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/vm_map.h> 71 #include <vm/vm_object.h> 72 73 #include <machine/atomic.h> 74 #include <machine/cpu.h> 75 76 #include <compat/freebsd32/freebsd32.h> 77 #ifdef COMPAT_FREEBSD32 78 #include <compat/freebsd32/freebsd32_proto.h> 79 #endif 80 81 #define _UMUTEX_TRY 1 82 #define _UMUTEX_WAIT 2 83 84 #ifdef UMTX_PROFILING 85 #define UPROF_PERC_BIGGER(w, f, sw, sf) \ 86 (((w) > (sw)) || ((w) == (sw) && (f) > (sf))) 87 #endif 88 89 #define UMTXQ_LOCKED_ASSERT(uc) mtx_assert(&(uc)->uc_lock, MA_OWNED) 90 #ifdef INVARIANTS 91 #define UMTXQ_ASSERT_LOCKED_BUSY(key) do { \ 92 struct umtxq_chain *uc; \ 93 \ 94 uc = umtxq_getchain(key); \ 95 mtx_assert(&uc->uc_lock, MA_OWNED); \ 96 KASSERT(uc->uc_busy != 0, ("umtx chain is not busy")); \ 97 } while (0) 98 #else 99 #define UMTXQ_ASSERT_LOCKED_BUSY(key) do {} while (0) 100 #endif 101 102 /* 103 * Don't propagate time-sharing priority, there is a security reason, 104 * a user can simply introduce PI-mutex, let thread A lock the mutex, 105 * and let another thread B block on the mutex, because B is 106 * sleeping, its priority will be boosted, this causes A's priority to 107 * be boosted via priority propagating too and will never be lowered even 108 * if it is using 100%CPU, this is unfair to other processes. 109 */ 110 111 #define UPRI(td) (((td)->td_user_pri >= PRI_MIN_TIMESHARE &&\ 112 (td)->td_user_pri <= PRI_MAX_TIMESHARE) ?\ 113 PRI_MAX_TIMESHARE : (td)->td_user_pri) 114 115 #define GOLDEN_RATIO_PRIME 2654404609U 116 #ifndef UMTX_CHAINS 117 #define UMTX_CHAINS 512 118 #endif 119 #define UMTX_SHIFTS (__WORD_BIT - 9) 120 121 #define GET_SHARE(flags) \ 122 (((flags) & USYNC_PROCESS_SHARED) == 0 ? THREAD_SHARE : PROCESS_SHARE) 123 124 #define BUSY_SPINS 200 125 126 struct umtx_copyops { 127 int (*copyin_timeout)(const void *uaddr, struct timespec *tsp); 128 int (*copyin_umtx_time)(const void *uaddr, size_t size, 129 struct _umtx_time *tp); 130 int (*copyin_robust_lists)(const void *uaddr, size_t size, 131 struct umtx_robust_lists_params *rbp); 132 int (*copyout_timeout)(void *uaddr, size_t size, 133 struct timespec *tsp); 134 const size_t timespec_sz; 135 const size_t umtx_time_sz; 136 const bool compat32; 137 }; 138 139 _Static_assert(sizeof(struct umutex) == sizeof(struct umutex32), "umutex32"); 140 _Static_assert(__offsetof(struct umutex, m_spare[0]) == 141 __offsetof(struct umutex32, m_spare[0]), "m_spare32"); 142 143 int umtx_shm_vnobj_persistent = 0; 144 SYSCTL_INT(_kern_ipc, OID_AUTO, umtx_vnode_persistent, CTLFLAG_RWTUN, 145 &umtx_shm_vnobj_persistent, 0, 146 "False forces destruction of umtx attached to file, on last close"); 147 static int umtx_max_rb = 1000; 148 SYSCTL_INT(_kern_ipc, OID_AUTO, umtx_max_robust, CTLFLAG_RWTUN, 149 &umtx_max_rb, 0, 150 "Maximum number of robust mutexes allowed for each thread"); 151 152 static uma_zone_t umtx_pi_zone; 153 static struct umtxq_chain umtxq_chains[2][UMTX_CHAINS]; 154 static MALLOC_DEFINE(M_UMTX, "umtx", "UMTX queue memory"); 155 static int umtx_pi_allocated; 156 157 static SYSCTL_NODE(_debug, OID_AUTO, umtx, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 158 "umtx debug"); 159 SYSCTL_INT(_debug_umtx, OID_AUTO, umtx_pi_allocated, CTLFLAG_RD, 160 &umtx_pi_allocated, 0, "Allocated umtx_pi"); 161 static int umtx_verbose_rb = 1; 162 SYSCTL_INT(_debug_umtx, OID_AUTO, robust_faults_verbose, CTLFLAG_RWTUN, 163 &umtx_verbose_rb, 0, 164 ""); 165 166 #ifdef UMTX_PROFILING 167 static long max_length; 168 SYSCTL_LONG(_debug_umtx, OID_AUTO, max_length, CTLFLAG_RD, &max_length, 0, "max_length"); 169 static SYSCTL_NODE(_debug_umtx, OID_AUTO, chains, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 170 "umtx chain stats"); 171 #endif 172 173 static inline void umtx_abs_timeout_init2(struct umtx_abs_timeout *timo, 174 const struct _umtx_time *umtxtime); 175 176 static void umtx_shm_init(void); 177 static void umtxq_sysinit(void *); 178 static void umtxq_hash(struct umtx_key *key); 179 static int do_unlock_pp(struct thread *td, struct umutex *m, uint32_t flags, 180 bool rb); 181 static void umtx_thread_cleanup(struct thread *td); 182 SYSINIT(umtx, SI_SUB_EVENTHANDLER+1, SI_ORDER_MIDDLE, umtxq_sysinit, NULL); 183 184 #define umtxq_signal(key, nwake) umtxq_signal_queue((key), (nwake), UMTX_SHARED_QUEUE) 185 186 static struct mtx umtx_lock; 187 188 #ifdef UMTX_PROFILING 189 static void 190 umtx_init_profiling(void) 191 { 192 struct sysctl_oid *chain_oid; 193 char chain_name[10]; 194 int i; 195 196 for (i = 0; i < UMTX_CHAINS; ++i) { 197 snprintf(chain_name, sizeof(chain_name), "%d", i); 198 chain_oid = SYSCTL_ADD_NODE(NULL, 199 SYSCTL_STATIC_CHILDREN(_debug_umtx_chains), OID_AUTO, 200 chain_name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 201 "umtx hash stats"); 202 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(chain_oid), OID_AUTO, 203 "max_length0", CTLFLAG_RD, &umtxq_chains[0][i].max_length, 0, NULL); 204 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(chain_oid), OID_AUTO, 205 "max_length1", CTLFLAG_RD, &umtxq_chains[1][i].max_length, 0, NULL); 206 } 207 } 208 209 static int 210 sysctl_debug_umtx_chains_peaks(SYSCTL_HANDLER_ARGS) 211 { 212 char buf[512]; 213 struct sbuf sb; 214 struct umtxq_chain *uc; 215 u_int fract, i, j, tot, whole; 216 u_int sf0, sf1, sf2, sf3, sf4; 217 u_int si0, si1, si2, si3, si4; 218 u_int sw0, sw1, sw2, sw3, sw4; 219 220 sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN); 221 for (i = 0; i < 2; i++) { 222 tot = 0; 223 for (j = 0; j < UMTX_CHAINS; ++j) { 224 uc = &umtxq_chains[i][j]; 225 mtx_lock(&uc->uc_lock); 226 tot += uc->max_length; 227 mtx_unlock(&uc->uc_lock); 228 } 229 if (tot == 0) 230 sbuf_printf(&sb, "%u) Empty ", i); 231 else { 232 sf0 = sf1 = sf2 = sf3 = sf4 = 0; 233 si0 = si1 = si2 = si3 = si4 = 0; 234 sw0 = sw1 = sw2 = sw3 = sw4 = 0; 235 for (j = 0; j < UMTX_CHAINS; j++) { 236 uc = &umtxq_chains[i][j]; 237 mtx_lock(&uc->uc_lock); 238 whole = uc->max_length * 100; 239 mtx_unlock(&uc->uc_lock); 240 fract = (whole % tot) * 100; 241 if (UPROF_PERC_BIGGER(whole, fract, sw0, sf0)) { 242 sf0 = fract; 243 si0 = j; 244 sw0 = whole; 245 } else if (UPROF_PERC_BIGGER(whole, fract, sw1, 246 sf1)) { 247 sf1 = fract; 248 si1 = j; 249 sw1 = whole; 250 } else if (UPROF_PERC_BIGGER(whole, fract, sw2, 251 sf2)) { 252 sf2 = fract; 253 si2 = j; 254 sw2 = whole; 255 } else if (UPROF_PERC_BIGGER(whole, fract, sw3, 256 sf3)) { 257 sf3 = fract; 258 si3 = j; 259 sw3 = whole; 260 } else if (UPROF_PERC_BIGGER(whole, fract, sw4, 261 sf4)) { 262 sf4 = fract; 263 si4 = j; 264 sw4 = whole; 265 } 266 } 267 sbuf_printf(&sb, "queue %u:\n", i); 268 sbuf_printf(&sb, "1st: %u.%u%% idx: %u\n", sw0 / tot, 269 sf0 / tot, si0); 270 sbuf_printf(&sb, "2nd: %u.%u%% idx: %u\n", sw1 / tot, 271 sf1 / tot, si1); 272 sbuf_printf(&sb, "3rd: %u.%u%% idx: %u\n", sw2 / tot, 273 sf2 / tot, si2); 274 sbuf_printf(&sb, "4th: %u.%u%% idx: %u\n", sw3 / tot, 275 sf3 / tot, si3); 276 sbuf_printf(&sb, "5th: %u.%u%% idx: %u\n", sw4 / tot, 277 sf4 / tot, si4); 278 } 279 } 280 sbuf_trim(&sb); 281 sbuf_finish(&sb); 282 sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req); 283 sbuf_delete(&sb); 284 return (0); 285 } 286 287 static int 288 sysctl_debug_umtx_chains_clear(SYSCTL_HANDLER_ARGS) 289 { 290 struct umtxq_chain *uc; 291 u_int i, j; 292 int clear, error; 293 294 clear = 0; 295 error = sysctl_handle_int(oidp, &clear, 0, req); 296 if (error != 0 || req->newptr == NULL) 297 return (error); 298 299 if (clear != 0) { 300 for (i = 0; i < 2; ++i) { 301 for (j = 0; j < UMTX_CHAINS; ++j) { 302 uc = &umtxq_chains[i][j]; 303 mtx_lock(&uc->uc_lock); 304 uc->length = 0; 305 uc->max_length = 0; 306 mtx_unlock(&uc->uc_lock); 307 } 308 } 309 } 310 return (0); 311 } 312 313 SYSCTL_PROC(_debug_umtx_chains, OID_AUTO, clear, 314 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0, 315 sysctl_debug_umtx_chains_clear, "I", 316 "Clear umtx chains statistics"); 317 SYSCTL_PROC(_debug_umtx_chains, OID_AUTO, peaks, 318 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, 319 sysctl_debug_umtx_chains_peaks, "A", 320 "Highest peaks in chains max length"); 321 #endif 322 323 static void 324 umtxq_sysinit(void *arg __unused) 325 { 326 int i, j; 327 328 umtx_pi_zone = uma_zcreate("umtx pi", sizeof(struct umtx_pi), 329 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 330 for (i = 0; i < 2; ++i) { 331 for (j = 0; j < UMTX_CHAINS; ++j) { 332 mtx_init(&umtxq_chains[i][j].uc_lock, "umtxql", NULL, 333 MTX_DEF | MTX_DUPOK); 334 LIST_INIT(&umtxq_chains[i][j].uc_queue[0]); 335 LIST_INIT(&umtxq_chains[i][j].uc_queue[1]); 336 LIST_INIT(&umtxq_chains[i][j].uc_spare_queue); 337 TAILQ_INIT(&umtxq_chains[i][j].uc_pi_list); 338 umtxq_chains[i][j].uc_busy = 0; 339 umtxq_chains[i][j].uc_waiters = 0; 340 #ifdef UMTX_PROFILING 341 umtxq_chains[i][j].length = 0; 342 umtxq_chains[i][j].max_length = 0; 343 #endif 344 } 345 } 346 #ifdef UMTX_PROFILING 347 umtx_init_profiling(); 348 #endif 349 mtx_init(&umtx_lock, "umtx lock", NULL, MTX_DEF); 350 umtx_shm_init(); 351 } 352 353 struct umtx_q * 354 umtxq_alloc(void) 355 { 356 struct umtx_q *uq; 357 358 uq = malloc(sizeof(struct umtx_q), M_UMTX, M_WAITOK | M_ZERO); 359 uq->uq_spare_queue = malloc(sizeof(struct umtxq_queue), M_UMTX, 360 M_WAITOK | M_ZERO); 361 TAILQ_INIT(&uq->uq_spare_queue->head); 362 TAILQ_INIT(&uq->uq_pi_contested); 363 uq->uq_inherited_pri = PRI_MAX; 364 return (uq); 365 } 366 367 void 368 umtxq_free(struct umtx_q *uq) 369 { 370 371 MPASS(uq->uq_spare_queue != NULL); 372 free(uq->uq_spare_queue, M_UMTX); 373 free(uq, M_UMTX); 374 } 375 376 static inline void 377 umtxq_hash(struct umtx_key *key) 378 { 379 unsigned n; 380 381 n = (uintptr_t)key->info.both.a + key->info.both.b; 382 key->hash = ((n * GOLDEN_RATIO_PRIME) >> UMTX_SHIFTS) % UMTX_CHAINS; 383 } 384 385 struct umtxq_chain * 386 umtxq_getchain(struct umtx_key *key) 387 { 388 389 if (key->type <= TYPE_SEM) 390 return (&umtxq_chains[1][key->hash]); 391 return (&umtxq_chains[0][key->hash]); 392 } 393 394 /* 395 * Set chain to busy state when following operation 396 * may be blocked (kernel mutex can not be used). 397 */ 398 void 399 umtxq_busy(struct umtx_key *key) 400 { 401 struct umtxq_chain *uc; 402 403 uc = umtxq_getchain(key); 404 mtx_assert(&uc->uc_lock, MA_OWNED); 405 if (uc->uc_busy) { 406 #ifdef SMP 407 if (smp_cpus > 1) { 408 int count = BUSY_SPINS; 409 if (count > 0) { 410 umtxq_unlock(key); 411 while (uc->uc_busy && --count > 0) 412 cpu_spinwait(); 413 umtxq_lock(key); 414 } 415 } 416 #endif 417 while (uc->uc_busy) { 418 uc->uc_waiters++; 419 msleep(uc, &uc->uc_lock, 0, "umtxqb", 0); 420 uc->uc_waiters--; 421 } 422 } 423 uc->uc_busy = 1; 424 } 425 426 /* 427 * Unbusy a chain. 428 */ 429 void 430 umtxq_unbusy(struct umtx_key *key) 431 { 432 struct umtxq_chain *uc; 433 434 uc = umtxq_getchain(key); 435 mtx_assert(&uc->uc_lock, MA_OWNED); 436 KASSERT(uc->uc_busy != 0, ("not busy")); 437 uc->uc_busy = 0; 438 if (uc->uc_waiters) 439 wakeup_one(uc); 440 } 441 442 void 443 umtxq_unbusy_unlocked(struct umtx_key *key) 444 { 445 446 umtxq_lock(key); 447 umtxq_unbusy(key); 448 umtxq_unlock(key); 449 } 450 451 static struct umtxq_queue * 452 umtxq_queue_lookup(struct umtx_key *key, int q) 453 { 454 struct umtxq_queue *uh; 455 struct umtxq_chain *uc; 456 457 uc = umtxq_getchain(key); 458 UMTXQ_LOCKED_ASSERT(uc); 459 LIST_FOREACH(uh, &uc->uc_queue[q], link) { 460 if (umtx_key_match(&uh->key, key)) 461 return (uh); 462 } 463 464 return (NULL); 465 } 466 467 void 468 umtxq_insert_queue(struct umtx_q *uq, int q) 469 { 470 struct umtxq_queue *uh; 471 struct umtxq_chain *uc; 472 473 uc = umtxq_getchain(&uq->uq_key); 474 UMTXQ_LOCKED_ASSERT(uc); 475 KASSERT((uq->uq_flags & UQF_UMTXQ) == 0, ("umtx_q is already on queue")); 476 uh = umtxq_queue_lookup(&uq->uq_key, q); 477 if (uh != NULL) { 478 LIST_INSERT_HEAD(&uc->uc_spare_queue, uq->uq_spare_queue, link); 479 } else { 480 uh = uq->uq_spare_queue; 481 uh->key = uq->uq_key; 482 LIST_INSERT_HEAD(&uc->uc_queue[q], uh, link); 483 #ifdef UMTX_PROFILING 484 uc->length++; 485 if (uc->length > uc->max_length) { 486 uc->max_length = uc->length; 487 if (uc->max_length > max_length) 488 max_length = uc->max_length; 489 } 490 #endif 491 } 492 uq->uq_spare_queue = NULL; 493 494 TAILQ_INSERT_TAIL(&uh->head, uq, uq_link); 495 uh->length++; 496 uq->uq_flags |= UQF_UMTXQ; 497 uq->uq_cur_queue = uh; 498 return; 499 } 500 501 void 502 umtxq_remove_queue(struct umtx_q *uq, int q) 503 { 504 struct umtxq_chain *uc; 505 struct umtxq_queue *uh; 506 507 uc = umtxq_getchain(&uq->uq_key); 508 UMTXQ_LOCKED_ASSERT(uc); 509 if (uq->uq_flags & UQF_UMTXQ) { 510 uh = uq->uq_cur_queue; 511 TAILQ_REMOVE(&uh->head, uq, uq_link); 512 uh->length--; 513 uq->uq_flags &= ~UQF_UMTXQ; 514 if (TAILQ_EMPTY(&uh->head)) { 515 KASSERT(uh->length == 0, 516 ("inconsistent umtxq_queue length")); 517 #ifdef UMTX_PROFILING 518 uc->length--; 519 #endif 520 LIST_REMOVE(uh, link); 521 } else { 522 uh = LIST_FIRST(&uc->uc_spare_queue); 523 KASSERT(uh != NULL, ("uc_spare_queue is empty")); 524 LIST_REMOVE(uh, link); 525 } 526 uq->uq_spare_queue = uh; 527 uq->uq_cur_queue = NULL; 528 } 529 } 530 531 /* 532 * Check if there are multiple waiters 533 */ 534 int 535 umtxq_count(struct umtx_key *key) 536 { 537 struct umtxq_queue *uh; 538 539 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 540 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 541 if (uh != NULL) 542 return (uh->length); 543 return (0); 544 } 545 546 /* 547 * Check if there are multiple PI waiters and returns first 548 * waiter. 549 */ 550 static int 551 umtxq_count_pi(struct umtx_key *key, struct umtx_q **first) 552 { 553 struct umtxq_queue *uh; 554 555 *first = NULL; 556 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 557 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 558 if (uh != NULL) { 559 *first = TAILQ_FIRST(&uh->head); 560 return (uh->length); 561 } 562 return (0); 563 } 564 565 /* 566 * Wake up threads waiting on an userland object by a bit mask. 567 */ 568 int 569 umtxq_signal_mask(struct umtx_key *key, int n_wake, u_int bitset) 570 { 571 struct umtxq_queue *uh; 572 struct umtx_q *uq, *uq_temp; 573 int ret; 574 575 ret = 0; 576 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 577 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 578 if (uh == NULL) 579 return (0); 580 TAILQ_FOREACH_SAFE(uq, &uh->head, uq_link, uq_temp) { 581 if ((uq->uq_bitset & bitset) == 0) 582 continue; 583 umtxq_remove_queue(uq, UMTX_SHARED_QUEUE); 584 wakeup_one(uq); 585 if (++ret >= n_wake) 586 break; 587 } 588 return (ret); 589 } 590 591 /* 592 * Wake up threads waiting on an userland object. 593 */ 594 595 static int 596 umtxq_signal_queue(struct umtx_key *key, int n_wake, int q) 597 { 598 struct umtxq_queue *uh; 599 struct umtx_q *uq; 600 int ret; 601 602 ret = 0; 603 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 604 uh = umtxq_queue_lookup(key, q); 605 if (uh != NULL) { 606 while ((uq = TAILQ_FIRST(&uh->head)) != NULL) { 607 umtxq_remove_queue(uq, q); 608 wakeup(uq); 609 if (++ret >= n_wake) 610 return (ret); 611 } 612 } 613 return (ret); 614 } 615 616 /* 617 * Wake up specified thread. 618 */ 619 static inline void 620 umtxq_signal_thread(struct umtx_q *uq) 621 { 622 623 UMTXQ_LOCKED_ASSERT(umtxq_getchain(&uq->uq_key)); 624 umtxq_remove(uq); 625 wakeup(uq); 626 } 627 628 /* 629 * Wake up a maximum of n_wake threads that are waiting on an userland 630 * object identified by key. The remaining threads are removed from queue 631 * identified by key and added to the queue identified by key2 (requeued). 632 * The n_requeue specifies an upper limit on the number of threads that 633 * are requeued to the second queue. 