vfs_lockf.c revision 1.7
1 /* $NetBSD: vfs_lockf.c,v 1.7 1996/02/04 02:18:21 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Scooter Morris at Genentech Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)ufs_lockf.c 8.3 (Berkeley) 1/6/94 39 */ 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/file.h> 45 #include <sys/proc.h> 46 #include <sys/vnode.h> 47 #include <sys/malloc.h> 48 #include <sys/fcntl.h> 49 #include <sys/lockf.h> 50 51 /* 52 * This variable controls the maximum number of processes that will 53 * be checked in doing deadlock detection. 54 */ 55 int maxlockdepth = MAXDEPTH; 56 57 #ifdef LOCKF_DEBUG 58 int lockf_debug = 0; 59 #endif 60 61 #define NOLOCKF (struct lockf *)0 62 #define SELF 0x1 63 #define OTHERS 0x2 64 65 /* 66 * Do an advisory lock operation. 67 */ 68 int 69 lf_advlock(head, size, id, op, fl, flags) 70 struct lockf **head; 71 off_t size; 72 caddr_t id; 73 int op; 74 register struct flock *fl; 75 int flags; 76 { 77 register struct lockf *lock; 78 off_t start, end; 79 int error; 80 81 /* 82 * Avoid the common case of unlocking when inode has no locks. 83 */ 84 if (*head == (struct lockf *)0) { 85 if (op != F_SETLK) { 86 fl->l_type = F_UNLCK; 87 return (0); 88 } 89 } 90 /* 91 * Convert the flock structure into a start and end. 92 */ 93 switch (fl->l_whence) { 94 95 case SEEK_SET: 96 case SEEK_CUR: 97 /* 98 * Caller is responsible for adding any necessary offset 99 * when SEEK_CUR is used. 100 */ 101 start = fl->l_start; 102 break; 103 104 case SEEK_END: 105 start = size + fl->l_start; 106 break; 107 108 default: 109 return (EINVAL); 110 } 111 if (start < 0) 112 return (EINVAL); 113 if (fl->l_len == 0) 114 end = -1; 115 else 116 end = start + fl->l_len - 1; 117 /* 118 * Create the lockf structure. 119 */ 120 MALLOC(lock, struct lockf *, sizeof *lock, M_LOCKF, M_WAITOK); 121 lock->lf_start = start; 122 lock->lf_end = end; 123 lock->lf_id = id; 124 lock->lf_head = head; 125 lock->lf_type = fl->l_type; 126 lock->lf_next = (struct lockf *)0; 127 lock->lf_block = (struct lockf *)0; 128 lock->lf_flags = flags; 129 /* 130 * Do the requested operation. 131 */ 132 switch (op) { 133 134 case F_SETLK: 135 return (lf_setlock(lock)); 136 137 case F_UNLCK: 138 error = lf_clearlock(lock); 139 FREE(lock, M_LOCKF); 140 return (error); 141 142 case F_GETLK: 143 error = lf_getlock(lock, fl); 144 FREE(lock, M_LOCKF); 145 return (error); 146 147 default: 148 FREE(lock, M_LOCKF); 149 return (EINVAL); 150 } 151 /* NOTREACHED */ 152 } 153 154 /* 155 * Set a byte-range lock. 156 */ 157 int 158 lf_setlock(lock) 159 register struct lockf *lock; 160 { 161 register struct lockf *block; 162 struct lockf **head = lock->lf_head; 163 struct lockf **prev, *overlap, *ltmp; 164 static char lockstr[] = "lockf"; 165 int ovcase, priority, needtolink, error; 166 167 #ifdef LOCKF_DEBUG 168 if (lockf_debug & 1) 169 lf_print("lf_setlock", lock); 170 #endif /* LOCKF_DEBUG */ 171 172 /* 173 * Set the priority 174 */ 175 priority = PLOCK; 176 if (lock->lf_type == F_WRLCK) 177 priority += 4; 178 priority |= PCATCH; 179 /* 180 * Scan lock list for this file looking for locks that would block us. 181 */ 182 while ((block = lf_getblock(lock)) != NULL) { 183 /* 184 * Free the structure and return if nonblocking. 