kern_time.c revision 1.187
1/* $NetBSD: kern_time.c,v 1.187 2016/06/10 23:29:20 christos 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 1.187 2016/06/10 23:29:20 christos 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#define DELAYTIMER_MAX 32 101 102/* 103 * Initialize timekeeping. 104 */ 105void 106time_init(void) 107{ 108 109 pool_init(&ptimer_pool, sizeof(struct ptimer), 0, 0, 0, "ptimerpl", 110 &pool_allocator_nointr, IPL_NONE); 111 pool_init(&ptimers_pool, sizeof(struct ptimers), 0, 0, 0, "ptimerspl", 112 &pool_allocator_nointr, IPL_NONE); 113} 114 115void 116time_init2(void) 117{ 118 119 TAILQ_INIT(&timer_queue); 120 mutex_init(&timer_lock, MUTEX_DEFAULT, IPL_SCHED); 121 timer_sih = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE, 122 timer_intr, NULL); 123} 124 125/* Time of day and interval timer support. 126 * 127 * These routines provide the kernel entry points to get and set 128 * the time-of-day and per-process interval timers. Subroutines 129 * here provide support for adding and subtracting timeval structures 130 * and decrementing interval timers, optionally reloading the interval 131 * timers when they expire. 132 */ 133 134/* This function is used by clock_settime and settimeofday */ 135static int 136settime1(struct proc *p, const struct timespec *ts, bool check_kauth) 137{ 138 struct timespec delta, now; 139 int s; 140 141 /* WHAT DO WE DO ABOUT PENDING REAL-TIME TIMEOUTS??? */ 142 s = splclock(); 143 nanotime(&now); 144 timespecsub(ts, &now, &delta); 145 146 if (check_kauth && kauth_authorize_system(kauth_cred_get(), 147 KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_SYSTEM, __UNCONST(ts), 148 &delta, KAUTH_ARG(check_kauth ? false : true)) != 0) { 149 splx(s); 150 return (EPERM); 151 } 152 153#ifdef notyet 154 if ((delta.tv_sec < 86400) && securelevel > 0) { /* XXX elad - notyet */ 155 splx(s); 156 return (EPERM); 157 } 158#endif 159 160 tc_setclock(ts); 161 162 timespecadd(&boottime, &delta, &boottime); 163 164 resettodr(); 165 splx(s); 166 167 return (0); 168} 169 170int 171settime(struct proc *p, struct timespec *ts) 172{ 173 return (settime1(p, ts, true)); 174} 175 176/* ARGSUSED */ 177int 178sys___clock_gettime50(struct lwp *l, 179 const struct sys___clock_gettime50_args *uap, register_t *retval) 180{ 181 /* { 182 syscallarg(clockid_t) clock_id; 183 syscallarg(struct timespec *) tp; 184 } */ 185 int error; 186 struct timespec ats; 187 188 error = clock_gettime1(SCARG(uap, clock_id), &ats); 189 if (error != 0) 190 return error; 191 192 return copyout(&ats, SCARG(uap, tp), sizeof(ats)); 193} 194 195/* ARGSUSED */ 196int 197sys___clock_settime50(struct lwp *l, 198 const struct sys___clock_settime50_args *uap, register_t *retval) 199{ 200 /* { 201 syscallarg(clockid_t) clock_id; 202 syscallarg(const struct timespec *) tp; 203 } */ 204 int error; 205 struct timespec ats; 206 207 if ((error = copyin(SCARG(uap, tp), &ats, sizeof(ats))) != 0) 208 return error; 209 210 return clock_settime1(l->l_proc, SCARG(uap, clock_id), &ats, true); 211} 212 213 214int 215clock_settime1(struct proc *p, clockid_t clock_id, const struct timespec *tp, 216 bool check_kauth) 217{ 218 int error; 219 220 switch (clock_id) { 221 case CLOCK_REALTIME: 222 if ((error = settime1(p, tp, check_kauth)) != 0) 223 return (error); 224 break; 225 case CLOCK_MONOTONIC: 226 return (EINVAL); /* read-only clock */ 227 default: 228 return (EINVAL); 229 } 230 231 return 0; 232} 233 234int 235sys___clock_getres50(struct lwp *l, const struct sys___clock_getres50_args *uap, 236 register_t *retval) 237{ 238 /* { 239 syscallarg(clockid_t) clock_id; 240 syscallarg(struct timespec *) tp; 241 } */ 242 struct timespec ts; 243 int error; 244 245 if ((error = clock_getres1(SCARG(uap, clock_id), &ts)) != 0) 246 return error; 247 248 if (SCARG(uap, tp)) 249 error = copyout(&ts, SCARG(uap, tp), sizeof(ts)); 250 251 return error; 252} 253 254int 255clock_getres1(clockid_t clock_id, struct timespec *ts) 256{ 257 258 switch (clock_id) { 259 case CLOCK_REALTIME: 260 case CLOCK_MONOTONIC: 261 ts->tv_sec = 0; 262 if (tc_getfrequency() > 1000000000) 263 ts->tv_nsec = 1; 264 else 265 ts->tv_nsec = 1000000000 / tc_getfrequency(); 266 break; 267 default: 268 return EINVAL; 269 } 270 271 return 0; 272} 273 274/* ARGSUSED */ 275int 276sys___nanosleep50(struct lwp *l, const struct sys___nanosleep50_args *uap, 277 register_t *retval) 278{ 279 /* { 280 syscallarg(struct timespec *) rqtp; 281 syscallarg(struct timespec *) rmtp; 282 } */ 283 struct timespec rmt, rqt; 284 int error, error1; 285 286 error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec)); 287 if (error) 288 return (error); 289 290 error = nanosleep1(l, CLOCK_MONOTONIC, 0, &rqt, 291 SCARG(uap, rmtp) ? &rmt : NULL); 292 