Commit | Line | Data |
---|---|---|
626862a9 WJ |
1 | /* |
2 | * Copyright (c) 1982, 1986, 1989 Regents of the University of California. | |
3 | * 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 7.7 (Berkeley) 7/2/91 | |
37 | */ | |
38 | ||
39 | #include "param.h" | |
40 | #include "systm.h" | |
41 | #include "kernel.h" | |
42 | #include "file.h" | |
43 | #include "proc.h" | |
44 | #include "vnode.h" | |
45 | #include "malloc.h" | |
46 | #include "fcntl.h" | |
47 | ||
48 | #include "lockf.h" | |
49 | #include "quota.h" | |
50 | #include "inode.h" | |
51 | ||
52 | /* | |
53 | * This variable controls the maximum number of processes that will | |
54 | * be checked in doing deadlock detection. | |
55 | */ | |
56 | int maxlockdepth = MAXDEPTH; | |
57 | ||
58 | #ifdef LOCKF_DEBUG | |
59 | int lockf_debug = 0; | |
60 | #endif /* LOCKF_DEBUG */ | |
61 | ||
62 | #define NOLOCKF (struct lockf *)0 | |
63 | #define SELF 0x1 | |
64 | #define OTHERS 0x2 | |
65 | ||
66 | /* | |
67 | * Set a byte-range lock. | |
68 | */ | |
69 | lf_setlock(lock) | |
70 | register struct lockf *lock; | |
71 | { | |
72 | register struct lockf *block; | |
73 | struct inode *ip = lock->lf_inode; | |
74 | struct lockf **prev, *overlap, *ltmp; | |
75 | static char lockstr[] = "lockf"; | |
76 | int ovcase, priority, needtolink, error; | |
77 | ||
78 | #ifdef LOCKF_DEBUG | |
79 | if (lockf_debug & 1) | |
80 | lf_print("lf_setlock", lock); | |
81 | #endif /* LOCKF_DEBUG */ | |
82 | ||
83 | /* | |
84 | * Set the priority | |
85 | */ | |
86 | priority = PLOCK; | |
87 | if (lock->lf_type == F_WRLCK) | |
88 | priority += 4; | |
89 | priority |= PCATCH; | |
90 | /* | |
91 | * Scan lock list for this file looking for locks that would block us. | |
92 | */ | |
93 | while (block = lf_getblock(lock)) { | |
94 | /* | |
95 | * Free the structure and return if nonblocking. | |
96 | */ | |
97 | if ((lock->lf_flags & F_WAIT) == 0) { | |
98 | FREE(lock, M_LOCKF); | |
99 | return (EAGAIN); | |
100 | } | |
101 | /* | |
102 | * We are blocked. Since flock style locks cover | |
103 | * the whole file, there is no chance for deadlock. | |
104 | * For byte-range locks we must check for deadlock. | |
105 | * | |
106 | * Deadlock detection is done by looking through the | |
107 | * wait channels to see if there are any cycles that | |
108 | * involve us. MAXDEPTH is set just to make sure we | |
109 | * do not go off into neverland. | |
110 | */ | |
111 | if ((lock->lf_flags & F_POSIX) && | |
112 | (block->lf_flags & F_POSIX)) { | |
113 | register struct proc *wproc; | |
114 | register struct lockf *waitblock; | |
115 | int i = 0; | |
116 | ||
117 | /* The block is waiting on something */ | |
118 | wproc = (struct proc *)block->lf_id; | |
119 | while (wproc->p_wchan && | |
120 | (wproc->p_wmesg == lockstr) && | |
121 | (i++ < maxlockdepth)) { | |
122 | waitblock = (struct lockf *)wproc->p_wchan; | |
123 | /* Get the owner of the blocking lock */ | |
