1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2015, 2016 The FreeBSD Foundation 5 * Copyright (c) 2004, David Xu <davidxu@freebsd.org> 6 * Copyright (c) 2002, Jeffrey Roberson <jeff@freebsd.org> 7 * All rights reserved. 8 * 9 * Portions of this software were developed by Konstantin Belousov 10 * under sponsorship from the FreeBSD Foundation. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice unmodified, this list of conditions, and the following 17 * disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 #include "opt_umtx_profiling.h" 36 37 #include <sys/param.h> 38 #include <sys/kernel.h> 39 #include <sys/fcntl.h> 40 #include <sys/file.h> 41 #include <sys/filedesc.h> 42 #include <sys/limits.h> 43 #include <sys/lock.h> 44 #include <sys/malloc.h> 45 #include <sys/mman.h> 46 #include <sys/mutex.h> 47 #include <sys/priv.h> 48 #include <sys/proc.h> 49 #include <sys/resource.h> 50 #include <sys/resourcevar.h> 51 #include <sys/rwlock.h> 52 #include <sys/sbuf.h> 53 #include <sys/sched.h> 54 #include <sys/smp.h> 55 #include <sys/sysctl.h> 56 #include <sys/systm.h> 57 #include <sys/sysproto.h> 58 #include <sys/syscallsubr.h> 59 #include <sys/taskqueue.h> 60 #include <sys/time.h> 61 #include <sys/eventhandler.h> 62 #include <sys/umtx.h> 63 #include <sys/umtxvar.h> 64 65 #include <security/mac/mac_framework.h> 66 67 #include <vm/vm.h> 68 #include <vm/vm_param.h> 69 #include <vm/pmap.h> 70 #include <vm/uma.h> 71 #include <vm/vm_map.h> 72 #include <vm/vm_object.h> 73 74 #include <machine/atomic.h> 75 #include <machine/cpu.h> 76 77 #include <compat/freebsd32/freebsd32.h> 78 #ifdef COMPAT_FREEBSD32 79 #include <compat/freebsd32/freebsd32_proto.h> 80 #endif 81 82 #define _UMUTEX_TRY 1 83 #define _UMUTEX_WAIT 2 84 85 #ifdef UMTX_PROFILING 86 #define UPROF_PERC_BIGGER(w, f, sw, sf) \ 87 (((w) > (sw)) || ((w) == (sw) && (f) > (sf))) 88 #endif 89 90 #define UMTXQ_LOCKED_ASSERT(uc) mtx_assert(&(uc)->uc_lock, MA_OWNED) 91 #ifdef INVARIANTS 92 #define UMTXQ_ASSERT_LOCKED_BUSY(key) do { \ 93 struct umtxq_chain *uc; \ 94 \ 95 uc = umtxq_getchain(key); \ 96 mtx_assert(&uc->uc_lock, MA_OWNED); \ 97 KASSERT(uc->uc_busy != 0, ("umtx chain is not busy")); \ 98 } while (0) 99 #else 100 #define UMTXQ_ASSERT_LOCKED_BUSY(key) do {} while (0) 101 #endif 102 103 /* 104 * Don't propagate time-sharing priority, there is a security reason, 105 * a user can simply introduce PI-mutex, let thread A lock the mutex, 106 * and let another thread B block on the mutex, because B is 107 * sleeping, its priority will be boosted, this causes A's priority to 108 * be boosted via priority propagating too and will never be lowered even 109 * if it is using 100%CPU, this is unfair to other processes. 110 */ 111 112 #define UPRI(td) (((td)->td_user_pri >= PRI_MIN_TIMESHARE &&\ 113 (td)->td_user_pri <= PRI_MAX_TIMESHARE) ?\ 114 PRI_MAX_TIMESHARE : (td)->td_user_pri) 115 116 #define GOLDEN_RATIO_PRIME 2654404609U 117 #ifndef UMTX_CHAINS 118 #define UMTX_CHAINS 512 119 #endif 120 #define UMTX_SHIFTS (__WORD_BIT - 9) 121 122 #define GET_SHARE(flags) \ 123 (((flags) & USYNC_PROCESS_SHARED) == 0 ? THREAD_SHARE : PROCESS_SHARE) 124 125 #define BUSY_SPINS 200 126 127 struct umtx_copyops { 128 int (*copyin_timeout)(const void *uaddr, struct timespec *tsp); 129 int (*copyin_umtx_time)(const void *uaddr, size_t size, 130 struct _umtx_time *tp); 131 int (*copyin_robust_lists)(const void *uaddr, size_t size, 132 struct umtx_robust_lists_params *rbp); 133 int (*copyout_timeout)(void *uaddr, size_t size, 134 struct timespec *tsp); 135 const size_t timespec_sz; 136 const size_t umtx_time_sz; 137 const bool compat32; 138 }; 139 140 _Static_assert(sizeof(struct umutex) == sizeof(struct umutex32), "umutex32"); 141 _Static_assert(__offsetof(struct umutex, m_spare[0]) == 142 __offsetof(struct umutex32, m_spare[0]), "m_spare32"); 143 144 int umtx_shm_vnobj_persistent = 0; 145 SYSCTL_INT(_kern_ipc, OID_AUTO, umtx_vnode_persistent, CTLFLAG_RWTUN, 146 &umtx_shm_vnobj_persistent, 0, 147 "False forces destruction of umtx attached to file, on last close"); 148 static int umtx_max_rb = 1000; 149 SYSCTL_INT(_kern_ipc, OID_AUTO, umtx_max_robust, CTLFLAG_RWTUN, 150 &umtx_max_rb, 0, 151 "Maximum number of robust mutexes allowed for each thread"); 152 153 static uma_zone_t umtx_pi_zone; 154 static struct umtxq_chain umtxq_chains[2][UMTX_CHAINS]; 155 static MALLOC_DEFINE(M_UMTX, "umtx", "UMTX queue memory"); 156 static int umtx_pi_allocated; 157 158 static SYSCTL_NODE(_debug, OID_AUTO, umtx, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 159 "umtx debug"); 160 SYSCTL_INT(_debug_umtx, OID_AUTO, umtx_pi_allocated, CTLFLAG_RD, 161 &umtx_pi_allocated, 0, "Allocated umtx_pi"); 162 static int umtx_verbose_rb = 1; 163 SYSCTL_INT(_debug_umtx, OID_AUTO, robust_faults_verbose, CTLFLAG_RWTUN, 164 &umtx_verbose_rb, 0, 165 ""); 166 167 #ifdef UMTX_PROFILING 168 static long max_length; 169 SYSCTL_LONG(_debug_umtx, OID_AUTO, max_length, CTLFLAG_RD, &max_length, 0, "max_length"); 170 static SYSCTL_NODE(_debug_umtx, OID_AUTO, chains, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 171 "umtx chain stats"); 172 #endif 173 174 static inline void umtx_abs_timeout_init2(struct umtx_abs_timeout *timo, 175 const struct _umtx_time *umtxtime); 176 177 static void umtx_shm_init(void); 178 static void umtxq_sysinit(void *); 179 static void umtxq_hash(struct umtx_key *key); 180 static int do_unlock_pp(struct thread *td, struct umutex *m, uint32_t flags, 181 bool rb); 182 static void umtx_thread_cleanup(struct thread *td); 183 SYSINIT(umtx, SI_SUB_EVENTHANDLER+1, SI_ORDER_MIDDLE, umtxq_sysinit, NULL); 184 185 #define umtxq_signal(key, nwake) umtxq_signal_queue((key), (nwake), UMTX_SHARED_QUEUE) 186 187 static struct mtx umtx_lock; 188 189 #ifdef UMTX_PROFILING 190 static void 191 umtx_init_profiling(void) 192 { 193 struct sysctl_oid *chain_oid; 194 char chain_name[10]; 195 int i; 196 197 for (i = 0; i < UMTX_CHAINS; ++i) { 198 snprintf(chain_name, sizeof(chain_name), "%d", i); 199 chain_oid = SYSCTL_ADD_NODE(NULL, 200 SYSCTL_STATIC_CHILDREN(_debug_umtx_chains), OID_AUTO, 201 chain_name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 202 "umtx hash stats"); 203 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(chain_oid), OID_AUTO, 204 "max_length0", CTLFLAG_RD, &umtxq_chains[0][i].max_length, 0, NULL); 205 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(chain_oid), OID_AUTO, 206 "max_length1", CTLFLAG_RD, &umtxq_chains[1][i].max_length, 0, NULL); 207 } 208 } 209 210 static int 211 sysctl_debug_umtx_chains_peaks(SYSCTL_HANDLER_ARGS) 212 { 213 char buf[512]; 214 struct sbuf sb; 215 struct umtxq_chain *uc; 216 u_int fract, i, j, tot, whole; 217 u_int sf0, sf1, sf2, sf3, sf4; 218 u_int si0, si1, si2, si3, si4; 219 u_int sw0, sw1, sw2, sw3, sw4; 220 221 sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN); 222 for (i = 0; i < 2; i++) { 223 tot = 0; 224 for (j = 0; j < UMTX_CHAINS; ++j) { 225 uc = &umtxq_chains[i][j]; 226 mtx_lock(&uc->uc_lock); 227 tot += uc->max_length; 228 mtx_unlock(&uc->uc_lock); 229 } 230 if (tot == 0) 231 sbuf_printf(&sb, "%u) Empty ", i); 232 else { 233 sf0 = sf1 = sf2 = sf3 = sf4 = 0; 234 si0 = si1 = si2 = si3 = si4 = 0; 235 sw0 = sw1 = sw2 = sw3 = sw4 = 0; 236 for (j = 0; j < UMTX_CHAINS; j++) { 237 uc = &umtxq_chains[i][j]; 238 mtx_lock(&uc->uc_lock); 239 whole = uc->max_length * 100; 240 mtx_unlock(&uc->uc_lock); 241 fract = (whole % tot) * 100; 242 if (UPROF_PERC_BIGGER(whole, fract, sw0, sf0)) { 243 sf0 = fract; 244 si0 = j; 245 sw0 = whole; 246 } else if (UPROF_PERC_BIGGER(whole, fract, sw1, 247 sf1)) { 248 sf1 = fract; 249 si1 = j; 250 sw1 = whole; 251 } else if (UPROF_PERC_BIGGER(whole, fract, sw2, 252 sf2)) { 253 sf2 = fract; 254 si2 = j; 255 sw2 = whole; 256 } else if (UPROF_PERC_BIGGER(whole, fract, sw3, 257 sf3)) { 258 sf3 = fract; 259 si3 = j; 260 sw3 = whole; 261 } else if (UPROF_PERC_BIGGER(whole, fract, sw4, 262 sf4)) { 263 sf4 = fract; 264 si4 = j; 265 sw4 = whole; 266 } 267 } 268 sbuf_printf(&sb, "queue %u:\n", i); 269 sbuf_printf(&sb, "1st: %u.%u%% idx: %u\n", sw0 / tot, 270 sf0 / tot, si0); 271 sbuf_printf(&sb, "2nd: %u.%u%% idx: %u\n", sw1 / tot, 272 sf1 / tot, si1); 273 sbuf_printf(&sb, "3rd: %u.%u%% idx: %u\n", sw2 / tot, 274 sf2 / tot, si2); 275 sbuf_printf(&sb, "4th: %u.%u%% idx: %u\n", sw3 / tot, 276 sf3 / tot, si3); 277 sbuf_printf(&sb, "5th: %u.%u%% idx: %u\n", sw4 / tot, 278 sf4 / tot, si4); 279 } 280 } 281 sbuf_trim(&sb); 282 sbuf_finish(&sb); 283 sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req); 284 sbuf_delete(&sb); 285 return (0); 286 } 287 288 static int 289 sysctl_debug_umtx_chains_clear(SYSCTL_HANDLER_ARGS) 290 { 291 struct umtxq_chain *uc; 292 u_int i, j; 293 int clear, error; 294 295 clear = 0; 296 error = sysctl_handle_int(oidp, &clear, 0, req); 297 if (error != 0 || req->newptr == NULL) 298 return (error); 299 300 if (clear != 0) { 301 for (i = 0; i < 2; ++i) { 302 for (j = 0; j < UMTX_CHAINS; ++j) { 303 uc = &umtxq_chains[i][j]; 304 mtx_lock(&uc->uc_lock); 305 uc->length = 0; 306 uc->max_length = 0; 307 mtx_unlock(&uc->uc_lock); 308 } 309 } 310 } 311 return (0); 312 } 313 314 SYSCTL_PROC(_debug_umtx_chains, OID_AUTO, clear, 315 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0, 316 sysctl_debug_umtx_chains_clear, "I", 317 "Clear umtx chains statistics"); 318 SYSCTL_PROC(_debug_umtx_chains, OID_AUTO, peaks, 319 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, 320 sysctl_debug_umtx_chains_peaks, "A", 321 "Highest peaks in chains max length"); 322 #endif 323 324 static void 325 umtxq_sysinit(void *arg __unused) 326 { 327 int i, j; 328 329 umtx_pi_zone = uma_zcreate("umtx pi", sizeof(struct umtx_pi), 330 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 331 for (i = 0; i < 2; ++i) { 332 for (j = 0; j < UMTX_CHAINS; ++j) { 333 mtx_init(&umtxq_chains[i][j].uc_lock, "umtxql", NULL, 334 MTX_DEF | MTX_DUPOK); 335 LIST_INIT(&umtxq_chains[i][j].uc_queue[0]); 336 LIST_INIT(&umtxq_chains[i][j].uc_queue[1]); 337 LIST_INIT(&umtxq_chains[i][j].uc_spare_queue); 338 TAILQ_INIT(&umtxq_chains[i][j].uc_pi_list); 339 umtxq_chains[i][j].uc_busy = 0; 340 umtxq_chains[i][j].uc_waiters = 0; 341 #ifdef UMTX_PROFILING 342 umtxq_chains[i][j].length = 0; 343 umtxq_chains[i][j].max_length = 0; 344 #endif 345 } 346 } 347 #ifdef UMTX_PROFILING 348 umtx_init_profiling(); 349 #endif 350 mtx_init(&umtx_lock, "umtx lock", NULL, MTX_DEF); 351 umtx_shm_init(); 352 } 353 354 struct umtx_q * 355 umtxq_alloc(void) 356 { 357 struct umtx_q *uq; 358 359 uq = malloc(sizeof(struct umtx_q), M_UMTX, M_WAITOK | M_ZERO); 360 uq->uq_spare_queue = malloc(sizeof(struct umtxq_queue), M_UMTX, 361 M_WAITOK | M_ZERO); 362 TAILQ_INIT(&uq->uq_spare_queue->head); 363 TAILQ_INIT(&uq->uq_pi_contested); 364 uq->uq_inherited_pri = PRI_MAX; 365 return (uq); 366 } 367 368 void 369 umtxq_free(struct umtx_q *uq) 370 { 371 372 MPASS(uq->uq_spare_queue != NULL); 373 free(uq->uq_spare_queue, M_UMTX); 374 free(uq, M_UMTX); 375 } 376 377 static inline void 378 umtxq_hash(struct umtx_key *key) 379 { 380 unsigned n; 381 382 n = (uintptr_t)key->info.both.a + key->info.both.b; 383 key->hash = ((n * GOLDEN_RATIO_PRIME) >> UMTX_SHIFTS) % UMTX_CHAINS; 384 } 385 386 struct umtxq_chain * 387 umtxq_getchain(struct umtx_key *key) 388 { 389 390 if (key->type <= TYPE_SEM) 391 return (&umtxq_chains[1][key->hash]); 392 return (&umtxq_chains[0][key->hash]); 393 } 394 395 /* 396 * Set chain to busy state when following operation 397 * may be blocked (kernel mutex can not be used). 398 */ 399 void 400 umtxq_busy(struct umtx_key *key) 401 { 402 struct umtxq_chain *uc; 403 404 uc = umtxq_getchain(key); 405 mtx_assert(&uc->uc_lock, MA_OWNED); 406 if (uc->uc_busy) { 407 #ifdef SMP 408 if (smp_cpus > 1) { 409 int count = BUSY_SPINS; 410 if (count > 0) { 411 umtxq_unlock(key); 412 while (uc->uc_busy && --count > 0) 413 cpu_spinwait(); 414 umtxq_lock(key); 415 } 416 } 417 #endif 418 while (uc->uc_busy) { 419 uc->uc_waiters++; 420 msleep(uc, &uc->uc_lock, 0, "umtxqb", 0); 421 uc->uc_waiters--; 422 } 423 } 424 uc->uc_busy = 1; 425 } 426 427 /* 428 * Unbusy a chain. 429 */ 430 void 431 umtxq_unbusy(struct umtx_key *key) 432 { 433 struct umtxq_chain *uc; 434 435 uc = umtxq_getchain(key); 436 mtx_assert(&uc->uc_lock, MA_OWNED); 437 KASSERT(uc->uc_busy != 0, ("not busy")); 438 uc->uc_busy = 0; 439 if (uc->uc_waiters) 440 wakeup_one(uc); 441 } 442 443 void 444 umtxq_unbusy_unlocked(struct umtx_key *key) 445 { 446 447 umtxq_lock(key); 448 umtxq_unbusy(key); 449 umtxq_unlock(key); 450 } 451 452 static struct umtxq_queue * 453 umtxq_queue_lookup(struct umtx_key *key, int q) 454 { 455 struct umtxq_queue *uh; 456 struct umtxq_chain *uc; 457 458 uc = umtxq_getchain(key); 459 UMTXQ_LOCKED_ASSERT(uc); 460 LIST_FOREACH(uh, &uc->uc_queue[q], link) { 461 if (umtx_key_match(&uh->key, key)) 462 return (uh); 463 } 464 465 return (NULL); 466 } 467 468 void 469 umtxq_insert_queue(struct umtx_q *uq, int q) 470 { 471 struct umtxq_queue *uh; 472 struct umtxq_chain *uc; 473 474 uc = umtxq_getchain(&uq->uq_key); 475 UMTXQ_LOCKED_ASSERT(uc); 476 KASSERT((uq->uq_flags & UQF_UMTXQ) == 0, ("umtx_q is already on queue")); 477 uh = umtxq_queue_lookup(&uq->uq_key, q); 478 if (uh != NULL) { 479 LIST_INSERT_HEAD(&uc->uc_spare_queue, uq->uq_spare_queue, link); 480 } else { 481 uh = uq->uq_spare_queue; 482 uh->key = uq->uq_key; 483 LIST_INSERT_HEAD(&uc->uc_queue[q], uh, link); 484 #ifdef UMTX_PROFILING 485 uc->length++; 486 if (uc->length > uc->max_length) { 487 uc->max_length = uc->length; 488 if (uc->max_length > max_length) 489 max_length = uc->max_length; 490 } 491 #endif 492 } 493 uq->uq_spare_queue = NULL; 494 495 TAILQ_INSERT_TAIL(&uh->head, uq, uq_link); 496 uh->length++; 497 uq->uq_flags |= UQF_UMTXQ; 498 uq->uq_cur_queue = uh; 499 return; 500 } 501 502 void 503 umtxq_remove_queue(struct umtx_q *uq, int q) 504 { 505 struct umtxq_chain *uc; 506 struct umtxq_queue *uh; 507 508 uc = umtxq_getchain(&uq->uq_key); 509 UMTXQ_LOCKED_ASSERT(uc); 510 if (uq->uq_flags & UQF_UMTXQ) { 511 uh = uq->uq_cur_queue; 512 TAILQ_REMOVE(&uh->head, uq, uq_link); 513 uh->length--; 514 uq->uq_flags &= ~UQF_UMTXQ; 515 if (TAILQ_EMPTY(&uh->head)) { 516 KASSERT(uh->length == 0, 517 ("inconsistent umtxq_queue length")); 518 #ifdef UMTX_PROFILING 519 uc->length--; 520 #endif 521 LIST_REMOVE(uh, link); 522 } else { 523 uh = LIST_FIRST(&uc->uc_spare_queue); 524 KASSERT(uh != NULL, ("uc_spare_queue is empty")); 525 LIST_REMOVE(uh, link); 526 } 527 uq->uq_spare_queue = uh; 528 uq->uq_cur_queue = NULL; 529 } 530 } 531 532 /* 533 * Check if there are multiple waiters 534 */ 535 int 536 umtxq_count(struct umtx_key *key) 537 { 538 struct umtxq_queue *uh; 539 540 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 541 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 542 if (uh != NULL) 543 return (uh->length); 544 return (0); 545 } 546 547 /* 548 * Check if there are multiple PI waiters and returns first 549 * waiter. 550 */ 551 static int 552 umtxq_count_pi(struct umtx_key *key, struct umtx_q **first) 553 { 554 struct umtxq_queue *uh; 555 556 *first = NULL; 557 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 558 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 559 if (uh != NULL) { 560 *first = TAILQ_FIRST(&uh->head); 561 return (uh->length); 562 } 563 return (0); 564 } 565 566 /* 567 * Wake up threads waiting on an userland object by a bit mask. 568 */ 569 int 570 umtxq_signal_mask(struct umtx_key *key, int n_wake, u_int bitset) 571 { 572 struct umtxq_queue *uh; 573 struct umtx_q *uq, *uq_temp; 574 int ret; 575 576 ret = 0; 577 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 578 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 579 if (uh == NULL) 580 return (0); 581 TAILQ_FOREACH_SAFE(uq, &uh->head, uq_link, uq_temp) { 582 if ((uq->uq_bitset & bitset) == 0) 583 continue; 584 umtxq_remove_queue(uq, UMTX_SHARED_QUEUE); 585 wakeup_one(uq); 586 if (++ret >= n_wake) 587 break; 588 } 589 return (ret); 590 } 591 592 /* 593 * Wake up threads waiting on an userland object. 594 */ 595 596 static int 597 umtxq_signal_queue(struct umtx_key *key, int n_wake, int q) 598 { 599 struct umtxq_queue *uh; 600 struct umtx_q *uq; 601 int ret; 602 603 ret = 0; 604 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 605 uh = umtxq_queue_lookup(key, q); 606 if (uh != NULL) { 607 while ((uq = TAILQ_FIRST(&uh->head)) != NULL) { 608 umtxq_remove_queue(uq, q); 609 wakeup(uq); 610 if (++ret >= n_wake) 611 return (ret); 612 } 613 } 614 return (ret); 615 } 616 617 /* 618 * Wake up specified thread. 619 */ 620 static inline void 621 umtxq_signal_thread(struct umtx_q *uq) 622 { 623 624 UMTXQ_LOCKED_ASSERT(umtxq_getchain(&uq->uq_key)); 625 umtxq_remove(uq); 626 wakeup(uq); 627 } 628 629 /* 630 * Wake up a maximum of n_wake threads that are waiting on an userland 631 * object identified by key. The remaining threads are removed from queue 632 * identified by key and added to the queue identified by key2 (requeued). 633 * The n_requeue specifies an upper limit on the number of threads that 634 * are requeued to the second queue. 