634 */ 635 int 636 umtxq_requeue(struct umtx_key *key, int n_wake, struct umtx_key *key2, 637 int n_requeue) 638 { 639 struct umtxq_queue *uh; 640 struct umtx_q *uq, *uq_temp; 641 int ret; 642 643 ret = 0; 644 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key)); 645 UMTXQ_LOCKED_ASSERT(umtxq_getchain(key2)); 646 uh = umtxq_queue_lookup(key, UMTX_SHARED_QUEUE); 647 if (uh == NULL) 648 return (0); 649 TAILQ_FOREACH_SAFE(uq, &uh->head, uq_link, uq_temp) { 650 if (++ret <= n_wake) { 651 umtxq_remove(uq); 652 wakeup_one(uq); 653 } else { 654 umtxq_remove(uq); 655 uq->uq_key = *key2; 656 umtxq_insert(uq); 657 if (ret - n_wake == n_requeue) 658 break; 659 } 660 } 661 return (ret); 662 } 663 664 static inline int 665 tstohz(const struct timespec *tsp) 666 { 667 struct timeval tv; 668 669 TIMESPEC_TO_TIMEVAL(&tv, tsp); 670 return tvtohz(&tv); 671 } 672 673 void 674 umtx_abs_timeout_init(struct umtx_abs_timeout *timo, int clockid, 675 int absolute, const struct timespec *timeout) 676 { 677 678 timo->clockid = clockid; 679 if (!absolute) { 680 timo->is_abs_real = false; 681 kern_clock_gettime(curthread, timo->clockid, &timo->cur); 682 timespecadd(&timo->cur, timeout, &timo->end); 683 } else { 684 timo->end = *timeout; 685 timo->is_abs_real = clockid == CLOCK_REALTIME || 686 clockid == CLOCK_REALTIME_FAST || 687 clockid == CLOCK_REALTIME_PRECISE || 688 clockid == CLOCK_SECOND; 689 } 690 } 691 692 static void 693 umtx_abs_timeout_init2(struct umtx_abs_timeout *timo, 694 const struct _umtx_time *umtxtime) 695 { 696 697 umtx_abs_timeout_init(timo, umtxtime->_clockid, 698 (umtxtime->_flags & UMTX_ABSTIME) != 0, &umtxtime->_timeout); 699 } 700 701 static void 702 umtx_abs_timeout_enforce_min(sbintime_t *sbt) 703 { 704 sbintime_t when, mint; 705 706 mint = curproc->p_umtx_min_timeout; 707 if (__predict_false(mint != 0)) { 708 when = sbinuptime() + mint; 709 if (*sbt < when) 710 *sbt = when; 711 } 712 } 713 714 static int 715 umtx_abs_timeout_getsbt(struct umtx_abs_timeout *timo, sbintime_t *sbt, 716 int *flags) 717 { 718 struct bintime bt, bbt; 719 struct timespec tts; 720 sbintime_t rem; 721 722 switch (timo->clockid) { 723 724 /* Clocks that can be converted into absolute time. */ 725 case CLOCK_REALTIME: 726 case CLOCK_REALTIME_PRECISE: 727 case CLOCK_REALTIME_FAST: 728 case CLOCK_MONOTONIC: 729 case CLOCK_MONOTONIC_PRECISE: 730 case CLOCK_MONOTONIC_FAST: 731 case CLOCK_UPTIME: 732 case CLOCK_UPTIME_PRECISE: 733 case CLOCK_UPTIME_FAST: 734 case CLOCK_SECOND: 735 timespec2bintime(&timo->end, &bt); 736 switch (timo->clockid) { 737 case CLOCK_REALTIME: 738 case CLOCK_REALTIME_PRECISE: 739 case CLOCK_REALTIME_FAST: 740 case CLOCK_SECOND: 741 getboottimebin(&bbt); 742 bintime_sub(&bt, &bbt); 743 break; 744 } 745 if (bt.sec < 0) 746 return (ETIMEDOUT); 747 if (bt.sec >= (SBT_MAX >> 32)) { 748 *sbt = 0; 749 *flags = 0; 750 return (0); 751 } 752 *sbt = bttosbt(bt); 753 umtx_abs_timeout_enforce_min(sbt); 754 755 /* 756 * Check if the absolute time should be aligned to 757 * avoid firing multiple timer events in non-periodic 758 * timer mode. 759 */ 760 switch (timo->clockid) { 761 case CLOCK_REALTIME_FAST: 762 case CLOCK_MONOTONIC_FAST: 763 case CLOCK_UPTIME_FAST: 764 rem = *sbt % tc_tick_sbt; 765 if (__predict_true(rem != 0)) 766 *sbt += tc_tick_sbt - rem; 767 break; 768 case CLOCK_SECOND: 769 rem = *sbt % SBT_1S; 770 if (__predict_true(rem != 0)) 771 *sbt += SBT_1S - rem; 772 break; 773 } 774 *flags = C_ABSOLUTE; 775 return (0); 776 777 /* Clocks that has to be periodically polled. */ 778 case CLOCK_VIRTUAL: 779 case CLOCK_PROF: 780 case CLOCK_THREAD_CPUTIME_ID: 781 case CLOCK_PROCESS_CPUTIME_ID: 782 default: 783 kern_clock_gettime(curthread, timo->clockid, &timo->cur); 784 if (timespeccmp(&timo->end, &timo->cur, <=)) 785 return (ETIMEDOUT); 786 timespecsub(&timo->end, &timo->cur, &tts); 787 *sbt = tick_sbt * tstohz(&tts); 788 *flags = C_HARDCLOCK; 789 return (0); 790 } 791 } 792 793 static uint32_t 794 umtx_unlock_val(uint32_t flags, bool rb) 795 { 796 797 if (rb) 798 return (UMUTEX_RB_OWNERDEAD); 799 else if ((flags & UMUTEX_NONCONSISTENT) != 0) 800 return (UMUTEX_RB_NOTRECOV); 801 else 802 return (UMUTEX_UNOWNED); 803 804 } 805 806 /* 807 * Put thread into sleep state, before sleeping, check if 808 * thread was removed from umtx queue. 809 */ 810 int 811 umtxq_sleep(struct umtx_q *uq, const char *wmesg, 812 struct umtx_abs_timeout *timo) 813 { 814 struct umtxq_chain *uc; 815 sbintime_t sbt = 0; 816 int error, flags = 0; 817 818 uc = umtxq_getchain(&uq->uq_key); 819 UMTXQ_LOCKED_ASSERT(uc); 820 for (;;) { 821 if (!(uq->uq_flags & UQF_UMTXQ)) { 822 error = 0; 823 break; 824 } 825 if (timo != NULL) { 826 if (timo->is_abs_real) 827 curthread->td_rtcgen = 828 atomic_load_acq_int(&rtc_generation); 829 error = umtx_abs_timeout_getsbt(timo, &sbt, &flags); 830 if (error != 0) 831 break; 832 } 833 error = msleep_sbt(uq, &uc->uc_lock, PCATCH | PDROP, wmesg, 834 sbt, 0, flags); 835 uc = umtxq_getchain(&uq->uq_key); 836 mtx_lock(&uc->uc_lock); 837 if (error == EINTR || error == ERESTART) 838 break; 839 if (error == EWOULDBLOCK && (flags & C_ABSOLUTE) != 0) { 840 error = ETIMEDOUT; 841 break; 842 } 843 } 844 845 curthread->td_rtcgen = 0; 846 return (error); 847 } 848 849 /* 850 * Convert userspace address into unique logical address. 851 */ 852 int 853 umtx_key_get(const void *addr, int type, int share, struct umtx_key *key) 854 { 855 struct thread *td = curthread; 856 vm_map_t map; 857 vm_map_entry_t entry; 858 vm_pindex_t pindex; 859 vm_prot_t prot; 860 boolean_t wired; 861 862 key->type = type; 863 if (share == THREAD_SHARE) { 864 key->shared = 0; 865 key->info.private.vs = td->td_proc->p_vmspace; 866 key->info.private.addr = (uintptr_t)addr; 867 } else { 868 MPASS(share == PROCESS_SHARE || share == AUTO_SHARE); 869 map = &td->td_proc->p_vmspace->vm_map; 870 if (vm_map_lookup(&map, (vm_offset_t)addr, VM_PROT_WRITE, 871 &entry, &key->info.shared.object, &pindex, &prot, 872 &wired) != KERN_SUCCESS) { 873 return (EFAULT); 874 } 875 876 if ((share == PROCESS_SHARE) || 877 (share == AUTO_SHARE && 878 VM_INHERIT_SHARE == entry->inheritance)) { 879 key->shared = 1; 880 key->info.shared.offset = (vm_offset_t)addr - 881 entry->start + entry->offset; 882 vm_object_reference(key->info.shared.object); 883 } else { 884 key->shared = 0; 885 key->info.private.vs = td->td_proc->p_vmspace; 886 key->info.private.addr = (uintptr_t)addr; 887 } 888 vm_map_lookup_done(map, entry); 889 } 890 891 umtxq_hash(key); 892 return (0); 893 } 894 895 /* 896 * Release key. 897 */ 898 void 899 umtx_key_release(struct umtx_key *key) 900 { 901 if (key->shared) 902 vm_object_deallocate(key->info.shared.object); 903 } 904 905 #ifdef COMPAT_FREEBSD10 906 /* 907 * Lock a umtx object. 908 */ 909 static int 910 do_lock_umtx(struct thread *td, struct umtx *umtx, u_long id, 911 const struct timespec *timeout) 912 { 913 struct umtx_abs_timeout timo; 914 struct umtx_q *uq; 915 u_long owner; 916 u_long old; 917 int error = 0; 918 919 uq = td->td_umtxq; 920 if (timeout != NULL) 921 umtx_abs_timeout_init(&timo, CLOCK_REALTIME, 0, timeout); 922 923 /* 924 * Care must be exercised when dealing with umtx structure. It 925 * can fault on any access. 926 */ 927 for (;;) { 928 /* 929 * Try the uncontested case. This should be done in userland. 930 */ 931 owner = casuword(&umtx->u_owner, UMTX_UNOWNED, id); 932 933 /* The acquire succeeded. */ 934 if (owner == UMTX_UNOWNED) 935 return (0); 936 937 /* The address was invalid. */ 938 if (owner == -1) 939 return (EFAULT); 940 941 /* If no one owns it but it is contested try to acquire it. */ 942 if (owner == UMTX_CONTESTED) { 943 owner = casuword(&umtx->u_owner, 944 UMTX_CONTESTED, id | UMTX_CONTESTED); 945 946 if (owner == UMTX_CONTESTED) 947 return (0); 948 949 /* The address was invalid. */ 950 if (owner == -1) 951 return (EFAULT); 952 953 error = thread_check_susp(td, false); 954 if (error != 0) 955 break; 956 957 /* If this failed the lock has changed, restart. */ 958 continue; 959 } 960 961 /* 962 * If we caught a signal, we have retried and now 963 * exit immediately. 964 */ 965 if (error != 0) 966 break; 967 968 if ((error = umtx_key_get(umtx, TYPE_SIMPLE_LOCK, 969 AUTO_SHARE, &uq->uq_key)) != 0) 970 return (error); 971 972 umtxq_lock(&uq->uq_key); 973 umtxq_busy(&uq->uq_key); 974 umtxq_insert(uq); 975 umtxq_unbusy(&uq->uq_key); 976 umtxq_unlock(&uq->uq_key); 977 978 /* 979 * Set the contested bit so that a release in user space 980 * knows to use the system call for unlock. If this fails 981 * either some one else has acquired the lock or it has been 982 * released. 983 */ 984 old = casuword(&umtx->u_owner, owner, owner | UMTX_CONTESTED); 985 986 /* The address was invalid. */ 987 if (old == -1) { 988 umtxq_lock(&uq->uq_key); 989 umtxq_remove(uq); 990 umtxq_unlock(&uq->uq_key); 991 umtx_key_release(&uq->uq_key); 992 return (EFAULT); 993 } 994 995 /* 996 * We set the contested bit, sleep. Otherwise the lock changed 997 * and we need to retry or we lost a race to the thread 998 * unlocking the umtx. 999 */ 1000 umtxq_lock(&uq->uq_key); 1001 if (old == owner) 1002 error = umtxq_sleep(uq, "umtx", timeout == NULL ? NULL : 1003 &timo); 1004 umtxq_remove(uq); 1005 umtxq_unlock(&uq->uq_key); 1006 umtx_key_release(&uq->uq_key); 1007 1008 if (error == 0) 1009 error = thread_check_susp(td, false); 1010 } 1011 1012 if (timeout == NULL) { 1013 /* Mutex locking is restarted if it is interrupted. */ 1014 if (error == EINTR) 1015 error = ERESTART; 1016 } else { 1017 /* Timed-locking is not restarted. */ 1018 if (error == ERESTART) 1019 error = EINTR; 1020 } 1021 return (error); 1022 } 1023 1024 /* 1025 * Unlock a umtx object. 1026 */ 1027 static int 1028 do_unlock_umtx(struct thread *td, struct umtx *umtx, u_long id) 1029 { 1030 struct umtx_key key; 1031 u_long owner; 1032 u_long old; 1033 int error; 1034 int count; 1035 1036 /* 1037 * Make sure we own this mtx. 1038 */ 1039 owner = fuword(__DEVOLATILE(u_long *, &umtx->u_owner)); 1040 if (owner == -1) 1041 return (EFAULT); 1042 1043 if ((owner & ~UMTX_CONTESTED) != id) 1044 return (EPERM); 1045 1046 /* This should be done in userland */ 1047 if ((owner & UMTX_CONTESTED) == 0) { 1048 old = casuword(&umtx->u_owner, owner, UMTX_UNOWNED); 1049 if (old == -1) 1050 return (EFAULT); 1051 if (old == owner) 1052 return (0); 1053 owner = old; 1054 } 1055 1056 /* We should only ever be in here for contested locks */ 1057 if ((error = umtx_key_get(umtx, TYPE_SIMPLE_LOCK, AUTO_SHARE, 1058 &key)) != 0) 1059 return (error); 1060 1061 umtxq_lock(&key); 1062 umtxq_busy(&key); 1063 count = umtxq_count(&key); 1064 umtxq_unlock(&key); 1065 1066 /* 1067 * When unlocking the umtx, it must be marked as unowned if 1068 * there is zero or one thread only waiting for it. 1069 * Otherwise, it must be marked as contested. 1070 */ 1071 old = casuword(&umtx->u_owner, owner, 1072 count <= 1 ? UMTX_UNOWNED : UMTX_CONTESTED); 1073 umtxq_lock(&key); 1074 umtxq_signal(&key,1); 1075 umtxq_unbusy(&key); 1076 umtxq_unlock(&key); 1077 umtx_key_release(&key); 1078 if (old == -1) 1079 return (EFAULT); 1080 if (old != owner) 1081 return (EINVAL); 1082 return (0); 1083 } 1084 1085 #ifdef COMPAT_FREEBSD32 1086 1087 /* 1088 * Lock a umtx object. 1089 */ 1090 static int 1091 do_lock_umtx32(struct thread *td, uint32_t *m, uint32_t id, 1092 const struct timespec *timeout) 1093 { 1094 struct umtx_abs_timeout timo; 1095 struct umtx_q *uq; 1096 uint32_t owner; 1097 uint32_t old; 1098 int error = 0; 1099 1100 uq = td->td_umtxq; 1101 1102 if (timeout != NULL) 1103 umtx_abs_timeout_init(&timo, CLOCK_REALTIME, 0, timeout); 1104 1105 /* 1106 * Care must be exercised when dealing with umtx structure. It 1107 * can fault on any access. 1108 */ 1109 for (;;) { 1110 /* 1111 * Try the uncontested case. This should be done in userland. 1112 */ 1113 owner = casuword32(m, UMUTEX_UNOWNED, id); 1114 1115 /* The acquire succeeded. */ 1116 if (owner == UMUTEX_UNOWNED) 1117 return (0); 1118 1119 /* The address was invalid. */ 1120 if (owner == -1) 1121 return (EFAULT); 1122 1123 /* If no one owns it but it is contested try to acquire it. */ 1124 if (owner == UMUTEX_CONTESTED) { 1125 owner = casuword32(m, 1126 UMUTEX_CONTESTED, id | UMUTEX_CONTESTED); 1127 if (owner == UMUTEX_CONTESTED) 1128 return (0); 1129 1130 /* The address was invalid. */ 1131 if (owner == -1) 1132 return (EFAULT); 1133 1134 error = thread_check_susp(td, false); 1135 if (error != 0) 1136 break; 1137 1138 /* If this failed the lock has changed, restart. */ 1139 continue; 1140 } 1141 1142 /* 1143 * If we caught a signal, we have retried and now 1144 * exit immediately. 1145 */ 1146 if (error != 0) 1147 return (error); 1148 1149 if ((error = umtx_key_get(m, TYPE_SIMPLE_LOCK, 1150 AUTO_SHARE, &uq->uq_key)) != 0) 1151 return (error); 1152 1153 umtxq_lock(&uq->uq_key); 1154 umtxq_busy(&uq->uq_key); 1155 umtxq_insert(uq); 1156 umtxq_unbusy(&uq->uq_key); 1157 umtxq_unlock(&uq->uq_key); 1158 1159 /* 1160 * Set the contested bit so that a release in user space 1161 * knows to use the system call for unlock. If this fails 1162 * either some one else has acquired the lock or it has been 1163 * released. 1164 */ 1165 old = casuword32(m, owner, owner | UMUTEX_CONTESTED); 1166 1167 /* The address was invalid. */ 1168 if (old == -1) { 1169 umtxq_lock(&uq->uq_key); 1170 umtxq_remove(uq); 1171 umtxq_unlock(&uq->uq_key); 1172 umtx_key_release(&uq->uq_key); 1173 return (EFAULT); 1174 } 1175 1176 /* 1177 * We set the contested bit, sleep. Otherwise the lock changed 1178 * and we need to retry or we lost a race to the thread 1179 * unlocking the umtx. 1180 */ 1181 umtxq_lock(&uq->uq_key); 1182 if (old == owner) 1183 error = umtxq_sleep(uq, "umtx", timeout == NULL ? 1184 NULL : &timo); 1185 umtxq_remove(uq); 1186 umtxq_unlock(&uq->uq_key); 1187 umtx_key_release(&uq->uq_key); 1188 1189 if (error == 0) 1190 error = thread_check_susp(td, false); 1191 } 1192 1193 if (timeout == NULL) { 1194 /* Mutex locking is restarted if it is interrupted. */ 1195 if (error == EINTR) 1196 error = ERESTART; 1197 } else { 1198 /* Timed-locking is not restarted. */ 1199 if (error == ERESTART) 1200 error = EINTR; 1201 } 1202 return (error); 1203 } 1204 1205 /* 1206 * Unlock a umtx object. 1207 */ 1208 static int 1209 do_unlock_umtx32(struct thread *td, uint32_t *m, uint32_t id) 1210 { 1211 struct umtx_key key; 1212 uint32_t owner; 1213 uint32_t old; 1214 int error; 1215 int count; 1216 1217 /* 1218 * Make sure we own this mtx. 1219 */ 1220 owner = fuword32(m); 1221 if (owner == -1) 1222 return (EFAULT); 1223 1224 if ((owner & ~UMUTEX_CONTESTED) != id) 1225 return (EPERM); 1226 1227 /* This should be done in userland */ 1228 if ((owner & UMUTEX_CONTESTED) == 0) { 1229 old = casuword32(m, owner, UMUTEX_UNOWNED); 1230 if (old == -1) 1231 return (EFAULT); 1232 if (old == owner) 1233 return (0); 1234 owner = old; 1235 } 1236 1237 /* We should only ever be in here for contested locks */ 1238 if ((error = umtx_key_get(m, TYPE_SIMPLE_LOCK, AUTO_SHARE, 1239 &key)) != 0) 1240 return (error); 1241 1242 umtxq_lock(&key); 1243 umtxq_busy(&key); 1244 count = umtxq_count(&key); 1245 umtxq_unlock(&key); 1246 1247 /* 1248 * When unlocking the umtx, it must be marked as unowned if 1249 * there is zero or one thread only waiting for it. 1250 * Otherwise, it must be marked as contested. 1251 */ 1252 old = casuword32(m, owner, 1253 count <= 1 ? UMUTEX_UNOWNED : UMUTEX_CONTESTED); 1254 umtxq_lock(&key); 1255 umtxq_signal(&key,1); 1256 umtxq_unbusy(&key); 1257 umtxq_unlock(&key); 1258 umtx_key_release(&key); 1259 if (old == -1) 1260 return (EFAULT); 1261 if (old != owner) 1262 return (EINVAL); 1263 return (0); 1264 } 1265 #endif /* COMPAT_FREEBSD32 */ 1266 #endif /* COMPAT_FREEBSD10 */ 1267 1268 /* 1269 * Fetch and compare value, sleep on the address if value is not changed. 1270 */ 1271 static int 1272 do_wait(struct thread *td, void *addr, u_long id, 1273 struct _umtx_time *timeout, int compat32, int is_private) 1274 { 1275 struct umtx_abs_timeout timo; 1276 struct umtx_q *uq; 1277 u_long tmp; 1278 uint32_t tmp32; 1279 int error = 0; 1280 1281 uq = td->td_umtxq; 1282 if ((error = umtx_key_get(addr, TYPE_SIMPLE_WAIT, 1283 is_private ? THREAD_SHARE : AUTO_SHARE, &uq->uq_key)) != 0) 1284 return (error); 1285 1286 if (timeout != NULL) 1287 umtx_abs_timeout_init2(&timo, timeout); 1288 1289 umtxq_lock(&uq->uq_key); 1290 umtxq_insert(uq); 1291 umtxq_unlock(&uq->uq_key); 1292 if (compat32 == 0) { 1293 error = fueword(addr, &tmp); 1294 if (error != 0) 1295 error = EFAULT; 1296 } else { 1297 error = fueword32(addr, &tmp32); 1298 if (error == 0) 1299 tmp = tmp32; 1300 else 1301 error = EFAULT; 1302 } 1303 umtxq_lock(&uq->uq_key); 1304 if (error == 0) { 1305 if (tmp == id) 1306 error = umtxq_sleep(uq, "uwait", timeout == NULL ? 1307 NULL : &timo); 1308 if ((uq->uq_flags & UQF_UMTXQ) == 0) 1309 error = 0; 1310 else 1311 umtxq_remove(uq); 1312 } else if ((uq->uq_flags & UQF_UMTXQ) != 0) { 1313 umtxq_remove(uq); 1314 } 1315 umtxq_unlock(&uq->uq_key); 1316 umtx_key_release(&uq->uq_key); 1317 if (error == ERESTART) 1318 error = EINTR; 1319 return (error); 1320 } 1321 1322 /* 1323 * Wake up threads sleeping on the specified address. 1324 */ 1325 int 1326 kern_umtx_wake(struct thread *td, void *uaddr, int n_wake, int is_private) 1327 { 1328 struct umtx_key key; 1329 int ret; 1330 1331 if ((ret = umtx_key_get(uaddr, TYPE_SIMPLE_WAIT, 1332 is_private ? THREAD_SHARE : AUTO_SHARE, &key)) != 0) 1333 return (ret); 1334 umtxq_lock(&key); 1335 umtxq_signal(&key, n_wake); 1336 umtxq_unlock(&key); 1337 umtx_key_release(&key); 1338 return (0); 1339 } 1340 1341 /* 1342 * Lock PTHREAD_PRIO_NONE protocol POSIX mutex. 1343 */ 1344 static int 1345 do_lock_normal(struct thread *td, struct umutex *m, uint32_t flags, 1346 struct _umtx_time *timeout, int mode) 1347 { 1348 struct umtx_abs_timeout timo; 1349 struct umtx_q *uq; 1350 uint32_t owner, old, id; 1351 int error, rv; 1352 1353 id = td->td_tid; 1354 uq = td->td_umtxq; 1355 error = 0; 1356 if (timeout != NULL) 1357 umtx_abs_timeout_init2(&timo, timeout); 1358 1359 /* 1360 * Care must be exercised when dealing with umtx structure. It 1361 * can fault on any access. 