1 /* 2 * Copyright (c) 2004, David Xu <davidxu@freebsd.org> 3 * Copyright (c) 2002, Jeffrey Roberson <jeff@freebsd.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice unmodified, this list of conditions, and the following 11 * disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/param.h> 32 #include <sys/kernel.h> 33 #include <sys/limits.h> 34 #include <sys/lock.h> 35 #include <sys/malloc.h> 36 #include <sys/mutex.h> 37 #include <sys/proc.h> 38 #include <sys/sysent.h> 39 #include <sys/systm.h> 40 #include <sys/sysproto.h> 41 #include <sys/eventhandler.h> 42 #include <sys/thr.h> 43 #include <sys/umtx.h> 44 45 #include <vm/vm.h> 46 #include <vm/vm_param.h> 47 #include <vm/pmap.h> 48 #include <vm/vm_map.h> 49 #include <vm/vm_object.h> 50 51 #define UMTX_PRIVATE 0 52 #define UMTX_SHARED 1 53 54 #define UMTX_STATIC_SHARED 55 56 struct umtx_key { 57 int type; 58 union { 59 struct { 60 vm_object_t object; 61 long offset; 62 } shared; 63 struct { 64 struct umtx *umtx; 65 long pid; 66 } private; 67 struct { 68 void *ptr; 69 long word; 70 } both; 71 } info; 72 }; 73 74 struct umtx_q { 75 LIST_ENTRY(umtx_q) uq_next; /* Linked list for the hash. */ 76 struct umtx_key uq_key; /* Umtx key. */ 77 struct thread *uq_thread; /* The thread waits on */ 78 LIST_ENTRY(umtx_q) uq_rqnext; /* Linked list for requeuing. */ 79 vm_offset_t uq_addr; /* Umtx's virtual address. */ 80 }; 81 82 LIST_HEAD(umtx_head, umtx_q); 83 struct umtxq_chain { 84 struct mtx uc_lock; /* Lock for this chain. */ 85 struct umtx_head uc_queue; /* List of sleep queues. */ 86 }; 87 88 #define GOLDEN_RATIO_PRIME 2654404609U 89 #define UMTX_CHAINS 128 90 #define UMTX_SHIFTS (__WORD_BIT - 7) 91 92 static struct umtxq_chain umtxq_chains[UMTX_CHAINS]; 93 static MALLOC_DEFINE(M_UMTX, "umtx", "UMTX queue memory"); 94 95 #define UMTX_CONTESTED LONG_MIN 96 97 static void umtxq_init_chains(void *); 98 static int umtxq_hash(struct umtx_key *key); 99 static struct mtx *umtxq_mtx(int chain); 100 static void umtxq_lock(struct umtx_key *key); 101 static void umtxq_unlock(struct umtx_key *key); 102 static void umtxq_insert(struct umtx_q *uq); 103 static void umtxq_remove(struct umtx_q *uq); 104 static int umtxq_sleep(struct thread *td, struct umtx_key *key, 105 int prio, const char *wmesg, int timo); 106 static int umtxq_count(struct umtx_key *key); 107 static void umtxq_signal(struct umtx_key *key); 108 static void umtxq_broadcast(struct umtx_key *key); 109 #ifdef UMTX_DYNAMIC_SHARED 110 static void fork_handler(void *arg, struct proc *p1, struct proc *p2, 111 int flags); 112 #endif 113 static int umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2); 114 static int umtx_key_get(struct thread *td, struct umtx *umtx, 115 struct umtx_key *key); 116 static void umtx_key_release(struct umtx_key *key); 117 118 SYSINIT(umtx, SI_SUB_EVENTHANDLER+1, SI_ORDER_MIDDLE, umtxq_init_chains, NULL); 119 120 static void 121 umtxq_init_chains(void *arg __unused) 122 { 123 int i; 124 125 for (i = 0; i < UMTX_CHAINS; ++i) { 126 mtx_init(&umtxq_chains[i].uc_lock, "umtxq_lock", NULL, 127 MTX_DEF | MTX_DUPOK); 128 LIST_INIT(&umtxq_chains[i].uc_queue); 129 } 130 #ifdef UMTX_DYNAMIC_SHARED 131 EVENTHANDLER_REGISTER(process_fork, fork_handler, 0, 10000); 132 #endif 133 } 134 135 static