcu_free
release_posix_timer
common_timer_create
do_timer_create
SYSCALL_DEFINE3
COMPAT_SYSCALL_DEFINE3
__lock_timer
common_hrtimer_remaining
common_hrtimer_forward
common_timer_get
do_timer_gettime
SYSCALL_DEFINE2
SYSCALL_DEFINE2
SYSCALL_DEFINE1
common_hrtimer_arm
common_hrtimer_try_to_cancel
common_timer_wait_running
timer_wait_running
common_timer_set
do_timer_settime
SYSCALL_DEFINE4
SYSCALL_DEFINE4
common_timer_del
timer_delete_hook
SYSCALL_DEFINE1
itimer_delete
exit_itimers
SYSCALL_DEFINE2
SYSCALL_DEFINE2
do_clock_adjtime
SYSCALL_DEFINE2
SYSCALL_DEFINE2
SYSCALL_DEFINE2
SYSCALL_DEFINE2
SYSCALL_DEFINE2
SYSCALL_DEFINE2
common_nsleep
SYSCALL_DEFINE4
SYSCALL_DEFINE4
clockid_to_kclock
   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 
  34 #include "timekeeping.h"
  35 #include "posix-timers.h"
  36 
  37 /*
  38  * Management arrays for POSIX timers. Timers are now kept in static hash table
  39  * with 512 entries.
  40  * Timer ids are allocated by local routine, which selects proper hash head by
  41  * key, constructed from current->signal address and per signal struct counter.
  42  * This keeps timer ids unique per process, but now they can intersect between
  43  * processes.
  44  */
  45 
  46 /*
  47  * Lets keep our timers in a slab cache :-)
  48  */
  49 static struct kmem_cache *posix_timers_cache;
  50 
  51 static DEFINE_HASHTABLE(posix_timers_hashtable, 9);
  52 static DEFINE_SPINLOCK(hash_lock);
  53 
  54 static const struct k_clock * const posix_clocks[];
  55 static const struct k_clock *clockid_to_kclock(const clockid_t id);
  56 static const struct k_clock clock_realtime, clock_monotonic;
  57 
  58 /*
  59  * we assume that the new SIGEV_THREAD_ID shares no bits with the other
  60  * SIGEV values.  Here we put out an error if this assumption fails.
  61  */
  62 #if SIGEV_THREAD_ID != (SIGEV_THREAD_ID & \
  63                        ~(SIGEV_SIGNAL | SIGEV_NONE | SIGEV_THREAD))
  64 #error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
  65 #endif
  66 
  67 /*
  68  * The timer ID is turned into a timer address by idr_find().
  69  * Verifying a valid ID consists of:
  70  *
  71  * a) checking that idr_find() returns other than -1.
  72  * b) checking that the timer id matches the one in the timer itself.
  73  * c) that the timer owner is in the callers thread group.
  74  */
  75 
  76 /*
  77  * CLOCKs: The POSIX standard calls for a couple of clocks and allows us
  78  *          to implement others.  This structure defines the various
  79  *          clocks.
  80  *
  81  * RESOLUTION: Clock resolution is used to round up timer and interval
  82  *          times, NOT to report clock times, which are reported with as
  83  *          much resolution as the system can muster.  In some cases this
  84  *          resolution may depend on the underlying clock hardware and
  85  *          may not be quantifiable until run time, and only then is the
  86  *          necessary code is written.  The standard says we should say
  87  *          something about this issue in the documentation...
  88  *
  89  * FUNCTIONS: The CLOCKs structure defines possible functions to
  90  *          handle various clock functions.
  91  *
  92  *          The standard POSIX timer management code assumes the
  93  *          following: 1.) The k_itimer struct (sched.h) is used for
  94  *          the timer.  2.) The list, it_lock, it_clock, it_id and
  95  *          it_pid fields are not modified by timer code.
  96  *
  97  * Permissions: It is assumed that the clock_settime() function defined
  98  *          for each clock will take care of permission checks.  Some
  99  *          clocks may be set able by any user (i.e. local process
 100  *          clocks) others not.  Currently the only set able clock we
 101  *          have is CLOCK_REALTIME and its high res counter part, both of
 102  *          which we beg off on and pass to do_sys_settimeofday().
 103  */
 104 static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags);
 105 
 106 #define lock_timer(tid, flags)                                             \
 107 ({      struct k_itimer *__timr;                                           \
 108         __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags));  \
 109         __timr;                                                            \
 110 })
 111 
 112 static int hash(struct signal_struct *sig, unsigned int nr)
 113 {
 114         return hash_32(hash32_ptr(sig) ^ nr, HASH_BITS(posix_timers_hashtable));
 115 }
 116 
 117 static struct k_itimer *__posix_timers_find(struct hlist_head *head,
 118                                             struct signal_struct *sig,
 119                                             timer_t id)
 120 {
 121         struct k_itimer *timer;
 122 
 123         hlist_for_each_entry_rcu(timer, head, t_hash) {
 124                 if ((timer->it_signal == sig) && (timer->it_id == id))
 125                         return timer;
 126         }
 127         return NULL;
 128 }
 129 
 130 static struct k_itimer *posix_timer_by_id(timer_t id)
 131 {
 132         struct signal_struct *sig = current->signal;
 133         struct hlist_head *head = &posix_timers_hashtable[hash(sig, id)];
 134 
 135         return __posix_timers_find(head, sig, id);
 136 }
 137 
 138 static int posix_timer_add(struct k_itimer *timer)
 139 {
 140         struct signal_struct *sig = current->signal;
 141         int first_free_id = sig->posix_timer_id;
 142         struct hlist_head *head;
 143         int ret = -ENOENT;
 144 
 145         do {
 146                 spin_lock(&hash_lock);
 147                 head = &posix_timers_hashtable[hash(sig, sig->posix_timer_id)];
 148                 if (!__posix_timers_find(head, sig, sig->posix_timer_id)) {
 149                         hlist_add_head_rcu(&timer->t_hash, head);
 150                         ret = sig->posix_timer_id;
 151                 }
 152                 if (++sig->posix_timer_id < 0)
 153                         sig->posix_timer_id = 0;
 154                 if ((sig->posix_timer_id == first_free_id) && (ret == -ENOENT))