635 */ 636 int 637 umtxq_requeue(struct umtx_key *key, int n_wake, struct umtx_key *key2, 638 int n_requeue) 639 { 640 struct umtxq_queue *uh; 641 struct umtx_q *uq, *uq_temp; 642 int ret; 643 644 ret = 0; 645 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 646 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key2)); 647 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 648 if (uh == NULL) 649 return (0); 650 TAILQ_FOREACH_SAFE(uq, &uh->head, uq_link, uq_temp) { 651 if (++ret <= n_wake) { 652 umtxq_remove(uq); 653 wakeup_one(uq); 654 } else { 655 umtxq_remove(uq); 656 uq->uq_key = *key2; 657 umtxq_insert(uq); 658 if (ret - n_wake == n_requeue) 659 break; 660 } 661 } 662 return (ret); 663 } 664 665 static inline int 666 tstohz(const struct timespec *tsp) 667 { 668 struct timeval tv; 669 670 TIMESPEC_TO_TIMEVAL(&tv, tsp); 671 return tvtohz(&tv); 672 } 673 674 void 675 umtx_abs_timeout_init(struct umtx_abs_timeout *timo, int clockid, 676 int absolute, const struct timespec *timeout) 677 { 678 679 timo->clockid = clockid; 680 if (!absolute) { 681 timo->is_abs_real = false; 682 kern_clock_gettime(curthread, timo->clockid, &timo->cur); 683 timespecadd(&timo->cur, timeout, &timo->end); 684 } else { 685 timo->end = *timeout; 686 timo->is_abs_real = clockid == CLOCK_REALTIME || 687 clockid == CLOCK_REALTIME_FAST || 688 clockid == CLOCK_REALTIME_PRECISE || 689 clockid == CLOCK_SECOND; 690 } 691 } 692 693 static void 694 umtx_abs_timeout_init2(struct umtx_abs_timeout *timo, 695 const struct _umtx_time *umtxtime) 696 { 697 698 umtx_abs_timeout_init(timo, umtxtime->_clockid, 699 (umtxtime->_flags & UMTX_ABSTIME) != 0, &umtxtime->_timeout); 700 } 701 702 static void 703 umtx_abs_timeout_enforce_min(sbintime_t *sbt) 704 { 705 sbintime_t when, mint; 706 707 mint = curproc->p_umtx_min_timeout; 708 if (__predict_false(mint != 0)) { 709 when = sbinuptime() + mint; 710 if (*sbt < when) 711 *sbt = when; 712 } 713 } 714 715 static int 716 umtx_abs_timeout_getsbt(struct umtx_abs_timeout *timo, sbintime_t *sbt, 717 int *flags) 718 { 719 struct bintime bt, bbt; 720 struct timespec tts; 721 sbintime_t rem; 722 723 switch (timo->clockid) { 724 725 /* Clocks that can be converted into absolute time. */ 726 case CLOCK_REALTIME: 727 case CLOCK_REALTIME_PRECISE: 728 case CLOCK_REALTIME_FAST: 729 case CLOCK_MONOTONIC: 730 case CLOCK_MONOTONIC_PRECISE: 731 case CLOCK_MONOTONIC_FAST: 732 case CLOCK_UPTIME: 733 case CLOCK_UPTIME_PRECISE: 734 case CLOCK_UPTIME_FAST: 735 case CLOCK_SECOND: 736 timespec2bintime(&timo->end, &bt); 737 switch (timo->clockid) { 738 case CLOCK_REALTIME: 739 case CLOCK_REALTIME_PRECISE: 740 case CLOCK_REALTIME_FAST: 741 case CLOCK_SECOND: 742 getboottimebin(&bbt); 743 bintime_sub(&bt, &bbt); 744 break; 745 } 746 if (bt.sec < 0) 747 return (ETIMEDOUT); 748 if (bt.sec >= (SBT_MAX >> 32)) { 749 *sbt = 0; 750 *flags = 0; 751 return (0); 752 } 753 *sbt = bttosbt(bt); 754 umtx_abs_timeout_enforce_min(sbt); 755 756 /* 757 * Check if the absolute time should be aligned to 758 * avoid firing multiple timer events in non-periodic 759 * timer mode. 760 */ 761 switch (timo->clockid) { 762 case CLOCK_REALTIME_FAST: 763 case CLOCK_MONOTONIC_FAST: 764 case CLOCK_UPTIME_FAST: 765 rem = *sbt % tc_tick_sbt; 766 if (__predict_true(rem != 0)) 767 *sbt += tc_tick_sbt - rem; 768 break; 769 case CLOCK_SECOND: 770 rem = *sbt % SBT_1S; 771 if (__predict_true(rem != 0)) 772 *sbt += SBT_1S - rem; 773 break; 774 } 775 *flags = C_ABSOLUTE; 776 return (0); 777 778 /* Clocks that has to be periodically polled. */ 779 case CLOCK_VIRTUAL: 780 case CLOCK_PROF: 781 case CLOCK_THREAD_CPUTIME_ID: 782 case CLOCK_PROCESS_CPUTIME_ID: 783 default: 784 kern_clock_gettime(curthread, timo->clockid, &timo->cur); 785 if (timespeccmp(&timo->end, &timo->cur, <=)) 786 return (ETIMEDOUT); 787 timespecsub(&timo->end, &timo->cur, &tts); 788 *sbt = tick_sbt * tstohz(&tts); 789 *flags = C_HARDCLOCK; 790 return (0); 791 } 792 } 793 794 static uint32_t 795 umtx_unlock_val(uint32_t flags, bool rb) 796 { 797 798 if (rb) 799 return (UMUTEX_RB_OWNERDEAD); 800 else if ((flags & UMUTEX_NONCONSISTENT) != 0) 801 return (UMUTEX_RB_NOTRECOV); 802 else 803 return (UMUTEX_UNOWNED); 804 805 } 806 807 /* 808 * Put thread into sleep state, before sleeping, check if 809 * thread was removed from umtx queue. 810 */ 811 int 812 umtxq_sleep(struct umtx_q *uq, const char *wmesg, 813 struct umtx_abs_timeout *timo) 814 { 815 struct umtxq_chain *uc; 816 sbintime_t sbt = 0; 817 int error, flags = 0; 818 819 uc = umtxq_getchain(&uq->uq_key); 820 UMTXQ_LOCKED_ASSERT(uc); 821 for (;;) { 822 if (!(uq->uq_flags & UQF_UMTXQ)) { 823 error = 0; 824 break; 825 } 826 if (timo != NULL) { 827 if (timo->is_abs_real) 828 curthread->td_rtcgen = 829 atomic_load_acq_int(&rtc_generation); 830 error = umtx_abs_timeout_getsbt(timo, &sbt, &flags); 831 if (error != 0) 832 break; 833 } 834 error = msleep_sbt(uq, &uc->uc_lock, PCATCH | PDROP, wmesg, 835 sbt, 0, flags); 836 uc = umtxq_getchain(&uq->uq_key); 837 mtx_lock(&uc->uc_lock); 838 if (error == EINTR || error == ERESTART) 839 break; 840 if (error == EWOULDBLOCK && (flags & C_ABSOLUTE) != 0) { 841 error = ETIMEDOUT; 842 break; 843 } 844 } 845 846 curthread->td_rtcgen = 0; 847 return (error); 848 } 849 850 /* 851 * Convert userspace address into unique logical address. 852 */ 853 int 854 umtx_key_get(const void *addr, int type, int share, struct umtx_key *key) 855 { 856 struct thread *td = curthread; 857 vm_map_t map; 858 vm_map_entry_t entry; 859 vm_pindex_t pindex; 860 vm_prot_t prot; 861 boolean_t wired; 862 863 key->type = type; 864 if (share == THREAD_SHARE) { 865 key->shared = 0; 866 key->info.private.vs = td->td_proc->p_vmspace; 867 key->info.private.addr = (uintptr_t)addr; 868 } else { 869 MPASS(share == PROCESS_SHARE || share == AUTO_SHARE); 870 map = &td->td_proc->p_vmspace->vm_map; 871 if (vm_map_lookup(&map, (vm_offset_t)addr, VM_PROT_WRITE, 872 &entry, &key->info.shared.object, &pindex, &prot, 873 &wired) != KERN_SUCCESS) { 874 return (EFAULT); 875 } 876 877 if ((share == PROCESS_SHARE) || 878 (share == AUTO_SHARE && 879 VM_INHERIT_SHARE == entry->inheritance)) { 880 key->shared = 1; 881 key->info.shared.offset = (vm_offset_t)addr - 882 entry->start + entry->offset; 883 vm_object_reference(key->info.shared.object); 884 } else { 885 key->shared = 0; 886 key->info.private.vs = td->td_proc->p_vmspace; 887 key->info.private.addr = (uintptr_t)addr; 888 } 889 vm_map_lookup_done(map, entry); 890 } 891 892 umtxq_hash(key); 893 return (0); 894 } 895 896 /* 897 * Release key. 898 */ 899 void 900 umtx_key_release(struct umtx_key *key) 901 { 902 if (key->shared) 903 vm_object_deallocate(key->info.shared.object); 904 } 905 906 #ifdef COMPAT_FREEBSD10 907 /* 908 * Lock a umtx object. 909 */ 910 static int 911 do_lock_umtx(struct thread *td, struct umtx *umtx, u_long id, 912 const struct timespec *timeout) 913 { 914 struct umtx_abs_timeout timo; 915 struct umtx_q *uq; 916 u_long owner; 917 u_long old; 918 int error = 0; 919 920 uq = td->td_umtxq; 921 if (timeout != NULL) 922 umtx_abs_timeout_init(&timo, CLOCK_REALTIME, 0, timeout); 923 924 /* 925 * Care must be exercised when dealing with umtx structure. It 926 * can fault on any access. 927 */ 928 for (;;) { 929 /* 930 * Try the uncontested case. This should be done in userland. 931 */ 932 owner = casuword(&umtx->u_owner, UMTX_UNOWNED, id); 933 934 /* The acquire succeeded. */ 935 if (owner == UMTX_UNOWNED) 936 return (0); 937 938 /* The address was invalid. */ 939 if (owner == -1) 940 return (EFAULT); 941 942 /* If no one owns it but it is contested try to acquire it. */ 943 if (owner == UMTX_CONTESTED) { 944 owner = casuword(&umtx->u_owner, 945 UMTX_CONTESTED, id | UMTX_CONTESTED); 946 947 if (owner == UMTX_CONTESTED) 948 return (0); 949 950 /* The address was invalid. */ 951 if (owner == -1) 952 return (EFAULT); 953 954 error = thread_check_susp(td, false); 955 if (error != 0) 956 break; 957 958 /* If this failed the lock has changed, restart. */ 959 continue; 960 } 961 962 /* 963 * If we caught a signal, we have retried and now 964 * exit immediately. 965 */ 966 if (error != 0) 967 break; 968 969 if ((error = umtx_key_get(umtx, TYPE_SIMPLE_LOCK, 970 AUTO_SHARE, &uq->uq_key)) != 0) 971 return (error); 972 973 umtxq_lock(&uq->uq_key); 974 umtxq_busy(&uq->uq_key); 975 umtxq_insert(uq); 976 umtxq_unbusy(&uq->uq_key); 977 umtxq_unlock(&uq->uq_key); 978 979 /* 980 * Set the contested bit so that a release in user space 981 * knows to use the system call for unlock. If this fails 982 * either some one else has acquired the lock or it has been 983 * released. 984 */ 985 old = casuword(&umtx->u_owner, owner, owner | UMTX_CONTESTED); 986 987 /* The address was invalid. */ 988 if (old == -1) { 989 umtxq_lock(&uq->uq_key); 990 umtxq_remove(uq); 991 umtxq_unlock(&uq->uq_key); 992 umtx_key_release(&uq->uq_key); 993 return (EFAULT); 994 } 995 996 /* 997 * We set the contested bit, sleep. Otherwise the lock changed 998 * and we need to retry or we lost a race to the thread 999 * unlocking the umtx. 1000 */ 1001 umtxq_lock(&uq->uq_key); 1002 if (old == owner) 1003 error = umtxq_sleep(uq, "umtx", timeout == NULL ? NULL : 1004 &timo); 1005 umtxq_remove(uq); 1006 umtxq_unlock(&uq->uq_key); 1007 umtx_key_release(&uq->uq_key); 1008 1009 if (error == 0) 1010 error = thread_check_susp(td, false); 1011 } 1012 1013 if (timeout == NULL) { 1014 /* Mutex locking is restarted if it is interrupted. */ 1015 if (error == EINTR) 1016 error = ERESTART; 1017 } else { 1018 /* Timed-locking is not restarted. */ 1019 if (error == ERESTART) 1020 error = EINTR; 1021 } 1022 return (error); 1023 } 1024 1025 /* 1026 * Unlock a umtx object. 1027 */ 1028 static int 1029 do_unlock_umtx(struct thread *td, struct umtx *umtx, u_long id) 1030 { 1031 struct umtx_key key; 1032 u_long owner; 1033 u_long old; 1034 int error; 1035 int count; 1036 1037 /* 1038 * Make sure we own this mtx. 1039 */ 1040 owner = fuword(__DEVOLATILE(u_long *, &umtx->u_owner)); 1041 if (owner == -1) 1042 return (EFAULT); 1043 1044 if ((owner & ~UMTX_CONTESTED) != id) 1045 return (EPERM); 1046 1047 /* This should be done in userland */ 1048 if ((owner & UMTX_CONTESTED) == 0) { 1049 old = casuword(&umtx->u_owner, owner, UMTX_UNOWNED); 1050 if (old == -1) 1051 return (EFAULT); 1052 if (old == owner) 1053 return (0); 1054 owner = old; 1055 } 1056 1057 /* We should only ever be in here for contested locks */ 1058 if ((error = umtx_key_get(umtx, TYPE_SIMPLE_LOCK, AUTO_SHARE, 1059 &key)) != 0) 1060 return (error); 1061 1062 umtxq_lock(&key); 1063 umtxq_busy(&key); 1064 count = umtxq_count(&key); 1065 umtxq_unlock(&key); 1066 1067 /* 1068 * When unlocking the umtx, it must be marked as unowned if 1069 * there is zero or one thread only waiting for it. 1070 * Otherwise, it must be marked as contested. 1071 */ 1072 old = casuword(&umtx->u_owner, owner, 1073 count <= 1 ? UMTX_UNOWNED : UMTX_CONTESTED); 1074 umtxq_lock(&key); 1075 umtxq_signal(&key,1); 1076 umtxq_unbusy(&key); 1077 umtxq_unlock(&key); 1078 umtx_key_release(&key); 1079 if (old == -1) 1080 return (EFAULT); 1081 if (old != owner) 1082 return (EINVAL); 1083 return (0); 1084 } 1085 1086 #ifdef COMPAT_FREEBSD32 1087 1088 /* 1089 * Lock a umtx object. 1090 */ 1091 static int 1092 do_lock_umtx32(struct thread *td, uint32_t *m, uint32_t id, 1093 const struct timespec *timeout) 1094 { 1095 struct umtx_abs_timeout timo; 1096 struct umtx_q *uq; 1097 uint32_t owner; 1098 uint32_t old; 1099 int error = 0; 1100 1101 uq = td->td_umtxq; 1102 1103 if (timeout != NULL) 1104 umtx_abs_timeout_init(&timo, CLOCK_REALTIME, 0, timeout); 1105 1106 /* 1107 * Care must be exercised when dealing with umtx structure. It 1108 * can fault on any access. 1109 */ 1110 for (;;) { 1111 /* 1112 * Try the uncontested case. This should be done in userland. 1113 */ 1114 owner = casuword32(m, UMUTEX_UNOWNED, id); 1115 1116 /* The acquire succeeded. */ 1117 if (owner == UMUTEX_UNOWNED) 1118 return (0); 1119 1120 /* The address was invalid. */ 1121 if (owner == -1) 1122 return (EFAULT); 1123 1124 /* If no one owns it but it is contested try to acquire it. */ 1125 if (owner == UMUTEX_CONTESTED) { 1126 owner = casuword32(m, 1127 UMUTEX_CONTESTED, id | UMUTEX_CONTESTED); 1128 if (owner == UMUTEX_CONTESTED) 1129 return (0); 1130 1131 /* The address was invalid. */ 1132 if (owner == -1) 1133 return (EFAULT); 1134 1135 error = thread_check_susp(td, false); 1136 if (error != 0) 1137 break; 1138 1139 /* If this failed the lock has changed, restart. */ 1140 continue; 1141 } 1142 1143 /* 1144 * If we caught a signal, we have retried and now 1145 * exit immediately. 1146 */ 1147 if (error != 0) 1148 return (error); 1149 1150 if ((error = umtx_key_get(m, TYPE_SIMPLE_LOCK, 1151 AUTO_SHARE, &uq->uq_key)) != 0) 1152 return (error); 1153 1154 umtxq_lock(&uq->uq_key); 1155 umtxq_busy(&uq->uq_key); 1156 umtxq_insert(uq); 1157 umtxq_unbusy(&uq->uq_key); 1158 umtxq_unlock(&uq->uq_key); 1159 1160 /* 1161 * Set the contested bit so that a release in user space 1162 * knows to use the system call for unlock. If this fails 1163 * either some one else has acquired the lock or it has been 1164 * released. 1165 */ 1166 old = casuword32(m, owner, owner | UMUTEX_CONTESTED); 1167 1168 /* The address was invalid. */ 1169 if (old == -1) { 1170 umtxq_lock(&uq->uq_key); 1171 umtxq_remove(uq); 1172 umtxq_unlock(&uq->uq_key); 1173 umtx_key_release(&uq->uq_key); 1174 return (EFAULT); 1175 } 1176 1177 /* 1178 * We set the contested bit, sleep. Otherwise the lock changed 1179 * and we need to retry or we lost a race to the thread 1180 * unlocking the umtx. 1181 */ 1182 umtxq_lock(&uq->uq_key); 1183 if (old == owner) 1184 error = umtxq_sleep(uq, "umtx", timeout == NULL ? 1185 NULL : &timo); 1186 umtxq_remove(uq); 1187 umtxq_unlock(&uq->uq_key); 1188 umtx_key_release(&uq->uq_key); 1189 1190 if (error == 0) 1191 error = thread_check_susp(td, false); 1192 } 1193 1194 if (timeout == NULL) { 1195 /* Mutex locking is restarted if it is interrupted. */ 1196 if (error == EINTR) 1197 error = ERESTART; 1198 } else { 1199 /* Timed-locking is not restarted. */ 1200 if (error == ERESTART) 1201 error = EINTR; 1202 } 1203 return (error); 1204 } 1205 1206 /* 1207 * Unlock a umtx object. 1208 */ 1209 static int 1210 do_unlock_umtx32(struct thread *td, uint32_t *m, uint32_t id) 1211 { 1212 struct umtx_key key; 1213 uint32_t owner; 1214 uint32_t old; 1215 int error; 1216 int count; 1217 1218 /* 1219 * Make sure we own this mtx. 1220 */ 1221 owner = fuword32(m); 1222 if (owner == -1) 1223 return (EFAULT); 1224 1225 if ((owner & ~UMUTEX_CONTESTED) != id) 1226 return (EPERM); 1227 1228 /* This should be done in userland */ 1229 if ((owner & UMUTEX_CONTESTED) == 0) { 1230 old = casuword32(m, owner, UMUTEX_UNOWNED); 1231 if (old == -1) 1232 return (EFAULT); 1233 if (old == owner) 1234 return (0); 1235 owner = old; 1236 } 1237 1238 /* We should only ever be in here for contested locks */ 1239 if ((error = umtx_key_get(m, TYPE_SIMPLE_LOCK, AUTO_SHARE, 1240 &key)) != 0) 1241 return (error); 1242 1243 umtxq_lock(&key); 1244 umtxq_busy(&key); 1245 count = umtxq_count(&key); 1246 umtxq_unlock(&key); 1247 1248 /* 1249 * When unlocking the umtx, it must be marked as unowned if 1250 * there is zero or one thread only waiting for it. 1251 * Otherwise, it must be marked as contested. 1252 */ 1253 old = casuword32(m, owner, 1254 count <= 1 ? UMUTEX_UNOWNED : UMUTEX_CONTESTED); 1255 umtxq_lock(&key); 1256 umtxq_signal(&key,1); 1257 umtxq_unbusy(&key); 1258 umtxq_unlock(&key); 1259 umtx_key_release(&key); 1260 if (old == -1) 1261 return (EFAULT); 1262 if (old != owner) 1263 return (EINVAL); 1264 return (0); 1265 } 1266 #endif /* COMPAT_FREEBSD32 */ 1267 #endif /* COMPAT_FREEBSD10 */ 1268 1269 /* 1270 * Fetch and compare value, sleep on the address if value is not changed. 1271 */ 1272 static int 1273 do_wait(struct thread *td, void *addr, u_long id, 1274 struct _umtx_time *timeout, int compat32, int is_private) 1275 { 1276 struct umtx_abs_timeout timo; 1277 struct umtx_q *uq; 1278 u_long tmp; 1279 uint32_t tmp32; 1280 int error = 0; 1281 1282 uq = td->td_umtxq; 1283 if ((error = umtx_key_get(addr, TYPE_SIMPLE_WAIT, 1284 is_private ? THREAD_SHARE : AUTO_SHARE, &uq->uq_key)) != 0) 1285 return (error); 1286 1287 if (timeout != NULL) 1288 umtx_abs_timeout_init2(&timo, timeout); 1289 1290 umtxq_lock(&uq->uq_key); 1291 umtxq_insert(uq); 1292 umtxq_unlock(&uq->uq_key); 1293 if (compat32 == 0) { 1294 error = fueword(addr, &tmp); 1295 if (error != 0) 1296 error = EFAULT; 1297 } else { 1298 error = fueword32(addr, &tmp32); 1299 if (error == 0) 1300 tmp = tmp32; 1301 else 1302 error = EFAULT; 1303 } 1304 umtxq_lock(&uq->uq_key); 1305 if (error == 0) { 1306 if (tmp == id) 1307 error = umtxq_sleep(uq, "uwait", timeout == NULL ? 1308 NULL : &timo); 1309 if ((uq->uq_flags & UQF_UMTXQ) == 0) 1310 error = 0; 1311 else 1312 umtxq_remove(uq); 1313 } else if ((uq->uq_flags & UQF_UMTXQ) != 0) { 1314 umtxq_remove(uq); 1315 } 1316 umtxq_unlock(&uq->uq_key); 1317 umtx_key_release(&uq->uq_key); 1318 if (error == ERESTART) 1319 error = EINTR; 1320 return (error); 1321 } 1322 1323 /* 1324 * Wake up threads sleeping on the specified address. 