inline int 136 umtxq_hash(struct umtx_key *key) 137 { 138 unsigned n = (uintptr_t)key->info.both.ptr + key->info.both.word; 139 return (((n * GOLDEN_RATIO_PRIME) >> UMTX_SHIFTS) % UMTX_CHAINS); 140 } 141 142 static inline int 143 umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2) 144 { 145 return (k1->type == k2->type && 146 k1->info.both.ptr == k2->info.both.ptr && 147 k1->info.both.word == k2->info.both.word); 148 } 149 150 static inline struct mtx * 151 umtxq_mtx(int chain) 152 { 153 return (&umtxq_chains[chain].uc_lock); 154 } 155 156 static inline void 157 umtxq_lock(struct umtx_key *key) 158 { 159 int chain = umtxq_hash(key); 160 mtx_lock(umtxq_mtx(chain)); 161 } 162 163 static inline void 164 umtxq_unlock(struct umtx_key *key) 165 { 166 int chain = umtxq_hash(key); 167 mtx_unlock(umtxq_mtx(chain)); 168 } 169 170 /* 171 * Insert a thread onto the umtx queue. 172 */ 173 static inline void 174 umtxq_insert(struct umtx_q *uq) 175 { 176 struct umtx_head *head; 177 int chain = umtxq_hash(&uq->uq_key); 178 179 head = &umtxq_chains[chain].uc_queue; 180 LIST_INSERT_HEAD(head, uq, uq_next); 181 uq->uq_thread->td_umtxq = uq; 182 mtx_lock_spin(&sched_lock); 183 uq->uq_thread->td_flags |= TDF_UMTXQ; 184 mtx_unlock_spin(&sched_lock); 185 } 186 187 /* 188 * Remove thread from the umtx queue. 189 */ 190 static inline void 191 umtxq_remove(struct umtx_q *uq) 192 { 193 if (uq->uq_thread->td_flags & TDF_UMTXQ) { 194 LIST_REMOVE(uq, uq_next); 195 uq->uq_thread->td_umtxq = NULL; 196 /* turning off TDF_UMTXQ should be the last thing. */ 197 mtx_lock_spin(&sched_lock); 198 uq->uq_thread->td_flags &= ~TDF_UMTXQ; 199 mtx_unlock_spin(&sched_lock); 200 } 201 } 202 203 static int 204 umtxq_count(struct umtx_key *key) 205 { 206 struct umtx_q *uq; 207 struct umtx_head *head; 208 int chain, count = 0; 209 210 chain = umtxq_hash(key); 211 umtxq_lock(key); 212 head = &umtxq_chains[chain].uc_queue; 213 LIST_FOREACH(uq, head, uq_next) { 214 if (umtx_key_match(&uq->uq_key, key)) { 215 if (++count > 1) 216 break; 217 } 218 } 219 umtxq_unlock(key); 220 return (count); 221 } 222 223 static void 224 umtxq_signal(struct umtx_key *key) 225 { 226 struct umtx_q *uq; 227 struct umtx_head *head; 228 struct thread *blocked = NULL; 229 int chain; 230 231 chain = umtxq_hash(key); 232 umtxq_lock(key); 233 head = &umtxq_chains[chain].uc_queue; 234 LIST_FOREACH(uq, head, uq_next) { 235 if (umtx_key_match(&uq->uq_key, key)) { 236 blocked = uq->uq_thread; 237 umtxq_remove(uq); 238 break; 239 } 240 } 241 umtxq_unlock(key); 242 if (blocked != NULL) 243 wakeup(blocked); 244 } 245 246 static void 247 umtxq_broadcast(struct umtx_key *key) 248 { 249 struct umtx_q *uq, *next; 250 struct umtx_head *head; 251 struct thread *blocked; 252 int chain; 253 254 chain = umtxq_hash(key); 255 umtxq_lock(key); 256 head = &umtxq_chains[chain].uc_queue; 257 for (uq = LIST_FIRST(head); uq != NULL; uq = next) { 258 next = LIST_NEXT(uq, uq_next); 259 if (umtx_key_match(&uq->uq_key, key)) { 260 blocked = uq->uq_thread; 261 umtxq_remove(uq); 262 wakeup(blocked); 263 } 264 uq = next; 265 } 266 umtxq_unlock(key); 267 } 268 269 static inline int 270 umtxq_sleep(struct thread *td, struct umtx_key *key, int priority, 271 const char *wmesg, int timo) 272 { 273 int error; 