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Merge CTDB-related fixes from samba-ctdb 3.0 branch (http://samba.org/~tridge/3_0...
[Samba.git] / source3 / locking / brlock.c
blob4191871bb1a200bedf84b35075d663cb1eab1f01
1 /*
2 Unix SMB/CIFS implementation.
3 byte range locking code
4 Updated to handle range splits/merges.
5
6 Copyright (C) Andrew Tridgell 1992-2000
7 Copyright (C) Jeremy Allison 1992-2000
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 */
22
23 /* This module implements a tdb based byte range locking service,
24 replacing the fcntl() based byte range locking previously
25 used. This allows us to provide the same semantics as NT */
26
27 #include "includes.h"
28
29 #undef DBGC_CLASS
30 #define DBGC_CLASS DBGC_LOCKING
31
32 #define ZERO_ZERO 0
33
34 /* The open brlock.tdb database. */
35
36 static struct db_context *brlock_db;
37
38 /****************************************************************************
39 Debug info at level 10 for lock struct.
40 ****************************************************************************/
41
42 static void print_lock_struct(unsigned int i, struct lock_struct *pls)
43 {
44 DEBUG(10,("[%u]: smbpid = %u, tid = %u, pid = %u, ",
45 i,
46 (unsigned int)pls->context.smbpid,
47 (unsigned int)pls->context.tid,
48 (unsigned int)procid_to_pid(&pls->context.pid) ));
49
50 DEBUG(10,("start = %.0f, size = %.0f, fnum = %d, %s %s\n",
51 (double)pls->start,
52 (double)pls->size,
53 pls->fnum,
54 lock_type_name(pls->lock_type),
55 lock_flav_name(pls->lock_flav) ));
56 }
57
58 /****************************************************************************
59 See if two locking contexts are equal.
60 ****************************************************************************/
61
62 bool brl_same_context(const struct lock_context *ctx1,
63 const struct lock_context *ctx2)
64 {
65 return (procid_equal(&ctx1->pid, &ctx2->pid) &&
66 (ctx1->smbpid == ctx2->smbpid) &&
67 (ctx1->tid == ctx2->tid));
68 }
69
70 /****************************************************************************
71 See if lck1 and lck2 overlap.
72 ****************************************************************************/
73
74 static bool brl_overlap(const struct lock_struct *lck1,
75 const struct lock_struct *lck2)
76 {
77 /* this extra check is not redundent - it copes with locks
78 that go beyond the end of 64 bit file space */
79 if (lck1->size != 0 &&
80 lck1->start == lck2->start &&
81 lck1->size == lck2->size) {
82 return True;
83 }
84
85 if (lck1->start >= (lck2->start+lck2->size) ||
86 lck2->start >= (lck1->start+lck1->size)) {
87 return False;
88 }
89 return True;
90 }
91
92 /****************************************************************************
93 See if lock2 can be added when lock1 is in place.
94 ****************************************************************************/
95
96 static bool brl_conflict(const struct lock_struct *lck1,
97 const struct lock_struct *lck2)
98 {
99 /* Ignore PENDING locks. */
100 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
101 return False;
102
103 /* Read locks never conflict. */
104 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
105 return False;
106 }
107
108 if (brl_same_context(&lck1->context, &lck2->context) &&
109 lck2->lock_type == READ_LOCK && lck1->fnum == lck2->fnum) {
110 return False;
111 }
112
113 return brl_overlap(lck1, lck2);
114 }
115
116 /****************************************************************************
117 See if lock2 can be added when lock1 is in place - when both locks are POSIX
118 flavour. POSIX locks ignore fnum - they only care about dev/ino which we
119 know already match.
120 ****************************************************************************/
121
122 static bool brl_conflict_posix(const struct lock_struct *lck1,
123 const struct lock_struct *lck2)
124 {
125 #if defined(DEVELOPER)
126 SMB_ASSERT(lck1->lock_flav == POSIX_LOCK);
127 SMB_ASSERT(lck2->lock_flav == POSIX_LOCK);
128 #endif
129
130 /* Ignore PENDING locks. */
131 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
132 return False;
133
134 /* Read locks never conflict. */
135 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
136 return False;
137 }
138
139 /* Locks on the same context con't conflict. Ignore fnum. */
140 if (brl_same_context(&lck1->context, &lck2->context)) {
141 return False;
142 }
143
144 /* One is read, the other write, or the context is different,
145 do they overlap ? */
146 return brl_overlap(lck1, lck2);
147 }
148
149 #if ZERO_ZERO
150 static bool brl_conflict1(const struct lock_struct *lck1,
151 const struct lock_struct *lck2)
152 {
153 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
154 return False;
155
156 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
157 return False;
158 }
159
160 if (brl_same_context(&lck1->context, &lck2->context) &&
161 lck2->lock_type == READ_LOCK && lck1->fnum == lck2->fnum) {
162 return False;
163 }
164
165 if (lck2->start == 0 && lck2->size == 0 && lck1->size != 0) {
166 return True;
167 }
168
169 if (lck1->start >= (lck2->start + lck2->size) ||
170 lck2->start >= (lck1->start + lck1->size)) {
171 return False;
172 }
173
174 return True;
175 }
176 #endif
177
178 /****************************************************************************
179 Check to see if this lock conflicts, but ignore our own locks on the
180 same fnum only. This is the read/write lock check code path.
181 This is never used in the POSIX lock case.
182 ****************************************************************************/
183
184 static bool brl_conflict_other(const struct lock_struct *lck1, const struct lock_struct *lck2)
185 {
186 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
187 return False;
188
189 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK)
190 return False;
191
192 /* POSIX flavour locks never conflict here - this is only called
193 in the read/write path. */
194
195 if (lck1->lock_flav == POSIX_LOCK && lck2->lock_flav == POSIX_LOCK)
196 return False;
197
198 /*
199 * Incoming WRITE locks conflict with existing READ locks even
200 * if the context is the same. JRA. See LOCKTEST7 in smbtorture.
201 */
202
203 if (!(lck2->lock_type == WRITE_LOCK && lck1->lock_type == READ_LOCK)) {
204 if (brl_same_context(&lck1->context, &lck2->context) &&
205 lck1->fnum == lck2->fnum)
206 return False;
207 }
208
209 return brl_overlap(lck1, lck2);
210 }
211
212 /****************************************************************************
213 Check if an unlock overlaps a pending lock.
214 ****************************************************************************/
215
216 static bool brl_pending_overlap(const struct lock_struct *lock, const struct lock_struct *pend_lock)
217 {
218 if ((lock->start <= pend_lock->start) && (lock->start + lock->size > pend_lock->start))
219 return True;
220 if ((lock->start >= pend_lock->start) && (lock->start <= pend_lock->start + pend_lock->size))
221 return True;
222 return False;
223 }
224
225 /****************************************************************************
226 Amazingly enough, w2k3 "remembers" whether the last lock failure on a fnum
227 is the same as this one and changes its error code. I wonder if any
228 app depends on this ?