if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR)) 293 return error; 294 295 error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt)); 296 return error1 ? error1 : error; 297} 298 299/* ARGSUSED */ 300int 301sys_clock_nanosleep(struct lwp *l, const struct sys_clock_nanosleep_args *uap, 302 register_t *retval) 303{ 304 /* { 305 syscallarg(clockid_t) clock_id; 306 syscallarg(int) flags; 307 syscallarg(struct timespec *) rqtp; 308 syscallarg(struct timespec *) rmtp; 309 } */ 310 struct timespec rmt, rqt; 311 int error, error1; 312 313 error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec)); 314 if (error) 315 goto out; 316 317 error = nanosleep1(l, SCARG(uap, clock_id), SCARG(uap, flags), &rqt, 318 SCARG(uap, rmtp) ? &rmt : NULL); 319 if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR)) 320 goto out; 321 322 if ((error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt))) != 0) 323 error = error1; 324out: 325 *retval = error; 326 return 0; 327} 328 329int 330nanosleep1(struct lwp *l, clockid_t clock_id, int flags, struct timespec *rqt, 331 struct timespec *rmt) 332{ 333 struct timespec rmtstart; 334 int error, timo; 335 336 if ((error = ts2timo(clock_id, flags, rqt, &timo, &rmtstart)) != 0) { 337 if (error == ETIMEDOUT) { 338 error = 0; 339 if (rmt != NULL) 340 rmt->tv_sec = rmt->tv_nsec = 0; 341 } 342 return error; 343 } 344 345 /* 346 * Avoid inadvertently sleeping forever 347 */ 348 if (timo == 0) 349 timo = 1; 350again: 351 error = kpause("nanoslp", true, timo, NULL); 352 if (rmt != NULL || error == 0) { 353 struct timespec rmtend; 354 struct timespec t0; 355 struct timespec *t; 356 357 (void)clock_gettime1(clock_id, &rmtend); 358 t = (rmt != NULL) ? rmt : &t0; 359 if (flags & TIMER_ABSTIME) { 360 timespecsub(rqt, &rmtend, t); 361 } else { 362 timespecsub(&rmtend, &rmtstart, t); 363 timespecsub(rqt, t, t); 364 } 365 if (t->tv_sec < 0) 366 timespecclear(t); 367 if (error == 0) { 368 timo = tstohz(t); 369 if (timo > 0) 370 goto again; 371 } 372 } 373 374 if (error == ERESTART) 375 error = EINTR; 376 if (error == EWOULDBLOCK) 377 error = 0; 378 379 return error; 380} 381 382int 383sys_clock_getcpuclockid2(struct lwp *l, 384 const struct sys_clock_getcpuclockid2_args *uap, 385 register_t *retval) 386{ 387 /* { 388 syscallarg(idtype_t idtype; 389 syscallarg(id_t id); 390 syscallarg(clockid_t *)clock_id; 391 } */ 392 pid_t pid; 393 lwpid_t lid; 394 clockid_t clock_id; 395 id_t id = SCARG(uap, id); 396 397 switch (SCARG(uap, idtype)) { 398 case P_PID: 399 pid = id == 0 ? l->l_proc->p_pid : id; 400 clock_id = CLOCK_PROCESS_CPUTIME_ID | pid; 401 break; 402 case P_LWPID: 403 lid = id == 0 ? l->l_lid : id; 404 clock_id = CLOCK_THREAD_CPUTIME_ID | lid; 405 break; 406 default: 407 return EINVAL; 408 } 409 return copyout(&clock_id, SCARG(uap, clock_id), sizeof(clock_id)); 410} 411 412/* ARGSUSED */ 413int 414sys___gettimeofday50(struct lwp *l, const struct sys___gettimeofday50_args *uap, 415 register_t *retval) 416{ 417 /* { 418 syscallarg(struct timeval *) tp; 419 syscallarg(void *) tzp; really "struct timezone *"; 420 } */ 421 struct timeval atv; 422 int error = 0; 423 struct timezone tzfake; 424 425 if (SCARG(uap, tp)) { 426 microtime(&atv); 427 error = copyout(&atv, SCARG(uap, tp), sizeof(atv)); 428 if (error) 429 return (error); 430 } 431 if (SCARG(uap, tzp)) { 432 /* 433 * NetBSD has no kernel notion of time zone, so we just 434 * fake up a timezone struct and return it if demanded. 435 */ 436 tzfake.tz_minuteswest = 0; 437 tzfake.tz_dsttime = 0; 438 error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake)); 439 } 440 return (error); 441} 442 443/* ARGSUSED */ 444int 445sys___settimeofday50(struct lwp *l, const struct sys___settimeofday50_args *uap, 446 register_t *retval) 447{ 448 /* { 449 syscallarg(const struct timeval *) tv; 450 syscallarg(const void *) tzp; really "const struct timezone *"; 451 } */ 452 453 return settimeofday1(SCARG(uap, tv), true, SCARG(uap, tzp), l, true); 454} 455 456int 457settimeofday1(const struct timeval *utv, bool userspace, 458 const void *utzp, struct lwp *l, bool check_kauth) 459{ 460 struct timeval atv; 461 struct timespec ts; 462 int error; 463 464 /* Verify all parameters before changing time. */ 465 466 /* 467 * NetBSD has no kernel notion of time zone, and only an 468 * obsolete program would try to set it, so we log a warning. 