185 */ 186 if ((lock->lf_flags & F_WAIT) == 0) { 187 FREE(lock, M_LOCKF); 188 return (EAGAIN); 189 } 190 /* 191 * We are blocked. Since flock style locks cover 192 * the whole file, there is no chance for deadlock. 193 * For byte-range locks we must check for deadlock. 194 * 195 * Deadlock detection is done by looking through the 196 * wait channels to see if there are any cycles that 197 * involve us. MAXDEPTH is set just to make sure we 198 * do not go off into neverland. 199 */ 200 if ((lock->lf_flags & F_POSIX) && 201 (block->lf_flags & F_POSIX)) { 202 register struct proc *wproc; 203 register struct lockf *waitblock; 204 int i = 0; 205 206 /* The block is waiting on something */ 207 wproc = (struct proc *)block->lf_id; 208 while (wproc->p_wchan && 209 (wproc->p_wmesg == lockstr) && 210 (i++ < maxlockdepth)) { 211 waitblock = (struct lockf *)wproc->p_wchan; 212 /* Get the owner of the blocking lock */ 213 waitblock = waitblock->lf_next; 214 if ((waitblock->lf_flags & F_POSIX) == 0) 215 break; 216 wproc = (struct proc *)waitblock->lf_id; 217 if (wproc == (struct proc *)lock->lf_id) { 218 free(lock, M_LOCKF); 219 return (EDEADLK); 220 } 221 } 222 } 223 /* 224 * For flock type locks, we must first remove 225 * any shared locks that we hold before we sleep 226 * waiting for an exclusive lock. 227 */ 228 if ((lock->lf_flags & F_FLOCK) && 229 lock->lf_type == F_WRLCK) { 230 lock->lf_type = F_UNLCK; 231 (void) lf_clearlock(lock); 232 lock->lf_type = F_WRLCK; 233 } 234 /* 235 * Add our lock to the blocked list and sleep until we're free. 236 * Remember who blocked us (for deadlock detection). 237 */ 238 lock->lf_next = block; 239 lf_addblock(block, lock); 240 #ifdef LOCKF_DEBUG 241 if (lockf_debug & 1) { 242 lf_print("lf_setlock: blocking on", block); 243 lf_printlist("lf_setlock", block); 244 } 245 #endif /* LOCKF_DEBUG */ 246 error = tsleep((caddr_t)lock, priority, lockstr, 0); 247 if (error) { 248 /* 249 * Delete ourselves from the waiting to lock list. 250 */ 251 for (block = lock->lf_next; 252 block != NOLOCKF; 253 block = block->lf_block) { 254 if (block->lf_block != lock) 255 continue; 256 block->lf_block = block->lf_block->lf_block; 257 break; 258 } 259 /* 260 * If we did not find ourselves on the list, but 261 * are still linked onto a lock list, then something 262 * is very wrong. 263 */ 264 if (block == NOLOCKF && lock->lf_next != NOLOCKF) 265 panic("lf_setlock: lost lock"); 266 free(lock, M_LOCKF); 267 return (error); 268 } 269 } 270 /* 271 * No blocks!! Add the lock. Note that we will 272 * downgrade or upgrade any overlapping locks this 273 * process already owns. 274 * 275 * Skip over locks owned by other processes. 276 * Handle any locks that overlap and are owned by ourselves. 