1325 */ 1326 int 1327 kern_umtx_wake(struct thread *td, void *uaddr, int n_wake, int is_private) 1328 { 1329 struct umtx_key key; 1330 int ret; 1331 1332 if ((ret = umtx_key_get(uaddr, TYPE_SIMPLE_WAIT, 1333 is_private ? THREAD_SHARE : AUTO_SHARE, &key)) != 0) 1334 return (ret); 1335 umtxq_lock(&key); 1336 umtxq_signal(&key, n_wake); 1337 umtxq_unlock(&key); 1338 umtx_key_release(&key); 1339 return (0); 1340 } 1341 1342 /* 1343 * Lock PTHREAD_PRIO_NONE protocol POSIX mutex. 1344 */ 1345 static int 1346 do_lock_normal(struct thread *td, struct umutex *m, uint32_t flags, 1347 struct _umtx_time *timeout, int mode) 1348 { 1349 struct umtx_abs_timeout timo; 1350 struct umtx_q *uq; 1351 uint32_t owner, old, id; 1352 int error, rv; 1353 1354 id = td->td_tid; 1355 uq = td->td_umtxq; 1356 error = 0; 1357 if (timeout != NULL) 1358 umtx_abs_timeout_init2(&timo, timeout); 1359 1360 /* 1361 * Care must be exercised when dealing with umtx structure. It 1362 * can fault on any access. 1363 */ 1364 for (;;) { 1365 rv = fueword32(&m->m_owner, &owner); 1366 if (rv == -1) 1367 return (EFAULT); 1368 if (mode == _UMUTEX_WAIT) { 1369 if (owner == UMUTEX_UNOWNED || 1370 owner == UMUTEX_CONTESTED || 1371 owner == UMUTEX_RB_OWNERDEAD || 1372 owner == UMUTEX_RB_NOTRECOV) 1373 return (0); 1374 } else { 1375 /* 1376 * Robust mutex terminated. Kernel duty is to 1377 * return EOWNERDEAD to the userspace. The 1378 * umutex.m_flags UMUTEX_NONCONSISTENT is set 1379 * by the common userspace code. 1380 */ 1381 if (owner == UMUTEX_RB_OWNERDEAD) { 1382 rv = casueword32(&m->m_owner, 1383 UMUTEX_RB_OWNERDEAD, &owner, 1384 id | UMUTEX_CONTESTED); 1385 if (rv == -1) 1386 return (EFAULT); 1387 if (rv == 0) { 1388 MPASS(owner == UMUTEX_RB_OWNERDEAD); 1389 return (EOWNERDEAD); /* success */ 1390 } 1391 MPASS(rv == 1); 1392 rv = thread_check_susp(td, false); 1393 if (rv != 0) 1394 return (rv); 1395 continue; 1396 } 1397 if (owner == UMUTEX_RB_NOTRECOV) 1398 return (ENOTRECOVERABLE); 1399 1400 /* 1401 * Try the uncontested case. This should be 1402 * done in userland. 1403 */ 1404 rv = casueword32(&m->m_owner, UMUTEX_UNOWNED, 1405 &owner, id); 1406 /* The address was invalid. */ 1407 if (rv == -1) 1408 return (EFAULT); 1409 1410 /* The acquire succeeded. */ 1411 if (rv == 0) { 1412 MPASS(owner == UMUTEX_UNOWNED); 1413 return (0); 1414 } 1415 1416 /* 1417 * If no one owns it but it is contested try 1418 * to acquire it. 1419 */ 1420 MPASS(rv == 1); 1421 if (owner == UMUTEX_CONTESTED) { 1422 rv = casueword32(&m->m_owner, 1423 UMUTEX_CONTESTED, &owner, 1424 id | UMUTEX_CONTESTED); 1425 /* The address was invalid. */ 1426 if (rv == -1) 1427 return (EFAULT); 1428 if (rv == 0) { 1429 MPASS(owner == UMUTEX_CONTESTED); 1430 return (0); 1431 } 1432 if (rv == 1) { 1433 rv = thread_check_susp(td, false); 1434 if (rv != 0) 1435 return (rv); 1436 } 1437 1438 /* 1439 * If this failed the lock has 1440 * changed, restart. 1441 */ 1442 continue; 1443 } 1444 1445 /* rv == 1 but not contested, likely store failure */ 1446 rv = thread_check_susp(td, false); 1447 if (rv != 0) 1448 return (rv); 1449 } 1450 1451 if (mode == _UMUTEX_TRY) 1452 return (EBUSY); 1453 1454 /* 1455 * If we caught a signal, we have retried and now 1456 * exit immediately. 1457 */ 1458 if (error != 0) 1459 return (error); 1460 1461 if ((error = umtx_key_get(m, TYPE_NORMAL_UMUTEX, 1462 GET_SHARE(flags), &uq->uq_key)) != 0) 1463 return (error); 1464 1465 umtxq_lock(&uq->uq_key); 1466 umtxq_busy(&uq->uq_key); 1467 umtxq_insert(uq); 1468 umtxq_unlock(&uq->uq_key); 1469 1470 /* 1471 * Set the contested bit so that a release in user space 1472 * knows to use the system call for unlock. If this fails 1473 * either some one else has acquired the lock or it has been 1474 * released. 1475 */ 1476 rv = casueword32(&m->m_owner, owner, &old, 1477 owner | UMUTEX_CONTESTED); 1478 1479 /* The address was invalid or casueword failed to store. */ 1480 if (rv == -1 || rv == 1) { 1481 umtxq_lock(&uq->uq_key); 1482 umtxq_remove(uq); 1483 umtxq_unbusy(&uq->uq_key); 1484 umtxq_unlock(&uq->uq_key); 1485 umtx_key_release(&uq->uq_key); 1486 if (rv == -1) 1487 return (EFAULT); 1488 if (rv == 1) { 1489 rv = thread_check_susp(td, false); 1490 if (rv != 0) 1491 return (rv); 1492 } 1493 continue; 1494 } 1495 1496 /* 1497 * We set the contested bit, sleep. Otherwise the lock changed 1498 * and we need to retry or we lost a race to the thread 1499 * unlocking the umtx. 1500 */ 1501 umtxq_lock(&uq->uq_key); 1502 umtxq_unbusy(&uq->uq_key); 1503 MPASS(old == owner); 1504 error = umtxq_sleep(uq, "umtxn", timeout == NULL ? 1505 NULL : &timo); 1506 umtxq_remove(uq); 1507 umtxq_unlock(&uq->uq_key); 1508 umtx_key_release(&uq->uq_key); 1509 1510 if (error == 0) 1511 error = thread_check_susp(td, false); 1512 } 1513 1514 return (0); 1515 } 1516 1517 /* 1518 * Unlock PTHREAD_PRIO_NONE protocol POSIX mutex. 1519 */ 1520 static int 1521 do_unlock_normal(struct thread *td, struct umutex *m, uint32_t flags, bool rb) 1522 { 1523 struct umtx_key key; 1524 uint32_t owner, old, id, newlock; 1525 int error, count; 1526 1527 id = td->td_tid; 1528 1529 again: 1530 /* 1531 * Make sure we own this mtx. 1532 */ 1533 error = fueword32(&m->m_owner, &owner); 1534 if (error == -1) 1535 return (EFAULT); 1536 1537 if ((owner & ~UMUTEX_CONTESTED) != id) 1538 return (EPERM); 1539 1540 newlock = umtx_unlock_val(flags, rb); 1541 if ((owner & UMUTEX_CONTESTED) == 0) { 1542 error = casueword32(&m->m_owner, owner, &old, newlock); 1543 if (error == -1) 1544 return (EFAULT); 1545 if (error == 1) { 1546 error = thread_check_susp(td, false); 1547 if (error != 0) 1548 return (error); 1549 goto again; 1550 } 1551 MPASS(old == owner); 1552 return (0); 1553 } 1554 1555 /* We should only ever be in here for contested locks */ 1556 if ((error = umtx_key_get(m, TYPE_NORMAL_UMUTEX, GET_SHARE(flags), 1557 &key)) != 0) 1558 return (error); 1559 1560 umtxq_lock(&key); 1561 umtxq_busy(&key); 1562 count = umtxq_count(&key); 1563 umtxq_unlock(&key); 1564 1565 /* 1566 * When unlocking the umtx, it must be marked as unowned if 1567 * there is zero or one thread only waiting for it. 1568 * Otherwise, it must be marked as contested. 1569 */ 1570 if (count > 1) 1571 newlock |= UMUTEX_CONTESTED; 1572 error = casueword32(&m->m_owner, owner, &old, newlock); 1573 umtxq_lock(&key); 1574 umtxq_signal(&key, 1); 1575 umtxq_unbusy(&key); 1576 umtxq_unlock(&key); 1577 umtx_key_release(&key); 1578 if (error == -1) 1579 return (EFAULT); 1580 if (error == 1) { 1581 if (old != owner) 1582 return (EINVAL); 1583 error = thread_check_susp(td, false); 1584 if (error != 0) 1585 return (error); 1586 goto again; 1587 } 1588 return (0); 1589 } 1590 1591 /* 1592 * Check if the mutex is available and wake up a waiter, 1593 * only for simple mutex. 1594 */ 1595 static int 1596 do_wake_umutex(struct thread *td, struct umutex *m) 1597 { 1598 struct umtx_key key; 1599 uint32_t owner; 1600 uint32_t flags; 1601 int error; 1602 int count; 1603 1604 again: 1605 error = fueword32(&m->m_owner, &owner); 1606 if (error == -1) 1607 return (EFAULT); 1608 1609 if ((owner & ~UMUTEX_CONTESTED) != 0 && owner != UMUTEX_RB_OWNERDEAD && 1610 owner != UMUTEX_RB_NOTRECOV) 1611 return (0); 1612 1613 error = fueword32(&m->m_flags, &flags); 1614 if (error == -1) 1615 return (EFAULT); 1616 1617 /* We should only ever be in here for contested locks */ 1618 if ((error = umtx_key_get(m, TYPE_NORMAL_UMUTEX, GET_SHARE(flags), 1619 &key)) != 0) 1620 return (error); 1621 1622 umtxq_lock(&key); 1623 umtxq_busy(&key); 1624 count = umtxq_count(&key); 1625 umtxq_unlock(&key); 1626 1627 if (count <= 1 && owner != UMUTEX_RB_OWNERDEAD && 1628 owner != UMUTEX_RB_NOTRECOV) { 1629 error = casueword32(&m->m_owner, UMUTEX_CONTESTED, &owner, 1630 UMUTEX_UNOWNED); 1631 if (error == -1) { 1632 error = EFAULT; 1633 } else if (error == 1) { 1634 umtxq_lock(&key); 1635 umtxq_unbusy(&key); 1636 umtxq_unlock(&key); 1637 umtx_key_release(&key); 1638 error = thread_check_susp(td, false); 1639 if (error != 0) 1640 return (error); 1641 goto again; 1642 } 1643 } 1644 1645 umtxq_lock(&key); 1646 if (error == 0 && count != 0) { 1647 MPASS((owner & ~UMUTEX_CONTESTED) == 0 || 1648 owner == UMUTEX_RB_OWNERDEAD || 1649 owner == UMUTEX_RB_NOTRECOV); 1650 umtxq_signal(&key, 1); 1651 } 1652 umtxq_unbusy(&key); 1653 umtxq_unlock(&key); 1654 umtx_key_release(&key); 1655 return (error); 1656 } 1657 1658 /* 1659 * Check if the mutex has waiters and tries to fix contention bit. 1660 */ 1661 static int 1662 do_wake2_umutex(struct thread *td, struct umutex *m, uint32_t flags) 1663 { 1664 struct umtx_key key; 1665 uint32_t owner, old; 1666 int type; 1667 int error; 1668 int count; 1669 1670 switch (flags & (UMUTEX_PRIO_INHERIT | UMUTEX_PRIO_PROTECT | 1671 UMUTEX_ROBUST)) { 1672 case 0: 1673 case UMUTEX_ROBUST: 1674 type = TYPE_NORMAL_UMUTEX; 1675 break; 1676 case UMUTEX_PRIO_INHERIT: 1677 type = TYPE_PI_UMUTEX; 1678 break; 1679 case (UMUTEX_PRIO_INHERIT | UMUTEX_ROBUST): 1680 type = TYPE_PI_ROBUST_UMUTEX; 1681 break; 1682 case UMUTEX_PRIO_PROTECT: 1683 type = TYPE_PP_UMUTEX; 1684 break; 1685 case (UMUTEX_PRIO_PROTECT | UMUTEX_ROBUST): 1686 type = TYPE_PP_ROBUST_UMUTEX; 1687 break; 1688 default: 1689 return (EINVAL); 1690 } 1691 if ((error = umtx_key_get(m, type, GET_SHARE(flags), &key)) != 0) 1692 return (error); 1693 1694 owner = 0; 1695 umtxq_lock(&key); 1696 umtxq_busy(&key); 1697 count = umtxq_count(&key); 1698 umtxq_unlock(&key); 1699 1700 error = fueword32(&m->m_owner, &owner); 1701 if (error == -1) 1702 error = EFAULT; 1703 1704 /* 1705 * Only repair contention bit if there is a waiter, this means 1706 * the mutex is still being referenced by userland code, 1707 * otherwise don't update any memory. 1708 */ 1709 while (error == 0 && (owner & UMUTEX_CONTESTED) == 0 && 1710 (count > 1 || (count == 1 && (owner & ~UMUTEX_CONTESTED) != 0))) { 1711 error = casueword32(&m->m_owner, owner, &old, 1712 owner | UMUTEX_CONTESTED); 1713 if (error == -1) { 1714 error = EFAULT; 1715 break; 1716 } 1717 if (error == 0) { 1718 MPASS(old == owner); 1719 break; 1720 } 1721 owner = old; 1722 error = thread_check_susp(td, false); 1723 } 1724 1725 umtxq_lock(&key); 1726 if (error == EFAULT) { 1727 umtxq_signal(&key, INT_MAX); 1728 } else if (count != 0 && ((owner & ~UMUTEX_CONTESTED) == 0 || 1729 owner == UMUTEX_RB_OWNERDEAD || owner == UMUTEX_RB_NOTRECOV)) 1730 umtxq_signal(&key, 1); 1731 umtxq_unbusy(&key); 1732 umtxq_unlock(&key); 1733 umtx_key_release(&key); 1734 return (error); 1735 } 1736 1737 struct umtx_pi * 1738 umtx_pi_alloc(int flags) 1739 { 1740 struct umtx_pi *pi; 1741 1742 pi = uma_zalloc(umtx_pi_zone, M_ZERO | flags); 1743 TAILQ_INIT(&pi->pi_blocked); 1744 atomic_add_int(&umtx_pi_allocated, 1); 1745 return (pi); 1746 } 1747 1748 void 1749 umtx_pi_free(struct umtx_pi *pi) 1750 { 1751 uma_zfree(umtx_pi_zone, pi); 1752 atomic_add_int(&umtx_pi_allocated, -1); 1753 } 1754 1755 /* 1756 * Adjust the thread's position on a pi_state after its priority has been 1757 * changed. 1758 */ 1759 static int 1760 umtx_pi_adjust_thread(struct umtx_pi *pi, struct thread *td) 1761 { 1762 struct umtx_q *uq, *uq1, *uq2; 1763 struct thread *td1; 1764 1765 mtx_assert(&umtx_lock, MA_OWNED); 1766 if (pi == NULL) 1767 return (0); 1768 1769 uq = td->td_umtxq; 1770 1771 /* 1772 * Check if the thread needs to be moved on the blocked chain. 1773 * It needs to be moved if either its priority is lower than 1774 * the previous thread or higher than the next thread. 1775 */ 1776 uq1 = TAILQ_PREV(uq, umtxq_head, uq_lockq); 1777 uq2 = TAILQ_NEXT(uq, uq_lockq); 1778 if ((uq1 != NULL && UPRI(td) < UPRI(uq1->uq_thread)) || 1779 (uq2 != NULL && UPRI(td) > UPRI(uq2->uq_thread))) { 1780 /* 1781 * Remove thread from blocked chain and determine where 1782 * it should be moved to. 1783 */ 1784 TAILQ_REMOVE(&pi->pi_blocked, uq, uq_lockq); 1785 TAILQ_FOREACH(uq1, &pi->pi_blocked, uq_lockq) { 1786 td1 = uq1->uq_thread; 1787 MPASS(td1->td_proc->p_magic == P_MAGIC); 1788 if (UPRI(td1) > UPRI(td)) 1789 break; 1790 } 1791 1792 if (uq1 == NULL) 1793 TAILQ_INSERT_TAIL(&pi->pi_blocked, uq, uq_lockq); 1794 else 1795 TAILQ_INSERT_BEFORE(uq1, uq, uq_lockq); 1796 } 1797 return (1); 1798 } 1799 1800 static struct umtx_pi * 1801 umtx_pi_next(struct umtx_pi *pi) 1802 { 1803 struct umtx_q *uq_owner; 1804 1805 if (pi->pi_owner == NULL) 1806 return (NULL); 1807 uq_owner = pi->pi_owner->td_umtxq; 1808 if (uq_owner == NULL) 1809 return (NULL); 1810 return (uq_owner->uq_pi_blocked); 1811 } 1812 1813 /* 1814 * Floyd's Cycle-Finding Algorithm. 1815 */ 1816 static bool 1817 umtx_pi_check_loop(struct umtx_pi *pi) 1818 { 1819 struct umtx_pi *pi1; /* fast iterator */ 1820 1821 mtx_assert(&umtx_lock, MA_OWNED); 1822 if (pi == NULL) 1823 return (false); 1824 pi1 = pi; 1825 for (;;) { 1826 pi = umtx_pi_next(pi); 1827 if (pi == NULL) 1828 break; 1829 pi1 = umtx_pi_next(pi1); 1830 if (pi1 == NULL) 1831 break; 1832 pi1 = umtx_pi_next(pi1); 1833 if (pi1 == NULL) 1834 break; 1835 if (pi == pi1) 1836 return (true); 1837 } 1838 return (false); 1839 } 1840 1841 /* 1842 * Propagate priority when a thread is blocked on POSIX 1843 * PI mutex. 1844 */ 1845 static void 1846 umtx_propagate_priority(struct thread *td) 1847 { 1848 struct umtx_q *uq; 1849 struct umtx_pi *pi; 1850 int pri; 1851 1852 mtx_assert(&umtx_lock, MA_OWNED); 1853 pri = UPRI(td); 1854 uq = td->td_umtxq; 1855 pi = uq->uq_pi_blocked; 1856 if (pi == NULL) 1857 return; 1858 if (umtx_pi_check_loop(pi)) 1859 return; 1860 1861 for (;;) { 1862 td = pi->pi_owner; 1863 if (td == NULL || td == curthread) 1864 return; 1865 1866 MPASS(td->td_proc != NULL); 1867 MPASS(td->td_proc->p_magic == P_MAGIC); 1868 1869 thread_lock(td); 1870 if (td->td_lend_user_pri > pri) 1871 sched_lend_user_prio(td, pri); 1872 else { 1873 thread_unlock(td); 1874 break; 1875 } 1876 thread_unlock(td); 1877 1878 /* 1879 * Pick up the lock that td is blocked on. 1880 */ 1881 uq = td->td_umtxq; 1882 pi = uq->uq_pi_blocked; 1883 if (pi == NULL) 1884 break; 1885 /* Resort td on the list if needed. */ 1886 umtx_pi_adjust_thread(pi, td); 1887 } 1888 } 1889 1890 /* 1891 * Unpropagate priority for a PI mutex when a thread blocked on 1892 * it is interrupted by signal or resumed by others. 1893 */ 1894 static void 1895 umtx_repropagate_priority(struct umtx_pi *pi) 1896 { 1897 struct umtx_q *uq, *uq_owner; 1898 struct umtx_pi *pi2; 1899 int pri; 1900 1901 mtx_assert(&umtx_lock, MA_OWNED); 1902 1903 if (umtx_pi_check_loop(pi)) 1904 return; 1905 while (pi != NULL && pi->pi_owner != NULL) { 1906 pri = PRI_MAX; 1907 uq_owner = pi->pi_owner->td_umtxq; 1908 1909 TAILQ_FOREACH(pi2, &uq_owner->uq_pi_contested, pi_link) { 1910 uq = TAILQ_FIRST(&pi2->pi_blocked); 1911 if (uq != NULL) { 1912 if (pri > UPRI(uq->uq_thread)) 1913 pri = UPRI(uq->uq_thread); 1914 } 1915 } 1916 1917 if (pri > uq_owner->uq_inherited_pri) 1918 pri = uq_owner->uq_inherited_pri; 1919 thread_lock(pi->pi_owner); 1920 sched_lend_user_prio(pi->pi_owner, pri); 1921 thread_unlock(pi->pi_owner); 1922 if ((pi = uq_owner->uq_pi_blocked) != NULL) 1923 umtx_pi_adjust_thread(pi, uq_owner->uq_thread); 1924 } 1925 } 1926 1927 /* 1928 * Insert a PI mutex into owned list. 1929 */ 1930 static void 1931 umtx_pi_setowner(struct umtx_pi *pi, struct thread *owner) 1932 { 1933 struct umtx_q *uq_owner; 1934 1935 uq_owner = owner->td_umtxq; 1936 mtx_assert(&umtx_lock, MA_OWNED); 1937 MPASS(pi->pi_owner == NULL); 1938 pi->pi_owner = owner; 1939 TAILQ_INSERT_TAIL(&uq_owner->uq_pi_contested, pi, pi_link); 1940 } 1941 1942 /* 1943 * Disown a PI mutex, and remove it from the owned list. 1944 */ 1945 static void 1946 umtx_pi_disown(struct umtx_pi *pi) 1947 { 1948 1949 mtx_assert(&umtx_lock, MA_OWNED); 1950 TAILQ_REMOVE(&pi->pi_owner->td_umtxq->uq_pi_contested, pi, pi_link); 1951 pi->pi_owner = NULL; 1952 } 1953 1954 /* 1955 * Claim ownership of a PI mutex. 1956 */ 1957 int 1958 umtx_pi_claim(struct umtx_pi *pi, struct thread *owner) 1959 { 1960 struct umtx_q *uq; 1961 int pri; 1962 1963 mtx_lock(&umtx_lock); 1964 if (pi->pi_owner == owner) { 1965 mtx_unlock(&umtx_lock); 1966 return (0); 1967 } 1968 1969 if (pi->pi_owner != NULL) { 1970 /* 1971 * userland may have already messed the mutex, sigh. 1972 */ 1973 mtx_unlock(&umtx_lock); 1974 return (EPERM); 1975 } 1976 umtx_pi_setowner(pi, owner); 1977 uq = TAILQ_FIRST(&pi->pi_blocked); 1978 if (uq != NULL) { 1979 pri = UPRI(uq->uq_thread); 1980 thread_lock(owner); 1981 if (pri < UPRI(owner)) 1982 sched_lend_user_prio(owner, pri); 1983 thread_unlock(owner); 1984 } 1985 mtx_unlock(&umtx_lock); 1986 return (0); 1987 } 1988 1989 /* 1990 * Adjust a thread's order position in its blocked PI mutex, 1991 * this may result new priority propagating process. 1992 */ 1993 void 1994 umtx_pi_adjust(struct thread *td, u_char oldpri) 1995 { 1996 struct umtx_q *uq; 1997 struct umtx_pi *pi; 1998 1999 uq = td->td_umtxq; 2000 mtx_lock(&umtx_lock); 2001 /* 2002 * Pick up the lock that td is blocked on. 2003 */ 2004 pi = uq->uq_pi_blocked; 2005 if (pi != NULL) { 2006 umtx_pi_adjust_thread(pi, td); 2007 umtx_repropagate_priority(pi); 2008 } 2009 mtx_unlock(&umtx_lock); 2010 } 2011 2012 /* 2013 * Sleep on a PI mutex. 