1 /* $NetBSD: kern_time.c,v 1.213 2022/03/13 12:21:28 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2000, 2004, 2005, 2007, 2008, 2009, 2020 5 * The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Christopher G. Demetriou, by Andrew Doran, and by Jason R. Thorpe. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1989, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)kern_time.c 8.4 (Berkeley) 5/26/95 62 */ 63 64 #include <sys/cdefs.h> 65 __KERNEL_RCSID(0, "$NetBSD: kern_time.c,v 1.213 2022/03/13 12:21:28 riastradh Exp $"); 66 67 #include <sys/param.h> 68 #include <sys/resourcevar.h> 69 #include <sys/kernel.h> 70 #include <sys/systm.h> 71 #include <sys/proc.h> 72 #include <sys/vnode.h> 73 #include <sys/signalvar.h> 74 #include <sys/syslog.h> 75 #include <sys/timetc.h> 76 #include <sys/timex.h> 77 #include <sys/kauth.h> 78 #include <sys/mount.h> 79 #include <sys/syscallargs.h> 80 #include <sys/cpu.h> 81 82 kmutex_t itimer_mutex __cacheline_aligned; /* XXX static */ 83 static struct itlist itimer_realtime_changed_notify; 84 85 static void ptimer_intr(void *); 86 static void *ptimer_sih __read_mostly; 87 static TAILQ_HEAD(, ptimer) ptimer_queue; 88 89 #define CLOCK_VIRTUAL_P(clockid) \ 90 ((clockid) == CLOCK_VIRTUAL || (clockid) == CLOCK_PROF) 91 92 CTASSERT(ITIMER_REAL == CLOCK_REALTIME); 93 CTASSERT(ITIMER_VIRTUAL == CLOCK_VIRTUAL); 94 CTASSERT(ITIMER_PROF == CLOCK_PROF); 95 CTASSERT(ITIMER_MONOTONIC == CLOCK_MONOTONIC); 96 97 #define DELAYTIMER_MAX 32 98 99 /* 100 * Initialize timekeeping. 101 */ 102 void 103 time_init(void) 104 { 105 106 mutex_init(&itimer_mutex, MUTEX_DEFAULT, IPL_SCHED); 107 LIST_INIT(&itimer_realtime_changed_notify); 108 109 TAILQ_INIT(&ptimer_queue); 110 ptimer_sih = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE, 111 ptimer_intr, NULL); 112 } 113 114 /* 115 * Check if the time will wrap if set to ts. 116 * 117 * ts - timespec describing the new time 118 * delta - the delta between the current time and ts 119 */ 120 bool 121 time_wraps(struct timespec *ts, struct timespec *delta) 122 { 123 124 /* 125 * Don't allow the time to be set forward so far it 126 * will wrap and become negative, thus allowing an 127 * attacker to bypass the next check below. The 128 * cutoff is 1 year before rollover occurs, so even 129 * if the attacker uses adjtime(2) to move the time 130 * past the cutoff, it will take a very long time 131 * to get to the wrap point. 132 */ 133 if ((ts->tv_sec > LLONG_MAX - 365*24*60*60) || 134 (delta->tv_sec < 0 || delta->tv_nsec < 0)) 135 return true; 136 137 return false; 138 } 139 140 /* 141 * itimer_lock: 142 * 143 * Acquire the interval timer data lock. 144 */ 145 void 146 itimer_lock(void) 147 { 148 mutex_spin_enter(&itimer_mutex); 149 } 150 151 /* 152 * itimer_unlock: 153 * 154 * Release the interval timer data lock. 155 */ 156 void 157 itimer_unlock(void) 158 { 159 mutex_spin_exit(&itimer_mutex); 160 } 161 162 /* 163 * itimer_lock_held: 164 * 165 * Check that the interval timer lock is held for diagnostic 166 * assertions. 167 */ 168 inline bool __diagused 169 itimer_lock_held(void) 170 { 171 return mutex_owned(&itimer_mutex); 172 } 173 174 /* 175 * Time of day and interval timer support. 176 * 177 * These routines provide the kernel entry points to get and set 178 * the time-of-day and per-process interval timers. Subroutines 179 * here provide support for adding and subtracting timeval structures 180 * and decrementing interval timers, optionally reloading the interval 181 * timers when they expire. 182 */ 183 184 /* This function is used by clock_settime and settimeofday */ 185 static int 186 settime1(struct proc *p, const struct timespec *ts, bool check_kauth) 187 { 188 struct timespec delta, now; 189 190 /* 191 * The time being set to an unreasonable value will cause 192 * unreasonable system behaviour. 193 */ 194 if (ts->tv_sec < 0 || ts->tv_sec > (1LL << 36)) 195 return (EINVAL); 196 197 nanotime(&now); 198 timespecsub(ts, &now, &delta); 199 200 if (check_kauth && kauth_authorize_system(kauth_cred_get(), 201 KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_SYSTEM, __UNCONST(ts), 202 &delta, KAUTH_ARG(check_kauth ? false : true)) != 0) { 203 return (EPERM); 204 } 205 206 #ifdef notyet 207 if ((delta.tv_sec < 86400) && securelevel > 0) { /* XXX elad - notyet */ 208 return (EPERM); 209 } 210 #endif 211 212 tc_setclock(ts); 213 214 resettodr(); 215 216 /* 217 * Notify pending CLOCK_REALTIME timers about the real time change. 218 * There may be inactive timers on this list, but this happens 219 * comparatively less often than timers firing, and so it's better 220 * to put the extra checks here than to complicate the other code 221 * path. 222 */ 223 struct itimer *it; 224 itimer_lock(); 225 LIST_FOREACH(it, &itimer_realtime_changed_notify, it_rtchgq) { 226 KASSERT(it->it_ops->ito_realtime_changed != NULL); 227 if (timespecisset(&it->it_time.it_value)) { 228 (*it->it_ops->ito_realtime_changed)(it); 229 } 230 } 231 itimer_unlock(); 232 233 return (0); 234 } 235 236 int 237 settime(struct proc *p, struct timespec *ts) 238 { 239 return (settime1(p, ts, true)); 240 } 241 242 /* ARGSUSED */ 243 int 244 sys___clock_gettime50(struct lwp *l, 245 const struct sys___clock_gettime50_args *uap, register_t *retval) 246 { 247 /* { 248 syscallarg(clockid_t) clock_id; 249 syscallarg(struct timespec *) tp; 250 } */ 251 int error; 252 struct timespec ats; 253 254 error = clock_gettime1(SCARG(uap, clock_id), &ats); 255 if (error != 0) 256 return error; 257 258 return copyout(&ats, SCARG(uap, tp), sizeof(ats)); 259 } 260 261 /* ARGSUSED */ 262 int 263 sys___clock_settime50(struct lwp *l, 264 const struct sys___clock_settime50_args *uap, register_t *retval) 265 { 266 /* { 267 