274 int chain = umtxq_hash(key); 275 276 error = msleep(td, umtxq_mtx(chain), priority, wmesg, timo); 277 return (error); 278 } 279 280 static int 281 umtx_key_get(struct thread *td, struct umtx *umtx, struct umtx_key *key) 282 { 283 #if defined(UMTX_DYNAMIC_SHARED) || defined(UMTX_STATIC_SHARED) 284 vm_map_t map; 285 vm_map_entry_t entry; 286 vm_pindex_t pindex; 287 vm_prot_t prot; 288 boolean_t wired; 289 290 map = &td->td_proc->p_vmspace->vm_map; 291 if (vm_map_lookup(&map, (vm_offset_t)umtx, VM_PROT_WRITE, 292 &entry, &key->info.shared.object, &pindex, &prot, 293 &wired) != KERN_SUCCESS) { 294 return EFAULT; 295 } 296 #endif 297 298 #if defined(UMTX_DYNAMIC_SHARED) 299 key->type = UMTX_SHARED; 300 key->info.shared.offset = entry->offset + entry->start - 301 (vm_offset_t)umtx; 302 /* 303 * Add object reference, if we don't do this, a buggy application 304 * deallocates the object, the object will be reused by other 305 * applications, then unlock will wake wrong thread. 306 */ 307 vm_object_reference(key->info.shared.object); 308 vm_map_lookup_done(map, entry); 309 #elif defined(UMTX_STATIC_SHARED) 310 if (VM_INHERIT_SHARE == entry->inheritance) { 311 key->type = UMTX_SHARED; 312 key->info.shared.offset = entry->offset + entry->start - 313 (vm_offset_t)umtx; 314 vm_object_reference(key->info.shared.object); 315 } else { 316 key->type = UMTX_PRIVATE; 317 key->info.private.umtx = umtx; 318 key->info.private.pid = td->td_proc->p_pid; 319 } 320 vm_map_lookup_done(map, entry); 321 #else 322 key->type = UMTX_PRIVATE; 323 key->info.private.umtx = umtx; 324 key->info.private.pid = td->td_proc->p_pid; 325 #endif 326 return (0); 327 } 328 329 static inline void 330 umtx_key_release(struct umtx_key *key) 331 { 332 if (key->type == UMTX_SHARED) 333 vm_object_deallocate(key->info.shared.object); 334 } 335 336 static inline int 337 umtxq_queue_me(struct thread *td, struct umtx *umtx, struct umtx_q *uq) 338 { 339 int error; 340 341 if ((error = umtx_key_get(td, umtx, &uq->uq_key)) != 0) 342 return (error); 343 344 uq->uq_addr = (vm_offset_t)umtx; 345 uq->uq_thread = td; 346 umtxq_lock(&uq->uq_key); 347 umtxq_insert(uq); 348 umtxq_unlock(&uq->uq_key); 349 return (0); 350 } 351 352 #if defined(UMTX_DYNAMIC_SHARED) 353 static void 354 fork_handler(void *arg, struct proc *p1, struct proc *p2, int flags) 355 { 356 vm_map_t map; 357 vm_map_entry_t entry; 358 vm_object_t object; 359 vm_pindex_t pindex; 360 vm_prot_t prot; 361 boolean_t wired; 362 struct umtx_key key; 363 LIST_HEAD(, umtx_q) workq; 364 struct umtx_q *uq; 365 struct thread *td; 366 int onq; 367 368 LIST_INIT(&workq); 369 370 /* Collect threads waiting on umtxq */ 371 PROC_LOCK(p1); 372 FOREACH_THREAD_IN_PROC(p1, td) { 373 if (td->td_flags & TDF_UMTXQ) { 374 uq = td->td_umtxq; 375 if (uq) 376 LIST_INSERT_HEAD(&workq, uq, uq_rqnext); 377 } 378 } 379 PROC_UNLOCK(p1); 380 381 LIST_FOREACH(uq, &workq, uq_rqnext) { 382 map = &p1->p_vmspace->vm_map; 383 if (vm_map_lookup(&map, uq->uq_addr, VM_PROT_WRITE, 384 &entry, &object, &pindex, &prot, &wired) != KERN_SUCCESS) { 385 continue; 386 } 387 key.type = UMTX_SHARED; 388 key.info.shared.object = object; 389 key.info.shared.offset = entry->offset + entry->start - 390 uq->uq_addr; 391 if (umtx_key_match(&key, &uq->uq_key)) { 