 155                         /* Loop over all possible ids completed */
 156                         ret = -EAGAIN;
 157                 spin_unlock(&hash_lock);
 158         } while (ret == -ENOENT);
 159         return ret;
 160 }
 161 
 162 static inline void unlock_timer(struct k_itimer *timr, unsigned long flags)
 163 {
 164         spin_unlock_irqrestore(&timr->it_lock, flags);
 165 }
 166 
 167 /* Get clock_realtime */
 168 static int posix_clock_realtime_get(clockid_t which_clock, struct timespec64 *tp)
 169 {
 170         ktime_get_real_ts64(tp);
 171         return 0;
 172 }
 173 
 174 /* Set clock_realtime */
 175 static int posix_clock_realtime_set(const clockid_t which_clock,
 176                                     const struct timespec64 *tp)
 177 {
 178         return do_sys_settimeofday64(tp, NULL);
 179 }
 180 
 181 static int posix_clock_realtime_adj(const clockid_t which_clock,
 182                                     struct __kernel_timex *t)
 183 {
 184         return do_adjtimex(t);
 185 }
 186 
 187 /*
 188  * Get monotonic time for posix timers
 189  */
 190 static int posix_ktime_get_ts(clockid_t which_clock, struct timespec64 *tp)
 191 {
 192         ktime_get_ts64(tp);
 193         return 0;
 194 }
 195 
 196 /*
 197  * Get monotonic-raw time for posix timers
 198  */
 199 static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec64 *tp)
 200 {
 201         ktime_get_raw_ts64(tp);
 202         return 0;
 203 }
 204 
 205 
 206 static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec64 *tp)
 207 {
 208         ktime_get_coarse_real_ts64(tp);
 209         return 0;
 210 }
 211 
 212 static int posix_get_monotonic_coarse(clockid_t which_clock,
 213                                                 struct timespec64 *tp)
 214 {
 215         ktime_get_coarse_ts64(tp);
 216         return 0;
 217 }
 218 
 219 static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 *tp)
 220 {
 221         *tp = ktime_to_timespec64(KTIME_LOW_RES);
 222         return 0;
 223 }
 224 
 225 static int posix_get_boottime(const clockid_t which_clock, struct timespec64 *tp)
 226 {
 227         ktime_get_boottime_ts64(tp);
 228         return 0;
 229 }
 230 
 231 static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp)
 232 {
 233         ktime_get_clocktai_ts64(tp);
 234         return 0;
 235 }
 236 
 237 static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp)
 238 {
 239         tp->tv_sec = 0;
 240         tp->tv_nsec = hrtimer_resolution;
 241         return 0;
 242 }
 243 
 244 /*
 245  * Initialize everything, well, just everything in Posix clocks/timers ;)
 246  */
 247 static __init int init_posix_timers(void)
 248 {
 249         posix_timers_cache = kmem_cache_create("posix_timers_cache",
 250                                         sizeof (struct k_itimer), 0, SLAB_PANIC,
 251                                         NULL);
 252         return 0;
 253 }
 254 __initcall(init_posix_timers);
 255 
 256 /*
 257  * The siginfo si_overrun field and the return value of timer_getoverrun(2)
 258  * are of type int. Clamp the overrun value to INT_MAX
 259  */
 260 static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
 261 {
 262         s64 sum = timr->it_overrun_last + (s64)baseval;
 263 
 264         return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
 265 }
 266 
 267 static void common_hrtimer_rearm(struct k_itimer *timr)
 268 {
 269         struct hrtimer *timer = &timr->it.real.timer;
 270 
 271         timr->it_overrun += hrtimer_forward(timer, timer->base->get_time(),
 272                                             timr->it_interval);
 273         hrtimer_restart(timer);
 274 }
 275 
 276 /*
 277  * This function is exported for use by the signal deliver code.  It is
 278  * called just prior to the info block being released and passes that
 279  * block to us.  It's function is to update the overrun entry AND to
 280  * restart the timer.  It should only be called if the timer is to be
 281  * restarted (i.e. we have flagged this in the sys_private entry of the
 282  * info block).
 283  *
 284  * To protect against the timer going away while the interrupt is queued,
 285  * we require that the it_requeue_pending flag be set.
 286  */
 287 void posixtimer_rearm(struct kernel_siginfo *info)
 288 {
 289         struct k_itimer *timr;
 290         unsigned long flags;
 291 
 292         timr = lock_timer(info->si_tid, &flags);
 293         if (!timr)
 294                 return;
 295 
 296         if (timr->it_interval && timr->it_requeue_pending == info->si_sys_private) {
 297                 timr->kclock->timer_rearm(timr);
 298 
 299                 timr->it_active = 1;
 300                 timr->it_overrun_last = timr->it_overrun;
 301                 timr->it_overrun = -1LL;
 302                 ++timr->it_requeue_pending;
 303 
 304                 info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
 305         }
 306 
 307         unlock_timer(timr, flags);
 308 }
 309 
 310 int posix_timer_event(struct k_itimer *timr, int si_private)
 311 {
 312         enum pid_type type;
 313         int ret = -1;
 314         /*
 315          * FIXME: if ->sigq is queued we can race with
 316          * dequeue_signal()->posixtimer_rearm().
 317          *
 318          * If dequeue_signal() sees the "right" value of
 319          * si_sys_private it calls posixtimer_rearm().
 320          * We re-queue ->sigq and drop ->it_lock().
 321          * posixtimer_rearm() locks the timer
 322          * and re-schedules it while ->sigq is pending.
 323          * Not really bad, but not that we want.
 324          */
 325         timr->sigq->info.si_sys_private = si_private;
 326 
 327         type = !(timr->it_sigev_notify & SIGEV_THREAD_ID) ? PIDTYPE_TGID : PIDTYPE_PID;
 328         ret = send_sigqueue(timr->sigq, timr->it_pid, type);
 329         /* If we failed to send the signal the timer stops. */
 330         return ret > 0;
 331 }
 332 
 333 /*
 334  * This function gets called when a POSIX.1b interval timer expires.  It
 335  * is used as a callback from the kernel internal timer.  The
 336  * run_timer_list code ALWAYS calls with interrupts on.