syscallarg(clockid_t) clock_id; 268 syscallarg(const struct timespec *) tp; 269 } */ 270 int error; 271 struct timespec ats; 272 273 if ((error = copyin(SCARG(uap, tp), &ats, sizeof(ats))) != 0) 274 return error; 275 276 return clock_settime1(l->l_proc, SCARG(uap, clock_id), &ats, true); 277 } 278 279 280 int 281 clock_settime1(struct proc *p, clockid_t clock_id, const struct timespec *tp, 282 bool check_kauth) 283 { 284 int error; 285 286 if (tp->tv_nsec < 0 || tp->tv_nsec >= 1000000000L) 287 return EINVAL; 288 289 switch (clock_id) { 290 case CLOCK_REALTIME: 291 if ((error = settime1(p, tp, check_kauth)) != 0) 292 return (error); 293 break; 294 case CLOCK_MONOTONIC: 295 return (EINVAL); /* read-only clock */ 296 default: 297 return (EINVAL); 298 } 299 300 return 0; 301 } 302 303 int 304 sys___clock_getres50(struct lwp *l, const struct sys___clock_getres50_args *uap, 305 register_t *retval) 306 { 307 /* { 308 syscallarg(clockid_t) clock_id; 309 syscallarg(struct timespec *) tp; 310 } */ 311 struct timespec ts; 312 int error; 313 314 if ((error = clock_getres1(SCARG(uap, clock_id), &ts)) != 0) 315 return error; 316 317 if (SCARG(uap, tp)) 318 error = copyout(&ts, SCARG(uap, tp), sizeof(ts)); 319 320 return error; 321 } 322 323 int 324 clock_getres1(clockid_t clock_id, struct timespec *ts) 325 { 326 327 switch (clock_id) { 328 case CLOCK_REALTIME: 329 case CLOCK_MONOTONIC: 330 ts->tv_sec = 0; 331 if (tc_getfrequency() > 1000000000) 332 ts->tv_nsec = 1; 333 else 334 ts->tv_nsec = 1000000000 / tc_getfrequency(); 335 break; 336 default: 337 return EINVAL; 338 } 339 340 return 0; 341 } 342 343 /* ARGSUSED */ 344 int 345 sys___nanosleep50(struct lwp *l, const struct sys___nanosleep50_args *uap, 346 register_t *retval) 347 { 348 /* { 349 syscallarg(struct timespec *) rqtp; 350 syscallarg(struct timespec *) rmtp; 351 } */ 352 struct timespec rmt, rqt; 353 int error, error1; 354 355 error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec)); 356 if (error) 357 return (error); 358 359 error = nanosleep1(l, CLOCK_MONOTONIC, 0, &rqt, 360 SCARG(uap, rmtp) ? &rmt : NULL); 361 if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR)) 362 return error; 363 364 error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt)); 365 return error1 ? error1 : error; 366 } 367 368 /* ARGSUSED */ 369 int 370 sys_clock_nanosleep(struct lwp *l, const struct sys_clock_nanosleep_args *uap, 371 register_t *retval) 372 { 373 /* { 374 syscallarg(clockid_t) clock_id; 375 syscallarg(int) flags; 376 syscallarg(struct timespec *) rqtp; 377 syscallarg(struct timespec *) rmtp; 378 } */ 379 struct timespec rmt, rqt; 380 int error, error1; 381 382 error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec)); 383 if (error) 384 goto out; 385 386 error = nanosleep1(l, SCARG(uap, clock_id), SCARG(uap, flags), &rqt, 387 SCARG(uap, rmtp) ? &rmt : NULL); 388 if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR)) 389 goto out; 390 391 if ((SCARG(uap, flags) & TIMER_ABSTIME) == 0 && 392 (error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt))) != 0) 393 error = error1; 394 out: 395 *retval = error; 396 return 0; 397 } 398 399 int 400 nanosleep1(struct lwp *l, clockid_t clock_id, int flags, struct timespec *rqt, 401 struct timespec *rmt) 402 { 403 struct timespec rmtstart; 404 int error, timo; 405 406 if ((error = ts2timo(clock_id, flags, rqt, &timo, &rmtstart)) != 0) { 407 if (error == ETIMEDOUT) { 408 error = 0; 409 if (rmt != NULL) 410 rmt->tv_sec = rmt->tv_nsec = 0; 411 } 412 return error; 413 } 414 415 /* 416 * Avoid inadvertently sleeping forever 417 */ 418 if (timo == 0) 419 timo = 1; 420 again: 421 error = kpause("nanoslp", true, timo, NULL); 422 if (error == EWOULDBLOCK) 423 error = 0; 424 if (rmt != NULL || error == 0) { 425 struct timespec rmtend; 426 struct timespec t0; 427 struct timespec *t; 428 int err; 429 430 err = clock_gettime1(clock_id, &rmtend); 431 if (err != 0) 432 return err; 433 434 t = (rmt != NULL) ? rmt : &t0; 435 if (flags & TIMER_ABSTIME) { 436 timespecsub(rqt, &rmtend, t); 437 } else { 438 if (timespeccmp(&rmtend, &rmtstart, <)) 439 timespecclear(t); /* clock wound back */ 440 else 441 timespecsub(&rmtend, &rmtstart, t); 442 if (timespeccmp(rqt, t, <)) 443 timespecclear(t); 444 else 445 timespecsub(rqt, t, t); 446 } 447 if (t->tv_sec < 0) 448 timespecclear(t); 449 if (error == 0) { 450 timo = tstohz(t); 451 if (timo > 0) 452 goto again; 453 } 454 } 455 456 if (error == ERESTART) 457 error = EINTR; 458 459 return error; 460 } 461 462 int 463 sys_clock_getcpuclockid2(struct lwp *l, 464 const struct sys_clock_getcpuclockid2_args *uap, 465 register_t *retval) 466 { 467 /* { 468 syscallarg(idtype_t idtype; 469 syscallarg(id_t id); 470 syscallarg(clockid_t *)clock_id; 471 } */ 472 pid_t pid; 473 lwpid_t lid; 474 clockid_t clock_id; 475 id_t id = SCARG(uap, id); 476 477 switch (SCARG(uap, idtype)) { 478 case P_PID: 479 pid = id == 0 ? l->l_proc->p_pid : id; 480 clock_id = CLOCK_PROCESS_CPUTIME_ID | pid; 481 break; 482 case P_LWPID: 483 lid = id == 0 ? l->l_lid : id; 484 clock_id = CLOCK_THREAD_CPUTIME_ID | lid; 485 break; 486 default: 487 return EINVAL; 488 } 489 return copyout(&clock_id, SCARG(uap, clock_id), sizeof(clock_id)); 490 } 491 492 /* ARGSUSED */ 493 int 494 sys___gettimeofday50(struct lwp *l, const struct sys___gettimeofday50_args *uap, 495 register_t *retval) 496 { 497 /* { 498 syscallarg(struct timeval *) tp; 499 syscallarg(void *) tzp; really "struct timezone *"; 500 } */ 501 struct timeval atv; 502 int error = 0; 503 struct timezone tzfake; 504 505 if (SCARG(uap, tp)) { 506 memset(&atv, 0, sizeof(atv)); 507 microtime(&atv); 508 error = copyout(&atv, SCARG(uap, tp), sizeof(atv)); 509 if (error) 510 return (error); 511 } 512 if (SCARG(uap, tzp)) { 513 /* 514 * NetBSD has no kernel notion of time zone, so we just 515 * fake up a timezone struct and return it if demanded. 