1/*
2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Scooter Morris at Genentech Inc.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * @(#)ufs_lockf.c 8.3 (Berkeley) 1/6/94
37 * $Id: kern_lockf.c,v 1.3 1994/10/25 11:27:51 davidg Exp $
38 */
39
40#include <sys/param.h>
41#include <sys/systm.h>
42#include <sys/kernel.h>
43#include <sys/file.h>
44#include <sys/proc.h>
45#include <sys/vnode.h>
46#include <sys/malloc.h>
47#include <sys/fcntl.h>
48
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 */
55int maxlockdepth = MAXDEPTH;
56
57#ifdef LOCKF_DEBUG
58int lockf_debug = 0;
59#endif
60
61#define NOLOCKF (struct lockf *)0
62#define SELF 0x1
63#define OTHERS 0x2
64
65/*
66 * Advisory record locking support
67 */
68int
69lf_advlock(ap, head, size)
70 struct vop_advlock_args /* {
71 struct vnode *a_vp;
72 caddr_t a_id;
73 int a_op;
74 struct flock *a_fl;
75 int a_flags;
76 } */ *ap;
77 struct lockf **head;
78 u_quad_t size;
79{
80 register struct flock *fl = ap->a_fl;
81 register struct lockf *lock;
82 off_t start, end;
83 int error;
84
85 /*
86 * Avoid the common case of unlocking when inode has no locks.
87 */
88 if (*head == (struct lockf *)0) {
89 if (ap->a_op != F_SETLK) {
90 fl->l_type = F_UNLCK;
91 return (0);
92 }
93 }
94 /*
95 * Convert the flock structure into a start and end.
96 */
97 switch (fl->l_whence) {
98
99 case SEEK_SET:
100 case SEEK_CUR:
101 /*
102 * Caller is responsible for adding any necessary offset
103 * when SEEK_CUR is used.
104 */
105 start = fl->l_start;
106 break;
107
108 case SEEK_END:
109 start = size + fl->l_start;
110 break;
111
112 default:
113 return (EINVAL);
114 }
115 if (start < 0)
116 return (EINVAL);
117 if (fl->l_len == 0)
118 end = -1;
119 else
120 end = start + fl->l_len - 1;
121 /*
122 * Create the lockf structure
123 */
124 MALLOC(lock, struct lockf *, sizeof *lock, M_LOCKF, M_WAITOK);
125 lock->lf_start = start;
126 lock->lf_end = end;
127 lock->lf_id = ap->a_id;
128 lock->lf_head = head;
129 lock->lf_type = fl->l_type;
130 lock->lf_next = (struct lockf *)0;
131 lock->lf_block = (struct lockf *)0;
132 lock->lf_flags = ap->a_flags;
133 /*
134 * Do the requested operation.
135 */
136 switch(ap->a_op) {
137 case F_SETLK:
138 return (lf_setlock(lock));
139
140 case F_UNLCK:
141 error = lf_clearlock(lock);
142 FREE(lock, M_LOCKF);
143 return (error);
144
145 case F_GETLK:
146 error = lf_getlock(lock, fl);
147 FREE(lock, M_LOCKF);
148 return (error);
149
150 default:
151 free(lock, M_LOCKF);
152 return (EINVAL);
153 }
154 /* NOTREACHED */
155}
156
157/*
158 * Set a byte-range lock.
159 */
160int
161lf_setlock(lock)
162 register struct lockf *lock;
163{
164 register struct lockf *block;
165 struct lockf **head = lock->lf_head;
166 struct lockf **prev, *overlap, *ltmp;
167 static char lockstr[] = "lockf";
168 int ovcase, priority, needtolink, error;
169
170#ifdef LOCKF_DEBUG
171 if (lockf_debug & 1)
172 lf_print("lf_setlock", lock);
173#endif /* LOCKF_DEBUG */
174
175 /*
176 * Set the priority
177 */
178 priority = PLOCK;
179 if (lock->lf_type == F_WRLCK)
180 priority += 4;
181 priority |= PCATCH;
182 /*
183 * Scan lock list for this file looking for locks that would block us.
