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s3: Remove a pointless memset
[Samba/fernandojvsilva.git] / source3 / locking / brlock.c
blobb021293c7b8c64f3f1260dab7e28ee2cf6f57b72
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 = %s, ",
45 i,
46 (unsigned int)pls->context.smbpid,
47 (unsigned int)pls->context.tid,
48 procid_str(talloc_tos(), &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 /* XXX Remove for Win7 compatibility. */
78 /* this extra check is not redundent - it copes with locks
79 that go beyond the end of 64 bit file space */
80 if (lck1->size != 0 &&
81 lck1->start == lck2->start &&
82 lck1->size == lck2->size) {
83 return True;
84 }
85
86 if (lck1->start >= (lck2->start+lck2->size) ||
87 lck2->start >= (lck1->start+lck1->size)) {
88 return False;
89 }
90 return True;
91 }
92
93 /****************************************************************************
94 See if lock2 can be added when lock1 is in place.
95 ****************************************************************************/
96
97 static bool brl_conflict(const struct lock_struct *lck1,
98 const struct lock_struct *lck2)
99 {
100 /* Ignore PENDING locks. */
101 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
102 return False;
103
104 /* Read locks never conflict. */
105 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
106 return False;
107 }
108
109 /* A READ lock can stack on top of a WRITE lock if they have the same
110 * context & fnum. */
111 if (lck1->lock_type == WRITE_LOCK && lck2->lock_type == READ_LOCK &&
112 brl_same_context(&lck1->context, &lck2->context) &&
113 lck1->fnum == lck2->fnum) {
114 return False;
115 }
116
117 return brl_overlap(lck1, lck2);
118 }
119
120 /****************************************************************************
121 See if lock2 can be added when lock1 is in place - when both locks are POSIX
122 flavour. POSIX locks ignore fnum - they only care about dev/ino which we
123 know already match.
124 ****************************************************************************/
125
126 static bool brl_conflict_posix(const struct lock_struct *lck1,
127 const struct lock_struct *lck2)
128 {
129 #if defined(DEVELOPER)
130 SMB_ASSERT(lck1->lock_flav == POSIX_LOCK);
131 SMB_ASSERT(lck2->lock_flav == POSIX_LOCK);
132 #endif
133
134 /* Ignore PENDING locks. */
135 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
136 return False;
137
138 /* Read locks never conflict. */
139 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
140 return False;
141 }
142
143 /* Locks on the same context con't conflict. Ignore fnum. */
144 if (brl_same_context(&lck1->context, &lck2->context)) {
145 return False;
146 }
147
148 /* One is read, the other write, or the context is different,
149 do they overlap ? */
150 return brl_overlap(lck1, lck2);
151 }
152
153 #if ZERO_ZERO
154 static bool brl_conflict1(const struct lock_struct *lck1,
155 const struct lock_struct *lck2)
156 {
157 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
158 return False;
159
160 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
161 return False;
162 }
163
164 if (brl_same_context(&lck1->context, &lck2->context) &&
165 lck2->lock_type == READ_LOCK && lck1->fnum == lck2->fnum) {
166 return False;
167 }
168
169 if (lck2->start == 0 && lck2->size == 0 && lck1->size != 0) {
170 return True;
171 }
172
173 if (lck1->start >= (lck2->start + lck2->size) ||
174 lck2->start >= (lck1->start + lck1->size)) {
175 return False;
176 }
177
178 return True;
179 }
180 #endif
181
182 /****************************************************************************
183 Check to see if this lock conflicts, but ignore our own locks on the
184 same fnum only. This is the read/write lock check code path.
185 This is never used in the POSIX lock case.
186 ****************************************************************************/
187
188 static bool brl_conflict_other(const struct lock_struct *lck1, const struct lock_struct *lck2)
189 {
190 if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
191 return False;
192
193 if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK)
194 return False;
195
196 /* POSIX flavour locks never conflict here - this is only called
197 in the read/write path. */
198
199 if (lck1->lock_flav == POSIX_LOCK && lck2->lock_flav == POSIX_LOCK)
200 return False;
201
202 /*
203 * Incoming WRITE locks conflict with existing READ locks even
204 * if the context is the same. JRA. See LOCKTEST7 in smbtorture.