469 */ 470 if (utzp) 471 log(LOG_WARNING, "pid %d attempted to set the " 472 "(obsolete) kernel time zone\n", l->l_proc->p_pid); 473 474 if (utv == NULL) 475 return 0; 476 477 if (userspace) { 478 if ((error = copyin(utv, &atv, sizeof(atv))) != 0) 479 return error; 480 utv = &atv; 481 } 482 483 TIMEVAL_TO_TIMESPEC(utv, &ts); 484 return settime1(l->l_proc, &ts, check_kauth); 485} 486 487int time_adjusted; /* set if an adjustment is made */ 488 489/* ARGSUSED */ 490int 491sys___adjtime50(struct lwp *l, const struct sys___adjtime50_args *uap, 492 register_t *retval) 493{ 494 /* { 495 syscallarg(const struct timeval *) delta; 496 syscallarg(struct timeval *) olddelta; 497 } */ 498 int error; 499 struct timeval atv, oldatv; 500 501 if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_TIME, 502 KAUTH_REQ_SYSTEM_TIME_ADJTIME, NULL, NULL, NULL)) != 0) 503 return error; 504 505 if (SCARG(uap, delta)) { 506 error = copyin(SCARG(uap, delta), &atv, 507 sizeof(*SCARG(uap, delta))); 508 if (error) 509 return (error); 510 } 511 adjtime1(SCARG(uap, delta) ? &atv : NULL, 512 SCARG(uap, olddelta) ? &oldatv : NULL, l->l_proc); 513 if (SCARG(uap, olddelta)) 514 error = copyout(&oldatv, SCARG(uap, olddelta), 515 sizeof(*SCARG(uap, olddelta))); 516 return error; 517} 518 519void 520adjtime1(const struct timeval *delta, struct timeval *olddelta, struct proc *p) 521{ 522 extern int64_t time_adjtime; /* in kern_ntptime.c */ 523 524 if (olddelta) { 525 mutex_spin_enter(&timecounter_lock); 526 olddelta->tv_sec = time_adjtime / 1000000; 527 olddelta->tv_usec = time_adjtime % 1000000; 528 if (olddelta->tv_usec < 0) { 529 olddelta->tv_usec += 1000000; 530 olddelta->tv_sec--; 531 } 532 mutex_spin_exit(&timecounter_lock); 533 } 534 535 if (delta) { 536 mutex_spin_enter(&timecounter_lock); 537 time_adjtime = delta->tv_sec * 1000000 + delta->tv_usec; 538 539 if (time_adjtime) { 540 /* We need to save the system time during shutdown */ 541 time_adjusted |= 1; 542 } 543 mutex_spin_exit(&timecounter_lock); 544 } 545} 546 547/* 548 * Interval timer support. Both the BSD getitimer() family and the POSIX 549 * timer_*() family of routines are supported. 550 * 551 * All timers are kept in an array pointed to by p_timers, which is 552 * allocated on demand - many processes don't use timers at all. The 553 * first four elements in this array are reserved for the BSD timers: 554 * element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, element 555 * 2 is ITIMER_PROF, and element 3 is ITIMER_MONOTONIC. The rest may be 556 * allocated by the timer_create() syscall. 557 * 558 * Realtime timers are kept in the ptimer structure as an absolute 559 * time; virtual time timers are kept as a linked list of deltas. 560 * Virtual time timers are processed in the hardclock() routine of 561 * kern_clock.c. The real time timer is processed by a callout 562 * routine, called from the softclock() routine. Since a callout may 563 * be delayed in real time due to interrupt processing in the system, 564 * it is possible for the real time timeout routine (realtimeexpire, 565 * given below), to be delayed in real time past when it is supposed 566 * to occur. It does not suffice, therefore, to reload the real timer 567 * .it_value from the real time timers .it_interval. Rather, we 568 * compute the next time in absolute time the timer should go off. */ 569 570/* Allocate a POSIX realtime timer. */ 571int 572sys_timer_create(struct lwp *l, const struct sys_timer_create_args *uap, 573 register_t *retval) 574{ 575 /* { 576 syscallarg(clockid_t) clock_id; 577 syscallarg(struct sigevent *) evp; 578 syscallarg(timer_t *) timerid; 579 } */ 580 581 return timer_create1(SCARG(uap, timerid), SCARG(uap, clock_id), 582 SCARG(uap, evp), copyin, l); 583} 584 585int 586timer_create1(timer_t *tid, clockid_t id, struct sigevent *evp, 587 copyin_t fetch_event, struct lwp *l) 588{ 589 int error; 590 timer_t timerid; 591 struct ptimers *pts; 592 struct ptimer *pt; 593 struct proc *p; 594 595 p = l->l_proc; 596 597 if ((u_int)id > CLOCK_MONOTONIC) 598 return (EINVAL); 599 600 if ((pts = p->p_timers) == NULL) 601 pts = timers_alloc(p); 602 603 pt = pool_get(&ptimer_pool, PR_WAITOK); 604 if (evp != NULL) { 605 if (((error = 606 (*fetch_event)(evp, &pt->pt_ev, sizeof(pt->pt_ev))) != 0) || 607 ((pt->pt_ev.sigev_notify < SIGEV_NONE) || 608 (pt->pt_ev.sigev_notify > SIGEV_SA)) || 609 (pt->pt_ev.sigev_notify == SIGEV_SIGNAL && 610 (pt->pt_ev.sigev_signo <= 0 || 611 pt->pt_ev.sigev_signo >= NSIG))) { 612 pool_put(&ptimer_pool, pt); 613 return (error ? error : EINVAL); 614 } 615 } 616 617 /* Find a free timer slot, skipping those reserved for setitimer(). */ 618 mutex_spin_enter(&timer_lock); 619 for (timerid = TIMER_MIN; timerid < TIMER_MAX; timerid++) 620 if (pts->pts_timers[timerid] == NULL) 621 break; 622 if (timerid == TIMER_MAX) { 623 mutex_spin_exit(&timer_lock); 624 pool_put(&ptimer_pool, pt); 625 return EAGAIN; 626 } 627 if (evp == NULL) { 628 pt->pt_ev.sigev_notify = SIGEV_SIGNAL; 629 switch (id) { 630 case CLOCK_REALTIME: 631 case CLOCK_MONOTONIC: 632 pt->pt_ev.sigev_signo = SIGALRM; 633 break; 634 case CLOCK_VIRTUAL: 635 pt->pt_ev.sigev_signo = SIGVTALRM; 636 break; 637 case CLOCK_PROF: 638 pt->pt_ev.sigev_signo = SIGPROF; 639 break; 640 } 641 pt->pt_ev.sigev_value.sival_int = timerid; 642 } 643 pt->pt_info.ksi_signo = pt->pt_ev.sigev_signo; 644 pt->pt_info.ksi_errno = 0; 645 pt->pt_info.ksi_code = 0; 646 pt->pt_info.ksi_pid = p->p_pid; 647 pt->pt_info.ksi_uid = kauth_cred_getuid(l->l_cred); 648 pt->pt_info.ksi_value = pt->pt_ev.sigev_value; 649 pt->pt_type = id; 650 pt->pt_proc = p; 651 pt->pt_overruns = 0; 652 pt->pt_poverruns = 0; 653 pt->pt_entry = timerid; 654 pt->pt_queued = false; 655 timespecclear(&pt->pt_time.it_value); 656 if (!CLOCK_VIRTUAL_P(id)) 657 callout_init(&pt->pt_ch, CALLOUT_MPSAFE); 658 else 659 pt->pt_active = 0; 660 661 pts->pts_timers[timerid] = pt; 662 mutex_spin_exit(&timer_lock); 663 664 return copyout(&timerid, tid, sizeof(timerid)); 665} 666 667/* Delete a POSIX realtime timer */ 668int 669sys_timer_delete(struct lwp *l, const struct sys_timer_delete_args *uap, 670 register_t *retval) 671{ 672 /* { 673 syscallarg(timer_t) timerid; 674 } */ 675 struct proc *p = l->l_proc; 676 timer_t timerid; 677 struct ptimers *pts; 678 struct ptimer *pt, *ptn; 679 680 timerid = SCARG(uap, timerid); 681 pts = p->p_timers; 682 683 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 684 return (EINVAL); 685 686 mutex_spin_enter(&timer_lock); 687 if ((pt = pts->pts_timers[timerid]) == NULL) { 688 mutex_spin_exit(&timer_lock); 689 return (EINVAL); 690 } 691 if (CLOCK_VIRTUAL_P(pt->pt_type)) { 692 if (pt->pt_active) { 693 ptn = LIST_NEXT(pt, pt_list); 694 LIST_REMOVE(pt, pt_list); 695 for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list)) 696 timespecadd(&pt->pt_time.it_value, 697 &ptn->pt_time.it_value, 698 &ptn->pt_time.it_value); 699 pt->pt_active = 0; 700 } 701 } 702 itimerfree(pts, timerid); 703 704 return (0); 705} 706 707/* 708 * Set up the given timer. The value in pt->pt_time.it_value is taken 709 * to be an absolute time for CLOCK_REALTIME/CLOCK_MONOTONIC timers and 710 * a relative time for CLOCK_VIRTUAL/CLOCK_PROF timers. 711 */ 712void 713timer_settime(struct ptimer *pt) 714{ 715 struct ptimer *ptn, *pptn; 716 struct ptlist *ptl; 717 718 KASSERT(mutex_owned(&timer_lock)); 719 720 if (!CLOCK_VIRTUAL_P(pt->pt_type)) { 721 callout_halt(&pt->pt_ch, &timer_lock); 722 if (timespecisset(&pt->pt_time.it_value)) { 723 /* 724 * Don't need to check tshzto() return value, here. 725 * callout_reset() does it for us. 726 */ 727 callout_reset(&pt->pt_ch, 728 pt->pt_type == CLOCK_MONOTONIC ? 729 tshztoup(&pt->pt_time.it_value) : 730 tshzto(&pt->pt_time.it_value), 731 realtimerexpire, pt); 732 } 733 } else { 734 if (pt->pt_active) { 735 ptn = LIST_NEXT(pt, pt_list); 736 LIST_REMOVE(pt, pt_list); 737 for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list)) 738 timespecadd(&pt->pt_time.it_value, 739 &ptn->pt_time.it_value, 740 &ptn->pt_time.it_value); 741 } 742 if (timespecisset(&pt->pt_time.it_value)) { 743 if (pt->pt_type == CLOCK_VIRTUAL) 744 ptl = &pt->pt_proc->p_timers->pts_virtual; 745 else 746 ptl = &pt->pt_proc->p_timers->pts_prof; 747 748 for (ptn = LIST_FIRST(ptl), pptn = NULL; 749 ptn && timespeccmp(&pt->pt_time.it_value, 750 &ptn->pt_time.it_value, >); 751 pptn = ptn, ptn = LIST_NEXT(ptn, pt_list)) 752 timespecsub(&pt->pt_time.it_value, 753 &ptn->pt_time.it_value, 754 &pt->pt_time.it_value); 755 756 if (pptn) 757 LIST_INSERT_AFTER(pptn, pt, pt_list); 758 else 759 LIST_INSERT_HEAD(ptl, pt, pt_list); 760 761 for ( ; ptn ; ptn = LIST_NEXT(ptn, pt_list)) 762 timespecsub(&ptn->pt_time.it_value, 763 &pt->pt_time.it_value, 764 &ptn->pt_time.it_value); 765 766 pt->pt_active = 1; 767 } else 768 pt->pt_active = 0; 769 } 770} 771 772void 773timer_gettime(struct ptimer *pt, struct itimerspec *aits) 774{ 775 struct timespec now; 776 struct ptimer *ptn; 777 778 KASSERT(mutex_owned(&timer_lock)); 779 780 *aits = pt->pt_time; 781 if (!CLOCK_VIRTUAL_P(pt->pt_type)) { 782 /* 783 * Convert from absolute to relative time in .it_value 784 * part of real time timer. If time for real time 785 * timer has passed return 0, else return difference 786 * between current time and time for the timer to go 787 * off. 788 */ 789 if (timespecisset(&aits->it_value)) { 790 if (pt->pt_type == CLOCK_REALTIME) { 791 getnanotime(&now); 792 } else { /* CLOCK_MONOTONIC */ 793 getnanouptime(&now); 794 } 795 if (timespeccmp(&aits->it_value, &now, <)) 796 timespecclear(&aits->it_value); 797 else 798 timespecsub(&aits->it_value, &now, 799 &aits->it_value); 800 } 801 } else if (pt->pt_active) { 802 if (pt->pt_type == CLOCK_VIRTUAL) 803 ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_virtual); 804 else 805 ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_prof); 806 for ( ; ptn && ptn != pt; ptn = LIST_NEXT(ptn, pt_list)) 