1362 */ 1363 for (;;) { 1364 rv = fueword32(&m->m_owner, &owner); 1365 if (rv == -1) 1366 return (EFAULT); 1367 if (mode == _UMUTEX_WAIT) { 1368 if (owner == UMUTEX_UNOWNED || 1369 owner == UMUTEX_CONTESTED || 1370 owner == UMUTEX_RB_OWNERDEAD || 1371 owner == UMUTEX_RB_NOTRECOV) 1372 return (0); 1373 } else { 1374 /* 1375 * Robust mutex terminated. Kernel duty is to 1376 * return EOWNERDEAD to the userspace. The 1377 * umutex.m_flags UMUTEX_NONCONSISTENT is set 1378 * by the common userspace code. 1379 */ 1380 if (owner == UMUTEX_RB_OWNERDEAD) { 1381 rv = casueword32(&m->m_owner, 1382 UMUTEX_RB_OWNERDEAD, &owner, 1383 id | UMUTEX_CONTESTED); 1384 if (rv == -1) 1385 return (EFAULT); 1386 if (rv == 0) { 1387 MPASS(owner == UMUTEX_RB_OWNERDEAD); 1388 return (EOWNERDEAD); /* success */ 1389 } 1390 MPASS(rv == 1); 1391 rv = thread_check_susp(td, false); 1392 if (rv != 0) 1393 return (rv); 1394 continue; 1395 } 1396 if (owner == UMUTEX_RB_NOTRECOV) 1397 return (ENOTRECOVERABLE); 1398 1399 /* 1400 * Try the uncontested case. This should be 1401 * done in userland. 1402 */ 1403 rv = casueword32(&m->m_owner, UMUTEX_UNOWNED, 1404 &owner, id); 1405 /* The address was invalid. */ 1406 if (rv == -1) 1407 return (EFAULT); 1408 1409 /* The acquire succeeded. */ 1410 if (rv == 0) { 1411 MPASS(owner == UMUTEX_UNOWNED); 1412 return (0); 1413 } 1414 1415 /* 1416 * If no one owns it but it is contested try 1417 * to acquire it. 1418 */ 1419 MPASS(rv == 1); 1420 if (owner == UMUTEX_CONTESTED) { 1421 rv = casueword32(&m->m_owner, 1422 UMUTEX_CONTESTED, &owner, 1423 id | UMUTEX_CONTESTED); 1424 /* The address was invalid. */ 1425 if (rv == -1) 1426 return (EFAULT); 1427 if (rv == 0) { 1428 MPASS(owner == UMUTEX_CONTESTED); 1429 return (0); 1430 } 1431 if (rv == 1) { 1432 rv = thread_check_susp(td, false); 1433 if (rv != 0) 1434 return (rv); 1435 } 1436 1437 /* 1438 * If this failed the lock has 1439 * changed, restart. 1440 */ 1441 continue; 1442 } 1443 1444 /* rv == 1 but not contested, likely store failure */ 1445 rv = thread_check_susp(td, false); 1446 if (rv != 0) 1447 return (rv); 1448 } 1449 1450 if (mode == _UMUTEX_TRY) 1451 return (EBUSY); 1452 1453 /* 1454 * If we caught a signal, we have retried and now 1455 * exit immediately. 1456 */ 1457 if (error != 0) 1458 return (error); 1459 1460 if ((error = umtx_key_get(m, TYPE_NORMAL_UMUTEX, 1461 GET_SHARE(flags), &uq->uq_key)) != 0) 1462 return (error); 1463 1464 umtxq_lock(&uq->uq_key); 1465 umtxq_busy(&uq->uq_key); 1466 umtxq_insert(uq); 1467 umtxq_unlock(&uq->uq_key); 1468 1469 /* 1470 * Set the contested bit so that a release in user space 1471 * knows to use the system call for unlock. If this fails 1472 * either some one else has acquired the lock or it has been 1473 * released. 1474 */ 1475 rv = casueword32(&m->m_owner, owner, &old, 1476 owner | UMUTEX_CONTESTED); 1477 1478 /* The address was invalid or casueword failed to store. */ 1479 if (rv == -1 || rv == 1) { 1480 umtxq_lock(&uq->uq_key); 1481 umtxq_remove(uq); 1482 umtxq_unbusy(&uq->uq_key); 1483 umtxq_unlock(&uq->uq_key); 1484 umtx_key_release(&uq->uq_key); 1485 if (rv == -1) 1486 return (EFAULT); 1487 if (rv == 1) { 1488 rv = thread_check_susp(td, false); 1489 if (rv != 0) 1490 return (rv); 1491 } 1492 continue; 1493 } 1494 1495 /* 1496 * We set the contested bit, sleep. Otherwise the lock changed 1497 * and we need to retry or we lost a race to the thread 1498 * unlocking the umtx. 1499 */ 1500 umtxq_lock(&uq->uq_key); 1501 umtxq_unbusy(&uq->uq_key); 1502 MPASS(old == owner); 1503 error = umtxq_sleep(uq, "umtxn", timeout == NULL ? 1504 NULL : &timo); 1505 umtxq_remove(uq); 1506 umtxq_unlock(&uq->uq_key); 1507 umtx_key_release(&uq->uq_key); 1508 1509 if (error == 0) 1510 error = thread_check_susp(td, false); 1511 } 1512 1513 return (0); 1514 } 1515 1516 /* 1517 * Unlock PTHREAD_PRIO_NONE protocol POSIX mutex. 1518 */ 1519 static int 1520 do_unlock_normal(struct thread *td, struct umutex *m, uint32_t flags, bool rb) 1521 { 1522 struct umtx_key key; 1523 uint32_t owner, old, id, newlock; 1524 int error, count; 1525 1526 id = td->td_tid; 1527 1528 again: 1529 /* 1530 * Make sure we own this mtx. 1531 */ 1532 error = fueword32(&m->m_owner, &owner); 1533 if (error == -1) 1534 return (EFAULT); 1535 1536 if ((owner & ~UMUTEX_CONTESTED) != id) 1537 return (EPERM); 1538 1539 newlock = umtx_unlock_val(flags, rb); 1540 if ((owner & UMUTEX_CONTESTED) == 0) { 1541 error = casueword32(&m->m_owner, owner, &old, newlock); 1542 if (error == -1) 1543 return (EFAULT); 1544 if (error == 1) { 1545 error = thread_check_susp(td, false); 1546 if (error != 0) 1547 return (error); 1548 goto again; 1549 } 1550 MPASS(old == owner); 1551 return (0); 1552 } 1553 1554 /* We should only ever be in here for contested locks */ 1555 if ((error = umtx_key_get(m, TYPE_NORMAL_UMUTEX, GET_SHARE(flags), 1556 &key)) != 0) 1557 return (error); 1558 1559 umtxq_lock(&key); 1560 umtxq_busy(&key); 1561 count = umtxq_count(&key); 1562 umtxq_unlock(&key); 1563 1564 /* 1565 * When unlocking the umtx, it must be marked as unowned if 1566 * there is zero or one thread only waiting for it. 1567 * Otherwise, it must be marked as contested. 1568 */ 1569 if (count > 1) 1570 newlock |= UMUTEX_CONTESTED; 1571 error = casueword32(&m->m_owner, owner, &old, newlock); 1572 umtxq_lock(&key); 1573 umtxq_signal(&key, 1); 1574 umtxq_unbusy(&key); 1575 umtxq_unlock(&key); 1576 umtx_key_release(&key); 1577 if (error == -1) 1578 return (EFAULT); 1579 if (error == 1) { 1580 if (old != owner) 1581 return (EINVAL); 1582 error = thread_check_susp(td, false); 1583 if (error != 0) 1584 return (error); 1585 goto again; 1586 } 1587 return (0); 1588 } 1589 1590 /* 1591 * Check if the mutex is available and wake up a waiter, 1592 * only for simple mutex. 1593 */ 1594 static int 1595 do_wake_umutex(struct thread *td, struct umutex *m) 1596 { 1597 struct umtx_key key; 1598 uint32_t owner; 1599 uint32_t flags; 1600 int error; 1601 int count; 1602 1603 again: 1604 error = fueword32(&m->m_owner, &owner); 1605 if (error == -1) 1606 return (EFAULT); 1607 1608 if ((owner & ~UMUTEX_CONTESTED) != 0 && owner != UMUTEX_RB_OWNERDEAD && 1609 owner != UMUTEX_RB_NOTRECOV) 1610 return (0); 1611 1612 error = fueword32(&m->m_flags, &flags); 1613 if (error == -1) 1614 return (EFAULT); 1615 1616 /* We should only ever be in here for contested locks */ 1617 if ((error = umtx_key_get(m, TYPE_NORMAL_UMUTEX, GET_SHARE(flags), 1618 &key)) != 0) 1619 return (error); 1620 1621 umtxq_lock(&key); 1622 umtxq_busy(&key); 1623 count = umtxq_count(&key); 1624 umtxq_unlock(&key); 1625 1626 if (count <= 1 && owner != UMUTEX_RB_OWNERDEAD && 1627 owner != UMUTEX_RB_NOTRECOV) { 1628 error = casueword32(&m->m_owner, UMUTEX_CONTESTED, &owner, 1629 UMUTEX_UNOWNED); 1630 if (error == -1) { 1631 error = EFAULT; 1632 } else if (error == 1) { 1633 umtxq_lock(&key); 1634 umtxq_unbusy(&key); 1635 umtxq_unlock(&key); 1636 umtx_key_release(&key); 1637 error = thread_check_susp(td, false); 1638 if (error != 0) 1639 return (error); 1640 goto again; 1641 } 1642 } 1643 1644 umtxq_lock(&key); 1645 if (error == 0 && count != 0) { 1646 MPASS((owner & ~UMUTEX_CONTESTED) == 0 || 1647 owner == UMUTEX_RB_OWNERDEAD || 1648 owner == UMUTEX_RB_NOTRECOV); 1649 umtxq_signal(&key, 1); 1650 } 1651 umtxq_unbusy(&key); 1652 umtxq_unlock(&key); 1653 umtx_key_release(&key); 1654 return (error); 1655 } 1656 1657 /* 1658 * Check if the mutex has waiters and tries to fix contention bit. 1659 */ 1660 static int 1661 do_wake2_umutex(struct thread *td, struct umutex *m, uint32_t flags) 1662 { 1663 struct umtx_key key; 1664 uint32_t owner, old; 1665 int type; 1666 int error; 1667 int count; 1668 1669 switch (flags & (UMUTEX_PRIO_INHERIT | UMUTEX_PRIO_PROTECT | 1670 UMUTEX_ROBUST)) { 1671 case 0: 1672 case UMUTEX_ROBUST: 1673 type = TYPE_NORMAL_UMUTEX; 1674 break; 1675 case UMUTEX_PRIO_INHERIT: 1676 type = TYPE_PI_UMUTEX; 1677 break; 1678 case (UMUTEX_PRIO_INHERIT | UMUTEX_ROBUST): 1679 type = TYPE_PI_ROBUST_UMUTEX; 1680 break; 1681 case UMUTEX_PRIO_PROTECT: 1682 type = TYPE_PP_UMUTEX; 1683 break; 1684 case (UMUTEX_PRIO_PROTECT | UMUTEX_ROBUST): 1685 type = TYPE_PP_ROBUST_UMUTEX; 1686 break; 1687 default: 1688 return (EINVAL); 1689 } 1690 if ((error = umtx_key_get(m, type, GET_SHARE(flags), &key)) != 0) 1691 return (error); 1692 1693 owner = 0; 1694 umtxq_lock(&key); 1695 umtxq_busy(&key); 1696 count = umtxq_count(&key); 1697 umtxq_unlock(&key); 1698 1699 error = fueword32(&m->m_owner, &owner); 1700 if (error == -1) 1701 error = EFAULT; 1702 1703 /* 1704 * Only repair contention bit if there is a waiter, this means 1705 * the mutex is still being referenced by userland code, 1706 * otherwise don't update any memory. 1707 */ 1708 while (error == 0 && (owner & UMUTEX_CONTESTED) == 0 && 1709 (count > 1 || (count == 1 && (owner & ~UMUTEX_CONTESTED) != 0))) { 1710 error = casueword32(&m->m_owner, owner, &old, 1711 owner | UMUTEX_CONTESTED); 1712 if (error == -1) { 1713 error = EFAULT; 1714 break; 1715 } 1716 if (error == 0) { 1717 MPASS(old == owner); 1718 break; 1719 } 1720 owner = old; 1721 error = thread_check_susp(td, false); 1722 } 1723 1724 umtxq_lock(&key); 1725 if (error == EFAULT) { 1726 umtxq_signal(&key, INT_MAX); 1727 } else if (count != 0 && ((owner & ~UMUTEX_CONTESTED) == 0 || 1728 owner == UMUTEX_RB_OWNERDEAD || owner == UMUTEX_RB_NOTRECOV)) 1729 umtxq_signal(&key, 1); 1730 umtxq_unbusy(&key); 1731 umtxq_unlock(&key); 1732 umtx_key_release(&key); 1733 return (error); 1734 } 1735 1736 struct umtx_pi * 1737 umtx_pi_alloc(int flags) 1738 { 1739 struct umtx_pi *pi; 1740 1741 pi = uma_zalloc(umtx_pi_zone, M_ZERO | flags); 1742 TAILQ_INIT(&pi->pi_blocked); 1743 atomic_add_int(&umtx_pi_allocated, 1); 1744 return (pi); 1745 } 1746 1747 void 1748 umtx_pi_free(struct umtx_pi *pi) 1749 { 1750 uma_zfree(umtx_pi_zone, pi); 1751 atomic_add_int(&umtx_pi_allocated, -1); 1752 } 1753 1754 /* 1755 * Adjust the thread's position on a pi_state after its priority has been 1756 * changed. 1757 */ 1758 static int 1759 umtx_pi_adjust_thread(struct umtx_pi *pi, struct thread *td) 1760 { 1761 struct umtx_q *uq, *uq1, *uq2; 1762 struct thread *td1; 1763 1764 mtx_assert(&umtx_lock, MA_OWNED); 1765 if (pi == NULL) 1766 return (0); 1767 1768 uq = td->td_umtxq; 1769 1770 /* 1771 * Check if the thread needs to be moved on the blocked chain. 1772 * It needs to be moved if either its priority is lower than 1773 * the previous thread or higher than the next thread. 1774 */ 1775 uq1 = TAILQ_PREV(uq, umtxq_head, uq_lockq); 1776 uq2 = TAILQ_NEXT(uq, uq_lockq); 1777 if ((uq1 != NULL && UPRI(td) < UPRI(uq1->uq_thread)) || 1778 (uq2 != NULL && UPRI(td) > UPRI(uq2->uq_thread))) { 1779 /* 1780 * Remove thread from blocked chain and determine where 1781 * it should be moved to. 1782 */ 1783 TAILQ_REMOVE(&pi->pi_blocked, uq, uq_lockq); 1784 TAILQ_FOREACH(uq1, &pi->pi_blocked, uq_lockq) { 1785 td1 = uq1->uq_thread; 1786 MPASS(td1->td_proc->p_magic == P_MAGIC); 1787 if (UPRI(td1) > UPRI(td)) 1788 break; 1789 } 1790 1791 if (uq1 == NULL) 1792 TAILQ_INSERT_TAIL(&pi->pi_blocked, uq, uq_lockq); 1793 else 1794 TAILQ_INSERT_BEFORE(uq1, uq, uq_lockq); 1795 } 1796 return (1); 1797 } 1798 1799 static struct umtx_pi * 1800 umtx_pi_next(struct umtx_pi *pi) 1801 { 1802 struct umtx_q *uq_owner; 1803 1804 if (pi->pi_owner == NULL) 1805 return (NULL); 1806 uq_owner = pi->pi_owner->td_umtxq; 1807 if (uq_owner == NULL) 1808 return (NULL); 1809 return (uq_owner->uq_pi_blocked); 1810 } 1811 1812 /* 1813 * Floyd's Cycle-Finding Algorithm. 1814 */ 1815 static bool 1816 umtx_pi_check_loop(struct umtx_pi *pi) 1817 { 1818 struct umtx_pi *pi1; /* fast iterator */ 1819 1820 mtx_assert(&umtx_lock, MA_OWNED); 1821 if (pi == NULL) 1822 return (false); 1823 pi1 = pi; 1824 for (;;) { 1825 pi = umtx_pi_next(pi); 1826 if (pi == NULL) 1827 break; 1828 pi1 = umtx_pi_next(pi1); 1829 if (pi1 == NULL) 1830 break; 1831 pi1 = umtx_pi_next(pi1); 1832 if (pi1 == NULL) 1833 break; 1834 if (pi == pi1) 1835 return (true); 1836 } 1837 return (false); 1838 } 1839 1840 /* 1841 * Propagate priority when a thread is blocked on POSIX 1842 * PI mutex. 1843 */ 1844 static void 1845 umtx_propagate_priority(struct thread *td) 1846 { 1847 struct umtx_q *uq; 1848 struct umtx_pi *pi; 1849 int pri; 1850 1851 mtx_assert(&umtx_lock, MA_OWNED); 1852 pri = UPRI(td); 1853 uq = td->td_umtxq; 1854 pi = uq->uq_pi_blocked; 1855 if (pi == NULL) 1856 return; 1857 if (umtx_pi_check_loop(pi)) 1858 return; 1859 1860 for (;;) { 1861 td = pi->pi_owner; 1862 if (td == NULL || td == curthread) 1863 return; 1864 1865 MPASS(td->td_proc != NULL); 1866 MPASS(td->td_proc->p_magic == P_MAGIC); 1867 1868 thread_lock(td); 1869 if (td->td_lend_user_pri > pri) 1870 sched_lend_user_prio(td, pri); 1871 else { 1872 thread_unlock(td); 1873 break; 1874 } 1875 thread_unlock(td); 1876 1877 /* 1878 * Pick up the lock that td is blocked on. 1879 */ 1880 uq = td->td_umtxq; 1881 pi = uq->uq_pi_blocked; 1882 if (pi == NULL) 1883 break; 1884 /* Resort td on the list if needed. */ 1885 umtx_pi_adjust_thread(pi, td); 1886 } 1887 } 1888 1889 /* 1890 * Unpropagate priority for a PI mutex when a thread blocked on 1891 * it is interrupted by signal or resumed by others. 1892 */ 1893 static void 1894 umtx_repropagate_priority(struct umtx_pi *pi) 1895 { 1896 struct umtx_q *uq, *uq_owner; 1897 struct umtx_pi *pi2; 1898 int pri; 1899 1900 mtx_assert(&umtx_lock, MA_OWNED); 1901 1902 if (umtx_pi_check_loop(pi)) 1903 return; 1904 while (pi != NULL && pi->pi_owner != NULL) { 1905 pri = PRI_MAX; 1906 uq_owner = pi->pi_owner->td_umtxq; 1907 1908 TAILQ_FOREACH(pi2, &uq_owner->uq_pi_contested, pi_link) { 1909 uq = TAILQ_FIRST(&pi2->pi_blocked); 1910 if (uq != NULL) { 1911 if (pri > UPRI(uq->uq_thread)) 1912 pri = UPRI(uq->uq_thread); 1913 } 1914 } 1915 1916 if (pri > uq_owner->uq_inherited_pri) 1917 pri = uq_owner->uq_inherited_pri; 1918 thread_lock(pi->pi_owner); 1919 sched_lend_user_prio(pi->pi_owner, pri); 1920 thread_unlock(pi->pi_owner); 1921 if ((pi = uq_owner->uq_pi_blocked) != NULL) 1922 umtx_pi_adjust_thread(pi, uq_owner->uq_thread); 1923 } 1924 } 1925 1926 /* 1927 * Insert a PI mutex into owned list. 1928 */ 1929 static void 1930 umtx_pi_setowner(struct umtx_pi *pi, struct thread *owner) 1931 { 1932 struct umtx_q *uq_owner; 1933 1934 uq_owner = owner->td_umtxq; 1935 mtx_assert(&umtx_lock, MA_OWNED); 1936 MPASS(pi->pi_owner == NULL); 1937 pi->pi_owner = owner; 1938 TAILQ_INSERT_TAIL(&uq_owner->uq_pi_contested, pi, pi_link); 1939 } 1940 1941 /* 1942 * Disown a PI mutex, and remove it from the owned list. 1943 */ 1944 static void 1945 umtx_pi_disown(struct umtx_pi *pi) 1946 { 1947 1948 mtx_assert(&umtx_lock, MA_OWNED); 1949 TAILQ_REMOVE(&pi->pi_owner->td_umtxq->uq_pi_contested, pi, pi_link); 1950 pi->pi_owner = NULL; 1951 } 1952 1953 /* 1954 * Claim ownership of a PI mutex. 1955 */ 1956 int 1957 umtx_pi_claim(struct umtx_pi *pi, struct thread *owner) 1958 { 1959 struct umtx_q *uq; 1960 int pri; 1961 1962 mtx_lock(&umtx_lock); 1963 if (pi->pi_owner == owner) { 1964 mtx_unlock(&umtx_lock); 1965 return (0); 1966 } 1967 1968 if (pi->pi_owner != NULL) { 1969 /* 1970 * userland may have already messed the mutex, sigh. 1971 */ 1972 mtx_unlock(&umtx_lock); 1973 return (EPERM); 1974 } 1975 umtx_pi_setowner(pi, owner); 1976 uq = TAILQ_FIRST(&pi->pi_blocked); 1977 if (uq != NULL) { 1978 pri = UPRI(uq->uq_thread); 1979 thread_lock(owner); 1980 if (pri < UPRI(owner)) 1981 sched_lend_user_prio(owner, pri); 1982 thread_unlock(owner); 1983 } 1984 mtx_unlock(&umtx_lock); 1985 return (0); 1986 } 1987 1988 /* 1989 * Adjust a thread's order position in its blocked PI mutex, 1990 * this may result new priority propagating process. 1991 */ 1992 void 1993 umtx_pi_adjust(struct thread *td, u_char oldpri) 1994 { 1995 struct umtx_q *uq; 1996 struct umtx_pi *pi; 1997 1998 uq = td->td_umtxq; 1999 mtx_lock(&umtx_lock); 2000 /* 2001 * Pick up the lock that td is blocked on. 2002 */ 2003 pi = uq->uq_pi_blocked; 2004 if (pi != NULL) { 2005 umtx_pi_adjust_thread(pi, td); 2006 umtx_repropagate_priority(pi); 2007 } 2008 mtx_unlock(&umtx_lock); 2009 } 2010 2011 /* 2012 * Sleep on a PI mutex. 