229 ****************************************************************************/
230
231 static NTSTATUS brl_lock_failed(files_struct *fsp, const struct lock_struct *lock, bool blocking_lock)
232 {
233 if (lock->start >= 0xEF000000 && (lock->start >> 63) == 0) {
234 /* amazing the little things you learn with a test
235 suite. Locks beyond this offset (as a 64 bit
236 number!) always generate the conflict error code,
237 unless the top bit is set */
238 if (!blocking_lock) {
239 fsp->last_lock_failure = *lock;
240 }
241 return NT_STATUS_FILE_LOCK_CONFLICT;
242 }
243
244 if (procid_equal(&lock->context.pid, &fsp->last_lock_failure.context.pid) &&
245 lock->context.tid == fsp->last_lock_failure.context.tid &&
246 lock->fnum == fsp->last_lock_failure.fnum &&
247 lock->start == fsp->last_lock_failure.start) {
248 return NT_STATUS_FILE_LOCK_CONFLICT;
249 }
250
251 if (!blocking_lock) {
252 fsp->last_lock_failure = *lock;
253 }
254 return NT_STATUS_LOCK_NOT_GRANTED;
255 }
256
257 /****************************************************************************
258 Open up the brlock.tdb database.
259 ****************************************************************************/
260
261 void brl_init(bool read_only)
262 {
263 if (brlock_db) {
264 return;
265 }
266 brlock_db = db_open(NULL, lock_path("brlock.tdb"),
267 lp_open_files_db_hash_size(),
268 TDB_DEFAULT | TDB_CLEAR_IF_FIRST,
269 read_only?O_RDONLY:(O_RDWR|O_CREAT), 0644 );
270 if (!brlock_db) {
271 DEBUG(0,("Failed to open byte range locking database %s\n",
272 lock_path("brlock.tdb")));
273 return;
274 }
275 }
276
277 /****************************************************************************
278 Close down the brlock.tdb database.
279 ****************************************************************************/
280
281 void brl_shutdown(void)
282 {
283 TALLOC_FREE(brlock_db);
284 }
285
286 #if ZERO_ZERO
287 /****************************************************************************
288 Compare two locks for sorting.
289 ****************************************************************************/
290
291 static int lock_compare(const struct lock_struct *lck1,
292 const struct lock_struct *lck2)
293 {
294 if (lck1->start != lck2->start) {
295 return (lck1->start - lck2->start);
296 }
297 if (lck2->size != lck1->size) {
298 return ((int)lck1->size - (int)lck2->size);
299 }
300 return 0;
301 }
302 #endif
303
304 /****************************************************************************
305 Lock a range of bytes - Windows lock semantics.
306 ****************************************************************************/
307
308 static NTSTATUS brl_lock_windows(struct byte_range_lock *br_lck,
309 struct lock_struct *plock, bool blocking_lock)
310 {
311 unsigned int i;
312 files_struct *fsp = br_lck->fsp;
313 struct lock_struct *locks = br_lck->lock_data;
314
315 for (i=0; i < br_lck->num_locks; i++) {
316 /* Do any Windows or POSIX locks conflict ? */
317 if (brl_conflict(&locks[i], plock)) {
318 /* Remember who blocked us. */
319 plock->context.smbpid = locks[i].context.smbpid;
320 return brl_lock_failed(fsp,plock,blocking_lock);
321 }
322 #if ZERO_ZERO
323 if (plock->start == 0 && plock->size == 0 &&
324 locks[i].size == 0) {
325 break;
326 }
327 #endif
328 }
329
330 /* We can get the Windows lock, now see if it needs to
331 be mapped into a lower level POSIX one, and if so can
332 we get it ? */
333
334 if (!IS_PENDING_LOCK(plock->lock_type) && lp_posix_locking(fsp->conn->params)) {
335 int errno_ret;
336 if (!set_posix_lock_windows_flavour(fsp,
337 plock->start,
338 plock->size,
339 plock->lock_type,
340 &plock->context,
341 locks,
342 br_lck->num_locks,
343 &errno_ret)) {
344
345 /* We don't know who blocked us. */
346 plock->context.smbpid = 0xFFFFFFFF;
347
348 if (errno_ret == EACCES || errno_ret == EAGAIN) {
349 return NT_STATUS_FILE_LOCK_CONFLICT;
350 } else {
351 return map_nt_error_from_unix(errno);
352 }
353 }
354 }
355
356 /* no conflicts - add it to the list of locks */
357 locks = (struct lock_struct *)SMB_REALLOC(locks, (br_lck->num_locks + 1) * sizeof(*locks));
358 if (!locks) {
359 return NT_STATUS_NO_MEMORY;
360 }
361
362 memcpy(&locks[br_lck->num_locks], plock, sizeof(struct lock_struct));
363 br_lck->num_locks += 1;
364 br_lck->lock_data = locks;
365 br_lck->modified = True;
366
367 return NT_STATUS_OK;
368 }
369
370 /****************************************************************************
371 Cope with POSIX range splits and merges.
372 ****************************************************************************/
373
374 static unsigned int brlock_posix_split_merge(struct lock_struct *lck_arr, /* Output array. */
375 const struct lock_struct *ex, /* existing lock. */
376 const struct lock_struct *plock, /* proposed lock. */
377 bool *lock_was_added)
378 {
379 bool lock_types_differ = (ex->lock_type != plock->lock_type);
380
381 /* We can't merge non-conflicting locks on different context - ignore fnum. */
382
383 if (!brl_same_context(&ex->context, &plock->context)) {
384 /* Just copy. */
385 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
386 return 1;
387 }
388
389 /* We now know we have the same context. */
390
391 /* Did we overlap ? */
392
393 /*********************************************
394 +---------+
395 | ex |
396 +---------+
397 +-------+
398 | plock |
399 +-------+
400 OR....
401 +---------+
402 | ex |
403 +---------+
404 **********************************************/
405
406 if ( (ex->start > (plock->start + plock->size)) ||
407 (plock->start > (ex->start + ex->size))) {
408 /* No overlap with this lock - copy existing. */
409 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
410 return 1;
411 }
412
413 /*********************************************
414 +---------------------------+
415 | ex |
416 +---------------------------+
417 +---------------------------+
418 | plock | -> replace with plock.
419 +---------------------------+
420 **********************************************/
421
422 if ( (ex->start >= plock->start) &&
423 (ex->start + ex->size <= plock->start + plock->size) ) {
424 memcpy(&lck_arr[0], plock, sizeof(struct lock_struct));
425 *lock_was_added = True;
426 return 1;
427 }
428
429 /*********************************************
430 +-----------------------+
431 | ex |
432 +-----------------------+
433 +---------------+
434 | plock |
435 +---------------+
436 OR....
437 +-------+
438 | ex |
439 +-------+
440 +---------------+
441 | plock |
442 +---------------+
443
444 BECOMES....
445 +---------------+-------+
446 | plock | ex | - different lock types.
447 +---------------+-------+
448 OR.... (merge)
449 +-----------------------+
450 | ex | - same lock type.
451 +-----------------------+
452 **********************************************/
453
454 if ( (ex->start >= plock->start) &&
455 (ex->start <= plock->start + plock->size) &&
456 (ex->start + ex->size > plock->start + plock->size) ) {
457
458 *lock_was_added = True;
459
460 /* If the lock types are the same, we merge, if different, we
461 add the new lock before the old. */
462
463 if (lock_types_differ) {
464 /* Add new. */
465 memcpy(&lck_arr[0], plock, sizeof(struct lock_struct));
466 memcpy(&lck_arr[1], ex, sizeof(struct lock_struct));
467 /* Adjust existing start and size. */
468 lck_arr[1].start = plock->start + plock->size;
469 lck_arr[1].size = (ex->start + ex->size) - (plock->start + plock->size);
470 return 2;
471 } else {
472 /* Merge. */
473 memcpy(&lck_arr[0], plock, sizeof(struct lock_struct));
474 /* Set new start and size. */
475 lck_arr[0].start = plock->start;
476 lck_arr[0].size = (ex->start + ex->size) - plock->start;
477 return 1;
478 }
479 }
480
481 /*********************************************
482 +-----------------------+
483 | ex |
484 +-----------------------+
485 +---------------+
486 | plock |
487 +---------------+
488 OR....
489 +-------+
490 | ex |
491 +-------+
492 +---------------+
493 | plock |
494 +---------------+
495 BECOMES....
496 +-------+---------------+
497 | ex | plock | - different lock types
498 +-------+---------------+
499
500 OR.... (merge)
501 +-----------------------+
502 | ex | - same lock type.