277 */ 278 prev = head; 279 block = *head; 280 needtolink = 1; 281 for (;;) { 282 ovcase = lf_findoverlap(block, lock, SELF, &prev, &overlap); 283 if (ovcase) 284 block = overlap->lf_next; 285 /* 286 * Six cases: 287 * 0) no overlap 288 * 1) overlap == lock 289 * 2) overlap contains lock 290 * 3) lock contains overlap 291 * 4) overlap starts before lock 292 * 5) overlap ends after lock 293 */ 294 switch (ovcase) { 295 case 0: /* no overlap */ 296 if (needtolink) { 297 *prev = lock; 298 lock->lf_next = overlap; 299 } 300 break; 301 302 case 1: /* overlap == lock */ 303 /* 304 * If downgrading lock, others may be 305 * able to acquire it. 306 */ 307 if (lock->lf_type == F_RDLCK && 308 overlap->lf_type == F_WRLCK) 309 lf_wakelock(overlap); 310 overlap->lf_type = lock->lf_type; 311 FREE(lock, M_LOCKF); 312 lock = overlap; /* for debug output below */ 313 break; 314 315 case 2: /* overlap contains lock */ 316 /* 317 * Check for common starting point and different types. 318 */ 319 if (overlap->lf_type == lock->lf_type) { 320 free(lock, M_LOCKF); 321 lock = overlap; /* for debug output below */ 322 break; 323 } 324 if (overlap->lf_start == lock->lf_start) { 325 *prev = lock; 326 lock->lf_next = overlap; 327 overlap->lf_start = lock->lf_end + 1; 328 } else 329 lf_split(overlap, lock); 330 lf_wakelock(overlap); 331 break; 332 333 case 3: /* lock contains overlap */ 334 /* 335 * If downgrading lock, others may be able to 336 * acquire it, otherwise take the list. 337 */ 338 if (lock->lf_type == F_RDLCK && 339 overlap->lf_type == F_WRLCK) { 340 lf_wakelock(overlap); 341 } else { 342 ltmp = lock->lf_block; 343 lock->lf_block = overlap->lf_block; 344 lf_addblock(lock, ltmp); 345 } 346 /* 347 * Add the new lock if necessary and delete the overlap. 348 */ 349 if (needtolink) { 350 *prev = lock; 351 lock->lf_next = overlap->lf_next; 352 prev = &lock->lf_next; 353 needtolink = 0; 354 } else 355 *prev = overlap->lf_next; 356 free(overlap, M_LOCKF); 357 continue; 358 359 case 4: /* overlap starts before lock */ 360 /* 361 * Add lock after overlap on the list. 362 */ 363 lock->lf_next = overlap->lf_next; 364 overlap->lf_next = lock; 365 overlap->lf_end = lock->lf_start - 1; 366 prev = &lock->lf_next; 367 lf_wakelock(overlap); 368 needtolink = 0; 369 continue; 370 371 case 5: /* overlap ends after lock */ 372 /* 373 * Add the new lock before overlap. 374 */ 375 if (needtolink) { 376 *prev = lock; 377 lock->lf_next = overlap; 378 } 379 overlap->lf_start = lock->lf_end + 1; 380 lf_wakelock(overlap); 381 break; 382 } 383 break; 384 } 385 #ifdef LOCKF_DEBUG 386 if (lockf_debug & 1) { 387 lf_print("lf_setlock: got the lock", lock); 388 lf_printlist("lf_setlock", lock); 389 } 390 #endif /* LOCKF_DEBUG */ 391 return (0); 392 } 393 394 /* 395 * Remove a byte-range lock on an inode. 396 * 397 * Generally, find the lock (or an overlap to that lock) 398 * and remove it (or shrink it), then wakeup anyone we can. 399 */ 400 int 401 lf_clearlock(unlock) 402 register struct lockf *unlock; 403 { 404 struct lockf **head = unlock->lf_head; 405 register struct lockf *lf = *head; 406 struct lockf *overlap, **prev; 407 int ovcase; 408 409 if (lf == NOLOCKF) 410 return (0); 411 #ifdef LOCKF_DEBUG 412 if (unlock->lf_type != F_UNLCK) 413 panic("lf_clearlock: bad type"); 414 if (lockf_debug & 1) 415 lf_print("lf_clearlock", unlock); 416 #endif /* LOCKF_DEBUG */ 417 prev = head; 418 while ((ovcase = lf_findoverlap(lf, unlock, SELF, 419 &prev, &overlap)) != 0) { 420 /* 421 * Wakeup the list of locks to be retried. 