2013 */ 2014 int 2015 umtxq_sleep_pi(struct umtx_q *uq, struct umtx_pi *pi, uint32_t owner, 2016 const char *wmesg, struct umtx_abs_timeout *timo, bool shared) 2017 { 2018 struct thread *td, *td1; 2019 struct umtx_q *uq1; 2020 int error, pri; 2021 #ifdef INVARIANTS 2022 struct umtxq_chain *uc; 2023 2024 uc = umtxq_getchain(&pi->pi_key); 2025 #endif 2026 error = 0; 2027 td = uq->uq_thread; 2028 KASSERT(td == curthread, ("inconsistent uq_thread")); 2029 UMTXQ_LOCKED_ASSERT(umtxq_getchain(&uq->uq_key)); 2030 KASSERT(uc->uc_busy != 0, ("umtx chain is not busy")); 2031 umtxq_insert(uq); 2032 mtx_lock(&umtx_lock); 2033 if (pi->pi_owner == NULL) { 2034 mtx_unlock(&umtx_lock); 2035 td1 = tdfind(owner, shared ? -1 : td->td_proc->p_pid); 2036 mtx_lock(&umtx_lock); 2037 if (td1 != NULL) { 2038 if (pi->pi_owner == NULL) 2039 umtx_pi_setowner(pi, td1); 2040 PROC_UNLOCK(td1->td_proc); 2041 } 2042 } 2043 2044 TAILQ_FOREACH(uq1, &pi->pi_blocked, uq_lockq) { 2045 pri = UPRI(uq1->uq_thread); 2046 if (pri > UPRI(td)) 2047 break; 2048 } 2049 2050 if (uq1 != NULL) 2051 TAILQ_INSERT_BEFORE(uq1, uq, uq_lockq); 2052 else 2053 TAILQ_INSERT_TAIL(&pi->pi_blocked, uq, uq_lockq); 2054 2055 uq->uq_pi_blocked = pi; 2056 thread_lock(td); 2057 td->td_flags |= TDF_UPIBLOCKED; 2058 thread_unlock(td); 2059 umtx_propagate_priority(td); 2060 mtx_unlock(&umtx_lock); 2061 umtxq_unbusy(&uq->uq_key); 2062 2063 error = umtxq_sleep(uq, wmesg, timo); 2064 umtxq_remove(uq); 2065 2066 mtx_lock(&umtx_lock); 2067 uq->uq_pi_blocked = NULL; 2068 thread_lock(td); 2069 td->td_flags &= ~TDF_UPIBLOCKED; 2070 thread_unlock(td); 2071 TAILQ_REMOVE(&pi->pi_blocked, uq, uq_lockq); 2072 umtx_repropagate_priority(pi); 2073 mtx_unlock(&umtx_lock); 2074 umtxq_unlock(&uq->uq_key); 2075 2076 return (error); 2077 } 2078 2079 /* 2080 * Add reference count for a PI mutex. 2081 */ 2082 void 2083 umtx_pi_ref(struct umtx_pi *pi) 2084 { 2085 2086 UMTXQ_LOCKED_ASSERT(umtxq_getchain(&pi->pi_key)); 2087 pi->pi_refcount++; 2088 } 2089 2090 /* 2091 * Decrease reference count for a PI mutex, if the counter 2092 * is decreased to zero, its memory space is freed. 2093 */ 2094 void 2095 umtx_pi_unref(struct umtx_pi *pi) 2096 { 2097 struct umtxq_chain *uc; 2098 2099 uc = umtxq_getchain(&pi->pi_key); 2100 UMTXQ_LOCKED_ASSERT(uc); 2101 KASSERT(pi->pi_refcount > 0, ("invalid reference count")); 2102 if (--pi->pi_refcount == 0) { 2103 mtx_lock(&umtx_lock); 2104 if (pi->pi_owner != NULL) 2105 umtx_pi_disown(pi); 2106 KASSERT(TAILQ_EMPTY(&pi->pi_blocked), 2107 ("blocked queue not empty")); 2108 mtx_unlock(&umtx_lock); 2109 TAILQ_REMOVE(&uc->uc_pi_list, pi, pi_hashlink); 2110 umtx_pi_free(pi); 2111 } 2112 } 2113 2114 /* 2115 * Find a PI mutex in hash table. 2116 */ 2117 struct umtx_pi * 2118 umtx_pi_lookup(struct umtx_key *key) 2119 { 2120 struct umtxq_chain *uc; 2121 struct umtx_pi *pi; 2122 2123 uc = umtxq_getchain(key); 2124 UMTXQ_LOCKED_ASSERT(uc); 2125 2126 TAILQ_FOREACH(pi, &uc->uc_pi_list, pi_hashlink) { 2127 if (umtx_key_match(&pi->pi_key, key)) { 2128 return (pi); 2129 } 2130 } 2131 return (NULL); 2132 } 2133 2134 /* 2135 * Insert a PI mutex into hash table. 2136 */ 2137 void 2138 umtx_pi_insert(struct umtx_pi *pi) 2139 { 2140 struct umtxq_chain *uc; 2141 2142 uc = umtxq_getchain(&pi->pi_key); 2143 UMTXQ_LOCKED_ASSERT(uc); 2144 TAILQ_INSERT_TAIL(&uc->uc_pi_list, pi, pi_hashlink); 2145 } 2146 2147 /* 2148 * Drop a PI mutex and wakeup a top waiter. 2149 */ 2150 int 2151 umtx_pi_drop(struct thread *td, struct umtx_key *key, bool rb, int *count) 2152 { 2153 struct umtx_q *uq_first, *uq_first2, *uq_me; 2154 struct umtx_pi *pi, *pi2; 2155 int pri; 2156 2157 UMTXQ_ASSERT_LOCKED_BUSY(key); 2158 *count = umtxq_count_pi(key, &uq_first); 2159 if (uq_first != NULL) { 2160 mtx_lock(&umtx_lock); 2161 pi = uq_first->uq_pi_blocked; 2162 KASSERT(pi != NULL, ("pi == NULL?")); 2163 if (pi->pi_owner != td && !(rb && pi->pi_owner == NULL)) { 2164 mtx_unlock(&umtx_lock); 2165 /* userland messed the mutex */ 2166 return (EPERM); 2167 } 2168 uq_me = td->td_umtxq; 2169 if (pi->pi_owner == td) 2170 umtx_pi_disown(pi); 2171 /* get highest priority thread which is still sleeping. */ 2172 uq_first = TAILQ_FIRST(&pi->pi_blocked); 2173 while (uq_first != NULL && 2174 (uq_first->uq_flags & UQF_UMTXQ) == 0) { 2175 uq_first = TAILQ_NEXT(uq_first, uq_lockq); 2176 } 2177 pri = PRI_MAX; 2178 TAILQ_FOREACH(pi2, &uq_me->uq_pi_contested, pi_link) { 2179 uq_first2 = TAILQ_FIRST(&pi2->pi_blocked); 2180 if (uq_first2 != NULL) { 2181 if (pri > UPRI(uq_first2->uq_thread)) 2182 pri = UPRI(uq_first2->uq_thread); 2183 } 2184 } 2185 thread_lock(td); 2186 sched_lend_user_prio(td, pri); 2187 thread_unlock(td); 2188 mtx_unlock(&umtx_lock); 2189 if (uq_first) 2190 umtxq_signal_thread(uq_first); 2191 } else { 2192 pi = umtx_pi_lookup(key); 2193 /* 2194 * A umtx_pi can exist if a signal or timeout removed the 2195 * last waiter from the umtxq, but there is still 2196 * a thread in do_lock_pi() holding the umtx_pi. 2197 */ 2198 if (pi != NULL) { 2199 /* 2200 * The umtx_pi can be unowned, such as when a thread 2201 * has just entered do_lock_pi(), allocated the 2202 * umtx_pi, and unlocked the umtxq. 2203 * If the current thread owns it, it must disown it. 2204 */ 2205 mtx_lock(&umtx_lock); 2206 if (pi->pi_owner == td) 2207 umtx_pi_disown(pi); 2208 mtx_unlock(&umtx_lock); 2209 } 2210 } 2211 return (0); 2212 } 2213 2214 /* 2215 * Lock a PI mutex. 2216 */ 2217 static int 2218 do_lock_pi(struct thread *td, struct umutex *m, uint32_t flags, 2219 struct _umtx_time *timeout, int try) 2220 { 2221 struct umtx_abs_timeout timo; 2222 struct umtx_q *uq; 2223 struct umtx_pi *pi, *new_pi; 2224 uint32_t id, old_owner, owner, old; 2225 int error, rv; 2226 2227 id = td->td_tid; 2228 uq = td->td_umtxq; 2229 2230 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2231 TYPE_PI_ROBUST_UMUTEX : TYPE_PI_UMUTEX, GET_SHARE(flags), 2232 &uq->uq_key)) != 0) 2233 return (error); 2234 2235 if (timeout != NULL) 2236 umtx_abs_timeout_init2(&timo, timeout); 2237 2238 umtxq_lock(&uq->uq_key); 2239 pi = umtx_pi_lookup(&uq->uq_key); 2240 if (pi == NULL) { 2241 new_pi = umtx_pi_alloc(M_NOWAIT); 2242 if (new_pi == NULL) { 2243 umtxq_unlock(&uq->uq_key); 2244 new_pi = umtx_pi_alloc(M_WAITOK); 2245 umtxq_lock(&uq->uq_key); 2246 pi = umtx_pi_lookup(&uq->uq_key); 2247 if (pi != NULL) { 2248 umtx_pi_free(new_pi); 2249 new_pi = NULL; 2250 } 2251 } 2252 if (new_pi != NULL) { 2253 new_pi->pi_key = uq->uq_key; 2254 umtx_pi_insert(new_pi); 2255 pi = new_pi; 2256 } 2257 } 2258 umtx_pi_ref(pi); 2259 umtxq_unlock(&uq->uq_key); 2260 2261 /* 2262 * Care must be exercised when dealing with umtx structure. It 2263 * can fault on any access. 2264 */ 2265 for (;;) { 2266 /* 2267 * Try the uncontested case. This should be done in userland. 2268 */ 2269 rv = casueword32(&m->m_owner, UMUTEX_UNOWNED, &owner, id); 2270 /* The address was invalid. */ 2271 if (rv == -1) { 2272 error = EFAULT; 2273 break; 2274 } 2275 /* The acquire succeeded. */ 2276 if (rv == 0) { 2277 MPASS(owner == UMUTEX_UNOWNED); 2278 error = 0; 2279 break; 2280 } 2281 2282 if (owner == UMUTEX_RB_NOTRECOV) { 2283 error = ENOTRECOVERABLE; 2284 break; 2285 } 2286 2287 /* 2288 * Nobody owns it, but the acquire failed. This can happen 2289 * with ll/sc atomics. 2290 */ 2291 if (owner == UMUTEX_UNOWNED) { 2292 error = thread_check_susp(td, true); 2293 if (error != 0) 2294 break; 2295 continue; 2296 } 2297 2298 /* 2299 * Avoid overwriting a possible error from sleep due 2300 * to the pending signal with suspension check result. 2301 */ 2302 if (error == 0) { 2303 error = thread_check_susp(td, true); 2304 if (error != 0) 2305 break; 2306 } 2307 2308 /* If no one owns it but it is contested try to acquire it. */ 2309 if (owner == UMUTEX_CONTESTED || owner == UMUTEX_RB_OWNERDEAD) { 2310 old_owner = owner; 2311 rv = casueword32(&m->m_owner, owner, &owner, 2312 id | UMUTEX_CONTESTED); 2313 /* The address was invalid. */ 2314 if (rv == -1) { 2315 error = EFAULT; 2316 break; 2317 } 2318 if (rv == 1) { 2319 if (error == 0) { 2320 error = thread_check_susp(td, true); 2321 if (error != 0) 2322 break; 2323 } 2324 2325 /* 2326 * If this failed the lock could 2327 * changed, restart. 2328 */ 2329 continue; 2330 } 2331 2332 MPASS(rv == 0); 2333 MPASS(owner == old_owner); 2334 umtxq_lock(&uq->uq_key); 2335 umtxq_busy(&uq->uq_key); 2336 error = umtx_pi_claim(pi, td); 2337 umtxq_unbusy(&uq->uq_key); 2338 umtxq_unlock(&uq->uq_key); 2339 if (error != 0) { 2340 /* 2341 * Since we're going to return an 2342 * error, restore the m_owner to its 2343 * previous, unowned state to avoid 2344 * compounding the problem. 2345 */ 2346 (void)casuword32(&m->m_owner, 2347 id | UMUTEX_CONTESTED, old_owner); 2348 } 2349 if (error == 0 && old_owner == UMUTEX_RB_OWNERDEAD) 2350 error = EOWNERDEAD; 2351 break; 2352 } 2353 2354 if ((owner & ~UMUTEX_CONTESTED) == id) { 2355 error = EDEADLK; 2356 break; 2357 } 2358 2359 if (try != 0) { 2360 error = EBUSY; 2361 break; 2362 } 2363 2364 /* 2365 * If we caught a signal, we have retried and now 2366 * exit immediately. 2367 */ 2368 if (error != 0) 2369 break; 2370 2371 umtxq_lock(&uq->uq_key); 2372 umtxq_busy(&uq->uq_key); 2373 umtxq_unlock(&uq->uq_key); 2374 2375 /* 2376 * Set the contested bit so that a release in user space 2377 * knows to use the system call for unlock. If this fails 2378 * either some one else has acquired the lock or it has been 2379 * released. 2380 */ 2381 rv = casueword32(&m->m_owner, owner, &old, owner | 2382 UMUTEX_CONTESTED); 2383 2384 /* The address was invalid. */ 2385 if (rv == -1) { 2386 umtxq_unbusy_unlocked(&uq->uq_key); 2387 error = EFAULT; 2388 break; 2389 } 2390 if (rv == 1) { 2391 umtxq_unbusy_unlocked(&uq->uq_key); 2392 error = thread_check_susp(td, true); 2393 if (error != 0) 2394 break; 2395 2396 /* 2397 * The lock changed and we need to retry or we 2398 * lost a race to the thread unlocking the 2399 * umtx. Note that the UMUTEX_RB_OWNERDEAD 2400 * value for owner is impossible there. 2401 */ 2402 continue; 2403 } 2404 2405 umtxq_lock(&uq->uq_key); 2406 2407 /* We set the contested bit, sleep. */ 2408 MPASS(old == owner); 2409 error = umtxq_sleep_pi(uq, pi, owner & ~UMUTEX_CONTESTED, 2410 "umtxpi", timeout == NULL ? NULL : &timo, 2411 (flags & USYNC_PROCESS_SHARED) != 0); 2412 if (error != 0) 2413 continue; 2414 2415 error = thread_check_susp(td, false); 2416 if (error != 0) 2417 break; 2418 } 2419 2420 umtxq_lock(&uq->uq_key); 2421 umtx_pi_unref(pi); 2422 umtxq_unlock(&uq->uq_key); 2423 2424 umtx_key_release(&uq->uq_key); 2425 return (error); 2426 } 2427 2428 /* 2429 * Unlock a PI mutex. 2430 */ 2431 static int 2432 do_unlock_pi(struct thread *td, struct umutex *m, uint32_t flags, bool rb) 2433 { 2434 struct umtx_key key; 2435 uint32_t id, new_owner, old, owner; 2436 int count, error; 2437 2438 id = td->td_tid; 2439 2440 usrloop: 2441 /* 2442 * Make sure we own this mtx. 2443 */ 2444 error = fueword32(&m->m_owner, &owner); 2445 if (error == -1) 2446 return (EFAULT); 2447 2448 if ((owner & ~UMUTEX_CONTESTED) != id) 2449 return (EPERM); 2450 2451 new_owner = umtx_unlock_val(flags, rb); 2452 2453 /* This should be done in userland */ 2454 if ((owner & UMUTEX_CONTESTED) == 0) { 2455 error = casueword32(&m->m_owner, owner, &old, new_owner); 2456 if (error == -1) 2457 return (EFAULT); 2458 if (error == 1) { 2459 error = thread_check_susp(td, true); 2460 if (error != 0) 2461 return (error); 2462 goto usrloop; 2463 } 2464 if (old == owner) 2465 return (0); 2466 owner = old; 2467 } 2468 2469 /* We should only ever be in here for contested locks */ 2470 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2471 TYPE_PI_ROBUST_UMUTEX : TYPE_PI_UMUTEX, GET_SHARE(flags), 2472 &key)) != 0) 2473 return (error); 2474 2475 umtxq_lock(&key); 2476 umtxq_busy(&key); 2477 error = umtx_pi_drop(td, &key, rb, &count); 2478 if (error != 0) { 2479 umtxq_unbusy(&key); 2480 umtxq_unlock(&key); 2481 umtx_key_release(&key); 2482 /* userland messed the mutex */ 2483 return (error); 2484 } 2485 umtxq_unlock(&key); 2486 2487 /* 2488 * When unlocking the umtx, it must be marked as unowned if 2489 * there is zero or one thread only waiting for it. 2490 * Otherwise, it must be marked as contested. 2491 */ 2492 2493 if (count > 1) 2494 new_owner |= UMUTEX_CONTESTED; 2495 again: 2496 error = casueword32(&m->m_owner, owner, &old, new_owner); 2497 if (error == 1) { 2498 error = thread_check_susp(td, false); 2499 if (error == 0) 2500 goto again; 2501 } 2502 umtxq_unbusy_unlocked(&key); 2503 umtx_key_release(&key); 2504 if (error == -1) 2505 return (EFAULT); 2506 if (error == 0 && old != owner) 2507 return (EINVAL); 2508 return (error); 2509 } 2510 2511 /* 2512 * Lock a PP mutex. 2513 */ 2514 static int 2515 do_lock_pp(struct thread *td, struct umutex *m, uint32_t flags, 2516 struct _umtx_time *timeout, int try) 2517 { 2518 struct umtx_abs_timeout timo; 2519 struct umtx_q *uq, *uq2; 2520 struct umtx_pi *pi; 2521 uint32_t ceiling; 2522 uint32_t owner, id; 2523 int error, pri, old_inherited_pri, su, rv; 2524 2525 id = td->td_tid; 2526 uq = td->td_umtxq; 2527 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2528 TYPE_PP_ROBUST_UMUTEX : TYPE_PP_UMUTEX, GET_SHARE(flags), 2529 &uq->uq_key)) != 0) 2530 return (error); 2531 2532 if (timeout != NULL) 2533 umtx_abs_timeout_init2(&timo, timeout); 2534 2535 su = (priv_check(td, PRIV_SCHED_RTPRIO) == 0); 2536 for (;;) { 2537 old_inherited_pri = uq->uq_inherited_pri; 2538 umtxq_lock(&uq->uq_key); 2539 umtxq_busy(&uq->uq_key); 2540 umtxq_unlock(&uq->uq_key); 2541 2542 rv = fueword32(&m->m_ceilings[0], &ceiling); 2543 if (rv == -1) { 2544 error = EFAULT; 2545 goto out; 2546 } 2547 ceiling = RTP_PRIO_MAX - ceiling; 2548 if (ceiling > RTP_PRIO_MAX) { 2549 error = EINVAL; 2550 goto out; 2551 } 2552 2553 mtx_lock(&umtx_lock); 2554 if (UPRI(td) < PRI_MIN_REALTIME + ceiling) { 2555 mtx_unlock(&umtx_lock); 2556 error = EINVAL; 2557 goto out; 2558 } 2559 if (su && PRI_MIN_REALTIME + ceiling < uq->uq_inherited_pri) { 2560 uq->uq_inherited_pri = PRI_MIN_REALTIME + ceiling; 2561 thread_lock(td); 2562 if (uq->uq_inherited_pri < UPRI(td)) 2563 sched_lend_user_prio(td, uq->uq_inherited_pri); 2564 thread_unlock(td); 2565 } 2566 mtx_unlock(&umtx_lock); 2567 2568 rv = casueword32(&m->m_owner, UMUTEX_CONTESTED, &owner, 2569 id | UMUTEX_CONTESTED); 2570 /* The address was invalid. */ 2571 if (rv == -1) { 2572 error = EFAULT; 2573 break; 2574 } 2575 if (rv == 0) { 2576 MPASS(owner == UMUTEX_CONTESTED); 2577 error = 0; 2578 break; 2579 } 2580 /* rv == 1 */ 2581 if (owner == UMUTEX_RB_OWNERDEAD) { 2582 rv = casueword32(&m->m_owner, UMUTEX_RB_OWNERDEAD, 2583 &owner, id | UMUTEX_CONTESTED); 2584 if (rv == -1) { 2585 error = EFAULT; 2586 break; 2587 } 2588 if (rv == 0) { 2589 MPASS(owner == UMUTEX_RB_OWNERDEAD); 2590 error = EOWNERDEAD; /* success */ 2591 break; 2592 } 2593 2594 /* 2595 * rv == 1, only check for suspension if we 2596 * did not already catched a signal. If we 2597 * get an error from the check, the same 2598 * condition is checked by the umtxq_sleep() 2599 * call below, so we should obliterate the 2600 * error to not skip the last loop iteration. 2601 */ 2602 if (error == 0) { 2603 error = thread_check_susp(td, false); 2604 if (error == 0) { 2605 if (try != 0) 2606 error = EBUSY; 2607 else 2608 continue; 2609 } 2610 error = 0; 2611 } 2612 } else if (owner == UMUTEX_RB_NOTRECOV) { 2613 error = ENOTRECOVERABLE; 2614 } 2615 2616 if (try != 0) 2617 error = EBUSY; 2618 2619 /* 2620 * If we caught a signal, we have retried and now 2621 * exit immediately. 2622 */ 2623 if (error != 0) 2624 break; 2625 2626 umtxq_lock(&uq->uq_key); 2627 umtxq_insert(uq); 2628 umtxq_unbusy(&uq->uq_key); 2629 error = umtxq_sleep(uq, "umtxpp", timeout == NULL ? 2630 NULL : &timo); 2631 umtxq_remove(uq); 2632 umtxq_unlock(&uq->uq_key); 2633 2634 mtx_lock(&umtx_lock); 2635 uq->uq_inherited_pri = old_inherited_pri; 2636 pri = PRI_MAX; 2637 TAILQ_FOREACH(pi, &uq->uq_pi_contested, pi_link) { 2638 uq2 = TAILQ_FIRST(&pi->pi_blocked); 2639 if (uq2 != NULL) { 2640 if (pri > UPRI(uq2->uq_thread)) 2641 pri = UPRI(uq2->uq_thread); 2642 } 2643 } 2644 if (pri > uq->uq_inherited_pri) 2645 pri = uq->uq_inherited_pri; 2646 thread_lock(td); 2647 sched_lend_user_prio(td, pri); 2648 thread_unlock(td); 2649 mtx_unlock(&umtx_lock); 2650 } 2651 2652 if (error != 0 && error != EOWNERDEAD) { 2653 mtx_lock(&umtx_lock); 2654 uq->uq_inherited_pri = old_inherited_pri; 2655 pri = PRI_MAX; 2656 TAILQ_FOREACH(pi, &uq->uq_pi_contested, pi_link) { 2657 uq2 = TAILQ_FIRST(&pi->pi_blocked); 2658 if (uq2 != NULL) { 2659 if (pri > UPRI(uq2->uq_thread)) 2660 pri = UPRI(uq2->uq_thread); 2661 } 2662 } 2663 if (pri > uq->uq_inherited_pri) 2664 pri = uq->uq_inherited_pri; 2665 thread_lock(td); 2666 sched_lend_user_prio(td, pri); 2667 thread_unlock(td); 2668 mtx_unlock(&umtx_lock); 2669 } 2670 2671 out: 2672 umtxq_unbusy_unlocked(&uq->uq_key); 2673 umtx_key_release(&uq->uq_key); 2674 return (error); 2675 } 2676 2677 /* 2678 * Unlock a PP mutex. 