184 */
185 while ((block = lf_getblock(lock))) {
186 /*
187 * Free the structure and return if nonblocking.
188 */
189 if ((lock->lf_flags & F_WAIT) == 0) {
190 FREE(lock, M_LOCKF);
191 return (EAGAIN);
192 }
193 /*
194 * We are blocked. Since flock style locks cover
195 * the whole file, there is no chance for deadlock.
196 * For byte-range locks we must check for deadlock.
197 *
198 * Deadlock detection is done by looking through the
199 * wait channels to see if there are any cycles that
200 * involve us. MAXDEPTH is set just to make sure we
201 * do not go off into neverland.
202 */
203 if ((lock->lf_flags & F_POSIX) &&
204 (block->lf_flags & F_POSIX)) {
205 register struct proc *wproc;
206 register struct lockf *waitblock;
207 int i = 0;
208
209 /* The block is waiting on something */
210 wproc = (struct proc *)block->lf_id;
211 while (wproc->p_wchan &&
212 (wproc->p_wmesg == lockstr) &&
213 (i++ < maxlockdepth)) {
214 waitblock = (struct lockf *)wproc->p_wchan;
215 /* Get the owner of the blocking lock */
216 waitblock = waitblock->lf_next;
217 if ((waitblock->lf_flags & F_POSIX) == 0)
218 break;
219 wproc = (struct proc *)waitblock->lf_id;
220 if (wproc == (struct proc *)lock->lf_id) {
221 free(lock, M_LOCKF);
222 return (EDEADLK);
223 }
224 }
225 }
226 /*
227 * For flock type locks, we must first remove
228 * any shared locks that we hold before we sleep
229 * waiting for an exclusive lock.
230 */
231 if ((lock->lf_flags & F_FLOCK) &&
232 lock->lf_type == F_WRLCK) {
233 lock->lf_type = F_UNLCK;
234 (void) lf_clearlock(lock);
235 lock->lf_type = F_WRLCK;
236 }
237 /*
238 * Add our lock to the blocked list and sleep until we're free.
239 * Remember who blocked us (for deadlock detection).
240 */
241 lock->lf_next = block;
242 lf_addblock(block, lock);
243#ifdef LOCKF_DEBUG
244 if (lockf_debug & 1) {
245 lf_print("lf_setlock: blocking on", block);
246 lf_printlist("lf_setlock", block);
247 }
248#endif /* LOCKF_DEBUG */
249 if ((error = tsleep((caddr_t)lock, priority, lockstr, 0))) {
250 /*
251 * Delete ourselves from the waiting to lock list.
252 */
253 for (block = lock->lf_next;
254 block != NOLOCKF;
255 block = block->lf_block) {
256 if (block->lf_block != lock)
257 continue;
258 block->lf_block = block->lf_block->lf_block;
259 break;
260 }
261 /*
262 * If we did not find ourselves on the list, but
263 * are still linked onto a lock list, then something
264 * is very wrong.
265 */
266 if (block == NOLOCKF && lock->lf_next != NOLOCKF)
267 panic("lf_setlock: lost lock");
268 free(lock, M_LOCKF);
269 return (error);
270 }
271 }
272 /*
273 * No blocks!! Add the lock. Note that we will
274 * downgrade or upgrade any overlapping locks this
275 * process already owns.
276 *
277 * Skip over locks owned by other processes.
278 * Handle any locks that overlap and are owned by ourselves.
279 */
280 prev = head;
281 block = *head;
282 needtolink = 1;
283 for (;;) {
284 ovcase = lf_findoverlap(block, lock, SELF, &prev, &overlap);
285 if (ovcase)
286 block = overlap->lf_next;
287 /*
288 * Six cases:
289 * 0) no overlap
290 * 1) overlap == lock
291 * 2) overlap contains lock
292 * 3) lock contains overlap
293 * 4) overlap starts before lock
294 * 5) overlap ends after lock
295 */
296 switch (ovcase) {
297 case 0: /* no overlap */
298 if (needtolink) {
299 *prev = lock;
300 lock->lf_next = overlap;
301 }
302 break;
303
304 case 1: /* overlap == lock */
305 /*
306 * If downgrading lock, others may be
307 * able to acquire it.