422 */ 423 lf_wakelock(overlap); 424 425 switch (ovcase) { 426 427 case 1: /* overlap == lock */ 428 *prev = overlap->lf_next; 429 FREE(overlap, M_LOCKF); 430 break; 431 432 case 2: /* overlap contains lock: split it */ 433 if (overlap->lf_start == unlock->lf_start) { 434 overlap->lf_start = unlock->lf_end + 1; 435 break; 436 } 437 lf_split(overlap, unlock); 438 overlap->lf_next = unlock->lf_next; 439 break; 440 441 case 3: /* lock contains overlap */ 442 *prev = overlap->lf_next; 443 lf = overlap->lf_next; 444 free(overlap, M_LOCKF); 445 continue; 446 447 case 4: /* overlap starts before lock */ 448 overlap->lf_end = unlock->lf_start - 1; 449 prev = &overlap->lf_next; 450 lf = overlap->lf_next; 451 continue; 452 453 case 5: /* overlap ends after lock */ 454 overlap->lf_start = unlock->lf_end + 1; 455 break; 456 } 457 break; 458 } 459 #ifdef LOCKF_DEBUG 460 if (lockf_debug & 1) 461 lf_printlist("lf_clearlock", unlock); 462 #endif /* LOCKF_DEBUG */ 463 return (0); 464 } 465 466 /* 467 * Check whether there is a blocking lock, 468 * and if so return its process identifier. 469 */ 470 int 471 lf_getlock(lock, fl) 472 register struct lockf *lock; 473 register struct flock *fl; 474 { 475 register struct lockf *block; 476 477 #ifdef LOCKF_DEBUG 478 if (lockf_debug & 1) 479 lf_print("lf_getlock", lock); 480 #endif /* LOCKF_DEBUG */ 481 482 if ((block = lf_getblock(lock)) != NULL) { 483 fl->l_type = block->lf_type; 484 fl->l_whence = SEEK_SET; 485 fl->l_start = block->lf_start; 486 if (block->lf_end == -1) 487 fl->l_len = 0; 488 else 489 fl->l_len = block->lf_end - block->lf_start + 1; 490 if (block->lf_flags & F_POSIX) 491 fl->l_pid = ((struct proc *)(block->lf_id))->p_pid; 492 else 493 fl->l_pid = -1; 494 } else { 495 fl->l_type = F_UNLCK; 496 } 497 return (0); 498 } 499 500 /* 501 * Walk the list of locks for an inode and 502 * return the first blocking lock. 503 */ 504 struct lockf * 505 lf_getblock(lock) 506 register struct lockf *lock; 507 { 508 struct lockf **prev, *overlap, *lf = *(lock->lf_head); 509 int ovcase; 510 511 prev = lock->lf_head; 512 while ((ovcase = lf_findoverlap(lf, lock, OTHERS, 513 &prev, &overlap)) != 0) { 514 /* 515 * We've found an overlap, see if it blocks us 516 */ 517 if ((lock->lf_type == F_WRLCK || overlap->lf_type == F_WRLCK)) 518 return (overlap); 519 /* 520 * Nope, point to the next one on the list and 521 * see if it blocks us 522 */ 523 lf = overlap->lf_next; 524 } 525 return (NOLOCKF); 526 } 527 528 /* 529 * Walk the list of locks for an inode to 530 * find an overlapping lock (if any). 531 * 532 * NOTE: this returns only the FIRST overlapping lock. There 533 * may be more than one. 534 */ 535 int 536 lf_findoverlap(lf, lock, type, prev, overlap) 537 register struct lockf *lf; 538 struct lockf *lock; 539 int type; 540 struct lockf ***prev; 541 struct lockf **overlap; 542 { 543 off_t start, end; 544 545 *overlap = lf; 546 if (lf == NOLOCKF) 547 return (0); 548 #ifdef LOCKF_DEBUG 549 if (lockf_debug & 2) 550 lf_print("lf_findoverlap: looking for overlap in", lock); 551 #endif /* LOCKF_DEBUG */ 552 start = lock->lf_start; 553 end = lock->lf_end; 554 while (lf != NOLOCKF) { 555 if (((type & SELF) && lf->lf_id != lock->lf_id) || 556 ((type & OTHERS) && lf->lf_id == lock->lf_id)) { 557 *prev = &lf->lf_next; 558 *overlap = lf = lf->lf_next; 559 continue; 560 } 561 #ifdef LOCKF_DEBUG 562 if (lockf_debug & 2) 563 lf_print("\tchecking", lf); 564 #endif /* LOCKF_DEBUG */ 565 /* 566 * OK, check for overlap 567 * 568 * Six cases: 569 * 0) no overlap 570 * 1) overlap == lock 571 * 2) overlap contains lock 572 * 3) lock contains overlap 573 * 4) overlap starts before lock 574 * 5) overlap ends after lock 575 */ 576 if ((lf->lf_end != -1 && start > lf->lf_end) || 577 (end != -1 && lf->lf_start > end)) { 578 /* Case 0 */ 579 #ifdef LOCKF_DEBUG 580 if (lockf_debug & 2) 581 printf("no overlap\n"); 582 #endif /* LOCKF_DEBUG */ 583 if ((type & SELF) && end != -1 && lf->lf_start > end) 584 return (0); 585 *prev = &lf->lf_next; 586 *overlap = lf = lf->lf_next; 587 continue; 588 } 589 if ((lf->lf_start == start) && (lf->lf_end == end)) { 590 /* Case 1 */ 591 #ifdef LOCKF_DEBUG 592 if (lockf_debug & 2) 593 printf("overlap == lock\n"); 594 #endif /* LOCKF_DEBUG */ 595 return (1); 596 } 597 if ((lf->lf_start <= start) && 598 (end != -1) && 599 ((lf->lf_end >= end) || (lf->lf_end == -1))) { 600 /* Case 2 */ 601 #ifdef LOCKF_DEBUG 602 if (lockf_debug & 2) 603 printf("overlap contains lock\n"); 604 #endif /* LOCKF_DEBUG */ 605 return (2); 606 } 607 if (start <= lf->lf_start && 608 (end == -1 || 609 (lf->lf_end != -1 && end >= lf->lf_end))) { 610 /* Case 3 */ 611 #ifdef LOCKF_DEBUG 612 if (lockf_debug & 2) 613 printf("lock contains overlap\n"); 614 #endif /* LOCKF_DEBUG */ 615 return (3); 616 } 617 if ((lf->lf_start < start) && 618 ((lf->lf_end >= start) || (lf->lf_end == -1))) { 619 /* Case 4 */ 620 #ifdef LOCKF_DEBUG 621 if (lockf_debug & 2) 622 printf("overlap starts before lock\n"); 623 #endif /* LOCKF_DEBUG */ 624 return (4); 625 } 626 if ((lf->lf_start > start) && 627 (end != -1) && 628 ((lf->lf_end > end) || (lf->lf_end == -1))) { 629 /* Case 5 */ 630 #ifdef LOCKF_DEBUG 631 if (lockf_debug & 2) 632 printf("overlap ends after lock\n"); 633 #endif /* LOCKF_DEBUG */ 634 return (5); 635 } 636 panic("lf_findoverlap: default"); 637 } 638 return (0); 639 } 640 641 /* 642 * Add a lock to the end of the blocked list. 643 */ 644 void 645 lf_addblock(lock, blocked) 646 struct lockf *lock; 647 struct lockf *blocked; 648 { 649 register struct lockf *lf; 650 651 if (blocked == NOLOCKF) 652 return; 653 #ifdef LOCKF_DEBUG 654 if (lockf_debug & 2) { 655 lf_print("addblock: adding", blocked); 656 lf_print("to blocked list of", lock); 657 } 658 #endif /* LOCKF_DEBUG */ 659 if ((lf = lock->lf_block) == NOLOCKF) { 660 lock->lf_block = blocked; 661 return; 662 } 663 while (lf->lf_block != NOLOCKF) 664 lf = lf->lf_block; 665 lf->lf_block = blocked; 666 return; 667 } 668 669 /* 670 * Split a lock and a contained region into 671 * two or three locks as necessary. 672 */ 673 void 674 lf_split(lock1, lock2) 675 register struct lockf *lock1; 676 register struct lockf *lock2; 677 { 678 register struct lockf *splitlock; 679 680 #ifdef LOCKF_DEBUG 681 if (lockf_debug & 2) { 682 lf_print("lf_split", lock1); 683 lf_print("splitting from", lock2); 684 } 685 #endif /* LOCKF_DEBUG */ 686 /* 687 * Check to see if spliting into only two pieces. 