503 +-----------------------+
504
505 **********************************************/
506
507 if ( (ex->start < plock->start) &&
508 (ex->start + ex->size >= plock->start) &&
509 (ex->start + ex->size <= plock->start + plock->size) ) {
510
511 *lock_was_added = True;
512
513 /* If the lock types are the same, we merge, if different, we
514 add the new lock after the old. */
515
516 if (lock_types_differ) {
517 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
518 memcpy(&lck_arr[1], plock, sizeof(struct lock_struct));
519 /* Adjust existing size. */
520 lck_arr[0].size = plock->start - ex->start;
521 return 2;
522 } else {
523 /* Merge. */
524 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
525 /* Adjust existing size. */
526 lck_arr[0].size = (plock->start + plock->size) - ex->start;
527 return 1;
528 }
529 }
530
531 /*********************************************
532 +---------------------------+
533 | ex |
534 +---------------------------+
535 +---------+
536 | plock |
537 +---------+
538 BECOMES.....
539 +-------+---------+---------+
540 | ex | plock | ex | - different lock types.
541 +-------+---------+---------+
542 OR
543 +---------------------------+
544 | ex | - same lock type.
545 +---------------------------+
546 **********************************************/
547
548 if ( (ex->start < plock->start) && (ex->start + ex->size > plock->start + plock->size) ) {
549 *lock_was_added = True;
550
551 if (lock_types_differ) {
552
553 /* We have to split ex into two locks here. */
554
555 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
556 memcpy(&lck_arr[1], plock, sizeof(struct lock_struct));
557 memcpy(&lck_arr[2], ex, sizeof(struct lock_struct));
558
559 /* Adjust first existing size. */
560 lck_arr[0].size = plock->start - ex->start;
561
562 /* Adjust second existing start and size. */
563 lck_arr[2].start = plock->start + plock->size;
564 lck_arr[2].size = (ex->start + ex->size) - (plock->start + plock->size);
565 return 3;
566 } else {
567 /* Just eat plock. */
568 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
569 return 1;
570 }
571 }
572
573 /* Never get here. */
574 smb_panic("brlock_posix_split_merge");
575 /* Notreached. */
576
577 /* Keep some compilers happy. */
578 return 0;
579 }
580
581 /****************************************************************************
582 Lock a range of bytes - POSIX lock semantics.
583 We must cope with range splits and merges.
584 ****************************************************************************/
585
586 static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
587 struct byte_range_lock *br_lck,
588 struct lock_struct *plock)
589 {
590 unsigned int i, count;
591 struct lock_struct *locks = br_lck->lock_data;
592 struct lock_struct *tp;
593 bool lock_was_added = False;
594 bool signal_pending_read = False;
595
596 /* No zero-zero locks for POSIX. */
597 if (plock->start == 0 && plock->size == 0) {
598 return NT_STATUS_INVALID_PARAMETER;
599 }
600
601 /* Don't allow 64-bit lock wrap. */
602 if (plock->start + plock->size < plock->start ||
603 plock->start + plock->size < plock->size) {
604 return NT_STATUS_INVALID_PARAMETER;
605 }
606
607 /* The worst case scenario here is we have to split an
608 existing POSIX lock range into two, and add our lock,
609 so we need at most 2 more entries. */
610
611 tp = SMB_MALLOC_ARRAY(struct lock_struct, (br_lck->num_locks + 2));
612 if (!tp) {
613 return NT_STATUS_NO_MEMORY;
614 }
615
616 count = 0;
617 for (i=0; i < br_lck->num_locks; i++) {
618 struct lock_struct *curr_lock = &locks[i];
619
620 /* If we have a pending read lock, a lock downgrade should
621 trigger a lock re-evaluation. */
622 if (curr_lock->lock_type == PENDING_READ_LOCK &&
623 brl_pending_overlap(plock, curr_lock)) {
624 signal_pending_read = True;
625 }
626
627 if (curr_lock->lock_flav == WINDOWS_LOCK) {
628 /* Do any Windows flavour locks conflict ? */
629 if (brl_conflict(curr_lock, plock)) {
630 /* No games with error messages. */
631 SAFE_FREE(tp);
632 /* Remember who blocked us. */
633 plock->context.smbpid = curr_lock->context.smbpid;
634 return NT_STATUS_FILE_LOCK_CONFLICT;
635 }
636 /* Just copy the Windows lock into the new array. */
637 memcpy(&tp[count], curr_lock, sizeof(struct lock_struct));
638 count++;
639 } else {
640 /* POSIX conflict semantics are different. */
641 if (brl_conflict_posix(curr_lock, plock)) {
642 /* Can't block ourselves with POSIX locks. */
643 /* No games with error messages. */
644 SAFE_FREE(tp);
645 /* Remember who blocked us. */
646 plock->context.smbpid = curr_lock->context.smbpid;
647 return NT_STATUS_FILE_LOCK_CONFLICT;
648 }
649
650 /* Work out overlaps. */
651 count += brlock_posix_split_merge(&tp[count], curr_lock, plock, &lock_was_added);
652 }
653 }
654
655 if (!lock_was_added) {
656 memcpy(&tp[count], plock, sizeof(struct lock_struct));
657 count++;
658 }
659
660 /* We can get the POSIX lock, now see if it needs to
661 be mapped into a lower level POSIX one, and if so can
662 we get it ? */
663
664 if (!IS_PENDING_LOCK(plock->lock_type) && lp_posix_locking(br_lck->fsp->conn->params)) {
665 int errno_ret;
666
667 /* The lower layer just needs to attempt to
668 get the system POSIX lock. We've weeded out
669 any conflicts above. */
670
671 if (!set_posix_lock_posix_flavour(br_lck->fsp,
672 plock->start,
673 plock->size,
674 plock->lock_type,
675 &errno_ret)) {
676
677 /* We don't know who blocked us. */
678 plock->context.smbpid = 0xFFFFFFFF;
679
680 if (errno_ret == EACCES || errno_ret == EAGAIN) {
681 SAFE_FREE(tp);
682 return NT_STATUS_FILE_LOCK_CONFLICT;
683 } else {
684 SAFE_FREE(tp);
685 return map_nt_error_from_unix(errno);
686 }
687 }
688 }
689
690 /* Realloc so we don't leak entries per lock call. */
691 tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
692 if (!tp) {
693 return NT_STATUS_NO_MEMORY;
694 }
695 br_lck->num_locks = count;
696 SAFE_FREE(br_lck->lock_data);
697 br_lck->lock_data = tp;
698 locks = tp;
699 br_lck->modified = True;
700
701 /* A successful downgrade from write to read lock can trigger a lock
702 re-evalutation where waiting readers can now proceed. */
703
704 if (signal_pending_read) {
705 /* Send unlock messages to any pending read waiters that overlap. */
706 for (i=0; i < br_lck->num_locks; i++) {
707 struct lock_struct *pend_lock = &locks[i];
708
709 /* Ignore non-pending locks. */
710 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
711 continue;
712 }
713
714 if (pend_lock->lock_type == PENDING_READ_LOCK &&
715 brl_pending_overlap(plock, pend_lock)) {
716 DEBUG(10,("brl_lock_posix: sending unlock message to pid %s\n",
717 procid_str_static(&pend_lock->context.pid )));
718
719 messaging_send(msg_ctx, pend_lock->context.pid,
720 MSG_SMB_UNLOCK, &data_blob_null);
721 }
722 }
723 }
724
725 return NT_STATUS_OK;
726 }
727
728 /****************************************************************************