124 | waitblock = waitblock->lf_next; | |
125 | if ((waitblock->lf_flags & F_POSIX) == 0) | |
126 | break; | |
127 | wproc = (struct proc *)waitblock->lf_id; | |
128 | if (wproc == (struct proc *)lock->lf_id) { | |
129 | free(lock, M_LOCKF); | |
130 | return (EDEADLK); | |
131 | } | |
132 | } | |
133 | } | |
134 | /* | |
135 | * For flock type locks, we must first remove | |
136 | * any shared locks that we hold before we sleep | |
137 | * waiting for an exclusive lock. | |
138 | */ | |
139 | if ((lock->lf_flags & F_FLOCK) && | |
140 | lock->lf_type == F_WRLCK) { | |
141 | lock->lf_type = F_UNLCK; | |
142 | (void) lf_clearlock(lock); | |
143 | lock->lf_type = F_WRLCK; | |
144 | } | |
145 | /* | |
146 | * Add our lock to the blocked list and sleep until we're free. | |
147 | * Remember who blocked us (for deadlock detection). | |
148 | */ | |
149 | lock->lf_next = block; | |
150 | lf_addblock(block, lock); | |
151 | #ifdef LOCKF_DEBUG | |
152 | if (lockf_debug & 1) { | |
153 | lf_print("lf_setlock: blocking on", block); | |
154 | lf_printlist("lf_setlock", block); | |
155 | } | |
156 | #endif /* LOCKF_DEBUG */ | |
157 | if (error = tsleep((caddr_t)lock, priority, lockstr, 0)) { | |
158 | free(lock, M_LOCKF); | |
159 | return (error); | |
160 | } | |
161 | } | |
162 | /* | |
163 | * No blocks!! Add the lock. Note that we will | |
164 | * downgrade or upgrade any overlapping locks this | |
165 | * process already owns. | |
166 | * | |
167 | * Skip over locks owned by other processes. | |
168 | * Handle any locks that overlap and are owned by ourselves. | |
169 | */ | |
170 | prev = &ip->i_lockf; | |
171 | block = ip->i_lockf; | |
172 | needtolink = 1; | |
173 | for (;;) { | |
174 | if (ovcase = lf_findoverlap(block, lock, SELF, &prev, &overlap)) | |
175 | block = overlap->lf_next; | |
176 | /* | |
177 | * Six cases: | |
178 | * 0) no overlap | |
179 | * 1) overlap == lock | |
180 | * 2) overlap contains lock | |
181 | * 3) lock contains overlap | |
182 | * 4) overlap starts before lock | |
183 | * 5) overlap ends after lock | |
184 | */ | |
185 | switch (ovcase) { | |
186 | case 0: /* no overlap */ | |
187 | if (needtolink) { | |
188 | *prev = lock; | |
189 | lock->lf_next = overlap; | |
190 | } | |
191 | break; | |
192 | ||
193 | case 1: /* overlap == lock */ | |
194 | /* | |
195 | * If downgrading lock, others may be | |
196 | * able to acquire it. | |
197 | */ | |
198 | if (lock->lf_type == F_RDLCK && | |
199 | overlap->lf_type == F_WRLCK) | |
200 | lf_wakelock(overlap); | |
201 | overlap->lf_type = lock->lf_type; | |
202 | FREE(lock, M_LOCKF); | |
203 | lock = overlap; /* for debug output below */ | |
204 | break; | |
205 | ||
206 | case 2: /* overlap contains lock */ | |
207 | /* | |
208 | * Check for common starting point and different types. | |
209 | */ | |
210 | if (overlap->lf_type == lock->lf_type) { | |
211 | free(lock, M_LOCKF); | |