807 timespecadd(&aits->it_value, 808 &ptn->pt_time.it_value, &aits->it_value); 809 KASSERT(ptn != NULL); /* pt should be findable on the list */ 810 } else 811 timespecclear(&aits->it_value); 812} 813 814 815 816/* Set and arm a POSIX realtime timer */ 817int 818sys___timer_settime50(struct lwp *l, 819 const struct sys___timer_settime50_args *uap, 820 register_t *retval) 821{ 822 /* { 823 syscallarg(timer_t) timerid; 824 syscallarg(int) flags; 825 syscallarg(const struct itimerspec *) value; 826 syscallarg(struct itimerspec *) ovalue; 827 } */ 828 int error; 829 struct itimerspec value, ovalue, *ovp = NULL; 830 831 if ((error = copyin(SCARG(uap, value), &value, 832 sizeof(struct itimerspec))) != 0) 833 return (error); 834 835 if (SCARG(uap, ovalue)) 836 ovp = &ovalue; 837 838 if ((error = dotimer_settime(SCARG(uap, timerid), &value, ovp, 839 SCARG(uap, flags), l->l_proc)) != 0) 840 return error; 841 842 if (ovp) 843 return copyout(&ovalue, SCARG(uap, ovalue), 844 sizeof(struct itimerspec)); 845 return 0; 846} 847 848int 849dotimer_settime(int timerid, struct itimerspec *value, 850 struct itimerspec *ovalue, int flags, struct proc *p) 851{ 852 struct timespec now; 853 struct itimerspec val, oval; 854 struct ptimers *pts; 855 struct ptimer *pt; 856 int error; 857 858 pts = p->p_timers; 859 860 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 861 return EINVAL; 862 val = *value; 863 if ((error = itimespecfix(&val.it_value)) != 0 || 864 (error = itimespecfix(&val.it_interval)) != 0) 865 return error; 866 867 mutex_spin_enter(&timer_lock); 868 if ((pt = pts->pts_timers[timerid]) == NULL) { 869 mutex_spin_exit(&timer_lock); 870 return EINVAL; 871 } 872 873 oval = pt->pt_time; 874 pt->pt_time = val; 875 876 /* 877 * If we've been passed a relative time for a realtime timer, 878 * convert it to absolute; if an absolute time for a virtual 879 * timer, convert it to relative and make sure we don't set it 880 * to zero, which would cancel the timer, or let it go 881 * negative, which would confuse the comparison tests. 882 */ 883 if (timespecisset(&pt->pt_time.it_value)) { 884 if (!CLOCK_VIRTUAL_P(pt->pt_type)) { 885 if ((flags & TIMER_ABSTIME) == 0) { 886 if (pt->pt_type == CLOCK_REALTIME) { 887 getnanotime(&now); 888 } else { /* CLOCK_MONOTONIC */ 889 getnanouptime(&now); 890 } 891 timespecadd(&pt->pt_time.it_value, &now, 892 &pt->pt_time.it_value); 893 } 894 } else { 895 if ((flags & TIMER_ABSTIME) != 0) { 896 getnanotime(&now); 897 timespecsub(&pt->pt_time.it_value, &now, 898 &pt->pt_time.it_value); 899 if (!timespecisset(&pt->pt_time.it_value) || 900 pt->pt_time.it_value.tv_sec < 0) { 901 pt->pt_time.it_value.tv_sec = 0; 902 pt->pt_time.it_value.tv_nsec = 1; 903 } 904 } 905 } 906 } 907 908 timer_settime(pt); 909 mutex_spin_exit(&timer_lock); 910 911 if (ovalue) 912 *ovalue = oval; 913 914 return (0); 915} 916 917/* Return the time remaining until a POSIX timer fires. */ 918int 919sys___timer_gettime50(struct lwp *l, 920 const struct sys___timer_gettime50_args *uap, register_t *retval) 921{ 922 /* { 923 syscallarg(timer_t) timerid; 924 syscallarg(struct itimerspec *) value; 925 } */ 926 struct itimerspec its; 927 int error; 928 929 if ((error = dotimer_gettime(SCARG(uap, timerid), l->l_proc, 930 &its)) != 0) 931 return error; 932 933 return copyout(&its, SCARG(uap, value), sizeof(its)); 934} 935 936int 937dotimer_gettime(int timerid, struct proc *p, struct itimerspec *its) 938{ 939 struct ptimer *pt; 940 struct ptimers *pts; 941 942 pts = p->p_timers; 943 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 944 return (EINVAL); 945 mutex_spin_enter(&timer_lock); 946 if ((pt = pts->pts_timers[timerid]) == NULL) { 947 mutex_spin_exit(&timer_lock); 948 return (EINVAL); 949 } 950 timer_gettime(pt, its); 951 mutex_spin_exit(&timer_lock); 952 953 return 0; 954} 955 956/* 957 * Return the count of the number of times a periodic timer expired 958 * while a notification was already pending. The counter is reset when 959 * a timer expires and a notification can be posted. 960 */ 961int 962sys_timer_getoverrun(struct lwp *l, const struct sys_timer_getoverrun_args *uap, 963 register_t *retval) 964{ 965 /* { 966 syscallarg(timer_t) timerid; 967 } */ 968 struct proc *p = l->l_proc; 969 struct ptimers *pts; 970 int timerid; 971 struct ptimer *pt; 972 973 timerid = SCARG(uap, timerid); 974 975 pts = p->p_timers; 976 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 977 return (EINVAL); 978 mutex_spin_enter(&timer_lock); 979 if ((pt = pts->pts_timers[timerid]) == NULL) { 980 mutex_spin_exit(&timer_lock); 981 return (EINVAL); 982 } 983 *retval = pt->pt_poverruns; 984 if (*retval >= DELAYTIMER_MAX) 985 *retval = DELAYTIMER_MAX; 986 mutex_spin_exit(&timer_lock); 987 988 return (0); 989} 990 991/* 992 * Real interval timer expired: 993 * send process whose timer expired an alarm signal. 