729 Lock a range of bytes.
730 ****************************************************************************/
731
732 NTSTATUS brl_lock(struct messaging_context *msg_ctx,
733 struct byte_range_lock *br_lck,
734 uint32 smbpid,
735 struct server_id pid,
736 br_off start,
737 br_off size,
738 enum brl_type lock_type,
739 enum brl_flavour lock_flav,
740 bool blocking_lock,
741 uint32 *psmbpid)
742 {
743 NTSTATUS ret;
744 struct lock_struct lock;
745
746 #if !ZERO_ZERO
747 if (start == 0 && size == 0) {
748 DEBUG(0,("client sent 0/0 lock - please report this\n"));
749 }
750 #endif
751
752 lock.context.smbpid = smbpid;
753 lock.context.pid = pid;
754 lock.context.tid = br_lck->fsp->conn->cnum;
755 lock.start = start;
756 lock.size = size;
757 lock.fnum = br_lck->fsp->fnum;
758 lock.lock_type = lock_type;
759 lock.lock_flav = lock_flav;
760
761 if (lock_flav == WINDOWS_LOCK) {
762 ret = brl_lock_windows(br_lck, &lock, blocking_lock);
763 } else {
764 ret = brl_lock_posix(msg_ctx, br_lck, &lock);
765 }
766
767 #if ZERO_ZERO
768 /* sort the lock list */
769 qsort(br_lck->lock_data, (size_t)br_lck->num_locks, sizeof(lock), lock_compare);
770 #endif
771
772 /* If we're returning an error, return who blocked us. */
773 if (!NT_STATUS_IS_OK(ret) && psmbpid) {
774 *psmbpid = lock.context.smbpid;
775 }
776 return ret;
777 }
778
779 /****************************************************************************
780 Unlock a range of bytes - Windows semantics.
781 ****************************************************************************/
782
783 static bool brl_unlock_windows(struct messaging_context *msg_ctx,
784 struct byte_range_lock *br_lck,
785 const struct lock_struct *plock)
786 {
787 unsigned int i, j;
788 struct lock_struct *locks = br_lck->lock_data;
789 enum brl_type deleted_lock_type = READ_LOCK; /* shut the compiler up.... */
790
791 #if ZERO_ZERO
792 /* Delete write locks by preference... The lock list
793 is sorted in the zero zero case. */
794
795 for (i = 0; i < br_lck->num_locks; i++) {
796 struct lock_struct *lock = &locks[i];
797
798 if (lock->lock_type == WRITE_LOCK &&
799 brl_same_context(&lock->context, &plock->context) &&
800 lock->fnum == plock->fnum &&
801 lock->lock_flav == WINDOWS_LOCK &&
802 lock->start == plock->start &&
803 lock->size == plock->size) {
804
805 /* found it - delete it */
806 deleted_lock_type = lock->lock_type;
807 break;
808 }
809 }
810
811 if (i != br_lck->num_locks) {
812 /* We found it - don't search again. */
813 goto unlock_continue;
814 }
815 #endif
816
817 for (i = 0; i < br_lck->num_locks; i++) {
818 struct lock_struct *lock = &locks[i];
819
820 /* Only remove our own locks that match in start, size, and flavour. */
821 if (brl_same_context(&lock->context, &plock->context) &&
822 lock->fnum == plock->fnum &&
823 lock->lock_flav == WINDOWS_LOCK &&
824 lock->start == plock->start &&
825 lock->size == plock->size ) {
826 deleted_lock_type = lock->lock_type;
827 break;
828 }
829 }
830
831 if (i == br_lck->num_locks) {
832 /* we didn't find it */
833 return False;
834 }
835
836 #if ZERO_ZERO
837 unlock_continue:
838 #endif
839
840 /* Actually delete the lock. */
841 if (i < br_lck->num_locks - 1) {
842 memmove(&locks[i], &locks[i+1],
843 sizeof(*locks)*((br_lck->num_locks-1) - i));
844 }
845
846 br_lck->num_locks -= 1;
847 br_lck->modified = True;
848
849 /* Unlock the underlying POSIX regions. */
850 if(lp_posix_locking(br_lck->fsp->conn->params)) {
851 release_posix_lock_windows_flavour(br_lck->fsp,
852 plock->start,
853 plock->size,
854 deleted_lock_type,
855 &plock->context,
856 locks,
857 br_lck->num_locks);
858 }
859
860 /* Send unlock messages to any pending waiters that overlap. */
861 for (j=0; j < br_lck->num_locks; j++) {
862 struct lock_struct *pend_lock = &locks[j];
863
864 /* Ignore non-pending locks. */
865 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
866 continue;
867 }
868
869 /* We could send specific lock info here... */
870 if (brl_pending_overlap(plock, pend_lock)) {
871 DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
872 procid_str_static(&pend_lock->context.pid )));
873
874 messaging_send(msg_ctx, pend_lock->context.pid,
875 MSG_SMB_UNLOCK, &data_blob_null);
876 }
877 }
878
879 return True;
880 }
881
882 /****************************************************************************