392 vm_map_lookup_done(map, entry); 393 continue; 394 } 395 396 umtxq_lock(&uq->uq_key); 397 if (uq->uq_thread->td_flags & TDF_UMTXQ) { 398 umtxq_remove(uq); 399 onq = 1; 400 } else 401 onq = 0; 402 umtxq_unlock(&uq->uq_key); 403 if (onq) { 404 vm_object_deallocate(uq->uq_key.info.shared.object); 405 uq->uq_key = key; 406 umtxq_lock(&uq->uq_key); 407 umtxq_insert(uq); 408 umtxq_unlock(&uq->uq_key); 409 vm_object_reference(uq->uq_key.info.shared.object); 410 } 411 vm_map_lookup_done(map, entry); 412 } 413 } 414 #endif 415 416 static int 417 _do_lock(struct thread *td, struct umtx *umtx, long id, int timo) 418 { 419 struct umtx_q uq; 420 intptr_t owner; 421 intptr_t old; 422 int error = 0; 423 424 /* 425 * Care must be exercised when dealing with umtx structure. It 426 * can fault on any access. 427 */ 428 429 for (;;) { 430 /* 431 * Try the uncontested case. This should be done in userland. 432 */ 433 owner = casuptr((intptr_t *)&umtx->u_owner, 434 UMTX_UNOWNED, id); 435 436 /* The acquire succeeded. */ 437 if (owner == UMTX_UNOWNED) 438 return (0); 439 440 /* The address was invalid. */ 441 if (owner == -1) 442 return (EFAULT); 443 444 /* If no one owns it but it is contested try to acquire it. */ 445 if (owner == UMTX_CONTESTED) { 446 owner = casuptr((intptr_t *)&umtx->u_owner, 447 UMTX_CONTESTED, id | UMTX_CONTESTED); 448 449 if (owner == UMTX_CONTESTED) 450 return (0); 451 452 /* The address was invalid. */ 453 if (owner == -1) 454 return (EFAULT); 455 456 /* If this failed the lock has changed, restart. */ 457 continue; 458 } 459 460 /* 461 * If we caught a signal, we have retried and now 462 * exit immediately. 463 */ 464 if (error || (error = umtxq_queue_me(td, umtx, &uq)) != 0) 465 return (error); 466 467 /* 468 * Set the contested bit so that a release in user space 469 * knows to use the system call for unlock. If this fails 470 * either some one else has acquired the lock or it has been 471 * released. 472 */ 473 old = casuptr((intptr_t *)&umtx->u_owner, owner, 474 owner | UMTX_CONTESTED); 475 476 /* The address was invalid. */ 477 if (old == -1) { 478 umtxq_lock(&uq.uq_key); 479 umtxq_remove(&uq); 480 umtxq_unlock(&uq.uq_key); 481 umtx_key_release(&uq.uq_key); 482 return (EFAULT); 483 } 484 485 /* 486 * We set the contested bit, sleep. Otherwise the lock changed 487 * and we need to retry or we lost a race to the thread 488 * unlocking the umtx. 489 */ 490 umtxq_lock(&uq.uq_key); 491 if (old == owner && (td->td_flags & TDF_UMTXQ)) { 492 error = umtxq_sleep(td, &uq.uq_key, 493 td->td_priority | PCATCH | PDROP, 494 "umtx", timo); 495 if (td->td_flags & TDF_UMTXQ) { 496 umtxq_lock(&uq.uq_key); 497 umtxq_remove(&uq); 498 umtxq_unlock(&uq.uq_key); 499 } 500 } else { 501 umtxq_remove(&uq); 502 umtxq_unlock(&uq.uq_key); 503 error = 0; 504 } 505 umtx_key_release(&uq.uq_key); 506 } 507 508 return (0); 509 } 510 511 static int 512 do_lock(struct thread *td, struct umtx *umtx, long id, 513 struct timespec *abstime) 514 { 515 struct timespec ts1, ts2; 516 struct timeval tv; 517 int timo, error; 518 519 if (abstime == NULL) { 520 error = _do_lock(td, umtx, id, 0); 521 } else { 522 for (;;) { 523 ts1 = *abstime; 524 getnanotime(&ts2); 525 timespecsub(&ts1, &ts2); 526 TIMESPEC_TO_TIMEVAL(&tv, &ts1); 527 