 337 
 338  * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
 339  */
 340 static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
 341 {
 342         struct k_itimer *timr;
 343         unsigned long flags;
 344         int si_private = 0;
 345         enum hrtimer_restart ret = HRTIMER_NORESTART;
 346 
 347         timr = container_of(timer, struct k_itimer, it.real.timer);
 348         spin_lock_irqsave(&timr->it_lock, flags);
 349 
 350         timr->it_active = 0;
 351         if (timr->it_interval != 0)
 352                 si_private = ++timr->it_requeue_pending;
 353 
 354         if (posix_timer_event(timr, si_private)) {
 355                 /*
 356                  * signal was not sent because of sig_ignor
 357                  * we will not get a call back to restart it AND
 358                  * it should be restarted.
 359                  */
 360                 if (timr->it_interval != 0) {
 361                         ktime_t now = hrtimer_cb_get_time(timer);
 362 
 363                         /*
 364                          * FIXME: What we really want, is to stop this
 365                          * timer completely and restart it in case the
 366                          * SIG_IGN is removed. This is a non trivial
 367                          * change which involves sighand locking
 368                          * (sigh !), which we don't want to do late in
 369                          * the release cycle.
 370                          *
 371                          * For now we just let timers with an interval
 372                          * less than a jiffie expire every jiffie to
 373                          * avoid softirq starvation in case of SIG_IGN
 374                          * and a very small interval, which would put
 375                          * the timer right back on the softirq pending
 376                          * list. By moving now ahead of time we trick
 377                          * hrtimer_forward() to expire the timer
 378                          * later, while we still maintain the overrun
 379                          * accuracy, but have some inconsistency in
 380                          * the timer_gettime() case. This is at least
 381                          * better than a starved softirq. A more
 382                          * complex fix which solves also another related
 383                          * inconsistency is already in the pipeline.
 384                          */
 385 #ifdef CONFIG_HIGH_RES_TIMERS
 386                         {
 387                                 ktime_t kj = NSEC_PER_SEC / HZ;
 388 
 389                                 if (timr->it_interval < kj)
 390                                         now = ktime_add(now, kj);
 391                         }
 392 #endif
 393                         timr->it_overrun += hrtimer_forward(timer, now,
 394                                                             timr->it_interval);
 395                         ret = HRTIMER_RESTART;
 396                         ++timr->it_requeue_pending;
 397                         timr->it_active = 1;
 398                 }
 399         }
 400 
 401         unlock_timer(timr, flags);
 402         return ret;
 403 }
 404 
 405 static struct pid *good_sigevent(sigevent_t * event)
 406 {
 407         struct pid *pid = task_tgid(current);
 408         struct task_struct *rtn;
 409 
 410         switch (event->sigev_notify) {
 411         case SIGEV_SIGNAL | SIGEV_THREAD_ID:
 412                 pid = find_vpid(event->sigev_notify_thread_id);
 413                 rtn = pid_task(pid, PIDTYPE_PID);
 414                 if (!rtn || !same_thread_group(rtn, current))
 415                         return NULL;
 416                 /* FALLTHRU */
 417         case SIGEV_SIGNAL:
 418         case SIGEV_THREAD:
 419                 if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
 420                         return NULL;
 421                 /* FALLTHRU */
 422         case SIGEV_NONE:
 423                 return pid;
 424         default:
 425                 return NULL;
 426         }
 427 }
 428 
 429 static struct k_itimer * alloc_posix_timer(void)
 430 {
 431         struct k_itimer *tmr;
 432         tmr = kmem_cache_zalloc(posix_timers_cache, GFP_KERNEL);
 433         if (!tmr)
 434                 return tmr;
 435         if (unlikely(!(tmr->sigq = sigqueue_alloc()))) {
 436                 kmem_cache_free(posix_timers_cache, tmr);
 437                 return NULL;
 438         }
 439         clear_siginfo(&tmr->sigq->info);
 440         return tmr;
 441 }
 442 
 443 static void k_itimer_rcu_free(struct rcu_head *head)
 444 {
 445         struct k_itimer *tmr = container_of(head, struct k_itimer, rcu);
 446 
 447         kmem_cache_free(posix_timers_cache, tmr);
 448 }
 449 
 450 #define IT_ID_SET       1
 451 #define IT_ID_NOT_SET   0
 452 static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
 453 {
 454         if (it_id_set) {
 455                 unsigned long flags;
 456                 spin_lock_irqsave(&hash_lock, flags);
 457                 hlist_del_rcu(&tmr->t_hash);
 458                 spin_unlock_irqrestore(&hash_lock, flags);
 459         }
 460         put_pid(tmr->it_pid);
 461         sigqueue_free(tmr->sigq);
 462         call_rcu(&tmr->rcu, k_itimer_rcu_free);
 463 }
 464 
 465 static int common_timer_create(struct k_itimer *new_timer)
 466 {
 467         hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
 468         return 0;
 469 }
 470 
 471 /* Create a POSIX.1b interval timer. */
 472 static int do_timer_create(clockid_t which_clock, struct sigevent *event,
 473                            timer_t __user *created_timer_id)
 474 {
 475         const struct k_clock *kc = clockid_to_kclock(which_clock);
 476         struct k_itimer *new_timer;
 477         int error, new_timer_id;
 478         int it_id_set = IT_ID_NOT_SET;
 479 
 480         if (!kc)
 481                 return -EINVAL;
 482         if (!kc->timer_create)
 483                 return -EOPNOTSUPP;
 484 
 485         new_timer = alloc_posix_timer();
 486         if (unlikely(!new_timer))
 487                 return -EAGAIN;
 488 
 489         spin_lock_init(&new_timer->it_lock);
 490         new_timer_id = posix_timer_add(new_timer);
 491         if (new_timer_id < 0) {
 492                 error = new_timer_id;
 493                 goto out;
 494         }
 495 
 496         it_id_set = IT_ID_SET;
 497         new_timer->it_id = (timer_t) new_timer_id;
 498         new_timer->it_clock = which_clock;
 499         new_timer->kclock = kc;
 500         new_timer->it_overrun = -1LL;
 501 
 502         if (event) {
 503                 rcu_read_lock();
 504                 new_timer->it_pid = get_pid(good_sigevent(event));
 505                 rcu_read_unlock();
 506                 if (!new_timer->it_pid) {
 507                         error = -EINVAL;
 508                         goto out;
 509                 }
 510                 new_timer->it_sigev_notify     = event->sigev_notify;
 511                 new_timer->sigq->info.si_signo = event->sigev_signo;
 512                 new_timer->sigq->info.si_value = event->sigev_value;
 513         } else {
 514                 new_timer->it_sigev_notify     = SIGEV_SIGNAL;
 515                 new_timer->sigq->info.si_signo = SIGALRM;
 516                 memset(&new_timer->sigq->info.si_value, 0, sizeof(sigval_t));
 517                 new_timer->sigq->info.si_value.sival_int = new_timer->it_id;
 518                 new_timer->it_pid = get_pid(task_tgid(current));
 519         }
 520 
 521         new_timer->sigq->info.si_tid   = new_timer->it_id;
 522         new_timer->sigq->info.si_code  = SI_TIMER;
 523 
 524         if (copy_to_user(created_timer_id,
 525                          &new_timer_id, sizeof (new_timer_id))) {
 526                 error = -EFAULT;
 527                 goto out;
 528         }
 529 
 530         error = kc->timer_create(new_timer);
 531         if (error)
 532                 goto out;
 533 
 534         spin_lock_irq(&current->sighand->siglock);
 535         new_timer->it_signal = current->signal;
 536         list_add(&new_timer->list, &current->signal->posix_timers);
 537         spin_unlock_irq(&current->sighand->siglock);
 538 
 539         return 0;
 540         /*
 541          * In the case of the timer belonging to another task, after
 542          * the task is unlocked, the timer is owned by the other task
 543          * and may cease to exist at any time.  Don't use or modify
 544          * new_timer after the unlock call.