2679 */ 2680 static int 2681 do_unlock_pp(struct thread *td, struct umutex *m, uint32_t flags, bool rb) 2682 { 2683 struct umtx_key key; 2684 struct umtx_q *uq, *uq2; 2685 struct umtx_pi *pi; 2686 uint32_t id, owner, rceiling; 2687 int error, pri, new_inherited_pri, su; 2688 2689 id = td->td_tid; 2690 uq = td->td_umtxq; 2691 su = (priv_check(td, PRIV_SCHED_RTPRIO) == 0); 2692 2693 /* 2694 * Make sure we own this mtx. 2695 */ 2696 error = fueword32(&m->m_owner, &owner); 2697 if (error == -1) 2698 return (EFAULT); 2699 2700 if ((owner & ~UMUTEX_CONTESTED) != id) 2701 return (EPERM); 2702 2703 error = copyin(&m->m_ceilings[1], &rceiling, sizeof(uint32_t)); 2704 if (error != 0) 2705 return (error); 2706 2707 if (rceiling == -1) 2708 new_inherited_pri = PRI_MAX; 2709 else { 2710 rceiling = RTP_PRIO_MAX - rceiling; 2711 if (rceiling > RTP_PRIO_MAX) 2712 return (EINVAL); 2713 new_inherited_pri = PRI_MIN_REALTIME + rceiling; 2714 } 2715 2716 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2717 TYPE_PP_ROBUST_UMUTEX : TYPE_PP_UMUTEX, GET_SHARE(flags), 2718 &key)) != 0) 2719 return (error); 2720 umtxq_lock(&key); 2721 umtxq_busy(&key); 2722 umtxq_unlock(&key); 2723 /* 2724 * For priority protected mutex, always set unlocked state 2725 * to UMUTEX_CONTESTED, so that userland always enters kernel 2726 * to lock the mutex, it is necessary because thread priority 2727 * has to be adjusted for such mutex. 2728 */ 2729 error = suword32(&m->m_owner, umtx_unlock_val(flags, rb) | 2730 UMUTEX_CONTESTED); 2731 2732 umtxq_lock(&key); 2733 if (error == 0) 2734 umtxq_signal(&key, 1); 2735 umtxq_unbusy(&key); 2736 umtxq_unlock(&key); 2737 2738 if (error == -1) 2739 error = EFAULT; 2740 else { 2741 mtx_lock(&umtx_lock); 2742 if (su != 0) 2743 uq->uq_inherited_pri = new_inherited_pri; 2744 pri = PRI_MAX; 2745 TAILQ_FOREACH(pi, &uq->uq_pi_contested, pi_link) { 2746 uq2 = TAILQ_FIRST(&pi->pi_blocked); 2747 if (uq2 != NULL) { 2748 if (pri > UPRI(uq2->uq_thread)) 2749 pri = UPRI(uq2->uq_thread); 2750 } 2751 } 2752 if (pri > uq->uq_inherited_pri) 2753 pri = uq->uq_inherited_pri; 2754 thread_lock(td); 2755 sched_lend_user_prio(td, pri); 2756 thread_unlock(td); 2757 mtx_unlock(&umtx_lock); 2758 } 2759 umtx_key_release(&key); 2760 return (error); 2761 } 2762 2763 static int 2764 do_set_ceiling(struct thread *td, struct umutex *m, uint32_t ceiling, 2765 uint32_t *old_ceiling) 2766 { 2767 struct umtx_q *uq; 2768 uint32_t flags, id, owner, save_ceiling; 2769 int error, rv, rv1; 2770 2771 error = fueword32(&m->m_flags, &flags); 2772 if (error == -1) 2773 return (EFAULT); 2774 if ((flags & UMUTEX_PRIO_PROTECT) == 0) 2775 return (EINVAL); 2776 if (ceiling > RTP_PRIO_MAX) 2777 return (EINVAL); 2778 id = td->td_tid; 2779 uq = td->td_umtxq; 2780 if ((error = umtx_key_get(m, (flags & UMUTEX_ROBUST) != 0 ? 2781 TYPE_PP_ROBUST_UMUTEX : TYPE_PP_UMUTEX, GET_SHARE(flags), 2782 &uq->uq_key)) != 0) 2783 return (error); 2784 for (;;) { 2785 umtxq_lock(&uq->uq_key); 2786 umtxq_busy(&uq->uq_key); 2787 umtxq_unlock(&uq->uq_key); 2788 2789 rv = fueword32(&m->m_ceilings[0], &save_ceiling); 2790 if (rv == -1) { 2791 error = EFAULT; 2792 break; 2793 } 2794 2795 rv = casueword32(&m->m_owner, UMUTEX_CONTESTED, &owner, 2796 id | UMUTEX_CONTESTED); 2797 if (rv == -1) { 2798 error = EFAULT; 2799 break; 2800 } 2801 2802 if (rv == 0) { 2803 MPASS(owner == UMUTEX_CONTESTED); 2804 rv = suword32(&m->m_ceilings[0], ceiling); 2805 rv1 = suword32(&m->m_owner, UMUTEX_CONTESTED); 2806 error = (rv == 0 && rv1 == 0) ? 0: EFAULT; 2807 break; 2808 } 2809 2810 if ((owner & ~UMUTEX_CONTESTED) == id) { 2811 rv = suword32(&m->m_ceilings[0], ceiling); 2812 error = rv == 0 ? 0 : EFAULT; 2813 break; 2814 } 2815 2816 if (owner == UMUTEX_RB_OWNERDEAD) { 2817 error = EOWNERDEAD; 2818 break; 2819 } else if (owner == UMUTEX_RB_NOTRECOV) { 2820 error = ENOTRECOVERABLE; 2821 break; 2822 } 2823 2824 /* 2825 * If we caught a signal, we have retried and now 2826 * exit immediately. 2827 */ 2828 if (error != 0) 2829 break; 2830 2831 /* 2832 * We set the contested bit, sleep. Otherwise the lock changed 2833 * and we need to retry or we lost a race to the thread 2834 * unlocking the umtx. 2835 */ 2836 umtxq_lock(&uq->uq_key); 2837 umtxq_insert(uq); 2838 umtxq_unbusy(&uq->uq_key); 2839 error = umtxq_sleep(uq, "umtxpp", NULL); 2840 umtxq_remove(uq); 2841 umtxq_unlock(&uq->uq_key); 2842 } 2843 umtxq_lock(&uq->uq_key); 2844 if (error == 0) 2845 umtxq_signal(&uq->uq_key, INT_MAX); 2846 umtxq_unbusy(&uq->uq_key); 2847 umtxq_unlock(&uq->uq_key); 2848 umtx_key_release(&uq->uq_key); 2849 if (error == 0 && old_ceiling != NULL) { 2850 rv = suword32(old_ceiling, save_ceiling); 2851 error = rv == 0 ? 0 : EFAULT; 2852 } 2853 return (error); 2854 } 2855 2856 /* 2857 * Lock a userland POSIX mutex. 2858 */ 2859 static int 2860 do_lock_umutex(struct thread *td, struct umutex *m, 2861 struct _umtx_time *timeout, int mode) 2862 { 2863 uint32_t flags; 2864 int error; 2865 2866 error = fueword32(&m->m_flags, &flags); 2867 if (error == -1) 2868 return (EFAULT); 2869 2870 switch (flags & (UMUTEX_PRIO_INHERIT | UMUTEX_PRIO_PROTECT)) { 2871 case 0: 2872 error = do_lock_normal(td, m, flags, timeout, mode); 2873 break; 2874 case UMUTEX_PRIO_INHERIT: 2875 error = do_lock_pi(td, m, flags, timeout, mode); 2876 break; 2877 case UMUTEX_PRIO_PROTECT: 2878 error = do_lock_pp(td, m, flags, timeout, mode); 2879 break; 2880 default: 2881 return (EINVAL); 2882 } 2883 if (timeout == NULL) { 2884 if (error == EINTR && mode != _UMUTEX_WAIT) 2885 error = ERESTART; 2886 } else { 2887 /* Timed-locking is not restarted. */ 2888 if (error == ERESTART) 2889 error = EINTR; 2890 } 2891 return (error); 2892 } 2893 2894 /* 2895 * Unlock a userland POSIX mutex. 2896 */ 2897 static int 2898 do_unlock_umutex(struct thread *td, struct umutex *m, bool rb) 2899 { 2900 uint32_t flags; 2901 int error; 2902 2903 error = fueword32(&m->m_flags, &flags); 2904 if (error == -1) 2905 return (EFAULT); 2906 2907 switch (flags & (UMUTEX_PRIO_INHERIT | UMUTEX_PRIO_PROTECT)) { 2908 case 0: 2909 return (do_unlock_normal(td, m, flags, rb)); 2910 case UMUTEX_PRIO_INHERIT: 2911 return (do_unlock_pi(td, m, flags, rb)); 2912 case UMUTEX_PRIO_PROTECT: 2913 return (do_unlock_pp(td, m, flags, rb)); 2914 } 2915 2916 return (EINVAL); 2917 } 2918 2919 static int 2920 do_cv_wait(struct thread *td, struct ucond *cv, struct umutex *m, 2921 struct timespec *timeout, u_long wflags) 2922 { 2923 struct umtx_abs_timeout timo; 2924 struct umtx_q *uq; 2925 uint32_t flags, clockid, hasw; 2926 int error; 2927 2928 uq = td->td_umtxq; 2929 error = fueword32(&cv->c_flags, &flags); 2930 if (error == -1) 2931 return (EFAULT); 2932 error = umtx_key_get(cv, TYPE_CV, GET_SHARE(flags), &uq->uq_key); 2933 if (error != 0) 2934 return (error); 2935 2936 if ((wflags & CVWAIT_CLOCKID) != 0) { 2937 error = fueword32(&cv->c_clockid, &clockid); 2938 if (error == -1) { 2939 umtx_key_release(&uq->uq_key); 2940 return (EFAULT); 2941 } 2942 if (clockid < CLOCK_REALTIME || 2943 clockid >= CLOCK_THREAD_CPUTIME_ID) { 2944 /* hmm, only HW clock id will work. */ 2945 umtx_key_release(&uq->uq_key); 2946 return (EINVAL); 2947 } 2948 } else { 2949 clockid = CLOCK_REALTIME; 2950 } 2951 2952 umtxq_lock(&uq->uq_key); 2953 umtxq_busy(&uq->uq_key); 2954 umtxq_insert(uq); 2955 umtxq_unlock(&uq->uq_key); 2956 2957 /* 2958 * Set c_has_waiters to 1 before releasing user mutex, also 2959 * don't modify cache line when unnecessary. 2960 */ 2961 error = fueword32(&cv->c_has_waiters, &hasw); 2962 if (error == 0 && hasw == 0) 2963 error = suword32(&cv->c_has_waiters, 1); 2964 if (error != 0) { 2965 umtxq_lock(&uq->uq_key); 2966 umtxq_remove(uq); 2967 umtxq_unbusy(&uq->uq_key); 2968 error = EFAULT; 2969 goto out; 2970 } 2971 2972 umtxq_unbusy_unlocked(&uq->uq_key); 2973 2974 error = do_unlock_umutex(td, m, false); 2975 2976 if (timeout != NULL) 2977 umtx_abs_timeout_init(&timo, clockid, 2978 (wflags & CVWAIT_ABSTIME) != 0, timeout); 2979 2980 umtxq_lock(&uq->uq_key); 2981 if (error == 0) { 2982 error = umtxq_sleep(uq, "ucond", timeout == NULL ? 2983 NULL : &timo); 2984 } 2985 2986 if ((uq->uq_flags & UQF_UMTXQ) == 0) 2987 error = 0; 2988 else { 2989 /* 2990 * This must be timeout,interrupted by signal or 2991 * surprious wakeup, clear c_has_waiter flag when 2992 * necessary. 2993 */ 2994 umtxq_busy(&uq->uq_key); 2995 if ((uq->uq_flags & UQF_UMTXQ) != 0) { 2996 int oldlen = uq->uq_cur_queue->length; 2997 umtxq_remove(uq); 2998 if (oldlen == 1) { 2999 umtxq_unlock(&uq->uq_key); 3000 if (suword32(&cv->c_has_waiters, 0) != 0 && 3001 error == 0) 3002 error = EFAULT; 3003 umtxq_lock(&uq->uq_key); 3004 } 3005 } 3006 umtxq_unbusy(&uq->uq_key); 3007 if (error == ERESTART) 3008 error = EINTR; 3009 } 3010 out: 3011 umtxq_unlock(&uq->uq_key); 3012 umtx_key_release(&uq->uq_key); 3013 return (error); 3014 } 3015 3016 /* 3017 * Signal a userland condition variable. 3018 */ 3019 static int 3020 do_cv_signal(struct thread *td, struct ucond *cv) 3021 { 3022 struct umtx_key key; 3023 int error, cnt, nwake; 3024 uint32_t flags; 3025 3026 error = fueword32(&cv->c_flags, &flags); 3027 if (error == -1) 3028 return (EFAULT); 3029 if ((error = umtx_key_get(cv, TYPE_CV, GET_SHARE(flags), &key)) != 0) 3030 return (error); 3031 umtxq_lock(&key); 3032 umtxq_busy(&key); 3033 cnt = umtxq_count(&key); 3034 nwake = umtxq_signal(&key, 1); 3035 if (cnt <= nwake) { 3036 umtxq_unlock(&key); 3037 error = suword32(&cv->c_has_waiters, 0); 3038 if (error == -1) 3039 error = EFAULT; 3040 umtxq_lock(&key); 3041 } 3042 umtxq_unbusy(&key); 3043 umtxq_unlock(&key); 3044 umtx_key_release(&key); 3045 return (error); 3046 } 3047 3048 static int 3049 do_cv_broadcast(struct thread *td, struct ucond *cv) 3050 { 3051 struct umtx_key key; 3052 int error; 3053 uint32_t flags; 3054 3055 error = fueword32(&cv->c_flags, &flags); 3056 if (error == -1) 3057 return (EFAULT); 3058 if ((error = umtx_key_get(cv, TYPE_CV, GET_SHARE(flags), &key)) != 0) 3059 return (error); 3060 3061 umtxq_lock(&key); 3062 umtxq_busy(&key); 3063 umtxq_signal(&key, INT_MAX); 3064 umtxq_unlock(&key); 3065 3066 error = suword32(&cv->c_has_waiters, 0); 3067 if (error == -1) 3068 error = EFAULT; 3069 3070 umtxq_unbusy_unlocked(&key); 3071 3072 umtx_key_release(&key); 3073 return (error); 3074 } 3075 3076 static int 3077 do_rw_rdlock(struct thread *td, struct urwlock *rwlock, long fflag, 3078 struct _umtx_time *timeout) 3079 { 3080 struct umtx_abs_timeout timo; 3081 struct umtx_q *uq; 3082 uint32_t flags, wrflags; 3083 int32_t state, oldstate; 3084 int32_t blocked_readers; 3085 int error, error1, rv; 3086 3087 uq = td->td_umtxq; 3088 error = fueword32(&rwlock->rw_flags, &flags); 3089 if (error == -1) 3090 return (EFAULT); 3091 error = umtx_key_get(rwlock, TYPE_RWLOCK, GET_SHARE(flags), &uq->uq_key); 3092 if (error != 0) 3093 return (error); 3094 3095 if (timeout != NULL) 3096 umtx_abs_timeout_init2(&timo, timeout); 3097 3098 wrflags = URWLOCK_WRITE_OWNER; 3099 if (!(fflag & URWLOCK_PREFER_READER) && !(flags & URWLOCK_PREFER_READER)) 3100 wrflags |= URWLOCK_WRITE_WAITERS; 3101 3102 for (;;) { 3103 rv = fueword32(&rwlock->rw_state, &state); 3104 if (rv == -1) { 3105 umtx_key_release(&uq->uq_key); 3106 return (EFAULT); 3107 } 3108 3109 /* try to lock it */ 3110 while (!(state & wrflags)) { 3111 if (__predict_false(URWLOCK_READER_COUNT(state) == 3112 URWLOCK_MAX_READERS)) { 3113 umtx_key_release(&uq->uq_key); 3114 return (EAGAIN); 3115 } 3116 rv = casueword32(&rwlock->rw_state, state, 3117 &oldstate, state + 1); 3118 if (rv == -1) { 3119 umtx_key_release(&uq->uq_key); 3120 return (EFAULT); 3121 } 3122 if (rv == 0) { 3123 MPASS(oldstate == state); 3124 umtx_key_release(&uq->uq_key); 3125 return (0); 3126 } 3127 error = thread_check_susp(td, true); 3128 if (error != 0) 3129 break; 3130 state = oldstate; 3131 } 3132 3133 if (error) 3134 break; 3135 3136 /* grab monitor lock */ 3137 umtxq_lock(&uq->uq_key); 3138 umtxq_busy(&uq->uq_key); 3139 umtxq_unlock(&uq->uq_key); 3140 3141 /* 3142 * re-read the state, in case it changed between the try-lock above 3143 * and the check below 3144 */ 3145 rv = fueword32(&rwlock->rw_state, &state); 3146 if (rv == -1) 3147 error = EFAULT; 3148 3149 /* set read contention bit */ 3150 while (error == 0 && (state & wrflags) && 3151 !(state & URWLOCK_READ_WAITERS)) { 3152 rv = casueword32(&rwlock->rw_state, state, 3153 &oldstate, state | URWLOCK_READ_WAITERS); 3154 if (rv == -1) { 3155 error = EFAULT; 3156 break; 3157 } 3158 if (rv == 0) { 3159 MPASS(oldstate == state); 3160 goto sleep; 3161 } 3162 state = oldstate; 3163 error = thread_check_susp(td, false); 3164 if (error != 0) 3165 break; 3166 } 3167 if (error != 0) { 3168 umtxq_unbusy_unlocked(&uq->uq_key); 3169 break; 3170 } 3171 3172 /* state is changed while setting flags, restart */ 3173 if (!(state & wrflags)) { 3174 umtxq_unbusy_unlocked(&uq->uq_key); 3175 error = thread_check_susp(td, true); 3176 if (error != 0) 3177 break; 3178 continue; 3179 } 3180 3181 sleep: 3182 /* 3183 * Contention bit is set, before sleeping, increase 3184 * read waiter count. 3185 */ 3186 rv = fueword32(&rwlock->rw_blocked_readers, 3187 &blocked_readers); 3188 if (rv == 0) 3189 rv = suword32(&rwlock->rw_blocked_readers, 3190 blocked_readers + 1); 3191 if (rv == -1) { 3192 umtxq_unbusy_unlocked(&uq->uq_key); 3193 error = EFAULT; 3194 break; 3195 } 3196 3197 while (state & wrflags) { 3198 umtxq_lock(&uq->uq_key); 3199 umtxq_insert(uq); 3200 umtxq_unbusy(&uq->uq_key); 3201 3202 error = umtxq_sleep(uq, "urdlck", timeout == NULL ? 3203 NULL : &timo); 3204 3205 umtxq_busy(&uq->uq_key); 3206 umtxq_remove(uq); 3207 umtxq_unlock(&uq->uq_key); 3208 if (error) 3209 break; 3210 rv = fueword32(&rwlock->rw_state, &state); 3211 if (rv == -1) { 3212 error = EFAULT; 3213 break; 3214 } 3215 } 3216 3217 /* decrease read waiter count, and may clear read contention bit */ 3218 rv = fueword32(&rwlock->rw_blocked_readers, 3219 &blocked_readers); 3220 if (rv == 0) 3221 rv = suword32(&rwlock->rw_blocked_readers, 3222 blocked_readers - 1); 3223 if (rv == -1) { 3224 umtxq_unbusy_unlocked(&uq->uq_key); 3225 error = EFAULT; 3226 break; 3227 } 3228 if (blocked_readers == 1) { 3229 rv = fueword32(&rwlock->rw_state, &state); 3230 if (rv == -1) { 3231 umtxq_unbusy_unlocked(&uq->uq_key); 3232 error = EFAULT; 3233 break; 3234 } 3235 for (;;) { 3236 rv = casueword32(&rwlock->rw_state, state, 3237 &oldstate, state & ~URWLOCK_READ_WAITERS); 3238 if (rv == -1) { 3239 error = EFAULT; 3240 break; 3241 } 3242 if (rv == 0) { 3243 MPASS(oldstate == state); 3244 break; 3245 } 3246 state = oldstate; 3247 error1 = thread_check_susp(td, false); 3248 if (error1 != 0) { 3249 if (error == 0) 3250 error = error1; 3251 break; 3252 } 3253 } 3254 } 3255 3256 umtxq_unbusy_unlocked(&uq->uq_key); 3257 if (error != 0) 3258 break; 3259 } 3260 umtx_key_release(&uq->uq_key); 3261 if (error == ERESTART) 3262 error = EINTR; 3263 return (error); 3264 } 3265 3266 static int 3267 do_rw_wrlock(struct thread *td, struct urwlock *rwlock, struct _umtx_time *timeout) 3268 { 3269 struct umtx_abs_timeout timo; 3270 struct umtx_q *uq; 3271 uint32_t flags; 3272 int32_t state, oldstate; 3273 int32_t blocked_writers; 3274 int32_t blocked_readers; 3275 int error, error1, rv; 3276 3277 uq = td->td_umtxq; 3278 error = fueword32(&rwlock->rw_flags, &flags); 3279 if (error == -1) 3280 return (EFAULT); 3281 error = umtx_key_get(rwlock, TYPE_RWLOCK, GET_SHARE(flags), &uq->uq_key); 3282 if (error != 0) 3283 return (error); 3284 3285 if (timeout != NULL) 3286 umtx_abs_timeout_init2(&timo, timeout); 3287 3288 blocked_readers = 0; 3289 for (;;) { 3290 rv = fueword32(&rwlock->rw_state, &state); 3291 if (rv == -1) { 3292 umtx_key_release(&uq->uq_key); 3293 return (EFAULT); 3294 } 3295 while ((state & URWLOCK_WRITE_OWNER) == 0 && 3296 URWLOCK_READER_COUNT(state) == 0) { 3297 rv = casueword32(&rwlock->rw_state, state, 3298 &oldstate, state | URWLOCK_WRITE_OWNER); 3299 if (rv == -1) { 3300 umtx_key_release(&uq->uq_key); 3301 return (EFAULT); 3302 } 3303 if (rv == 0) { 3304 MPASS(oldstate == state); 3305 umtx_key_release(&uq->uq_key); 3306 return (0); 3307 } 3308 state = oldstate; 3309 error = thread_check_susp(td, true); 3310 if (error != 0) 3311 break; 3312 } 3313 3314 if (error) { 3315 if ((state & (URWLOCK_WRITE_OWNER | 3316 URWLOCK_WRITE_WAITERS)) == 0 && 3317 blocked_readers != 0) { 3318 umtxq_lock(&uq->uq_key); 3319 umtxq_busy(&uq->uq_key); 3320 umtxq_signal_queue(&uq->uq_key, INT_MAX, 3321 UMTX_SHARED_QUEUE); 3322 umtxq_unbusy(&uq->uq_key); 3323 umtxq_unlock(&uq->uq_key); 3324 } 3325 3326 break; 3327 } 3328 3329 /* grab monitor lock */ 3330 umtxq_lock(&uq->uq_key); 3331 umtxq_busy(&uq->uq_key); 3332 umtxq_unlock(&uq->uq_key); 3333 3334 /* 3335 * Re-read the state, in case it changed between the 3336 * try-lock above and the check below. 