2014 */ 2015 int 2016 umtxq_sleep_pi(struct umtx_q *uq, struct umtx_pi *pi, uint32_t owner, 2017 const char *wmesg, struct umtx_abs_timeout *timo, bool shared) 2018 { 2019 struct thread *td, *td1; 2020 struct umtx_q *uq1; 2021 int error, pri; 2022 #ifdef INVARIANTS 2023 struct umtxq_chain *uc; 2024 2025 uc = umtxq_getchain(&pi->pi_key); 2026 #endif 2027 error = 0; 2028 td = uq->uq_thread; 2029 KASSERT(td == curthread, ("inconsistent uq_thread")); 2030 UMTXQ_LOCKED_ASSERT(umtxq_getchain(&uq->uq_key)); 2031 KASSERT(uc->uc_busy != 0, ("umtx chain is not busy")); 2032 umtxq_insert(uq); 2033 mtx_lock(&umtx_lock); 2034 if (pi->pi_owner == NULL) { 2035 mtx_unlock(&umtx_lock); 2036 td1 = tdfind(owner, shared ? -1 : td->td_proc->p_pid); 2037 mtx_lock(&umtx_lock); 2038 if (td1 != NULL) { 2039 if (pi->pi_owner == NULL) 2040 umtx_pi_setowner(pi, td1); 2041 PROC_UNLOCK(td1->td_proc); 2042 } 2043 } 2044 2045 TAILQ_FOREACH(uq1, &pi->pi_blocked, uq_lockq) { 2046 pri = UPRI(uq1->uq_thread); 2047 if (pri > UPRI(td)) 2048 break; 2049 } 2050 2051 if (uq1 != NULL) 2052 TAILQ_INSERT_BEFORE(uq1, uq, uq_lockq); 2053 else 2054 TAILQ_INSERT_TAIL(&pi->pi_blocked, uq, uq_lockq); 2055 2056 uq->uq_pi_blocked = pi; 2057 thread_lock(td); 2058 td->td_flags |= TDF_UPIBLOCKED; 2059 thread_unlock(td); 2060 umtx_propagate_priority(td); 2061 mtx_unlock(&umtx_lock); 2062 umtxq_unbusy(&uq->uq_key); 2063 2064 error = umtxq_sleep(uq, wmesg, timo); 2065 umtxq_remove(uq); 2066 2067 mtx_lock(&umtx_lock); 2068 uq->uq_pi_blocked = NULL; 2069 thread_lock(td); 2070 td->td_flags &= ~TDF_UPIBLOCKED; 2071 thread_unlock(td); 2072 TAILQ_REMOVE(&pi->pi_blocked, uq, uq_lockq); 2073 umtx_repropagate_priority(pi); 2074 mtx_unlock(&umtx_lock); 2075 umtxq_unlock(&uq->uq_key); 2076 2077 return (error); 2078 } 2079 2080 /* 2081 * Add reference count for a PI mutex. 2082 */ 2083 void 2084 umtx_pi_ref(struct umtx_pi *pi) 2085 { 2086 2087 UMTXQ_LOCKED_ASSERT(umtxq_getchain(&pi->pi_key)); 2088 pi->pi_refcount++; 2089 } 2090 2091 /* 2092 * Decrease reference count for a PI mutex, if the counter 2093 * is decreased to zero, its memory space is freed. 2094 */ 2095 void 2096 umtx_pi_unref(struct umtx_pi *pi) 2097 { 2098 struct umtxq_chain *uc; 2099 2100 uc = umtxq_getchain(&pi->pi_key); 2101 UMTXQ_LOCKED_ASSERT(uc); 2102 KASSERT(pi->pi_refcount > 0, ("invalid reference count")); 2103 if (--pi->pi_refcount == 0) { 2104 mtx_lock(&umtx_lock); 2105 if (pi->pi_owner != NULL) 2106 umtx_pi_disown(pi); 2107 KASSERT(TAILQ_EMPTY(&pi->pi_blocked), 2108 ("blocked queue not empty")); 2109 mtx_unlock(&umtx_lock); 2110 TAILQ_REMOVE(&uc->uc_pi_list, pi, pi_hashlink); 2111 umtx_pi_free(pi); 2112 } 2113 } 2114 2115 /* 2116 * Find a PI mutex in hash table. 2117 */ 2118 struct umtx_pi * 2119 umtx_pi_lookup(struct umtx_key *key) 2120 { 2121 struct umtxq_chain *uc; 2122 struct umtx_pi *pi; 2123 2124 uc = umtxq_getchain(key); 2125 UMTXQ_LOCKED_ASSERT(uc); 2126 2127 TAILQ_FOREACH(pi, &uc->uc_pi_list, pi_hashlink) { 2128 if (umtx_key_match(&pi->pi_key, key)) { 2129 return (pi); 2130 } 2131 } 2132 return (NULL); 2133 } 2134 2135 /* 2136 * Insert a PI mutex into hash table. 2137 */ 2138 void 2139 umtx_pi_insert(struct umtx_pi *pi) 2140 { 2141 struct umtxq_chain *uc; 2142 2143 uc = umtxq_getchain(&pi->pi_key); 2144 UMTXQ_LOCKED_ASSERT(uc); 2145 TAILQ_INSERT_TAIL(&uc->uc_pi_list, pi, pi_hashlink); 2146 } 2147 2148 /* 2149 * Drop a PI mutex and wakeup a top waiter. 2150 */ 2151 int 2152 umtx_pi_drop(struct thread *td, struct umtx_key *key, bool rb, int *count) 2153 { 2154 struct umtx_q *uq_first, *uq_first2, *uq_me; 2155 struct umtx_pi *pi, *pi2; 2156 int pri; 2157 2158 UMTXQ_ASSERT_LOCKED_BUSY(key); 2159 *count = umtxq_count_pi(key, &uq_first); 2160 if (uq_first != NULL) { 2161 mtx_lock(&umtx_lock); 2162 pi = uq_first->uq_pi_blocked; 2163 KASSERT(pi != NULL, ("pi == NULL?")); 2164 if (pi->pi_owner != td && !(rb && pi->pi_owner == NULL)) { 2165 mtx_unlock(&umtx_lock); 2166 /* userland messed the mutex */ 2167 return (EPERM); 2168 } 2169 uq_me = td->td_umtxq; 2170 if (pi->pi_owner == td) 2171 umtx_pi_disown(pi); 2172 /* get highest priority thread which is still sleeping. */ 2173 uq_first = TAILQ_FIRST(&pi->pi_blocked); 2174 while (uq_first != NULL && 2175 (uq_first->uq_flags & UQF_UMTXQ) == 0) { 2176 uq_first = TAILQ_NEXT(uq_first, uq_lockq); 2177 } 2178 pri = PRI_MAX; 2179 TAILQ_FOREACH(pi2, &uq_me->uq_pi_contested, pi_link) { 2180 uq_first2 = TAILQ_FIRST(&pi2->pi_blocked); 2181 if (uq_first2 != NULL) { 2182 if (pri > UPRI(uq_first2->uq_thread)) 2183 pri = UPRI(uq_first2->uq_thread); 2184 } 2185 } 2186 thread_lock(td); 2187 sched_lend_user_prio(td, pri); 2188 thread_unlock(td); 2189 mtx_unlock(&umtx_lock); 2190 if (uq_first) 2191 umtxq_signal_thread(uq_first); 2192 } else { 2193 pi = umtx_pi_lookup(key); 2194 /* 2195 * A umtx_pi can exist if a signal or timeout removed the 2196 * last waiter from the umtxq, but there is still 2197 * a thread in do_lock_pi() holding the umtx_pi. 2198 */ 2199 if (pi != NULL) { 2200 /* 2201 * The umtx_pi can be unowned, such as when a thread 2202 * has just entered do_lock_pi(), allocated the 2203 * umtx_pi, and unlocked the umtxq. 2204 * If the current thread owns it, it must disown it. 2205 */ 2206 mtx_lock(&umtx_lock); 2207 if (pi->pi_owner == td) 2208 umtx_pi_disown(pi); 2209 mtx_unlock(&umtx_lock); 2210 } 2211 } 2212 return (0); 2213 } 2214 2215 /* 2216 * Lock a PI mutex. 2217 */ 2218 static int 2219 do_lock_pi(struct thread *td, struct umutex *m, uint32_t flags, 2220 struct _umtx_time *timeout, int try) 2221 { 2222 struct umtx_abs_timeout timo; 2223 struct umtx_q *uq; 2224 struct umtx_pi *pi, *new_pi; 2225 uint32_t id, old_owner, owner, old; 2226 int error, rv; 2227 2228 id = td->td_tid; 2229 uq = td->td_umtxq; 2230 2231 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2232 TYPE_PI_ROBUST_UMUTEX : TYPE_PI_UMUTEX, GET_SHARE(flags), 2233 &uq->uq_key)) != 0) 2234 return (error); 2235 2236 if (timeout != NULL) 2237 umtx_abs_timeout_init2(&timo, timeout); 2238 2239 umtxq_lock(&uq->uq_key); 2240 pi = umtx_pi_lookup(&uq->uq_key); 2241 if (pi == NULL) { 2242 new_pi = umtx_pi_alloc(M_NOWAIT); 2243 if (new_pi == NULL) { 2244 umtxq_unlock(&uq->uq_key); 2245 new_pi = umtx_pi_alloc(M_WAITOK); 2246 umtxq_lock(&uq->uq_key); 2247 pi = umtx_pi_lookup(&uq->uq_key); 2248 if (pi != NULL) { 2249 umtx_pi_free(new_pi); 2250 new_pi = NULL; 2251 } 2252 } 2253 if (new_pi != NULL) { 2254 new_pi->pi_key = uq->uq_key; 2255 umtx_pi_insert(new_pi); 2256 pi = new_pi; 2257 } 2258 } 2259 umtx_pi_ref(pi); 2260 umtxq_unlock(&uq->uq_key); 2261 2262 /* 2263 * Care must be exercised when dealing with umtx structure. It 2264 * can fault on any access. 2265 */ 2266 for (;;) { 2267 /* 2268 * Try the uncontested case. This should be done in userland. 2269 */ 2270 rv = casueword32(&m->m_owner, UMUTEX_UNOWNED, &owner, id); 2271 /* The address was invalid. */ 2272 if (rv == -1) { 2273 error = EFAULT; 2274 break; 2275 } 2276 /* The acquire succeeded. */ 2277 if (rv == 0) { 2278 MPASS(owner == UMUTEX_UNOWNED); 2279 error = 0; 2280 break; 2281 } 2282 2283 if (owner == UMUTEX_RB_NOTRECOV) { 2284 error = ENOTRECOVERABLE; 2285 break; 2286 } 2287 2288 /* 2289 * Nobody owns it, but the acquire failed. This can happen 2290 * with ll/sc atomics. 2291 */ 2292 if (owner == UMUTEX_UNOWNED) { 2293 error = thread_check_susp(td, true); 2294 if (error != 0) 2295 break; 2296 continue; 2297 } 2298 2299 /* 2300 * Avoid overwriting a possible error from sleep due 2301 * to the pending signal with suspension check result. 2302 */ 2303 if (error == 0) { 2304 error = thread_check_susp(td, true); 2305 if (error != 0) 2306 break; 2307 } 2308 2309 /* If no one owns it but it is contested try to acquire it. */ 2310 if (owner == UMUTEX_CONTESTED || owner == UMUTEX_RB_OWNERDEAD) { 2311 old_owner = owner; 2312 rv = casueword32(&m->m_owner, owner, &owner, 2313 id | UMUTEX_CONTESTED); 2314 /* The address was invalid. */ 2315 if (rv == -1) { 2316 error = EFAULT; 2317 break; 2318 } 2319 if (rv == 1) { 2320 if (error == 0) { 2321 error = thread_check_susp(td, true); 2322 if (error != 0) 2323 break; 2324 } 2325 2326 /* 2327 * If this failed the lock could 2328 * changed, restart. 2329 */ 2330 continue; 2331 } 2332 2333 MPASS(rv == 0); 2334 MPASS(owner == old_owner); 2335 umtxq_lock(&uq->uq_key); 2336 umtxq_busy(&uq->uq_key); 2337 error = umtx_pi_claim(pi, td); 2338 umtxq_unbusy(&uq->uq_key); 2339 umtxq_unlock(&uq->uq_key); 2340 if (error != 0) { 2341 /* 2342 * Since we're going to return an 2343 * error, restore the m_owner to its 2344 * previous, unowned state to avoid 2345 * compounding the problem. 2346 */ 2347 (void)casuword32(&m->m_owner, 2348 id | UMUTEX_CONTESTED, old_owner); 2349 } 2350 if (error == 0 && old_owner == UMUTEX_RB_OWNERDEAD) 2351 error = EOWNERDEAD; 2352 break; 2353 } 2354 2355 if ((owner & ~UMUTEX_CONTESTED) == id) { 2356 error = EDEADLK; 2357 break; 2358 } 2359 2360 if (try != 0) { 2361 error = EBUSY; 2362 break; 2363 } 2364 2365 /* 2366 * If we caught a signal, we have retried and now 2367 * exit immediately. 2368 */ 2369 if (error != 0) 2370 break; 2371 2372 umtxq_lock(&uq->uq_key); 2373 umtxq_busy(&uq->uq_key); 2374 umtxq_unlock(&uq->uq_key); 2375 2376 /* 2377 * Set the contested bit so that a release in user space 2378 * knows to use the system call for unlock. If this fails 2379 * either some one else has acquired the lock or it has been 2380 * released. 2381 */ 2382 rv = casueword32(&m->m_owner, owner, &old, owner | 2383 UMUTEX_CONTESTED); 2384 2385 /* The address was invalid. */ 2386 if (rv == -1) { 2387 umtxq_unbusy_unlocked(&uq->uq_key); 2388 error = EFAULT; 2389 break; 2390 } 2391 if (rv == 1) { 2392 umtxq_unbusy_unlocked(&uq->uq_key); 2393 error = thread_check_susp(td, true); 2394 if (error != 0) 2395 break; 2396 2397 /* 2398 * The lock changed and we need to retry or we 2399 * lost a race to the thread unlocking the 2400 * umtx. Note that the UMUTEX_RB_OWNERDEAD 2401 * value for owner is impossible there. 2402 */ 2403 continue; 2404 } 2405 2406 umtxq_lock(&uq->uq_key); 2407 2408 /* We set the contested bit, sleep. */ 2409 MPASS(old == owner); 2410 error = umtxq_sleep_pi(uq, pi, owner & ~UMUTEX_CONTESTED, 2411 "umtxpi", timeout == NULL ? NULL : &timo, 2412 (flags & USYNC_PROCESS_SHARED) != 0); 2413 if (error != 0) 2414 continue; 2415 2416 error = thread_check_susp(td, false); 2417 if (error != 0) 2418 break; 2419 } 2420 2421 umtxq_lock(&uq->uq_key); 2422 umtx_pi_unref(pi); 2423 umtxq_unlock(&uq->uq_key); 2424 2425 umtx_key_release(&uq->uq_key); 2426 return (error); 2427 } 2428 2429 /* 2430 * Unlock a PI mutex. 2431 */ 2432 static int 2433 do_unlock_pi(struct thread *td, struct umutex *m, uint32_t flags, bool rb) 2434 { 2435 struct umtx_key key; 2436 uint32_t id, new_owner, old, owner; 2437 int count, error; 2438 2439 id = td->td_tid; 2440 2441 usrloop: 2442 /* 2443 * Make sure we own this mtx. 2444 */ 2445 error = fueword32(&m->m_owner, &owner); 2446 if (error == -1) 2447 return (EFAULT); 2448 2449 if ((owner & ~UMUTEX_CONTESTED) != id) 2450 return (EPERM); 2451 2452 new_owner = umtx_unlock_val(flags, rb); 2453 2454 /* This should be done in userland */ 2455 if ((owner & UMUTEX_CONTESTED) == 0) { 2456 error = casueword32(&m->m_owner, owner, &old, new_owner); 2457 if (error == -1) 2458 return (EFAULT); 2459 if (error == 1) { 2460 error = thread_check_susp(td, true); 2461 if (error != 0) 2462 return (error); 2463 goto usrloop; 2464 } 2465 if (old == owner) 2466 return (0); 2467 owner = old; 2468 } 2469 2470 /* We should only ever be in here for contested locks */ 2471 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2472 TYPE_PI_ROBUST_UMUTEX : TYPE_PI_UMUTEX, GET_SHARE(flags), 2473 &key)) != 0) 2474 return (error); 2475 2476 umtxq_lock(&key); 2477 umtxq_busy(&key); 2478 error = umtx_pi_drop(td, &key, rb, &count); 2479 if (error != 0) { 2480 umtxq_unbusy(&key); 2481 umtxq_unlock(&key); 2482 umtx_key_release(&key); 2483 /* userland messed the mutex */ 2484 return (error); 2485 } 2486 umtxq_unlock(&key); 2487 2488 /* 2489 * When unlocking the umtx, it must be marked as unowned if 2490 * there is zero or one thread only waiting for it. 2491 * Otherwise, it must be marked as contested. 2492 */ 2493 2494 if (count > 1) 2495 new_owner |= UMUTEX_CONTESTED; 2496 again: 2497 error = casueword32(&m->m_owner, owner, &old, new_owner); 2498 if (error == 1) { 2499 error = thread_check_susp(td, false); 2500 if (error == 0) 2501 goto again; 2502 } 2503 umtxq_unbusy_unlocked(&key); 2504 umtx_key_release(&key); 2505 if (error == -1) 2506 return (EFAULT); 2507 if (error == 0 && old != owner) 2508 return (EINVAL); 2509 return (error); 2510 } 2511 2512 /* 2513 * Lock a PP mutex. 2514 */ 2515 static int 2516 do_lock_pp(struct thread *td, struct umutex *m, uint32_t flags, 2517 struct _umtx_time *timeout, int try) 2518 { 2519 struct umtx_abs_timeout timo; 2520 struct umtx_q *uq, *uq2; 2521 struct umtx_pi *pi; 2522 uint32_t ceiling; 2523 uint32_t owner, id; 2524 int error, pri, old_inherited_pri, new_pri, rv; 2525 bool su; 2526 2527 id = td->td_tid; 2528 uq = td->td_umtxq; 2529 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2530 TYPE_PP_ROBUST_UMUTEX : TYPE_PP_UMUTEX, GET_SHARE(flags), 2531 &uq->uq_key)) != 0) 2532 return (error); 2533 2534 if (timeout != NULL) 2535 umtx_abs_timeout_init2(&timo, timeout); 2536 2537 su = (priv_check(td, PRIV_SCHED_RTPRIO) == 0); 2538 for (;;) { 2539 old_inherited_pri = uq->uq_inherited_pri; 2540 umtxq_lock(&uq->uq_key); 2541 umtxq_busy(&uq->uq_key); 2542 umtxq_unlock(&uq->uq_key); 2543 2544 rv = fueword32(&m->m_ceilings[0], &ceiling); 2545 if (rv == -1) { 2546 error = EFAULT; 2547 goto out; 2548 } 2549 ceiling = RTP_PRIO_MAX - ceiling; 2550 if (ceiling > RTP_PRIO_MAX) { 2551 error = EINVAL; 2552 goto out; 2553 } 2554 new_pri = PRI_MIN_REALTIME + ceiling; 2555 2556 if (td->td_base_user_pri < new_pri) { 2557 error = EINVAL; 2558 goto out; 2559 } 2560 if (su) { 2561 mtx_lock(&umtx_lock); 2562 if (new_pri < uq->uq_inherited_pri) { 2563 uq->uq_inherited_pri = new_pri; 2564 thread_lock(td); 2565 if (new_pri < UPRI(td)) 2566 sched_lend_user_prio(td, new_pri); 2567 thread_unlock(td); 2568 } 2569 mtx_unlock(&umtx_lock); 2570 } 2571 2572 rv = casueword32(&m->m_owner, UMUTEX_CONTESTED, &owner, 2573 id | UMUTEX_CONTESTED); 2574 /* The address was invalid. */ 2575 if (rv == -1) { 2576 error = EFAULT; 2577 break; 2578 } 2579 if (rv == 0) { 2580 MPASS(owner == UMUTEX_CONTESTED); 2581 error = 0; 2582 break; 2583 } 2584 /* rv == 1 */ 2585 if (owner == UMUTEX_RB_OWNERDEAD) { 2586 rv = casueword32(&m->m_owner, UMUTEX_RB_OWNERDEAD, 2587 &owner, id | UMUTEX_CONTESTED); 2588 if (rv == -1) { 2589 error = EFAULT; 2590 break; 2591 } 2592 if (rv == 0) { 2593 MPASS(owner == UMUTEX_RB_OWNERDEAD); 2594 error = EOWNERDEAD; /* success */ 2595 break; 2596 } 2597 2598 /* 2599 * rv == 1, only check for suspension if we 2600 * did not already catched a signal. If we 2601 * get an error from the check, the same 2602 * condition is checked by the umtxq_sleep() 2603 * call below, so we should obliterate the 2604 * error to not skip the last loop iteration. 2605 */ 2606 if (error == 0) { 2607 error = thread_check_susp(td, false); 2608 if (error == 0) { 2609 if (try != 0) 2610 error = EBUSY; 2611 else 2612 continue; 2613 } 2614 error = 0; 2615 } 2616 } else if (owner == UMUTEX_RB_NOTRECOV) { 2617 error = ENOTRECOVERABLE; 2618 } 2619 2620 if (try != 0) 2621 error = EBUSY; 2622 2623 /* 2624 * If we caught a signal, we have retried and now 2625 * exit immediately. 2626 */ 2627 if (error != 0) 2628 break; 2629 2630 umtxq_lock(&uq->uq_key); 2631 umtxq_insert(uq); 2632 umtxq_unbusy(&uq->uq_key); 2633 error = umtxq_sleep(uq, "umtxpp", timeout == NULL ? 2634 NULL : &timo); 2635 umtxq_remove(uq); 2636 umtxq_unlock(&uq->uq_key); 2637 2638 mtx_lock(&umtx_lock); 2639 uq->uq_inherited_pri = old_inherited_pri; 2640 pri = PRI_MAX; 2641 TAILQ_FOREACH(pi, &uq->uq_pi_contested, pi_link) { 2642 uq2 = TAILQ_FIRST(&pi->pi_blocked); 2643 if (uq2 != NULL) { 2644 if (pri > UPRI(uq2->uq_thread)) 2645 pri = UPRI(uq2->uq_thread); 2646 } 2647 } 2648 if (pri > uq->uq_inherited_pri) 2649 pri = uq->uq_inherited_pri; 2650 thread_lock(td); 2651 sched_lend_user_prio(td, pri); 2652 thread_unlock(td); 2653 mtx_unlock(&umtx_lock); 2654 } 2655 2656 if (error != 0 && error != EOWNERDEAD) { 2657 mtx_lock(&umtx_lock); 2658 uq->uq_inherited_pri = old_inherited_pri; 2659 pri = PRI_MAX; 2660 TAILQ_FOREACH(pi, &uq->uq_pi_contested, pi_link) { 2661 uq2 = TAILQ_FIRST(&pi->pi_blocked); 2662 if (uq2 != NULL) { 2663 if (pri > UPRI(uq2->uq_thread)) 2664 pri = UPRI(uq2->uq_thread); 2665 } 2666 } 2667 if (pri > uq->uq_inherited_pri) 2668 pri = uq->uq_inherited_pri; 2669 thread_lock(td); 2670 sched_lend_user_prio(td, pri); 2671 thread_unlock(td); 2672 mtx_unlock(&umtx_lock); 2673 } 2674 2675 out: 2676 umtxq_unbusy_unlocked(&uq->uq_key); 2677 umtx_key_release(&uq->uq_key); 2678 return (error); 2679 } 2680 2681 /* 2682 * Unlock a PP mutex. 