308 */
309 if (lock->lf_type == F_RDLCK &&
310 overlap->lf_type == F_WRLCK)
311 lf_wakelock(overlap);
312 overlap->lf_type = lock->lf_type;
313 FREE(lock, M_LOCKF);
314 lock = overlap; /* for debug output below */
315 break;
316
317 case 2: /* overlap contains lock */
318 /*
319 * Check for common starting point and different types.
320 */
321 if (overlap->lf_type == lock->lf_type) {
322 free(lock, M_LOCKF);
323 lock = overlap; /* for debug output below */
324 break;
325 }
326 if (overlap->lf_start == lock->lf_start) {
327 *prev = lock;
328 lock->lf_next = overlap;
329 overlap->lf_start = lock->lf_end + 1;
330 } else
331 lf_split(overlap, lock);
332 lf_wakelock(overlap);
333 break;
334
335 case 3: /* lock contains overlap */
336 /*
337 * If downgrading lock, others may be able to
338 * acquire it, otherwise take the list.
339 */
340 if (lock->lf_type == F_RDLCK &&
341 overlap->lf_type == F_WRLCK) {
342 lf_wakelock(overlap);
343 } else {
344 ltmp = lock->lf_block;
345 lock->lf_block = overlap->lf_block;
346 lf_addblock(lock, ltmp);
347 }
348 /*
349 * Add the new lock if necessary and delete the overlap.
350 */
351 if (needtolink) {
352 *prev = lock;
353 lock->lf_next = overlap->lf_next;
354 prev = &lock->lf_next;
355 needtolink = 0;
356 } else
357 *prev = overlap->lf_next;
358 free(overlap, M_LOCKF);
359 continue;
360
361 case 4: /* overlap starts before lock */
362 /*
363 * Add lock after overlap on the list.
364 */
365 lock->lf_next = overlap->lf_next;
366 overlap->lf_next = lock;
367 overlap->lf_end = lock->lf_start - 1;
368 prev = &lock->lf_next;
369 lf_wakelock(overlap);
370 needtolink = 0;
371 continue;
372
373 case 5: /* overlap ends after lock */
374 /*
375 * Add the new lock before overlap.
376 */
377 if (needtolink) {
378 *prev = lock;
379 lock->lf_next = overlap;
380 }
381 overlap->lf_start = lock->lf_end + 1;
382 lf_wakelock(overlap);
383 break;
384 }
385 break;
386 }
387#ifdef LOCKF_DEBUG
388 if (lockf_debug & 1) {
389 lf_print("lf_setlock: got the lock", lock);
390 lf_printlist("lf_setlock", lock);
391 }
392#endif /* LOCKF_DEBUG */
393 return (0);
394}
395
396/*
397 * Remove a byte-range lock on an inode.
398 *
399 * Generally, find the lock (or an overlap to that lock)
400 * and remove it (or shrink it), then wakeup anyone we can.
401 */
402int
403lf_clearlock(unlock)
404 register struct lockf *unlock;
405{
406 struct lockf **head = unlock->lf_head;
407 register struct lockf *lf = *head;
408 struct lockf *overlap, **prev;
409 int ovcase;
410
411 if (lf == NOLOCKF)
412 return (0);
413#ifdef LOCKF_DEBUG
414 if (unlock->lf_type != F_UNLCK)
415 panic("lf_clearlock: bad type");
416 if (lockf_debug & 1)
417 lf_print("lf_clearlock", unlock);
418#endif /* LOCKF_DEBUG */
419 prev = head;
420 while ((ovcase = lf_findoverlap(lf, unlock, SELF, &prev, &overlap))) {
421 /*
422 * Wakeup the list of locks to be retried.
