/* $NetBSD: kern_time.c,v 1.197.4.4 2020/11/01 17:26:01 martin Exp $ */ /*- * Copyright (c) 2000, 2004, 2005, 2007, 2008, 2009 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Christopher G. Demetriou, and by Andrew Doran. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)kern_time.c 8.4 (Berkeley) 5/26/95 */ #include __KERNEL_RCSID(0, "$NetBSD: kern_time.c,v 1.197.4.4 2020/11/01 17:26:01 martin Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include static void timer_intr(void *); static void itimerfire(struct ptimer *); static void itimerfree(struct ptimers *, int); kmutex_t timer_lock; static void *timer_sih; static TAILQ_HEAD(, ptimer) timer_queue; struct pool ptimer_pool, ptimers_pool; #define CLOCK_VIRTUAL_P(clockid) \ ((clockid) == CLOCK_VIRTUAL || (clockid) == CLOCK_PROF) CTASSERT(ITIMER_REAL == CLOCK_REALTIME); CTASSERT(ITIMER_VIRTUAL == CLOCK_VIRTUAL); CTASSERT(ITIMER_PROF == CLOCK_PROF); CTASSERT(ITIMER_MONOTONIC == CLOCK_MONOTONIC); #define DELAYTIMER_MAX 32 /* * Initialize timekeeping. */ void time_init(void) { pool_init(&ptimer_pool, sizeof(struct ptimer), 0, 0, 0, "ptimerpl", &pool_allocator_nointr, IPL_NONE); pool_init(&ptimers_pool, sizeof(struct ptimers), 0, 0, 0, "ptimerspl", &pool_allocator_nointr, IPL_NONE); } void time_init2(void) { TAILQ_INIT(&timer_queue); mutex_init(&timer_lock, MUTEX_DEFAULT, IPL_SCHED); timer_sih = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE, timer_intr, NULL); } /* Time of day and interval timer support. * * These routines provide the kernel entry points to get and set * the time-of-day and per-process interval timers. Subroutines * here provide support for adding and subtracting timeval structures * and decrementing interval timers, optionally reloading the interval * timers when they expire. */ /* This function is used by clock_settime and settimeofday */ static int settime1(struct proc *p, const struct timespec *ts, bool check_kauth) { struct timespec delta, now; int s; /* * The time being set to an unreasonable value will cause * unreasonable system behaviour. */ if (ts->tv_sec < 0 || ts->tv_sec > (1LL << 36)) return (EINVAL); /* WHAT DO WE DO ABOUT PENDING REAL-TIME TIMEOUTS??? */ s = splclock(); nanotime(&now); timespecsub(ts, &now, &delta); if (check_kauth && kauth_authorize_system(kauth_cred_get(), KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_SYSTEM, __UNCONST(ts), &delta, KAUTH_ARG(check_kauth ? false : true)) != 0) { splx(s); return (EPERM); } #ifdef notyet if ((delta.tv_sec < 86400) && securelevel > 0) { /* XXX elad - notyet */ splx(s); return (EPERM); } #endif tc_setclock(ts); timespecadd(&boottime, &delta, &boottime); resettodr(); splx(s); return (0); } int settime(struct proc *p, struct timespec *ts) { return (settime1(p, ts, true)); } /* ARGSUSED */ int sys___clock_gettime50(struct lwp *l, const struct sys___clock_gettime50_args *uap, register_t *retval) { /* { syscallarg(clockid_t) clock_id; syscallarg(struct timespec *) tp; } */ int error; struct timespec ats; error = clock_gettime1(SCARG(uap, clock_id), &ats); if (error != 0) return error; return copyout(&ats, SCARG(uap, tp), sizeof(ats)); } /* ARGSUSED */ int sys___clock_settime50(struct lwp *l, const struct sys___clock_settime50_args *uap, register_t *retval) { /* { syscallarg(clockid_t) clock_id; syscallarg(const struct timespec *) tp; } */ int error; struct timespec ats; if ((error = copyin(SCARG(uap, tp), &ats, sizeof(ats))) != 0) return error; return clock_settime1(l->l_proc, SCARG(uap, clock_id), &ats, true); } int clock_settime1(struct proc *p, clockid_t clock_id, const struct timespec *tp, bool check_kauth) { int error; switch (clock_id) { case CLOCK_REALTIME: if ((error = settime1(p, tp, check_kauth)) != 0) return (error); break; case CLOCK_MONOTONIC: return (EINVAL); /* read-only clock */ default: return (EINVAL); } return 0; } int sys___clock_getres50(struct lwp *l, const struct sys___clock_getres50_args *uap, register_t *retval) { /* { syscallarg(clockid_t) clock_id; syscallarg(struct timespec *) tp; } */ struct timespec ts; int error; if ((error = clock_getres1(SCARG(uap, clock_id), &ts)) != 0) return error; if (SCARG(uap, tp)) error = copyout(&ts, SCARG(uap, tp), sizeof(ts)); return error; } int clock_getres1(clockid_t clock_id, struct timespec *ts) { switch (clock_id) { case CLOCK_REALTIME: case CLOCK_MONOTONIC: ts->tv_sec = 0; if (tc_getfrequency() > 1000000000) ts->tv_nsec = 1; else ts->tv_nsec = 1000000000 / tc_getfrequency(); break; default: return EINVAL; } return 0; } /* ARGSUSED */ int sys___nanosleep50(struct lwp *l, const struct sys___nanosleep50_args *uap, register_t *retval) { /* { syscallarg(struct timespec *) rqtp; syscallarg(struct timespec *) rmtp; } */ struct timespec rmt, rqt; int error, error1; error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec)); if (error) return (error); error = nanosleep1(l, CLOCK_MONOTONIC, 0, &rqt, SCARG(uap, rmtp) ? &rmt : NULL); if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR)) return error; error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt)); return error1 ? error1 : error; } /* ARGSUSED */ int sys_clock_nanosleep(struct lwp *l, const struct sys_clock_nanosleep_args *uap, register_t *retval) { /* { syscallarg(clockid_t) clock_id; syscallarg(int) flags; syscallarg(struct timespec *) rqtp; syscallarg(struct timespec *) rmtp; } */ struct timespec rmt, rqt; int error, error1; error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec)); if (error) goto out; error = nanosleep1(l, SCARG(uap, clock_id), SCARG(uap, flags), &rqt, SCARG(uap, rmtp) ? &rmt : NULL); if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR)) goto out; if ((SCARG(uap, flags) & TIMER_ABSTIME) == 0 && (error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt))) != 0) error = error1; out: *retval = error; return 0; } int nanosleep1(struct lwp *l, clockid_t clock_id, int flags, struct timespec *rqt, struct timespec *rmt) { struct timespec rmtstart; int error, timo; if ((error = ts2timo(clock_id, flags, rqt, &timo, &rmtstart)) != 0) { if (error == ETIMEDOUT) { error = 0; if (rmt != NULL) rmt->tv_sec = rmt->tv_nsec = 0; } return error; } /* * Avoid inadvertently sleeping forever */ if (timo == 0) timo = 1; again: error = kpause("nanoslp", true, timo, NULL); if (error == EWOULDBLOCK) error = 0; if (rmt != NULL || error == 0) { struct timespec rmtend; struct timespec t0; struct timespec *t; int err; err = clock_gettime1(clock_id, &rmtend); if (err != 0) return err; t = (rmt != NULL) ? rmt : &t0; if (flags & TIMER_ABSTIME) { timespecsub(rqt, &rmtend, t); } else { timespecsub(&rmtend, &rmtstart, t); timespecsub(rqt, t, t); } if (t->tv_sec < 0) timespecclear(t); if (error == 0) { timo = tstohz(t); if (timo > 0) goto again; } } if (error == ERESTART) error = EINTR; return error; } int sys_clock_getcpuclockid2(struct lwp *l, const struct sys_clock_getcpuclockid2_args *uap, register_t *retval) { /* { syscallarg(idtype_t idtype; syscallarg(id_t id); syscallarg(clockid_t *)clock_id; } */ pid_t pid; lwpid_t lid; clockid_t clock_id; id_t id = SCARG(uap, id); switch (SCARG(uap, idtype)) { case P_PID: pid = id == 0 ? l->l_proc->p_pid : id; clock_id = CLOCK_PROCESS_CPUTIME_ID | pid; break; case P_LWPID: lid = id == 0 ? l->l_lid : id; clock_id = CLOCK_THREAD_CPUTIME_ID | lid; break; default: return EINVAL; } return copyout(&clock_id, SCARG(uap, clock_id), sizeof(clock_id)); } /* ARGSUSED */ int sys___gettimeofday50(struct lwp *l, const struct sys___gettimeofday50_args *uap, register_t *retval) { /* { syscallarg(struct timeval *) tp; syscallarg(void *) tzp; really "struct timezone *"; } */ struct timeval atv; int error = 0; struct timezone tzfake; if (SCARG(uap, tp)) { memset(&atv, 0, sizeof(atv)); microtime(&atv); error = copyout(&atv, SCARG(uap, tp), sizeof(atv)); if (error) return (error); } if (SCARG(uap, tzp)) { /* * NetBSD has no kernel notion of time zone, so we just * fake up a timezone struct and return it if demanded. */ tzfake.tz_minuteswest = 0; tzfake.tz_dsttime = 0; error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake)); } return (error); } /* ARGSUSED */ int sys___settimeofday50(struct lwp *l, const struct sys___settimeofday50_args *uap, register_t *retval) { /* { syscallarg(const struct timeval *) tv; syscallarg(const void *) tzp; really "const struct timezone *"; } */ return settimeofday1(SCARG(uap, tv), true, SCARG(uap, tzp), l, true); } int settimeofday1(const struct timeval *utv, bool userspace, const void *utzp, struct lwp *l, bool check_kauth) { struct timeval atv; struct timespec ts; int error; /* Verify all parameters before changing time. */ /* * NetBSD has no kernel notion of time zone, and only an * obsolete program would try to set it, so we