 545          */
 546 out:
 547         release_posix_timer(new_timer, it_id_set);
 548         return error;
 549 }
 550 
 551 SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
 552                 struct sigevent __user *, timer_event_spec,
 553                 timer_t __user *, created_timer_id)
 554 {
 555         if (timer_event_spec) {
 556                 sigevent_t event;
 557 
 558                 if (copy_from_user(&event, timer_event_spec, sizeof (event)))
 559                         return -EFAULT;
 560                 return do_timer_create(which_clock, &event, created_timer_id);
 561         }
 562         return do_timer_create(which_clock, NULL, created_timer_id);
 563 }
 564 
 565 #ifdef CONFIG_COMPAT
 566 COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
 567                        struct compat_sigevent __user *, timer_event_spec,
 568                        timer_t __user *, created_timer_id)
 569 {
 570         if (timer_event_spec) {
 571                 sigevent_t event;
 572 
 573                 if (get_compat_sigevent(&event, timer_event_spec))
 574                         return -EFAULT;
 575                 return do_timer_create(which_clock, &event, created_timer_id);
 576         }
 577         return do_timer_create(which_clock, NULL, created_timer_id);
 578 }
 579 #endif
 580 
 581 /*
 582  * Locking issues: We need to protect the result of the id look up until
 583  * we get the timer locked down so it is not deleted under us.  The
 584  * removal is done under the idr spinlock so we use that here to bridge
 585  * the find to the timer lock.  To avoid a dead lock, the timer id MUST
 586  * be release with out holding the timer lock.
 587  */
 588 static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
 589 {
 590         struct k_itimer *timr;
 591 
 592         /*
 593          * timer_t could be any type >= int and we want to make sure any
 594          * @timer_id outside positive int range fails lookup.
 595          */
 596         if ((unsigned long long)timer_id > INT_MAX)
 597                 return NULL;
 598 
 599         rcu_read_lock();
 600         timr = posix_timer_by_id(timer_id);
 601         if (timr) {
 602                 spin_lock_irqsave(&timr->it_lock, *flags);
 603                 if (timr->it_signal == current->signal) {
 604                         rcu_read_unlock();
 605                         return timr;
 606                 }
 607                 spin_unlock_irqrestore(&timr->it_lock, *flags);
 608         }
 609         rcu_read_unlock();
 610 
 611         return NULL;
 612 }
 613 
 614 static ktime_t common_hrtimer_remaining(struct k_itimer *timr, ktime_t now)
 615 {
 616         struct hrtimer *timer = &timr->it.real.timer;
 617 
 618         return __hrtimer_expires_remaining_adjusted(timer, now);
 619 }
 620 
 621 static s64 common_hrtimer_forward(struct k_itimer *timr, ktime_t now)
 622 {
 623         struct hrtimer *timer = &timr->it.real.timer;
 624 
 625         return hrtimer_forward(timer, now, timr->it_interval);
 626 }
 627 
 628 /*
 629  * Get the time remaining on a POSIX.1b interval timer.  This function
 630  * is ALWAYS called with spin_lock_irq on the timer, thus it must not
 631  * mess with irq.
 632  *
 633  * We have a couple of messes to clean up here.  First there is the case
 634  * of a timer that has a requeue pending.  These timers should appear to
 635  * be in the timer list with an expiry as if we were to requeue them
 636  * now.
 637  *
 638  * The second issue is the SIGEV_NONE timer which may be active but is
 639  * not really ever put in the timer list (to save system resources).
 640  * This timer may be expired, and if so, we will do it here.  Otherwise
 641  * it is the same as a requeue pending timer WRT to what we should
 642  * report.
 643  */
 644 void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
 645 {
 646         const struct k_clock *kc = timr->kclock;
 647         ktime_t now, remaining, iv;
 648         struct timespec64 ts64;
 649         bool sig_none;
 650 
 651         sig_none = timr->it_sigev_notify == SIGEV_NONE;
 652         iv = timr->it_interval;
 653 
 654         /* interval timer ? */
 655         if (iv) {
 656                 cur_setting->it_interval = ktime_to_timespec64(iv);
 657         } else if (!timr->it_active) {
 658                 /*
 659                  * SIGEV_NONE oneshot timers are never queued. Check them
 660                  * below.
 661                  */
 662                 if (!sig_none)
 663                         return;
 664         }
 665 
 666         /*
 667          * The timespec64 based conversion is suboptimal, but it's not
 668          * worth to implement yet another callback.
 669          */
 670         kc->clock_get(timr->it_clock, &ts64);
 671         now = timespec64_to_ktime(ts64);
 672 
 673         /*
 674          * When a requeue is pending or this is a SIGEV_NONE timer move the
 675          * expiry time forward by intervals, so expiry is > now.
 676          */
 677         if (iv && (timr->it_requeue_pending & REQUEUE_PENDING || sig_none))
 678                 timr->it_overrun += kc->timer_forward(timr, now);
 679 
 680         remaining = kc->timer_remaining(timr, now);
 681         /* Return 0 only, when the timer is expired and not pending */
 682         if (remaining <= 0) {
 683                 /*
 684                  * A single shot SIGEV_NONE timer must return 0, when
 685                  * it is expired !