212 | lock = overlap; /* for debug output below */ | |
213 | break; | |
214 | } | |
215 | if (overlap->lf_start == lock->lf_start) { | |
216 | *prev = lock; | |
217 | lock->lf_next = overlap; | |
218 | overlap->lf_start = lock->lf_end + 1; | |
219 | } else | |
220 | lf_split(overlap, lock); | |
221 | lf_wakelock(overlap); | |
222 | break; | |
223 | ||
224 | case 3: /* lock contains overlap */ | |
225 | /* | |
226 | * If downgrading lock, others may be able to | |
227 | * acquire it, otherwise take the list. | |
228 | */ | |
229 | if (lock->lf_type == F_RDLCK && | |
230 | overlap->lf_type == F_WRLCK) { | |
231 | lf_wakelock(overlap); | |
232 | } else { | |
233 | ltmp = lock->lf_block; | |
234 | lock->lf_block = overlap->lf_block; | |
235 | lf_addblock(lock, ltmp); | |
236 | } | |
237 | /* | |
238 | * Add the new lock if necessary and delete the overlap. | |
239 | */ | |
240 | if (needtolink) { | |
241 | *prev = lock; | |
242 | lock->lf_next = overlap->lf_next; | |
243 | prev = &lock->lf_next; | |
244 | needtolink = 0; | |
245 | } else | |
246 | *prev = overlap->lf_next; | |
247 | free(overlap, M_LOCKF); | |
248 | continue; | |
249 | ||
250 | case 4: /* overlap starts before lock */ | |
251 | /* | |
252 | * Add lock after overlap on the list. | |
253 | */ | |
254 | lock->lf_next = overlap->lf_next; | |
255 | overlap->lf_next = lock; | |
256 | overlap->lf_end = lock->lf_start - 1; | |
257 | prev = &lock->lf_next; | |
258 | lf_wakelock(overlap); | |
259 | needtolink = 0; | |
260 | continue; | |
261 | ||
262 | case 5: /* overlap ends after lock */ | |
263 | /* | |
264 | * Add the new lock before overlap. | |
265 | */ | |
266 | if (needtolink) { | |
267 | *prev = lock; | |
268 | lock->lf_next = overlap; | |
269 | } | |
270 | overlap->lf_start = lock->lf_end + 1; | |
271 | lf_wakelock(overlap); | |
272 | break; | |
273 | } | |
274 | break; | |
275 | } | |
276 | #ifdef LOCKF_DEBUG | |
277 | if (lockf_debug & 1) { | |
278 | lf_print("lf_setlock: got the lock", lock); | |
279 | lf_printlist("lf_setlock", lock); | |
280 | } | |
281 | #endif /* LOCKF_DEBUG */ | |
282 | return (0); | |
283 | } | |
284 | ||
285 | /* | |
286 | * Remove a byte-range lock on an inode. | |
287 | * | |
288 | * Generally, find the lock (or an overlap to that lock) | |
289 | * and remove it (or shrink it), then wakeup anyone we can. | |
290 | */ | |
291 | lf_clearlock(unlock) | |
292 | register struct lockf *unlock; | |
293 | { | |
294 | struct inode *ip = unlock->lf_inode; | |
295 | register struct lockf *lf = ip->i_lockf; | |
296 | struct lockf *overlap, **prev; | |
297 | int ovcase; | |
298 | ||
299 | if (lf == NOLOCKF) | |
300 | return (0); | |
301 | #ifdef LOCKF_DEBUG | |
302 | if (unlock->lf_type != F_UNLCK) | |
303 | panic("lf_clearlock: bad type"); | |
304 | if (lockf_debug & 1) | |
305 | lf_print("lf_clearlock", unlock); | |
306 | #endif /* LOCKF_DEBUG */ | |
307 | prev = &ip->i_lockf; | |