if (tv.tv_sec < 0) { 528 error = EWOULDBLOCK; 529 break; 530 } 531 timo = tvtohz(&tv); 532 error = _do_lock(td, umtx, id, timo); 533 if (error != EWOULDBLOCK) { 534 if (error == ERESTART) 535 error = EINTR; 536 break; 537 } 538 } 539 } 540 return (error); 541 } 542 543 static int 544 do_unlock(struct thread *td, struct umtx *umtx, long id) 545 { 546 struct umtx_key key; 547 intptr_t owner; 548 intptr_t old; 549 int count, error; 550 551 /* 552 * Make sure we own this mtx. 553 * 554 * XXX Need a {fu,su}ptr this is not correct on arch where 555 * sizeof(intptr_t) != sizeof(long). 556 */ 557 if ((owner = fuword(&umtx->u_owner)) == -1) 558 return (EFAULT); 559 560 if ((owner & ~UMTX_CONTESTED) != id) 561 return (EPERM); 562 563 /* We should only ever be in here for contested locks */ 564 if ((owner & UMTX_CONTESTED) == 0) 565 return (EINVAL); 566 567 /* 568 * When unlocking the umtx, it must be marked as unowned if 569 * there is zero or one thread only waiting for it. 570 * Otherwise, it must be marked as contested. 571 */ 572 old = casuptr((intptr_t *)&umtx->u_owner, owner, UMTX_UNOWNED); 573 if (old == -1) 574 return (EFAULT); 575 if (old != owner) 576 return (EINVAL); 577 578 if ((error = umtx_key_get(td, umtx, &key)) != 0) 579 return (error); 580 581 /* 582 * At the point, a new thread can lock the umtx before we 583 * reach here, so contested bit will not be set, if there 584 * are two or more threads on wait queue, we should set 585 * contensted bit for them. 586 */ 587 count = umtxq_count(&key); 588 if (count <= 0) { 589 umtx_key_release(&key); 590 return (0); 591 } 592 593 /* 594 * If there is second thread waiting on umtx, set contested bit, 595 * if they are resumed before we reach here, it is harmless, 596 * just a bit unefficient. 597 */ 598 if (count > 1) { 599 owner = UMTX_UNOWNED; 600 for (;;) { 601 old = casuptr((intptr_t *)&umtx->u_owner, owner, 602 owner | UMTX_CONTESTED); 603 if (old == owner) 604 break; 605 if (old == -1) { 606 umtx_key_release(&key); 607 return (EFAULT); 608 } 609 owner = old; 610 } 611 /* 612 * Another thread locked the umtx before us, so don't bother 613 * to wake more threads, that thread will do it when it unlocks 614 * the umtx. 615 */ 616 if ((owner & ~UMTX_CONTESTED) != 0) { 617 umtx_key_release(&key); 618 return (0); 619 } 620 } 621 622 /* Wake blocked thread. */ 623 umtxq_signal(&key); 624 umtx_key_release(&key); 625 626 return (0); 627 } 628 629 static int 630 do_unlock_and_wait(struct thread *td, struct umtx *umtx, long id, void *uaddr, 631 struct timespec *abstime) 632 { 633 struct umtx_q uq; 634 intptr_t owner; 635 intptr_t old; 636 struct timespec ts1, ts2; 637 struct timeval tv; 638 int timo, error = 0; 639 640 if (umtx == uaddr) 641 return (EINVAL); 642 643 /* 644 * Make sure we own this mtx. 645 * 646 * XXX Need a {fu,su}ptr this is not correct on arch where 647 * sizeof(intptr_t) != sizeof(long). 