205 */
206
207 if (!(lck2->lock_type == WRITE_LOCK && lck1->lock_type == READ_LOCK)) {
208 if (brl_same_context(&lck1->context, &lck2->context) &&
209 lck1->fnum == lck2->fnum)
210 return False;
211 }
212
213 return brl_overlap(lck1, lck2);
214 }
215
216 /****************************************************************************
217 Check if an unlock overlaps a pending lock.
218 ****************************************************************************/
219
220 static bool brl_pending_overlap(const struct lock_struct *lock, const struct lock_struct *pend_lock)
221 {
222 if ((lock->start <= pend_lock->start) && (lock->start + lock->size > pend_lock->start))
223 return True;
224 if ((lock->start >= pend_lock->start) && (lock->start <= pend_lock->start + pend_lock->size))
225 return True;
226 return False;
227 }
228
229 /****************************************************************************
230 Amazingly enough, w2k3 "remembers" whether the last lock failure on a fnum
231 is the same as this one and changes its error code. I wonder if any
232 app depends on this ?
233 ****************************************************************************/
234
235 NTSTATUS brl_lock_failed(files_struct *fsp, const struct lock_struct *lock, bool blocking_lock)
236 {
237 if (lock->start >= 0xEF000000 && (lock->start >> 63) == 0) {
238 /* amazing the little things you learn with a test
239 suite. Locks beyond this offset (as a 64 bit
240 number!) always generate the conflict error code,
241 unless the top bit is set */
242 if (!blocking_lock) {
243 fsp->last_lock_failure = *lock;
244 }
245 return NT_STATUS_FILE_LOCK_CONFLICT;
246 }
247
248 if (procid_equal(&lock->context.pid, &fsp->last_lock_failure.context.pid) &&
249 lock->context.tid == fsp->last_lock_failure.context.tid &&
250 lock->fnum == fsp->last_lock_failure.fnum &&
251 lock->start == fsp->last_lock_failure.start) {
252 return NT_STATUS_FILE_LOCK_CONFLICT;
253 }
254
255 if (!blocking_lock) {
256 fsp->last_lock_failure = *lock;
257 }
258 return NT_STATUS_LOCK_NOT_GRANTED;
259 }
260
261 /****************************************************************************
262 Open up the brlock.tdb database.
263 ****************************************************************************/
264
265 void brl_init(bool read_only)
266 {
267 int tdb_flags;
268
269 if (brlock_db) {
270 return;
271 }
272
273 tdb_flags = TDB_DEFAULT|TDB_VOLATILE|TDB_CLEAR_IF_FIRST;
274
275 if (!lp_clustering()) {
276 /*
277 * We can't use the SEQNUM trick to cache brlock
278 * entries in the clustering case because ctdb seqnum
279 * propagation has a delay.
280 */
281 tdb_flags |= TDB_SEQNUM;
282 }
283
284 brlock_db = db_open(NULL, lock_path("brlock.tdb"),
285 lp_open_files_db_hash_size(), tdb_flags,
286 read_only?O_RDONLY:(O_RDWR|O_CREAT), 0644 );
287 if (!brlock_db) {
288 DEBUG(0,("Failed to open byte range locking database %s\n",
289 lock_path("brlock.tdb")));
290 return;
291 }
292 }
293
294 /****************************************************************************
295 Close down the brlock.tdb database.
296 ****************************************************************************/
297
298 void brl_shutdown(void)
299 {
300 TALLOC_FREE(brlock_db);
301 }
302
303 #if ZERO_ZERO
304 /****************************************************************************
305 Compare two locks for sorting.
306 ****************************************************************************/
307
308 static int lock_compare(const struct lock_struct *lck1,
309 const struct lock_struct *lck2)
310 {
311 if (lck1->start != lck2->start) {
312 return (lck1->start - lck2->start);
313 }
314 if (lck2->size != lck1->size) {
315 return ((int)lck1->size - (int)lck2->size);
316 }
317 return 0;
318 }
319 #endif
320
321 /****************************************************************************