308 | while (ovcase = lf_findoverlap(lf, unlock, SELF, &prev, &overlap)) { | |
309 | /* | |
310 | * Wakeup the list of locks to be retried. | |
311 | */ | |
312 | lf_wakelock(overlap); | |
313 | ||
314 | switch (ovcase) { | |
315 | ||
316 | case 1: /* overlap == lock */ | |
317 | *prev = overlap->lf_next; | |
318 | FREE(overlap, M_LOCKF); | |
319 | break; | |
320 | ||
321 | case 2: /* overlap contains lock: split it */ | |
322 | if (overlap->lf_start == unlock->lf_start) { | |
323 | overlap->lf_start = unlock->lf_end + 1; | |
324 | break; | |
325 | } | |
326 | lf_split(overlap, unlock); | |
327 | overlap->lf_next = unlock->lf_next; | |
328 | break; | |
329 | ||
330 | case 3: /* lock contains overlap */ | |
331 | *prev = overlap->lf_next; | |
332 | lf = overlap->lf_next; | |
333 | free(overlap, M_LOCKF); | |
334 | continue; | |
335 | ||
336 | case 4: /* overlap starts before lock */ | |
337 | overlap->lf_end = unlock->lf_start - 1; | |
338 | prev = &overlap->lf_next; | |
339 | lf = overlap->lf_next; | |
340 | continue; | |
341 | ||
342 | case 5: /* overlap ends after lock */ | |
343 | overlap->lf_start = unlock->lf_end + 1; | |
344 | break; | |
345 | } | |
346 | break; | |
347 | } | |
348 | #ifdef LOCKF_DEBUG | |
349 | if (lockf_debug & 1) | |
350 | lf_printlist("lf_clearlock", unlock); | |
351 | #endif /* LOCKF_DEBUG */ | |
352 | return (0); | |
353 | } | |
354 | ||
355 | /* | |
356 | * Check whether there is a blocking lock, | |
357 | * and if so return its process identifier. | |
358 | */ | |
359 | lf_getlock(lock, fl) | |
360 | register struct lockf *lock; | |
361 | register struct flock *fl; | |
362 | { | |
363 | register struct lockf *block; | |
364 | off_t start, end; | |
365 | ||
366 | #ifdef LOCKF_DEBUG | |
367 | if (lockf_debug & 1) | |
368 | lf_print("lf_getlock", lock); | |
369 | #endif /* LOCKF_DEBUG */ | |
370 | ||
371 | if (block = lf_getblock(lock)) { | |
372 | fl->l_type = block->lf_type; | |
373 | fl->l_whence = SEEK_SET; | |
374 | fl->l_start = block->lf_start; | |
375 | if (block->lf_end == -1) | |
376 | fl->l_len = 0; | |
377 | else | |
378 | fl->l_len = block->lf_end - block->lf_start + 1; | |
379 | if (block->lf_flags & F_POSIX) | |
380 | fl->l_pid = ((struct proc *)(block->lf_id))->p_pid; | |
381 | else | |
382 | fl->l_pid = -1; | |
383 | } else { | |
384 | fl->l_type = F_UNLCK; | |
385 | } | |
386 | return (0); | |
387 | } | |
388 | ||
389 | /* | |
390 | * Walk the list of locks for an inode and | |
391 | * return the first blocking lock. | |
392 | */ | |
393 | struct lockf * | |
394 | lf_getblock(lock) | |
395 | register struct lockf *lock; | |
396 | { | |
397 | struct lockf **prev, *overlap, *lf = lock->lf_inode->i_lockf; | |
398 | int ovcase; | |
399 | ||
400 | prev = &lock->lf_inode->i_lockf; | |
401 | while (ovcase = lf_findoverlap(lf, lock, OTHERS, &prev, &overlap)) { | |
402 | /* | |
403 | * We've found an overlap, see if it blocks us | |
404 | */ | |