688 */ 689 if (lock1->lf_start == lock2->lf_start) { 690 lock1->lf_start = lock2->lf_end + 1; 691 lock2->lf_next = lock1; 692 return; 693 } 694 if (lock1->lf_end == lock2->lf_end) { 695 lock1->lf_end = lock2->lf_start - 1; 696 lock2->lf_next = lock1->lf_next; 697 lock1->lf_next = lock2; 698 return; 699 } 700 /* 701 * Make a new lock consisting of the last part of 702 * the encompassing lock 703 */ 704 MALLOC(splitlock, struct lockf *, sizeof *splitlock, M_LOCKF, M_WAITOK); 705 bcopy((caddr_t)lock1, (caddr_t)splitlock, sizeof *splitlock); 706 splitlock->lf_start = lock2->lf_end + 1; 707 splitlock->lf_block = NOLOCKF; 708 lock1->lf_end = lock2->lf_start - 1; 709 /* 710 * OK, now link it in 711 */ 712 splitlock->lf_next = lock1->lf_next; 713 lock2->lf_next = splitlock; 714 lock1->lf_next = lock2; 715 } 716 717 /* 718 * Wakeup a blocklist 719 */ 720 void 721 lf_wakelock(listhead) 722 struct lockf *listhead; 723 { 724 register struct lockf *blocklist, *wakelock; 725 726 blocklist = listhead->lf_block; 727 listhead->lf_block = NOLOCKF; 728 while (blocklist != NOLOCKF) { 729 wakelock = blocklist; 730 blocklist = blocklist->lf_block; 731 wakelock->lf_block = NOLOCKF; 732 wakelock->lf_next = NOLOCKF; 733 #ifdef LOCKF_DEBUG 734 if (lockf_debug & 2) 735 lf_print("lf_wakelock: awakening", wakelock); 736 #endif /* LOCKF_DEBUG */ 737 wakeup((caddr_t)wakelock); 738 } 739 } 740 741 #ifdef LOCKF_DEBUG 742 /* 743 * Print out a lock. 744 */ 745 void 746 lf_print(tag, lock) 747 char *tag; 748 register struct lockf *lock; 749 { 750 751 printf("%s: lock %p for ", tag, lock); 752 if (lock->lf_flags & F_POSIX) 753 printf("proc %d", ((struct proc *)(lock->lf_id))->p_pid); 754 else 755 printf("id 0x%x", lock->lf_id); 756 printf(" in ino %d on dev <%d, %d>, %s, start %d, end %d", 757 lock->lf_inode->i_number, 758 major(lock->lf_inode->i_dev), 759 minor(lock->lf_inode->i_dev), 760 lock->lf_type == F_RDLCK ? "shared" : 761 lock->lf_type == F_WRLCK ? "exclusive" : 762 lock->lf_type == F_UNLCK ? "unlock" : 763 "unknown", lock->lf_start, lock->lf_end); 764 if (lock->lf_block) 765 printf(" block %p\n", lock->lf_block); 766 else 767 printf("\n"); 768 } 769 770 void 771 lf_printlist(tag, lock) 772 char *tag; 773 struct lockf *lock; 774 { 775 register struct lockf *lf; 776 777 printf("%s: Lock list for ino %d on dev <%d, %d>:\n", 778 tag, lock->lf_inode->i_number, 779 major(lock->lf_inode->i_dev), 780 minor(lock->lf_inode->i_dev)); 781 for (lf = lock->lf_inode->i_lockf; lf; lf = lf->lf_next) { 782 printf("\tlock %p for ", lf); 783 if (lf->lf_flags & F_POSIX) 784 printf("proc %d", ((struct proc *)(lf->lf_id))->p_pid); 785 else 786 printf("id 0x%x", lf->lf_id); 787 printf(", %s, start %d, end %d", 788 lf->lf_type == F_RDLCK ? "shared" : 789 lf->lf_type == F_WRLCK ? "exclusive" : 790 lf->lf_type == F_UNLCK ? "unlock" : 791 "unknown", lf->lf_start, lf->lf_end); 792 if (lf->lf_block) 793 printf(" block %p\n", lf->lf_block); 794 else 795 printf("\n"); 796 } 797 } 798 #endif /* LOCKF_DEBUG */ 799
Indexes created Tue Sep 23 14:10:03 GMT 2025