994 * If time is not set up to reload, then just return. 995 * Else compute next time timer should go off which is > current time. 996 * This is where delay in processing this timeout causes multiple 997 * SIGALRM calls to be compressed into one. 998 */ 999void 1000realtimerexpire(void *arg) 1001{ 1002 uint64_t last_val, next_val, interval, now_ns; 1003 struct timespec now, next; 1004 struct ptimer *pt; 1005 int backwards; 1006 1007 pt = arg; 1008 1009 mutex_spin_enter(&timer_lock); 1010 itimerfire(pt); 1011 1012 if (!timespecisset(&pt->pt_time.it_interval)) { 1013 timespecclear(&pt->pt_time.it_value); 1014 mutex_spin_exit(&timer_lock); 1015 return; 1016 } 1017 1018 if (pt->pt_type == CLOCK_MONOTONIC) { 1019 getnanouptime(&now); 1020 } else { 1021 getnanotime(&now); 1022 } 1023 backwards = (timespeccmp(&pt->pt_time.it_value, &now, >)); 1024 timespecadd(&pt->pt_time.it_value, &pt->pt_time.it_interval, &next); 1025 /* Handle the easy case of non-overflown timers first. */ 1026 if (!backwards && timespeccmp(&next, &now, >)) { 1027 pt->pt_time.it_value = next; 1028 } else { 1029 now_ns = timespec2ns(&now); 1030 last_val = timespec2ns(&pt->pt_time.it_value); 1031 interval = timespec2ns(&pt->pt_time.it_interval); 1032 1033 next_val = now_ns + 1034 (now_ns - last_val + interval - 1) % interval; 1035 1036 if (backwards) 1037 next_val += interval; 1038 else 1039 pt->pt_overruns += (now_ns - last_val) / interval; 1040 1041 pt->pt_time.it_value.tv_sec = next_val / 1000000000; 1042 pt->pt_time.it_value.tv_nsec = next_val % 1000000000; 1043 } 1044 1045 /* 1046 * Don't need to check tshzto() return value, here. 1047 * callout_reset() does it for us. 1048 */ 1049 callout_reset(&pt->pt_ch, pt->pt_type == CLOCK_MONOTONIC ? 1050 tshztoup(&pt->pt_time.it_value) : tshzto(&pt->pt_time.it_value), 1051 realtimerexpire, pt); 1052 mutex_spin_exit(&timer_lock); 1053} 1054 1055/* BSD routine to get the value of an interval timer. */ 1056/* ARGSUSED */ 1057int 1058sys___getitimer50(struct lwp *l, const struct sys___getitimer50_args *uap, 1059 register_t *retval) 1060{ 1061 /* { 1062 syscallarg(int) which; 1063 syscallarg(struct itimerval *) itv; 1064 } */ 1065 struct proc *p = l->l_proc; 1066 struct itimerval aitv; 1067 int error; 1068 1069 error = dogetitimer(p, SCARG(uap, which), &aitv); 1070 if (error) 1071 return error; 1072 return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval))); 1073} 1074 1075int 1076dogetitimer(struct proc *p, int which, struct itimerval *itvp) 1077{ 1078 struct ptimers *pts; 1079 struct ptimer *pt; 1080 struct itimerspec its; 1081 1082 if ((u_int)which > ITIMER_MONOTONIC) 1083 return (EINVAL); 1084 1085 mutex_spin_enter(&timer_lock); 1086 pts = p->p_timers; 1087 if (pts == NULL || (pt = pts->pts_timers[which]) == NULL) { 1088 timerclear(&itvp->it_value); 1089 timerclear(&itvp->it_interval); 1090 } else { 1091 timer_gettime(pt, &its); 1092 TIMESPEC_TO_TIMEVAL(&itvp->it_value, &its.it_value); 1093 TIMESPEC_TO_TIMEVAL(&itvp->it_interval, &its.it_interval); 1094 } 1095 mutex_spin_exit(&timer_lock); 1096 1097 return 0; 1098} 1099 1100/* BSD routine to set/arm an interval timer. */ 1101/* ARGSUSED */ 1102int 1103sys___setitimer50(struct lwp *l, const struct sys___setitimer50_args *uap, 1104 register_t *retval) 1105{ 1106 /* { 1107 syscallarg(int) which; 1108 syscallarg(const struct itimerval *) itv; 1109 syscallarg(struct itimerval *) oitv; 1110 } */ 1111 struct proc *p = l->l_proc; 1112 int which = SCARG(uap, which); 1113 struct sys___getitimer50_args getargs; 1114 const struct itimerval *itvp; 1115 struct itimerval aitv; 1116 int error; 1117 1118 if ((u_int)which > ITIMER_MONOTONIC) 1119 return (EINVAL); 1120 itvp = SCARG(uap, itv); 1121 if (itvp && 1122 (error = copyin(itvp, &aitv, sizeof(struct itimerval))) != 0) 1123 return (error); 1124 if (SCARG(uap, oitv) != NULL) { 1125 SCARG(&getargs, which) = which; 1126 SCARG(&getargs, itv) = SCARG(uap, oitv); 1127 if ((error = sys___getitimer50(l, &getargs, retval)) != 0) 1128 return (error); 1129 } 1130 if (itvp == 0) 1131 return (0); 1132 1133 return dosetitimer(p, which, &aitv); 1134} 1135 1136int 1137dosetitimer(struct proc *p, int which, struct itimerval *itvp) 1138{ 1139 struct timespec now; 1140 struct ptimers *pts; 1141 struct ptimer *pt, *spare; 1142 1143 KASSERT((u_int)which <= CLOCK_MONOTONIC); 1144 if (itimerfix(&itvp->it_value) || itimerfix(&itvp->it_interval)) 1145 return (EINVAL); 1146 1147 /* 1148 * Don't bother allocating data structures if the process just 1149 * wants to clear the timer. 