648 */ 649 if ((owner = fuword(&umtx->u_owner)) == -1) 650 return (EFAULT); 651 652 if ((owner & ~UMTX_CONTESTED) != id) 653 return (EPERM); 654 655 if ((error = umtxq_queue_me(td, uaddr, &uq)) != 0) 656 return (error); 657 658 old = casuptr((intptr_t *)&umtx->u_owner, id, UMTX_UNOWNED); 659 if (old == -1) { 660 umtxq_lock(&uq.uq_key); 661 umtxq_remove(&uq); 662 umtxq_unlock(&uq.uq_key); 663 umtx_key_release(&uq.uq_key); 664 return (EFAULT); 665 } 666 if (old != id) { 667 error = do_unlock(td, umtx, id); 668 if (error) { 669 umtxq_lock(&uq.uq_key); 670 umtxq_remove(&uq); 671 umtxq_unlock(&uq.uq_key); 672 umtx_key_release(&uq.uq_key); 673 return (error); 674 } 675 } 676 if (abstime == NULL) { 677 umtxq_lock(&uq.uq_key); 678 if (td->td_flags & TDF_UMTXQ) 679 error = umtxq_sleep(td, &uq.uq_key, 680 td->td_priority | PCATCH, "ucond", 0); 681 umtxq_remove(&uq); 682 umtxq_unlock(&uq.uq_key); 683 if (error == ERESTART) 684 error = EINTR; 685 } else { 686 for (;;) { 687 ts1 = *abstime; 688 getnanotime(&ts2); 689 timespecsub(&ts1, &ts2); 690 TIMESPEC_TO_TIMEVAL(&tv, &ts1); 691 if (tv.tv_sec < 0) { 692 error = EWOULDBLOCK; 693 break; 694 } 695 timo = tvtohz(&tv); 696 umtxq_lock(&uq.uq_key); 697 if (td->td_flags & TDF_UMTXQ) { 698 error = umtxq_sleep(td, &uq.uq_key, 699 td->td_priority | PCATCH | PDROP, 700 "ucond", timo); 701 if (!(td->td_flags & TDF_UMTXQ)) { 702 error = 0; 703 break; 704 } 705 if (error != 0 && error != EWOULDBLOCK) { 706 if (error == ERESTART) 707 error = EINTR; 708 break; 709 } 710 } else { 711 umtxq_unlock(&uq.uq_key); 712 error = 0; 713 break; 714 } 715 } 716 if (td->td_flags & TDF_UMTXQ) { 717 umtxq_lock(&uq.uq_key); 718 umtxq_remove(&uq); 719 umtxq_unlock(&uq.uq_key); 720 } 721 } 722 umtx_key_release(&uq.uq_key); 723 return (error); 724 } 725 726 static int 727 do_wake(struct thread *td, void *uaddr, int broadcast) 728 { 729 struct umtx_key key; 730 int error; 731 732 if ((error = umtx_key_get(td, uaddr, &key)) != 0) 733 return (error); 734 if (!broadcast) 735 umtxq_signal(&key); 736 else 737 umtxq_broadcast(&key); 738 umtx_key_release(&key); 739 return (0); 740 } 741 742 int 743 _umtx_lock(struct thread *td, struct _umtx_lock_args *uap) 744 /* struct umtx *umtx */ 745 { 746 return _do_lock(td, uap->umtx, td->td_tid, 0); 747 } 748 749 int 750 _umtx_unlock(struct thread *td, struct _umtx_unlock_args *uap) 751 /* struct umtx *umtx */ 752 { 753 return do_unlock(td, uap->umtx, td->td_tid); 754 } 755 756 int 757 _umtx_op(struct thread *td, struct _umtx_op_args *uap) 758 { 759 struct timespec abstime; 760 struct timespec *ts; 761 int error; 762 763 switch(uap->op) { 764 case UMTX_OP_LOCK: 765 /* Allow a null timespec (wait forever). */ 766 if (uap->abstime == NULL) 767 ts = NULL; 768 else { 769 error = copyin(uap->abstime, &abstime, sizeof(abstime)); 770 if (error != 0) 771 return (error); 772 if (abstime.tv_nsec >= 1000000000 || 773 abstime.tv_nsec < 0) 774 return (EINVAL); 775 ts = &abstime; 776 } 777 return do_lock(td, uap->umtx, uap->id, ts); 778 case UMTX_OP_UNLOCK: 779 return do_unlock(td, uap->umtx, uap->id); 780 case UMTX_OP_UNLOCK_AND_WAIT: 781 /* Allow a null timespec (wait forever). */ 782 if (uap->abstime == NULL) 783 ts = NULL; 784 else { 785 error = copyin(uap->abstime, &abstime, sizeof(abstime)); 786 if (error != 0) 787 return (error); 788 if (abstime.tv_nsec >= 1000000000 || 789 abstime.tv_nsec < 0) 790 return (EINVAL); 791 ts = &abstime; 792 } 793 return do_unlock_and_wait(td, uap->umtx, uap->id, 794 uap->uaddr, ts); 795 case UMTX_OP_WAKE: 796 return do_wake(td, uap->uaddr, uap->id); 797 default: 798 return (EINVAL); 799 } 800 } 801