883 Unlock a range of bytes - POSIX semantics.
884 ****************************************************************************/
885
886 static bool brl_unlock_posix(struct messaging_context *msg_ctx,
887 struct byte_range_lock *br_lck,
888 const struct lock_struct *plock)
889 {
890 unsigned int i, j, count;
891 struct lock_struct *tp;
892 struct lock_struct *locks = br_lck->lock_data;
893 bool overlap_found = False;
894
895 /* No zero-zero locks for POSIX. */
896 if (plock->start == 0 && plock->size == 0) {
897 return False;
898 }
899
900 /* Don't allow 64-bit lock wrap. */
901 if (plock->start + plock->size < plock->start ||
902 plock->start + plock->size < plock->size) {
903 DEBUG(10,("brl_unlock_posix: lock wrap\n"));
904 return False;
905 }
906
907 /* The worst case scenario here is we have to split an
908 existing POSIX lock range into two, so we need at most
909 1 more entry. */
910
911 tp = SMB_MALLOC_ARRAY(struct lock_struct, (br_lck->num_locks + 1));
912 if (!tp) {
913 DEBUG(10,("brl_unlock_posix: malloc fail\n"));
914 return False;
915 }
916
917 count = 0;
918 for (i = 0; i < br_lck->num_locks; i++) {
919 struct lock_struct *lock = &locks[i];
920 struct lock_struct tmp_lock[3];
921 bool lock_was_added = False;
922 unsigned int tmp_count;
923
924 /* Only remove our own locks - ignore fnum. */
925 if (IS_PENDING_LOCK(lock->lock_type) ||
926 !brl_same_context(&lock->context, &plock->context)) {
927 memcpy(&tp[count], lock, sizeof(struct lock_struct));
928 count++;
929 continue;
930 }
931
932 /* Work out overlaps. */
933 tmp_count = brlock_posix_split_merge(&tmp_lock[0], &locks[i], plock, &lock_was_added);
934
935 if (tmp_count == 1) {
936 /* Ether the locks didn't overlap, or the unlock completely
937 overlapped this lock. If it didn't overlap, then there's
938 no change in the locks. */
939 if (tmp_lock[0].lock_type != UNLOCK_LOCK) {
940 SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
941 /* No change in this lock. */
942 memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
943 count++;
944 } else {
945 SMB_ASSERT(tmp_lock[0].lock_type == UNLOCK_LOCK);
946 overlap_found = True;
947 }
948 continue;
949 } else if (tmp_count == 2) {
950 /* The unlock overlapped an existing lock. Copy the truncated
951 lock into the lock array. */
952 if (tmp_lock[0].lock_type != UNLOCK_LOCK) {
953 SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
954 SMB_ASSERT(tmp_lock[1].lock_type == UNLOCK_LOCK);
955 memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
956 if (tmp_lock[0].size != locks[i].size) {
957 overlap_found = True;
958 }
959 } else {
960 SMB_ASSERT(tmp_lock[0].lock_type == UNLOCK_LOCK);
961 SMB_ASSERT(tmp_lock[1].lock_type == locks[i].lock_type);
962 memcpy(&tp[count], &tmp_lock[1], sizeof(struct lock_struct));
963 if (tmp_lock[1].start != locks[i].start) {
964 overlap_found = True;
965 }
966 }
967 count++;
968 continue;
969 } else {
970 /* tmp_count == 3 - (we split a lock range in two). */
971 SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
972 SMB_ASSERT(tmp_lock[1].lock_type == UNLOCK_LOCK);
973 SMB_ASSERT(tmp_lock[2].lock_type == locks[i].lock_type);
974
975 memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
976 count++;
977 memcpy(&tp[count], &tmp_lock[2], sizeof(struct lock_struct));
978 count++;
979 overlap_found = True;
980 /* Optimisation... */
981 /* We know we're finished here as we can't overlap any
982 more POSIX locks. Copy the rest of the lock array. */
983 if (i < br_lck->num_locks - 1) {
984 memcpy(&tp[count], &locks[i+1],
985 sizeof(*locks)*((br_lck->num_locks-1) - i));
986 count += ((br_lck->num_locks-1) - i);
987 }
988 break;
989 }
990 }
991
992 if (!overlap_found) {
993 /* Just ignore - no change. */
994 SAFE_FREE(tp);
995 DEBUG(10,("brl_unlock_posix: No overlap - unlocked.\n"));
996 return True;
997 }
998
999 /* Unlock any POSIX regions. */
1000 if(lp_posix_locking(br_lck->fsp->conn->params)) {
1001 release_posix_lock_posix_flavour(br_lck->fsp,
1002 plock->start,
1003 plock->size,
1004 &plock->context,
1005 tp,
1006 count);
1007 }
1008
1009 /* Realloc so we don't leak entries per unlock call. */
1010 if (count) {
1011 tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
1012 if (!tp) {
1013 DEBUG(10,("brl_unlock_posix: realloc fail\n"));
1014 return False;
1015 }
1016 } else {
1017 /* We deleted the last lock. */
1018 SAFE_FREE(tp);
1019 tp = NULL;
1020 }
1021
1022 br_lck->num_locks = count;
1023 SAFE_FREE(br_lck->lock_data);
1024 locks = tp;
1025 br_lck->lock_data = tp;
1026 br_lck->modified = True;
1027
1028 /* Send unlock messages to any pending waiters that overlap. */
1029
1030 for (j=0; j < br_lck->num_locks; j++) {
1031 struct lock_struct *pend_lock = &locks[j];
1032
1033 /* Ignore non-pending locks. */
1034 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
1035 continue;
1036 }
1037
1038 /* We could send specific lock info here... */
1039 if (brl_pending_overlap(plock, pend_lock)) {
1040 DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
1041 procid_str_static(&pend_lock->context.pid )));
1042
1043 messaging_send(msg_ctx, pend_lock->context.pid,
1044 MSG_SMB_UNLOCK, &data_blob_null);
1045 }
1046 }
1047
1048 return True;
1049 }
1050
1051 /****************************************************************************
1052 Unlock a range of bytes.
1053 ****************************************************************************/
1054
1055 bool brl_unlock(struct messaging_context *msg_ctx,
1056 struct byte_range_lock *br_lck,
1057 uint32 smbpid,
1058 struct server_id pid,
1059 br_off start,
1060 br_off size,
1061 enum brl_flavour lock_flav)
1062 {
1063 struct lock_struct lock;
1064
1065 lock.context.smbpid = smbpid;
1066 lock.context.pid = pid;
1067 lock.context.tid = br_lck->fsp->conn->cnum;
1068 lock.start = start;
1069 lock.size = size;
1070 lock.fnum = br_lck->fsp->fnum;
1071 lock.lock_type = UNLOCK_LOCK;
1072 lock.lock_flav = lock_flav;
1073
1074 if (lock_flav == WINDOWS_LOCK) {
1075 return brl_unlock_windows(msg_ctx, br_lck, &lock);
1076 } else {
1077 return brl_unlock_posix(msg_ctx, br_lck, &lock);
1078 }
1079 }
1080
1081 /****************************************************************************
1082 Test if we could add a lock if we wanted to.
1083 Returns True if the region required is currently unlocked, False if locked.
1084 ****************************************************************************/
1085
1086 bool brl_locktest(struct byte_range_lock *br_lck,
1087 uint32 smbpid,
1088 struct server_id pid,
1089 br_off start,
1090 br_off size,
1091 enum brl_type lock_type,
1092 enum brl_flavour lock_flav)
1093 {
1094 bool ret = True;
1095 unsigned int i;
1096 struct lock_struct lock;
1097 const struct lock_struct *locks = br_lck->lock_data;
1098 files_struct *fsp = br_lck->fsp;
1099
1100 lock.context.smbpid = smbpid;
1101 lock.context.pid = pid;
1102 lock.context.tid = br_lck->fsp->conn->cnum;
1103 lock.start = start;
1104 lock.size = size;
1105 lock.fnum = fsp->fnum;
1106 lock.lock_type = lock_type;
1107 lock.lock_flav = lock_flav;
1108
1109 /* Make sure existing locks don't conflict */
1110 for (i=0; i < br_lck->num_locks; i++) {
1111 /*
1112 * Our own locks don't conflict.
1113 */
1114 if (brl_conflict_other(&locks[i], &lock)) {
1115 return False;
1116 }
1117 }
1118
1119 /*
1120 * There is no lock held by an SMB daemon, check to
1121 * see if there is a POSIX lock from a UNIX or NFS process.
1122 * This only conflicts with Windows locks, not POSIX locks.
1123 */
1124
1125 if(lp_posix_locking(fsp->conn->params) && (lock_flav == WINDOWS_LOCK)) {
1126 ret = is_posix_locked(fsp, &start, &size, &lock_type, WINDOWS_LOCK);
1127
1128 DEBUG(10,("brl_locktest: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
1129 (double)start, (double)size, ret ? "locked" : "unlocked",
1130 fsp->fnum, fsp->fsp_name ));
1131
1132 /* We need to return the inverse of is_posix_locked. */
1133 ret = !ret;
1134 }
1135
1136 /* no conflicts - we could have added it */
1137 return ret;
1138 }
1139
1140 /****************************************************************************