322 Lock a range of bytes - Windows lock semantics.
323 ****************************************************************************/
324
325 NTSTATUS brl_lock_windows_default(struct byte_range_lock *br_lck,
326 struct lock_struct *plock, bool blocking_lock)
327 {
328 unsigned int i;
329 files_struct *fsp = br_lck->fsp;
330 struct lock_struct *locks = br_lck->lock_data;
331 NTSTATUS status;
332
333 SMB_ASSERT(plock->lock_type != UNLOCK_LOCK);
334
335 for (i=0; i < br_lck->num_locks; i++) {
336 /* Do any Windows or POSIX locks conflict ? */
337 if (brl_conflict(&locks[i], plock)) {
338 /* Remember who blocked us. */
339 plock->context.smbpid = locks[i].context.smbpid;
340 return brl_lock_failed(fsp,plock,blocking_lock);
341 }
342 #if ZERO_ZERO
343 if (plock->start == 0 && plock->size == 0 &&
344 locks[i].size == 0) {
345 break;
346 }
347 #endif
348 }
349
350 if (!IS_PENDING_LOCK(plock->lock_type)) {
351 contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_WINDOWS_BRL);
352 }
353
354 /* We can get the Windows lock, now see if it needs to
355 be mapped into a lower level POSIX one, and if so can
356 we get it ? */
357
358 if (!IS_PENDING_LOCK(plock->lock_type) && lp_posix_locking(fsp->conn->params)) {
359 int errno_ret;
360 if (!set_posix_lock_windows_flavour(fsp,
361 plock->start,
362 plock->size,
363 plock->lock_type,
364 &plock->context,
365 locks,
366 br_lck->num_locks,
367 &errno_ret)) {
368
369 /* We don't know who blocked us. */
370 plock->context.smbpid = 0xFFFFFFFF;
371
372 if (errno_ret == EACCES || errno_ret == EAGAIN) {
373 status = NT_STATUS_FILE_LOCK_CONFLICT;
374 goto fail;
375 } else {
376 status = map_nt_error_from_unix(errno);
377 goto fail;
378 }
379 }
380 }
381
382 /* no conflicts - add it to the list of locks */
383 locks = (struct lock_struct *)SMB_REALLOC(locks, (br_lck->num_locks + 1) * sizeof(*locks));
384 if (!locks) {
385 status = NT_STATUS_NO_MEMORY;
386 goto fail;
387 }
388
389 memcpy(&locks[br_lck->num_locks], plock, sizeof(struct lock_struct));
390 br_lck->num_locks += 1;
391 br_lck->lock_data = locks;
392 br_lck->modified = True;
393
394 return NT_STATUS_OK;
395 fail:
396 if (!IS_PENDING_LOCK(plock->lock_type)) {
397 contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_WINDOWS_BRL);
398 }
399 return status;
400 }
401
402 /****************************************************************************
403 Cope with POSIX range splits and merges.
404 ****************************************************************************/
405
406 static unsigned int brlock_posix_split_merge(struct lock_struct *lck_arr, /* Output array. */
407 struct lock_struct *ex, /* existing lock. */
408 struct lock_struct *plock) /* proposed lock. */
409 {
410 bool lock_types_differ = (ex->lock_type != plock->lock_type);
411
412 /* We can't merge non-conflicting locks on different context - ignore fnum. */
413
414 if (!brl_same_context(&ex->context, &plock->context)) {
415 /* Just copy. */
416 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
417 return 1;
418 }
419
420 /* We now know we have the same context. */
421
422 /* Did we overlap ? */
423
424 /*********************************************
425 +---------+
426 | ex |
427 +---------+
428 +-------+
429 | plock |
430 +-------+
431 OR....
432 +---------+
433 | ex |
434 +---------+
435 **********************************************/
436
437 if ( (ex->start > (plock->start + plock->size)) ||
438 (plock->start > (ex->start + ex->size))) {
439
440 /* No overlap with this lock - copy existing. */
441
442 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
443 return 1;
444 }
445
446 /*********************************************
447 +---------------------------+
448 | ex |
449 +---------------------------+
450 +---------------------------+
451 | plock | -> replace with plock.
452 +---------------------------+
453 OR
454 +---------------+
455 | ex |
456 +---------------+
457 +---------------------------+
458 | plock | -> replace with plock.