log a warning. */ if (utzp) log(LOG_WARNING, "pid %d attempted to set the " "(obsolete) kernel time zone\n", l->l_proc->p_pid); if (utv == NULL) return 0; if (userspace) { if ((error = copyin(utv, &atv, sizeof(atv))) != 0) return error; utv = &atv; } TIMEVAL_TO_TIMESPEC(utv, &ts); return settime1(l->l_proc, &ts, check_kauth); } int time_adjusted; /* set if an adjustment is made */ /* ARGSUSED */ int sys___adjtime50(struct lwp *l, const struct sys___adjtime50_args *uap, register_t *retval) { /* { syscallarg(const struct timeval *) delta; syscallarg(struct timeval *) olddelta; } */ int error; struct timeval atv, oldatv; if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_ADJTIME, NULL, NULL, NULL)) != 0) return error; if (SCARG(uap, delta)) { error = copyin(SCARG(uap, delta), &atv, sizeof(*SCARG(uap, delta))); if (error) return (error); } adjtime1(SCARG(uap, delta) ? &atv : NULL, SCARG(uap, olddelta) ? &oldatv : NULL, l->l_proc); if (SCARG(uap, olddelta)) error = copyout(&oldatv, SCARG(uap, olddelta), sizeof(*SCARG(uap, olddelta))); return error; } void adjtime1(const struct timeval *delta, struct timeval *olddelta, struct proc *p) { extern int64_t time_adjtime; /* in kern_ntptime.c */ if (olddelta) { memset(olddelta, 0, sizeof(*olddelta)); mutex_spin_enter(&timecounter_lock); olddelta->tv_sec = time_adjtime / 1000000; olddelta->tv_usec = time_adjtime % 1000000; if (olddelta->tv_usec < 0) { olddelta->tv_usec += 1000000; olddelta->tv_sec--; } mutex_spin_exit(&timecounter_lock); } if (delta) { mutex_spin_enter(&timecounter_lock); time_adjtime = delta->tv_sec * 1000000 + delta->tv_usec; if (time_adjtime) { /* We need to save the system time during shutdown */ time_adjusted |= 1; } mutex_spin_exit(&timecounter_lock); } } /* * Interval timer support. Both the BSD getitimer() family and the POSIX * timer_*() family of routines are supported. * * All timers are kept in an array pointed to by p_timers, which is * allocated on demand - many processes don't use timers at all. The * first four elements in this array are reserved for the BSD timers: * element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, element * 2 is ITIMER_PROF, and element 3 is ITIMER_MONOTONIC. The rest may be * allocated by the timer_create() syscall. * * Realtime timers are kept in the ptimer structure as an absolute * time; virtual time timers are kept as a linked list of deltas. * Virtual time timers are processed in the hardclock() routine of * kern_clock.c. The real time timer is processed by a callout * routine, called from the softclock() routine. Since a callout may * be delayed in real time due to interrupt processing in the system, * it is possible for the real time timeout routine (realtimeexpire, * given below), to be delayed in real time past when it is supposed * to occur. It does not suffice, therefore, to reload the real timer * .it_value from the real time timers .it_interval. Rather, we * compute the next time in absolute time the timer should go off. */ /* Allocate a POSIX realtime timer. */ int sys_timer_create(struct lwp *l, const struct sys_timer_create_args *uap, register_t *retval) { /* { syscallarg(clockid_t) clock_id; syscallarg(struct sigevent *) evp; syscallarg(timer_t *) timerid; } */ return timer_create1(SCARG(uap, timerid), SCARG(uap, clock_id), SCARG(uap, evp), copyin, l); } int timer_create1(timer_t *tid, clockid_t id, struct sigevent *evp, copyin_t fetch_event, struct lwp *l) { int error; timer_t timerid; struct ptimers *pts; struct ptimer *pt; struct proc *p; p = l->l_proc; if ((u_int)id > CLOCK_MONOTONIC) return (EINVAL); if ((pts = p->p_timers) == NULL) pts = timers_alloc(p); pt = pool_get(&ptimer_pool, PR_WAITOK | PR_ZERO); if (evp != NULL) { if (((error = (*fetch_event)(evp, &pt->pt_ev, sizeof(pt->pt_ev))) != 0) || ((pt->pt_ev.sigev_notify < SIGEV_NONE) || (pt->pt_ev.sigev_notify > SIGEV_SA)) || (pt->pt_ev.sigev_notify == SIGEV_SIGNAL && (pt->pt_ev.sigev_signo <= 0 || pt->pt_ev.sigev_signo >= NSIG))) { pool_put(&ptimer_pool, pt); return (error ? error : EINVAL); } } /* Find a free timer slot, skipping those reserved for setitimer(). */ mutex_spin_enter(&timer_lock); for (timerid = TIMER_MIN; timerid < TIMER_MAX; timerid++) if (pts->pts_timers[timerid] == NULL) break; if (timerid == TIMER_MAX) { mutex_spin_exit(&timer_lock); pool_put(&ptimer_pool, pt); return EAGAIN; } if (evp == NULL) { pt->pt_ev.sigev_notify = SIGEV_SIGNAL; switch (id) { case CLOCK_REALTIME: case CLOCK_MONOTONIC: pt->pt_ev.sigev_signo = SIGALRM; break; case CLOCK_VIRTUAL: pt->pt_ev.sigev_signo = SIGVTALRM; break; case CLOCK_PROF: pt->pt_ev.sigev_signo = SIGPROF; break; } pt->pt_ev.sigev_value.sival_int = timerid; } pt->pt_info.ksi_signo = pt->pt_ev.sigev_signo; pt->pt_info.ksi_errno = 0; pt->pt_info.ksi_code = 0; pt->pt_info.ksi_pid = p->p_pid; pt->pt_info.ksi_uid = kauth_cred_getuid(l->l_cred); pt->pt_info.ksi_value = pt->pt_ev.sigev_value; pt->pt_type = id; pt->pt_proc = p; pt->pt_overruns = 0; pt->pt_poverruns = 0; pt->pt_entry = timerid; pt->pt_queued = false; timespecclear(&pt->pt_time.it_value); if (!CLOCK_VIRTUAL_P(id)) callout_init(&pt->pt_ch, CALLOUT_MPSAFE); else pt->pt_active = 0; pts->pts_timers[timerid] = pt; mutex_spin_exit(&timer_lock); return copyout(&timerid, tid, sizeof(timerid)); } /* Delete a POSIX realtime timer */ int sys_timer_delete(struct lwp *l, const struct sys_timer_delete_args *uap, register_t *retval) { /* { syscallarg(timer_t) timerid; } */ struct proc *p = l->l_proc; timer_t timerid; struct ptimers *pts; struct ptimer *pt, *ptn; timerid = SCARG(uap, timerid); pts = p->p_timers; if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) return (EINVAL); mutex_spin_enter(&timer_lock); if ((pt = pts->pts_timers[timerid]) == NULL) { mutex_spin_exit(&timer_lock); return (EINVAL); } if (CLOCK_VIRTUAL_P(pt->pt_type)) { if (pt->pt_active) { ptn = LIST_NEXT(pt, pt_list); LIST_REMOVE(pt, pt_list); for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list)) timespecadd(&pt->pt_time.it_value, &ptn->pt_time.it_value, &ptn->pt_time.it_value); pt->pt_active = 0; } } /* Free the timer and release the lock. */ itimerfree(pts, timerid); return (0); } /* * Set up the given timer. The value in pt->pt_time.it_value is taken * to be an absolute time for CLOCK_REALTIME/CLOCK_MONOTONIC timers and * a relative time for CLOCK_VIRTUAL/CLOCK_PROF timers. * * If the callout had already fired but not yet run, fails with * ERESTART -- caller must restart from the top to look up a timer. */ int timer_settime(struct ptimer *pt) { struct ptimer *ptn, *pptn; struct ptlist *ptl; KASSERT(mutex_owned(&timer_lock)); if (!CLOCK_VIRTUAL_P(pt->pt_type)) { /* * Try to stop the callout. However, if it had already * fired, we have to drop the lock to wait for it, so * the world may have changed and pt may not be there * any more. In that case, tell the caller to start * over from the top. */ if (callout_halt(&pt->pt_ch, &timer_lock)) return ERESTART; /* Now we can touch pt and start it up again. */ if (timespecisset(&pt->pt_time.it_value)) { /* * Don't need to check tshzto() return value, here. * callout_reset() does it for us. */ callout_reset(&pt->pt_ch, pt->pt_type == CLOCK_MONOTONIC ? tshztoup(&pt->pt_time.it_value) : tshzto(&pt->pt_time.it_value), realtimerexpire, pt); } } else { if (pt->pt_active) { ptn = LIST_NEXT(pt, pt_list); LIST_REMOVE(pt, pt_list); for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list)) timespecadd(&pt->pt_time.it_value, &ptn->pt_time.it_value, &ptn->pt_time.it_value); } if (timespecisset(&pt->pt_time.it_value)) { if (pt->pt_type == CLOCK_VIRTUAL) ptl = &pt->pt_proc->p_timers->pts_virtual; else ptl = &pt->pt_proc->p_timers->pts_prof; for (ptn = LIST_FIRST(ptl), pptn = NULL; ptn && timespeccmp(&pt->pt_time.it_value, &ptn->pt_time.it_value, >); pptn = ptn, ptn = LIST_NEXT(ptn, pt_list)) timespecsub(&pt->pt_time.it_value, &ptn->pt_time.it_value, &pt->pt_time.it_value); if (pptn) LIST_INSERT_AFTER(pptn, pt, pt_list); else LIST_INSERT_HEAD(ptl, pt, pt_list); for ( ; ptn ; ptn = LIST_NEXT(ptn, pt_list)) timespecsub(&ptn->pt_time.it_value, &pt->pt_time.it_value, &ptn->pt_time.it_value); pt->pt_active = 1; } else pt->pt_active = 0; } /* Success! */ return 0; } void timer_gettime(struct ptimer *pt, struct itimerspec *aits) { struct timespec now; struct ptimer *ptn; KASSERT(mutex_owned(&timer_lock)); *aits = pt->pt_time; if (!CLOCK_VIRTUAL_P(pt->pt_type)) { /* * Convert from absolute to relative time in .it_value * part of real time timer. If time for real time * timer has passed return 0, else return difference * between current time and time for the timer to go * off. */ if (timespecisset(&aits->it_value)) { if (pt->pt_type == CLOCK_REALTIME) { getnanotime(&now); } else { /* CLOCK_MONOTONIC */ getnanouptime(&now); } if (timespeccmp(&aits->it_value, &now, <)) timespecclear(&aits->it_value); else timespecsub(&aits->it_value, &now, &aits->it_value); } } else if (pt->pt_active) { if (pt->pt_type == CLOCK_VIRTUAL) ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_virtual); else ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_prof); for ( ; ptn && ptn != pt; ptn = LIST_NEXT(ptn, pt_list)) timespecadd(&aits->it_value, &ptn->pt_time.it_value, &aits->it_value); KASSERT(ptn != NULL); /* pt should be findable on the list */ } else timespecclear(&aits->it_value); } /* Set and arm a POSIX realtime timer */ int sys___timer_settime50(struct lwp *l, const struct sys___timer_settime50_args *uap, register_t *retval) { /* { syscallarg(timer_t) timerid; syscallarg(int) flags; syscallarg(const struct itimerspec *) value; syscallarg(struct itimerspec *) ovalue; } */ int error; struct itimerspec value, ovalue, *ovp = NULL; if ((error = copyin(SCARG(uap, value), &value, sizeof(struct itimerspec))) != 0) return (error); if (SCARG(uap, ovalue)) ovp = &ovalue; if ((error = dotimer_settime(SCARG(uap, timerid), &value, ovp, SCARG(uap, flags), l->l_proc)) != 0) return error; if (ovp) return copyout(&ovalue, SCARG(uap, ovalue), sizeof(struct itimerspec)); return 0; } int dotimer_settime(int timerid, struct itimerspec *value, struct itimerspec *ovalue, int flags, struct proc *p) { struct timespec now; struct itimerspec val, oval; struct ptimers *pts; struct ptimer *pt; int error; pts = p->p_timers; if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) return EINVAL; val = *value; if ((error = itimespecfix(&val.it_value)) != 0 || (error = itimespecfix(&val.it_interval)) != 0) return error; mutex_spin_enter(&timer_lock); restart: if ((pt = pts->pts_timers[timerid]) == NULL) { mutex_spin_exit(&timer_lock); return EINVAL; } oval = pt->pt_time; pt->pt_time = val; /* * If we've been passed a relative time for a realtime timer, * convert it to absolute; if an absolute time for a virtual * timer, convert it to relative and make sure we don't set it * to zero, which would cancel the timer, or let it go * negative, which would confuse the comparison tests. */ if (timespecisset(&pt->pt_time.it_value)) { if (!CLOCK_VIRTUAL_P(pt->pt_type)) { if ((flags & TIMER_ABSTIME) == 0) { if (pt->pt_type == CLOCK_REALTIME) { getnanotime(&now); } else { /* CLOCK_MONOTONIC */ getnanouptime(&now); } timespecadd(&pt->pt_time.it_value, &now, &pt->pt_time.it_value); } } else { if ((flags & TIMER_ABSTIME) != 0) { getnanotime(&now); timespecsub(&pt->pt_time.it_value, &now, &pt->pt_time.it_value); if (!timespecisset(&pt->pt_time.it_value) || pt->pt_time.it_value.tv_sec < 0) { pt->pt_time.it_value.tv_sec = 0; pt->pt_time.it_value.tv_nsec = 1; } } } } error = timer_settime(pt); if (error == ERESTART) { KASSERT(!CLOCK_VIRTUAL_P(pt->pt_type)); goto restart; } KASSERT(error == 0); mutex_spin_exit(&timer_lock); if (ovalue) *ovalue = oval; return (0); } /* Return the time remaining until a POSIX timer fires. */ int sys___timer_gettime50(struct lwp *l, const struct sys___timer_gettime50_args *uap, register_t *retval) { /* { syscallarg(timer_t) timerid; syscallarg(struct itimerspec *) value; } */ struct itimerspec its; int error; if ((error = dotimer_gettime(SCARG(uap, timerid), l->l_proc, &its)) != 0) return error; return copyout(&its, SCARG(uap, value), sizeof(its)); } int dotimer_gettime(int timerid, struct proc *p, struct itimerspec *its) { struct ptimer *pt; struct ptimers *pts; pts = p->p_timers; if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) return (EINVAL); mutex_spin_enter(&timer_lock); if ((pt = pts->pts_timers[timerid]) == NULL) { mutex_spin_exit(&timer_lock); return (EINVAL); } timer_gettime(pt, its); mutex_spin_exit(&timer_lock); return 0; } /* * Return the count of the number of times a periodic timer expired * while a notification was already pending. The counter is reset when * a timer expires and a notification can be posted. */ int sys_timer_getoverrun(struct lwp *l, const struct sys_timer_getoverrun_args *uap, register_t *retval) { /* { syscallarg(timer_t) timerid; } */ struct proc *p = l->l_proc; struct ptimers *pts; int timerid; struct ptimer *pt; timerid = SCARG(uap, timerid); pts = p->p_timers; if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) return (EINVAL); mutex_spin_enter(&timer_lock); if ((pt = pts->pts_timers[timerid]) == NULL) { mutex_spin_exit(&timer_lock); return (EINVAL); } *retval = pt->pt_poverruns; if (*retval >= DELAYTIMER_MAX) *retval = DELAYTIMER_MAX; mutex_spin_exit(&timer_lock); return (0); } /* * Real interval timer expired: * send process whose timer expired an alarm signal. * If time is not set up to reload, then just return. * Else compute next time timer should go off which is > current time. * This is where delay in processing this timeout causes multiple * SIGALRM calls to be compressed into one. */ void realtimerexpire(void *arg) { uint64_t last_val, next_val, interval, now_ns; struct timespec now, next; struct ptimer *pt; int backwards; pt = arg; mutex_spin_enter(&timer_lock); itimerfire(pt); if (!timespecisset(&pt->pt_time.it_interval)) { timespecclear(&pt->pt_time.it_value); mutex_spin_exit(&timer_lock); return; } if (pt->pt_type == CLOCK_MONOTONIC) { getnanouptime(&now); } else { getnanotime(&now); } backwards = (timespeccmp(&pt->pt_time.it_value, &now, >)); timespecadd(&pt->pt_time.it_value, &pt->pt_time.it_interval, &next); /* Handle the easy case of non-overflown timers first. */ if (!backwards && timespeccmp(&next, &now, >)) { pt->pt_time.it_value = next; } else { now_ns = timespec2ns(&now); last_val = timespec2ns(&pt->pt_time.it_value); interval = timespec2ns(&pt->pt_time.it_interval); next_val = now_ns + (now_ns - last_val + interval - 1) % interval; if (backwards) next_val += interval; else pt->pt_overruns += (now_ns - last_val) / interval; pt->pt_time.it_value.tv_sec = next_val / 1000000000; pt->pt_time.it_value.tv_nsec = next_val % 1000000000; } /* * Reset the callout, if it's not going away. * * Don't need to check tshzto() return value, here. * callout_reset() does it for us. */ if (!pt->pt_dying) callout_reset(&pt->pt_ch, (pt->pt_type == CLOCK_MONOTONIC ? tshztoup(&pt->pt_time.it_value) : tshzto(&pt->pt_time.it_value)), realtimerexpire, pt); mutex_spin_exit(&timer_lock); } /* BSD routine to get the value of an interval timer. */ /* ARGSUSED */ int sys___getitimer50(struct lwp *l, const struct sys___getitimer50_args *uap, register_t *retval) { /* { syscallarg(int) which; syscallarg(struct itimerval *) itv; } */ struct proc *p = l->l_proc; struct itimerval aitv; int error; memset(&aitv, 0, sizeof(aitv)); error = dogetitimer(p, SCARG(uap, which), &aitv); if (error) return error; return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval))); } int dogetitimer(struct proc *p, int which, struct itimerval *itvp) { struct ptimers *pts; struct ptimer *pt; struct itimerspec its; if ((u_int)which > ITIMER_MONOTONIC) return (EINVAL); mutex_spin_enter(&timer_lock); pts = p->p_timers; if (pts == NULL || (pt = pts->pts_timers[which]) == NULL) { timerclear(&itvp->it_value); timerclear(&itvp->it_interval); } else { timer_gettime(pt, &its); TIMESPEC_TO_TIMEVAL(&itvp->it_value, &its.it_value); TIMESPEC_TO_TIMEVAL(&itvp->it_interval, &its.it_interval); } mutex_spin_exit(&timer_lock); return 0; } /* BSD routine to set/arm an interval timer. */ /* ARGSUSED */ int sys___setitimer50(struct lwp *l, const struct sys___setitimer50_args *uap, register_t *retval) { /* { syscallarg(int) which; syscallarg(const struct itimerval *) itv; syscallarg(struct itimerval *) oitv; } */ struct proc *p = l->l_proc; int which = SCARG(uap, which); struct sys___getitimer50_args getargs; const struct itimerval *itvp; struct itimerval aitv; int error; if ((u_int)which > ITIMER_MONOTONIC) return (EINVAL); itvp = SCARG(uap, itv); if (itvp && (error = copyin(itvp, &aitv, sizeof(struct itimerval))) != 0) return (error); if (SCARG(uap, oitv) != NULL) { SCARG(&getargs, which) = which; SCARG(&getargs, itv) = SCARG(uap, oitv); if ((error = sys___getitimer50(l, &getargs, retval)) != 0) return (error); } if (itvp == 0) return (0); return dosetitimer(p, which, &aitv); } int dosetitimer(struct proc *p, int which, struct itimerval *itvp) { struct timespec now; struct ptimers *pts; struct ptimer *pt, *spare; int error; KASSERT((u_int)which <= CLOCK_MONOTONIC); if (itimerfix(&itvp->it_value) || itimerfix(&itvp->it_interval)) return (EINVAL); /* * Don't bother allocating data structures if the process just * wants to clear the timer. */ spare = NULL; pts = p->p_timers; retry: if (!timerisset(&itvp->it_value) && (pts == NULL || pts->pts_timers[which] == NULL)) return (0); if (pts == NULL) pts = timers_alloc(p); mutex_spin_enter(&timer_lock); restart: pt = pts->pts_timers[which]; if (pt == NULL) { if (spare == NULL) { mutex_spin_exit(&timer_lock); spare = pool_get(&ptimer_pool, PR_WAITOK | PR_ZERO); goto retry; } pt = spare; spare = NULL; pt->pt_ev.sigev_notify = SIGEV_SIGNAL; pt->pt_ev.sigev_value.sival_int = which; pt->pt_overruns = 0; pt->pt_proc = p; pt->pt_type = which; pt->pt_entry = which; pt->pt_queued = false; if (!CLOCK_VIRTUAL_P(which)) callout_init(&pt->pt_ch, CALLOUT_MPSAFE); else pt->pt_active = 0; switch (which) { case ITIMER_REAL: case ITIMER_MONOTONIC: pt->pt_ev.sigev_signo = SIGALRM; break; case ITIMER_VIRTUAL: pt->pt_ev.sigev_signo = SIGVTALRM; break; case ITIMER_PROF: pt->pt_ev.sigev_signo = SIGPROF; break; } pts->pts_timers[which] = pt; } TIMEVAL_TO_TIMESPEC(&itvp->it_value, &pt->pt_time.it_value); TIMEVAL_TO_TIMESPEC(&itvp->it_interval, &pt->pt_time.it_interval); if (timespecisset(&pt->pt_time.it_value)) { /* Convert to absolute time */ /* XXX need to wrap in splclock for timecounters case? */ switch (which) { case ITIMER_REAL: getnanotime(&now); timespecadd(&pt->pt_time.it_value, &now, &pt->pt_time.it_value); break; case ITIMER_MONOTONIC: getnanouptime(&now); timespecadd(&pt->pt_time.it_value, &now, &pt->pt_time.it_value); break; default: break; } } error = timer_settime(pt); if (error == ERESTART) { KASSERT(!CLOCK_VIRTUAL_P(pt->pt_type)); goto restart; } KASSERT(error == 0); mutex_spin_exit(&timer_lock); if (spare != NULL) pool_put(&ptimer_pool, spare); return (0); } /* Utility routines to manage the array of pointers to timers. */ struct ptimers * timers_alloc(struct proc *p) { struct ptimers *pts; int i; pts = pool_get(&ptimers_pool, PR_WAITOK); LIST_INIT(&pts->pts_virtual); LIST_INIT(&pts->pts_prof); for (i = 0; i < TIMER_MAX; i++) pts->pts_timers[i] = NULL; mutex_spin_enter(&timer_lock); if (p->p_timers == NULL) { p->p_timers = pts; mutex_spin_exit(&timer_lock); return pts; } mutex_spin_exit(&timer_lock); pool_put(&ptimers_pool, pts); return p->p_timers; } /* * Clean up the per-process timers. If "which" is set to TIMERS_ALL, * then clean up all timers and free all the data structures. If * "which" is set to TIMERS_POSIX, only clean up the timers allocated * by timer_create(), not the BSD setitimer() timers, and only free the * structure if none of those remain. */ void timers_free(struct proc *p, int which) { struct ptimers *pts; struct ptimer *ptn; struct timespec ts; int i; if (p->p_timers == NULL) return; pts = p->p_timers; mutex_spin_enter(&timer_lock); if (which == TIMERS_ALL) { p->p_timers = NULL; i = 0; } else { timespecclear(&ts); for (ptn = LIST_FIRST(&pts->pts_virtual); ptn && ptn != pts->pts_timers[ITIMER_VIRTUAL]; ptn = LIST_NEXT(ptn, pt_list)) { KASSERT(ptn->pt_type == CLOCK_VIRTUAL); timespecadd(&ts, &ptn->pt_time.it_value, &ts); } LIST_FIRST(&pts->pts_virtual) = NULL; if (ptn) { KASSERT(ptn->pt_type == CLOCK_VIRTUAL); timespecadd(&ts, &ptn->pt_time.it_value, &ptn->pt_time.it_value); LIST_INSERT_HEAD(&pts->pts_virtual, ptn, pt_list); } timespecclear(&ts); for (ptn = LIST_FIRST(&pts->pts_prof); ptn && ptn != pts->pts_timers[ITIMER_PROF]; ptn = LIST_NEXT(ptn, pt_list)) { KASSERT(ptn->pt_type == CLOCK_PROF); timespecadd(&ts, &ptn->pt_time.it_value, &ts); } LIST_FIRST(&pts->pts_prof) = NULL; if (ptn) { KASSERT(ptn->pt_type == CLOCK_PROF); timespecadd(&ts, &ptn->pt_time.it_value, &ptn->pt_time.it_value); LIST_INSERT_HEAD(&pts->pts_prof, ptn, pt_list); } i = TIMER_MIN; } for ( ; i < TIMER_MAX; i++) { if (pts->pts_timers[i] != NULL) { /* Free the timer and release the lock. */ itimerfree(pts, i); /* Reacquire the lock for the next one. */ mutex_spin_enter(&timer_lock); } } if (pts->pts_timers[0] == NULL && pts->pts_timers[1] == NULL && pts->pts_timers[2] == NULL && pts->pts_timers[3] == NULL) { p->p_timers = NULL; mutex_spin_exit(&timer_lock); pool_put(&ptimers_pool, pts); } else mutex_spin_exit(&timer_lock); } static void itimerfree(struct ptimers *pts, int index) { struct ptimer *pt; KASSERT(mutex_owned(&timer_lock)); pt = pts->pts_timers[index]; /* * Prevent new references, and notify the callout not to * restart itself. */ pts->pts_timers[index] = NULL; pt->pt_dying = true; /* * For non-virtual timers, stop the callout, or wait for it to * run if it has already fired. It cannot restart again after * this point: the callout won't restart itself when dying, no * other users holding the lock can restart it, and any other * users waiting for callout_halt concurrently (timer_settime) * will restart from the top. */ if (!CLOCK_VIRTUAL_P(pt->pt_type)) callout_halt(&pt->pt_ch, &timer_lock); /* Remove it from the queue to be signalled. */ if (pt->pt_queued) TAILQ_REMOVE(&timer_queue, pt, pt_chain); /* All done with the global state. */ mutex_spin_exit(&timer_lock); /* Destroy the callout, if needed, and free the ptimer. */ if (!CLOCK_VIRTUAL_P(pt->pt_type)) callout_destroy(&pt->pt_ch); pool_put(&ptimer_pool, pt); } /* * Decrement an interval timer by a specified number * of nanoseconds, which must be less than a second, * i.e. < 1000000000. If the timer expires, then reload * it. In this case, carry over (nsec - old value) to * reduce the value reloaded into the timer so that * the timer does not drift. This routine assumes * that it is called in a context where the timers * on which it is operating cannot change in value. */ static int itimerdecr(struct ptimer *pt, int nsec) { struct itimerspec *itp; int error __diagused; KASSERT(mutex_owned(&timer_lock)); KASSERT(CLOCK_VIRTUAL_P(pt->pt_type)); itp = &pt->pt_time; if (itp->it_value.tv_nsec < nsec) { if (itp->it_value.tv_sec == 0) { /* expired, and already in next interval */ nsec -= itp->it_value.tv_nsec; goto expire; } itp->it_value.tv_nsec += 1000000000; itp->it_value.tv_sec--; } itp->it_value.tv_nsec -= nsec; nsec = 0; if (timespecisset(&itp->it_value)) return (1); /* expired, exactly at end of interval */ expire: if (timespecisset(&itp->it_interval)) { itp->it_value = itp->it_interval; itp->it_value.tv_nsec -= nsec; if (itp->it_value.tv_nsec < 0) { itp->it_value.tv_nsec += 1000000000; itp->it_value.tv_sec--; } error = timer_settime(pt); KASSERT(error == 0); /* virtual, never fails */ } else itp->it_value.tv_nsec = 0; /* sec is already 0 */ return (0); } static void itimerfire(struct ptimer *pt) { KASSERT(mutex_owned(&timer_lock)); /* * XXX Can overrun, but we don't do signal queueing yet, anyway. * XXX Relying on the clock interrupt is stupid. */ if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL || pt->pt_queued) { return; } TAILQ_INSERT_TAIL(&timer_queue, pt, pt_chain); pt->pt_queued = true; softint_schedule(timer_sih); } void timer_tick(lwp_t *l, bool user) { struct ptimers *pts; struct ptimer *pt; proc_t *p; p = l->l_proc; if (p->p_timers == NULL) return; mutex_spin_enter(&timer_lock); if ((pts = l->l_proc->p_timers) != NULL) { /* * Run current process's virtual and profile time, as needed. */ if (user && (pt = LIST_FIRST(&pts->pts_virtual)) != NULL) if (itimerdecr(pt, tick * 1000) == 0) itimerfire(pt); if ((pt = LIST_FIRST(&pts->pts_prof)) != NULL) if (itimerdecr(pt, tick * 1000) == 0) itimerfire(pt); } mutex_spin_exit(&timer_lock); } static void timer_intr(void *cookie) { ksiginfo_t ksi; struct ptimer *pt; proc_t *p; mutex_enter(proc_lock); mutex_spin_enter(&timer_lock); while ((pt = TAILQ_FIRST(&timer_queue)) != NULL) { TAILQ_REMOVE(&timer_queue, pt, pt_chain); KASSERT(pt->pt_queued); pt->pt_queued = false; if (pt->pt_proc->p_timers == NULL) { /* Process is dying. */ continue; } p = pt->pt_proc; if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL) { continue; } if (sigismember(&p->p_sigpend.sp_set, pt->pt_ev.sigev_signo)) { pt->pt_overruns++; continue; } KSI_INIT(&ksi); ksi.ksi_signo = pt->pt_ev.sigev_signo; ksi.ksi_code = SI_TIMER; ksi.ksi_value = pt->pt_ev.sigev_value; pt->pt_poverruns = pt->pt_overruns; pt->pt_overruns = 0; mutex_spin_exit(&timer_lock); kpsignal(p, &ksi, NULL); mutex_spin_enter(&timer_lock); } mutex_spin_exit(&timer_lock); mutex_exit(proc_lock); } /* * Check if the time will wrap if set to ts. * * ts - timespec describing the new time * delta - the delta between the current time and ts */ bool time_wraps(struct timespec *ts, struct timespec *delta) { /* * Don't allow the time to be set forward so far it * will wrap and become negative, thus allowing an * attacker to bypass the next check below. The * cutoff is 1 year before rollover occurs, so even * if the attacker uses adjtime(2) to move the time * past the cutoff, it will take a very long time * to get to the wrap point. */ if ((ts->tv_sec > LLONG_MAX - 365*24*60*60) || (delta->tv_sec < 0 || delta->tv_nsec < 0)) return true; return false; }