kern_time.c revision 1.177 
1/*	$NetBSD: kern_time.c,v 1.177 2013/03/29 10:34:12 martin Exp $	*/
2
3/*-
4 * Copyright (c) 2000, 2004, 2005, 2007, 2008, 2009 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christopher G. Demetriou, and by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*
33 * Copyright (c) 1982, 1986, 1989, 1993
34 *	The Regents of the University of California.  All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 *    notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 *    notice, this list of conditions and the following disclaimer in the
43 *    documentation and/or other materials provided with the distribution.
44 * 3. Neither the name of the University nor the names of its contributors
45 *    may be used to endorse or promote products derived from this software
46 *    without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 *	@(#)kern_time.c	8.4 (Berkeley) 5/26/95
61 */
62
63#include <sys/cdefs.h>
64__KERNEL_RCSID(0, "$NetBSD: kern_time.c,v 1.177 2013/03/29 10:34:12 martin Exp $");
65
66#include <sys/param.h>
67#include <sys/resourcevar.h>
68#include <sys/kernel.h>
69#include <sys/systm.h>
70#include <sys/proc.h>
71#include <sys/vnode.h>
72#include <sys/signalvar.h>
73#include <sys/syslog.h>
74#include <sys/timetc.h>
75#include <sys/timex.h>
76#include <sys/kauth.h>
77#include <sys/mount.h>
78#include <sys/syscallargs.h>
79#include <sys/cpu.h>
80
81static void	timer_intr(void *);
82static void	itimerfire(struct ptimer *);
83static void	itimerfree(struct ptimers *, int);
84
85kmutex_t	timer_lock;
86
87static void	*timer_sih;
88static TAILQ_HEAD(, ptimer) timer_queue;
89
90struct pool ptimer_pool, ptimers_pool;
91
92#define	CLOCK_VIRTUAL_P(clockid)	\
93	((clockid) == CLOCK_VIRTUAL || (clockid) == CLOCK_PROF)
94
95CTASSERT(ITIMER_REAL == CLOCK_REALTIME);
96CTASSERT(ITIMER_VIRTUAL == CLOCK_VIRTUAL);
97CTASSERT(ITIMER_PROF == CLOCK_PROF);
98CTASSERT(ITIMER_MONOTONIC == CLOCK_MONOTONIC);
99
100/*
101 * Initialize timekeeping.
102 */
103void
104time_init(void)
105{
106
107	pool_init(&ptimer_pool, sizeof(struct ptimer), 0, 0, 0, "ptimerpl",
108	    &pool_allocator_nointr, IPL_NONE);
109	pool_init(&ptimers_pool, sizeof(struct ptimers), 0, 0, 0, "ptimerspl",
110	    &pool_allocator_nointr, IPL_NONE);
111}
112
113void
114time_init2(void)
115{
116
117	TAILQ_INIT(&timer_queue);
118	mutex_init(&timer_lock, MUTEX_DEFAULT, IPL_SCHED);
119	timer_sih = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE,
120	    timer_intr, NULL);
121}
122
123/* Time of day and interval timer support.
124 *
125 * These routines provide the kernel entry points to get and set
126 * the time-of-day and per-process interval timers.  Subroutines
127 * here provide support for adding and subtracting timeval structures
128 * and decrementing interval timers, optionally reloading the interval
129 * timers when they expire.
130 */
131
132/* This function is used by clock_settime and settimeofday */
133static int
134settime1(struct proc *p, const struct timespec *ts, bool check_kauth)
135{
136	struct timespec delta, now;
137	int s;
138
139	/* WHAT DO WE DO ABOUT PENDING REAL-TIME TIMEOUTS??? */
140	s = splclock();
141	nanotime(&now);
142	timespecsub(ts, &now, &delta);
143
144	if (check_kauth && kauth_authorize_system(kauth_cred_get(),
145	    KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_SYSTEM, __UNCONST(ts),
146	    &delta, KAUTH_ARG(check_kauth ? false : true)) != 0) {
147		splx(s);
148		return (EPERM);
149	}
150
151#ifdef notyet
152	if ((delta.tv_sec < 86400) && securelevel > 0) { /* XXX elad - notyet */
153		splx(s);
154		return (EPERM);
155	}
156#endif
157
158	tc_setclock(ts);
159
160	timespecadd(&boottime, &delta, &boottime);
161
162	resettodr();
163	splx(s);
164
165	return (0);
166}
167
168int
169settime(struct proc *p, struct timespec *ts)
170{
171	return (settime1(p, ts, true));
172}
173
174/* ARGSUSED */
175int
176sys___clock_gettime50(struct lwp *l,
177    const struct sys___clock_gettime50_args *uap, register_t *retval)
178{
179	/* {
180		syscallarg(clockid_t) clock_id;
181		syscallarg(struct timespec *) tp;
182	} */
183	int error;
184	struct timespec ats;
185
186	error = clock_gettime1(SCARG(uap, clock_id), &ats);
187	if (error != 0)
188		return error;
189
190	return copyout(&ats, SCARG(uap, tp), sizeof(ats));
191}
192
193/* ARGSUSED */
194int
195sys___clock_settime50(struct lwp *l,
196    const struct sys___clock_settime50_args *uap, register_t *retval)
197{
198	/* {
199		syscallarg(clockid_t) clock_id;
200		syscallarg(const struct timespec *) tp;
201	} */
202	int error;
203	struct timespec ats;
204
205	if ((error = copyin(SCARG(uap, tp), &ats, sizeof(ats))) != 0)
206		return error;
207
208	return clock_settime1(l->l_proc, SCARG(uap, clock_id), &ats, true);
209}
210
211
212int
213clock_settime1(struct proc *p, clockid_t clock_id, const struct timespec *tp,
214    bool check_kauth)
215{
216	int error;
217
218	switch (clock_id) {
219	case CLOCK_REALTIME:
220		if ((error = settime1(p, tp, check_kauth)) != 0)