1141 Query for existing locks.
1142 ****************************************************************************/
1143
1144 NTSTATUS brl_lockquery(struct byte_range_lock *br_lck,
1145 uint32 *psmbpid,
1146 struct server_id pid,
1147 br_off *pstart,
1148 br_off *psize,
1149 enum brl_type *plock_type,
1150 enum brl_flavour lock_flav)
1151 {
1152 unsigned int i;
1153 struct lock_struct lock;
1154 const struct lock_struct *locks = br_lck->lock_data;
1155 files_struct *fsp = br_lck->fsp;
1156
1157 lock.context.smbpid = *psmbpid;
1158 lock.context.pid = pid;
1159 lock.context.tid = br_lck->fsp->conn->cnum;
1160 lock.start = *pstart;
1161 lock.size = *psize;
1162 lock.fnum = fsp->fnum;
1163 lock.lock_type = *plock_type;
1164 lock.lock_flav = lock_flav;
1165
1166 /* Make sure existing locks don't conflict */
1167 for (i=0; i < br_lck->num_locks; i++) {
1168 const struct lock_struct *exlock = &locks[i];
1169 bool conflict = False;
1170
1171 if (exlock->lock_flav == WINDOWS_LOCK) {
1172 conflict = brl_conflict(exlock, &lock);
1173 } else {
1174 conflict = brl_conflict_posix(exlock, &lock);
1175 }
1176
1177 if (conflict) {
1178 *psmbpid = exlock->context.smbpid;
1179 *pstart = exlock->start;
1180 *psize = exlock->size;
1181 *plock_type = exlock->lock_type;
1182 return NT_STATUS_LOCK_NOT_GRANTED;
1183 }
1184 }
1185
1186 /*
1187 * There is no lock held by an SMB daemon, check to
1188 * see if there is a POSIX lock from a UNIX or NFS process.
1189 */
1190
1191 if(lp_posix_locking(fsp->conn->params)) {
1192 bool ret = is_posix_locked(fsp, pstart, psize, plock_type, POSIX_LOCK);
1193
1194 DEBUG(10,("brl_lockquery: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
1195 (double)*pstart, (double)*psize, ret ? "locked" : "unlocked",
1196 fsp->fnum, fsp->fsp_name ));
1197
1198 if (ret) {
1199 /* Hmmm. No clue what to set smbpid to - use -1. */
1200 *psmbpid = 0xFFFF;
1201 return NT_STATUS_LOCK_NOT_GRANTED;
1202 }
1203 }
1204
1205 return NT_STATUS_OK;
1206 }
1207
1208 /****************************************************************************
1209 Remove a particular pending lock.
1210 ****************************************************************************/
1211
1212 bool brl_lock_cancel(struct byte_range_lock *br_lck,
1213 uint32 smbpid,
1214 struct server_id pid,
1215 br_off start,
1216 br_off size,
1217 enum brl_flavour lock_flav)
1218 {
1219 unsigned int i;
1220 struct lock_struct *locks = br_lck->lock_data;
1221 struct lock_context context;
1222
1223 context.smbpid = smbpid;
1224 context.pid = pid;
1225 context.tid = br_lck->fsp->conn->cnum;
1226
1227 for (i = 0; i < br_lck->num_locks; i++) {
1228 struct lock_struct *lock = &locks[i];
1229
1230 /* For pending locks we *always* care about the fnum. */
1231 if (brl_same_context(&lock->context, &context) &&
1232 lock->fnum == br_lck->fsp->fnum &&
1233 IS_PENDING_LOCK(lock->lock_type) &&
1234 lock->lock_flav == lock_flav &&
1235 lock->start == start &&
1236 lock->size == size) {
1237 break;
1238 }
1239 }
1240
1241 if (i == br_lck->num_locks) {
1242 /* Didn't find it. */
1243 return False;
1244 }
1245
1246 if (i < br_lck->num_locks - 1) {
1247 /* Found this particular pending lock - delete it */
1248 memmove(&locks[i], &locks[i+1],
1249 sizeof(*locks)*((br_lck->num_locks-1) - i));
1250 }
1251
1252 br_lck->num_locks -= 1;
1253 br_lck->modified = True;
1254 return True;
1255 }
1256
1257 /****************************************************************************
1258 Remove any locks associated with a open file.
1259 We return True if this process owns any other Windows locks on this
1260 fd and so we should not immediately close the fd.
1261 ****************************************************************************/
1262
1263 void brl_close_fnum(struct messaging_context *msg_ctx,
1264 struct byte_range_lock *br_lck)
1265 {
1266 files_struct *fsp = br_lck->fsp;
1267 uint16 tid = fsp->conn->cnum;
1268 int fnum = fsp->fnum;
1269 unsigned int i, j, dcount=0;
1270 int num_deleted_windows_locks = 0;
1271 struct lock_struct *locks = br_lck->lock_data;
1272 struct server_id pid = procid_self();
1273 bool unlock_individually = False;
1274
1275 if(lp_posix_locking(fsp->conn->params)) {
1276
1277 /* Check if there are any Windows locks associated with this dev/ino
1278 pair that are not this fnum. If so we need to call unlock on each
1279 one in order to release the system POSIX locks correctly. */
1280
1281 for (i=0; i < br_lck->num_locks; i++) {
1282 struct lock_struct *lock = &locks[i];
1283
1284 if (!procid_equal(&lock->context.pid, &pid)) {
1285 continue;
1286 }
1287
1288 if (lock->lock_type != READ_LOCK && lock->lock_type != WRITE_LOCK) {
1289 continue; /* Ignore pending. */
1290 }
1291
1292 if (lock->context.tid != tid || lock->fnum != fnum) {
1293 unlock_individually = True;
1294 break;
1295 }
1296 }
1297
1298 if (unlock_individually) {
1299 struct lock_struct *locks_copy;
1300 unsigned int num_locks_copy;
1301
1302 /* Copy the current lock array. */
1303 if (br_lck->num_locks) {
1304 locks_copy = (struct lock_struct *)TALLOC_MEMDUP(br_lck, locks, br_lck->num_locks * sizeof(struct lock_struct));
1305 if (!locks_copy) {
1306 smb_panic("brl_close_fnum: talloc failed");
1307 }
1308 } else {
1309 locks_copy = NULL;
1310 }
1311
1312 num_locks_copy = br_lck->num_locks;
1313
1314 for (i=0; i < num_locks_copy; i++) {
1315 struct lock_struct *lock = &locks_copy[i];
1316
1317 if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid) &&
1318 (lock->fnum == fnum)) {
1319 brl_unlock(msg_ctx,
1320 br_lck,
1321 lock->context.smbpid,
1322 pid,
1323 lock->start,
1324 lock->size,
1325 lock->lock_flav);
1326 }
1327 }
1328 return;
1329 }
1330 }
1331
1332 /* We can bulk delete - any POSIX locks will be removed when the fd closes. */
1333
1334 /* Remove any existing locks for this fnum (or any fnum if they're POSIX). */
1335
1336 for (i=0; i < br_lck->num_locks; i++) {
1337 struct lock_struct *lock = &locks[i];
1338 bool del_this_lock = False;
1339
1340 if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid)) {
1341 if ((lock->lock_flav == WINDOWS_LOCK) && (lock->fnum == fnum)) {
1342 del_this_lock = True;
1343 num_deleted_windows_locks++;
1344 } else if (lock->lock_flav == POSIX_LOCK) {
1345 del_this_lock = True;
1346 }
1347 }
1348
1349 if (del_this_lock) {
1350 /* Send unlock messages to any pending waiters that overlap. */
1351 for (j=0; j < br_lck->num_locks; j++) {
1352 struct lock_struct *pend_lock = &locks[j];
1353
1354 /* Ignore our own or non-pending locks. */
1355 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
1356 continue;
1357 }
1358
1359 /* Optimisation - don't send to this fnum as we're
1360 closing it. */
1361 if (pend_lock->context.tid == tid &&
1362 procid_equal(&pend_lock->context.pid, &pid) &&
1363 pend_lock->fnum == fnum) {
1364 continue;
1365 }
1366
1367 /* We could send specific lock info here... */
1368 if (brl_pending_overlap(lock, pend_lock)) {
1369 messaging_send(msg_ctx, pend_lock->context.pid,
1370 MSG_SMB_UNLOCK, &data_blob_null);
1371 }
1372 }
1373
1374 /* found it - delete it */
1375 if (br_lck->num_locks > 1 && i < br_lck->num_locks - 1) {
1376 memmove(&locks[i], &locks[i+1],
1377 sizeof(*locks)*((br_lck->num_locks-1) - i));
1378 }
1379 br_lck->num_locks--;
1380 br_lck->modified = True;
1381 i--;
1382 dcount++;
1383 }
1384 }
1385
1386 if(lp_posix_locking(fsp->conn->params) && num_deleted_windows_locks) {
1387 /* Reduce the Windows lock POSIX reference count on this dev/ino pair. */
1388 reduce_windows_lock_ref_count(fsp, num_deleted_windows_locks);
1389 }
1390 }
1391
1392 /****************************************************************************