3337 */ 3338 rv = fueword32(&rwlock->rw_state, &state); 3339 if (rv == -1) 3340 error = EFAULT; 3341 3342 while (error == 0 && ((state & URWLOCK_WRITE_OWNER) || 3343 URWLOCK_READER_COUNT(state) != 0) && 3344 (state & URWLOCK_WRITE_WAITERS) == 0) { 3345 rv = casueword32(&rwlock->rw_state, state, 3346 &oldstate, state | URWLOCK_WRITE_WAITERS); 3347 if (rv == -1) { 3348 error = EFAULT; 3349 break; 3350 } 3351 if (rv == 0) { 3352 MPASS(oldstate == state); 3353 goto sleep; 3354 } 3355 state = oldstate; 3356 error = thread_check_susp(td, false); 3357 if (error != 0) 3358 break; 3359 } 3360 if (error != 0) { 3361 umtxq_unbusy_unlocked(&uq->uq_key); 3362 break; 3363 } 3364 3365 if ((state & URWLOCK_WRITE_OWNER) == 0 && 3366 URWLOCK_READER_COUNT(state) == 0) { 3367 umtxq_unbusy_unlocked(&uq->uq_key); 3368 error = thread_check_susp(td, false); 3369 if (error != 0) 3370 break; 3371 continue; 3372 } 3373 sleep: 3374 rv = fueword32(&rwlock->rw_blocked_writers, 3375 &blocked_writers); 3376 if (rv == 0) 3377 rv = suword32(&rwlock->rw_blocked_writers, 3378 blocked_writers + 1); 3379 if (rv == -1) { 3380 umtxq_unbusy_unlocked(&uq->uq_key); 3381 error = EFAULT; 3382 break; 3383 } 3384 3385 while ((state & URWLOCK_WRITE_OWNER) || 3386 URWLOCK_READER_COUNT(state) != 0) { 3387 umtxq_lock(&uq->uq_key); 3388 umtxq_insert_queue(uq, UMTX_EXCLUSIVE_QUEUE); 3389 umtxq_unbusy(&uq->uq_key); 3390 3391 error = umtxq_sleep(uq, "uwrlck", timeout == NULL ? 3392 NULL : &timo); 3393 3394 umtxq_busy(&uq->uq_key); 3395 umtxq_remove_queue(uq, UMTX_EXCLUSIVE_QUEUE); 3396 umtxq_unlock(&uq->uq_key); 3397 if (error) 3398 break; 3399 rv = fueword32(&rwlock->rw_state, &state); 3400 if (rv == -1) { 3401 error = EFAULT; 3402 break; 3403 } 3404 } 3405 3406 rv = fueword32(&rwlock->rw_blocked_writers, 3407 &blocked_writers); 3408 if (rv == 0) 3409 rv = suword32(&rwlock->rw_blocked_writers, 3410 blocked_writers - 1); 3411 if (rv == -1) { 3412 umtxq_unbusy_unlocked(&uq->uq_key); 3413 error = EFAULT; 3414 break; 3415 } 3416 if (blocked_writers == 1) { 3417 rv = fueword32(&rwlock->rw_state, &state); 3418 if (rv == -1) { 3419 umtxq_unbusy_unlocked(&uq->uq_key); 3420 error = EFAULT; 3421 break; 3422 } 3423 for (;;) { 3424 rv = casueword32(&rwlock->rw_state, state, 3425 &oldstate, state & ~URWLOCK_WRITE_WAITERS); 3426 if (rv == -1) { 3427 error = EFAULT; 3428 break; 3429 } 3430 if (rv == 0) { 3431 MPASS(oldstate == state); 3432 break; 3433 } 3434 state = oldstate; 3435 error1 = thread_check_susp(td, false); 3436 /* 3437 * We are leaving the URWLOCK_WRITE_WAITERS 3438 * behind, but this should not harm the 3439 * correctness. 3440 */ 3441 if (error1 != 0) { 3442 if (error == 0) 3443 error = error1; 3444 break; 3445 } 3446 } 3447 rv = fueword32(&rwlock->rw_blocked_readers, 3448 &blocked_readers); 3449 if (rv == -1) { 3450 umtxq_unbusy_unlocked(&uq->uq_key); 3451 error = EFAULT; 3452 break; 3453 } 3454 } else 3455 blocked_readers = 0; 3456 3457 umtxq_unbusy_unlocked(&uq->uq_key); 3458 } 3459 3460 umtx_key_release(&uq->uq_key); 3461 if (error == ERESTART) 3462 error = EINTR; 3463 return (error); 3464 } 3465 3466 static int 3467 do_rw_unlock(struct thread *td, struct urwlock *rwlock) 3468 { 3469 struct umtx_q *uq; 3470 uint32_t flags; 3471 int32_t state, oldstate; 3472 int error, rv, q, count; 3473 3474 uq = td->td_umtxq; 3475 error = fueword32(&rwlock->rw_flags, &flags); 3476 if (error == -1) 3477 return (EFAULT); 3478 error = umtx_key_get(rwlock, TYPE_RWLOCK, GET_SHARE(flags), &uq->uq_key); 3479 if (error != 0) 3480 return (error); 3481 3482 error = fueword32(&rwlock->rw_state, &state); 3483 if (error == -1) { 3484 error = EFAULT; 3485 goto out; 3486 } 3487 if (state & URWLOCK_WRITE_OWNER) { 3488 for (;;) { 3489 rv = casueword32(&rwlock->rw_state, state, 3490 &oldstate, state & ~URWLOCK_WRITE_OWNER); 3491 if (rv == -1) { 3492 error = EFAULT; 3493 goto out; 3494 } 3495 if (rv == 1) { 3496 state = oldstate; 3497 if (!(oldstate & URWLOCK_WRITE_OWNER)) { 3498 error = EPERM; 3499 goto out; 3500 } 3501 error = thread_check_susp(td, true); 3502 if (error != 0) 3503 goto out; 3504 } else 3505 break; 3506 } 3507 } else if (URWLOCK_READER_COUNT(state) != 0) { 3508 for (;;) { 3509 rv = casueword32(&rwlock->rw_state, state, 3510 &oldstate, state - 1); 3511 if (rv == -1) { 3512 error = EFAULT; 3513 goto out; 3514 } 3515 if (rv == 1) { 3516 state = oldstate; 3517 if (URWLOCK_READER_COUNT(oldstate) == 0) { 3518 error = EPERM; 3519 goto out; 3520 } 3521 error = thread_check_susp(td, true); 3522 if (error != 0) 3523 goto out; 3524 } else 3525 break; 3526 } 3527 } else { 3528 error = EPERM; 3529 goto out; 3530 } 3531 3532 count = 0; 3533 3534 if (!(flags & URWLOCK_PREFER_READER)) { 3535 if (state & URWLOCK_WRITE_WAITERS) { 3536 count = 1; 3537 q = UMTX_EXCLUSIVE_QUEUE; 3538 } else if (state & URWLOCK_READ_WAITERS) { 3539 count = INT_MAX; 3540 q = UMTX_SHARED_QUEUE; 3541 } 3542 } else { 3543 if (state & URWLOCK_READ_WAITERS) { 3544 count = INT_MAX; 3545 q = UMTX_SHARED_QUEUE; 3546 } else if (state & URWLOCK_WRITE_WAITERS) { 3547 count = 1; 3548 q = UMTX_EXCLUSIVE_QUEUE; 3549 } 3550 } 3551 3552 if (count) { 3553 umtxq_lock(&uq->uq_key); 3554 umtxq_busy(&uq->uq_key); 3555 umtxq_signal_queue(&uq->uq_key, count, q); 3556 umtxq_unbusy(&uq->uq_key); 3557 umtxq_unlock(&uq->uq_key); 3558 } 3559 out: 3560 umtx_key_release(&uq->uq_key); 3561 return (error); 3562 } 3563 3564 #if defined(COMPAT_FREEBSD9) || defined(COMPAT_FREEBSD10) 3565 static int 3566 do_sem_wait(struct thread *td, struct _usem *sem, struct _umtx_time *timeout) 3567 { 3568 struct umtx_abs_timeout timo; 3569 struct umtx_q *uq; 3570 uint32_t flags, count, count1; 3571 int error, rv, rv1; 3572 3573 uq = td->td_umtxq; 3574 error = fueword32(&sem->_flags, &flags); 3575 if (error == -1) 3576 return (EFAULT); 3577 error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &uq->uq_key); 3578 if (error != 0) 3579 return (error); 3580 3581 if (timeout != NULL) 3582 umtx_abs_timeout_init2(&timo, timeout); 3583 3584 again: 3585 umtxq_lock(&uq->uq_key); 3586 umtxq_busy(&uq->uq_key); 3587 umtxq_insert(uq); 3588 umtxq_unlock(&uq->uq_key); 3589 rv = casueword32(&sem->_has_waiters, 0, &count1, 1); 3590 if (rv != -1) 3591 rv1 = fueword32(&sem->_count, &count); 3592 if (rv == -1 || rv1 == -1 || count != 0 || (rv == 1 && count1 == 0)) { 3593 if (rv == 0) 3594 rv = suword32(&sem->_has_waiters, 0); 3595 umtxq_lock(&uq->uq_key); 3596 umtxq_unbusy(&uq->uq_key); 3597 umtxq_remove(uq); 3598 umtxq_unlock(&uq->uq_key); 3599 if (rv == -1 || rv1 == -1) { 3600 error = EFAULT; 3601 goto out; 3602 } 3603 if (count != 0) { 3604 error = 0; 3605 goto out; 3606 } 3607 MPASS(rv == 1 && count1 == 0); 3608 rv = thread_check_susp(td, true); 3609 if (rv == 0) 3610 goto again; 3611 error = rv; 3612 goto out; 3613 } 3614 umtxq_lock(&uq->uq_key); 3615 umtxq_unbusy(&uq->uq_key); 3616 3617 error = umtxq_sleep(uq, "usem", timeout == NULL ? NULL : &timo); 3618 3619 if ((uq->uq_flags & UQF_UMTXQ) == 0) 3620 error = 0; 3621 else { 3622 umtxq_remove(uq); 3623 /* A relative timeout cannot be restarted. */ 3624 if (error == ERESTART && timeout != NULL && 3625 (timeout->_flags & UMTX_ABSTIME) == 0) 3626 error = EINTR; 3627 } 3628 umtxq_unlock(&uq->uq_key); 3629 out: 3630 umtx_key_release(&uq->uq_key); 3631 return (error); 3632 } 3633 3634 /* 3635 * Signal a userland semaphore. 3636 */ 3637 static int 3638 do_sem_wake(struct thread *td, struct _usem *sem) 3639 { 3640 struct umtx_key key; 3641 int error, cnt; 3642 uint32_t flags; 3643 3644 error = fueword32(&sem->_flags, &flags); 3645 if (error == -1) 3646 return (EFAULT); 3647 if ((error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &key)) != 0) 3648 return (error); 3649 umtxq_lock(&key); 3650 umtxq_busy(&key); 3651 cnt = umtxq_count(&key); 3652 if (cnt > 0) { 3653 /* 3654 * Check if count is greater than 0, this means the memory is 3655 * still being referenced by user code, so we can safely 3656 * update _has_waiters flag. 3657 */ 3658 if (cnt == 1) { 3659 umtxq_unlock(&key); 3660 error = suword32(&sem->_has_waiters, 0); 3661 umtxq_lock(&key); 3662 if (error == -1) 3663 error = EFAULT; 3664 } 3665 umtxq_signal(&key, 1); 3666 } 3667 umtxq_unbusy(&key); 3668 umtxq_unlock(&key); 3669 umtx_key_release(&key); 3670 return (error); 3671 } 3672 #endif 3673 3674 static int 3675 do_sem2_wait(struct thread *td, struct _usem2 *sem, struct _umtx_time *timeout) 3676 { 3677 struct umtx_abs_timeout timo; 3678 struct umtx_q *uq; 3679 uint32_t count, flags; 3680 int error, rv; 3681 3682 uq = td->td_umtxq; 3683 flags = fuword32(&sem->_flags); 3684 if (timeout != NULL) 3685 umtx_abs_timeout_init2(&timo, timeout); 3686 3687 again: 3688 error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &uq->uq_key); 3689 if (error != 0) 3690 return (error); 3691 umtxq_lock(&uq->uq_key); 3692 umtxq_busy(&uq->uq_key); 3693 umtxq_insert(uq); 3694 umtxq_unlock(&uq->uq_key); 3695 rv = fueword32(&sem->_count, &count); 3696 if (rv == -1) { 3697 umtxq_lock(&uq->uq_key); 3698 umtxq_unbusy(&uq->uq_key); 3699 umtxq_remove(uq); 3700 umtxq_unlock(&uq->uq_key); 3701 umtx_key_release(&uq->uq_key); 3702 return (EFAULT); 3703 } 3704 for (;;) { 3705 if (USEM_COUNT(count) != 0) { 3706 umtxq_lock(&uq->uq_key); 3707 umtxq_unbusy(&uq->uq_key); 3708 umtxq_remove(uq); 3709 umtxq_unlock(&uq->uq_key); 3710 umtx_key_release(&uq->uq_key); 3711 return (0); 3712 } 3713 if (count == USEM_HAS_WAITERS) 3714 break; 3715 rv = casueword32(&sem->_count, 0, &count, USEM_HAS_WAITERS); 3716 if (rv == 0) 3717 break; 3718 umtxq_lock(&uq->uq_key); 3719 umtxq_unbusy(&uq->uq_key); 3720 umtxq_remove(uq); 3721 umtxq_unlock(&uq->uq_key); 3722 umtx_key_release(&uq->uq_key); 3723 if (rv == -1) 3724 return (EFAULT); 3725 rv = thread_check_susp(td, true); 3726 if (rv != 0) 3727 return (rv); 3728 goto again; 3729 } 3730 umtxq_lock(&uq->uq_key); 3731 umtxq_unbusy(&uq->uq_key); 3732 3733 error = umtxq_sleep(uq, "usem", timeout == NULL ? NULL : &timo); 3734 3735 if ((uq->uq_flags & UQF_UMTXQ) == 0) 3736 error = 0; 3737 else { 3738 umtxq_remove(uq); 3739 if (timeout != NULL && (timeout->_flags & UMTX_ABSTIME) == 0) { 3740 /* A relative timeout cannot be restarted. */ 3741 if (error == ERESTART) 3742 error = EINTR; 3743 if (error == EINTR) { 3744 kern_clock_gettime(curthread, timo.clockid, 3745 &timo.cur); 3746 timespecsub(&timo.end, &timo.cur, 3747 &timeout->_timeout); 3748 } 3749 } 3750 } 3751 umtxq_unlock(&uq->uq_key); 3752 umtx_key_release(&uq->uq_key); 3753 return (error); 3754 } 3755 3756 /* 3757 * Signal a userland semaphore. 3758 */ 3759 static int 3760 do_sem2_wake(struct thread *td, struct _usem2 *sem) 3761 { 3762 struct umtx_key key; 3763 int error, cnt, rv; 3764 uint32_t count, flags; 3765 3766 rv = fueword32(&sem->_flags, &flags); 3767 if (rv == -1) 3768 return (EFAULT); 3769 if ((error = umtx_key_get(sem, TYPE_SEM, GET_SHARE(flags), &key)) != 0) 3770 return (error); 3771 umtxq_lock(&key); 3772 umtxq_busy(&key); 3773 cnt = umtxq_count(&key); 3774 if (cnt > 0) { 3775 /* 3776 * If this was the last sleeping thread, clear the waiters 3777 * flag in _count. 3778 */ 3779 if (cnt == 1) { 3780 umtxq_unlock(&key); 3781 rv = fueword32(&sem->_count, &count); 3782 while (rv != -1 && count & USEM_HAS_WAITERS) { 3783 rv = casueword32(&sem->_count, count, &count, 3784 count & ~USEM_HAS_WAITERS); 3785 if (rv == 1) { 3786 rv = thread_check_susp(td, true); 3787 if (rv != 0) 3788 break; 3789 } 3790 } 3791 if (rv == -1) 3792 error = EFAULT; 3793 else if (rv > 0) { 3794 error = rv; 3795 } 3796 umtxq_lock(&key); 3797 } 3798 3799 umtxq_signal(&key, 1); 3800 } 3801 umtxq_unbusy(&key); 3802 umtxq_unlock(&key); 3803 umtx_key_release(&key); 3804 return (error); 3805 } 3806 3807 #ifdef COMPAT_FREEBSD10 3808 int 3809 freebsd10__umtx_lock(struct thread *td, struct freebsd10__umtx_lock_args *uap) 3810 { 3811 return (do_lock_umtx(td, uap->umtx, td->td_tid, 0)); 3812 } 3813 3814 int 3815 freebsd10__umtx_unlock(struct thread *td, 3816 struct freebsd10__umtx_unlock_args *uap) 3817 { 3818 return (do_unlock_umtx(td, uap->umtx, td->td_tid)); 3819 } 3820 #endif 3821 3822 inline int 3823 umtx_copyin_timeout(const void *uaddr, struct timespec *tsp) 3824 { 3825 int error; 3826 3827 error = copyin(uaddr, tsp, sizeof(*tsp)); 3828 if (error == 0) { 3829 if (!timespecvalid_interval(tsp)) 3830 error = EINVAL; 3831 } 3832 return (error); 3833 } 3834 3835 static inline int 3836 umtx_copyin_umtx_time(const void *uaddr, size_t size, struct _umtx_time *tp) 3837 { 3838 int error; 3839 3840 if (size <= sizeof(tp->_timeout)) { 3841 tp->_clockid = CLOCK_REALTIME; 3842 tp->_flags = 0; 3843 error = copyin(uaddr, &tp->_timeout, sizeof(tp->_timeout)); 3844 } else 3845 error = copyin(uaddr, tp, sizeof(*tp)); 3846 if (error != 0) 3847 return (error); 3848 if (!timespecvalid_interval(&tp->_timeout)) 3849 return (EINVAL); 3850 return (0); 3851 } 3852 3853 static int 3854 umtx_copyin_robust_lists(const void *uaddr, size_t size, 3855 struct umtx_robust_lists_params *rb) 3856 { 3857 3858 if (size > sizeof(*rb)) 3859 return (EINVAL); 3860 return (copyin(uaddr, rb, size)); 3861 } 3862 3863 static int 3864 umtx_copyout_timeout(void *uaddr, size_t sz, struct timespec *tsp) 3865 { 3866 3867 /* 3868 * Should be guaranteed by the caller, sz == uaddr1 - sizeof(_umtx_time) 3869 * and we're only called if sz >= sizeof(timespec) as supplied in the 3870 * copyops. 3871 */ 3872 KASSERT(sz >= sizeof(*tsp), 3873 ("umtx_copyops specifies incorrect sizes")); 3874 3875 return (copyout(tsp, uaddr, sizeof(*tsp))); 3876 } 3877 3878 #ifdef COMPAT_FREEBSD10 3879 static int 3880 __umtx_op_lock_umtx(struct thread *td, struct _umtx_op_args *uap, 3881 const struct umtx_copyops *ops) 3882 { 3883 struct timespec *ts, timeout; 3884 int error; 3885 3886 /* Allow a null timespec (wait forever). */ 3887 if (uap->uaddr2 == NULL) 3888 ts = NULL; 3889 else { 3890 error = ops->copyin_timeout(uap->uaddr2, &timeout); 3891 if (error != 0) 3892 return (error); 3893 ts = &timeout; 3894 } 3895 #ifdef COMPAT_FREEBSD32 3896 if (ops->compat32) 3897 return (do_lock_umtx32(td, uap->obj, uap->val, ts)); 3898 #endif 3899 return (do_lock_umtx(td, uap->obj, uap->val, ts)); 3900 } 3901 3902 static int 3903 __umtx_op_unlock_umtx(struct thread *td, struct _umtx_op_args *uap, 3904 const struct umtx_copyops *ops) 3905 { 3906 #ifdef COMPAT_FREEBSD32 3907 if (ops->compat32) 3908 return (do_unlock_umtx32(td, uap->obj, uap->val)); 3909 #endif 3910 return (do_unlock_umtx(td, uap->obj, uap->val)); 3911 } 3912 #endif /* COMPAT_FREEBSD10 */ 3913 3914 #if !defined(COMPAT_FREEBSD10) 3915 static int 3916 __umtx_op_unimpl(struct thread *td __unused, struct _umtx_op_args *uap __unused, 3917 const struct umtx_copyops *ops __unused) 3918 { 3919 return (EOPNOTSUPP); 3920 } 3921 #endif /* COMPAT_FREEBSD10 */ 3922 3923 static int 3924 __umtx_op_wait(struct thread *td, struct _umtx_op_args *uap, 3925 const struct umtx_copyops *ops) 3926 { 3927 struct _umtx_time timeout, *tm_p; 3928 int error; 3929 3930 if (uap->uaddr2 == NULL) 3931 tm_p = NULL; 3932 else { 3933 error = ops->copyin_umtx_time( 3934 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 3935 if (error != 0) 3936 return (error); 3937 tm_p = &timeout; 3938 } 3939 return (do_wait(td, uap->obj, uap->val, tm_p, ops->compat32, 0)); 3940 } 3941 3942 static int 3943 __umtx_op_wait_uint(struct thread *td, struct _umtx_op_args *uap, 3944 const struct umtx_copyops *ops) 3945 { 3946 struct _umtx_time timeout, *tm_p; 3947 int error; 3948 3949 if (uap->uaddr2 == NULL) 3950 tm_p = NULL; 3951 else { 3952 error = ops->copyin_umtx_time( 3953 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 3954 if (error != 0) 3955 return (error); 3956 tm_p = &timeout; 3957 } 3958 return (do_wait(td, uap->obj, uap->val, tm_p, 1, 0)); 3959 } 3960 3961 static int 3962 __umtx_op_wait_uint_private(struct thread *td, struct _umtx_op_args *uap, 3963 const struct umtx_copyops *ops) 3964 { 3965 struct _umtx_time *tm_p, timeout; 3966 int error; 3967 3968 if (uap->uaddr2 == NULL) 3969 tm_p = NULL; 3970 else { 3971 error = ops->copyin_umtx_time( 3972 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 3973 if (error != 0) 3974 return (error); 3975 tm_p = &timeout; 3976 } 3977 return (do_wait(td, uap->obj, uap->val, tm_p, 1, 1)); 3978 } 3979 3980 static int 3981 __umtx_op_wake(struct thread *td, struct _umtx_op_args *uap, 3982 const struct umtx_copyops *ops __unused) 3983 { 3984 3985 return (kern_umtx_wake(td, uap->obj, uap->val, 0)); 3986 } 3987 3988 #define BATCH_SIZE 128 3989 static int 3990 __umtx_op_nwake_private_native(struct thread *td, struct _umtx_op_args *uap) 3991 { 3992 char *uaddrs[BATCH_SIZE], **upp; 3993 int count, error, i, pos, tocopy; 3994 3995 upp = (char **)uap->obj; 3996 error = 0; 3997 for (count = uap->val, pos = 0; count > 0; count -= tocopy, 3998 pos += tocopy) { 3999 tocopy = MIN(count, BATCH_SIZE); 4000 error = copyin(upp + pos, uaddrs, tocopy * sizeof(char *)); 4001 if (error != 0) 4002 break; 4003 for (i = 0; i < tocopy; ++i) { 4004 kern_umtx_wake(td, uaddrs[i], INT_MAX, 1); 4005 } 4006 maybe_yield(); 4007 } 4008 return (error); 4009 } 4010 4011 static int 4012 __umtx_op_nwake_private_compat32(struct thread *td, struct _umtx_op_args *uap) 4013 { 4014 uint32_t