1150 */ 1151 spare = NULL; 1152 pts = p->p_timers; 1153 retry: 1154 if (!timerisset(&itvp->it_value) && (pts == NULL || 1155 pts->pts_timers[which] == NULL)) 1156 return (0); 1157 if (pts == NULL) 1158 pts = timers_alloc(p); 1159 mutex_spin_enter(&timer_lock); 1160 pt = pts->pts_timers[which]; 1161 if (pt == NULL) { 1162 if (spare == NULL) { 1163 mutex_spin_exit(&timer_lock); 1164 spare = pool_get(&ptimer_pool, PR_WAITOK); 1165 goto retry; 1166 } 1167 pt = spare; 1168 spare = NULL; 1169 pt->pt_ev.sigev_notify = SIGEV_SIGNAL; 1170 pt->pt_ev.sigev_value.sival_int = which; 1171 pt->pt_overruns = 0; 1172 pt->pt_proc = p; 1173 pt->pt_type = which; 1174 pt->pt_entry = which; 1175 pt->pt_queued = false; 1176 if (pt->pt_type == CLOCK_REALTIME) 1177 callout_init(&pt->pt_ch, CALLOUT_MPSAFE); 1178 else 1179 pt->pt_active = 0; 1180 1181 switch (which) { 1182 case ITIMER_REAL: 1183 case ITIMER_MONOTONIC: 1184 pt->pt_ev.sigev_signo = SIGALRM; 1185 break; 1186 case ITIMER_VIRTUAL: 1187 pt->pt_ev.sigev_signo = SIGVTALRM; 1188 break; 1189 case ITIMER_PROF: 1190 pt->pt_ev.sigev_signo = SIGPROF; 1191 break; 1192 } 1193 pts->pts_timers[which] = pt; 1194 } 1195 1196 TIMEVAL_TO_TIMESPEC(&itvp->it_value, &pt->pt_time.it_value); 1197 TIMEVAL_TO_TIMESPEC(&itvp->it_interval, &pt->pt_time.it_interval); 1198 1199 if (timespecisset(&pt->pt_time.it_value)) { 1200 /* Convert to absolute time */ 1201 /* XXX need to wrap in splclock for timecounters case? */ 1202 switch (which) { 1203 case ITIMER_REAL: 1204 getnanotime(&now); 1205 timespecadd(&pt->pt_time.it_value, &now, 1206 &pt->pt_time.it_value); 1207 break; 1208 case ITIMER_MONOTONIC: 1209 getnanouptime(&now); 1210 timespecadd(&pt->pt_time.it_value, &now, 1211 &pt->pt_time.it_value); 1212 break; 1213 default: 1214 break; 1215 } 1216 } 1217 timer_settime(pt); 1218 mutex_spin_exit(&timer_lock); 1219 if (spare != NULL) 1220 pool_put(&ptimer_pool, spare); 1221 1222 return (0); 1223} 1224 1225/* Utility routines to manage the array of pointers to timers. */ 1226struct ptimers * 1227timers_alloc(struct proc *p) 1228{ 1229 struct ptimers *pts; 1230 int i; 1231 1232 pts = pool_get(&ptimers_pool, PR_WAITOK); 1233 LIST_INIT(&pts->pts_virtual); 1234 LIST_INIT(&pts->pts_prof); 1235 for (i = 0; i < TIMER_MAX; i++) 1236 pts->pts_timers[i] = NULL; 1237 mutex_spin_enter(&timer_lock); 1238 if (p->p_timers == NULL) { 1239 p->p_timers = pts; 1240 mutex_spin_exit(&timer_lock); 1241 return pts; 1242 } 1243 mutex_spin_exit(&timer_lock); 1244 pool_put(&ptimers_pool, pts); 1245 return p->p_timers; 1246} 1247 1248/* 1249 * Clean up the per-process timers. If "which" is set to TIMERS_ALL, 1250 * then clean up all timers and free all the data structures. If 1251 * "which" is set to TIMERS_POSIX, only clean up the timers allocated 1252 * by timer_create(), not the BSD setitimer() timers, and only free the 1253 * structure if none of those remain. 1254 */ 1255void 1256timers_free(struct proc *p, int which) 1257{ 1258 struct ptimers *pts; 1259 struct ptimer *ptn; 1260 struct timespec ts; 1261 int i; 1262 1263 if (p->p_timers == NULL) 1264 return; 1265 1266 pts = p->p_timers; 1267 mutex_spin_enter(&timer_lock); 1268 if (which == TIMERS_ALL) { 1269 p->p_timers = NULL; 1270 i = 0; 1271 } else { 1272 timespecclear(&ts); 1273 for (ptn = LIST_FIRST(&pts->pts_virtual); 1274 ptn && ptn != pts->pts_timers[ITIMER_VIRTUAL]; 1275 ptn = LIST_NEXT(ptn, pt_list)) { 1276 KASSERT(ptn->pt_type == CLOCK_VIRTUAL); 1277 timespecadd(&ts, &ptn->pt_time.it_value, &ts); 1278 } 1279 LIST_FIRST(&pts->pts_virtual) = NULL; 1280 if (ptn) { 1281 KASSERT(ptn->pt_type == CLOCK_VIRTUAL); 1282 timespecadd(&ts, &ptn->pt_time.it_value, 1283 &ptn->pt_time.it_value); 1284 LIST_INSERT_HEAD(&pts->pts_virtual, ptn, pt_list); 1285 } 1286 timespecclear(&ts); 1287 for (ptn = LIST_FIRST(&pts->pts_prof); 1288 ptn && ptn != pts->pts_timers[ITIMER_PROF]; 1289 ptn = LIST_NEXT(ptn, pt_list)) { 1290 KASSERT(ptn->pt_type == CLOCK_PROF); 1291 timespecadd(&ts, &ptn->pt_time.it_value, &ts); 1292 } 1293 LIST_FIRST(&pts->pts_prof) = NULL; 1294 if (ptn) { 1295 KASSERT(ptn->pt_type == CLOCK_PROF); 1296 timespecadd(&ts, &ptn->pt_time.it_value, 1297 &ptn->pt_time.it_value); 1298 LIST_INSERT_HEAD(&pts->pts_prof, ptn, pt_list); 1299 } 1300 i = TIMER_MIN; 1301 } 1302 for ( ; i < TIMER_MAX; i++) { 1303 if (pts->pts_timers[i] != NULL) { 1304 itimerfree(pts, i); 1305 mutex_spin_enter(&timer_lock); 1306 } 1307 } 1308 if (pts->pts_timers[0] == NULL && pts->pts_timers[1] == NULL && 1309 pts->pts_timers[2] == NULL && pts->pts_timers[3] == NULL) { 1310 p->p_timers = NULL; 1311 mutex_spin_exit(&timer_lock); 1312 pool_put(&ptimers_pool, pts); 1313 } else 1314 mutex_spin_exit(&timer_lock); 1315} 1316 1317static void 1318itimerfree(struct ptimers *pts, int index) 1319{ 1320 struct ptimer *pt; 1321 1322 KASSERT(mutex_owned(&timer_lock)); 1323 1324 pt = pts->pts_timers[index]; 1325 