405 | if ((lock->lf_type == F_WRLCK || overlap->lf_type == F_WRLCK)) | |
406 | return (overlap); | |
407 | /* | |
408 | * Nope, point to the next one on the list and | |
409 | * see if it blocks us | |
410 | */ | |
411 | lf = overlap->lf_next; | |
412 | } | |
413 | return (NOLOCKF); | |
414 | } | |
415 | ||
416 | /* | |
417 | * Walk the list of locks for an inode to | |
418 | * find an overlapping lock (if any). | |
419 | * | |
420 | * NOTE: this returns only the FIRST overlapping lock. There | |
421 | * may be more than one. | |
422 | */ | |
423 | lf_findoverlap(lf, lock, type, prev, overlap) | |
424 | register struct lockf *lf; | |
425 | struct lockf *lock; | |
426 | int type; | |
427 | struct lockf ***prev; | |
428 | struct lockf **overlap; | |
429 | { | |
430 | off_t start, end; | |
431 | ||
432 | *overlap = lf; | |
433 | if (lf == NOLOCKF) | |
434 | return (0); | |
435 | #ifdef LOCKF_DEBUG | |
436 | if (lockf_debug & 2) | |
437 | lf_print("lf_findoverlap: looking for overlap in", lock); | |
438 | #endif /* LOCKF_DEBUG */ | |
439 | start = lock->lf_start; | |
440 | end = lock->lf_end; | |
441 | while (lf != NOLOCKF) { | |
442 | if (((type & SELF) && lf->lf_id != lock->lf_id) || | |
443 | ((type & OTHERS) && lf->lf_id == lock->lf_id)) { | |
444 | *prev = &lf->lf_next; | |
445 | *overlap = lf = lf->lf_next; | |
446 | continue; | |
447 | } | |
448 | #ifdef LOCKF_DEBUG | |
449 | if (lockf_debug & 2) | |
450 | lf_print("\tchecking", lf); | |
451 | #endif /* LOCKF_DEBUG */ | |
452 | /* | |
453 | * OK, check for overlap | |
454 | * | |
455 | * Six cases: | |
456 | * 0) no overlap | |
457 | * 1) overlap == lock | |
458 | * 2) overlap contains lock | |
459 | * 3) lock contains overlap | |
460 | * 4) overlap starts before lock | |
461 | * 5) overlap ends after lock | |
462 | */ | |
463 | if ((lf->lf_end != -1 && start > lf->lf_end) || | |
464 | (end != -1 && lf->lf_start > end)) { | |
465 | /* Case 0 */ | |
466 | #ifdef LOCKF_DEBUG | |
467 | if (lockf_debug & 2) | |
468 | printf("no overlap\n"); | |
469 | #endif /* LOCKF_DEBUG */ | |
470 | if ((type & SELF) && end != -1 && lf->lf_start > end) | |
471 | return (0); | |
472 | *prev = &lf->lf_next; | |
473 | *overlap = lf = lf->lf_next; | |
474 | continue; | |
475 | } | |
476 | if ((lf->lf_start == start) && (lf->lf_end == end)) { | |
477 | /* Case 1 */ | |
478 | #ifdef LOCKF_DEBUG | |
479 | if (lockf_debug & 2) | |
480 | printf("overlap == lock\n"); | |
481 | #endif /* LOCKF_DEBUG */ | |
482 | return (1); | |
483 | } | |
484 | if ((lf->lf_start <= start) && | |
485 | (end != -1) && | |
486 | ((lf->lf_end >= end) || (lf->lf_end == -1))) { | |
487 | /* Case 2 */ | |
488 | #ifdef LOCKF_DEBUG | |
489 | if (lockf_debug & 2) | |
490 | printf("overlap contains lock\n"); | |
491 | #endif /* LOCKF_DEBUG */ | |
492 | return (2); | |
493 | } | |
494 | if (start <= lf->lf_start && | |
495 | (end == -1 || | |
496 | (lf->lf_end != -1 && end >= lf->lf_end))) { | |