 686                  */
 687                 if (!sig_none)
 688                         cur_setting->it_value.tv_nsec = 1;
 689         } else {
 690                 cur_setting->it_value = ktime_to_timespec64(remaining);
 691         }
 692 }
 693 
 694 /* Get the time remaining on a POSIX.1b interval timer. */
 695 static int do_timer_gettime(timer_t timer_id,  struct itimerspec64 *setting)
 696 {
 697         struct k_itimer *timr;
 698         const struct k_clock *kc;
 699         unsigned long flags;
 700         int ret = 0;
 701 
 702         timr = lock_timer(timer_id, &flags);
 703         if (!timr)
 704                 return -EINVAL;
 705 
 706         memset(setting, 0, sizeof(*setting));
 707         kc = timr->kclock;
 708         if (WARN_ON_ONCE(!kc || !kc->timer_get))
 709                 ret = -EINVAL;
 710         else
 711                 kc->timer_get(timr, setting);
 712 
 713         unlock_timer(timr, flags);
 714         return ret;
 715 }
 716 
 717 /* Get the time remaining on a POSIX.1b interval timer. */
 718 SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
 719                 struct __kernel_itimerspec __user *, setting)
 720 {
 721         struct itimerspec64 cur_setting;
 722 
 723         int ret = do_timer_gettime(timer_id, &cur_setting);
 724         if (!ret) {
 725                 if (put_itimerspec64(&cur_setting, setting))
 726                         ret = -EFAULT;
 727         }
 728         return ret;
 729 }
 730 
 731 #ifdef CONFIG_COMPAT_32BIT_TIME
 732 
 733 SYSCALL_DEFINE2(timer_gettime32, timer_t, timer_id,
 734                 struct old_itimerspec32 __user *, setting)
 735 {
 736         struct itimerspec64 cur_setting;
 737 
 738         int ret = do_timer_gettime(timer_id, &cur_setting);
 739         if (!ret) {
 740                 if (put_old_itimerspec32(&cur_setting, setting))
 741                         ret = -EFAULT;
 742         }
 743         return ret;
 744 }
 745 
 746 #endif
 747 
 748 /*
 749  * Get the number of overruns of a POSIX.1b interval timer.  This is to
 750  * be the overrun of the timer last delivered.  At the same time we are
 751  * accumulating overruns on the next timer.  The overrun is frozen when
 752  * the signal is delivered, either at the notify time (if the info block
 753  * is not queued) or at the actual delivery time (as we are informed by
 754  * the call back to posixtimer_rearm().  So all we need to do is
 755  * to pick up the frozen overrun.
 756  */
 757 SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
 758 {
 759         struct k_itimer *timr;
 760         int overrun;
 761         unsigned long flags;
 762 
 763         timr = lock_timer(timer_id, &flags);
 764         if (!timr)
 765                 return -EINVAL;
 766 
 767         overrun = timer_overrun_to_int(timr, 0);
 768         unlock_timer(timr, flags);
 769 
 770         return overrun;
 771 }
 772 
 773 static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
 774                                bool absolute, bool sigev_none)
 775 {
 776         struct hrtimer *timer = &timr->it.real.timer;
 777         enum hrtimer_mode mode;
 778 
 779         mode = absolute ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
 780         /*
 781          * Posix magic: Relative CLOCK_REALTIME timers are not affected by
 782          * clock modifications, so they become CLOCK_MONOTONIC based under the
 783          * hood. See hrtimer_init(). Update timr->kclock, so the generic
 784          * functions which use timr->kclock->clock_get() work.
 785          *
 786          * Note: it_clock stays unmodified, because the next timer_set() might
 787          * use ABSTIME, so it needs to switch back.
 788          */
 789         if (timr->it_clock == CLOCK_REALTIME)
 790                 timr->kclock = absolute ? &clock_realtime : &clock_monotonic;
 791 
 792         hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
 793         timr->it.real.timer.function = posix_timer_fn;
 794 
 795         if (!absolute)
 796                 expires = ktime_add_safe(expires, timer->base->get_time());
 797         hrtimer_set_expires(timer, expires);
 798 
 799         if (!sigev_none)
 800                 hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
 801 }
 802 
 803 static int common_hrtimer_try_to_cancel(struct k_itimer *timr)
 804 {
 805         return hrtimer_try_to_cancel(&timr->it.real.timer);
 806 }
 807 
 808 static void common_timer_wait_running(struct k_itimer *timer)
 809 {
 810         hrtimer_cancel_wait_running(&timer->it.real.timer);
 811 }
 812 
 813 /*
 814  * On PREEMPT_RT this prevent priority inversion against softirq kthread in
 815  * case it gets preempted while executing a timer callback. See comments in
 816  * hrtimer_cancel_wait_running. For PREEMPT_RT=n this just results in a
 817  * cpu_relax().
 818  */
 819 static struct k_itimer *timer_wait_running(struct k_itimer *timer,
 820                                            unsigned long *flags)
 821 {
 822         const struct k_clock *kc = READ_ONCE(timer->kclock);
 823         timer_t timer_id = READ_ONCE(timer->it_id);
 824 
 825         /* Prevent kfree(timer) after dropping the lock */
 826         rcu_read_lock();
 827         unlock_timer(timer, *flags);
 828 
 829         if (!WARN_ON_ONCE(!kc->timer_wait_running))
 830                 kc->timer_wait_running(timer);
 831 
 832         rcu_read_unlock();
 833         /* Relock the timer. It might be not longer hashed. */
 834         return lock_timer(timer_id, flags);
 835 }
 836 
 837 /* Set a POSIX.1b interval timer. */
 838 int common_timer_set(struct k_itimer *timr, int flags,
 839                      struct itimerspec64 *new_setting,
 840                      struct itimerspec64 *old_setting)
 841 {
 842         const struct k_clock *kc = timr->kclock;
 843         bool sigev_none;
 844         ktime_t expires;
 845 
 846         if (old_setting)
 847                 common_timer_get(timr, old_setting);
 848 
 849         /* Prevent rearming by clearing the interval */
 850         timr->it_interval = 0;
 851         /*
 852          * Careful here. On SMP systems the timer expiry function could be
 853          * active and spinning on timr->it_lock.