221			return (error);
222		break;
223	case CLOCK_MONOTONIC:
224		return (EINVAL);	/* read-only clock */
225	default:
226		return (EINVAL);
227	}
228
229	return 0;
230}
231
232int
233sys___clock_getres50(struct lwp *l, const struct sys___clock_getres50_args *uap,
234    register_t *retval)
235{
236	/* {
237		syscallarg(clockid_t) clock_id;
238		syscallarg(struct timespec *) tp;
239	} */
240	struct timespec ts;
241	int error = 0;
242
243	if ((error = clock_getres1(SCARG(uap, clock_id), &ts)) != 0)
244		return error;
245
246	if (SCARG(uap, tp))
247		error = copyout(&ts, SCARG(uap, tp), sizeof(ts));
248
249	return error;
250}
251
252int
253clock_getres1(clockid_t clock_id, struct timespec *ts)
254{
255
256	switch (clock_id) {
257	case CLOCK_REALTIME:
258	case CLOCK_MONOTONIC:
259		ts->tv_sec = 0;
260		if (tc_getfrequency() > 1000000000)
261			ts->tv_nsec = 1;
262		else
263			ts->tv_nsec = 1000000000 / tc_getfrequency();
264		break;
265	default:
266		return EINVAL;
267	}
268
269	return 0;
270}
271
272/* ARGSUSED */
273int
274sys___nanosleep50(struct lwp *l, const struct sys___nanosleep50_args *uap,
275    register_t *retval)
276{
277	/* {
278		syscallarg(struct timespec *) rqtp;
279		syscallarg(struct timespec *) rmtp;
280	} */
281	struct timespec rmt, rqt;
282	int error, error1;
283
284	error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec));
285	if (error)
286		return (error);
287
288	error = nanosleep1(l, CLOCK_MONOTONIC, 0, &rqt,
289	    SCARG(uap, rmtp) ? &rmt : NULL);
290	if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR))
291		return error;
292
293	error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt));
294	return error1 ? error1 : error;
295}
296
297/* ARGSUSED */
298int
299sys_clock_nanosleep(struct lwp *l, const struct sys_clock_nanosleep_args *uap,
300    register_t *retval)
301{
302	/* {
303		syscallarg(clockid_t) clock_id;
304		syscallarg(int) flags;
305		syscallarg(struct timespec *) rqtp;
306		syscallarg(struct timespec *) rmtp;
307	} */
308	struct timespec rmt, rqt;
309	int error, error1;
310
311	error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec));
312	if (error)
313		return (error);
314
315	error = nanosleep1(l, SCARG(uap, clock_id), SCARG(uap, flags), &rqt,
316	    SCARG(uap, rmtp) ? &rmt : NULL);
317	if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR))
318		return error;
319
320	error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt));
321	return error1 ? error1 : error;
322}
323
324int
325nanosleep1(struct lwp *l, clockid_t clock_id, int flags, struct timespec *rqt,
326    struct timespec *rmt)
327{
328	struct timespec rmtstart;
329	int error, timo;
330
331	if ((error = ts2timo(clock_id, flags, rqt, &timo, &rmtstart)) != 0) {
332		if (error == ETIMEDOUT)
333			timo = 0;
334	}
335
336	/*
337	 * Avoid inadvertently sleeping forever
338	 */
339	if (timo == 0)
340		timo = 1;
341again:
342	error = kpause("nanoslp", true, timo, NULL);
343	if (rmt != NULL || error == 0) {
344		struct timespec rmtend;
345		struct timespec t0;
346		struct timespec *t;
347
348		(void)clock_gettime1(clock_id, &rmtend);
349		t = (rmt != NULL) ? rmt : &t0;
350		timespecsub(&rmtend, &rmtstart, t);
351		timespecsub(rqt, t, t);
352		if (t->tv_sec < 0)
353			timespecclear(t);
354		if (error == 0) {
355			timo = tstohz(t);
356			if (timo > 0)
357				goto again;
358		}
359	}
360
361	if (error == ERESTART)
362		error = EINTR;
363	if (error == EWOULDBLOCK)
364		error = 0;
365
366	return error;
367}
368
369/* ARGSUSED */
370int
371sys___gettimeofday50(struct lwp *l, const struct sys___gettimeofday50_args *uap,
372    register_t *retval)
373{
374	/* {
375		syscallarg(struct timeval *) tp;
376		syscallarg(void *) tzp;		really "struct timezone *";
377	} */
378	struct timeval atv;
379	int error = 0;
380	struct timezone tzfake;
381
382	if (SCARG(uap, tp)) {
383		microtime(&atv);
384		error = copyout(&atv, SCARG(uap, tp), sizeof(atv));
385		if (error)
386			return (error);
387	}
388	if (SCARG(uap, tzp)) {
389		/*
390		 * NetBSD has no kernel notion of time zone, so we just
391		 * fake up a timezone struct and return it if demanded.
392		 */
393		tzfake.tz_minuteswest = 0;
394		tzfake.tz_dsttime = 0;
395		error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake));
396	}
397	return (error);
398}
399
400/* ARGSUSED */
401int
402sys___settimeofday50(struct lwp *l, const struct sys___settimeofday50_args *uap,
403    register_t *retval)
404{
405	/* {
406		syscallarg(const struct timeval *) tv;
407		syscallarg(const void *) tzp; really "const struct timezone *";
408	} */
409
410	return settimeofday1(SCARG(uap, tv), true, SCARG(uap, tzp), l, true);
411}
412
413int
414settimeofday1(const struct timeval *utv, bool userspace,
415    const void *utzp, struct lwp *l, bool check_kauth)
416{
417	struct timeval atv;
418	struct timespec ts;
419	int error;
420
421	/* Verify all parameters before changing time. */
422
423	/*
424	 * NetBSD has no kernel notion of time zone, and only an
425	 * obsolete program would try to set it, so we log a warning.