459 +---------------------------+
460
461 **********************************************/
462
463 if ( (ex->start >= plock->start) &&
464 (ex->start + ex->size <= plock->start + plock->size) ) {
465
466 /* Replace - discard existing lock. */
467
468 return 0;
469 }
470
471 /*********************************************
472 Adjacent after.
473 +-------+
474 | ex |
475 +-------+
476 +---------------+
477 | plock |
478 +---------------+
479
480 BECOMES....
481 +---------------+-------+
482 | plock | ex | - different lock types.
483 +---------------+-------+
484 OR.... (merge)
485 +-----------------------+
486 | plock | - same lock type.
487 +-----------------------+
488 **********************************************/
489
490 if (plock->start + plock->size == ex->start) {
491
492 /* If the lock types are the same, we merge, if different, we
493 add the remainder of the old lock. */
494
495 if (lock_types_differ) {
496 /* Add existing. */
497 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
498 return 1;
499 } else {
500 /* Merge - adjust incoming lock as we may have more
501 * merging to come. */
502 plock->size += ex->size;
503 return 0;
504 }
505 }
506
507 /*********************************************
508 Adjacent before.
509 +-------+
510 | ex |
511 +-------+
512 +---------------+
513 | plock |
514 +---------------+
515 BECOMES....
516 +-------+---------------+
517 | ex | plock | - different lock types
518 +-------+---------------+
519
520 OR.... (merge)
521 +-----------------------+
522 | plock | - same lock type.
523 +-----------------------+
524
525 **********************************************/
526
527 if (ex->start + ex->size == plock->start) {
528
529 /* If the lock types are the same, we merge, if different, we
530 add the existing lock. */
531
532 if (lock_types_differ) {
533 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
534 return 1;
535 } else {
536 /* Merge - adjust incoming lock as we may have more
537 * merging to come. */
538 plock->start = ex->start;
539 plock->size += ex->size;
540 return 0;
541 }
542 }
543
544 /*********************************************
545 Overlap after.
546 +-----------------------+
547 | ex |
548 +-----------------------+
549 +---------------+
550 | plock |
551 +---------------+
552 OR
553 +----------------+
554 | ex |
555 +----------------+
556 +---------------+
557 | plock |
558 +---------------+
559
560 BECOMES....
561 +---------------+-------+
562 | plock | ex | - different lock types.
563 +---------------+-------+
564 OR.... (merge)
565 +-----------------------+
566 | plock | - same lock type.
567 +-----------------------+
568 **********************************************/
569
570 if ( (ex->start >= plock->start) &&
571 (ex->start <= plock->start + plock->size) &&
572 (ex->start + ex->size > plock->start + plock->size) ) {
573
574 /* If the lock types are the same, we merge, if different, we
575 add the remainder of the old lock. */
576
577 if (lock_types_differ) {
578 /* Add remaining existing. */
579 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
580 /* Adjust existing start and size. */
581 lck_arr[0].start = plock->start + plock->size;
582 lck_arr[0].size = (ex->start + ex->size) - (plock->start + plock->size);
583 return 1;
584 } else {
585 /* Merge - adjust incoming lock as we may have more
586 * merging to come. */
587 plock->size += (ex->start + ex->size) - (plock->start + plock->size);
588 return 0;
589 }
590 }
591
592 /*********************************************
593 Overlap before.
594 +-----------------------+
595 | ex |
596 +-----------------------+
597 +---------------+
598 | plock |
599 +---------------+
600 OR
601 +-------------+
602 | ex |
603 +-------------+
604 +---------------+
605 | plock |
606 +---------------+
607
608 BECOMES....
609 +-------+---------------+
610 | ex | plock | - different lock types
611 +-------+---------------+
612
613 OR.... (merge)
614 +-----------------------+
615 | plock | - same lock type.
616 +-----------------------+
617
618 **********************************************/
619
620 if ( (ex->start < plock->start) &&
621 (ex->start + ex->size >= plock->start) &&
622 (ex->start + ex->size <= plock->start + plock->size) ) {
623
624 /* If the lock types are the same, we merge, if different, we
625 add the truncated old lock. */
626
627 if (lock_types_differ) {
628 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
629 /* Adjust existing size. */
630 lck_arr[0].size = plock->start - ex->start;
631 return 1;
632 } else {
633 /* Merge - adjust incoming lock as we may have more
634 * merging to come. MUST ADJUST plock SIZE FIRST ! */
635 plock->size += (plock->start - ex->start);
636 plock->start = ex->start;
637 return 0;
638 }
639 }
640
641 /*********************************************
642 Complete overlap.
643 +---------------------------+
644 | ex |
645 +---------------------------+
646 +---------+
647 | plock |
648 +---------+
649 BECOMES.....
650 +-------+---------+---------+
651 | ex | plock | ex | - different lock types.