516 */ 517 tzfake.tz_minuteswest = 0; 518 tzfake.tz_dsttime = 0; 519 error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake)); 520 } 521 return (error); 522 } 523 524 /* ARGSUSED */ 525 int 526 sys___settimeofday50(struct lwp *l, const struct sys___settimeofday50_args *uap, 527 register_t *retval) 528 { 529 /* { 530 syscallarg(const struct timeval *) tv; 531 syscallarg(const void *) tzp; really "const struct timezone *"; 532 } */ 533 534 return settimeofday1(SCARG(uap, tv), true, SCARG(uap, tzp), l, true); 535 } 536 537 int 538 settimeofday1(const struct timeval *utv, bool userspace, 539 const void *utzp, struct lwp *l, bool check_kauth) 540 { 541 struct timeval atv; 542 struct timespec ts; 543 int error; 544 545 /* Verify all parameters before changing time. */ 546 547 /* 548 * NetBSD has no kernel notion of time zone, and only an 549 * obsolete program would try to set it, so we log a warning. 550 */ 551 if (utzp) 552 log(LOG_WARNING, "pid %d attempted to set the " 553 "(obsolete) kernel time zone\n", l->l_proc->p_pid); 554 555 if (utv == NULL) 556 return 0; 557 558 if (userspace) { 559 if ((error = copyin(utv, &atv, sizeof(atv))) != 0) 560 return error; 561 utv = &atv; 562 } 563 564 if (utv->tv_usec < 0 || utv->tv_usec >= 1000000) 565 return EINVAL; 566 567 TIMEVAL_TO_TIMESPEC(utv, &ts); 568 return settime1(l->l_proc, &ts, check_kauth); 569 } 570 571 int time_adjusted; /* set if an adjustment is made */ 572 573 /* ARGSUSED */ 574 int 575 sys___adjtime50(struct lwp *l, const struct sys___adjtime50_args *uap, 576 register_t *retval) 577 { 578 /* { 579 syscallarg(const struct timeval *) delta; 580 syscallarg(struct timeval *) olddelta; 581 } */ 582 int error; 583 struct timeval atv, oldatv; 584 585 if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_TIME, 586 KAUTH_REQ_SYSTEM_TIME_ADJTIME, NULL, NULL, NULL)) != 0) 587 return error; 588 589 if (SCARG(uap, delta)) { 590 error = copyin(SCARG(uap, delta), &atv, 591 sizeof(*SCARG(uap, delta))); 592 if (error) 593 return (error); 594 } 595 adjtime1(SCARG(uap, delta) ? &atv : NULL, 596 SCARG(uap, olddelta) ? &oldatv : NULL, l->l_proc); 597 if (SCARG(uap, olddelta)) 598 error = copyout(&oldatv, SCARG(uap, olddelta), 599 sizeof(*SCARG(uap, olddelta))); 600 return error; 601 } 602 603 void 604 adjtime1(const struct timeval *delta, struct timeval *olddelta, struct proc *p) 605 { 606 extern int64_t time_adjtime; /* in kern_ntptime.c */ 607 608 if (olddelta) { 609 memset(olddelta, 0, sizeof(*olddelta)); 610 mutex_spin_enter(&timecounter_lock); 611 olddelta->tv_sec = time_adjtime / 1000000; 612 olddelta->tv_usec = time_adjtime % 1000000; 613 if (olddelta->tv_usec < 0) { 614 olddelta->tv_usec += 1000000; 615 olddelta->tv_sec--; 616 } 617 mutex_spin_exit(&timecounter_lock); 618 } 619 620 if (delta) { 621 mutex_spin_enter(&timecounter_lock); 622 /* 623 * XXX This should maybe just report failure to 624 * userland for nonsense deltas. 625 */ 626 if (delta->tv_sec > INT64_MAX/1000000 - 1) { 627 time_adjtime = INT64_MAX; 628 } else { 629 time_adjtime = MAX(0, delta->tv_sec) * 1000000 630 + MAX(0, MIN(999999, delta->tv_usec)); 631 } 632 633 if (time_adjtime) { 634 /* We need to save the system time during shutdown */ 635 time_adjusted |= 1; 636 } 637 mutex_spin_exit(&timecounter_lock); 638 } 639 } 640 641 /* 642 * Interval timer support. 643 * 644 * The itimer_*() routines provide generic support for interval timers, 645 * both real (CLOCK_REALTIME, CLOCK_MONOTIME), and virtual (CLOCK_VIRTUAL, 646 * CLOCK_PROF). 647 * 648 * Real timers keep their deadline as an absolute time, and are fired 649 * by a callout. Virtual timers are kept as a linked-list of deltas, 650 * and are processed by hardclock(). 651 * 652 * Because the real time timer callout may be delayed in real time due 653 * to interrupt processing on the system, it is possible for the real 654 * time timeout routine (itimer_callout()) run past after its deadline. 655 * It does not suffice, therefore, to reload the real timer .it_value 656 * from the timer's .it_interval. Rather, we compute the next deadline 657 * in absolute time based on the current time and the .it_interval value, 658 * and report any overruns. 659 * 660 * Note that while the virtual timers are supported in a generic fashion 661 * here, they only (currently) make sense as per-process timers, and thus 662 * only really work for that case. 663 */ 664 665 /* 666 * itimer_init: 667 * 668 * Initialize the common data for an interval timer. 669 */ 670 void 671 itimer_init(struct itimer * const it, const struct itimer_ops * const ops, 672 clockid_t const id, struct itlist * const itl) 673 { 674 675 KASSERT(itimer_lock_held()); 676 KASSERT(ops != NULL); 677 678 timespecclear(&it->it_time.it_value); 679 it->it_ops = ops; 680 it->it_clockid = id; 681 it->it_overruns = 0; 682 it->it_dying = false; 683 if (!CLOCK_VIRTUAL_P(id)) { 684 KASSERT(itl == NULL); 685 callout_init(&it->it_ch, CALLOUT_MPSAFE); 686 if (id == CLOCK_REALTIME && ops->ito_realtime_changed != NULL) { 687 LIST_INSERT_HEAD(&itimer_realtime_changed_notify, 688 it, it_rtchgq); 689 } 690 } else { 691 KASSERT(itl != NULL); 692 it->it_vlist = itl; 693 it->it_active = false; 694 } 695 } 696 697 /* 698 * itimer_poison: 699 * 700 * Poison an interval timer, preventing it from being scheduled 701 * or processed, in preparation for freeing the timer. 