426	 */
427	if (utzp)
428		log(LOG_WARNING, "pid %d attempted to set the "
429		    "(obsolete) kernel time zone\n", l->l_proc->p_pid);
430
431	if (utv == NULL)
432		return 0;
433
434	if (userspace) {
435		if ((error = copyin(utv, &atv, sizeof(atv))) != 0)
436			return error;
437		utv = &atv;
438	}
439
440	TIMEVAL_TO_TIMESPEC(utv, &ts);
441	return settime1(l->l_proc, &ts, check_kauth);
442}
443
444int	time_adjusted;			/* set if an adjustment is made */
445
446/* ARGSUSED */
447int
448sys___adjtime50(struct lwp *l, const struct sys___adjtime50_args *uap,
449    register_t *retval)
450{
451	/* {
452		syscallarg(const struct timeval *) delta;
453		syscallarg(struct timeval *) olddelta;
454	} */
455	int error = 0;
456	struct timeval atv, oldatv;
457
458	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_TIME,
459	    KAUTH_REQ_SYSTEM_TIME_ADJTIME, NULL, NULL, NULL)) != 0)
460		return error;
461
462	if (SCARG(uap, delta)) {
463		error = copyin(SCARG(uap, delta), &atv,
464		    sizeof(*SCARG(uap, delta)));
465		if (error)
466			return (error);
467	}
468	adjtime1(SCARG(uap, delta) ? &atv : NULL,
469	    SCARG(uap, olddelta) ? &oldatv : NULL, l->l_proc);
470	if (SCARG(uap, olddelta))
471		error = copyout(&oldatv, SCARG(uap, olddelta),
472		    sizeof(*SCARG(uap, olddelta)));
473	return error;
474}
475
476void
477adjtime1(const struct timeval *delta, struct timeval *olddelta, struct proc *p)
478{
479	extern int64_t time_adjtime;  /* in kern_ntptime.c */
480
481	if (olddelta) {
482		mutex_spin_enter(&timecounter_lock);
483		olddelta->tv_sec = time_adjtime / 1000000;
484		olddelta->tv_usec = time_adjtime % 1000000;
485		if (olddelta->tv_usec < 0) {
486			olddelta->tv_usec += 1000000;
487			olddelta->tv_sec--;
488		}
489		mutex_spin_exit(&timecounter_lock);
490	}
491
492	if (delta) {
493		mutex_spin_enter(&timecounter_lock);
494		time_adjtime = delta->tv_sec * 1000000 + delta->tv_usec;
495
496		if (time_adjtime) {
497			/* We need to save the system time during shutdown */
498			time_adjusted |= 1;
499		}
500		mutex_spin_exit(&timecounter_lock);
501	}
502}
503
504/*
505 * Interval timer support. Both the BSD getitimer() family and the POSIX
506 * timer_*() family of routines are supported.
507 *
508 * All timers are kept in an array pointed to by p_timers, which is
509 * allocated on demand - many processes don't use timers at all. The
510 * first three elements in this array are reserved for the BSD timers:
511 * element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, element
512 * 2 is ITIMER_PROF, and element 3 is ITIMER_MONOTONIC. The rest may be
513 * allocated by the timer_create() syscall.
514 *
515 * Realtime timers are kept in the ptimer structure as an absolute
516 * time; virtual time timers are kept as a linked list of deltas.
517 * Virtual time timers are processed in the hardclock() routine of
518 * kern_clock.c.  The real time timer is processed by a callout
519 * routine, called from the softclock() routine.  Since a callout may
520 * be delayed in real time due to interrupt processing in the system,
521 * it is possible for the real time timeout routine (realtimeexpire,
522 * given below), to be delayed in real time past when it is supposed
523 * to occur.  It does not suffice, therefore, to reload the real timer
524 * .it_value from the real time timers .it_interval.  Rather, we
525 * compute the next time in absolute time the timer should go off.  */
526
527/* Allocate a POSIX realtime timer. */
528int
529sys_timer_create(struct lwp *l, const struct sys_timer_create_args *uap,
530    register_t *retval)
531{
532	/* {
533		syscallarg(clockid_t) clock_id;
534		syscallarg(struct sigevent *) evp;
535		syscallarg(timer_t *) timerid;
536	} */
537
538	return timer_create1(SCARG(uap, timerid), SCARG(uap, clock_id),
539	    SCARG(uap, evp), copyin, l);
540}
541
542int
543timer_create1(timer_t *tid, clockid_t id, struct sigevent *evp,
544    copyin_t fetch_event, struct lwp *l)
545{
546	int error;
547	timer_t timerid;
548	struct ptimers *pts;
549	struct ptimer *pt;
550	struct proc *p;
551
552	p = l->l_proc;
553
554	if ((u_int)id > CLOCK_MONOTONIC)
555		return (EINVAL);
556
557	if ((pts = p->p_timers) == NULL)
558		pts = timers_alloc(p);
559
560	pt = pool_get(&ptimer_pool, PR_WAITOK);
561	if (evp != NULL) {
562		if (((error =
563		    (*fetch_event)(evp, &pt->pt_ev, sizeof(pt->pt_ev))) != 0) ||
564		    ((pt->pt_ev.sigev_notify < SIGEV_NONE) ||
565			(pt->pt_ev.sigev_notify > SIGEV_SA)) ||
566			(pt->pt_ev.sigev_notify == SIGEV_SIGNAL &&
567			 (pt->pt_ev.sigev_signo <= 0 ||
568			  pt->pt_ev.sigev_signo >= NSIG))) {
569			pool_put(&ptimer_pool, pt);
570			return (error ? error : EINVAL);
571		}
572	}
573
574	/* Find a free timer slot, skipping those reserved for setitimer(). */
575	mutex_spin_enter(&timer_lock);