652 +-------+---------+---------+
653 OR
654 +---------------------------+
655 | plock | - same lock type.
656 +---------------------------+
657 **********************************************/
658
659 if ( (ex->start < plock->start) && (ex->start + ex->size > plock->start + plock->size) ) {
660
661 if (lock_types_differ) {
662
663 /* We have to split ex into two locks here. */
664
665 memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
666 memcpy(&lck_arr[1], ex, sizeof(struct lock_struct));
667
668 /* Adjust first existing size. */
669 lck_arr[0].size = plock->start - ex->start;
670
671 /* Adjust second existing start and size. */
672 lck_arr[1].start = plock->start + plock->size;
673 lck_arr[1].size = (ex->start + ex->size) - (plock->start + plock->size);
674 return 2;
675 } else {
676 /* Just eat the existing locks, merge them into plock. */
677 plock->start = ex->start;
678 plock->size = ex->size;
679 return 0;
680 }
681 }
682
683 /* Never get here. */
684 smb_panic("brlock_posix_split_merge");
685 /* Notreached. */
686
687 /* Keep some compilers happy. */
688 return 0;
689 }
690
691 /****************************************************************************
692 Lock a range of bytes - POSIX lock semantics.
693 We must cope with range splits and merges.
694 ****************************************************************************/
695
696 static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
697 struct byte_range_lock *br_lck,
698 struct lock_struct *plock)
699 {
700 unsigned int i, count, posix_count;
701 struct lock_struct *locks = br_lck->lock_data;
702 struct lock_struct *tp;
703 bool signal_pending_read = False;
704 bool break_oplocks = false;
705 NTSTATUS status;
706
707 /* No zero-zero locks for POSIX. */
708 if (plock->start == 0 && plock->size == 0) {
709 return NT_STATUS_INVALID_PARAMETER;
710 }
711
712 /* Don't allow 64-bit lock wrap. */
713 if (plock->start + plock->size < plock->start ||
714 plock->start + plock->size < plock->size) {
715 return NT_STATUS_INVALID_PARAMETER;
716 }
717
718 /* The worst case scenario here is we have to split an
719 existing POSIX lock range into two, and add our lock,
720 so we need at most 2 more entries. */
721
722 tp = SMB_MALLOC_ARRAY(struct lock_struct, (br_lck->num_locks + 2));
723 if (!tp) {
724 return NT_STATUS_NO_MEMORY;
725 }
726
727 count = posix_count = 0;
728
729 for (i=0; i < br_lck->num_locks; i++) {
730 struct lock_struct *curr_lock = &locks[i];
731
732 /* If we have a pending read lock, a lock downgrade should
733 trigger a lock re-evaluation. */
734 if (curr_lock->lock_type == PENDING_READ_LOCK &&
735 brl_pending_overlap(plock, curr_lock)) {
736 signal_pending_read = True;
737 }
738
739 if (curr_lock->lock_flav == WINDOWS_LOCK) {
740 /* Do any Windows flavour locks conflict ? */
741 if (brl_conflict(curr_lock, plock)) {
742 /* No games with error messages. */
743 SAFE_FREE(tp);
744 /* Remember who blocked us. */
745 plock->context.smbpid = curr_lock->context.smbpid;
746 return NT_STATUS_FILE_LOCK_CONFLICT;
747 }
748 /* Just copy the Windows lock into the new array. */
749 memcpy(&tp[count], curr_lock, sizeof(struct lock_struct));
750 count++;
751 } else {
752 unsigned int tmp_count = 0;
753
754 /* POSIX conflict semantics are different. */
755 if (brl_conflict_posix(curr_lock, plock)) {
756 /* Can't block ourselves with POSIX locks. */
757 /* No games with error messages. */
758 SAFE_FREE(tp);
759 /* Remember who blocked us. */
760 plock->context.smbpid = curr_lock->context.smbpid;
761 return NT_STATUS_FILE_LOCK_CONFLICT;
762 }
763
764 /* Work out overlaps. */
765 tmp_count += brlock_posix_split_merge(&tp[count], curr_lock, plock);
766 posix_count += tmp_count;
767 count += tmp_count;
768 }
769 }
770
771 /*
772 * Break oplocks while we hold a brl. Since lock() and unlock() calls
773 * are not symetric with POSIX semantics, we cannot guarantee our
774 * contend_level2_oplocks_begin/end calls will be acquired and
775 * released one-for-one as with Windows semantics. Therefore we only
776 * call contend_level2_oplocks_begin if this is the first POSIX brl on
777 * the file.