702 */ 703 void 704 itimer_poison(struct itimer * const it) 705 { 706 707 KASSERT(itimer_lock_held()); 708 709 it->it_dying = true; 710 711 /* 712 * For non-virtual timers, stop the callout, or wait for it to 713 * run if it has already fired. It cannot restart again after 714 * this point: the callout won't restart itself when dying, no 715 * other users holding the lock can restart it, and any other 716 * users waiting for callout_halt concurrently (itimer_settime) 717 * will restart from the top. 718 */ 719 if (!CLOCK_VIRTUAL_P(it->it_clockid)) { 720 callout_halt(&it->it_ch, &itimer_mutex); 721 if (it->it_clockid == CLOCK_REALTIME && 722 it->it_ops->ito_realtime_changed != NULL) { 723 LIST_REMOVE(it, it_rtchgq); 724 } 725 } 726 } 727 728 /* 729 * itimer_fini: 730 * 731 * Release resources used by an interval timer. 732 * 733 * N.B. itimer_lock must be held on entry, and is released on exit. 734 */ 735 void 736 itimer_fini(struct itimer * const it) 737 { 738 739 KASSERT(itimer_lock_held()); 740 741 /* All done with the global state. */ 742 itimer_unlock(); 743 744 /* Destroy the callout, if needed. */ 745 if (!CLOCK_VIRTUAL_P(it->it_clockid)) 746 callout_destroy(&it->it_ch); 747 } 748 749 /* 750 * itimer_decr: 751 * 752 * Decrement an interval timer by a specified number of nanoseconds, 753 * which must be less than a second, i.e. < 1000000000. If the timer 754 * expires, then reload it. In this case, carry over (nsec - old value) 755 * to reduce the value reloaded into the timer so that the timer does 756 * not drift. This routine assumes that it is called in a context where 757 * the timers on which it is operating cannot change in value. 758 * 759 * Returns true if the timer has expired. 760 */ 761 static bool 762 itimer_decr(struct itimer *it, int nsec) 763 { 764 struct itimerspec *itp; 765 int error __diagused; 766 767 KASSERT(itimer_lock_held()); 768 KASSERT(CLOCK_VIRTUAL_P(it->it_clockid)); 769 770 itp = &it->it_time; 771 if (itp->it_value.tv_nsec < nsec) { 772 if (itp->it_value.tv_sec == 0) { 773 /* expired, and already in next interval */ 774 nsec -= itp->it_value.tv_nsec; 775 goto expire; 776 } 777 itp->it_value.tv_nsec += 1000000000; 778 itp->it_value.tv_sec--; 779 } 780 itp->it_value.tv_nsec -= nsec; 781 nsec = 0; 782 if (timespecisset(&itp->it_value)) 783 return false; 784 /* expired, exactly at end of interval */ 785 expire: 786 if (timespecisset(&itp->it_interval)) { 787 itp->it_value = itp->it_interval; 788 itp->it_value.tv_nsec -= nsec; 789 if (itp->it_value.tv_nsec < 0) { 790 itp->it_value.tv_nsec += 1000000000; 791 itp->it_value.tv_sec--; 792 } 793 error = itimer_settime(it); 794 KASSERT(error == 0); /* virtual, never fails */ 795 } else 796 itp->it_value.tv_nsec = 0; /* sec is already 0 */ 797 return true; 798 } 799 800 static void itimer_callout(void *); 801 802 /* 803 * itimer_arm_real: 804 * 805 * Arm a non-virtual timer. 806 */ 807 static void 808 itimer_arm_real(struct itimer * const it) 809 { 810 /* 811 * Don't need to check tshzto() return value, here. 812 * callout_reset() does it for us. 813 */ 814 callout_reset(&it->it_ch, 815 (it->it_clockid == CLOCK_MONOTONIC 816 ? tshztoup(&it->it_time.it_value) 817 : tshzto(&it->it_time.it_value)), 818 itimer_callout, it); 819 } 820 821 /* 822 * itimer_callout: 823 * 824 * Callout to expire a non-virtual timer. Queue it up for processing, 825 * and then reload, if it is configured to do so. 826 * 827 * N.B. A delay in processing this callout causes multiple 828 * SIGALRM calls to be compressed into one. 829 */ 830 static void 831 itimer_callout(void *arg) 832 { 833 uint64_t last_val, next_val, interval, now_ns; 834 struct timespec now, next; 835 struct itimer * const it = arg; 836 int backwards; 837 838 itimer_lock(); 839 (*it->it_ops->ito_fire)(it); 840 841 if (!timespecisset(&it->it_time.it_interval)) { 842 timespecclear(&it->it_time.it_value); 843 itimer_unlock(); 844 return; 845 } 846 847 if (it->it_clockid == CLOCK_MONOTONIC) { 848 getnanouptime(&now); 849 } else { 850 getnanotime(&now); 851 } 852 backwards = (timespeccmp(&it->it_time.it_value, &now, >)); 853 timespecadd(&it->it_time.it_value, &it->it_time.it_interval, &next); 854 /* Handle the easy case of non-overflown timers first. */ 855 if (!backwards && timespeccmp(&next, &now, >)) { 856 it->it_time.it_value = next; 857 } else { 858 now_ns = timespec2ns(&now); 859 last_val = timespec2ns(&it->it_time.it_value); 860 interval = timespec2ns(&it->it_time.it_interval); 861 862 next_val = now_ns + 863 (now_ns - last_val + interval - 1) % interval; 864 865 if (backwards) 866 next_val += interval; 867 else 868 it->it_overruns += (now_ns - last_val) / interval; 869 870 it->it_time.it_value.tv_sec = next_val / 1000000000; 871 it->it_time.it_value.tv_nsec = next_val % 1000000000; 872 } 873 874 /* 875 * Reset the callout, if it's not going away. 876 */ 877 if (!it->it_dying) 878 itimer_arm_real(it); 879 itimer_unlock(); 880 } 881 882 /* 883 * itimer_settime: 884 * 885 * Set up the given interval timer. The value in it->it_time.it_value 886 * is taken to be an absolute time for CLOCK_REALTIME/CLOCK_MONOTONIC 887 * timers and a relative time for CLOCK_VIRTUAL/CLOCK_PROF timers. 888 * 889 * If the callout had already fired but not yet run, fails with 890 * ERESTART -- caller must restart from the top to look up a timer. 