576	for (timerid = 3; timerid < TIMER_MAX; timerid++)
577		if (pts->pts_timers[timerid] == NULL)
578			break;
579	if (timerid == TIMER_MAX) {
580		mutex_spin_exit(&timer_lock);
581		pool_put(&ptimer_pool, pt);
582		return EAGAIN;
583	}
584	if (evp == NULL) {
585		pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
586		switch (id) {
587		case CLOCK_REALTIME:
588		case CLOCK_MONOTONIC:
589			pt->pt_ev.sigev_signo = SIGALRM;
590			break;
591		case CLOCK_VIRTUAL:
592			pt->pt_ev.sigev_signo = SIGVTALRM;
593			break;
594		case CLOCK_PROF:
595			pt->pt_ev.sigev_signo = SIGPROF;
596			break;
597		}
598		pt->pt_ev.sigev_value.sival_int = timerid;
599	}
600	pt->pt_info.ksi_signo = pt->pt_ev.sigev_signo;
601	pt->pt_info.ksi_errno = 0;
602	pt->pt_info.ksi_code = 0;
603	pt->pt_info.ksi_pid = p->p_pid;
604	pt->pt_info.ksi_uid = kauth_cred_getuid(l->l_cred);
605	pt->pt_info.ksi_value = pt->pt_ev.sigev_value;
606	pt->pt_type = id;
607	pt->pt_proc = p;
608	pt->pt_overruns = 0;
609	pt->pt_poverruns = 0;
610	pt->pt_entry = timerid;
611	pt->pt_queued = false;
612	timespecclear(&pt->pt_time.it_value);
613	if (!CLOCK_VIRTUAL_P(id))
614		callout_init(&pt->pt_ch, CALLOUT_MPSAFE);
615	else
616		pt->pt_active = 0;
617
618	pts->pts_timers[timerid] = pt;
619	mutex_spin_exit(&timer_lock);
620
621	return copyout(&timerid, tid, sizeof(timerid));
622}
623
624/* Delete a POSIX realtime timer */
625int
626sys_timer_delete(struct lwp *l, const struct sys_timer_delete_args *uap,
627    register_t *retval)
628{
629	/* {
630		syscallarg(timer_t) timerid;
631	} */
632	struct proc *p = l->l_proc;
633	timer_t timerid;
634	struct ptimers *pts;
635	struct ptimer *pt, *ptn;
636
637	timerid = SCARG(uap, timerid);
638	pts = p->p_timers;
639
640	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
641		return (EINVAL);
642
643	mutex_spin_enter(&timer_lock);
644	if ((pt = pts->pts_timers[timerid]) == NULL) {
645		mutex_spin_exit(&timer_lock);
646		return (EINVAL);
647	}
648	if (CLOCK_VIRTUAL_P(pt->pt_type)) {
649		if (pt->pt_active) {
650			ptn = LIST_NEXT(pt, pt_list);
651			LIST_REMOVE(pt, pt_list);
652			for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
653				timespecadd(&pt->pt_time.it_value,
654				    &ptn->pt_time.it_value,
655				    &ptn->pt_time.it_value);
656			pt->pt_active = 0;
657		}
658	}
659	itimerfree(pts, timerid);
660
661	return (0);
662}
663
664/*
665 * Set up the given timer. The value in pt->pt_time.it_value is taken
666 * to be an absolute time for CLOCK_REALTIME/CLOCK_MONOTONIC timers and
667 * a relative time for CLOCK_VIRTUAL/CLOCK_PROF timers.
668 */
669void
670timer_settime(struct ptimer *pt)
671{
672	struct ptimer *ptn, *pptn;
673	struct ptlist *ptl;
674
675	KASSERT(mutex_owned(&timer_lock));
676
677	if (!CLOCK_VIRTUAL_P(pt->pt_type)) {
678		callout_halt(&pt->pt_ch, &timer_lock);
679		if (timespecisset(&pt->pt_time.it_value)) {
680			/*
681			 * Don't need to check tshzto() return value, here.
682			 * callout_reset() does it for us.
683			 */
684			callout_reset(&pt->pt_ch,
685			    pt->pt_type == CLOCK_MONOTONIC ?
686			    tshztoup(&pt->pt_time.it_value) :
687			    tshzto(&pt->pt_time.it_value),
688			    realtimerexpire, pt);
689		}
690	} else {
691		if (pt->pt_active) {
692			ptn = LIST_NEXT(pt, pt_list);
693			LIST_REMOVE(pt, pt_list);
694			for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
695				timespecadd(&pt->pt_time.it_value,
696				    &ptn->pt_time.it_value,
697				    &ptn->pt_time.it_value);
698		}
699		if (timespecisset(&pt->pt_time.it_value)) {
700			if (pt->pt_type == CLOCK_VIRTUAL)
701				ptl = &pt->pt_proc->p_timers->pts_virtual;
702			else
703				ptl = &pt->pt_proc->p_timers->pts_prof;
704
705			for (ptn = LIST_FIRST(ptl), pptn = NULL;
706			     ptn && timespeccmp(&pt->pt_time.it_value,
707				 &ptn->pt_time.it_value, >);
708			     pptn = ptn, ptn = LIST_NEXT(ptn, pt_list))
709				timespecsub(&pt->pt_time.it_value,
710				    &ptn->pt_time.it_value,
711				    &pt->pt_time.it_value);
712
713			if (pptn)
714				LIST_INSERT_AFTER(pptn, pt, pt_list);
715			else
716				LIST_INSERT_HEAD(ptl, pt, pt_list);
717
718			for ( ; ptn ; ptn = LIST_NEXT(ptn, pt_list))
719				timespecsub(&ptn->pt_time.it_value,
720				    &pt->pt_time.it_value,
721				    &ptn->pt_time.it_value);
722
723			pt->pt_active = 1;
724		} else
725			pt->pt_active = 0;
726	}
727}
728
729void
730timer_gettime(struct ptimer *pt, struct itimerspec *aits)
731{
732	struct timespec now;
733	struct ptimer *ptn;
734
735	KASSERT(mutex_owned(&timer_lock));
736
737	*aits = pt->pt_time;
738	if (!CLOCK_VIRTUAL_P(pt->pt_type)) {
739		/*
740		 * Convert from absolute to relative time in .it_value
741		 * part of real time timer.  If time for real time
742		 * timer has passed return 0, else return difference
743		 * between current time and time for the timer to go
744		 * off.