778 */
779 break_oplocks = (!IS_PENDING_LOCK(plock->lock_type) &&
780 posix_count == 0);
781 if (break_oplocks) {
782 contend_level2_oplocks_begin(br_lck->fsp,
783 LEVEL2_CONTEND_POSIX_BRL);
784 }
785
786 /* Try and add the lock in order, sorted by lock start. */
787 for (i=0; i < count; i++) {
788 struct lock_struct *curr_lock = &tp[i];
789
790 if (curr_lock->start <= plock->start) {
791 continue;
792 }
793 }
794
795 if (i < count) {
796 memmove(&tp[i+1], &tp[i],
797 (count - i)*sizeof(struct lock_struct));
798 }
799 memcpy(&tp[i], plock, sizeof(struct lock_struct));
800 count++;
801
802 /* We can get the POSIX lock, now see if it needs to
803 be mapped into a lower level POSIX one, and if so can
804 we get it ? */
805
806 if (!IS_PENDING_LOCK(plock->lock_type) && lp_posix_locking(br_lck->fsp->conn->params)) {
807 int errno_ret;
808
809 /* The lower layer just needs to attempt to
810 get the system POSIX lock. We've weeded out
811 any conflicts above. */
812
813 if (!set_posix_lock_posix_flavour(br_lck->fsp,
814 plock->start,
815 plock->size,
816 plock->lock_type,
817 &errno_ret)) {
818
819 /* We don't know who blocked us. */
820 plock->context.smbpid = 0xFFFFFFFF;
821
822 if (errno_ret == EACCES || errno_ret == EAGAIN) {
823 SAFE_FREE(tp);
824 status = NT_STATUS_FILE_LOCK_CONFLICT;
825 goto fail;
826 } else {
827 SAFE_FREE(tp);
828 status = map_nt_error_from_unix(errno);
829 goto fail;
830 }
831 }
832 }
833
834 /* If we didn't use all the allocated size,
835 * Realloc so we don't leak entries per lock call. */
836 if (count < br_lck->num_locks + 2) {
837 tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
838 if (!tp) {
839 status = NT_STATUS_NO_MEMORY;
840 goto fail;
841 }
842 }
843
844 br_lck->num_locks = count;
845 SAFE_FREE(br_lck->lock_data);
846 br_lck->lock_data = tp;
847 locks = tp;
848 br_lck->modified = True;
849
850 /* A successful downgrade from write to read lock can trigger a lock
851 re-evalutation where waiting readers can now proceed. */
852
853 if (signal_pending_read) {
854 /* Send unlock messages to any pending read waiters that overlap. */
855 for (i=0; i < br_lck->num_locks; i++) {
856 struct lock_struct *pend_lock = &locks[i];
857
858 /* Ignore non-pending locks. */
859 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
860 continue;
861 }
862
863 if (pend_lock->lock_type == PENDING_READ_LOCK &&
864 brl_pending_overlap(plock, pend_lock)) {
865 DEBUG(10,("brl_lock_posix: sending unlock message to pid %s\n",
866 procid_str_static(&pend_lock->context.pid )));
867
868 messaging_send(msg_ctx, pend_lock->context.pid,
869 MSG_SMB_UNLOCK, &data_blob_null);
870 }
871 }
872 }
873
874 return NT_STATUS_OK;
875 fail:
876 if (break_oplocks) {
877 contend_level2_oplocks_end(br_lck->fsp,
878 LEVEL2_CONTEND_POSIX_BRL);
879 }
880 return status;
881 }
882
883 NTSTATUS smb_vfs_call_brl_lock_windows(struct vfs_handle_struct *handle,
884 struct byte_range_lock *br_lck,
885 struct lock_struct *plock,
886 bool blocking_lock,
887 struct blocking_lock_record *blr)
888 {
889 VFS_FIND(brl_lock_windows);
890 return handle->fns->brl_lock_windows(handle, br_lck, plock,
891 blocking_lock, blr);
892 }
893
894 /****************************************************************************