2683 */ 2684 static int 2685 do_unlock_pp(struct thread *td, struct umutex *m, uint32_t flags, bool rb) 2686 { 2687 struct umtx_key key; 2688 struct umtx_q *uq, *uq2; 2689 struct umtx_pi *pi; 2690 uint32_t id, owner, rceiling; 2691 int error, pri, new_inherited_pri; 2692 bool su; 2693 2694 id = td->td_tid; 2695 uq = td->td_umtxq; 2696 su = (priv_check(td, PRIV_SCHED_RTPRIO) == 0); 2697 2698 /* 2699 * Make sure we own this mtx. 2700 */ 2701 error = fueword32(&m->m_owner, &owner); 2702 if (error == -1) 2703 return (EFAULT); 2704 2705 if ((owner & ~UMUTEX_CONTESTED) != id) 2706 return (EPERM); 2707 2708 error = copyin(&m->m_ceilings[1], &rceiling, sizeof(uint32_t)); 2709 if (error != 0) 2710 return (error); 2711 2712 if (rceiling == -1) 2713 new_inherited_pri = PRI_MAX; 2714 else { 2715 rceiling = RTP_PRIO_MAX - rceiling; 2716 if (rceiling > RTP_PRIO_MAX) 2717 return (EINVAL); 2718 new_inherited_pri = PRI_MIN_REALTIME + rceiling; 2719 } 2720 2721 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2722 TYPE_PP_ROBUST_UMUTEX : TYPE_PP_UMUTEX, GET_SHARE(flags), 2723 &key)) != 0) 2724 return (error); 2725 umtxq_lock(&key); 2726 umtxq_busy(&key); 2727 umtxq_unlock(&key); 2728 /* 2729 * For priority protected mutex, always set unlocked state 2730 * to UMUTEX_CONTESTED, so that userland always enters kernel 2731 * to lock the mutex, it is necessary because thread priority 2732 * has to be adjusted for such mutex. 2733 */ 2734 error = suword32(&m->m_owner, umtx_unlock_val(flags, rb) | 2735 UMUTEX_CONTESTED); 2736 2737 umtxq_lock(&key); 2738 if (error == 0) 2739 umtxq_signal(&key, 1); 2740 umtxq_unbusy(&key); 2741 umtxq_unlock(&key); 2742 2743 if (error == -1) 2744 error = EFAULT; 2745 else { 2746 mtx_lock(&umtx_lock); 2747 if (su || new_inherited_pri == PRI_MAX) 2748 uq->uq_inherited_pri = new_inherited_pri; 2749 pri = PRI_MAX; 2750 TAILQ_FOREACH(pi, &uq->uq_pi_contested, pi_link) { 2751 uq2 = TAILQ_FIRST(&pi->pi_blocked); 2752 if (uq2 != NULL) { 2753 if (pri > UPRI(uq2->uq_thread)) 2754 pri = UPRI(uq2->uq_thread); 2755 } 2756 } 2757 if (pri > uq->uq_inherited_pri) 2758 pri = uq->uq_inherited_pri; 2759 thread_lock(td); 2760 sched_lend_user_prio(td, pri); 2761 thread_unlock(td); 2762 mtx_unlock(&umtx_lock); 2763 } 2764 umtx_key_release(&key); 2765 return (error); 2766 } 2767 2768 static int 2769 do_set_ceiling(struct thread *td, struct umutex *m, uint32_t ceiling, 2770 uint32_t *old_ceiling) 2771 { 2772 struct umtx_q *uq; 2773 uint32_t flags, id, owner, save_ceiling; 2774 int error, rv, rv1; 2775 2776 error = fueword32(&m->m_flags, &flags); 2777 if (error == -1) 2778 return (EFAULT); 2779 if ((flags & UMUTEX_PRIO_PROTECT) == 0) 2780 return (EINVAL); 2781 if (ceiling > RTP_PRIO_MAX) 2782 return (EINVAL); 2783 id = td->td_tid; 2784 uq = td->td_umtxq; 2785 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2786 TYPE_PP_ROBUST_UMUTEX : TYPE_PP_UMUTEX, GET_SHARE(flags), 2787 &uq->uq_key)) != 0) 2788 return (error); 2789 for (;;) { 2790 umtxq_lock(&uq->uq_key); 2791 umtxq_busy(&uq->uq_key); 2792 umtxq_unlock(&uq->uq_key); 2793 2794 rv = fueword32(&m->m_ceilings[0], &save_ceiling); 2795 if (rv == -1) { 2796 error = EFAULT; 2797 break; 2798 } 2799 2800 rv = casueword32(&m->m_owner, UMUTEX_CONTESTED, &owner, 2801 id | UMUTEX_CONTESTED); 2802 if (rv == -1) { 2803 error = EFAULT; 2804 break; 2805 } 2806 2807 if (rv == 0) { 2808 MPASS(owner == UMUTEX_CONTESTED); 2809 rv = suword32(&m->m_ceilings[0], ceiling); 2810 rv1 = suword32(&m->m_owner, UMUTEX_CONTESTED); 2811 error = (rv == 0 && rv1 == 0) ? 0: EFAULT; 2812 break; 2813 } 2814 2815 if ((owner & ~UMUTEX_CONTESTED) == id) { 2816 rv = suword32(&m->m_ceilings[0], ceiling); 2817 error = rv == 0 ? 0 : EFAULT; 2818 break; 2819 } 2820 2821 if (owner == UMUTEX_RB_OWNERDEAD) { 2822 error = EOWNERDEAD; 2823 break; 2824 } else if (owner == UMUTEX_RB_NOTRECOV) { 2825 error = ENOTRECOVERABLE; 2826 break; 2827 } 2828 2829 /* 2830 * If we caught a signal, we have retried and now 2831 * exit immediately. 2832 */ 2833 if (error != 0) 2834 break; 2835 2836 /* 2837 * We set the contested bit, sleep. Otherwise the lock changed 2838 * and we need to retry or we lost a race to the thread 2839 * unlocking the umtx. 2840 */ 2841 umtxq_lock(&uq->uq_key); 2842 umtxq_insert(uq); 2843 umtxq_unbusy(&uq->uq_key); 2844 error = umtxq_sleep(uq, "umtxpp", NULL); 2845 umtxq_remove(uq); 2846 umtxq_unlock(&uq->uq_key); 2847 } 2848 umtxq_lock(&uq->uq_key); 2849 if (error == 0) 2850 umtxq_signal(&uq->uq_key, INT_MAX); 2851 umtxq_unbusy(&uq->uq_key); 2852 umtxq_unlock(&uq->uq_key); 2853 umtx_key_release(&uq->uq_key); 2854 if (error == 0 && old_ceiling != NULL) { 2855 rv = suword32(old_ceiling, save_ceiling); 2856 error = rv == 0 ? 0 : EFAULT; 2857 } 2858 return (error); 2859 } 2860 2861 /* 2862 * Lock a userland POSIX mutex. 2863 */ 2864 static int 2865 do_lock_umutex(struct thread *td, struct umutex *m, 2866 struct _umtx_time *timeout, int mode) 2867 { 2868 uint32_t flags; 2869 int error; 2870 2871 error = fueword32(&m->m_flags, &flags); 2872 if (error == -1) 2873 return (EFAULT); 2874 2875 switch (flags & (UMUTEX_PRIO_INHERIT | UMUTEX_PRIO_PROTECT)) { 2876 case 0: 2877 error = do_lock_normal(td, m, flags, timeout, mode); 2878 break; 2879 case UMUTEX_PRIO_INHERIT: 2880 error = do_lock_pi(td, m, flags, timeout, mode); 2881 break; 2882 case UMUTEX_PRIO_PROTECT: 2883 error = do_lock_pp(td, m, flags, timeout, mode); 2884 break; 2885 default: 2886 return (EINVAL); 2887 } 2888 if (timeout == NULL) { 2889 if (error == EINTR && mode != _UMUTEX_WAIT) 2890 error = ERESTART; 2891 } else { 2892 /* Timed-locking is not restarted. */ 2893 if (error == ERESTART) 2894 error = EINTR; 2895 } 2896 return (error); 2897 } 2898 2899 /* 2900 * Unlock a userland POSIX mutex. 2901 */ 2902 static int 2903 do_unlock_umutex(struct thread *td, struct umutex *m, bool rb) 2904 { 2905 uint32_t flags; 2906 int error; 2907 2908 error = fueword32(&m->m_flags, &flags); 2909 if (error == -1) 2910 return (EFAULT); 2911 2912 switch (flags & (UMUTEX_PRIO_INHERIT | UMUTEX_PRIO_PROTECT)) { 2913 case 0: 2914 return (do_unlock_normal(td, m, flags, rb)); 2915 case UMUTEX_PRIO_INHERIT: 2916 return (do_unlock_pi(td, m, flags, rb)); 2917 case UMUTEX_PRIO_PROTECT: 2918 return (do_unlock_pp(td, m, flags, rb)); 2919 } 2920 2921 return (EINVAL); 2922 } 2923 2924 static int 2925 do_cv_wait(struct thread *td, struct ucond *cv, struct umutex *m, 2926 struct timespec *timeout, u_long wflags) 2927 { 2928 struct umtx_abs_timeout timo; 2929 struct umtx_q *uq; 2930 uint32_t flags, clockid, hasw; 2931 int error; 2932 2933 uq = td->td_umtxq; 2934 error = fueword32(&cv->c_flags, &flags); 2935 if (error == -1) 2936 return (EFAULT); 2937 error = umtx_key_get(cv, TYPE_CV, GET_SHARE(flags), &uq->uq_key); 2938 if (error != 0) 2939 return (error); 2940 2941 if ((wflags & CVWAIT_CLOCKID) != 0) { 2942 error = fueword32(&cv->c_clockid, &clockid); 2943 if (error == -1) { 2944 umtx_key_release(&uq->uq_key); 2945 return (EFAULT); 2946 } 2947 if (clockid < CLOCK_REALTIME || 2948 clockid >= CLOCK_THREAD_CPUTIME_ID) { 2949 /* hmm, only HW clock id will work. */ 2950 umtx_key_release(&uq->uq_key); 2951 return (EINVAL); 2952 } 2953 } else { 2954 clockid = CLOCK_REALTIME; 2955 } 2956 2957 umtxq_lock(&uq->uq_key); 2958 umtxq_busy(&uq->uq_key); 2959 umtxq_insert(uq); 2960 umtxq_unlock(&uq->uq_key); 2961 2962 /* 2963 * Set c_has_waiters to 1 before releasing user mutex, also 2964 * don't modify cache line when unnecessary. 2965 */ 2966 error = fueword32(&cv->c_has_waiters, &hasw); 2967 if (error == 0 && hasw == 0) 2968 error = suword32(&cv->c_has_waiters, 1); 2969 if (error != 0) { 2970 umtxq_lock(&uq->uq_key); 2971 umtxq_remove(uq); 2972 umtxq_unbusy(&uq->uq_key); 2973 error = EFAULT; 2974 goto out; 2975 } 2976 2977 umtxq_unbusy_unlocked(&uq->uq_key); 2978 2979 error = do_unlock_umutex(td, m, false); 2980 2981 if (timeout != NULL) 2982 umtx_abs_timeout_init(&timo, clockid, 2983 (wflags & CVWAIT_ABSTIME) != 0, timeout); 2984 2985 umtxq_lock(&uq->uq_key); 2986 if (error == 0) { 2987 error = umtxq_sleep(uq, "ucond", timeout == NULL ? 2988 NULL : &timo); 2989 } 2990 2991 if ((uq->uq_flags & UQF_UMTXQ) == 0) 2992 error = 0; 2993 else { 2994 /* 2995 * This must be timeout,interrupted by signal or 2996 * surprious wakeup, clear c_has_waiter flag when 2997 * necessary. 2998 */ 2999 umtxq_busy(&uq->uq_key); 3000 if ((uq->uq_flags & UQF_UMTXQ) != 0) { 3001 int oldlen = uq->uq_cur_queue->length; 3002 umtxq_remove(uq); 3003 if (oldlen == 1) { 3004 umtxq_unlock(&uq->uq_key); 3005 if (suword32(&cv->c_has_waiters, 0) != 0 && 3006 error == 0) 3007 error = EFAULT; 3008 umtxq_lock(&uq->uq_key); 3009 } 3010 } 3011 umtxq_unbusy(&uq->uq_key); 3012 if (error == ERESTART) 3013 error = EINTR; 3014 } 3015 out: 3016 umtxq_unlock(&uq->uq_key); 3017 umtx_key_release(&uq->uq_key); 3018 return (error); 3019 } 3020 3021 /* 3022 * Signal a userland condition variable. 3023 */ 3024 static int 3025 do_cv_signal(struct thread *td, struct ucond *cv) 3026 { 3027 struct umtx_key key; 3028 int error, cnt, nwake; 3029 uint32_t flags; 3030 3031 error = fueword32(&cv->c_flags, &flags); 3032 if (error == -1) 3033 return (EFAULT); 3034 if ((error = umtx_key_get(cv, TYPE_CV, GET_SHARE(flags), &key)) != 0) 3035 return (error); 3036 umtxq_lock(&key); 3037 umtxq_busy(&key); 3038 cnt = umtxq_count(&key); 3039 nwake = umtxq_signal(&key, 1); 3040 if (cnt <= nwake) { 3041 umtxq_unlock(&key); 3042 error = suword32(&cv->c_has_waiters, 0); 3043 if (error == -1) 3044 error = EFAULT; 3045 umtxq_lock(&key); 3046 } 3047 umtxq_unbusy(&key); 3048 umtxq_unlock(&key); 3049 umtx_key_release(&key); 3050 return (error); 3051 } 3052 3053 static int 3054 do_cv_broadcast(struct thread *td, struct ucond *cv) 3055 { 3056 struct umtx_key key; 3057 int error; 3058 uint32_t flags; 3059 3060 error = fueword32(&cv->c_flags, &flags); 3061 if (error == -1) 3062 return (EFAULT); 3063 if ((error = umtx_key_get(cv, TYPE_CV, GET_SHARE(flags), &key)) != 0) 3064 return (error); 3065 3066 umtxq_lock(&key); 3067 umtxq_busy(&key); 3068 umtxq_signal(&key, INT_MAX); 3069 umtxq_unlock(&key); 3070 3071 error = suword32(&cv->c_has_waiters, 0); 3072 if (error == -1) 3073 error = EFAULT; 3074 3075 umtxq_unbusy_unlocked(&key); 3076 3077 umtx_key_release(&key); 3078 return (error); 3079 } 3080 3081 static int 3082 do_rw_rdlock(struct thread *td, struct urwlock *rwlock, long fflag, 3083 struct _umtx_time *timeout) 3084 { 3085 struct umtx_abs_timeout timo; 3086 struct umtx_q *uq; 3087 uint32_t flags, wrflags; 3088 int32_t state, oldstate; 3089 int32_t blocked_readers; 3090 int error, error1, rv; 3091 3092 uq = td->td_umtxq; 3093 error = fueword32(&rwlock->rw_flags, &flags); 3094 if (error == -1) 3095 return (EFAULT); 3096 error = umtx_key_get(rwlock, TYPE_RWLOCK, GET_SHARE(flags), &uq->uq_key); 3097 if (error != 0) 3098 return (error); 3099 3100 if (timeout != NULL) 3101 umtx_abs_timeout_init2(&timo, timeout); 3102 3103 wrflags = URWLOCK_WRITE_OWNER; 3104 if (!(fflag & URWLOCK_PREFER_READER) && !(flags & URWLOCK_PREFER_READER)) 3105 wrflags |= URWLOCK_WRITE_WAITERS; 3106 3107 for (;;) { 3108 rv = fueword32(&rwlock->rw_state, &state); 3109 if (rv == -1) { 3110 umtx_key_release(&uq->uq_key); 3111 return (EFAULT); 3112 } 3113 3114 /* try to lock it */ 3115 while (!(state & wrflags)) { 3116 if (__predict_false(URWLOCK_READER_COUNT(state) == 3117 URWLOCK_MAX_READERS)) { 3118 umtx_key_release(&uq->uq_key); 3119 return (EAGAIN); 3120 } 3121 rv = casueword32(&rwlock->rw_state, state, 3122 &oldstate, state + 1); 3123 if (rv == -1) { 3124 umtx_key_release(&uq->uq_key); 3125 return (EFAULT); 3126 } 3127 if (rv == 0) { 3128 MPASS(oldstate == state); 3129 umtx_key_release(&uq->uq_key); 3130 return (0); 3131 } 3132 error = thread_check_susp(td, true); 3133 if (error != 0) 3134 break; 3135 state = oldstate; 3136 } 3137 3138 if (error) 3139 break; 3140 3141 /* grab monitor lock */ 3142 umtxq_lock(&uq->uq_key); 3143 umtxq_busy(&uq->uq_key); 3144 umtxq_unlock(&uq->uq_key); 3145 3146 /* 3147 * re-read the state, in case it changed between the try-lock above 3148 * and the check below 3149 */ 3150 rv = fueword32(&rwlock->rw_state, &state); 3151 if (rv == -1) 3152 error = EFAULT; 3153 3154 /* set read contention bit */ 3155 while (error == 0 && (state & wrflags) && 3156 !(state & URWLOCK_READ_WAITERS)) { 3157 rv = casueword32(&rwlock->rw_state, state, 3158 &oldstate, state | URWLOCK_READ_WAITERS); 3159 if (rv == -1) { 3160 error = EFAULT; 3161 break; 3162 } 3163 if (rv == 0) { 3164 MPASS(oldstate == state); 3165 goto sleep; 3166 } 3167 state = oldstate; 3168 error = thread_check_susp(td, false); 3169 if (error != 0) 3170 break; 3171 } 3172 if (error != 0) { 3173 umtxq_unbusy_unlocked(&uq->uq_key); 3174 break; 3175 } 3176 3177 /* state is changed while setting flags, restart */ 3178 if (!(state & wrflags)) { 3179 umtxq_unbusy_unlocked(&uq->uq_key); 3180 error = thread_check_susp(td, true); 3181 if (error != 0) 3182 break; 3183 continue; 3184 } 3185 3186 sleep: 3187 /* 3188 * Contention bit is set, before sleeping, increase 3189 * read waiter count. 3190 */ 3191 rv = fueword32(&rwlock->rw_blocked_readers, 3192 &blocked_readers); 3193 if (rv == 0) 3194 rv = suword32(&rwlock->rw_blocked_readers, 3195 blocked_readers + 1); 3196 if (rv == -1) { 3197 umtxq_unbusy_unlocked(&uq->uq_key); 3198 error = EFAULT; 3199 break; 3200 } 3201 3202 while (state & wrflags) { 3203 umtxq_lock(&uq->uq_key); 3204 umtxq_insert(uq); 3205 umtxq_unbusy(&uq->uq_key); 3206 3207 error = umtxq_sleep(uq, "urdlck", timeout == NULL ? 3208 NULL : &timo); 3209 3210 umtxq_busy(&uq->uq_key); 3211 umtxq_remove(uq); 3212 umtxq_unlock(&uq->uq_key); 3213 if (error) 3214 break; 3215 rv = fueword32(&rwlock->rw_state, &state); 3216 if (rv == -1) { 3217 error = EFAULT; 3218 break; 3219 } 3220 } 3221 3222 /* decrease read waiter count, and may clear read contention bit */ 3223 rv = fueword32(&rwlock->rw_blocked_readers, 3224 &blocked_readers); 3225 if (rv == 0) 3226 rv = suword32(&rwlock->rw_blocked_readers, 3227 blocked_readers - 1); 3228 if (rv == -1) { 3229 umtxq_unbusy_unlocked(&uq->uq_key); 3230 error = EFAULT; 3231 break; 3232 } 3233 if (blocked_readers == 1) { 3234 rv = fueword32(&rwlock->rw_state, &state); 3235 if (rv == -1) { 3236 umtxq_unbusy_unlocked(&uq->uq_key); 3237 error = EFAULT; 3238 break; 3239 } 3240 for (;;) { 3241 rv = casueword32(&rwlock->rw_state, state, 3242 &oldstate, state & ~URWLOCK_READ_WAITERS); 3243 if (rv == -1) { 3244 error = EFAULT; 3245 break; 3246 } 3247 if (rv == 0) { 3248 MPASS(oldstate == state); 3249 break; 3250 } 3251 state = oldstate; 3252 error1 = thread_check_susp(td, false); 3253 if (error1 != 0) { 3254 if (error == 0) 3255 error = error1; 3256 break; 3257 } 3258 } 3259 } 3260 3261 umtxq_unbusy_unlocked(&uq->uq_key); 3262 if (error != 0) 3263 break; 3264 } 3265 umtx_key_release(&uq->uq_key); 3266 if (error == ERESTART) 3267 error = EINTR; 3268 return (error); 3269 } 3270 3271 static int 3272 do_rw_wrlock(struct thread *td, struct urwlock *rwlock, struct _umtx_time *timeout) 3273 { 3274 struct umtx_abs_timeout timo; 3275 struct umtx_q *uq; 3276 uint32_t flags; 3277 int32_t state, oldstate; 3278 int32_t blocked_writers; 3279 int32_t blocked_readers; 3280 int error, error1, rv; 3281 3282 uq = td->td_umtxq; 3283 error = fueword32(&rwlock->rw_flags, &flags); 3284 if (error == -1) 3285 return (EFAULT); 3286 error = umtx_key_get(rwlock, TYPE_RWLOCK, GET_SHARE(flags), &uq->uq_key); 3287 if (error != 0) 3288 return (error); 3289 3290 if (timeout != NULL) 3291 umtx_abs_timeout_init2(&timo, timeout); 3292 3293 blocked_readers = 0; 3294 for (;;) { 3295 rv = fueword32(&rwlock->rw_state, &state); 3296 if (rv == -1) { 3297 umtx_key_release(&uq->uq_key); 3298 return (EFAULT); 3299 } 3300 while ((state & URWLOCK_WRITE_OWNER) == 0 && 3301 URWLOCK_READER_COUNT(state) == 0) { 3302 rv = casueword32(&rwlock->rw_state, state, 3303 &oldstate, state | URWLOCK_WRITE_OWNER); 3304 if (rv == -1) { 3305 umtx_key_release(&uq->uq_key); 3306 return (EFAULT); 3307 } 3308 if (rv == 0) { 3309 MPASS(oldstate == state); 3310 umtx_key_release(&uq->uq_key); 3311 return (0); 3312 } 3313 state = oldstate; 3314 error = thread_check_susp(td, true); 3315 if (error != 0) 3316 break; 3317 } 3318 3319 if (error) { 3320 if ((state & (URWLOCK_WRITE_OWNER | 3321 URWLOCK_WRITE_WAITERS)) == 0 && 3322 blocked_readers != 0) { 3323 umtxq_lock(&uq->uq_key); 3324 umtxq_busy(&uq->uq_key); 3325 umtxq_signal_queue(&uq->uq_key, INT_MAX, 3326 UMTX_SHARED_QUEUE); 3327 umtxq_unbusy(&uq->uq_key); 3328 umtxq_unlock(&uq->uq_key); 3329 } 3330 3331 break; 3332 } 3333 3334 /* grab monitor lock */ 3335 umtxq_lock(&uq->uq_key); 3336 umtxq_busy(&uq->uq_key); 3337 umtxq_unlock(&uq->uq_key); 3338 3339 /* 3340 * Re-read the state, in case it changed between the 3341 * try-lock above and the check below. 3342 */ 3343 rv = fueword32(&rwlock->rw_state, &state); 3344 if (rv == -1) 3345 error = EFAULT; 3346 3347 while (error == 0 && ((state & URWLOCK_WRITE_OWNER) || 3348 URWLOCK_READER_COUNT(state) != 0) && 3349 (state & URWLOCK_WRITE_WAITERS) == 0) { 3350 rv = casueword32(&rwlock->rw_state, state, 3351 &oldstate, state | URWLOCK_WRITE_WAITERS); 3352 if (rv == -1) { 3353 error = EFAULT; 3354 break; 3355 } 3356 if (rv == 0) { 3357 MPASS(oldstate == state); 3358 goto sleep; 3359 } 3360 state = oldstate; 3361 error = thread_check_susp(td, false); 3362 if (error != 0) 3363 break; 3364 } 3365 if (error != 0) { 3366 umtxq_unbusy_unlocked(&uq->uq_key); 3367 break; 3368 } 3369 3370 if ((state & URWLOCK_WRITE_OWNER) == 0 && 3371 URWLOCK_READER_COUNT(state) == 0) { 3372 umtxq_unbusy_unlocked(&uq->uq_key); 3373 error = thread_check_susp(td, false); 3374 if (error != 0) 3375 break; 3376 continue; 3377 } 3378 sleep: 3379 rv = fueword32(&rwlock->rw_blocked_writers, 3380 &blocked_writers); 3381 if (rv == 0) 3382 rv = suword32(&rwlock->rw_blocked_writers, 3383 blocked_writers + 1); 3384 if (rv == -1) { 3385 umtxq_unbusy_unlocked(&uq->uq_key); 3386 error = EFAULT; 3387 break; 3388 } 3389 3390 while ((state & URWLOCK_WRITE_OWNER) || 3391 URWLOCK_READER_COUNT(state) != 0) { 3392 umtxq_lock(&uq->uq_key); 3393 umtxq_insert_queue(uq, UMTX_EXCLUSIVE_QUEUE); 3394 umtxq_unbusy(&uq->uq_key); 3395 3396 error = umtxq_sleep(uq, "uwrlck", timeout == NULL ? 