pts->pts_timers[index] = NULL; 1326 if (!CLOCK_VIRTUAL_P(pt->pt_type)) 1327 callout_halt(&pt->pt_ch, &timer_lock); 1328 if (pt->pt_queued) 1329 TAILQ_REMOVE(&timer_queue, pt, pt_chain); 1330 mutex_spin_exit(&timer_lock); 1331 if (!CLOCK_VIRTUAL_P(pt->pt_type)) 1332 callout_destroy(&pt->pt_ch); 1333 pool_put(&ptimer_pool, pt); 1334} 1335 1336/* 1337 * Decrement an interval timer by a specified number 1338 * of nanoseconds, which must be less than a second, 1339 * i.e. < 1000000000. If the timer expires, then reload 1340 * it. In this case, carry over (nsec - old value) to 1341 * reduce the value reloaded into the timer so that 1342 * the timer does not drift. This routine assumes 1343 * that it is called in a context where the timers 1344 * on which it is operating cannot change in value. 1345 */ 1346static int 1347itimerdecr(struct ptimer *pt, int nsec) 1348{ 1349 struct itimerspec *itp; 1350 1351 KASSERT(mutex_owned(&timer_lock)); 1352 KASSERT(CLOCK_VIRTUAL_P(pt->pt_type)); 1353 1354 itp = &pt->pt_time; 1355 if (itp->it_value.tv_nsec < nsec) { 1356 if (itp->it_value.tv_sec == 0) { 1357 /* expired, and already in next interval */ 1358 nsec -= itp->it_value.tv_nsec; 1359 goto expire; 1360 } 1361 itp->it_value.tv_nsec += 1000000000; 1362 itp->it_value.tv_sec--; 1363 } 1364 itp->it_value.tv_nsec -= nsec; 1365 nsec = 0; 1366 if (timespecisset(&itp->it_value)) 1367 return (1); 1368 /* expired, exactly at end of interval */ 1369expire: 1370 if (timespecisset(&itp->it_interval)) { 1371 itp->it_value = itp->it_interval; 1372 itp->it_value.tv_nsec -= nsec; 1373 if (itp->it_value.tv_nsec < 0) { 1374 itp->it_value.tv_nsec += 1000000000; 1375 itp->it_value.tv_sec--; 1376 } 1377 timer_settime(pt); 1378 } else 1379 itp->it_value.tv_nsec = 0; /* sec is already 0 */ 1380 return (0); 1381} 1382 1383static void 1384itimerfire(struct ptimer *pt) 1385{ 1386 1387 KASSERT(mutex_owned(&timer_lock)); 1388 1389 /* 1390 * XXX Can overrun, but we don't do signal queueing yet, anyway. 1391 * XXX Relying on the clock interrupt is stupid. 1392 */ 1393 if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL || pt->pt_queued) { 1394 return; 1395 } 1396 TAILQ_INSERT_TAIL(&timer_queue, pt, pt_chain); 1397 pt->pt_queued = true; 1398 softint_schedule(timer_sih); 1399} 1400 1401void 1402timer_tick(lwp_t *l, bool user) 1403{ 1404 struct ptimers *pts; 1405 struct ptimer *pt; 1406 proc_t *p; 1407 1408 p = l->l_proc; 1409 if (p->p_timers == NULL) 1410 return; 1411 1412 mutex_spin_enter(&timer_lock); 1413 if ((pts = l->l_proc->p_timers) != NULL) { 1414 /* 1415 * Run current process's virtual and profile time, as needed. 1416 */ 1417 if (user && (pt = LIST_FIRST(&pts->pts_virtual)) != NULL) 1418 if (itimerdecr(pt, tick * 1000) == 0) 1419 itimerfire(pt); 1420 if ((pt = LIST_FIRST(&pts->pts_prof)) != NULL) 1421 if (itimerdecr(pt, tick * 1000) == 0) 1422 itimerfire(pt); 1423 } 1424 mutex_spin_exit(&timer_lock); 1425} 1426 1427static void 1428timer_intr(void *cookie) 1429{ 1430 ksiginfo_t ksi; 1431 struct ptimer *pt; 1432 proc_t *p; 1433 1434 mutex_enter(proc_lock); 1435 mutex_spin_enter(&timer_lock); 1436 while ((pt = TAILQ_FIRST(&timer_queue)) != NULL) { 1437 TAILQ_REMOVE(&timer_queue, pt, pt_chain); 1438 KASSERT(pt->pt_queued); 1439 pt->pt_queued = false; 1440 1441 if (pt->pt_proc->p_timers == NULL) { 1442 /* Process is dying. */ 1443 continue; 1444 } 1445 p = pt->pt_proc; 1446 if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL) { 1447 continue; 1448 } 1449 if (sigismember(&p->p_sigpend.sp_set, pt->pt_ev.sigev_signo)) { 1450 pt->pt_overruns++; 1451 continue; 1452 } 1453 1454 KSI_INIT(&ksi); 1455 ksi.ksi_signo = pt->pt_ev.sigev_signo; 1456 ksi.ksi_code = SI_TIMER; 1457 ksi.ksi_value = pt->pt_ev.sigev_value; 1458 pt->pt_poverruns = pt->pt_overruns; 1459 pt->pt_overruns = 0; 1460 mutex_spin_exit(&timer_lock); 1461 kpsignal(p, &ksi, NULL); 1462 mutex_spin_enter(&timer_lock); 1463 } 1464 mutex_spin_exit(&timer_lock); 1465 mutex_exit(proc_lock); 1466} 1467 1468/* 1469 * Check if the time will wrap if set to ts. 1470 * 1471 * ts - timespec describing the new time 1472 * delta - the delta between the current time and ts 1473 */ 1474bool 1475time_wraps(struct timespec *ts, struct timespec *delta) 1476{ 1477 1478 /* 1479 * Don't allow the time to be set forward so far it 1480 * will wrap and become negative, thus allowing an 1481 * attacker to bypass the next check below. The 1482 * cutoff is 1 year before rollover occurs, so even 1483 * if the attacker uses adjtime(2) to move the time 1484 * past the cutoff, it will take a very long time 1485 * to get to the wrap point. 1486 */ 1487 if ((ts->tv_sec > LLONG_MAX - 365*24*60*60) || 1488 (delta->tv_sec < 0 || delta->tv_nsec < 0)) 1489 return true; 1490 1491 return false; 1492} 1493