uaddrs[BATCH_SIZE], *upp; 4015 int count, error, i, pos, tocopy; 4016 4017 upp = (uint32_t *)uap->obj; 4018 error = 0; 4019 for (count = uap->val, pos = 0; count > 0; count -= tocopy, 4020 pos += tocopy) { 4021 tocopy = MIN(count, BATCH_SIZE); 4022 error = copyin(upp + pos, uaddrs, tocopy * sizeof(uint32_t)); 4023 if (error != 0) 4024 break; 4025 for (i = 0; i < tocopy; ++i) { 4026 kern_umtx_wake(td, (void *)(uintptr_t)uaddrs[i], 4027 INT_MAX, 1); 4028 } 4029 maybe_yield(); 4030 } 4031 return (error); 4032 } 4033 4034 static int 4035 __umtx_op_nwake_private(struct thread *td, struct _umtx_op_args *uap, 4036 const struct umtx_copyops *ops) 4037 { 4038 4039 if (ops->compat32) 4040 return (__umtx_op_nwake_private_compat32(td, uap)); 4041 return (__umtx_op_nwake_private_native(td, uap)); 4042 } 4043 4044 static int 4045 __umtx_op_wake_private(struct thread *td, struct _umtx_op_args *uap, 4046 const struct umtx_copyops *ops __unused) 4047 { 4048 4049 return (kern_umtx_wake(td, uap->obj, uap->val, 1)); 4050 } 4051 4052 static int 4053 __umtx_op_lock_umutex(struct thread *td, struct _umtx_op_args *uap, 4054 const struct umtx_copyops *ops) 4055 { 4056 struct _umtx_time *tm_p, timeout; 4057 int error; 4058 4059 /* Allow a null timespec (wait forever). */ 4060 if (uap->uaddr2 == NULL) 4061 tm_p = NULL; 4062 else { 4063 error = ops->copyin_umtx_time( 4064 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 4065 if (error != 0) 4066 return (error); 4067 tm_p = &timeout; 4068 } 4069 return (do_lock_umutex(td, uap->obj, tm_p, 0)); 4070 } 4071 4072 static int 4073 __umtx_op_trylock_umutex(struct thread *td, struct _umtx_op_args *uap, 4074 const struct umtx_copyops *ops __unused) 4075 { 4076 4077 return (do_lock_umutex(td, uap->obj, NULL, _UMUTEX_TRY)); 4078 } 4079 4080 static int 4081 __umtx_op_wait_umutex(struct thread *td, struct _umtx_op_args *uap, 4082 const struct umtx_copyops *ops) 4083 { 4084 struct _umtx_time *tm_p, timeout; 4085 int error; 4086 4087 /* Allow a null timespec (wait forever). */ 4088 if (uap->uaddr2 == NULL) 4089 tm_p = NULL; 4090 else { 4091 error = ops->copyin_umtx_time( 4092 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 4093 if (error != 0) 4094 return (error); 4095 tm_p = &timeout; 4096 } 4097 return (do_lock_umutex(td, uap->obj, tm_p, _UMUTEX_WAIT)); 4098 } 4099 4100 static int 4101 __umtx_op_wake_umutex(struct thread *td, struct _umtx_op_args *uap, 4102 const struct umtx_copyops *ops __unused) 4103 { 4104 4105 return (do_wake_umutex(td, uap->obj)); 4106 } 4107 4108 static int 4109 __umtx_op_unlock_umutex(struct thread *td, struct _umtx_op_args *uap, 4110 const struct umtx_copyops *ops __unused) 4111 { 4112 4113 return (do_unlock_umutex(td, uap->obj, false)); 4114 } 4115 4116 static int 4117 __umtx_op_set_ceiling(struct thread *td, struct _umtx_op_args *uap, 4118 const struct umtx_copyops *ops __unused) 4119 { 4120 4121 return (do_set_ceiling(td, uap->obj, uap->val, uap->uaddr1)); 4122 } 4123 4124 static int 4125 __umtx_op_cv_wait(struct thread *td, struct _umtx_op_args *uap, 4126 const struct umtx_copyops *ops) 4127 { 4128 struct timespec *ts, timeout; 4129 int error; 4130 4131 /* Allow a null timespec (wait forever). */ 4132 if (uap->uaddr2 == NULL) 4133 ts = NULL; 4134 else { 4135 error = ops->copyin_timeout(uap->uaddr2, &timeout); 4136 if (error != 0) 4137 return (error); 4138 ts = &timeout; 4139 } 4140 return (do_cv_wait(td, uap->obj, uap->uaddr1, ts, uap->val)); 4141 } 4142 4143 static int 4144 __umtx_op_cv_signal(struct thread *td, struct _umtx_op_args *uap, 4145 const struct umtx_copyops *ops __unused) 4146 { 4147 4148 return (do_cv_signal(td, uap->obj)); 4149 } 4150 4151 static int 4152 __umtx_op_cv_broadcast(struct thread *td, struct _umtx_op_args *uap, 4153 const struct umtx_copyops *ops __unused) 4154 { 4155 4156 return (do_cv_broadcast(td, uap->obj)); 4157 } 4158 4159 static int 4160 __umtx_op_rw_rdlock(struct thread *td, struct _umtx_op_args *uap, 4161 const struct umtx_copyops *ops) 4162 { 4163 struct _umtx_time timeout; 4164 int error; 4165 4166 /* Allow a null timespec (wait forever). */ 4167 if (uap->uaddr2 == NULL) { 4168 error = do_rw_rdlock(td, uap->obj, uap->val, 0); 4169 } else { 4170 error = ops->copyin_umtx_time(uap->uaddr2, 4171 (size_t)uap->uaddr1, &timeout); 4172 if (error != 0) 4173 return (error); 4174 error = do_rw_rdlock(td, uap->obj, uap->val, &timeout); 4175 } 4176 return (error); 4177 } 4178 4179 static int 4180 __umtx_op_rw_wrlock(struct thread *td, struct _umtx_op_args *uap, 4181 const struct umtx_copyops *ops) 4182 { 4183 struct _umtx_time timeout; 4184 int error; 4185 4186 /* Allow a null timespec (wait forever). */ 4187 if (uap->uaddr2 == NULL) { 4188 error = do_rw_wrlock(td, uap->obj, 0); 4189 } else { 4190 error = ops->copyin_umtx_time(uap->uaddr2, 4191 (size_t)uap->uaddr1, &timeout); 4192 if (error != 0) 4193 return (error); 4194 4195 error = do_rw_wrlock(td, uap->obj, &timeout); 4196 } 4197 return (error); 4198 } 4199 4200 static int 4201 __umtx_op_rw_unlock(struct thread *td, struct _umtx_op_args *uap, 4202 const struct umtx_copyops *ops __unused) 4203 { 4204 4205 return (do_rw_unlock(td, uap->obj)); 4206 } 4207 4208 #if defined(COMPAT_FREEBSD9) || defined(COMPAT_FREEBSD10) 4209 static int 4210 __umtx_op_sem_wait(struct thread *td, struct _umtx_op_args *uap, 4211 const struct umtx_copyops *ops) 4212 { 4213 struct _umtx_time *tm_p, timeout; 4214 int error; 4215 4216 /* Allow a null timespec (wait forever). */ 4217 if (uap->uaddr2 == NULL) 4218 tm_p = NULL; 4219 else { 4220 error = ops->copyin_umtx_time( 4221 uap->uaddr2, (size_t)uap->uaddr1, &timeout); 4222 if (error != 0) 4223 return (error); 4224 tm_p = &timeout; 4225 } 4226 return (do_sem_wait(td, uap->obj, tm_p)); 4227 } 4228 4229 static int 4230 __umtx_op_sem_wake(struct thread *td, struct _umtx_op_args *uap, 4231 const struct umtx_copyops *ops __unused) 4232 { 4233 4234 return (do_sem_wake(td, uap->obj)); 4235 } 4236 #endif 4237 4238 static int 4239 __umtx_op_wake2_umutex(struct thread *td, struct _umtx_op_args *uap, 4240 const struct umtx_copyops *ops __unused) 4241 { 4242 4243 return (do_wake2_umutex(td, uap->obj, uap->val)); 4244 } 4245 4246 static int 4247 __umtx_op_sem2_wait(struct thread *td, struct _umtx_op_args *uap, 4248 const struct umtx_copyops *ops) 4249 { 4250 struct _umtx_time *tm_p, timeout; 4251 size_t uasize; 4252 int error; 4253 4254 /* Allow a null timespec (wait forever). */ 4255 if (uap->uaddr2 == NULL) { 4256 uasize = 0; 4257 tm_p = NULL; 4258 } else { 4259 uasize = (size_t)uap->uaddr1; 4260 error = ops->copyin_umtx_time(uap->uaddr2, uasize, &timeout); 4261 if (error != 0) 4262 return (error); 4263 tm_p = &timeout; 4264 } 4265 error = do_sem2_wait(td, uap->obj, tm_p); 4266 if (error == EINTR && uap->uaddr2 != NULL && 4267 (timeout._flags & UMTX_ABSTIME) == 0 && 4268 uasize >= ops->umtx_time_sz + ops->timespec_sz) { 4269 error = ops->copyout_timeout( 4270 (void *)((uintptr_t)uap->uaddr2 + ops->umtx_time_sz), 4271 uasize - ops->umtx_time_sz, &timeout._timeout); 4272 if (error == 0) { 4273 error = EINTR; 4274 } 4275 } 4276 4277 return (error); 4278 } 4279 4280 static int 4281 __umtx_op_sem2_wake(struct thread *td, struct _umtx_op_args *uap, 4282 const struct umtx_copyops *ops __unused) 4283 { 4284 4285 return (do_sem2_wake(td, uap->obj)); 4286 } 4287 4288 #define USHM_OBJ_UMTX(o) \ 4289 ((struct umtx_shm_obj_list *)(&(o)->umtx_data)) 4290 4291 #define USHMF_REG_LINKED 0x0001 4292 #define USHMF_OBJ_LINKED 0x0002 4293 struct umtx_shm_reg { 4294 TAILQ_ENTRY(umtx_shm_reg) ushm_reg_link; 4295 LIST_ENTRY(umtx_shm_reg) ushm_obj_link; 4296 struct umtx_key ushm_key; 4297 struct ucred *ushm_cred; 4298 struct shmfd *ushm_obj; 4299 u_int ushm_refcnt; 4300 u_int ushm_flags; 4301 }; 4302 4303 LIST_HEAD(umtx_shm_obj_list, umtx_shm_reg); 4304 TAILQ_HEAD(umtx_shm_reg_head, umtx_shm_reg); 4305 4306 static uma_zone_t umtx_shm_reg_zone; 4307 static struct umtx_shm_reg_head umtx_shm_registry[UMTX_CHAINS]; 4308 static struct mtx umtx_shm_lock; 4309 static struct umtx_shm_reg_head umtx_shm_reg_delfree = 4310 TAILQ_HEAD_INITIALIZER(umtx_shm_reg_delfree); 4311 4312 static void umtx_shm_free_reg(struct umtx_shm_reg *reg); 4313 4314 static void 4315 umtx_shm_reg_delfree_tq(void *context __unused, int pending __unused) 4316 { 4317 struct umtx_shm_reg_head d; 4318 struct umtx_shm_reg *reg, *reg1; 4319 4320 TAILQ_INIT(&d); 4321 mtx_lock(&umtx_shm_lock); 4322 TAILQ_CONCAT(&d, &umtx_shm_reg_delfree, ushm_reg_link); 4323 mtx_unlock(&umtx_shm_lock); 4324 TAILQ_FOREACH_SAFE(reg, &d, ushm_reg_link, reg1) { 4325 TAILQ_REMOVE(&d, reg, ushm_reg_link); 4326 umtx_shm_free_reg(reg); 4327 } 4328 } 4329 4330 static struct task umtx_shm_reg_delfree_task = 4331 TASK_INITIALIZER(0, umtx_shm_reg_delfree_tq, NULL); 4332 4333 static struct umtx_shm_reg * 4334 umtx_shm_find_reg_locked(const struct umtx_key *key) 4335 { 4336 struct umtx_shm_reg *reg; 4337 struct umtx_shm_reg_head *reg_head; 4338 4339 KASSERT(key->shared, ("umtx_p_find_rg: private key")); 4340 mtx_assert(&umtx_shm_lock, MA_OWNED); 4341 reg_head = &umtx_shm_registry[key->hash]; 4342 TAILQ_FOREACH(reg, reg_head, ushm_reg_link) { 4343 KASSERT(reg->ushm_key.shared, 4344 ("non-shared key on reg %p %d", reg, reg->ushm_key.shared)); 4345 if (reg->ushm_key.info.shared.object == 4346 key->info.shared.object && 4347 reg->ushm_key.info.shared.offset == 4348 key->info.shared.offset) { 4349 KASSERT(reg->ushm_key.type == TYPE_SHM, ("TYPE_USHM")); 4350 KASSERT(reg->ushm_refcnt > 0, 4351 ("reg %p refcnt 0 onlist", reg)); 4352 KASSERT((reg->ushm_flags & USHMF_REG_LINKED) != 0, 4353 ("reg %p not linked", reg)); 4354 reg->ushm_refcnt++; 4355 return (reg); 4356 } 4357 } 4358 return (NULL); 4359 } 4360 4361 static struct umtx_shm_reg * 4362 umtx_shm_find_reg(const struct umtx_key *key) 4363 { 4364 struct umtx_shm_reg *reg; 4365 4366 mtx_lock(&umtx_shm_lock); 4367 reg = umtx_shm_find_reg_locked(key); 4368 mtx_unlock(&umtx_shm_lock); 4369 return (reg); 4370 } 4371 4372 static void 4373 umtx_shm_free_reg(struct umtx_shm_reg *reg) 4374 { 4375 4376 chgumtxcnt(reg->ushm_cred->cr_ruidinfo, -1, 0); 4377 crfree(reg->ushm_cred); 4378 shm_drop(reg->ushm_obj); 4379 uma_zfree(umtx_shm_reg_zone, reg); 4380 } 4381 4382 static bool 4383 umtx_shm_unref_reg_locked(struct umtx_shm_reg *reg, bool force) 4384 { 4385 bool res; 4386 4387 mtx_assert(&umtx_shm_lock, MA_OWNED); 4388 KASSERT(reg->ushm_refcnt > 0, ("ushm_reg %p refcnt 0", reg)); 4389 reg->ushm_refcnt--; 4390 res = reg->ushm_refcnt == 0; 4391 if (res || force) { 4392 if ((reg->ushm_flags & USHMF_REG_LINKED) != 0) { 4393 TAILQ_REMOVE(&umtx_shm_registry[reg->ushm_key.hash], 4394 reg, ushm_reg_link); 4395 reg->ushm_flags &= ~USHMF_REG_LINKED; 4396 } 4397 if ((reg->ushm_flags & USHMF_OBJ_LINKED) != 0) { 4398 LIST_REMOVE(reg, ushm_obj_link); 4399 reg->ushm_flags &= ~USHMF_OBJ_LINKED; 4400 } 4401 } 4402 return (res); 4403 } 4404 4405 static void 4406 umtx_shm_unref_reg(struct umtx_shm_reg *reg, bool force) 4407 { 4408 vm_object_t object; 4409 bool dofree; 4410 4411 if (force) { 4412 object = reg->ushm_obj->shm_object; 4413 VM_OBJECT_WLOCK(object); 4414 vm_object_set_flag(object, OBJ_UMTXDEAD); 4415 VM_OBJECT_WUNLOCK(object); 4416 } 4417 mtx_lock(&umtx_shm_lock); 4418 dofree = umtx_shm_unref_reg_locked(reg, force); 4419 mtx_unlock(&umtx_shm_lock); 4420 if (dofree) 4421 umtx_shm_free_reg(reg); 4422 } 4423 4424 void 4425 umtx_shm_object_init(vm_object_t object) 4426 { 4427 4428 LIST_INIT(USHM_OBJ_UMTX(object)); 4429 } 4430 4431 void 4432 umtx_shm_object_terminated(vm_object_t object) 4433 { 4434 struct umtx_shm_reg *reg, *reg1; 4435 bool dofree; 4436 4437 if (LIST_EMPTY(USHM_OBJ_UMTX(object))) 4438 return; 4439 4440 dofree = false; 4441 mtx_lock(&umtx_shm_lock); 4442 LIST_FOREACH_SAFE(reg, USHM_OBJ_UMTX(object), ushm_obj_link, reg1) { 4443 if (umtx_shm_unref_reg_locked(reg, true)) { 4444 TAILQ_INSERT_TAIL(&umtx_shm_reg_delfree, reg, 4445 ushm_reg_link); 4446 dofree = true; 4447 } 4448 } 4449 mtx_unlock(&umtx_shm_lock); 4450 if (dofree) 4451 taskqueue_enqueue(taskqueue_thread, &umtx_shm_reg_delfree_task); 4452 } 4453 4454 static int 4455 umtx_shm_create_reg(struct thread *td, const struct umtx_key *key, 4456 struct umtx_shm_reg **res) 4457 { 4458 struct umtx_shm_reg *reg, *reg1; 4459 struct ucred *cred; 4460 int error; 4461 4462 reg = umtx_shm_find_reg(key); 4463 if (reg != NULL) { 4464 *res = reg; 4465 return (0); 4466 } 4467 cred = td->td_ucred; 4468 if (!chgumtxcnt(cred->cr_ruidinfo, 1, lim_cur(td, RLIMIT_UMTXP))) 4469 return (ENOMEM); 4470 reg = uma_zalloc(umtx_shm_reg_zone, M_WAITOK | M_ZERO); 4471 reg->ushm_refcnt = 1; 4472 bcopy(key, ®->ushm_key, sizeof(*key)); 4473 reg->ushm_obj = shm_alloc(td->td_ucred, O_RDWR, false); 4474 reg->ushm_cred = crhold(cred); 4475 error = shm_dotruncate(reg->ushm_obj, PAGE_SIZE); 4476 if (error != 0) { 4477 umtx_shm_free_reg(reg); 4478 return (error); 4479 } 4480 mtx_lock(&umtx_shm_lock); 4481 reg1 = umtx_shm_find_reg_locked(key); 4482 if (reg1 != NULL) { 4483 mtx_unlock(&umtx_shm_lock); 4484 umtx_shm_free_reg(reg); 4485 *res = reg1; 4486 return (0); 4487 } 4488 reg->ushm_refcnt++; 4489 TAILQ_INSERT_TAIL(&umtx_shm_registry[key->hash], reg, ushm_reg_link); 4490 LIST_INSERT_HEAD(USHM_OBJ_UMTX(key->info.shared.object), reg, 4491 ushm_obj_link); 4492 reg->ushm_flags = USHMF_REG_LINKED | USHMF_OBJ_LINKED; 4493 mtx_unlock(&umtx_shm_lock); 4494 *res = reg; 4495 return (0); 4496 } 4497 4498 static int 4499 umtx_shm_alive(struct thread *td, void *addr) 4500 { 4501 vm_map_t map; 4502 vm_map_entry_t entry; 4503 vm_object_t object; 4504 vm_pindex_t pindex; 4505 vm_prot_t prot; 4506 int res, ret; 4507 boolean_t wired; 4508 4509 map = &td->td_proc->p_vmspace->vm_map; 4510 res = vm_map_lookup(&map, (uintptr_t)addr, VM_PROT_READ, &entry, 4511 &object, &pindex, &prot, &wired); 4512 if (res != KERN_SUCCESS) 4513 return (EFAULT); 4514 if (object == NULL) 4515 ret = EINVAL; 4516 else 4517 ret = (object->flags & OBJ_UMTXDEAD) != 0 ? ENOTTY : 0; 4518 vm_map_lookup_done(map, entry); 4519 return (ret); 4520 } 4521 4522 static void 4523 umtx_shm_init(void) 4524 { 4525 int i; 4526 4527 umtx_shm_reg_zone = uma_zcreate("umtx_shm", sizeof(struct umtx_shm_reg), 4528 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 4529 mtx_init(&umtx_shm_lock, "umtxshm", NULL, MTX_DEF); 4530 for (i = 0; i < nitems(umtx_shm_registry); i++) 4531 TAILQ_INIT(&umtx_shm_registry[i]); 4532 } 4533 4534 static int 4535 umtx_shm(struct thread *td, void *addr, u_int flags) 4536 { 4537 struct umtx_key key; 4538 struct umtx_shm_reg *reg; 4539 struct file *fp; 4540 int error, fd; 4541 4542 if (__bitcount(flags & (UMTX_SHM_CREAT | UMTX_SHM_LOOKUP | 4543 UMTX_SHM_DESTROY| UMTX_SHM_ALIVE)) != 1) 4544 return (EINVAL); 4545 if ((flags & UMTX_SHM_ALIVE) != 0) 4546 return (umtx_shm_alive(td, addr)); 4547 error = umtx_key_get(addr, TYPE_SHM, PROCESS_SHARE, &key); 4548 if (error != 0) 4549 return (error); 4550 KASSERT(key.shared == 1, ("non-shared key")); 4551 if ((flags & UMTX_SHM_CREAT) != 0) { 4552 error = umtx_shm_create_reg(td, &key, ®); 4553 } else { 4554 reg = umtx_shm_find_reg(&key); 4555 if (reg == NULL) 4556 error = ESRCH; 4557 } 4558 umtx_key_release(&key); 4559 if (error != 0) 4560 return (error); 4561 KASSERT(reg != NULL, ("no reg")); 4562 if ((flags & UMTX_SHM_DESTROY) != 0) { 4563 umtx_shm_unref_reg(reg, true); 4564 } else { 4565 #if 0 4566 #ifdef MAC 4567 error = mac_posixshm_check_open(td->td_ucred, 4568 reg->ushm_obj, FFLAGS(O_RDWR)); 4569 if (error == 0) 4570 #endif 4571 error = shm_access(reg->ushm_obj, td->td_ucred, 4572 FFLAGS(O_RDWR)); 4573 if (error == 0) 4574 #endif 4575 error = falloc_caps(td, &fp, &fd, O_CLOEXEC, NULL); 4576 if (error == 0) { 4577 shm_hold(reg->ushm_obj); 4578 finit(fp, FFLAGS(O_RDWR), DTYPE_SHM, reg->ushm_obj, 4579 &shm_ops); 4580 td->td_retval[0] = fd; 4581 fdrop(fp, td); 4582 } 4583 } 4584 umtx_shm_unref_reg(reg, false); 4585 return (error); 4586 } 4587 4588 static int 4589 __umtx_op_shm(struct thread *td, struct _umtx_op_args *uap, 4590 const struct umtx_copyops *ops __unused) 4591 { 4592 4593 return (umtx_shm(td, uap->uaddr1, uap->val)); 4594 } 4595 4596 static int 4597 __umtx_op_robust_lists(struct thread *td, struct _umtx_op_args *uap, 4598 const struct umtx_copyops *ops) 4599 { 4600 struct umtx_robust_lists_params rb; 4601 int error; 4602 4603 if (ops->compat32) { 4604 if ((td->td_pflags2 & TDP2_COMPAT32RB) == 0 && 4605 (td->td_rb_list != 0 || td->td_rbp_list != 0 || 4606 td->td_rb_inact != 0)) 4607 return (EBUSY); 4608 } else if ((td->td_pflags2 & TDP2_COMPAT32RB) != 0) { 4609 return (EBUSY); 4610 } 4611 4612 bzero(&rb, sizeof(rb)); 4613 error = ops->copyin_robust_lists(uap->uaddr1, uap->val, &rb); 4614 if (error != 0) 4615 return (error); 4616 4617 if (ops->compat32) 4618 td->td_pflags2 |= TDP2_COMPAT32RB; 4619 4620 td->td_rb_list = rb.robust_list_offset; 4621 td->td_rbp_list = rb.robust_priv_list_offset; 4622 td->td_rb_inact = rb.robust_inact_offset; 4623 return (0); 4624 } 4625 4626 static int 4627 __umtx_op_get_min_timeout(struct thread *td, struct _umtx_op_args *uap, 4628 const struct umtx_copyops *ops) 4629 { 4630 long val; 4631 int error, val1; 4632 4633 val = sbttons(td->td_proc->p_umtx_min_timeout); 4634 if (ops->compat32) { 4635 val1 = (int)val; 4636 error = copyout(&val1, uap->uaddr1, sizeof(val1)); 4637 } else { 4638 error = copyout(&val, uap->uaddr1, sizeof(val)); 4639 } 4640 return (error); 4641 } 4642 4643 static int 4644 __umtx_op_set_min_timeout(struct thread *td, struct _umtx_op_args *uap, 4645 const struct umtx_copyops *ops) 4646 { 4647 if (uap->val < 0) 4648 return (EINVAL); 4649 td->td_proc->p_umtx_min_timeout = nstosbt(uap->val); 4650 return (0); 4651 } 4652 4653 #if defined(__i386__) || defined(__amd64__) 4654 /* 4655 * Provide the standard 32-bit definitions for x86, since native/compat32 use a 4656 * 32-bit time_t there. Other architectures just need the i386 definitions 4657 * along with their standard compat32. 