895 Lock a range of bytes.
896 ****************************************************************************/
897
898 NTSTATUS brl_lock(struct messaging_context *msg_ctx,
899 struct byte_range_lock *br_lck,
900 uint32 smbpid,
901 struct server_id pid,
902 br_off start,
903 br_off size,
904 enum brl_type lock_type,
905 enum brl_flavour lock_flav,
906 bool blocking_lock,
907 uint32 *psmbpid,
908 struct blocking_lock_record *blr)
909 {
910 NTSTATUS ret;
911 struct lock_struct lock;
912
913 #if !ZERO_ZERO
914 if (start == 0 && size == 0) {
915 DEBUG(0,("client sent 0/0 lock - please report this\n"));
916 }
917 #endif
918
919 #ifdef DEVELOPER
920 /* Quieten valgrind on test. */
921 memset(&lock, '\0', sizeof(lock));
922 #endif
923
924 lock.context.smbpid = smbpid;
925 lock.context.pid = pid;
926 lock.context.tid = br_lck->fsp->conn->cnum;
927 lock.start = start;
928 lock.size = size;
929 lock.fnum = br_lck->fsp->fnum;
930 lock.lock_type = lock_type;
931 lock.lock_flav = lock_flav;
932
933 if (lock_flav == WINDOWS_LOCK) {
934 ret = SMB_VFS_BRL_LOCK_WINDOWS(br_lck->fsp->conn, br_lck,
935 &lock, blocking_lock, blr);
936 } else {
937 ret = brl_lock_posix(msg_ctx, br_lck, &lock);
938 }
939
940 #if ZERO_ZERO
941 /* sort the lock list */
942 qsort(br_lck->lock_data, (size_t)br_lck->num_locks, sizeof(lock), lock_compare);
943 #endif
944
945 /* If we're returning an error, return who blocked us. */
946 if (!NT_STATUS_IS_OK(ret) && psmbpid) {
947 *psmbpid = lock.context.smbpid;
948 }
949 return ret;
950 }
951
952 /****************************************************************************
953 Unlock a range of bytes - Windows semantics.
954 ****************************************************************************/
955
956 bool brl_unlock_windows_default(struct messaging_context *msg_ctx,
957 struct byte_range_lock *br_lck,
958 const struct lock_struct *plock)
959 {
960 unsigned int i, j;
961 struct lock_struct *locks = br_lck->lock_data;
962 enum brl_type deleted_lock_type = READ_LOCK; /* shut the compiler up.... */
963
964 SMB_ASSERT(plock->lock_type == UNLOCK_LOCK);
965
966 #if ZERO_ZERO
967 /* Delete write locks by preference... The lock list
968 is sorted in the zero zero case. */
969
970 for (i = 0; i < br_lck->num_locks; i++) {
971 struct lock_struct *lock = &locks[i];
972
973 if (lock->lock_type == WRITE_LOCK &&
974 brl_same_context(&lock->context, &plock->context) &&
975 lock->fnum == plock->fnum &&
976 lock->lock_flav == WINDOWS_LOCK &&
977 lock->start == plock->start &&
978 lock->size == plock->size) {
979
980 /* found it - delete it */
981 deleted_lock_type = lock->lock_type;
982 break;
983 }
984 }
985
986 if (i != br_lck->num_locks) {
987 /* We found it - don't search again. */
988 goto unlock_continue;
989 }
990 #endif
991
992 for (i = 0; i < br_lck->num_locks; i++) {
993 struct lock_struct *lock = &locks[i];
994
995 /* Only remove our own locks that match in start, size, and flavour. */
996 if (brl_same_context(&lock->context, &plock->context) &&
997 lock->fnum == plock->fnum &&
998 lock->lock_flav == WINDOWS_LOCK &&
999 lock->start == plock->start &&
1000 lock->size == plock->size ) {
1001 deleted_lock_type = lock->lock_type;
1002 break;
1003 }
1004 }
1005
1006 if (i == br_lck->num_locks) {