745		 */
746		if (timespecisset(&aits->it_value)) {
747			if (pt->pt_type == CLOCK_REALTIME) {
748				getnanotime(&now);
749			} else { /* CLOCK_MONOTONIC */
750				getnanouptime(&now);
751			}
752			if (timespeccmp(&aits->it_value, &now, <))
753				timespecclear(&aits->it_value);
754			else
755				timespecsub(&aits->it_value, &now,
756				    &aits->it_value);
757		}
758	} else if (pt->pt_active) {
759		if (pt->pt_type == CLOCK_VIRTUAL)
760			ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_virtual);
761		else
762			ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_prof);
763		for ( ; ptn && ptn != pt; ptn = LIST_NEXT(ptn, pt_list))
764			timespecadd(&aits->it_value,
765			    &ptn->pt_time.it_value, &aits->it_value);
766		KASSERT(ptn != NULL); /* pt should be findable on the list */
767	} else
768		timespecclear(&aits->it_value);
769}
770
771
772
773/* Set and arm a POSIX realtime timer */
774int
775sys___timer_settime50(struct lwp *l,
776    const struct sys___timer_settime50_args *uap,
777    register_t *retval)
778{
779	/* {
780		syscallarg(timer_t) timerid;
781		syscallarg(int) flags;
782		syscallarg(const struct itimerspec *) value;
783		syscallarg(struct itimerspec *) ovalue;
784	} */
785	int error;
786	struct itimerspec value, ovalue, *ovp = NULL;
787
788	if ((error = copyin(SCARG(uap, value), &value,
789	    sizeof(struct itimerspec))) != 0)
790		return (error);
791
792	if (SCARG(uap, ovalue))
793		ovp = &ovalue;
794
795	if ((error = dotimer_settime(SCARG(uap, timerid), &value, ovp,
796	    SCARG(uap, flags), l->l_proc)) != 0)
797		return error;
798
799	if (ovp)
800		return copyout(&ovalue, SCARG(uap, ovalue),
801		    sizeof(struct itimerspec));
802	return 0;
803}
804
805int
806dotimer_settime(int timerid, struct itimerspec *value,
807    struct itimerspec *ovalue, int flags, struct proc *p)
808{
809	struct timespec now;
810	struct itimerspec val, oval;
811	struct ptimers *pts;
812	struct ptimer *pt;
813	int error;
814
815	pts = p->p_timers;
816
817	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
818		return EINVAL;
819	val = *value;
820	if ((error = itimespecfix(&val.it_value)) != 0 ||
821	    (error = itimespecfix(&val.it_interval)) != 0)
822		return error;
823
824	mutex_spin_enter(&timer_lock);
825	if ((pt = pts->pts_timers[timerid]) == NULL) {
826		mutex_spin_exit(&timer_lock);
827		return EINVAL;
828	}
829
830	oval = pt->pt_time;
831	pt->pt_time = val;
832
833	/*
834	 * If we've been passed a relative time for a realtime timer,
835	 * convert it to absolute; if an absolute time for a virtual
836	 * timer, convert it to relative and make sure we don't set it
837	 * to zero, which would cancel the timer, or let it go
838	 * negative, which would confuse the comparison tests.
839	 */
840	if (timespecisset(&pt->pt_time.it_value)) {
841		if (!CLOCK_VIRTUAL_P(pt->pt_type)) {
842			if ((flags & TIMER_ABSTIME) == 0) {
843				if (pt->pt_type == CLOCK_REALTIME) {
844					getnanotime(&now);
845				} else { /* CLOCK_MONOTONIC */
846					getnanouptime(&now);
847				}
848				timespecadd(&pt->pt_time.it_value, &now,
849				    &pt->pt_time.it_value);
850			}
851		} else {
852			if ((flags & TIMER_ABSTIME) != 0) {
853				getnanotime(&now);
854				timespecsub(&pt->pt_time.it_value, &now,
855				    &pt->pt_time.it_value);
856				if (!timespecisset(&pt->pt_time.it_value) ||
857				    pt->pt_time.it_value.tv_sec < 0) {
858					pt->pt_time.it_value.tv_sec = 0;
859					pt->pt_time.it_value.tv_nsec = 1;
860				}
861			}
862		}
863	}
864
865	timer_settime(pt);
866	mutex_spin_exit(&timer_lock);
867
868	if (ovalue)
869		*ovalue = oval;
870
871	return (0);
872}
873
874/* Return the time remaining until a POSIX timer fires. */
875int
876sys___timer_gettime50(struct lwp *l,
877    const struct sys___timer_gettime50_args *uap, register_t *retval)
878{
879	/* {
880		syscallarg(timer_t) timerid;
881		syscallarg(struct itimerspec *) value;
882	} */
883	struct itimerspec its;
884	int error;
885
886	if ((error = dotimer_gettime(SCARG(uap, timerid), l->l_proc,
887	    &its)) != 0)
888		return error;
889
890	return copyout(&its, SCARG(uap, value), sizeof(its));
891}
892
893int
894dotimer_gettime(int timerid, struct proc *p, struct itimerspec *its)
895{
896	struct ptimer *pt;
897	struct ptimers *pts;
898
899	pts = p->p_timers;
900	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
901		return (EINVAL);
902	mutex_spin_enter(&timer_lock);
903	if ((pt = pts->pts_timers[timerid]) == NULL) {
904		mutex_spin_exit(&timer_lock);
905		return (EINVAL);
906	}
907	timer_gettime(pt, its);
908	mutex_spin_exit(&timer_lock);
909
910	return 0;
911}
912
913/*
914 * Return the count of the number of times a periodic timer expired
915 * while a notification was already pending. The counter is reset when
916 * a timer expires and a notification can be posted.
917 */
918int
919sys_timer_getoverrun(struct lwp *l, const struct sys_timer_getoverrun_args *uap,
920    register_t *retval)
921{
922	/* {
923		syscallarg(timer_t) timerid;
924	} */
925	struct proc *p = l->l_proc;
926	struct ptimers *pts;
927	int timerid;
928	struct ptimer *pt;
929
930	timerid = SCARG(uap, timerid);
931
932	pts = p->p_timers;
933	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
934		return (EINVAL);
935	mutex_spin_enter(&timer_lock);
936	if ((pt = pts->pts_timers[timerid]) == NULL) {
937		mutex_spin_exit(&timer_lock);
938		return (EINVAL);
939	}
940	*retval = pt->pt_poverruns;
941	mutex_spin_exit(&timer_lock);
942
943	return (0);
944}
945
946/*
947 * Real interval timer expired:
948 * send process whose timer expired an alarm signal.
949 * If time is not set up to reload, then just return.
950 * Else compute next time timer should go off which is > current time.
951 * This is where delay in processing this timeout causes multiple
952 * SIGALRM calls to be compressed into one.