891 */ 892 int 893 itimer_settime(struct itimer *it) 894 { 895 struct itimer *itn, *pitn; 896 struct itlist *itl; 897 898 KASSERT(itimer_lock_held()); 899 900 if (!CLOCK_VIRTUAL_P(it->it_clockid)) { 901 /* 902 * Try to stop the callout. However, if it had already 903 * fired, we have to drop the lock to wait for it, so 904 * the world may have changed and pt may not be there 905 * any more. In that case, tell the caller to start 906 * over from the top. 907 */ 908 if (callout_halt(&it->it_ch, &itimer_mutex)) 909 return ERESTART; 910 911 /* Now we can touch it and start it up again. */ 912 if (timespecisset(&it->it_time.it_value)) 913 itimer_arm_real(it); 914 } else { 915 if (it->it_active) { 916 itn = LIST_NEXT(it, it_list); 917 LIST_REMOVE(it, it_list); 918 for ( ; itn; itn = LIST_NEXT(itn, it_list)) 919 timespecadd(&it->it_time.it_value, 920 &itn->it_time.it_value, 921 &itn->it_time.it_value); 922 } 923 if (timespecisset(&it->it_time.it_value)) { 924 itl = it->it_vlist; 925 for (itn = LIST_FIRST(itl), pitn = NULL; 926 itn && timespeccmp(&it->it_time.it_value, 927 &itn->it_time.it_value, >); 928 pitn = itn, itn = LIST_NEXT(itn, it_list)) 929 timespecsub(&it->it_time.it_value, 930 &itn->it_time.it_value, 931 &it->it_time.it_value); 932 933 if (pitn) 934 LIST_INSERT_AFTER(pitn, it, it_list); 935 else 936 LIST_INSERT_HEAD(itl, it, it_list); 937 938 for ( ; itn ; itn = LIST_NEXT(itn, it_list)) 939 timespecsub(&itn->it_time.it_value, 940 &it->it_time.it_value, 941 &itn->it_time.it_value); 942 943 it->it_active = true; 944 } else { 945 it->it_active = false; 946 } 947 } 948 949 /* Success! */ 950 return 0; 951 } 952 953 /* 954 * itimer_gettime: 955 * 956 * Return the remaining time of an interval timer. 957 */ 958 void 959 itimer_gettime(const struct itimer *it, struct itimerspec *aits) 960 { 961 struct timespec now; 962 struct itimer *itn; 963 964 KASSERT(itimer_lock_held()); 965 966 *aits = it->it_time; 967 if (!CLOCK_VIRTUAL_P(it->it_clockid)) { 968 /* 969 * Convert from absolute to relative time in .it_value 970 * part of real time timer. If time for real time 971 * timer has passed return 0, else return difference 972 * between current time and time for the timer to go 973 * off. 974 */ 975 if (timespecisset(&aits->it_value)) { 976 if (it->it_clockid == CLOCK_REALTIME) { 977 getnanotime(&now); 978 } else { /* CLOCK_MONOTONIC */ 979 getnanouptime(&now); 980 } 981 if (timespeccmp(&aits->it_value, &now, <)) 982 timespecclear(&aits->it_value); 983 else 984 timespecsub(&aits->it_value, &now, 985 &aits->it_value); 986 } 987 } else if (it->it_active) { 988 for (itn = LIST_FIRST(it->it_vlist); itn && itn != it; 989 itn = LIST_NEXT(itn, it_list)) 990 timespecadd(&aits->it_value, 991 &itn->it_time.it_value, &aits->it_value); 992 KASSERT(itn != NULL); /* it should be findable on the list */ 993 } else 994 timespecclear(&aits->it_value); 995 } 996 997 /* 998 * Per-process timer support. 999 * 1000 * Both the BSD getitimer() family and the POSIX timer_*() family of 1001 * routines are supported. 1002 * 1003 * All timers are kept in an array pointed to by p_timers, which is 1004 * allocated on demand - many processes don't use timers at all. The 1005 * first four elements in this array are reserved for the BSD timers: 1006 * element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, element 1007 * 2 is ITIMER_PROF, and element 3 is ITIMER_MONOTONIC. The rest may be 1008 * allocated by the timer_create() syscall. 1009 * 1010 * These timers are a "sub-class" of interval timer. 1011 */ 1012 1013 /* 1014 * ptimer_free: 1015 * 1016 * Free the per-process timer at the specified index. 1017 */ 1018 static void 1019 ptimer_free(struct ptimers *pts, int index) 1020 { 1021 struct itimer *it; 1022 struct ptimer *pt; 1023 1024 KASSERT(itimer_lock_held()); 1025 1026 it = pts->pts_timers[index]; 1027 pt = container_of(it, struct ptimer, pt_itimer); 1028 pts->pts_timers[index] = NULL; 1029 itimer_poison(it); 1030 1031 /* 1032 * Remove it from the queue to be signalled. Must be done 1033 * after itimer is poisoned, because we may have had to wait 1034 * for the callout to complete. 1035 */ 1036 if (pt->pt_queued) { 1037 TAILQ_REMOVE(&ptimer_queue, pt, pt_chain); 1038 pt->pt_queued = false; 1039 } 1040 1041 itimer_fini(it); /* releases itimer_lock */ 1042 kmem_free(pt, sizeof(*pt)); 1043 } 1044 1045 /* 1046 * ptimers_alloc: 1047 * 1048 * Allocate a ptimers for the specified process. 1049 */ 1050 static struct ptimers * 1051 ptimers_alloc(struct proc *p) 1052 { 1053 struct ptimers *pts; 1054 int i; 1055 1056 pts = kmem_alloc(sizeof(*pts), KM_SLEEP); 1057 LIST_INIT(&pts->pts_virtual); 1058 LIST_INIT(&pts->pts_prof); 1059 for (i = 0; i < TIMER_MAX; i++) 1060 pts->pts_timers[i] = NULL; 1061 itimer_lock(); 1062 if (p->p_timers == NULL) { 1063 p->p_timers = pts; 1064 itimer_unlock(); 1065 return pts; 1066 } 1067 itimer_unlock(); 1068 kmem_free(pts, sizeof(*pts)); 1069 return p->p_timers; 1070 } 1071 1072 /* 1073 * ptimers_free: 1074 * 1075 * Clean up the per-process timers. If "which" is set to TIMERS_ALL, 1076 * then clean up all timers and free all the data structures. If 1077 * "which" is set to TIMERS_POSIX, only clean up the timers allocated 1078 * by timer_create(), not the BSD setitimer() timers, and only free the 1079 * structure if none of those remain. 1080 * 1081 * This function is exported because it is needed in the exec and 1082 * exit code paths. 1083 */ 1084 void 1085 ptimers_free(struct proc *p, int which) 1086 { 1087 struct ptimers *pts; 1088 struct itimer *itn; 1089 struct timespec ts; 1090 int i; 1091 1092 if (p->p_timers == NULL) 1093 return; 1094 1095 pts = p->p_timers; 1096 itimer_lock(); 1097 if (which == TIMERS_ALL) { 1098 p->p_timers = NULL; 1099 i = 0; 1100 } else { 1101 timespecclear(&ts); 1102 for (itn = LIST_FIRST(&pts->pts_virtual); 1103 itn && itn != pts->pts_timers[ITIMER_VIRTUAL]; 1104 itn = LIST_NEXT(itn, it_list)) { 1105 KASSERT(itn->it_clockid == CLOCK_VIRTUAL); 1106 timespecadd(&ts, &itn->it_time.it_value, &ts); 1107 } 1108 LIST_FIRST(&pts->pts_virtual) = NULL; 1109 if (itn) { 1110 KASSERT(itn->it_clockid == CLOCK_VIRTUAL); 1111 timespecadd(&ts, &itn->it_time.it_value, 1112 &itn->it_time.it_value); 1113 LIST_INSERT_HEAD(&pts->pts_virtual, itn, it_list); 1114 } 1115 timespecclear(&ts); 1116 for (itn = LIST_FIRST(&pts->pts_prof); 1117 itn && itn != pts->pts_timers[ITIMER_PROF]; 1118 itn = LIST_NEXT(itn, it_list)) { 1119 KASSERT(itn->it_clockid == CLOCK_PROF); 1120 timespecadd(&ts, &itn->it_time.it_value, &ts); 1121 } 1122 LIST_FIRST(&pts->pts_prof) = NULL; 1123 if (itn) { 1124 KASSERT(itn->it_clockid == CLOCK_PROF); 1125 timespecadd(&ts, &itn->it_time.it_value, 1126 &itn->it_time.it_value); 1127 LIST_INSERT_HEAD(&pts->pts_prof, itn, it_list); 1128 } 1129 i = TIMER_MIN; 1130 } 1131 for ( ; i < TIMER_MAX; i++) { 1132 if (pts->pts_timers[i] != NULL) { 1133 /* Free the timer and release the lock. */ 1134 ptimer_free(pts, i); 1135 /* Reacquire the lock for the next one. */ 1136 itimer_lock(); 1137 } 1138 } 1139 if (pts->pts_timers[0] == NULL && pts->pts_timers[1] == NULL && 1140 pts->pts_timers[2] == NULL && pts->pts_timers[3] == NULL) { 1141 p->p_timers = NULL; 1142 itimer_unlock(); 1143 kmem_free(pts, sizeof(*pts)); 1144 } else 1145 itimer_unlock(); 1146 } 1147 1148 /* 1149 * ptimer_fire: 1150 * 1151 * Fire a per-process timer. 1152 */ 1153 static void 1154 ptimer_fire(struct itimer *it) 1155 { 1156 struct ptimer *pt = container_of(it, struct ptimer, pt_itimer); 1157 1158 KASSERT(itimer_lock_held()); 1159 1160 /* 1161 * XXX Can overrun, but we don't do signal queueing yet, anyway. 1162 * XXX Relying on the clock interrupt is stupid. 1163 */ 1164 if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL) { 1165 return; 1166 } 1167 1168 if (!pt->pt_queued) { 1169 TAILQ_INSERT_TAIL(&ptimer_queue, pt, pt_chain); 1170 pt->pt_queued = true; 1171 softint_schedule(ptimer_sih); 1172 } 1173 } 1174 1175 /* 1176 * Operations vector for per-process timers (BSD and POSIX). 1177 */ 1178 static const struct itimer_ops ptimer_itimer_ops = { 1179 .ito_fire = ptimer_fire, 1180 }; 1181 1182 /* 1183 * sys_timer_create: 1184 * 1185 * System call to create a POSIX timer. 1186 */ 1187 int 1188 sys_timer_create(struct lwp *l, const struct sys_timer_create_args *uap, 1189 register_t *retval) 1190 { 1191 /* { 1192 syscallarg(clockid_t) clock_id; 1193 syscallarg(struct sigevent *) evp; 1194 syscallarg(timer_t *) timerid; 1195 } */ 1196 1197 return timer_create1(SCARG(uap, timerid), SCARG(uap, clock_id), 1198 SCARG(uap, evp), copyin, l); 1199 } 1200 1201 int 1202 timer_create1(timer_t *tid, clockid_t id, struct sigevent *evp, 1203 copyin_t fetch_event, struct lwp *l) 1204 { 1205 int error; 1206 timer_t timerid; 1207 struct itlist *itl; 1208 struct ptimers *pts; 1209 struct ptimer *pt; 1210 struct proc *p; 1211 1212 p = l->l_proc; 1213 1214 if ((u_int)id > CLOCK_MONOTONIC) 1215 return (EINVAL); 1216 1217 if ((pts = p->p_timers) == NULL) 1218 pts = ptimers_alloc(p); 1219 1220 pt = kmem_zalloc(sizeof(*pt), KM_SLEEP); 1221 if (evp != NULL) { 1222 if (((error = 1223 (*fetch_event)(evp, &pt->pt_ev, sizeof(pt->pt_ev))) != 0) || 1224 ((pt->pt_ev.sigev_notify < SIGEV_NONE) || 1225 (pt->pt_ev.sigev_notify > SIGEV_SA)) || 1226 (pt->pt_ev.sigev_notify == SIGEV_SIGNAL && 1227 (pt->pt_ev.sigev_signo <= 0 || 1228 pt->pt_ev.sigev_signo >= NSIG))) { 1229 kmem_free(pt, sizeof(*pt)); 1230 return (error ? error : EINVAL); 1231 } 1232 } 1233 1234 /* Find a free timer slot, skipping those reserved for setitimer(). */ 1235 itimer_lock(); 1236 for (timerid = TIMER_MIN; timerid < TIMER_MAX; timerid++) 1237 if (pts->pts_timers[timerid] == NULL) 1238 break; 1239 if (timerid == TIMER_MAX) { 1240 itimer_unlock(); 1241 kmem_free(pt, sizeof(*pt)); 1242 return EAGAIN; 1243 } 1244 if (evp == NULL) { 1245 pt->pt_ev.sigev_notify = SIGEV_SIGNAL; 1246 switch (id) { 1247 case CLOCK_REALTIME: 1248 case CLOCK_MONOTONIC: 1249 pt->pt_ev.sigev_signo = SIGALRM; 1250 break; 1251 case CLOCK_VIRTUAL: 1252 pt->pt_ev.sigev_signo = SIGVTALRM; 1253 break; 1254 case CLOCK_PROF: 1255 pt->pt_ev.sigev_signo = SIGPROF; 1256 break; 1257 } 1258 pt->pt_ev.sigev_value.sival_int = timerid; 1259 } 1260 1261 switch (id) { 1262 case CLOCK_VIRTUAL: 1263 itl = &pts->pts_virtual; 1264 break; 1265 case CLOCK_PROF: 1266 itl = &pts->pts_prof; 1267 break; 1268 default: 1269 itl = NULL; 1270 } 1271 1272 itimer_init(&pt->pt_itimer, &ptimer_itimer_ops, id, itl); 1273 pt->pt_proc = p; 1274 pt->pt_poverruns = 0; 1275 pt->pt_entry = timerid; 1276 pt->pt_queued = false; 1277 1278 pts->pts_timers[timerid] = &pt->pt_itimer; 1279 itimer_unlock(); 1280 1281 return copyout(&timerid, tid, sizeof(timerid)); 1282 } 1283 1284 /* 1285 * sys_timer_delete: 1286 * 1287 * System call to delete a POSIX timer. 1288 */ 1289 int 1290 sys_timer_delete(struct lwp *l, const struct sys_timer_delete_args *uap, 1291 register_t *retval) 1292 { 1293 /* { 1294 syscallarg(timer_t) timerid; 1295 } */ 1296 struct proc *p = l->l_proc; 1297 timer_t timerid; 1298 struct ptimers *pts; 1299 struct itimer *it, *itn; 1300 1301 timerid = SCARG(uap, timerid); 1302 pts = p->p_timers; 1303 1304 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 1305 return (EINVAL); 1306 1307 itimer_lock(); 1308 if ((it = pts->pts_timers[timerid]) == NULL) { 1309 itimer_unlock(); 1310 return (EINVAL); 1311 } 1312 1313 if (CLOCK_VIRTUAL_P(it->it_clockid)) { 1314 if (it->it_active) { 1315 itn = LIST_NEXT(it, it_list); 1316 LIST_REMOVE(it, it_list); 1317 for ( ; itn; itn = LIST_NEXT(itn, it_list)) 1318 timespecadd(&it->it_time.it_value, 1319 &itn->it_time.it_value, 1320 &itn->it_time.it_value); 1321 it->it_active = false; 1322 } 1323 } 1324 1325 /* Free the timer and release the lock. */ 1326 ptimer_free(pts, timerid); 1327 1328 return (0); 1329 } 1330 1331 /* 1332 * sys___timer_settime50: 1333 * 1334 * System call to set/arm a POSIX timer. 