1393 Ensure this set of lock entries is valid.
1394 ****************************************************************************/
1395
1396 static bool validate_lock_entries(unsigned int *pnum_entries, struct lock_struct **pplocks)
1397 {
1398 unsigned int i;
1399 unsigned int num_valid_entries = 0;
1400 struct lock_struct *locks = *pplocks;
1401
1402 for (i = 0; i < *pnum_entries; i++) {
1403 struct lock_struct *lock_data = &locks[i];
1404 if (!process_exists(lock_data->context.pid)) {
1405 /* This process no longer exists - mark this
1406 entry as invalid by zeroing it. */
1407 ZERO_STRUCTP(lock_data);
1408 } else {
1409 num_valid_entries++;
1410 }
1411 }
1412
1413 if (num_valid_entries != *pnum_entries) {
1414 struct lock_struct *new_lock_data = NULL;
1415
1416 if (num_valid_entries) {
1417 new_lock_data = SMB_MALLOC_ARRAY(struct lock_struct, num_valid_entries);
1418 if (!new_lock_data) {
1419 DEBUG(3, ("malloc fail\n"));
1420 return False;
1421 }
1422
1423 num_valid_entries = 0;
1424 for (i = 0; i < *pnum_entries; i++) {
1425 struct lock_struct *lock_data = &locks[i];
1426 if (lock_data->context.smbpid &&
1427 lock_data->context.tid) {
1428 /* Valid (nonzero) entry - copy it. */
1429 memcpy(&new_lock_data[num_valid_entries],
1430 lock_data, sizeof(struct lock_struct));
1431 num_valid_entries++;
1432 }
1433 }
1434 }
1435
1436 SAFE_FREE(*pplocks);
1437 *pplocks = new_lock_data;
1438 *pnum_entries = num_valid_entries;
1439 }
1440
1441 return True;
1442 }
1443
1444 struct brl_forall_cb {
1445 void (*fn)(struct file_id id, struct server_id pid,
1446 enum brl_type lock_type,
1447 enum brl_flavour lock_flav,
1448 br_off start, br_off size,
1449 void *private_data);
1450 void *private_data;
1451 };
1452
1453 /****************************************************************************
1454 Traverse the whole database with this function, calling traverse_callback
1455 on each lock.
1456 ****************************************************************************/
1457
1458 static int traverse_fn(struct db_record *rec, void *state)
1459 {
1460 struct brl_forall_cb *cb = (struct brl_forall_cb *)state;
1461 struct lock_struct *locks;
1462 struct file_id *key;
1463 unsigned int i;
1464 unsigned int num_locks = 0;
1465 unsigned int orig_num_locks = 0;
1466
1467 /* In a traverse function we must make a copy of
1468 dbuf before modifying it. */
1469
1470 locks = (struct lock_struct *)memdup(rec->value.dptr,
1471 rec->value.dsize);
1472 if (!locks) {
1473 return -1; /* Terminate traversal. */
1474 }
1475
1476 key = (struct file_id *)rec->key.dptr;
1477 orig_num_locks = num_locks = rec->value.dsize/sizeof(*locks);
1478
1479 /* Ensure the lock db is clean of entries from invalid processes. */
1480
1481 if (!validate_lock_entries(&num_locks, &locks)) {
1482 SAFE_FREE(locks);
1483 return -1; /* Terminate traversal */
1484 }
1485
1486 if (orig_num_locks != num_locks) {
1487 if (num_locks) {
1488 TDB_DATA data;
1489 data.dptr = (uint8_t *)locks;
1490 data.dsize = num_locks*sizeof(struct lock_struct);
1491 rec->store(rec, data, TDB_REPLACE);
1492 } else {
1493 rec->delete_rec(rec);
1494 }
1495 }
1496
1497 if (cb->fn) {
1498 for ( i=0; i<num_locks; i++) {
1499 cb->fn(*key,
1500 locks[i].context.pid,
1501 locks[i].lock_type,
1502 locks[i].lock_flav,
1503 locks[i].start,
1504 locks[i].size,
1505 cb->private_data);
1506 }
1507 }
1508
1509 SAFE_FREE(locks);
1510 return 0;
1511 }
1512
1513 /*******************************************************************
1514 Call the specified function on each lock in the database.
1515 ********************************************************************/
1516
1517 int brl_forall(void (*fn)(struct file_id id, struct server_id pid,
1518 enum brl_type lock_type,
1519 enum brl_flavour lock_flav,
1520 br_off start, br_off size,
1521 void *private_data),
1522 void *private_data)
1523 {
1524 struct brl_forall_cb cb;
1525
1526 if (!brlock_db) {
1527 return 0;
1528 }
1529 cb.fn = fn;
1530 cb.private_data = private_data;
1531 return brlock_db->traverse(brlock_db, traverse_fn, &cb);
1532 }
1533
1534 /*******************************************************************
1535 Store a potentially modified set of byte range lock data back into
1536 the database.
1537 Unlock the record.
1538 ********************************************************************/
1539
1540 static int byte_range_lock_destructor(struct byte_range_lock *br_lck)
1541 {
1542 TDB_DATA key;
1543
1544 key.dptr = (uint8 *)&br_lck->key;
1545 key.dsize = sizeof(struct file_id);
1546
1547 if (br_lck->read_only) {
1548 SMB_ASSERT(!br_lck->modified);
1549 }
1550
1551 if (!br_lck->modified) {
1552 goto done;
1553 }
1554
1555 if (br_lck->num_locks == 0) {
1556 /* No locks - delete this entry. */
1557 NTSTATUS status = br_lck->record->delete_rec(br_lck->record);
1558 if (!NT_STATUS_IS_OK(status)) {
1559 DEBUG(0, ("delete_rec returned %s\n",
1560 nt_errstr(status)));
1561 smb_panic("Could not delete byte range lock entry");
1562 }
1563 } else {
1564 TDB_DATA data;
1565 NTSTATUS status;
1566
1567 data.dptr = (uint8 *)br_lck->lock_data;
1568 data.dsize = br_lck->num_locks * sizeof(struct lock_struct);
1569
1570 status = br_lck->record->store(br_lck->record, data,
1571 TDB_REPLACE);
1572 if (!NT_STATUS_IS_OK(status)) {
1573 DEBUG(0, ("store returned %s\n", nt_errstr(status)));
1574 smb_panic("Could not store byte range mode entry");
1575 }
1576 }
1577
1578 done:
1579
1580 SAFE_FREE(br_lck->lock_data);
1581 TALLOC_FREE(br_lck->record);
1582 return 0;