953 */
954void
955realtimerexpire(void *arg)
956{
957	uint64_t last_val, next_val, interval, now_ns;
958	struct timespec now, next;
959	struct ptimer *pt;
960	int backwards;
961
962	pt = arg;
963
964	mutex_spin_enter(&timer_lock);
965	itimerfire(pt);
966
967	if (!timespecisset(&pt->pt_time.it_interval)) {
968		timespecclear(&pt->pt_time.it_value);
969		mutex_spin_exit(&timer_lock);
970		return;
971	}
972
973	if (pt->pt_type == CLOCK_MONOTONIC) {
974		getnanouptime(&now);
975	} else {
976		getnanotime(&now);
977	}
978	backwards = (timespeccmp(&pt->pt_time.it_value, &now, >));
979	timespecadd(&pt->pt_time.it_value, &pt->pt_time.it_interval, &next);
980	/* Handle the easy case of non-overflown timers first. */
981	if (!backwards && timespeccmp(&next, &now, >)) {
982		pt->pt_time.it_value = next;
983	} else {
984		now_ns = timespec2ns(&now);
985		last_val = timespec2ns(&pt->pt_time.it_value);
986		interval = timespec2ns(&pt->pt_time.it_interval);
987
988		next_val = now_ns +
989		    (now_ns - last_val + interval - 1) % interval;
990
991		if (backwards)
992			next_val += interval;
993		else
994			pt->pt_overruns += (now_ns - last_val) / interval;
995
996		pt->pt_time.it_value.tv_sec = next_val / 1000000000;
997		pt->pt_time.it_value.tv_nsec = next_val % 1000000000;
998	}
999
1000	/*
1001	 * Don't need to check tshzto() return value, here.
1002	 * callout_reset() does it for us.
1003	 */
1004	callout_reset(&pt->pt_ch, pt->pt_type == CLOCK_MONOTONIC ?
1005	    tshztoup(&pt->pt_time.it_value) : tshzto(&pt->pt_time.it_value),
1006	    realtimerexpire, pt);
1007	mutex_spin_exit(&timer_lock);
1008}
1009
1010/* BSD routine to get the value of an interval timer. */
1011/* ARGSUSED */
1012int
1013sys___getitimer50(struct lwp *l, const struct sys___getitimer50_args *uap,
1014    register_t *retval)
1015{
1016	/* {
1017		syscallarg(int) which;
1018		syscallarg(struct itimerval *) itv;
1019	} */
1020	struct proc *p = l->l_proc;
1021	struct itimerval aitv;
1022	int error;
1023
1024	error = dogetitimer(p, SCARG(uap, which), &aitv);
1025	if (error)
1026		return error;
1027	return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval)));
1028}
1029
1030int
1031dogetitimer(struct proc *p, int which, struct itimerval *itvp)
1032{
1033	struct ptimers *pts;
1034	struct ptimer *pt;
1035	struct itimerspec its;
1036
1037	if ((u_int)which > ITIMER_MONOTONIC)
1038		return (EINVAL);
1039
1040	mutex_spin_enter(&timer_lock);
1041	pts = p->p_timers;
1042	if (pts == NULL || (pt = pts->pts_timers[which]) == NULL) {
1043		timerclear(&itvp->it_value);
1044		timerclear(&itvp->it_interval);
1045	} else {
1046		timer_gettime(pt, &its);
1047		TIMESPEC_TO_TIMEVAL(&itvp->it_value, &its.it_value);
1048		TIMESPEC_TO_TIMEVAL(&itvp->it_interval, &its.it_interval);
1049	}
1050	mutex_spin_exit(&timer_lock);
1051
1052	return 0;
1053}
1054
1055/* BSD routine to set/arm an interval timer. */
1056/* ARGSUSED */
1057int
1058sys___setitimer50(struct lwp *l, const struct sys___setitimer50_args *uap,
1059    register_t *retval)
1060{
1061	/* {
1062		syscallarg(int) which;
1063		syscallarg(const struct itimerval *) itv;
1064		syscallarg(struct itimerval *) oitv;
1065	} */
1066	struct proc *p = l->l_proc;
1067	int which = SCARG(uap, which);
1068	struct sys___getitimer50_args getargs;
1069	const struct itimerval *itvp;
1070	struct itimerval aitv;
1071	int error;
1072
1073	if ((u_int)which > ITIMER_MONOTONIC)
1074		return (EINVAL);
1075	itvp = SCARG(uap, itv);
1076	if (itvp &&
1077	    (error = copyin(itvp, &aitv, sizeof(struct itimerval))) != 0)
1078		return (error);
1079	if (SCARG(uap, oitv) != NULL) {
1080		SCARG(&getargs, which) = which;
1081		SCARG(&getargs, itv) = SCARG(uap, oitv);
1082		if ((error = sys___getitimer50(l, &getargs, retval)) != 0)
1083			return (error);
1084	}
1085	if (itvp == 0)
1086		return (0);
1087
1088	return dosetitimer(p, which, &aitv);
1089}
1090
1091int
1092dosetitimer(struct proc *p, int which, struct itimerval *itvp)
1093{
1094	struct timespec now;
1095	struct ptimers *pts;
1096	struct ptimer *pt, *spare;
1097
1098	KASSERT((u_int)which <= CLOCK_MONOTONIC);
1099	if (itimerfix(&itvp->it_value) || itimerfix(&itvp->it_interval))
1100		return (EINVAL);
1101
1102	/*
1103	 * Don't bother allocating data structures if the process just
1104	 * wants to clear the timer.