3397 NULL : &timo); 3398 3399 umtxq_busy(&uq->uq_key); 3400 umtxq_remove_queue(uq, UMTX_EXCLUSIVE_QUEUE); 3401 umtxq_unlock(&uq->uq_key); 3402 if (error) 3403 break; 3404 rv = fueword32(&rwlock->rw_state, &state); 3405 if (rv == -1) { 3406 error = EFAULT; 3407 break; 3408 } 3409 } 3410 3411 rv = fueword32(&rwlock->rw_blocked_writers, 3412 &blocked_writers); 3413 if (rv == 0) 3414 rv = suword32(&rwlock->rw_blocked_writers, 3415 blocked_writers - 1); 3416 if (rv == -1) { 3417 umtxq_unbusy_unlocked(&uq->uq_key); 3418 error = EFAULT; 3419 break; 3420 } 3421 if (blocked_writers == 1) { 3422 rv = fueword32(&rwlock->rw_state, &state); 3423 if (rv == -1) { 3424 umtxq_unbusy_unlocked(&uq->uq_key); 3425 error = EFAULT; 3426 break; 3427 } 3428 for (;;) { 3429 rv = casueword32(&rwlock->rw_state, state, 3430 &oldstate, state & ~URWLOCK_WRITE_WAITERS); 3431 if (rv == -1) { 3432 error = EFAULT; 3433 break; 3434 } 3435 if (rv == 0) { 3436 MPASS(oldstate == state); 3437 break; 3438 } 3439 state = oldstate; 3440 error1 = thread_check_susp(td, false); 3441 /* 3442 * We are leaving the URWLOCK_WRITE_WAITERS 3443 * behind, but this should not harm the 3444 * correctness. 3445 */ 3446 if (error1 != 0) { 3447 if (error == 0) 3448 error = error1; 3449 break; 3450 } 3451 } 3452 rv = fueword32(&rwlock->rw_blocked_readers, 3453 &blocked_readers); 3454 if (rv == -1) { 3455 umtxq_unbusy_unlocked(&uq->uq_key); 3456 error = EFAULT; 3457 break; 3458 } 3459 } else 3460 blocked_readers = 0; 3461 3462 umtxq_unbusy_unlocked(&uq->uq_key); 3463 } 3464 3465 umtx_key_release(&uq->uq_key); 3466 if (error == ERESTART) 3467 error = EINTR; 3468 return (error); 3469 } 3470 3471 static int 3472 do_rw_unlock(struct thread *td, struct urwlock *rwlock) 3473 { 3474 struct umtx_q *uq; 3475 uint32_t flags; 3476 int32_t state, oldstate; 3477 int error, rv, q, count; 3478 3479 uq = td->td_umtxq; 3480 error = fueword32(&rwlock->rw_flags, &flags); 3481 if (error == -1) 3482 return (EFAULT); 3483 error = umtx_key_get(rwlock, TYPE_RWLOCK, GET_SHARE(flags), &uq->uq_key); 3484 if (error != 0) 3485 return (error); 3486 3487 error = fueword32(&rwlock->rw_state, &state); 3488 if (error == -1) { 3489 error = EFAULT; 3490 goto out; 3491 } 3492 if (state & URWLOCK_WRITE_OWNER) { 3493 for (;;) { 3494 rv = casueword32(&rwlock->rw_state, state, 3495 &oldstate, state & ~URWLOCK_WRITE_OWNER); 3496 if (rv == -1) { 3497 error = EFAULT; 3498 goto out; 3499 } 3500 if (rv == 1) { 3501 state = oldstate; 3502 if (!(oldstate & URWLOCK_WRITE_OWNER)) { 3503 error = EPERM; 3504 goto out; 3505 } 3506 error = thread_check_susp(td, true); 3507 if (error != 0) 3508 goto out; 3509 } else 3510 break; 3511 } 3512 } else if (URWLOCK_READER_COUNT(state) != 0) { 3513 for (;;) { 3514 rv = casueword32(&rwlock->rw_state, state, 3515 &oldstate, state - 1); 3516 if (rv == -1) { 3517 error = EFAULT; 3518 goto out; 3519 } 3520 if (rv == 1) { 3521 state = oldstate; 3522 if (URWLOCK_READER_COUNT(oldstate) == 0) { 3523 error = EPERM; 3524 goto out; 3525 } 3526 error = thread_check_susp(td, true); 3527 if (error != 0) 3528 goto out; 3529 } else 3530 break; 3531 } 3532 } else { 3533 error = EPERM; 3534 goto out; 3535 } 3536 3537 count = 0; 3538 3539 if (!(flags & URWLOCK_PREFER_READER)) { 3540 if (state & URWLOCK_WRITE_WAITERS) { 3541 count = 1; 3542 q = UMTX_EXCLUSIVE_QUEUE; 3543 } else if (state & URWLOCK_READ_WAITERS) { 3544 count = INT_MAX; 3545 q = UMTX_SHARED_QUEUE; 3546 } 3547 } else { 3548 if (state & URWLOCK_READ_WAITERS) { 3549 count = INT_MAX; 3550 q = UMTX_SHARED_QUEUE; 3551 } else if (state & URWLOCK_WRITE_WAITERS) { 3552 count = 1; 3553 q = UMTX_EXCLUSIVE_QUEUE; 3554 } 3555 } 3556 3557 if (count) { 3558 umtxq_lock(&uq->uq_key); 3559 umtxq_busy(&uq->uq_key); 3560 umtxq_signal_queue(&uq->uq_key, count, q); 3561 umtxq_unbusy(&uq->uq_key); 3562 umtxq_unlock(&uq->uq_key); 3563 } 3564 out: 3565 umtx_key_release(&uq->uq_key); 3566 return (error); 3567 } 3568 3569 #if defined(COMPAT_FREEBSD9) || defined(COMPAT_FREEBSD10) 3570 static int 3571 do_sem_wait(struct thread *td, struct _usem *sem, struct _umtx_time *timeout) 3572 { 3573 struct umtx_abs_timeout timo; 3574 struct umtx_q *uq; 3575 uint32_t flags, count, count1; 3576 int error, rv, rv1; 3577 3578 uq = td->td_umtxq; 3579 error = fueword32(&sem->_flags, &flags); 3580 if (error == -1) 3581 return (EFAULT); 3582 error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &uq->uq_key); 3583 if (error != 0) 3584 return (error); 3585 3586 if (timeout != NULL) 3587 umtx_abs_timeout_init2(&timo, timeout); 3588 3589 again: 3590 umtxq_lock(&uq->uq_key); 3591 umtxq_busy(&uq->uq_key); 3592 umtxq_insert(uq); 3593 umtxq_unlock(&uq->uq_key); 3594 rv = casueword32(&sem->_has_waiters, 0, &count1, 1); 3595 if (rv != -1) 3596 rv1 = fueword32(&sem->_count, &count); 3597 if (rv == -1 || rv1 == -1 || count != 0 || (rv == 1 && count1 == 0)) { 3598 if (rv == 0) 3599 rv = suword32(&sem->_has_waiters, 0); 3600 umtxq_lock(&uq->uq_key); 3601 umtxq_unbusy(&uq->uq_key); 3602 umtxq_remove(uq); 3603 umtxq_unlock(&uq->uq_key); 3604 if (rv == -1 || rv1 == -1) { 3605 error = EFAULT; 3606 goto out; 3607 } 3608 if (count != 0) { 3609 error = 0; 3610 goto out; 3611 } 3612 MPASS(rv == 1 && count1 == 0); 3613 rv = thread_check_susp(td, true); 3614 if (rv == 0) 3615 goto again; 3616 error = rv; 3617 goto out; 3618 } 3619 umtxq_lock(&uq->uq_key); 3620 umtxq_unbusy(&uq->uq_key); 3621 3622 error = umtxq_sleep(uq, "usem", timeout == NULL ? NULL : &timo); 3623 3624 if ((uq->uq_flags & UQF_UMTXQ) == 0) 3625 error = 0; 3626 else { 3627 umtxq_remove(uq); 3628 /* A relative timeout cannot be restarted. */ 3629 if (error == ERESTART && timeout != NULL && 3630 (timeout->_flags & UMTX_ABSTIME) == 0) 3631 error = EINTR; 3632 } 3633 umtxq_unlock(&uq->uq_key); 3634 out: 3635 umtx_key_release(&uq->uq_key); 3636 return (error); 3637 } 3638 3639 /* 3640 * Signal a userland semaphore. 3641 */ 3642 static int 3643 do_sem_wake(struct thread *td, struct _usem *sem) 3644 { 3645 struct umtx_key key; 3646 int error, cnt; 3647 uint32_t flags; 3648 3649 error = fueword32(&sem->_flags, &flags); 3650 if (error == -1) 3651 return (EFAULT); 3652 if ((error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &key)) != 0) 3653 return (error); 3654 umtxq_lock(&key); 3655 umtxq_busy(&key); 3656 cnt = umtxq_count(&key); 3657 if (cnt > 0) { 3658 /* 3659 * Check if count is greater than 0, this means the memory is 3660 * still being referenced by user code, so we can safely 3661 * update _has_waiters flag. 3662 */ 3663 if (cnt == 1) { 3664 umtxq_unlock(&key); 3665 error = suword32(&sem->_has_waiters, 0); 3666 umtxq_lock(&key); 3667 if (error == -1) 3668 error = EFAULT; 3669 } 3670 umtxq_signal(&key, 1); 3671 } 3672 umtxq_unbusy(&key); 3673 umtxq_unlock(&key); 3674 umtx_key_release(&key); 3675 return (error); 3676 } 3677 #endif 3678 3679 static int 3680 do_sem2_wait(struct thread *td, struct _usem2 *sem, struct _umtx_time *timeout) 3681 { 3682 struct umtx_abs_timeout timo; 3683 struct umtx_q *uq; 3684 uint32_t count, flags; 3685 int error, rv; 3686 3687 uq = td->td_umtxq; 3688 flags = fuword32(&sem->_flags); 3689 if (timeout != NULL) 3690 umtx_abs_timeout_init2(&timo, timeout); 3691 3692 again: 3693 error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &uq->uq_key); 3694 if (error != 0) 3695 return (error); 3696 umtxq_lock(&uq->uq_key); 3697 umtxq_busy(&uq->uq_key); 3698 umtxq_insert(uq); 3699 umtxq_unlock(&uq->uq_key); 3700 rv = fueword32(&sem->_count, &count); 3701 if (rv == -1) { 3702 umtxq_lock(&uq->uq_key); 3703 umtxq_unbusy(&uq->uq_key); 3704 umtxq_remove(uq); 3705 umtxq_unlock(&uq->uq_key); 3706 umtx_key_release(&uq->uq_key); 3707 return (EFAULT); 3708 } 3709 for (;;) { 3710 if (USEM_COUNT(count) != 0) { 3711 umtxq_lock(&uq->uq_key); 3712 umtxq_unbusy(&uq->uq_key); 3713 umtxq_remove(uq); 3714 umtxq_unlock(&uq->uq_key); 3715 umtx_key_release(&uq->uq_key); 3716 return (0); 3717 } 3718 if (count == USEM_HAS_WAITERS) 3719 break; 3720 rv = casueword32(&sem->_count, 0, &count, USEM_HAS_WAITERS); 3721 if (rv == 0) 3722 break; 3723 umtxq_lock(&uq->uq_key); 3724 umtxq_unbusy(&uq->uq_key); 3725 umtxq_remove(uq); 3726 umtxq_unlock(&uq->uq_key); 3727 umtx_key_release(&uq->uq_key); 3728 if (rv == -1) 3729 return (EFAULT); 3730 rv = thread_check_susp(td, true); 3731 if (rv != 0) 3732 return (rv); 3733 goto again; 3734 } 3735 umtxq_lock(&uq->uq_key); 3736 umtxq_unbusy(&uq->uq_key); 3737 3738 error = umtxq_sleep(uq, "usem", timeout == NULL ? NULL : &timo); 3739 3740 if ((uq->uq_flags & UQF_UMTXQ) == 0) 3741 error = 0; 3742 else { 3743 umtxq_remove(uq); 3744 if (timeout != NULL && (timeout->_flags & UMTX_ABSTIME) == 0) { 3745 /* A relative timeout cannot be restarted. */ 3746 if (error == ERESTART) 3747 error = EINTR; 3748 if (error == EINTR) { 3749 kern_clock_gettime(curthread, timo.clockid, 3750 &timo.cur); 3751 timespecsub(&timo.end, &timo.cur, 3752 &timeout->_timeout); 3753 } 3754 } 3755 } 3756 umtxq_unlock(&uq->uq_key); 3757 umtx_key_release(&uq->uq_key); 3758 return (error); 3759 } 3760 3761 /* 3762 * Signal a userland semaphore. 3763 */ 3764 static int 3765 do_sem2_wake(struct thread *td, struct _usem2 *sem) 3766 { 3767 struct umtx_key key; 3768 int error, cnt, rv; 3769 uint32_t count, flags; 3770 3771 rv = fueword32(&sem->_flags, &flags); 3772 if (rv == -1) 3773 return (EFAULT); 3774 if ((error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &key)) != 0) 3775 return (error); 3776 umtxq_lock(&key); 3777 umtxq_busy(&key); 3778 cnt = umtxq_count(&key); 3779 if (cnt > 0) { 3780 /* 3781 * If this was the last sleeping thread, clear the waiters 3782 * flag in _count. 3783 */ 3784 if (cnt == 1) { 3785 umtxq_unlock(&key); 3786 rv = fueword32(&sem->_count, &count); 3787 while (rv != -1 && count & USEM_HAS_WAITERS) { 3788 rv = casueword32(&sem->_count, count, &count, 3789 count & ~USEM_HAS_WAITERS); 3790 if (rv == 1) { 3791 rv = thread_check_susp(td, true); 3792 if (rv != 0) 3793 break; 3794 } 3795 } 3796 if (rv == -1) 3797 error = EFAULT; 3798 else if (rv > 0) { 3799 error = rv; 3800 } 3801 umtxq_lock(&key); 3802 } 3803 3804 umtxq_signal(&key, 1); 3805 } 3806 umtxq_unbusy(&key); 3807 umtxq_unlock(&key); 3808 umtx_key_release(&key); 3809 return (error); 3810 } 3811 3812 #ifdef COMPAT_FREEBSD10 3813 int 3814 freebsd10__umtx_lock(struct thread *td, struct freebsd10__umtx_lock_args *uap) 3815 { 3816 return (do_lock_umtx(td, uap->umtx, td->td_tid, 0)); 3817 } 3818 3819 int 3820 freebsd10__umtx_unlock(struct thread *td, 3821 struct freebsd10__umtx_unlock_args *uap) 3822 { 3823 return (do_unlock_umtx(td, uap->umtx, td->td_tid)); 3824 } 3825 #endif 3826 3827 inline int 3828 umtx_copyin_timeout(const void *uaddr, struct timespec *tsp) 3829 { 3830 int error; 3831 3832 error = copyin(uaddr, tsp, sizeof(*tsp)); 3833 if (error == 0) { 3834 if (!timespecvalid_interval(tsp)) 3835 error = EINVAL; 3836 } 3837 return (error); 3838 } 3839 3840 static inline int 3841 umtx_copyin_umtx_time(const void *uaddr, size_t size, struct _umtx_time *tp) 3842 { 3843 int error; 3844 3845 if (size <= sizeof(tp->_timeout)) { 3846 tp->_clockid = CLOCK_REALTIME; 3847 tp->_flags = 0; 3848 error = copyin(uaddr, &tp->_timeout, sizeof(tp->_timeout)); 3849 } else 3850 error = copyin(uaddr, tp, sizeof(*tp)); 3851 if (error != 0) 3852 return (error); 3853 if (!timespecvalid_interval(&tp->_timeout)) 3854 return (EINVAL); 3855 return (0); 3856 } 3857 3858 static int 3859 umtx_copyin_robust_lists(const void *uaddr, size_t size, 3860 struct umtx_robust_lists_params *rb) 3861 { 3862 3863 if (size > sizeof(*rb)) 3864 return (EINVAL); 3865 return (copyin(uaddr, rb, size)); 3866 } 3867 3868 static int 3869 umtx_copyout_timeout(void *uaddr, size_t sz, struct timespec *tsp) 3870 { 3871 3872 /* 3873 * Should be guaranteed by the caller, sz == uaddr1 - sizeof(_umtx_time) 3874 * and we're only called if sz >= sizeof(timespec) as supplied in the 3875 * copyops. 3876 */ 3877 KASSERT(sz >= sizeof(*tsp), 3878 ("umtx_copyops specifies incorrect sizes")); 3879 3880 return (copyout(tsp, uaddr, sizeof(*tsp))); 3881 } 3882 3883 #ifdef COMPAT_FREEBSD10 3884 static int 3885 __umtx_op_lock_umtx(struct thread *td, struct _umtx_op_args *uap, 3886 const struct umtx_copyops *ops) 3887 { 3888 struct timespec *ts, timeout; 3889 int error; 3890 3891 /* Allow a null timespec (wait forever). */ 3892 if (uap->uaddr2 == NULL) 3893 ts = NULL; 3894 else { 3895 error = ops->copyin_timeout(uap->uaddr2, &timeout); 3896 if (error != 0) 3897 return (error); 3898 ts = &timeout; 3899 } 3900 #ifdef COMPAT_FREEBSD32 3901 if (ops->compat32) 3902 return (do_lock_umtx32(td, uap->obj, uap->val, ts)); 3903 #endif 3904 return (do_lock_umtx(td, uap->obj, uap->val, ts)); 3905 } 3906 3907 static int 3908 __umtx_op_unlock_umtx(struct thread *td, struct _umtx_op_args *uap, 3909 const struct umtx_copyops *ops) 3910 { 3911 #ifdef COMPAT_FREEBSD32 3912 if (ops->compat32) 3913 return (do_unlock_umtx32(td, uap->obj, uap->val)); 3914 #endif 3915 return (do_unlock_umtx(td, uap->obj, uap->val)); 3916 } 3917 #endif /* COMPAT_FREEBSD10 */ 3918 3919 #if !defined(COMPAT_FREEBSD10) 3920 static int 3921 __umtx_op_unimpl(struct thread *td __unused, struct _umtx_op_args *uap __unused, 3922 const struct umtx_copyops *ops __unused) 3923 { 3924 return (EOPNOTSUPP); 3925 } 3926 #endif /* COMPAT_FREEBSD10 */ 3927 3928 static int 3929 __umtx_op_wait(struct thread *td, struct _umtx_op_args *uap, 3930 const struct umtx_copyops *ops) 3931 { 3932 struct _umtx_time timeout, *tm_p; 3933 int error; 3934 3935 if (uap->uaddr2 == NULL) 3936 tm_p = NULL; 3937 else { 3938 error = ops->copyin_umtx_time( 3939 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 3940 if (error != 0) 3941 return (error); 3942 tm_p = &timeout; 3943 } 3944 return (do_wait(td, uap->obj, uap->val, tm_p, ops->compat32, 0)); 3945 } 3946 3947 static int 3948 __umtx_op_wait_uint(struct thread *td, struct _umtx_op_args *uap, 3949 const struct umtx_copyops *ops) 3950 { 3951 struct _umtx_time timeout, *tm_p; 3952 int error; 3953 3954 if (uap->uaddr2 == NULL) 3955 tm_p = NULL; 3956 else { 3957 error = ops->copyin_umtx_time( 3958 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 3959 if (error != 0) 3960 return (error); 3961 tm_p = &timeout; 3962 } 3963 return (do_wait(td, uap->obj, uap->val, tm_p, 1, 0)); 3964 } 3965 3966 static int 3967 __umtx_op_wait_uint_private(struct thread *td, struct _umtx_op_args *uap, 3968 const struct umtx_copyops *ops) 3969 { 3970 struct _umtx_time *tm_p, timeout; 3971 int error; 3972 3973 if (uap->uaddr2 == NULL) 3974 tm_p = NULL; 3975 else { 3976 error = ops->copyin_umtx_time( 3977 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 3978 if (error != 0) 3979 return (error); 3980 tm_p = &timeout; 3981 } 3982 return (do_wait(td, uap->obj, uap->val, tm_p, 1, 1)); 3983 } 3984 3985 static int 3986 __umtx_op_wake(struct thread *td, struct _umtx_op_args *uap, 3987 const struct umtx_copyops *ops __unused) 3988 { 3989 3990 return (kern_umtx_wake(td, uap->obj, uap->val, 0)); 3991 } 3992 3993 #define BATCH_SIZE 128 3994 static int 3995 __umtx_op_nwake_private_native(struct thread *td, struct _umtx_op_args *uap) 3996 { 3997 char *uaddrs[BATCH_SIZE], **upp; 3998 int count, error, i, pos, tocopy; 3999 4000 upp = (char **)uap->obj; 4001 error = 0; 4002 for (count = uap->val, pos = 0; count > 0; count -= tocopy, 4003 pos += tocopy) { 4004 tocopy = MIN(count, BATCH_SIZE); 4005 error = copyin(upp + pos, uaddrs, tocopy * sizeof(char *)); 4006 if (error != 0) 4007 break; 4008 for (i = 0; i < tocopy; ++i) { 4009 kern_umtx_wake(td, uaddrs[i], INT_MAX, 1); 4010 } 4011 maybe_yield(); 4012 } 4013 return (error); 4014 } 4015 4016 static int 4017 __umtx_op_nwake_private_compat32(struct thread *td, struct _umtx_op_args *uap) 4018 { 4019 uint32_t uaddrs[BATCH_SIZE], *upp; 4020 int count, error, i, pos, tocopy; 4021 4022 upp = (uint32_t *)uap->obj; 4023 error = 0; 4024 for (count = uap->val, pos = 0; count > 0; count -= tocopy, 4025 pos += tocopy) { 4026 tocopy = MIN(count, BATCH_SIZE); 4027 error = copyin(upp + pos, uaddrs, tocopy * sizeof(uint32_t)); 4028 if (error != 0) 4029 break; 4030 for (i = 0; i < tocopy; ++i) { 4031 kern_umtx_wake(td, (void *)(uintptr_t)uaddrs[i], 4032 INT_MAX, 1); 4033 } 4034 maybe_yield(); 4035 } 4036 return (error); 4037 } 4038 4039 static int 4040 __umtx_op_nwake_private(struct thread *td, struct _umtx_op_args *uap, 4041 const struct umtx_copyops *ops) 4042 { 4043 4044 if (ops->compat32) 4045 return (__umtx_op_nwake_private_compat32(td, uap)); 4046 return (__umtx_op_nwake_private_native(td, uap)); 4047 } 4048 4049 static int 4050 __umtx_op_wake_private(struct thread *td, struct _umtx_op_args *uap, 4051 const struct umtx_copyops *ops __unused) 4052 { 4053 4054 return (kern_umtx_wake(td, uap->obj, uap->val, 1)); 4055 } 4056 4057 static int 4058 __umtx_op_lock_umutex(struct thread *td, struct _umtx_op_args *uap, 4059 const struct umtx_copyops *ops) 4060 { 4061 struct _umtx_time *tm_p, timeout; 4062 int error; 4063 4064 /* Allow a null timespec (wait forever). */ 4065 if (uap->uaddr2 == NULL) 4066 tm_p = NULL; 4067 else { 4068 error = ops->copyin_umtx_time( 4069 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 4070 if (error != 0) 4071 return (error); 4072 tm_p = &timeout; 4073 } 4074 return (do_lock_umutex(td, uap->obj, tm_p, 0)); 4075 } 4076 4077 static int 4078 __umtx_op_trylock_umutex(struct thread *td, struct _umtx_op_args *uap, 4079 const struct umtx_copyops *ops __unused) 4080 { 4081 4082 return (do_lock_umutex(td, uap->obj, NULL, _UMUTEX_TRY)); 4083 } 4084 4085 static int 4086 __umtx_op_wait_umutex(struct thread *td, struct _umtx_op_args *uap, 4087 const struct umtx_copyops *ops) 4088 { 4089 struct _umtx_time *tm_p, timeout; 4090 int error; 4091 4092 /* Allow a null timespec (wait forever). */ 4093 if (uap->uaddr2 == NULL) 4094 tm_p = NULL; 4095 else { 4096 error = ops->copyin_umtx_time( 4097 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 4098 if (error != 0) 4099 return (error); 4100 tm_p = &timeout; 4101 } 4102 return (do_lock_umutex(td, uap->obj, tm_p, _UMUTEX_WAIT)); 4103 } 4104 4105 static int 4106 __umtx_op_wake_umutex(struct thread *td, struct _umtx_op_args *uap, 4107 const struct umtx_copyops *ops __unused) 4108 { 4109 4110 return (do_wake_umutex(td, uap->obj)); 4111 } 4112 4113 static int 4114 __umtx_op_unlock_umutex(struct thread *td, struct _umtx_op_args *uap, 4115 const struct umtx_copyops *ops __unused) 4116 { 4117 4118 return (do_unlock_umutex(td, uap->obj, false)); 4119 } 4120 4121 static int 4122 __umtx_op_set_ceiling(struct thread *td, struct _umtx_op_args *uap, 4123 const struct umtx_copyops *ops __unused) 4124 { 4125 4126 return (do_set_ceiling(td, uap->obj, uap->val, uap->uaddr1)); 4127 } 4128 4129 static int 4130 __umtx_op_cv_wait(struct thread *td, struct _umtx_op_args *uap, 4131 const struct umtx_copyops *ops) 4132 { 4133 struct timespec *ts, timeout; 4134 int error; 4135 4136 /* Allow a null timespec (wait forever). */ 4137 if (uap->uaddr2 == NULL) 4138 ts = NULL; 4139 else { 4140 error = ops->copyin_timeout(uap->uaddr2, &timeout); 4141 if (error != 0) 4142 return (error); 4143 ts = &timeout; 4144 } 4145 return (do_cv_wait(td, uap->obj, uap->uaddr1, ts, uap->val)); 4146 } 4147 4148 static int 4149 __umtx_op_cv_signal(struct thread *td, struct _umtx_op_args *uap, 4150 const struct umtx_copyops *ops __unused) 4151 { 4152 4153 return (do_cv_signal(td, uap->obj)); 4154 } 4155 4156 static int 4157 __umtx_op_cv_broadcast(struct thread *td, struct _umtx_op_args *uap, 4158 const struct umtx_copyops *ops __unused) 4159 { 4160 4161 return (do_cv_broadcast(td, uap->obj)); 4162 } 4163 4164 static int 4165 __umtx_op_rw_rdlock(struct thread *td, struct _umtx_op_args *uap, 4166 const struct umtx_copyops *ops) 4167 { 4168 struct _umtx_time timeout; 4169 int error; 4170 4171 /* Allow a null timespec (wait forever). */ 4172 if (uap->uaddr2 == NULL) { 4173 error = do_rw_rdlock(td, uap->obj, uap->val, 0); 4174 } else { 4175 error = ops->copyin_umtx_time(uap->uaddr2, 4176 (size_t)uap->uaddr1, &timeout); 4177 if (error != 0) 4178 return (error); 4179 error = do_rw_rdlock(td, uap->obj, uap->val, &timeout); 4180 } 4181 return (error); 4182 } 4183 4184 static int 4185 __umtx_op_rw_wrlock(struct thread *td, struct _umtx_op_args *uap, 4186 const struct umtx_copyops *ops) 4187 { 4188 struct _umtx_time timeout; 4189 int error; 4190 4191 /* Allow a null timespec (wait forever). */ 4192 if (uap->uaddr2 == NULL) { 4193 error = do_rw_wrlock(td, uap->obj, 0); 4194 } else { 4195 error = ops->copyin_umtx_time(uap->uaddr2, 4196 (size_t)uap->uaddr1, &timeout); 4197 if (error != 0) 4198 return (error); 4199 4200 error = do_rw_wrlock(td, uap->obj, &timeout); 4201 } 4202 return (error); 4203 } 4204 4205 static int 4206 __umtx_op_rw_unlock(struct thread *td, struct _umtx_op_args *uap, 4207 const struct umtx_copyops *ops __unused) 4208 { 4209 4210 return (do_rw_unlock(td, uap->obj)); 4211 } 4212 4213 #if defined(COMPAT_FREEBSD9) || defined(COMPAT_FREEBSD10) 4214 static int 4215 __umtx_op_sem_wait(struct thread *td, struct _umtx_op_args *uap, 4216 const struct umtx_copyops *ops) 4217 { 4218 struct _umtx_time *tm_p, timeout; 4219 int error; 4220 4221 /* Allow a null timespec (wait forever). */ 4222 if (uap->uaddr2 == NULL) 4223 tm_p = NULL; 4224 else { 4225 error = ops->copyin_umtx_time( 4226 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 4227 if (error != 0) 4228 return (error); 4229 tm_p = &timeout; 4230 } 4231 return (do_sem_wait(td, uap->obj, tm_p)); 4232 } 4233 4234 static int 4235 __umtx_op_sem_wake(struct thread *td, struct _umtx_op_args *uap, 4236 const struct umtx_copyops *ops __unused) 4237 { 4238 4239 return (do_sem_wake(td, uap->obj)); 4240 } 4241 #endif 4242 4243 static int 4244 __umtx_op_wake2_umutex(struct thread *td, struct _umtx_op_args *uap, 4245 const struct umtx_copyops *ops __unused) 4246 { 4247 4248 return (do_wake2_umutex(td, uap->obj, uap->val)); 4249 } 4250 4251 static int 4252 __umtx_op_sem2_wait(struct thread *td, struct _umtx_op_args *uap, 4253 const struct umtx_copyops *ops) 4254 { 4255 struct _umtx_time *tm_p, timeout; 4256 size_t uasize; 4257 int error; 4258 4259 /* Allow a null timespec (wait forever). */ 4260 if (uap->uaddr2 == NULL) { 4261 uasize = 0; 4262 tm_p = NULL; 4263 } else { 4264 uasize = (size_t)uap->uaddr1; 4265 error = ops->copyin_umtx_time(uap->uaddr2, uasize, &timeout); 4266 if (error != 0) 4267 return (error); 4268 tm_p = &timeout; 4269 } 4270 error = do_sem2_wait(td, uap->obj, tm_p); 4271 if (error == EINTR && uap->uaddr2 != NULL && 4272 (timeout._flags & UMTX_ABSTIME) == 0 && 4273 uasize >= ops->umtx_time_sz + ops->timespec_sz) { 4274 error = ops->copyout_timeout( 4275 (void *)((uintptr_t)uap->uaddr2 + ops->umtx_time_sz), 4276 uasize - ops->umtx_time_sz, &timeout._timeout); 4277 if (error == 0) { 4278 error = EINTR; 4279 } 4280 } 4281 4282 return (error); 4283 } 4284 4285 static int 4286 __umtx_op_sem2_wake(struct thread *td, struct _umtx_op_args *uap, 4287 const struct umtx_copyops *ops __unused) 4288 { 4289 4290 return (do_sem2_wake(td, uap->obj)); 4291 } 4292 4293 #define USHM_OBJ_UMTX(o) \ 4294 ((struct umtx_shm_obj_list *)(&(o)->umtx_data)) 4295 4296 #define USHMF_LINKED 0x0001 4297 struct umtx_shm_reg { 4298 TAILQ_ENTRY(umtx_shm_reg) ushm_reg_link; 4299 LIST_ENTRY(umtx_shm_reg) ushm_obj_link; 4300 struct umtx_key ushm_key; 4301 struct ucred *ushm_cred; 4302 struct shmfd *ushm_obj; 4303 u_int ushm_refcnt; 4304 u_int ushm_flags; 4305 }; 4306 4307 LIST_HEAD(umtx_shm_obj_list, umtx_shm_reg); 4308 TAILQ_HEAD(umtx_shm_reg_head, umtx_shm_reg); 4309 4310 static uma_zone_t umtx_shm_reg_zone; 4311 static struct umtx_shm_reg_head umtx_shm_registry[UMTX_CHAINS]; 4312 static struct mtx umtx_shm_lock; 4313 static struct umtx_shm_reg_head umtx_shm_reg_delfree = 4314 TAILQ_HEAD_INITIALIZER(umtx_shm_reg_delfree); 4315 4316 static void umtx_shm_free_reg(struct umtx_shm_reg *reg); 4317 4318 static void 4319 umtx_shm_reg_delfree_tq(void *context __unused, int pending __unused) 4320 { 4321 struct umtx_shm_reg_head d; 4322 struct umtx_shm_reg *reg, *reg1; 4323 4324 TAILQ_INIT(&d); 4325 mtx_lock(&umtx_shm_lock); 4326 TAILQ_CONCAT(&d, &umtx_shm_reg_delfree, ushm_reg_link); 4327 mtx_unlock(&umtx_shm_lock); 4328 TAILQ_FOREACH_SAFE(reg, &d, ushm_reg_link, reg1) { 4329 TAILQ_REMOVE(&d, reg, ushm_reg_link); 4330 umtx_shm_free_reg(reg); 4331 } 4332 } 4333 4334 static struct task umtx_shm_reg_delfree_task = 4335 TASK_INITIALIZER(0, umtx_shm_reg_delfree_tq, NULL); 4336 4337 /* 4338 * Returns 0 if a SHM with the passed key is found in the registry, in which 4339 * case it is returned through 'oreg'. Otherwise, returns an error among ESRCH 4340 * (no corresponding SHM; ESRCH was chosen for compatibility, ENOENT would have 4341 * been preferable) or EOVERFLOW (there is a corresponding SHM, but reference 4342 * count would overflow, so can't return it), in which case '*oreg' is left 4343 * unchanged. 4344 */ 4345 static int 4346 umtx_shm_find_reg_locked(const struct umtx_key *key, 4347 struct umtx_shm_reg **const oreg) 4348 { 4349 struct umtx_shm_reg *reg; 4350 struct umtx_shm_reg_head *reg_head; 4351 4352 KASSERT(key->shared, ("umtx_p_find_rg: private key")); 4353 mtx_assert(&umtx_shm_lock, MA_OWNED); 4354 reg_head = &umtx_shm_registry[key->hash]; 4355 TAILQ_FOREACH(reg, reg_head, ushm_reg_link) { 4356 KASSERT(reg->ushm_key.shared, 4357 ("non-shared key on reg %p %d", reg, reg->ushm_key.shared)); 4358 if (reg->ushm_key.info.shared.object == 4359 key->info.shared.object && 4360 reg->ushm_key.info.shared.offset == 4361 key->info.shared.offset) { 4362 KASSERT(reg->ushm_key.type == TYPE_SHM, ("TYPE_USHM")); 4363 KASSERT(reg->ushm_refcnt != 0, 4364 ("reg %p refcnt 0 onlist", reg)); 4365 KASSERT((reg->ushm_flags & USHMF_LINKED) != 0, 4366 ("reg %p not linked", reg)); 4367 /* 4368 * Don't let overflow happen, just deny a new reference 4369 * (this is additional protection against some reference 4370 * count leak, which is known not to be the case at the 4371 * time of this writing). 4372 */ 4373 if (__predict_false(reg->ushm_refcnt == UINT_MAX)) 4374 return (EOVERFLOW); 4375 reg->ushm_refcnt++; 4376 *oreg = reg; 4377 return (0); 4378 } 4379 } 4380 return (ESRCH); 4381 } 4382 4383 /* 4384 * Calls umtx_shm_find_reg_unlocked() under the 'umtx_shm_lock'. 4385 */ 4386 static int 4387 umtx_shm_find_reg(const struct umtx_key *key, struct umtx_shm_reg **const oreg) 4388 { 4389 int error; 4390 4391 mtx_lock(&umtx_shm_lock); 4392 error = umtx_shm_find_reg_locked(key, oreg); 4393 mtx_unlock(&umtx_shm_lock); 4394 return (error); 4395 } 4396 4397 static void 4398 umtx_shm_free_reg(struct umtx_shm_reg *reg) 4399 { 4400 4401 chgumtxcnt(reg->ushm_cred->cr_ruidinfo, -1, 0); 4402 crfree(reg->ushm_cred); 4403 shm_drop(reg->ushm_obj); 4404 uma_zfree(umtx_shm_reg_zone, reg); 4405 } 4406 4407 static bool 4408 umtx_shm_unref_reg_locked(struct umtx_shm_reg *reg, bool linked_ref) 4409 { 4410 mtx_assert(&umtx_shm_lock, MA_OWNED); 4411 KASSERT(reg->ushm_refcnt != 0, ("ushm_reg %p refcnt 0", reg)); 4412 4413 if (linked_ref) { 4414 if ((reg->ushm_flags & USHMF_LINKED) == 0) 4415 /* 4416 * The reference tied to USHMF_LINKED has already been 4417 * released concurrently. 4418 */ 4419 return (false); 4420 4421 TAILQ_REMOVE(&umtx_shm_registry[reg->ushm_key.hash], reg, 4422 ushm_reg_link); 4423 LIST_REMOVE(reg, ushm_obj_link); 4424 reg->ushm_flags &= ~USHMF_LINKED; 4425 } 4426 4427 reg->ushm_refcnt--; 4428 return (reg->ushm_refcnt == 0); 4429 } 4430 4431 static void 4432 umtx_shm_unref_reg(struct umtx_shm_reg *reg, bool linked_ref) 4433 { 4434 vm_object_t object; 4435 bool dofree; 4436 4437 if (linked_ref) { 4438 /* 4439 * Note: This may be executed multiple times on the same 4440 * shared-memory VM object in presence of concurrent callers 4441 * because 'umtx_shm_lock' is not held all along in umtx_shm() 4442 * and here. 4443 */ 4444 object = reg->ushm_obj->shm_object; 4445 VM_OBJECT_WLOCK(object); 4446 vm_object_set_flag(object, OBJ_UMTXDEAD); 4447 VM_OBJECT_WUNLOCK(object); 4448 } 4449 mtx_lock(&umtx_shm_lock); 4450 dofree = umtx_shm_unref_reg_locked(reg, linked_ref); 4451 mtx_unlock(&umtx_shm_lock); 4452 if (dofree) 4453 umtx_shm_free_reg(reg); 4454 } 4455 4456 void 4457 umtx_shm_object_init(vm_object_t object) 4458 { 4459 4460 LIST_INIT(USHM_OBJ_UMTX(object)); 4461 } 4462 4463 void 4464 umtx_shm_object_terminated(vm_object_t object) 4465 { 4466 struct umtx_shm_reg *reg, *reg1; 4467 bool dofree; 4468 4469 if (LIST_EMPTY(USHM_OBJ_UMTX(object))) 4470 return; 4471 4472 dofree = false; 4473 mtx_lock(&umtx_shm_lock); 4474 LIST_FOREACH_SAFE(reg, USHM_OBJ_UMTX(object), ushm_obj_link, reg1) { 4475 if (umtx_shm_unref_reg_locked(reg, true)) { 4476 TAILQ_INSERT_TAIL(&umtx_shm_reg_delfree, reg, 4477 ushm_reg_link); 4478 dofree = true; 4479 } 4480 } 4481 mtx_unlock(&umtx_shm_lock); 4482 if (dofree) 4483 taskqueue_enqueue(taskqueue_thread, &umtx_shm_reg_delfree_task); 4484 } 4485 4486 static int 4487 umtx_shm_create_reg(struct thread *td, const struct umtx_key *key, 4488 struct umtx_shm_reg **res) 4489 { 4490 struct umtx_shm_reg *reg, *reg1; 4491 struct ucred *cred; 4492 int error; 4493 4494 error = umtx_shm_find_reg(key, res); 4495 if (error != ESRCH) { 4496 /* 4497 * Either no error occured, and '*res' was filled, or EOVERFLOW 4498 * was returned, indicating a reference count limit, and we 4499 * won't create a duplicate registration. In both cases, we are 4500 * done. 4501 */ 4502 return (error); 4503 } 4504 /* No entry, we will create one. */ 4505 4506 cred = td->td_ucred; 4507 if (!chgumtxcnt(cred->cr_ruidinfo, 1, lim_cur(td, RLIMIT_UMTXP))) 4508 return (ENOMEM); 4509 reg = uma_zalloc(umtx_shm_reg_zone, M_WAITOK | M_ZERO); 4510 bcopy(key, ®->ushm_key, sizeof(*key)); 4511 reg->ushm_obj = shm_alloc(td->td_ucred, O_RDWR, false); 4512 reg->ushm_cred = crhold(cred); 4513 error = shm_dotruncate(reg->ushm_obj, PAGE_SIZE); 4514 if (error != 0) { 4515 umtx_shm_free_reg(reg); 4516 return (error); 4517 } 4518 mtx_lock(&umtx_shm_lock); 4519 /* Re-lookup as 'umtx_shm_lock' has been temporarily released. */ 4520 error = umtx_shm_find_reg_locked(key, ®1); 4521 switch (error) { 4522 case 0: 4523 mtx_unlock(&umtx_shm_lock); 4524 umtx_shm_free_reg(reg); 4525 *res = reg1; 4526 return (0); 4527 case ESRCH: 4528 break; 4529 default: 4530 mtx_unlock(&umtx_shm_lock); 4531 umtx_shm_free_reg(reg); 4532 return (error); 4533 } 4534 TAILQ_INSERT_TAIL(&umtx_shm_registry[key->hash], reg, ushm_reg_link); 4535 LIST_INSERT_HEAD(USHM_OBJ_UMTX(key->info.shared.object), reg, 4536 ushm_obj_link); 4537 reg->ushm_flags = USHMF_LINKED; 4538 /* 4539 * This is one reference for the registry and the list of shared 4540 * mutexes referenced by the VM object containing the lock pointer, and 4541 * another for the caller, which it will free after use. So, one of 4542 * these is tied to the presence of USHMF_LINKED. 4543 */ 4544 reg->ushm_refcnt = 2; 4545 mtx_unlock(&umtx_shm_lock); 4546 *res = reg; 4547 return (0); 4548 } 4549 4550 static int 4551 umtx_shm_alive(struct thread *td, void *addr) 4552 { 4553 vm_map_t map; 4554 vm_map_entry_t entry; 4555 vm_object_t object; 4556 vm_pindex_t pindex; 4557 vm_prot_t prot; 4558 int res, ret; 4559 boolean_t wired; 4560 4561 map = &td->td_proc->p_vmspace->vm_map; 4562 res = vm_map_lookup(&map, (uintptr_t)addr, VM_PROT_READ, &entry, 4563 &object, &pindex, &prot, &wired); 4564 if (res != KERN_SUCCESS) 4565 return (EFAULT); 4566 if (object == NULL) 4567 ret = EINVAL; 4568 else 4569 ret = (object->flags & OBJ_UMTXDEAD) != 0 ? ENOTTY : 0; 4570 vm_map_lookup_done(map, entry); 4571 return (ret); 4572 } 4573 4574 static void 4575 umtx_shm_init(void) 4576 { 4577 int i; 4578 4579 umtx_shm_reg_zone = uma_zcreate("umtx_shm", sizeof(struct umtx_shm_reg), 4580 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 4581 mtx_init(&umtx_shm_lock, "umtxshm", NULL, MTX_DEF); 4582 for (i = 0; i < nitems(umtx_shm_registry); i++) 4583 TAILQ_INIT(&umtx_shm_registry[i]); 4584 } 4585 4586 static int 4587 umtx_shm(struct thread *td, void *addr, u_int flags) 4588 { 4589 struct umtx_key key; 4590 struct umtx_shm_reg *reg; 4591 struct file *fp; 4592 int error, fd; 4593 4594 if (__bitcount(flags & (UMTX_SHM_CREAT | UMTX_SHM_LOOKUP | 4595 UMTX_SHM_DESTROY| UMTX_SHM_ALIVE)) != 1) 4596 return (EINVAL); 4597 if ((flags & UMTX_SHM_ALIVE) != 0) 4598 return (umtx_shm_alive(td, addr)); 4599 error = umtx_key_get(addr, TYPE_SHM, PROCESS_SHARE, &key); 4600 if (error != 0) 4601 return (error); 4602 KASSERT(key.shared == 1, ("non-shared key")); 4603 error = (flags & UMTX_SHM_CREAT) != 0 ? 