1335 */ 1336 int 1337 sys___timer_settime50(struct lwp *l, 1338 const struct sys___timer_settime50_args *uap, 1339 register_t *retval) 1340 { 1341 /* { 1342 syscallarg(timer_t) timerid; 1343 syscallarg(int) flags; 1344 syscallarg(const struct itimerspec *) value; 1345 syscallarg(struct itimerspec *) ovalue; 1346 } */ 1347 int error; 1348 struct itimerspec value, ovalue, *ovp = NULL; 1349 1350 if ((error = copyin(SCARG(uap, value), &value, 1351 sizeof(struct itimerspec))) != 0) 1352 return (error); 1353 1354 if (SCARG(uap, ovalue)) 1355 ovp = &ovalue; 1356 1357 if ((error = dotimer_settime(SCARG(uap, timerid), &value, ovp, 1358 SCARG(uap, flags), l->l_proc)) != 0) 1359 return error; 1360 1361 if (ovp) 1362 return copyout(&ovalue, SCARG(uap, ovalue), 1363 sizeof(struct itimerspec)); 1364 return 0; 1365 } 1366 1367 int 1368 dotimer_settime(int timerid, struct itimerspec *value, 1369 struct itimerspec *ovalue, int flags, struct proc *p) 1370 { 1371 struct timespec now; 1372 struct itimerspec val, oval; 1373 struct ptimers *pts; 1374 struct itimer *it; 1375 int error; 1376 1377 pts = p->p_timers; 1378 1379 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 1380 return EINVAL; 1381 val = *value; 1382 if ((error = itimespecfix(&val.it_value)) != 0 || 1383 (error = itimespecfix(&val.it_interval)) != 0) 1384 return error; 1385 1386 itimer_lock(); 1387 restart: 1388 if ((it = pts->pts_timers[timerid]) == NULL) { 1389 itimer_unlock(); 1390 return EINVAL; 1391 } 1392 1393 oval = it->it_time; 1394 it->it_time = val; 1395 1396 /* 1397 * If we've been passed a relative time for a realtime timer, 1398 * convert it to absolute; if an absolute time for a virtual 1399 * timer, convert it to relative and make sure we don't set it 1400 * to zero, which would cancel the timer, or let it go 1401 * negative, which would confuse the comparison tests. 1402 */ 1403 if (timespecisset(&it->it_time.it_value)) { 1404 if (!CLOCK_VIRTUAL_P(it->it_clockid)) { 1405 if ((flags & TIMER_ABSTIME) == 0) { 1406 if (it->it_clockid == CLOCK_REALTIME) { 1407 getnanotime(&now); 1408 } else { /* CLOCK_MONOTONIC */ 1409 getnanouptime(&now); 1410 } 1411 timespecadd(&it->it_time.it_value, &now, 1412 &it->it_time.it_value); 1413 } 1414 } else { 1415 if ((flags & TIMER_ABSTIME) != 0) { 1416 getnanotime(&now); 1417 timespecsub(&it->it_time.it_value, &now, 1418 &it->it_time.it_value); 1419 if (!timespecisset(&it->it_time.it_value) || 1420 it->it_time.it_value.tv_sec < 0) { 1421 it->it_time.it_value.tv_sec = 0; 1422 it->it_time.it_value.tv_nsec = 1; 1423 } 1424 } 1425 } 1426 } 1427 1428 error = itimer_settime(it); 1429 if (error == ERESTART) { 1430 KASSERT(!CLOCK_VIRTUAL_P(it->it_clockid)); 1431 goto restart; 1432 } 1433 KASSERT(error == 0); 1434 itimer_unlock(); 1435 1436 if (ovalue) 1437 *ovalue = oval; 1438 1439 return (0); 1440 } 1441 1442 /* 1443 * sys___timer_gettime50: 1444 * 1445 * System call to return the time remaining until a POSIX timer fires. 1446 */ 1447 int 1448 sys___timer_gettime50(struct lwp *l, 1449 const struct sys___timer_gettime50_args *uap, register_t *retval) 1450 { 1451 /* { 1452 syscallarg(timer_t) timerid; 1453 syscallarg(struct itimerspec *) value; 1454 } */ 1455 struct itimerspec its; 1456 int error; 1457 1458 if ((error = dotimer_gettime(SCARG(uap, timerid), l->l_proc, 1459 &its)) != 0) 1460 return error; 1461 1462 return copyout(&its, SCARG(uap, value), sizeof(its)); 1463 } 1464 1465 int 1466 dotimer_gettime(int timerid, struct proc *p, struct itimerspec *its) 1467 { 1468 struct itimer *it; 1469 struct ptimers *pts; 1470 1471 pts = p->p_timers; 1472 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 1473 return (EINVAL); 1474 itimer_lock(); 1475 if ((it = pts->pts_timers[timerid]) == NULL) { 1476 itimer_unlock(); 1477 return (EINVAL); 1478 } 1479 itimer_gettime(it, its); 1480 itimer_unlock(); 1481 1482 return 0; 1483 } 1484 1485 /* 1486 * sys_timer_getoverrun: 1487 * 1488 * System call to return the number of times a POSIX timer has 1489 * expired while a notification was already pending. The counter 1490 * is reset when a timer expires and a notification can be posted. 1491 */ 1492 int 1493 sys_timer_getoverrun(struct lwp *l, const struct sys_timer_getoverrun_args *uap, 1494 register_t *retval) 1495 { 1496 /* { 1497 syscallarg(timer_t) timerid; 1498 } */ 1499 struct proc *p = l->l_proc; 1500 struct ptimers *pts; 1501 int timerid; 1502 struct itimer *it; 1503 struct ptimer *pt; 1504 1505 timerid = SCARG(uap, timerid); 1506 1507 pts = p->p_timers; 1508 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 1509 return (EINVAL); 1510 itimer_lock(); 1511 if ((it = pts->pts_timers[timerid]) == NULL) { 1512 itimer_unlock(); 1513 return (EINVAL); 1514 } 1515 pt = container_of(it, struct ptimer, pt_itimer); 1516 *retval = pt->pt_poverruns; 1517 if (*retval >= DELAYTIMER_MAX) 1518 *retval = DELAYTIMER_MAX; 1519 itimer_unlock(); 1520 1521 return (0); 1522 } 1523 1524 /* 1525 * sys___getitimer50: 1526 * 1527 * System call to get the time remaining before a BSD timer fires. 1528 */ 1529 int 1530 sys___getitimer50(struct lwp *l, const struct sys___getitimer50_args *uap, 1531 register_t *retval) 1532 { 1533 /* { 1534 syscallarg(int) which; 1535 syscallarg(struct itimerval *) itv; 1536 } */ 1537 struct proc *p = l->l_proc; 1538 struct itimerval aitv; 1539 int error; 1540 1541 memset(&aitv, 0, sizeof(aitv)); 1542 error = dogetitimer(p, SCARG(uap, which), &aitv); 1543 if (error) 1544 return error; 1545 return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval))); 1546 } 1547 1548 int 1549 dogetitimer(struct proc *p, int which, struct itimerval *itvp) 1550 { 1551 struct ptimers *pts; 1552 struct itimer *it; 1553 struct itimerspec its; 1554 1555 if ((u_int)which > ITIMER_MONOTONIC) 1556 return (EINVAL); 1557 1558 itimer_lock(); 1559 pts = p->p_timers; 1560 if (pts == NULL || (it = pts->pts_timers[which]) == NULL) { 1561 timerclear(&itvp->it_value); 1562 timerclear(&itvp->it_interval); 1563 } else { 1564 itimer_gettime(it, &its); 1565 TIMESPEC_TO_TIMEVAL(&itvp->it_value, &its.it_value); 1566 TIMESPEC_TO_TIMEVAL(&itvp->it_interval, &its.it_interval); 1567 } 1568 itimer_unlock(); 1569 1570 return 0; 1571 } 1572 1573 /* 1574 * sys___setitimer50: 1575 * 1576 * System call to set/arm a BSD timer. 