1105	 */
1106	spare = NULL;
1107	pts = p->p_timers;
1108 retry:
1109	if (!timerisset(&itvp->it_value) && (pts == NULL ||
1110	    pts->pts_timers[which] == NULL))
1111		return (0);
1112	if (pts == NULL)
1113		pts = timers_alloc(p);
1114	mutex_spin_enter(&timer_lock);
1115	pt = pts->pts_timers[which];
1116	if (pt == NULL) {
1117		if (spare == NULL) {
1118			mutex_spin_exit(&timer_lock);
1119			spare = pool_get(&ptimer_pool, PR_WAITOK);
1120			goto retry;
1121		}
1122		pt = spare;
1123		spare = NULL;
1124		pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
1125		pt->pt_ev.sigev_value.sival_int = which;
1126		pt->pt_overruns = 0;
1127		pt->pt_proc = p;
1128		pt->pt_type = which;
1129		pt->pt_entry = which;
1130		pt->pt_queued = false;
1131		if (pt->pt_type == CLOCK_REALTIME)
1132			callout_init(&pt->pt_ch, CALLOUT_MPSAFE);
1133		else
1134			pt->pt_active = 0;
1135
1136		switch (which) {
1137		case ITIMER_REAL:
1138		case ITIMER_MONOTONIC:
1139			pt->pt_ev.sigev_signo = SIGALRM;
1140			break;
1141		case ITIMER_VIRTUAL:
1142			pt->pt_ev.sigev_signo = SIGVTALRM;
1143			break;
1144		case ITIMER_PROF:
1145			pt->pt_ev.sigev_signo = SIGPROF;
1146			break;
1147		}
1148		pts->pts_timers[which] = pt;
1149	}
1150
1151	TIMEVAL_TO_TIMESPEC(&itvp->it_value, &pt->pt_time.it_value);
1152	TIMEVAL_TO_TIMESPEC(&itvp->it_interval, &pt->pt_time.it_interval);
1153
1154	if (timespecisset(&pt->pt_time.it_value)) {
1155		/* Convert to absolute time */
1156		/* XXX need to wrap in splclock for timecounters case? */
1157		switch (which) {
1158		case ITIMER_REAL:
1159			getnanotime(&now);
1160			timespecadd(&pt->pt_time.it_value, &now,
1161			    &pt->pt_time.it_value);
1162			break;
1163		case ITIMER_MONOTONIC:
1164			getnanouptime(&now);
1165			timespecadd(&pt->pt_time.it_value, &now,
1166			    &pt->pt_time.it_value);
1167			break;
1168		default:
1169			break;
1170		}
1171	}
1172	timer_settime(pt);
1173	mutex_spin_exit(&timer_lock);
1174	if (spare != NULL)
1175		pool_put(&ptimer_pool, spare);
1176
1177	return (0);
1178}
1179
1180/* Utility routines to manage the array of pointers to timers. */
1181struct ptimers *
1182timers_alloc(struct proc *p)
1183{
1184	struct ptimers *pts;
1185	int i;
1186
1187	pts = pool_get(&ptimers_pool, PR_WAITOK);
1188	LIST_INIT(&pts->pts_virtual);
1189	LIST_INIT(&pts->pts_prof);
1190	for (i = 0; i < TIMER_MAX; i++)
1191		pts->pts_timers[i] = NULL;
1192	pts->pts_fired = 0;
1193	mutex_spin_enter(&timer_lock);
1194	if (p->p_timers == NULL) {
1195		p->p_timers = pts;
1196		mutex_spin_exit(&timer_lock);
1197		return pts;
1198	}
1199	mutex_spin_exit(&timer_lock);
1200	pool_put(&ptimers_pool, pts);
1201	return p->p_timers;
1202}
1203
1204/*
1205 * Clean up the per-process timers. If "which" is set to TIMERS_ALL,
1206 * then clean up all timers and free all the data structures. If
1207 * "which" is set to TIMERS_POSIX, only clean up the timers allocated
1208 * by timer_create(), not the BSD setitimer() timers, and only free the
1209 * structure if none of those remain.
1210 */
1211void
1212timers_free(struct proc *p, int which)
1213{
1214	struct ptimers *pts;
1215	struct ptimer *ptn;
1216	struct timespec ts;
1217	int i;
1218
1219	if (p->p_timers == NULL)
1220		return;
1221
1222	pts = p->p_timers;
1223	mutex_spin_enter(&timer_lock);
1224	if (which == TIMERS_ALL) {
1225		p->p_timers = NULL;
1226		i = 0;
1227	} else {
1228		timespecclear(&ts);
1229		for (ptn = LIST_FIRST(&pts->pts_virtual);
1230		     ptn && ptn != pts->pts_timers[ITIMER_VIRTUAL];
1231		     ptn = LIST_NEXT(ptn, pt_list)) {
1232			KASSERT(ptn->pt_type == CLOCK_VIRTUAL);
1233			timespecadd(&ts, &ptn->pt_time.it_value, &ts);
1234		}
1235		LIST_FIRST(&pts->pts_virtual) = NULL;
1236		if (ptn) {
1237			KASSERT(ptn->pt_type == CLOCK_VIRTUAL);
1238			timespecadd(&ts, &ptn->pt_time.it_value,
1239			    &ptn->pt_time.it_value);
1240			LIST_INSERT_HEAD(&pts->pts_virtual, ptn, pt_list);
1241		}
1242		timespecclear(&ts);
1243		for (ptn = LIST_FIRST(&pts->pts_prof);
1244		     ptn && ptn != pts->pts_timers[ITIMER_PROF];
1245		     ptn = LIST_NEXT(ptn, pt_list)) {
1246			KASSERT(ptn->pt_type == CLOCK_PROF);
1247			timespecadd(&ts, &ptn->pt_time.it_value, &ts);
1248		}
1249		LIST_FIRST(&pts->pts_prof) = NULL;
1250		if (ptn) {
1251			KASSERT(ptn->pt_type == CLOCK_PROF);
1252			timespecadd(&ts, &ptn->pt_time.it_value,
1253			    &ptn->pt_time.it_value);
1254			LIST_INSERT_HEAD(&pts->pts_prof, ptn, pt_list);
1255		}
1256		i = 3;
1257	}
1258	for ( ; i < TIMER_MAX; i++) {
1259		if (pts->pts_timers[i] != NULL) {
1260			itimerfree(pts, i);
1261			mutex_spin_enter(&timer_lock);
1262		}
1263	}
1264	if (pts->pts_timers[0] == NULL && pts->pts_timers[1] == NULL &&
1265	    pts->pts_timers[2] == NULL) {
1266		p->p_timers = NULL;
1267		mutex_spin_exit(&timer_lock);
1268		pool_put(&ptimers_pool, pts);
1269	} else
1270		mutex_spin_exit(&timer_lock);
1271}
1272
1273static void
1274itimerfree(struct ptimers *pts, int index)
1275{
1276	struct ptimer *pt;
1277
1278	KASSERT(mutex_owned(&timer_lock));
1279
1280	pt = pts->pts_timers[index];
1281	pts->pts_timers[index] = NULL;
1282	if (!CLOCK_VIRTUAL_P(pt->pt_type))
1283		callout_halt(&pt->pt_ch, &timer_lock);
1284	if (pt->pt_queued)
1285		TAILQ_REMOVE(&timer_queue, pt, pt_chain);
1286	mutex_spin_exit(&timer_lock);
1287	if (!CLOCK_VIRTUAL_P(pt->pt_type))
1288		callout_destroy(&pt->pt_ch);
1289	pool_put(&ptimer_pool, pt);
1290}
1291
1292/*
1293 * Decrement an interval timer by a specified number
1294 * of nanoseconds, which must be less than a second,
1295 * i.e. < 1000000000.  If the timer expires, then reload
1296 * it.  In this case, carry over (nsec - old value) to
1297 * reduce the value reloaded into the timer so that
1298 * the timer does not drift.  This routine assumes
1299 * that it is called in a context where the timers
1300 * on which it is operating cannot change in value.