1583 }
1584
1585 /*******************************************************************
1586 Fetch a set of byte range lock data from the database.
1587 Leave the record locked.
1588 TALLOC_FREE(brl) will release the lock in the destructor.
1589 ********************************************************************/
1590
1591 static struct byte_range_lock *brl_get_locks_internal(TALLOC_CTX *mem_ctx,
1592 files_struct *fsp, bool read_only)
1593 {
1594 TDB_DATA key, data;
1595 struct byte_range_lock *br_lck = TALLOC_P(mem_ctx, struct byte_range_lock);
1596
1597 if (br_lck == NULL) {
1598 return NULL;
1599 }
1600
1601 br_lck->fsp = fsp;
1602 br_lck->num_locks = 0;
1603 br_lck->modified = False;
1604 memset(&br_lck->key, '\0', sizeof(struct file_id));
1605 br_lck->key = fsp->file_id;
1606
1607 key.dptr = (uint8 *)&br_lck->key;
1608 key.dsize = sizeof(struct file_id);
1609
1610 if (!fsp->lockdb_clean) {
1611 /* We must be read/write to clean
1612 the dead entries. */
1613 read_only = False;
1614 }
1615
1616 if (read_only) {
1617 if (brlock_db->fetch(brlock_db, br_lck, key, &data) == -1) {
1618 DEBUG(3, ("Could not fetch byte range lock record\n"));
1619 TALLOC_FREE(br_lck);
1620 return NULL;
1621 }
1622 br_lck->record = NULL;
1623 }
1624 else {
1625 br_lck->record = brlock_db->fetch_locked(brlock_db, br_lck, key);
1626
1627 if (br_lck->record == NULL) {
1628 DEBUG(3, ("Could not lock byte range lock entry\n"));
1629 TALLOC_FREE(br_lck);
1630 return NULL;
1631 }
1632
1633 data = br_lck->record->value;
1634 }
1635
1636 br_lck->read_only = read_only;
1637 br_lck->lock_data = NULL;
1638
1639 talloc_set_destructor(br_lck, byte_range_lock_destructor);
1640
1641 br_lck->num_locks = data.dsize / sizeof(struct lock_struct);
1642
1643 if (br_lck->num_locks != 0) {
1644 br_lck->lock_data = SMB_MALLOC_ARRAY(struct lock_struct,
1645 br_lck->num_locks);
1646 if (br_lck->lock_data == NULL) {
1647 DEBUG(0, ("malloc failed\n"));
1648 TALLOC_FREE(br_lck);
1649 return NULL;
1650 }
1651
1652 memcpy(br_lck->lock_data, data.dptr, data.dsize);
1653 }
1654
1655 if (!fsp->lockdb_clean) {
1656 int orig_num_locks = br_lck->num_locks;
1657
1658 /* This is the first time we've accessed this. */
1659 /* Go through and ensure all entries exist - remove any that don't. */
1660 /* Makes the lockdb self cleaning at low cost. */
1661
1662 if (!validate_lock_entries(&br_lck->num_locks,
1663 &br_lck->lock_data)) {
1664 SAFE_FREE(br_lck->lock_data);
1665 TALLOC_FREE(br_lck);
1666 return NULL;
1667 }
1668
1669 /* Ensure invalid locks are cleaned up in the destructor. */
1670 if (orig_num_locks != br_lck->num_locks) {
1671 br_lck->modified = True;
1672 }
1673
1674 /* Mark the lockdb as "clean" as seen from this open file. */
1675 fsp->lockdb_clean = True;
1676 }
1677
1678 if (DEBUGLEVEL >= 10) {
1679 unsigned int i;
1680 struct lock_struct *locks = br_lck->lock_data;
1681 DEBUG(10,("brl_get_locks_internal: %u current locks on file_id %s\n",
1682 br_lck->num_locks,
1683 file_id_string_tos(&fsp->file_id)));
1684 for( i = 0; i < br_lck->num_locks; i++) {
1685 print_lock_struct(i, &locks[i]);
1686 }
1687 }
1688 return br_lck;
1689 }
1690
1691 struct byte_range_lock *brl_get_locks(TALLOC_CTX *mem_ctx,
1692 files_struct *fsp)
1693 {
1694 return brl_get_locks_internal(mem_ctx, fsp, False);
1695 }
1696
1697 struct byte_range_lock *brl_get_locks_readonly(TALLOC_CTX *mem_ctx,
1698 files_struct *fsp)
1699 {
1700 return brl_get_locks_internal(mem_ctx, fsp, True);
1701 }
1702
1703 struct brl_revalidate_state {
1704 ssize_t array_size;
1705 uint32 num_pids;
1706 struct server_id *pids;
1707 };
1708
1709 /*
1710 * Collect PIDs of all processes with pending entries
1711 */
1712
1713 static void brl_revalidate_collect(struct file_id id, struct server_id pid,
1714 enum brl_type lock_type,
1715 enum brl_flavour lock_flav,
1716 br_off start, br_off size,
1717 void *private_data)
1718 {
1719 struct brl_revalidate_state *state =
1720 (struct brl_revalidate_state *)private_data;
1721
1722 if (!IS_PENDING_LOCK(lock_type)) {
1723 return;
1724 }
1725
1726 add_to_large_array(state, sizeof(pid), (void *)&pid,
1727 &state->pids, &state->num_pids,
1728 &state->array_size);
1729 }
1730
1731 /*
1732 * qsort callback to sort the processes
1733 */
1734
1735 static int compare_procids(const void *p1, const void *p2)
1736 {
1737 const struct server_id *i1 = (struct server_id *)p1;
1738 const struct server_id *i2 = (struct server_id *)p2;
1739
1740 if (i1->pid < i2->pid) return -1;
1741 if (i2->pid > i2->pid) return 1;
1742 return 0;
1743 }
1744
1745 /*
1746 * Send a MSG_SMB_UNLOCK message to all processes with pending byte range
1747 * locks so that they retry. Mainly used in the cluster code after a node has
1748 * died.
1749 *
1750 * Done in two steps to avoid double-sends: First we collect all entries in an
1751 * array, then qsort that array and only send to non-dupes.
1752 */
1753
1754 static void brl_revalidate(struct messaging_context *msg_ctx,
1755 void *private_data,
1756 uint32_t msg_type,
1757 struct server_id server_id,
1758 DATA_BLOB *data)
1759 {
1760 struct brl_revalidate_state *state;
1761 uint32 i;
1762 struct server_id last_pid;
1763
1764 if (!(state = TALLOC_ZERO_P(NULL, struct brl_revalidate_state))) {
1765 DEBUG(0, ("talloc failed\n"));
1766 return;
1767 }
1768
1769 brl_forall(brl_revalidate_collect, state);
1770
1771 if (state->array_size == -1) {
1772 DEBUG(0, ("talloc failed\n"));
1773 goto done;
1774 }
1775
1776 if (state->num_pids == 0) {
1777 goto done;
1778 }
1779
1780 qsort(state->pids, state->num_pids, sizeof(state->pids[0]),
1781 compare_procids);
1782
1783 ZERO_STRUCT(last_pid);
1784
1785 for (i=0; i<state->num_pids; i++) {
1786 if (procid_equal(&last_pid, &state->pids[i])) {
1787 /*
1788 * We've seen that one already
1789 */
1790 continue;
1791 }
1792
1793 messaging_send(msg_ctx, state->pids[i], MSG_SMB_UNLOCK,
1794 &data_blob_null);
1795 last_pid = state->pids[i];
1796 }
1797
1798 done:
1799 TALLOC_FREE(state);
1800 return;
1801 }
1802
1803 void brl_register_msgs(struct messaging_context *msg_ctx)
1804 {
1805 messaging_register(msg_ctx, NULL, MSG_SMB_BRL_VALIDATE,
1806 brl_revalidate);
1807 }
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