423 */
424 lf_wakelock(overlap);
425
426 switch (ovcase) {
427
428 case 1: /* overlap == lock */
429 *prev = overlap->lf_next;
430 FREE(overlap, M_LOCKF);
431 break;
432
433 case 2: /* overlap contains lock: split it */
434 if (overlap->lf_start == unlock->lf_start) {
435 overlap->lf_start = unlock->lf_end + 1;
436 break;
437 }
438 lf_split(overlap, unlock);
439 overlap->lf_next = unlock->lf_next;
440 break;
441
442 case 3: /* lock contains overlap */
443 *prev = overlap->lf_next;
444 lf = overlap->lf_next;
445 free(overlap, M_LOCKF);
446 continue;
447
448 case 4: /* overlap starts before lock */
449 overlap->lf_end = unlock->lf_start - 1;
450 prev = &overlap->lf_next;
451 lf = overlap->lf_next;
452 continue;
453
454 case 5: /* overlap ends after lock */
455 overlap->lf_start = unlock->lf_end + 1;
456 break;
457 }
458 break;
459 }
460#ifdef LOCKF_DEBUG
461 if (lockf_debug & 1)
462 lf_printlist("lf_clearlock", unlock);
463#endif /* LOCKF_DEBUG */
464 return (0);
465}
466
467/*
468 * Check whether there is a blocking lock,
469 * and if so return its process identifier.
470 */
471int
472lf_getlock(lock, fl)
473 register struct lockf *lock;
474 register struct flock *fl;
475{
476 register struct lockf *block;
477
478#ifdef LOCKF_DEBUG
479 if (lockf_debug & 1)
480 lf_print("lf_getlock", lock);
481#endif /* LOCKF_DEBUG */
482
483 if ((block = lf_getblock(lock))) {
484 fl->l_type = block->lf_type;
485 fl->l_whence = SEEK_SET;
486 fl->l_start = block->lf_start;
487 if (block->lf_end == -1)
488 fl->l_len = 0;
489 else
490 fl->l_len = block->lf_end - block->lf_start + 1;
491 if (block->lf_flags & F_POSIX)
492 fl->l_pid = ((struct proc *)(block->lf_id))->p_pid;
493 else
494 fl->l_pid = -1;
495 } else {
496 fl->l_type = F_UNLCK;
497 }
498 return (0);
499}
500
501/*
502 * Walk the list of locks for an inode and
503 * return the first blocking lock.
504 */
505struct lockf *
506lf_getblock(lock)
507 register struct lockf *lock;
508{
509 struct lockf **prev, *overlap, *lf = *(lock->lf_head);
510 int ovcase;
511
512 prev = lock->lf_head;
513 while ((ovcase = lf_findoverlap(lf, lock, OTHERS, &prev, &overlap))) {
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 */
535int
536lf_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 */
644void
645lf_addblock(blocklist, lock)
646 struct lockf *blocklist;
647 struct lockf *lock;
648{
649 register struct lockf *lf;
650
651 if (lock == NOLOCKF)
652 return;
653#ifdef LOCKF_DEBUG
654 if (lockf_debug & 2) {
655 lf_print("addblock: adding", lock);
656 lf_print("to blocked list of", blocklist);
657 }
658#endif /* LOCKF_DEBUG */
659 if ((lf = blocklist->lf_block) == NOLOCKF) {
660 blocklist->lf_block = lock;
661 return;
662 }
663 while (lf->lf_block != NOLOCKF)
664 lf = lf->lf_block;
665 lf->lf_block = lock;
666 return;
667}
668
669/*
670 * Split a lock and a contained region into
671 * two or three locks as necessary.
672 */
673void
674lf_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 */
720void
721lf_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 */
745void
746lf_print(tag, lock)
747 char *tag;
748 register struct lockf *lock;
749{
750
751 printf("%s: lock 0x%lx 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 0x%x\n", lock->lf_block);
766 else
767 printf("\n");
768}
769
770void
771lf_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 0x%lx 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 0x%x\n", lf->lf_block);
794 else
795 printf("\n");
796 }
797}
798#endif /* LOCKF_DEBUG */