 854          */
 855         if (kc->timer_try_to_cancel(timr) < 0)
 856                 return TIMER_RETRY;
 857 
 858         timr->it_active = 0;
 859         timr->it_requeue_pending = (timr->it_requeue_pending + 2) &
 860                 ~REQUEUE_PENDING;
 861         timr->it_overrun_last = 0;
 862 
 863         /* Switch off the timer when it_value is zero */
 864         if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
 865                 return 0;
 866 
 867         timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
 868         expires = timespec64_to_ktime(new_setting->it_value);
 869         sigev_none = timr->it_sigev_notify == SIGEV_NONE;
 870 
 871         kc->timer_arm(timr, expires, flags & TIMER_ABSTIME, sigev_none);
 872         timr->it_active = !sigev_none;
 873         return 0;
 874 }
 875 
 876 static int do_timer_settime(timer_t timer_id, int tmr_flags,
 877                             struct itimerspec64 *new_spec64,
 878                             struct itimerspec64 *old_spec64)
 879 {
 880         const struct k_clock *kc;
 881         struct k_itimer *timr;
 882         unsigned long flags;
 883         int error = 0;
 884 
 885         if (!timespec64_valid(&new_spec64->it_interval) ||
 886             !timespec64_valid(&new_spec64->it_value))
 887                 return -EINVAL;
 888 
 889         if (old_spec64)
 890                 memset(old_spec64, 0, sizeof(*old_spec64));
 891 
 892         timr = lock_timer(timer_id, &flags);
 893 retry:
 894         if (!timr)
 895                 return -EINVAL;
 896 
 897         kc = timr->kclock;
 898         if (WARN_ON_ONCE(!kc || !kc->timer_set))
 899                 error = -EINVAL;
 900         else
 901                 error = kc->timer_set(timr, tmr_flags, new_spec64, old_spec64);
 902 
 903         if (error == TIMER_RETRY) {
 904                 // We already got the old time...
 905                 old_spec64 = NULL;
 906                 /* Unlocks and relocks the timer if it still exists */
 907                 timr = timer_wait_running(timr, &flags);
 908                 goto retry;
 909         }
 910         unlock_timer(timr, flags);
 911 
 912         return error;
 913 }
 914 
 915 /* Set a POSIX.1b interval timer */
 916 SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
 917                 const struct __kernel_itimerspec __user *, new_setting,
 918                 struct __kernel_itimerspec __user *, old_setting)
 919 {
 920         struct itimerspec64 new_spec, old_spec;
 921         struct itimerspec64 *rtn = old_setting ? &old_spec : NULL;
 922         int error = 0;
 923 
 924         if (!new_setting)
 925                 return -EINVAL;
 926 
 927         if (get_itimerspec64(&new_spec, new_setting))
 928                 return -EFAULT;
 929 
 930         error = do_timer_settime(timer_id, flags, &new_spec, rtn);
 931         if (!error && old_setting) {
 932                 if (put_itimerspec64(&old_spec, old_setting))
 933                         error = -EFAULT;
 934         }
 935         return error;
 936 }
 937 
 938 #ifdef CONFIG_COMPAT_32BIT_TIME
 939 SYSCALL_DEFINE4(timer_settime32, timer_t, timer_id, int, flags,
 940                 struct old_itimerspec32 __user *, new,
 941                 struct old_itimerspec32 __user *, old)
 942 {
 943         struct itimerspec64 new_spec, old_spec;
 944         struct itimerspec64 *rtn = old ? &old_spec : NULL;
 945         int error = 0;
 946 
 947         if (!new)
 948                 return -EINVAL;
 949         if (get_old_itimerspec32(&new_spec, new))
 950                 return -EFAULT;
 951 
 952         error = do_timer_settime(timer_id, flags, &new_spec, rtn);
 953         if (!error && old) {
 954                 if (put_old_itimerspec32(&old_spec, old))
 955                         error = -EFAULT;
 956         }
 957         return error;
 958 }
 959 #endif
 960 
 961 int common_timer_del(struct k_itimer *timer)
 962 {
 963         const struct k_clock *kc = timer->kclock;
 964 
 965         timer->it_interval = 0;
 966         if (kc->timer_try_to_cancel(timer) < 0)
 967                 return TIMER_RETRY;
 968         timer->it_active = 0;
 969         return 0;
 970 }
 971 
 972 static inline int timer_delete_hook(struct k_itimer *timer)
 973 {
 974         const struct k_clock *kc = timer->kclock;
 975 
 976         if (WARN_ON_ONCE(!kc || !kc->timer_del))
 977                 return -EINVAL;
 978         return kc->timer_del(timer);
 979 }
 980 
 981 /* Delete a POSIX.1b interval timer. */
 982 SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
 983 {
 984         struct k_itimer *timer;
 985         unsigned long flags;
 986 
 987         timer = lock_timer(timer_id, &flags);
 988 
 989 retry_delete:
 990         if (!timer)
 991                 return -EINVAL;
 992 
 993         if (unlikely(timer_delete_hook(timer) == TIMER_RETRY)) {
 994                 /* Unlocks and relocks the timer if it still exists */
 995                 timer = timer_wait_running(timer, &flags);
 996                 goto retry_delete;
 997         }
 998 
 999         spin_lock(&current->sighand->siglock);
1000         list_del(&timer->list);
1001         spin_unlock(&current->sighand->siglock);
1002         /*
1003          * This keeps any tasks waiting on the spin lock from thinking
1004          * they got something (see the lock code above).
1005          */
1006         timer->it_signal = NULL;
1007 
1008         unlock_timer(timer, flags);
1009         release_posix_timer(timer, IT_ID_SET);
1010         return 0;
1011 }
1012 
1013 /*
1014  * return timer owned by the process, used by exit_itimers
1015  */
1016 static void itimer_delete(struct k_itimer *timer)
1017 {
1018 retry_delete:
1019         spin_lock_irq(&timer->it_lock);
1020 
1021         if (timer_delete_hook(timer) == TIMER_RETRY) {
1022                 spin_unlock_irq(&timer->it_lock);
1023                 goto retry_delete;
1024         }
1025         list_del(&timer->list);
1026 
1027         spin_unlock_irq(&timer->it_lock);
1028         release_posix_timer(timer, IT_ID_SET);
1029 }
1030 
1031 /*
1032  * This is called by do_exit or de_thread, only when there are no more
1033  * references to the shared signal_struct.