4658 */ 4659 struct timespecx32 { 4660 int64_t tv_sec; 4661 int32_t tv_nsec; 4662 }; 4663 4664 struct umtx_timex32 { 4665 struct timespecx32 _timeout; 4666 uint32_t _flags; 4667 uint32_t _clockid; 4668 }; 4669 4670 #ifndef __i386__ 4671 #define timespeci386 timespec32 4672 #define umtx_timei386 umtx_time32 4673 #endif 4674 #else /* !__i386__ && !__amd64__ */ 4675 /* 32-bit architectures can emulate i386, so define these almost everywhere. */ 4676 struct timespeci386 { 4677 int32_t tv_sec; 4678 int32_t tv_nsec; 4679 }; 4680 4681 struct umtx_timei386 { 4682 struct timespeci386 _timeout; 4683 uint32_t _flags; 4684 uint32_t _clockid; 4685 }; 4686 4687 #if defined(__LP64__) 4688 #define timespecx32 timespec32 4689 #define umtx_timex32 umtx_time32 4690 #endif 4691 #endif 4692 4693 static int 4694 umtx_copyin_robust_lists32(const void *uaddr, size_t size, 4695 struct umtx_robust_lists_params *rbp) 4696 { 4697 struct umtx_robust_lists_params_compat32 rb32; 4698 int error; 4699 4700 if (size > sizeof(rb32)) 4701 return (EINVAL); 4702 bzero(&rb32, sizeof(rb32)); 4703 error = copyin(uaddr, &rb32, size); 4704 if (error != 0) 4705 return (error); 4706 CP(rb32, *rbp, robust_list_offset); 4707 CP(rb32, *rbp, robust_priv_list_offset); 4708 CP(rb32, *rbp, robust_inact_offset); 4709 return (0); 4710 } 4711 4712 #ifndef __i386__ 4713 static inline int 4714 umtx_copyin_timeouti386(const void *uaddr, struct timespec *tsp) 4715 { 4716 struct timespeci386 ts32; 4717 int error; 4718 4719 error = copyin(uaddr, &ts32, sizeof(ts32)); 4720 if (error == 0) { 4721 if (!timespecvalid_interval(&ts32)) 4722 error = EINVAL; 4723 else { 4724 CP(ts32, *tsp, tv_sec); 4725 CP(ts32, *tsp, tv_nsec); 4726 } 4727 } 4728 return (error); 4729 } 4730 4731 static inline int 4732 umtx_copyin_umtx_timei386(const void *uaddr, size_t size, struct _umtx_time *tp) 4733 { 4734 struct umtx_timei386 t32; 4735 int error; 4736 4737 t32._clockid = CLOCK_REALTIME; 4738 t32._flags = 0; 4739 if (size <= sizeof(t32._timeout)) 4740 error = copyin(uaddr, &t32._timeout, sizeof(t32._timeout)); 4741 else 4742 error = copyin(uaddr, &t32, sizeof(t32)); 4743 if (error != 0) 4744 return (error); 4745 if (!timespecvalid_interval(&t32._timeout)) 4746 return (EINVAL); 4747 TS_CP(t32, *tp, _timeout); 4748 CP(t32, *tp, _flags); 4749 CP(t32, *tp, _clockid); 4750 return (0); 4751 } 4752 4753 static int 4754 umtx_copyout_timeouti386(void *uaddr, size_t sz, struct timespec *tsp) 4755 { 4756 struct timespeci386 remain32 = { 4757 .tv_sec = tsp->tv_sec, 4758 .tv_nsec = tsp->tv_nsec, 4759 }; 4760 4761 /* 4762 * Should be guaranteed by the caller, sz == uaddr1 - sizeof(_umtx_time) 4763 * and we're only called if sz >= sizeof(timespec) as supplied in the 4764 * copyops. 4765 */ 4766 KASSERT(sz >= sizeof(remain32), 4767 ("umtx_copyops specifies incorrect sizes")); 4768 4769 return (copyout(&remain32, uaddr, sizeof(remain32))); 4770 } 4771 #endif /* !__i386__ */ 4772 4773 #if defined(__i386__) || defined(__LP64__) 4774 static inline int 4775 umtx_copyin_timeoutx32(const void *uaddr, struct timespec *tsp) 4776 { 4777 struct timespecx32 ts32; 4778 int error; 4779 4780 error = copyin(uaddr, &ts32, sizeof(ts32)); 4781 if (error == 0) { 4782 if (!timespecvalid_interval(&ts32)) 4783 error = EINVAL; 4784 else { 4785 CP(ts32, *tsp, tv_sec); 4786 CP(ts32, *tsp, tv_nsec); 4787 } 4788 } 4789 return (error); 4790 } 4791 4792 static inline int 4793 umtx_copyin_umtx_timex32(const void *uaddr, size_t size, struct _umtx_time *tp) 4794 { 4795 struct umtx_timex32 t32; 4796 int error; 4797 4798 t32._clockid = CLOCK_REALTIME; 4799 t32._flags = 0; 4800 if (size <= sizeof(t32._timeout)) 4801 error = copyin(uaddr, &t32._timeout, sizeof(t32._timeout)); 4802 else 4803 error = copyin(uaddr, &t32, sizeof(t32)); 4804 if (error != 0) 4805 return (error); 4806 if (!timespecvalid_interval(&t32._timeout)) 4807 return (EINVAL); 4808 TS_CP(t32, *tp, _timeout); 4809 CP(t32, *tp, _flags); 4810 CP(t32, *tp, _clockid); 4811 return (0); 4812 } 4813 4814 static int 4815 umtx_copyout_timeoutx32(void *uaddr, size_t sz, struct timespec *tsp) 4816 { 4817 struct timespecx32 remain32 = { 4818 .tv_sec = tsp->tv_sec, 4819 .tv_nsec = tsp->tv_nsec, 4820 }; 4821 4822 /* 4823 * Should be guaranteed by the caller, sz == uaddr1 - sizeof(_umtx_time) 4824 * and we're only called if sz >= sizeof(timespec) as supplied in the 4825 * copyops. 4826 */ 4827 KASSERT(sz >= sizeof(remain32), 4828 ("umtx_copyops specifies incorrect sizes")); 4829 4830 return (copyout(&remain32, uaddr, sizeof(remain32))); 4831 } 4832 #endif /* __i386__ || __LP64__ */ 4833 4834 typedef int (*_umtx_op_func)(struct thread *td, struct _umtx_op_args *uap, 4835 const struct umtx_copyops *umtx_ops); 4836 4837 static const _umtx_op_func op_table[] = { 4838 #ifdef COMPAT_FREEBSD10 4839 [UMTX_OP_LOCK] = __umtx_op_lock_umtx, 4840 [UMTX_OP_UNLOCK] = __umtx_op_unlock_umtx, 4841 #else 4842 [UMTX_OP_LOCK] = __umtx_op_unimpl, 4843 [UMTX_OP_UNLOCK] = __umtx_op_unimpl, 4844 #endif 4845 [UMTX_OP_WAIT] = __umtx_op_wait, 4846 [UMTX_OP_WAKE] = __umtx_op_wake, 4847 [UMTX_OP_MUTEX_TRYLOCK] = __umtx_op_trylock_umutex, 4848 [UMTX_OP_MUTEX_LOCK] = __umtx_op_lock_umutex, 4849 [UMTX_OP_MUTEX_UNLOCK] = __umtx_op_unlock_umutex, 4850 [UMTX_OP_SET_CEILING] = __umtx_op_set_ceiling, 4851 [UMTX_OP_CV_WAIT] = __umtx_op_cv_wait, 4852 [UMTX_OP_CV_SIGNAL] = __umtx_op_cv_signal, 4853 [UMTX_OP_CV_BROADCAST] = __umtx_op_cv_broadcast, 4854 [UMTX_OP_WAIT_UINT] = __umtx_op_wait_uint, 4855 [UMTX_OP_RW_RDLOCK] = __umtx_op_rw_rdlock, 4856 [UMTX_OP_RW_WRLOCK] = __umtx_op_rw_wrlock, 4857 [UMTX_OP_RW_UNLOCK] = __umtx_op_rw_unlock, 4858 [UMTX_OP_WAIT_UINT_PRIVATE] = __umtx_op_wait_uint_private, 4859 [UMTX_OP_WAKE_PRIVATE] = __umtx_op_wake_private, 4860 [UMTX_OP_MUTEX_WAIT] = __umtx_op_wait_umutex, 4861 [UMTX_OP_MUTEX_WAKE] = __umtx_op_wake_umutex, 4862 #if defined(COMPAT_FREEBSD9) || defined(COMPAT_FREEBSD10) 4863 [UMTX_OP_SEM_WAIT] = __umtx_op_sem_wait, 4864 [UMTX_OP_SEM_WAKE] = __umtx_op_sem_wake, 4865 #else 4866 [UMTX_OP_SEM_WAIT] = __umtx_op_unimpl, 4867 [UMTX_OP_SEM_WAKE] = __umtx_op_unimpl, 4868 #endif 4869 [UMTX_OP_NWAKE_PRIVATE] = __umtx_op_nwake_private, 4870 [UMTX_OP_MUTEX_WAKE2] = __umtx_op_wake2_umutex, 4871 [UMTX_OP_SEM2_WAIT] = __umtx_op_sem2_wait, 4872 [UMTX_OP_SEM2_WAKE] = __umtx_op_sem2_wake, 4873 [UMTX_OP_SHM] = __umtx_op_shm, 4874 [UMTX_OP_ROBUST_LISTS] = __umtx_op_robust_lists, 4875 [UMTX_OP_GET_MIN_TIMEOUT] = __umtx_op_get_min_timeout, 4876 [UMTX_OP_SET_MIN_TIMEOUT] = __umtx_op_set_min_timeout, 4877 }; 4878 4879 static const struct umtx_copyops umtx_native_ops = { 4880 .copyin_timeout = umtx_copyin_timeout, 4881 .copyin_umtx_time = umtx_copyin_umtx_time, 4882 .copyin_robust_lists = umtx_copyin_robust_lists, 4883 .copyout_timeout = umtx_copyout_timeout, 4884 .timespec_sz = sizeof(struct timespec), 4885 .umtx_time_sz = sizeof(struct _umtx_time), 4886 }; 4887 4888 #ifndef __i386__ 4889 static const struct umtx_copyops umtx_native_opsi386 = { 4890 .copyin_timeout = umtx_copyin_timeouti386, 4891 .copyin_umtx_time = umtx_copyin_umtx_timei386, 4892 .copyin_robust_lists = umtx_copyin_robust_lists32, 4893 .copyout_timeout = umtx_copyout_timeouti386, 4894 .timespec_sz = sizeof(struct timespeci386), 4895 .umtx_time_sz = sizeof(struct umtx_timei386), 4896 .compat32 = true, 4897 }; 4898 #endif 4899 4900 #if defined(__i386__) || defined(__LP64__) 4901 /* i386 can emulate other 32-bit archs, too! */ 4902 static const struct umtx_copyops umtx_native_opsx32 = { 4903 .copyin_timeout = umtx_copyin_timeoutx32, 4904 .copyin_umtx_time = umtx_copyin_umtx_timex32, 4905 .copyin_robust_lists = umtx_copyin_robust_lists32, 4906 .copyout_timeout = umtx_copyout_timeoutx32, 4907 .timespec_sz = sizeof(struct timespecx32), 4908 .umtx_time_sz = sizeof(struct umtx_timex32), 4909 .compat32 = true, 4910 }; 4911 4912 #ifdef COMPAT_FREEBSD32 4913 #ifdef __amd64__ 4914 #define umtx_native_ops32 umtx_native_opsi386 4915 #else 4916 #define umtx_native_ops32 umtx_native_opsx32 4917 #endif 4918 #endif /* COMPAT_FREEBSD32 */ 4919 #endif /* __i386__ || __LP64__ */ 4920 4921 #define UMTX_OP__FLAGS (UMTX_OP__32BIT | UMTX_OP__I386) 4922 4923 static int 4924 kern__umtx_op(struct thread *td, void *obj, int op, unsigned long val, 4925 void *uaddr1, void *uaddr2, const struct umtx_copyops *ops) 4926 { 4927 struct _umtx_op_args uap = { 4928 .obj = obj, 4929 .op = op & ~UMTX_OP__FLAGS, 4930 .val = val, 4931 .uaddr1 = uaddr1, 4932 .uaddr2 = uaddr2 4933 }; 4934 4935 if ((uap.op >= nitems(op_table))) 4936 return (EINVAL); 4937 return ((*op_table[uap.op])(td, &uap, ops)); 4938 } 4939 4940 int 4941 sys__umtx_op(struct thread *td, struct _umtx_op_args *uap) 4942 { 4943 static const struct umtx_copyops *umtx_ops; 4944 4945 umtx_ops = &umtx_native_ops; 4946 #ifdef __LP64__ 4947 if ((uap->op & (UMTX_OP__32BIT | UMTX_OP__I386)) != 0) { 4948 if ((uap->op & UMTX_OP__I386) != 0) 4949 umtx_ops = &umtx_native_opsi386; 4950 else 4951 umtx_ops = &umtx_native_opsx32; 4952 } 4953 #elif !defined(__i386__) 4954 /* We consider UMTX_OP__32BIT a nop on !i386 ILP32. */ 4955 if ((uap->op & UMTX_OP__I386) != 0) 4956 umtx_ops = &umtx_native_opsi386; 4957 #else 4958 /* Likewise, UMTX_OP__I386 is a nop on i386. */ 4959 if ((uap->op & UMTX_OP__32BIT) != 0) 4960 umtx_ops = &umtx_native_opsx32; 4961 #endif 4962 return (kern__umtx_op(td, uap->obj, uap->op, uap->val, uap->uaddr1, 4963 uap->uaddr2, umtx_ops)); 4964 } 4965 4966 #ifdef COMPAT_FREEBSD32 4967 #ifdef COMPAT_FREEBSD10 4968 int 4969 freebsd10_freebsd32__umtx_lock(struct thread *td, 4970 struct freebsd10_freebsd32__umtx_lock_args *uap) 4971 { 4972 return (do_lock_umtx32(td, (uint32_t *)uap->umtx, td->td_tid, NULL)); 4973 } 4974 4975 int 4976 freebsd10_freebsd32__umtx_unlock(struct thread *td, 4977 struct freebsd10_freebsd32__umtx_unlock_args *uap) 4978 { 4979 return (do_unlock_umtx32(td, (uint32_t *)uap->umtx, td->td_tid)); 4980 } 4981 #endif /* COMPAT_FREEBSD10 */ 4982 4983 int 4984 freebsd32__umtx_op(struct thread *td, struct freebsd32__umtx_op_args *uap) 4985 { 4986 4987 return (kern__umtx_op(td, uap->obj, uap->op, uap->val, uap->uaddr1, 4988 uap->uaddr2, &umtx_native_ops32)); 4989 } 4990 #endif /* COMPAT_FREEBSD32 */ 4991 4992 void 4993 umtx_thread_init(struct thread *td) 4994 { 4995 4996 td->td_umtxq = umtxq_alloc(); 4997 td->td_umtxq->uq_thread = td; 4998 } 4999 5000 void 5001 umtx_thread_fini(struct thread *td) 5002 { 5003 5004 umtxq_free(td->td_umtxq); 5005 } 5006 5007 /* 5008 * It will be called when new thread is created, e.g fork(). 5009 */ 5010 void 5011 umtx_thread_alloc(struct thread *td) 5012 { 5013 struct umtx_q *uq; 5014 5015 uq = td->td_umtxq; 5016 uq->uq_inherited_pri = PRI_MAX; 5017 5018 KASSERT(uq->uq_flags == 0, ("uq_flags != 0")); 5019 KASSERT(uq->uq_thread == td, ("uq_thread != td")); 5020 KASSERT(uq->uq_pi_blocked == NULL, ("uq_pi_blocked != NULL")); 5021 KASSERT(TAILQ_EMPTY(&uq->uq_pi_contested), ("uq_pi_contested is not empty")); 5022 } 5023 5024 /* 5025 * exec() hook. 5026 * 5027 * Clear robust lists for all process' threads, not delaying the 5028 * cleanup to thread exit, since the relevant address space is 5029 * destroyed right now. 5030 */ 5031 void 5032 umtx_exec(struct proc *p) 5033 { 5034 struct thread *td; 5035 5036 KASSERT(p == curproc, ("need curproc")); 5037 KASSERT((p->p_flag & P_HADTHREADS) == 0 || 5038 (p->p_flag & P_STOPPED_SINGLE) != 0, 5039 ("curproc must be single-threaded")); 5040 /* 5041 * There is no need to lock the list as only this thread can be 5042 * running. 5043 */ 5044 FOREACH_THREAD_IN_PROC(p, td) { 5045 KASSERT(td == curthread || 5046 ((td->td_flags & TDF_BOUNDARY) != 0 && TD_IS_SUSPENDED(td)), 5047 ("running thread %p %p", p, td)); 5048 umtx_thread_cleanup(td); 5049 td->td_rb_list = td->td_rbp_list = td->td_rb_inact = 0; 5050 } 5051 5052 p->p_umtx_min_timeout = 0; 5053 } 5054 5055 /* 5056 * thread exit hook. 5057 */ 5058 void 5059 umtx_thread_exit(struct thread *td) 5060 { 5061 5062 umtx_thread_cleanup(td); 5063 } 5064 5065 static int 5066 umtx_read_uptr(struct thread *td, uintptr_t ptr, uintptr_t *res, bool compat32) 5067 { 5068 u_long res1; 5069 uint32_t res32; 5070 int error; 5071 5072 if (compat32) { 5073 error = fueword32((void *)ptr, &res32); 5074 if (error == 0) 5075 res1 = res32; 5076 } else { 5077 error = fueword((void *)ptr, &res1); 5078 } 5079 if (error == 0) 5080 *res = res1; 5081 else 5082 error = EFAULT; 5083 return (error); 5084 } 5085 5086 static void 5087 umtx_read_rb_list(struct thread *td, struct umutex *m, uintptr_t *rb_list, 5088 bool compat32) 5089 { 5090 struct umutex32 m32; 5091 5092 if (compat32) { 5093 memcpy(&m32, m, sizeof(m32)); 5094 *rb_list = m32.m_rb_lnk; 5095 } else { 5096 *rb_list = m->m_rb_lnk; 5097 } 5098 } 5099 5100 static int 5101 umtx_handle_rb(struct thread *td, uintptr_t rbp, uintptr_t *rb_list, bool inact, 5102 bool compat32) 5103 { 5104 struct umutex m; 5105 int error; 5106 5107 KASSERT(td->td_proc == curproc, ("need current vmspace")); 5108 error = copyin((void *)rbp, &m, sizeof(m)); 5109 if (error != 0) 5110 return (error); 5111 if (rb_list != NULL) 5112 umtx_read_rb_list(td, &m, rb_list, compat32); 5113 if ((m.m_flags & UMUTEX_ROBUST) == 0) 5114 return (EINVAL); 5115 if ((m.m_owner & ~UMUTEX_CONTESTED) != td->td_tid) 5116 /* inact is cleared after unlock, allow the inconsistency */ 5117 return (inact ? 0 : EINVAL); 5118 return (do_unlock_umutex(td, (struct umutex *)rbp, true)); 5119 } 5120 5121 static void 5122 umtx_cleanup_rb_list(struct thread *td, uintptr_t rb_list, uintptr_t *rb_inact, 5123 const char *name, bool compat32) 5124 { 5125 int error, i; 5126 uintptr_t rbp; 5127 bool inact; 5128 5129 if (rb_list == 0) 5130 return; 5131 error = umtx_read_uptr(td, rb_list, &rbp, compat32); 5132 for (i = 0; error == 0 && rbp != 0 && i < umtx_max_rb; i++) { 5133 if (rbp == *rb_inact) { 5134 inact = true; 5135 *rb_inact = 0; 5136 } else 5137 inact = false; 5138 error = umtx_handle_rb(td, rbp, &rbp, inact, compat32); 5139 } 5140 if (i == umtx_max_rb && umtx_verbose_rb) { 5141 uprintf("comm %s pid %d: reached umtx %smax rb %d\n", 5142 td->td_proc->p_comm, td->td_proc->p_pid, name, umtx_max_rb); 5143 } 5144 if (error != 0 && umtx_verbose_rb) { 5145 uprintf("comm %s pid %d: handling %srb error %d\n", 5146 td->td_proc->p_comm, td->td_proc->p_pid, name, error); 5147 } 5148 } 5149 5150 /* 5151 * Clean up umtx data. 5152 */ 5153 static void 5154 umtx_thread_cleanup(struct thread *td) 5155 { 5156 struct umtx_q *uq; 5157 struct umtx_pi *pi; 5158 uintptr_t rb_inact; 5159 bool compat32; 5160 5161 /* 5162 * Disown pi mutexes. 5163 */ 5164 uq = td->td_umtxq; 5165 if (uq != NULL) { 5166 if (uq->uq_inherited_pri != PRI_MAX || 5167 !TAILQ_EMPTY(&uq->uq_pi_contested)) { 5168 mtx_lock(&umtx_lock); 5169 uq->uq_inherited_pri = PRI_MAX; 5170 while ((pi = TAILQ_FIRST(&uq->uq_pi_contested)) != NULL) { 5171 pi->pi_owner = NULL; 5172 TAILQ_REMOVE(&uq->uq_pi_contested, pi, pi_link); 5173 } 5174 mtx_unlock(&umtx_lock); 5175 } 5176 sched_lend_user_prio_cond(td, PRI_MAX); 5177 } 5178 5179 compat32 = (td->td_pflags2 & TDP2_COMPAT32RB) != 0; 5180 td->td_pflags2 &= ~TDP2_COMPAT32RB; 5181 5182 if (td->td_rb_inact == 0 && td->td_rb_list == 0 && td->td_rbp_list == 0) 5183 return; 5184 5185 /* 5186 * Handle terminated robust mutexes. Must be done after 5187 * robust pi disown, otherwise unlock could see unowned 5188 * entries. 5189 */ 5190 rb_inact = td->td_rb_inact; 5191 if (rb_inact != 0) 5192 (void)umtx_read_uptr(td, rb_inact, &rb_inact, compat32); 5193 umtx_cleanup_rb_list(td, td->td_rb_list, &rb_inact, "", compat32); 5194 umtx_cleanup_rb_list(td, td->td_rbp_list, &rb_inact, "priv ", compat32); 5195 if (rb_inact != 0) 5196 (void)umtx_handle_rb(td, rb_inact, NULL, true, compat32); 5197 } 5198