4604 umtx_shm_create_reg(td, &key, ®) : 4605 umtx_shm_find_reg(&key, ®); 4606 umtx_key_release(&key); 4607 if (error != 0) 4608 return (error); 4609 KASSERT(reg != NULL, ("no reg")); 4610 if ((flags & UMTX_SHM_DESTROY) != 0) { 4611 umtx_shm_unref_reg(reg, true); 4612 } else { 4613 #if 0 4614 #ifdef MAC 4615 error = mac_posixshm_check_open(td->td_ucred, 4616 reg->ushm_obj, FFLAGS(O_RDWR)); 4617 if (error == 0) 4618 #endif 4619 error = shm_access(reg->ushm_obj, td->td_ucred, 4620 FFLAGS(O_RDWR)); 4621 if (error == 0) 4622 #endif 4623 error = falloc_caps(td, &fp, &fd, O_CLOEXEC, NULL); 4624 if (error == 0) { 4625 shm_hold(reg->ushm_obj); 4626 finit(fp, FFLAGS(O_RDWR), DTYPE_SHM, reg->ushm_obj, 4627 &shm_ops); 4628 td->td_retval[0] = fd; 4629 fdrop(fp, td); 4630 } 4631 } 4632 umtx_shm_unref_reg(reg, false); 4633 return (error); 4634 } 4635 4636 static int 4637 __umtx_op_shm(struct thread *td, struct _umtx_op_args *uap, 4638 const struct umtx_copyops *ops __unused) 4639 { 4640 4641 return (umtx_shm(td, uap->uaddr1, uap->val)); 4642 } 4643 4644 static int 4645 __umtx_op_robust_lists(struct thread *td, struct _umtx_op_args *uap, 4646 const struct umtx_copyops *ops) 4647 { 4648 struct umtx_robust_lists_params rb; 4649 int error; 4650 4651 if (ops->compat32) { 4652 if ((td->td_pflags2 & TDP2_COMPAT32RB) == 0 && 4653 (td->td_rb_list != 0 || td->td_rbp_list != 0 || 4654 td->td_rb_inact != 0)) 4655 return (EBUSY); 4656 } else if ((td->td_pflags2 & TDP2_COMPAT32RB) != 0) { 4657 return (EBUSY); 4658 } 4659 4660 bzero(&rb, sizeof(rb)); 4661 error = ops->copyin_robust_lists(uap->uaddr1, uap->val, &rb); 4662 if (error != 0) 4663 return (error); 4664 4665 if (ops->compat32) 4666 td->td_pflags2 |= TDP2_COMPAT32RB; 4667 4668 td->td_rb_list = rb.robust_list_offset; 4669 td->td_rbp_list = rb.robust_priv_list_offset; 4670 td->td_rb_inact = rb.robust_inact_offset; 4671 return (0); 4672 } 4673 4674 static int 4675 __umtx_op_get_min_timeout(struct thread *td, struct _umtx_op_args *uap, 4676 const struct umtx_copyops *ops) 4677 { 4678 long val; 4679 int error, val1; 4680 4681 val = sbttons(td->td_proc->p_umtx_min_timeout); 4682 if (ops->compat32) { 4683 val1 = (int)val; 4684 error = copyout(&val1, uap->uaddr1, sizeof(val1)); 4685 } else { 4686 error = copyout(&val, uap->uaddr1, sizeof(val)); 4687 } 4688 return (error); 4689 } 4690 4691 static int 4692 __umtx_op_set_min_timeout(struct thread *td, struct _umtx_op_args *uap, 4693 const struct umtx_copyops *ops) 4694 { 4695 if (uap->val < 0) 4696 return (EINVAL); 4697 td->td_proc->p_umtx_min_timeout = nstosbt(uap->val); 4698 return (0); 4699 } 4700 4701 #if defined(__i386__) || defined(__amd64__) 4702 /* 4703 * Provide the standard 32-bit definitions for x86, since native/compat32 use a 4704 * 32-bit time_t there. Other architectures just need the i386 definitions 4705 * along with their standard compat32. 4706 */ 4707 struct timespecx32 { 4708 int64_t tv_sec; 4709 int32_t tv_nsec; 4710 }; 4711 4712 struct umtx_timex32 { 4713 struct timespecx32 _timeout; 4714 uint32_t _flags; 4715 uint32_t _clockid; 4716 }; 4717 4718 #ifndef __i386__ 4719 #define timespeci386 timespec32 4720 #define umtx_timei386 umtx_time32 4721 #endif 4722 #else /* !__i386__ && !__amd64__ */ 4723 /* 32-bit architectures can emulate i386, so define these almost everywhere. */ 4724 struct timespeci386 { 4725 int32_t tv_sec; 4726 int32_t tv_nsec; 4727 }; 4728 4729 struct umtx_timei386 { 4730 struct timespeci386 _timeout; 4731 uint32_t _flags; 4732 uint32_t _clockid; 4733 }; 4734 4735 #if defined(__LP64__) 4736 #define timespecx32 timespec32 4737 #define umtx_timex32 umtx_time32 4738 #endif 4739 #endif 4740 4741 static int 4742 umtx_copyin_robust_lists32(const void *uaddr, size_t size, 4743 struct umtx_robust_lists_params *rbp) 4744 { 4745 struct umtx_robust_lists_params_compat32 rb32; 4746 int error; 4747 4748 if (size > sizeof(rb32)) 4749 return (EINVAL); 4750 bzero(&rb32, sizeof(rb32)); 4751 error = copyin(uaddr, &rb32, size); 4752 if (error != 0) 4753 return (error); 4754 CP(rb32, *rbp, robust_list_offset); 4755 CP(rb32, *rbp, robust_priv_list_offset); 4756 CP(rb32, *rbp, robust_inact_offset); 4757 return (0); 4758 } 4759 4760 #ifndef __i386__ 4761 static inline int 4762 umtx_copyin_timeouti386(const void *uaddr, struct timespec *tsp) 4763 { 4764 struct timespeci386 ts32; 4765 int error; 4766 4767 error = copyin(uaddr, &ts32, sizeof(ts32)); 4768 if (error == 0) { 4769 if (!timespecvalid_interval(&ts32)) 4770 error = EINVAL; 4771 else { 4772 CP(ts32, *tsp, tv_sec); 4773 CP(ts32, *tsp, tv_nsec); 4774 } 4775 } 4776 return (error); 4777 } 4778 4779 static inline int 4780 umtx_copyin_umtx_timei386(const void *uaddr, size_t size, struct _umtx_time *tp) 4781 { 4782 struct umtx_timei386 t32; 4783 int error; 4784 4785 t32._clockid = CLOCK_REALTIME; 4786 t32._flags = 0; 4787 if (size <= sizeof(t32._timeout)) 4788 error = copyin(uaddr, &t32._timeout, sizeof(t32._timeout)); 4789 else 4790 error = copyin(uaddr, &t32, sizeof(t32)); 4791 if (error != 0) 4792 return (error); 4793 if (!timespecvalid_interval(&t32._timeout)) 4794 return (EINVAL); 4795 TS_CP(t32, *tp, _timeout); 4796 CP(t32, *tp, _flags); 4797 CP(t32, *tp, _clockid); 4798 return (0); 4799 } 4800 4801 static int 4802 umtx_copyout_timeouti386(void *uaddr, size_t sz, struct timespec *tsp) 4803 { 4804 struct timespeci386 remain32 = { 4805 .tv_sec = tsp->tv_sec, 4806 .tv_nsec = tsp->tv_nsec, 4807 }; 4808 4809 /* 4810 * Should be guaranteed by the caller, sz == uaddr1 - sizeof(_umtx_time) 4811 * and we're only called if sz >= sizeof(timespec) as supplied in the 4812 * copyops. 4813 */ 4814 KASSERT(sz >= sizeof(remain32), 4815 ("umtx_copyops specifies incorrect sizes")); 4816 4817 return (copyout(&remain32, uaddr, sizeof(remain32))); 4818 } 4819 #endif /* !__i386__ */ 4820 4821 #if defined(__i386__) || defined(__LP64__) 4822 static inline int 4823 umtx_copyin_timeoutx32(const void *uaddr, struct timespec *tsp) 4824 { 4825 struct timespecx32 ts32; 4826 int error; 4827 4828 error = copyin(uaddr, &ts32, sizeof(ts32)); 4829 if (error == 0) { 4830 if (!timespecvalid_interval(&ts32)) 4831 error = EINVAL; 4832 else { 4833 CP(ts32, *tsp, tv_sec); 4834 CP(ts32, *tsp, tv_nsec); 4835 } 4836 } 4837 return (error); 4838 } 4839 4840 static inline int 4841 umtx_copyin_umtx_timex32(const void *uaddr, size_t size, struct _umtx_time *tp) 4842 { 4843 struct umtx_timex32 t32; 4844 int error; 4845 4846 t32._clockid = CLOCK_REALTIME; 4847 t32._flags = 0; 4848 if (size <= sizeof(t32._timeout)) 4849 error = copyin(uaddr, &t32._timeout, sizeof(t32._timeout)); 4850 else 4851 error = copyin(uaddr, &t32, sizeof(t32)); 4852 if (error != 0) 4853 return (error); 4854 if (!timespecvalid_interval(&t32._timeout)) 4855 return (EINVAL); 4856 TS_CP(t32, *tp, _timeout); 4857 CP(t32, *tp, _flags); 4858 CP(t32, *tp, _clockid); 4859 return (0); 4860 } 4861 4862 static int 4863 umtx_copyout_timeoutx32(void *uaddr, size_t sz, struct timespec *tsp) 4864 { 4865 struct timespecx32 remain32 = { 4866 .tv_sec = tsp->tv_sec, 4867 .tv_nsec = tsp->tv_nsec, 4868 }; 4869 4870 /* 4871 * Should be guaranteed by the caller, sz == uaddr1 - sizeof(_umtx_time) 4872 * and we're only called if sz >= sizeof(timespec) as supplied in the 4873 * copyops. 4874 */ 4875 KASSERT(sz >= sizeof(remain32), 4876 ("umtx_copyops specifies incorrect sizes")); 4877 4878 return (copyout(&remain32, uaddr, sizeof(remain32))); 4879 } 4880 #endif /* __i386__ || __LP64__ */ 4881 4882 typedef int (*_umtx_op_func)(struct thread *td, struct _umtx_op_args *uap, 4883 const struct umtx_copyops *umtx_ops); 4884 4885 static const _umtx_op_func op_table[] = { 4886 #ifdef COMPAT_FREEBSD10 4887 [UMTX_OP_LOCK] = __umtx_op_lock_umtx, 4888 [UMTX_OP_UNLOCK] = __umtx_op_unlock_umtx, 4889 #else 4890 [UMTX_OP_LOCK] = __umtx_op_unimpl, 4891 [UMTX_OP_UNLOCK] = __umtx_op_unimpl, 4892 #endif 4893 [UMTX_OP_WAIT] = __umtx_op_wait, 4894 [UMTX_OP_WAKE] = __umtx_op_wake, 4895 [UMTX_OP_MUTEX_TRYLOCK] = __umtx_op_trylock_umutex, 4896 [UMTX_OP_MUTEX_LOCK] = __umtx_op_lock_umutex, 4897 [UMTX_OP_MUTEX_UNLOCK] = __umtx_op_unlock_umutex, 4898 [UMTX_OP_SET_CEILING] = __umtx_op_set_ceiling, 4899 [UMTX_OP_CV_WAIT] = __umtx_op_cv_wait, 4900 [UMTX_OP_CV_SIGNAL] = __umtx_op_cv_signal, 4901 [UMTX_OP_CV_BROADCAST] = __umtx_op_cv_broadcast, 4902 [UMTX_OP_WAIT_UINT] = __umtx_op_wait_uint, 4903 [UMTX_OP_RW_RDLOCK] = __umtx_op_rw_rdlock, 4904 [UMTX_OP_RW_WRLOCK] = __umtx_op_rw_wrlock, 4905 [UMTX_OP_RW_UNLOCK] = __umtx_op_rw_unlock, 4906 [UMTX_OP_WAIT_UINT_PRIVATE] = __umtx_op_wait_uint_private, 4907 [UMTX_OP_WAKE_PRIVATE] = __umtx_op_wake_private, 4908 [UMTX_OP_MUTEX_WAIT] = __umtx_op_wait_umutex, 4909 [UMTX_OP_MUTEX_WAKE] = __umtx_op_wake_umutex, 4910 #if defined(COMPAT_FREEBSD9) || defined(COMPAT_FREEBSD10) 4911 [UMTX_OP_SEM_WAIT] = __umtx_op_sem_wait, 4912 [UMTX_OP_SEM_WAKE] = __umtx_op_sem_wake, 4913 #else 4914 [UMTX_OP_SEM_WAIT] = __umtx_op_unimpl, 4915 [UMTX_OP_SEM_WAKE] = __umtx_op_unimpl, 4916 #endif 4917 [UMTX_OP_NWAKE_PRIVATE] = __umtx_op_nwake_private, 4918 [UMTX_OP_MUTEX_WAKE2] = __umtx_op_wake2_umutex, 4919 [UMTX_OP_SEM2_WAIT] = __umtx_op_sem2_wait, 4920 [UMTX_OP_SEM2_WAKE] = __umtx_op_sem2_wake, 4921 [UMTX_OP_SHM] = __umtx_op_shm, 4922 [UMTX_OP_ROBUST_LISTS] = __umtx_op_robust_lists, 4923 [UMTX_OP_GET_MIN_TIMEOUT] = __umtx_op_get_min_timeout, 4924 [UMTX_OP_SET_MIN_TIMEOUT] = __umtx_op_set_min_timeout, 4925 }; 4926 4927 static const struct umtx_copyops umtx_native_ops = { 4928 .copyin_timeout = umtx_copyin_timeout, 4929 .copyin_umtx_time = umtx_copyin_umtx_time, 4930 .copyin_robust_lists = umtx_copyin_robust_lists, 4931 .copyout_timeout = umtx_copyout_timeout, 4932 .timespec_sz = sizeof(struct timespec), 4933 .umtx_time_sz = sizeof(struct _umtx_time), 4934 }; 4935 4936 #ifndef __i386__ 4937 static const struct umtx_copyops umtx_native_opsi386 = { 4938 .copyin_timeout = umtx_copyin_timeouti386, 4939 .copyin_umtx_time = umtx_copyin_umtx_timei386, 4940 .copyin_robust_lists = umtx_copyin_robust_lists32, 4941 .copyout_timeout = umtx_copyout_timeouti386, 4942 .timespec_sz = sizeof(struct timespeci386), 4943 .umtx_time_sz = sizeof(struct umtx_timei386), 4944 .compat32 = true, 4945 }; 4946 #endif 4947 4948 #if defined(__i386__) || defined(__LP64__) 4949 /* i386 can emulate other 32-bit archs, too! */ 4950 static const struct umtx_copyops umtx_native_opsx32 = { 4951 .copyin_timeout = umtx_copyin_timeoutx32, 4952 .copyin_umtx_time = umtx_copyin_umtx_timex32, 4953 .copyin_robust_lists = umtx_copyin_robust_lists32, 4954 .copyout_timeout = umtx_copyout_timeoutx32, 4955 .timespec_sz = sizeof(struct timespecx32), 4956 .umtx_time_sz = sizeof(struct umtx_timex32), 4957 .compat32 = true, 4958 }; 4959 4960 #ifdef COMPAT_FREEBSD32 4961 #ifdef __amd64__ 4962 #define umtx_native_ops32 umtx_native_opsi386 4963 #else 4964 #define umtx_native_ops32 umtx_native_opsx32 4965 #endif 4966 #endif /* COMPAT_FREEBSD32 */ 4967 #endif /* __i386__ || __LP64__ */ 4968 4969 #define UMTX_OP__FLAGS (UMTX_OP__32BIT | UMTX_OP__I386) 4970 4971 static int 4972 kern__umtx_op(struct thread *td, void *obj, int op, unsigned long val, 4973 void *uaddr1, void *uaddr2, const struct umtx_copyops *ops) 4974 { 4975 struct _umtx_op_args uap = { 4976 .obj = obj, 4977 .op = op & ~UMTX_OP__FLAGS, 4978 .val = val, 4979 .uaddr1 = uaddr1, 4980 .uaddr2 = uaddr2 4981 }; 4982 4983 if ((uap.op >= nitems(op_table))) 4984 return (EINVAL); 4985 return ((*op_table[uap.op])(td, &uap, ops)); 4986 } 4987 4988 int 4989 sys__umtx_op(struct thread *td, struct _umtx_op_args *uap) 4990 { 4991 static const struct umtx_copyops *umtx_ops; 4992 4993 umtx_ops = &umtx_native_ops; 4994 #ifdef __LP64__ 4995 if ((uap->op & (UMTX_OP__32BIT | UMTX_OP__I386)) != 0) { 4996 if ((uap->op & UMTX_OP__I386) != 0) 4997 umtx_ops = &umtx_native_opsi386; 4998 else 4999 umtx_ops = &umtx_native_opsx32; 5000 } 5001 #elif !defined(__i386__) 5002 /* We consider UMTX_OP__32BIT a nop on !i386 ILP32. */ 5003 if ((uap->op & UMTX_OP__I386) != 0) 5004 umtx_ops = &umtx_native_opsi386; 5005 #else 5006 /* Likewise, UMTX_OP__I386 is a nop on i386. */ 5007 if ((uap->op & UMTX_OP__32BIT) != 0) 5008 umtx_ops = &umtx_native_opsx32; 5009 #endif 5010 return (kern__umtx_op(td, uap->obj, uap->op, uap->val, uap->uaddr1, 5011 uap->uaddr2, umtx_ops)); 5012 } 5013 5014 #ifdef COMPAT_FREEBSD32 5015 #ifdef COMPAT_FREEBSD10 5016 int 5017 freebsd10_freebsd32__umtx_lock(struct thread *td, 5018 struct freebsd10_freebsd32__umtx_lock_args *uap) 5019 { 5020 return (do_lock_umtx32(td, (uint32_t *)uap->umtx, td->td_tid, NULL)); 5021 } 5022 5023 int 5024 freebsd10_freebsd32__umtx_unlock(struct thread *td, 5025 struct freebsd10_freebsd32__umtx_unlock_args *uap) 5026 { 5027 return (do_unlock_umtx32(td, (uint32_t *)uap->umtx, td->td_tid)); 5028 } 5029 #endif /* COMPAT_FREEBSD10 */ 5030 5031 int 5032 freebsd32__umtx_op(struct thread *td, struct freebsd32__umtx_op_args *uap) 5033 { 5034 5035 return (kern__umtx_op(td, uap->obj, uap->op, uap->val, uap->uaddr1, 5036 uap->uaddr2, &umtx_native_ops32)); 5037 } 5038 #endif /* COMPAT_FREEBSD32 */ 5039 5040 void 5041 umtx_thread_init(struct thread *td) 5042 { 5043 5044 td->td_umtxq = umtxq_alloc(); 5045 td->td_umtxq->uq_thread = td; 5046 } 5047 5048 void 5049 umtx_thread_fini(struct thread *td) 5050 { 5051 5052 umtxq_free(td->td_umtxq); 5053 } 5054 5055 /* 5056 * It will be called when new thread is created, e.g fork(). 5057 */ 5058 void 5059 umtx_thread_alloc(struct thread *td) 5060 { 5061 struct umtx_q *uq; 5062 5063 uq = td->td_umtxq; 5064 uq->uq_inherited_pri = PRI_MAX; 5065 5066 KASSERT(uq->uq_flags == 0, ("uq_flags != 0")); 5067 KASSERT(uq->uq_thread == td, ("uq_thread != td")); 5068 KASSERT(uq->uq_pi_blocked == NULL, ("uq_pi_blocked != NULL")); 5069 KASSERT(TAILQ_EMPTY(&uq->uq_pi_contested), ("uq_pi_contested is not empty")); 5070 } 5071 5072 /* 5073 * exec() hook. 5074 * 5075 * Clear robust lists for all process' threads, not delaying the 5076 * cleanup to thread exit, since the relevant address space is 5077 * destroyed right now. 5078 */ 5079 void 5080 umtx_exec(struct proc *p) 5081 { 5082 struct thread *td; 5083 5084 KASSERT(p == curproc, ("need curproc")); 5085 KASSERT((p->p_flag & P_HADTHREADS) == 0 || 5086 (p->p_flag & P_STOPPED_SINGLE) != 0, 5087 ("curproc must be single-threaded")); 5088 /* 5089 * There is no need to lock the list as only this thread can be 5090 * running. 5091 */ 5092 FOREACH_THREAD_IN_PROC(p, td) { 5093 KASSERT(td == curthread || 5094 ((td->td_flags & TDF_BOUNDARY) != 0 && TD_IS_SUSPENDED(td)), 5095 ("running thread %p %p", p, td)); 5096 umtx_thread_cleanup(td); 5097 td->td_rb_list = td->td_rbp_list = td->td_rb_inact = 0; 5098 } 5099 5100 p->p_umtx_min_timeout = 0; 5101 } 5102 5103 /* 5104 * thread exit hook. 5105 */ 5106 void 5107 umtx_thread_exit(struct thread *td) 5108 { 5109 5110 umtx_thread_cleanup(td); 5111 } 5112 5113 static int 5114 umtx_read_uptr(struct thread *td, uintptr_t ptr, uintptr_t *res, bool compat32) 5115 { 5116 u_long res1; 5117 uint32_t res32; 5118 int error; 5119 5120 if (compat32) { 5121 error = fueword32((void *)ptr, &res32); 5122 if (error == 0) 5123 res1 = res32; 5124 } else { 5125 error = fueword((void *)ptr, &res1); 5126 } 5127 if (error == 0) 5128 *res = res1; 5129 else 5130 error = EFAULT; 5131 return (error); 5132 } 5133 5134 static void 5135 umtx_read_rb_list(struct thread *td, struct umutex *m, uintptr_t *rb_list, 5136 bool compat32) 5137 { 5138 struct umutex32 m32; 5139 5140 if (compat32) { 5141 memcpy(&m32, m, sizeof(m32)); 5142 *rb_list = m32.m_rb_lnk; 5143 } else { 5144 *rb_list = m->m_rb_lnk; 5145 } 5146 } 5147 5148 static int 5149 umtx_handle_rb(struct thread *td, uintptr_t rbp, uintptr_t *rb_list, bool inact, 5150 bool compat32) 5151 { 5152 struct umutex m; 5153 int error; 5154 5155 KASSERT(td->td_proc == curproc, ("need current vmspace")); 5156 error = copyin((void *)rbp, &m, sizeof(m)); 5157 if (error != 0) 5158 return (error); 5159 if (rb_list != NULL) 5160 umtx_read_rb_list(td, &m, rb_list, compat32); 5161 if ((m.m_flags & UMUTEX_ROBUST) == 0) 5162 return (EINVAL); 5163 if ((m.m_owner & ~UMUTEX_CONTESTED) != td->td_tid) 5164 /* inact is cleared after unlock, allow the inconsistency */ 5165 return (inact ? 0 : EINVAL); 5166 return (do_unlock_umutex(td, (struct umutex *)rbp, true)); 5167 } 5168 5169 static void 5170 umtx_cleanup_rb_list(struct thread *td, uintptr_t rb_list, uintptr_t *rb_inact, 5171 const char *name, bool compat32) 5172 { 5173 int error, i; 5174 uintptr_t rbp; 5175 bool inact; 5176 5177 if (rb_list == 0) 5178 return; 5179 error = umtx_read_uptr(td, rb_list, &rbp, compat32); 5180 for (i = 0; error == 0 && rbp != 0 && i < umtx_max_rb; i++) { 5181 if (rbp == *rb_inact) { 5182 inact = true; 5183 *rb_inact = 0; 5184 } else 5185 inact = false; 5186 error = umtx_handle_rb(td, rbp, &rbp, inact, compat32); 5187 } 5188 if (i == umtx_max_rb && umtx_verbose_rb) { 5189 uprintf("comm %s pid %d: reached umtx %smax rb %d\n", 5190 td->td_proc->p_comm, td->td_proc->p_pid, name, umtx_max_rb); 5191 } 5192 if (error != 0 && umtx_verbose_rb) { 5193 uprintf("comm %s pid %d: handling %srb error %d\n", 5194 td->td_proc->p_comm, td->td_proc->p_pid, name, error); 5195 } 5196 } 5197 5198 /* 5199 * Clean up umtx data. 5200 */ 5201 static void 5202 umtx_thread_cleanup(struct thread *td) 5203 { 5204 struct umtx_q *uq; 5205 struct umtx_pi *pi; 5206 uintptr_t rb_inact; 5207 bool compat32; 5208 5209 /* 5210 * Disown pi mutexes. 5211 */ 5212 uq = td->td_umtxq; 5213 if (uq != NULL) { 5214 if (uq->uq_inherited_pri != PRI_MAX || 5215 !TAILQ_EMPTY(&uq->uq_pi_contested)) { 5216 mtx_lock(&umtx_lock); 5217 uq->uq_inherited_pri = PRI_MAX; 5218 while ((pi = TAILQ_FIRST(&uq->uq_pi_contested)) != NULL) { 5219 pi->pi_owner = NULL; 5220 TAILQ_REMOVE(&uq->uq_pi_contested, pi, pi_link); 5221 } 5222 mtx_unlock(&umtx_lock); 5223 } 5224 sched_lend_user_prio_cond(td, PRI_MAX); 5225 } 5226 5227 compat32 = (td->td_pflags2 & TDP2_COMPAT32RB) != 0; 5228 td->td_pflags2 &= ~TDP2_COMPAT32RB; 5229 5230 if (td->td_rb_inact == 0 && td->td_rb_list == 0 && td->td_rbp_list == 0) 5231 return; 5232 5233 /* 5234 * Handle terminated robust mutexes. Must be done after 5235 * robust pi disown, otherwise unlock could see unowned 5236 * entries. 5237 */ 5238 rb_inact = td->td_rb_inact; 5239 if (rb_inact != 0) 5240 (void)umtx_read_uptr(td, rb_inact, &rb_inact, compat32); 5241 umtx_cleanup_rb_list(td, td->td_rb_list, &rb_inact, "", compat32); 5242 umtx_cleanup_rb_list(td, td->td_rbp_list, &rb_inact, "priv ", compat32); 5243 if (rb_inact != 0) 5244 (void)umtx_handle_rb(td, rb_inact, NULL, true, compat32); 5245 } 5246