1034  */
1035 void exit_itimers(struct signal_struct *sig)
1036 {
1037         struct k_itimer *tmr;
1038 
1039         while (!list_empty(&sig->posix_timers)) {
1040                 tmr = list_entry(sig->posix_timers.next, struct k_itimer, list);
1041                 itimer_delete(tmr);
1042         }
1043 }
1044 
1045 SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock,
1046                 const struct __kernel_timespec __user *, tp)
1047 {
1048         const struct k_clock *kc = clockid_to_kclock(which_clock);
1049         struct timespec64 new_tp;
1050 
1051         if (!kc || !kc->clock_set)
1052                 return -EINVAL;
1053 
1054         if (get_timespec64(&new_tp, tp))
1055                 return -EFAULT;
1056 
1057         return kc->clock_set(which_clock, &new_tp);
1058 }
1059 
1060 SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock,
1061                 struct __kernel_timespec __user *, tp)
1062 {
1063         const struct k_clock *kc = clockid_to_kclock(which_clock);
1064         struct timespec64 kernel_tp;
1065         int error;
1066 
1067         if (!kc)
1068                 return -EINVAL;
1069 
1070         error = kc->clock_get(which_clock, &kernel_tp);
1071 
1072         if (!error && put_timespec64(&kernel_tp, tp))
1073                 error = -EFAULT;
1074 
1075         return error;
1076 }
1077 
1078 int do_clock_adjtime(const clockid_t which_clock, struct __kernel_timex * ktx)
1079 {
1080         const struct k_clock *kc = clockid_to_kclock(which_clock);
1081 
1082         if (!kc)
1083                 return -EINVAL;
1084         if (!kc->clock_adj)
1085                 return -EOPNOTSUPP;
1086 
1087         return kc->clock_adj(which_clock, ktx);
1088 }
1089 
1090 SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
1091                 struct __kernel_timex __user *, utx)
1092 {
1093         struct __kernel_timex ktx;
1094         int err;
1095 
1096         if (copy_from_user(&ktx, utx, sizeof(ktx)))
1097                 return -EFAULT;
1098 
1099         err = do_clock_adjtime(which_clock, &ktx);
1100 
1101         if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
1102                 return -EFAULT;
1103 
1104         return err;
1105 }
1106 
1107 SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,
1108                 struct __kernel_timespec __user *, tp)
1109 {
1110         const struct k_clock *kc = clockid_to_kclock(which_clock);
1111         struct timespec64 rtn_tp;
1112         int error;
1113 
1114         if (!kc)
1115                 return -EINVAL;
1116 
1117         error = kc->clock_getres(which_clock, &rtn_tp);
1118 
1119         if (!error && tp && put_timespec64(&rtn_tp, tp))
1120                 error = -EFAULT;
1121 
1122         return error;
1123 }
1124 
1125 #ifdef CONFIG_COMPAT_32BIT_TIME
1126 
1127 SYSCALL_DEFINE2(clock_settime32, clockid_t, which_clock,
1128                 struct old_timespec32 __user *, tp)
1129 {
1130         const struct k_clock *kc = clockid_to_kclock(which_clock);
1131         struct timespec64 ts;
1132 
1133         if (!kc || !kc->clock_set)
1134                 return -EINVAL;
1135 
1136         if (get_old_timespec32(&ts, tp))
1137                 return -EFAULT;
1138 
1139         return kc->clock_set(which_clock, &ts);
1140 }
1141 
1142 SYSCALL_DEFINE2(clock_gettime32, clockid_t, which_clock,
1143                 struct old_timespec32 __user *, tp)
1144 {
1145         const struct k_clock *kc = clockid_to_kclock(which_clock);
1146         struct timespec64 ts;
1147         int err;
1148 
1149         if (!kc)
1150                 return -EINVAL;
1151 
1152         err = kc->clock_get(which_clock, &ts);
1153 
1154         if (!err && put_old_timespec32(&ts, tp))
1155                 err = -EFAULT;
1156 
1157         return err;
1158 }
1159 
1160 SYSCALL_DEFINE2(clock_adjtime32, clockid_t, which_clock,
1161                 struct old_timex32 __user *, utp)
1162 {
1163         struct __kernel_timex ktx;
1164         int err;
1165 
1166         err = get_old_timex32(&ktx, utp);
1167         if (err)
1168                 return err;
1169 
1170         err = do_clock_adjtime(which_clock, &ktx);
1171 
1172         if (err >= 0)
1173                 err = put_old_timex32(utp, &ktx);
1174 
1175         return err;
1176 }
1177 
1178 SYSCALL_DEFINE2(clock_getres_time32, clockid_t, which_clock,
1179                 struct old_timespec32 __user *, tp)
1180 {
1181         const struct k_clock *kc = clockid_to_kclock(which_clock);
1182         struct timespec64 ts;
1183         int err;
1184 
1185         if (!kc)
1186                 return -EINVAL;
1187 
1188         err = kc->clock_getres(which_clock, &ts);
1189         if (!err && tp && put_old_timespec32(&ts, tp))
1190                 return -EFAULT;
1191 
1192         return err;
1193 }
1194 
1195 #endif
1196 
1197 /*
1198  * nanosleep for monotonic and realtime clocks
1199  */
1200 static int common_nsleep(const clockid_t which_clock, int flags,
1201                          const struct timespec64 *rqtp)
1202 {
1203         return hrtimer_nanosleep(rqtp, flags & TIMER_ABSTIME ?