1577 */ 1578 int 1579 sys___setitimer50(struct lwp *l, const struct sys___setitimer50_args *uap, 1580 register_t *retval) 1581 { 1582 /* { 1583 syscallarg(int) which; 1584 syscallarg(const struct itimerval *) itv; 1585 syscallarg(struct itimerval *) oitv; 1586 } */ 1587 struct proc *p = l->l_proc; 1588 int which = SCARG(uap, which); 1589 struct sys___getitimer50_args getargs; 1590 const struct itimerval *itvp; 1591 struct itimerval aitv; 1592 int error; 1593 1594 itvp = SCARG(uap, itv); 1595 if (itvp && 1596 (error = copyin(itvp, &aitv, sizeof(struct itimerval))) != 0) 1597 return (error); 1598 if (SCARG(uap, oitv) != NULL) { 1599 SCARG(&getargs, which) = which; 1600 SCARG(&getargs, itv) = SCARG(uap, oitv); 1601 if ((error = sys___getitimer50(l, &getargs, retval)) != 0) 1602 return (error); 1603 } 1604 if (itvp == 0) 1605 return (0); 1606 1607 return dosetitimer(p, which, &aitv); 1608 } 1609 1610 int 1611 dosetitimer(struct proc *p, int which, struct itimerval *itvp) 1612 { 1613 struct timespec now; 1614 struct ptimers *pts; 1615 struct ptimer *spare; 1616 struct itimer *it; 1617 struct itlist *itl; 1618 int error; 1619 1620 if ((u_int)which > ITIMER_MONOTONIC) 1621 return (EINVAL); 1622 if (itimerfix(&itvp->it_value) || itimerfix(&itvp->it_interval)) 1623 return (EINVAL); 1624 1625 /* 1626 * Don't bother allocating data structures if the process just 1627 * wants to clear the timer. 1628 */ 1629 spare = NULL; 1630 pts = p->p_timers; 1631 retry: 1632 if (!timerisset(&itvp->it_value) && (pts == NULL || 1633 pts->pts_timers[which] == NULL)) 1634 return (0); 1635 if (pts == NULL) 1636 pts = ptimers_alloc(p); 1637 itimer_lock(); 1638 restart: 1639 it = pts->pts_timers[which]; 1640 if (it == NULL) { 1641 struct ptimer *pt; 1642 1643 if (spare == NULL) { 1644 itimer_unlock(); 1645 spare = kmem_zalloc(sizeof(*spare), KM_SLEEP); 1646 goto retry; 1647 } 1648 pt = spare; 1649 spare = NULL; 1650 1651 it = &pt->pt_itimer; 1652 pt->pt_ev.sigev_notify = SIGEV_SIGNAL; 1653 pt->pt_ev.sigev_value.sival_int = which; 1654 1655 switch (which) { 1656 case ITIMER_REAL: 1657 case ITIMER_MONOTONIC: 1658 itl = NULL; 1659 pt->pt_ev.sigev_signo = SIGALRM; 1660 break; 1661 case ITIMER_VIRTUAL: 1662 itl = &pts->pts_virtual; 1663 pt->pt_ev.sigev_signo = SIGVTALRM; 1664 break; 1665 case ITIMER_PROF: 1666 itl = &pts->pts_prof; 1667 pt->pt_ev.sigev_signo = SIGPROF; 1668 break; 1669 default: 1670 panic("%s: can't happen %d", __func__, which); 1671 } 1672 itimer_init(it, &ptimer_itimer_ops, which, itl); 1673 pt->pt_proc = p; 1674 pt->pt_entry = which; 1675 1676 pts->pts_timers[which] = it; 1677 } 1678 1679 TIMEVAL_TO_TIMESPEC(&itvp->it_value, &it->it_time.it_value); 1680 TIMEVAL_TO_TIMESPEC(&itvp->it_interval, &it->it_time.it_interval); 1681 1682 if (timespecisset(&it->it_time.it_value)) { 1683 /* Convert to absolute time */ 1684 /* XXX need to wrap in splclock for timecounters case? */ 1685 switch (which) { 1686 case ITIMER_REAL: 1687 getnanotime(&now); 1688 timespecadd(&it->it_time.it_value, &now, 1689 &it->it_time.it_value); 1690 break; 1691 case ITIMER_MONOTONIC: 1692 getnanouptime(&now); 1693 timespecadd(&it->it_time.it_value, &now, 1694 &it->it_time.it_value); 1695 break; 1696 default: 1697 break; 1698 } 1699 } 1700 error = itimer_settime(it); 1701 if (error == ERESTART) { 1702 KASSERT(!CLOCK_VIRTUAL_P(it->it_clockid)); 1703 goto restart; 1704 } 1705 KASSERT(error == 0); 1706 itimer_unlock(); 1707 if (spare != NULL) 1708 kmem_free(spare, sizeof(*spare)); 1709 1710 return (0); 1711 } 1712 1713 /* 1714 * ptimer_tick: 1715 * 1716 * Called from hardclock() to decrement per-process virtual timers. 1717 */ 1718 void 1719 ptimer_tick(lwp_t *l, bool user) 1720 { 1721 struct ptimers *pts; 1722 struct itimer *it; 1723 proc_t *p; 1724 1725 p = l->l_proc; 1726 if (p->p_timers == NULL) 1727 return; 1728 1729 itimer_lock(); 1730 if ((pts = l->l_proc->p_timers) != NULL) { 1731 /* 1732 * Run current process's virtual and profile time, as needed. 1733 */ 1734 if (user && (it = LIST_FIRST(&pts->pts_virtual)) != NULL) 1735 if (itimer_decr(it, tick * 1000)) 1736 (*it->it_ops->ito_fire)(it); 1737 if ((it = LIST_FIRST(&pts->pts_prof)) != NULL) 1738 if (itimer_decr(it, tick * 1000)) 1739 (*it->it_ops->ito_fire)(it); 1740 } 1741 itimer_unlock(); 1742 } 1743 1744 /* 1745 * ptimer_intr: 1746 * 1747 * Software interrupt handler for processing per-process 1748 * timer expiration. 1749 */ 1750 static void 1751 ptimer_intr(void *cookie) 1752 { 1753 ksiginfo_t ksi; 1754 struct itimer *it; 1755 struct ptimer *pt; 1756 proc_t *p; 1757 1758 mutex_enter(&proc_lock); 1759 itimer_lock(); 1760 while ((pt = TAILQ_FIRST(&ptimer_queue)) != NULL) { 1761 it = &pt->pt_itimer; 1762 1763 TAILQ_REMOVE(&ptimer_queue, pt, pt_chain); 1764 KASSERT(pt->pt_queued); 1765 pt->pt_queued = false; 1766 1767 p = pt->pt_proc; 1768 if (p->p_timers == NULL) { 1769 /* Process is dying. */ 1770 continue; 1771 } 1772 if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL) { 1773 continue; 1774 } 1775 if (sigismember(&p->p_sigpend.sp_set, pt->pt_ev.sigev_signo)) { 1776 it->it_overruns++; 1777 continue; 1778 } 1779 1780 KSI_INIT(&ksi); 1781 ksi.ksi_signo = pt->pt_ev.sigev_signo; 1782 ksi.ksi_code = SI_TIMER; 1783 ksi.ksi_value = pt->pt_ev.sigev_value; 1784 pt->pt_poverruns = it->it_overruns; 1785 it->it_overruns = 0; 1786 itimer_unlock(); 1787 kpsignal(p, &ksi, NULL); 1788 itimer_lock(); 1789 } 1790 itimer_unlock(); 1791 mutex_exit(&proc_lock); 1792 } 1793