497 | /* Case 3 */ | |
498 | #ifdef LOCKF_DEBUG | |
499 | if (lockf_debug & 2) | |
500 | printf("lock contains overlap\n"); | |
501 | #endif /* LOCKF_DEBUG */ | |
502 | return (3); | |
503 | } | |
504 | if ((lf->lf_start < start) && | |
505 | ((lf->lf_end >= start) || (lf->lf_end == -1))) { | |
506 | /* Case 4 */ | |
507 | #ifdef LOCKF_DEBUG | |
508 | if (lockf_debug & 2) | |
509 | printf("overlap starts before lock\n"); | |
510 | #endif /* LOCKF_DEBUG */ | |
511 | return (4); | |
512 | } | |
513 | if ((lf->lf_start > start) && | |
514 | (end != -1) && | |
515 | ((lf->lf_end > end) || (lf->lf_end == -1))) { | |
516 | /* Case 5 */ | |
517 | #ifdef LOCKF_DEBUG | |
518 | if (lockf_debug & 2) | |
519 | printf("overlap ends after lock\n"); | |
520 | #endif /* LOCKF_DEBUG */ | |
521 | return (5); | |
522 | } | |
523 | panic("lf_findoverlap: default"); | |
524 | } | |
525 | return (0); | |
526 | } | |
527 | ||
528 | /* | |
529 | * Add a lock to the end of the blocked list. | |
530 | */ | |
531 | lf_addblock(lock, blocked) | |
532 | struct lockf *lock; | |
533 | struct lockf *blocked; | |
534 | { | |
535 | register struct lockf *lf; | |
536 | ||
537 | if (blocked == NOLOCKF) | |
538 | return; | |
539 | #ifdef LOCKF_DEBUG | |
540 | if (lockf_debug & 2) { | |
541 | lf_print("addblock: adding", blocked); | |
542 | lf_print("to blocked list of", lock); | |
543 | } | |
544 | #endif /* LOCKF_DEBUG */ | |
545 | if ((lf = lock->lf_block) == NOLOCKF) { | |
546 | lock->lf_block = blocked; | |
547 | return; | |
548 | } | |
549 | while (lf->lf_block != NOLOCKF) | |
550 | lf = lf->lf_block; | |
551 | lf->lf_block = blocked; | |
552 | return; | |
553 | } | |
554 | ||
555 | /* | |
556 | * Split a lock and a contained region into | |
557 | * two or three locks as necessary. | |
558 | */ | |
559 | lf_split(lock1, lock2) | |
560 | register struct lockf *lock1; | |
561 | register struct lockf *lock2; | |
562 | { | |
563 | register struct lockf *splitlock; | |
564 | ||
565 | #ifdef LOCKF_DEBUG | |
566 | if (lockf_debug & 2) { | |
567 | lf_print("lf_split", lock1); | |
568 | lf_print("splitting from", lock2); | |
569 | } | |
570 | #endif /* LOCKF_DEBUG */ | |
571 | /* | |
572 | * Check to see if spliting into only two pieces. | |
573 | */ | |
574 | if (lock1->lf_start == lock2->lf_start) { | |
575 | lock1->lf_start = lock2->lf_end + 1; | |
576 | lock2->lf_next = lock1; | |
577 | return; | |
578 | } | |
579 | if (lock1->lf_end == lock2->lf_end) { | |
580 | lock1->lf_end = lock2->lf_start - 1; | |
581 | lock2->lf_next = lock1->lf_next; | |
582 | lock1->lf_next = lock2; | |
583 | return; | |
584 | } | |
585 | /* | |
586 | * Make a new lock consisting of the last part of | |
587 | * the encompassing lock | |
588 | */ | |
589 | MALLOC(splitlock, struct lockf *, sizeof *splitlock, M_LOCKF, M_WAITOK); | |
590 | bcopy((caddr_t)lock1, (caddr_t)splitlock, sizeof *splitlock); | |
591 | splitlock->lf_start = lock2->lf_end + 1; | |