1204                                  HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
1205                                  which_clock);
1206 }
1207 
1208 SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
1209                 const struct __kernel_timespec __user *, rqtp,
1210                 struct __kernel_timespec __user *, rmtp)
1211 {
1212         const struct k_clock *kc = clockid_to_kclock(which_clock);
1213         struct timespec64 t;
1214 
1215         if (!kc)
1216                 return -EINVAL;
1217         if (!kc->nsleep)
1218                 return -EOPNOTSUPP;
1219 
1220         if (get_timespec64(&t, rqtp))
1221                 return -EFAULT;
1222 
1223         if (!timespec64_valid(&t))
1224                 return -EINVAL;
1225         if (flags & TIMER_ABSTIME)
1226                 rmtp = NULL;
1227         current->restart_block.nanosleep.type = rmtp ? TT_NATIVE : TT_NONE;
1228         current->restart_block.nanosleep.rmtp = rmtp;
1229 
1230         return kc->nsleep(which_clock, flags, &t);
1231 }
1232 
1233 #ifdef CONFIG_COMPAT_32BIT_TIME
1234 
1235 SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags,
1236                 struct old_timespec32 __user *, rqtp,
1237                 struct old_timespec32 __user *, rmtp)
1238 {
1239         const struct k_clock *kc = clockid_to_kclock(which_clock);
1240         struct timespec64 t;
1241 
1242         if (!kc)
1243                 return -EINVAL;
1244         if (!kc->nsleep)
1245                 return -EOPNOTSUPP;
1246 
1247         if (get_old_timespec32(&t, rqtp))
1248                 return -EFAULT;
1249 
1250         if (!timespec64_valid(&t))
1251                 return -EINVAL;
1252         if (flags & TIMER_ABSTIME)
1253                 rmtp = NULL;
1254         current->restart_block.nanosleep.type = rmtp ? TT_COMPAT : TT_NONE;
1255         current->restart_block.nanosleep.compat_rmtp = rmtp;
1256 
1257         return kc->nsleep(which_clock, flags, &t);
1258 }
1259 
1260 #endif
1261 
1262 static const struct k_clock clock_realtime = {
1263         .clock_getres           = posix_get_hrtimer_res,
1264         .clock_get              = posix_clock_realtime_get,
1265         .clock_set              = posix_clock_realtime_set,
1266         .clock_adj              = posix_clock_realtime_adj,
1267         .nsleep                 = common_nsleep,
1268         .timer_create           = common_timer_create,
1269         .timer_set              = common_timer_set,
1270         .timer_get              = common_timer_get,
1271         .timer_del              = common_timer_del,
1272         .timer_rearm            = common_hrtimer_rearm,
1273         .timer_forward          = common_hrtimer_forward,
1274         .timer_remaining        = common_hrtimer_remaining,
1275         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1276         .timer_wait_running     = common_timer_wait_running,
1277         .timer_arm              = common_hrtimer_arm,
1278 };
1279 
1280 static const struct k_clock clock_monotonic = {
1281         .clock_getres           = posix_get_hrtimer_res,
1282         .clock_get              = posix_ktime_get_ts,
1283         .nsleep                 = common_nsleep,
1284         .timer_create           = common_timer_create,
1285         .timer_set              = common_timer_set,
1286         .timer_get              = common_timer_get,
1287         .timer_del              = common_timer_del,
1288         .timer_rearm            = common_hrtimer_rearm,
1289         .timer_forward          = common_hrtimer_forward,
1290         .timer_remaining        = common_hrtimer_remaining,
1291         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1292         .timer_wait_running     = common_timer_wait_running,
1293         .timer_arm              = common_hrtimer_arm,
1294 };
1295 
1296 static const struct k_clock clock_monotonic_raw = {
1297         .clock_getres           = posix_get_hrtimer_res,
1298         .clock_get              = posix_get_monotonic_raw,
1299 };
1300 
1301 static const struct k_clock clock_realtime_coarse = {
1302         .clock_getres           = posix_get_coarse_res,
1303         .clock_get              = posix_get_realtime_coarse,
1304 };
1305 
1306 static const struct k_clock clock_monotonic_coarse = {
1307         .clock_getres           = posix_get_coarse_res,
1308         .clock_get              = posix_get_monotonic_coarse,
1309 };
1310 
1311 static const struct k_clock clock_tai = {
1312         .clock_getres           = posix_get_hrtimer_res,
1313         .clock_get              = posix_get_tai,
1314         .nsleep                 = common_nsleep,
1315         .timer_create           = common_timer_create,
1316         .timer_set              = common_timer_set,
1317         .timer_get              = common_timer_get,
1318         .timer_del              = common_timer_del,
1319         .timer_rearm            = common_hrtimer_rearm,
1320         .timer_forward          = common_hrtimer_forward,
1321         .timer_remaining        = common_hrtimer_remaining,
1322         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1323         .timer_wait_running     = common_timer_wait_running,
1324         .timer_arm              = common_hrtimer_arm,
1325 };
1326 
1327 static const struct k_clock clock_boottime = {
1328         .clock_getres           = posix_get_hrtimer_res,
1329         .clock_get              = posix_get_boottime,
1330         .nsleep                 = common_nsleep,
1331         .timer_create           = common_timer_create,
1332         .timer_set              = common_timer_set,
1333         .timer_get              = common_timer_get,
1334         .timer_del              = common_timer_del,
1335         .timer_rearm            = common_hrtimer_rearm,
1336         .timer_forward          = common_hrtimer_forward,
1337         .timer_remaining        = common_hrtimer_remaining,
1338         .timer_try_to_cancel    = common_hrtimer_try_to_cancel,
1339         .timer_wait_running     = common_timer_wait_running,
1340         .timer_arm              = common_hrtimer_arm,
1341 };
1342 
1343 static const struct k_clock * const posix_clocks[] = {
1344         [CLOCK_REALTIME]                = &clock_realtime,
1345         [CLOCK_MONOTONIC]               = &clock_monotonic,
1346         [CLOCK_PROCESS_CPUTIME_ID]      = &clock_process,
1347         [CLOCK_THREAD_CPUTIME_ID]       = &clock_thread,
1348         [CLOCK_MONOTONIC_RAW]           = &clock_monotonic_raw,
1349         [CLOCK_REALTIME_COARSE]         = &clock_realtime_coarse,
1350         [CLOCK_MONOTONIC_COARSE]        = &clock_monotonic_coarse,
1351         [CLOCK_BOOTTIME]                = &clock_boottime,
1352         [CLOCK_REALTIME_ALARM]          = &alarm_clock,
1353         [CLOCK_BOOTTIME_ALARM]          = &alarm_clock,
1354         [CLOCK_TAI]                     = &clock_tai,
1355 };
1356 
1357 static const struct k_clock *clockid_to_kclock(const clockid_t id)
1358 {
1359         clockid_t idx = id;
1360 
1361         if (id < 0) {
1362                 return (id & CLOCKFD_MASK) == CLOCKFD ?
1363                         &clock_posix_dynamic : &clock_posix_cpu;
1364         }
1365 
1366         if (id >= ARRAY_SIZE(posix_clocks))
1367                 return NULL;
1368 
1369         return posix_clocks[array_index_nospec(idx, ARRAY_SIZE(posix_clocks))];
1370 }
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root/kernel/time/posix-timers.c

DEFINITIONS