1301 */
1302static int
1303itimerdecr(struct ptimer *pt, int nsec)
1304{
1305	struct itimerspec *itp;
1306
1307	KASSERT(mutex_owned(&timer_lock));
1308	KASSERT(CLOCK_VIRTUAL_P(pt->pt_type));
1309
1310	itp = &pt->pt_time;
1311	if (itp->it_value.tv_nsec < nsec) {
1312		if (itp->it_value.tv_sec == 0) {
1313			/* expired, and already in next interval */
1314			nsec -= itp->it_value.tv_nsec;
1315			goto expire;
1316		}
1317		itp->it_value.tv_nsec += 1000000000;
1318		itp->it_value.tv_sec--;
1319	}
1320	itp->it_value.tv_nsec -= nsec;
1321	nsec = 0;
1322	if (timespecisset(&itp->it_value))
1323		return (1);
1324	/* expired, exactly at end of interval */
1325expire:
1326	if (timespecisset(&itp->it_interval)) {
1327		itp->it_value = itp->it_interval;
1328		itp->it_value.tv_nsec -= nsec;
1329		if (itp->it_value.tv_nsec < 0) {
1330			itp->it_value.tv_nsec += 1000000000;
1331			itp->it_value.tv_sec--;
1332		}
1333		timer_settime(pt);
1334	} else
1335		itp->it_value.tv_nsec = 0;		/* sec is already 0 */
1336	return (0);
1337}
1338
1339static void
1340itimerfire(struct ptimer *pt)
1341{
1342
1343	KASSERT(mutex_owned(&timer_lock));
1344
1345	/*
1346	 * XXX Can overrun, but we don't do signal queueing yet, anyway.
1347	 * XXX Relying on the clock interrupt is stupid.
1348	 */
1349	if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL || pt->pt_queued) {
1350		return;
1351	}
1352	TAILQ_INSERT_TAIL(&timer_queue, pt, pt_chain);
1353	pt->pt_queued = true;
1354	softint_schedule(timer_sih);
1355}
1356
1357void
1358timer_tick(lwp_t *l, bool user)
1359{
1360	struct ptimers *pts;
1361	struct ptimer *pt;
1362	proc_t *p;
1363
1364	p = l->l_proc;
1365	if (p->p_timers == NULL)
1366		return;
1367
1368	mutex_spin_enter(&timer_lock);
1369	if ((pts = l->l_proc->p_timers) != NULL) {
1370		/*
1371		 * Run current process's virtual and profile time, as needed.
1372		 */
1373		if (user && (pt = LIST_FIRST(&pts->pts_virtual)) != NULL)
1374			if (itimerdecr(pt, tick * 1000) == 0)
1375				itimerfire(pt);
1376		if ((pt = LIST_FIRST(&pts->pts_prof)) != NULL)
1377			if (itimerdecr(pt, tick * 1000) == 0)
1378				itimerfire(pt);
1379	}
1380	mutex_spin_exit(&timer_lock);
1381}
1382
1383static void
1384timer_intr(void *cookie)
1385{
1386	ksiginfo_t ksi;
1387	struct ptimer *pt;
1388	proc_t *p;
1389
1390	mutex_enter(proc_lock);
1391	mutex_spin_enter(&timer_lock);
1392	while ((pt = TAILQ_FIRST(&timer_queue)) != NULL) {
1393		TAILQ_REMOVE(&timer_queue, pt, pt_chain);
1394		KASSERT(pt->pt_queued);
1395		pt->pt_queued = false;
1396
1397		if (pt->pt_proc->p_timers == NULL) {
1398			/* Process is dying. */
1399			continue;
1400		}
1401		p = pt->pt_proc;
1402		if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL) {
1403			continue;
1404		}
1405		if (sigismember(&p->p_sigpend.sp_set, pt->pt_ev.sigev_signo)) {
1406			pt->pt_overruns++;
1407			continue;
1408		}
1409
1410		KSI_INIT(&ksi);
1411		ksi.ksi_signo = pt->pt_ev.sigev_signo;
1412		ksi.ksi_code = SI_TIMER;
1413		ksi.ksi_value = pt->pt_ev.sigev_value;
1414		pt->pt_poverruns = pt->pt_overruns;
1415		pt->pt_overruns = 0;
1416		mutex_spin_exit(&timer_lock);
1417		kpsignal(p, &ksi, NULL);
1418		mutex_spin_enter(&timer_lock);
1419	}
1420	mutex_spin_exit(&timer_lock);
1421	mutex_exit(proc_lock);
1422}
1423
1424/*
1425 * Check if the time will wrap if set to ts.
1426 *
1427 * ts - timespec describing the new time
1428 * delta - the delta between the current time and ts
1429 */
1430bool
1431time_wraps(struct timespec *ts, struct timespec *delta)
1432{
1433
1434	/*
1435	 * Don't allow the time to be set forward so far it
1436	 * will wrap and become negative, thus allowing an
1437	 * attacker to bypass the next check below.  The
1438	 * cutoff is 1 year before rollover occurs, so even
1439	 * if the attacker uses adjtime(2) to move the time
1440	 * past the cutoff, it will take a very long time
1441	 * to get to the wrap point.
1442	 */
1443	if ((ts->tv_sec > LLONG_MAX - 365*24*60*60) ||
1444	    (delta->tv_sec < 0 || delta->tv_nsec < 0))
1445		return true;
1446
1447	return false;
1448}
1449