592 | splitlock->lf_block = NOLOCKF; | |
593 | lock1->lf_end = lock2->lf_start - 1; | |
594 | /* | |
595 | * OK, now link it in | |
596 | */ | |
597 | splitlock->lf_next = lock1->lf_next; | |
598 | lock2->lf_next = splitlock; | |
599 | lock1->lf_next = lock2; | |
600 | } | |
601 | ||
602 | /* | |
603 | * Wakeup a blocklist | |
604 | */ | |
605 | lf_wakelock(listhead) | |
606 | struct lockf *listhead; | |
607 | { | |
608 | register struct lockf *blocklist, *wakelock; | |
609 | ||
610 | blocklist = listhead->lf_block; | |
611 | listhead->lf_block = NOLOCKF; | |
612 | while (blocklist != NOLOCKF) { | |
613 | wakelock = blocklist; | |
614 | blocklist = blocklist->lf_block; | |
615 | wakelock->lf_block = NOLOCKF; | |
616 | wakelock->lf_next = NOLOCKF; | |
617 | #ifdef LOCKF_DEBUG | |
618 | if (lockf_debug & 2) | |
619 | lf_print("lf_wakelock: awakening", wakelock); | |
620 | #endif /* LOCKF_DEBUG */ | |
621 | wakeup((caddr_t)wakelock); | |
622 | } | |
623 | } | |
624 | ||
625 | #ifdef LOCKF_DEBUG | |
626 | /* | |
627 | * Print out a lock. | |
628 | */ | |
629 | lf_print(tag, lock) | |
630 | char *tag; | |
631 | register struct lockf *lock; | |
632 | { | |
633 | ||
634 | printf("%s: lock 0x%lx for ", tag, lock); | |
635 | if (lock->lf_flags & F_POSIX) | |
636 | printf("proc %d", ((struct proc *)(lock->lf_id))->p_pid); | |
637 | else | |
638 | printf("id 0x%x", lock->lf_id); | |
639 | printf(" in ino %d on dev <%d, %d>, %s, start %d, end %d", | |
640 | lock->lf_inode->i_number, | |
641 | major(lock->lf_inode->i_dev), | |
642 | minor(lock->lf_inode->i_dev), | |
643 | lock->lf_type == F_RDLCK ? "shared" : | |
644 | lock->lf_type == F_WRLCK ? "exclusive" : | |
645 | lock->lf_type == F_UNLCK ? "unlock" : | |
646 | "unknown", lock->lf_start, lock->lf_end); | |
647 | if (lock->lf_block) | |
648 | printf(" block 0x%x\n", lock->lf_block); | |
649 | else | |
650 | printf("\n"); | |
651 | } | |
652 | ||
653 | lf_printlist(tag, lock) | |
654 | char *tag; | |
655 | struct lockf *lock; | |
656 | { | |
657 | register struct lockf *lf; | |
658 | ||
659 | printf("%s: Lock list for ino %d on dev <%d, %d>:\n", | |
660 | tag, lock->lf_inode->i_number, | |
661 | major(lock->lf_inode->i_dev), | |
662 | minor(lock->lf_inode->i_dev)); | |
663 | for (lf = lock->lf_inode->i_lockf; lf; lf = lf->lf_next) { | |
664 | printf("\tlock 0x%lx for ", lf); | |
665 | if (lf->lf_flags & F_POSIX) | |
666 | printf("proc %d", ((struct proc *)(lf->lf_id))->p_pid); | |
667 | else | |
668 | printf("id 0x%x", lf->lf_id); | |
669 | printf(", %s, start %d, end %d", | |
670 | lf->lf_type == F_RDLCK ? "shared" : | |
671 | lf->lf_type == F_WRLCK ? "exclusive" : | |
672 | lf->lf_type == F_UNLCK ? "unlock" : | |
673 | "unknown", lf->lf_start, lf->lf_end); | |
674 | if (lf->lf_block) | |
675 | printf(" block 0x%x\n", lf->lf_block); | |
676 | else | |
677 | printf("\n"); | |
678 | } | |
679 | } | |
680 | #endif /* LOCKF_DEBUG */ |