1007 /* we didn't find it */
1008 return False;
1009 }
1010
1011 #if ZERO_ZERO
1012 unlock_continue:
1013 #endif
1014
1015 /* Actually delete the lock. */
1016 if (i < br_lck->num_locks - 1) {
1017 memmove(&locks[i], &locks[i+1],
1018 sizeof(*locks)*((br_lck->num_locks-1) - i));
1019 }
1020
1021 br_lck->num_locks -= 1;
1022 br_lck->modified = True;
1023
1024 /* Unlock the underlying POSIX regions. */
1025 if(lp_posix_locking(br_lck->fsp->conn->params)) {
1026 release_posix_lock_windows_flavour(br_lck->fsp,
1027 plock->start,
1028 plock->size,
1029 deleted_lock_type,
1030 &plock->context,
1031 locks,
1032 br_lck->num_locks);
1033 }
1034
1035 /* Send unlock messages to any pending waiters that overlap. */
1036 for (j=0; j < br_lck->num_locks; j++) {
1037 struct lock_struct *pend_lock = &locks[j];
1038
1039 /* Ignore non-pending locks. */
1040 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
1041 continue;
1042 }
1043
1044 /* We could send specific lock info here... */
1045 if (brl_pending_overlap(plock, pend_lock)) {
1046 DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
1047 procid_str_static(&pend_lock->context.pid )));
1048
1049 messaging_send(msg_ctx, pend_lock->context.pid,
1050 MSG_SMB_UNLOCK, &data_blob_null);
1051 }
1052 }
1053
1054 contend_level2_oplocks_end(br_lck->fsp, LEVEL2_CONTEND_WINDOWS_BRL);
1055 return True;
1056 }
1057
1058 /****************************************************************************
1059 Unlock a range of bytes - POSIX semantics.
1060 ****************************************************************************/
1061
1062 static bool brl_unlock_posix(struct messaging_context *msg_ctx,
1063 struct byte_range_lock *br_lck,
1064 struct lock_struct *plock)
1065 {
1066 unsigned int i, j, count;
1067 struct lock_struct *tp;
1068 struct lock_struct *locks = br_lck->lock_data;
1069 bool overlap_found = False;
1070
1071 /* No zero-zero locks for POSIX. */
1072 if (plock->start == 0 && plock->size == 0) {
1073 return False;
1074 }
1075
1076 /* Don't allow 64-bit lock wrap. */
1077 if (plock->start + plock->size < plock->start ||
1078 plock->start + plock->size < plock->size) {
1079 DEBUG(10,("brl_unlock_posix: lock wrap\n"));
1080 return False;
1081 }
1082
1083 /* The worst case scenario here is we have to split an
1084 existing POSIX lock range into two, so we need at most
1085 1 more entry. */
1086
1087 tp = SMB_MALLOC_ARRAY(struct lock_struct, (br_lck->num_locks + 1));
1088 if (!tp) {
1089 DEBUG(10,("brl_unlock_posix: malloc fail\n"));
1090 return False;
1091 }
1092
1093 count = 0;
1094 for (i = 0; i < br_lck->num_locks; i++) {
1095 struct lock_struct *lock = &locks[i];
1096 unsigned int tmp_count;
1097
1098 /* Only remove our own locks - ignore fnum. */
1099 if (IS_PENDING_LOCK(lock->lock_type) ||
1100 !brl_same_context(&lock->context, &plock->context)) {
1101 memcpy(&tp[count], lock, sizeof(struct lock_struct));
1102 count++;
1103 continue;
1104 }
1105
1106 if (lock->lock_flav == WINDOWS_LOCK) {
1107 /* Do any Windows flavour locks conflict ? */
1108 if (brl_conflict(lock, plock)) {
1109 SAFE_FREE(tp);
1110 return false;
1111 }
1112 /* Just copy the Windows lock into the new array. */
1113 memcpy(&tp[count], lock, sizeof(struct lock_struct));
1114 count++;
1115 continue;
1116 }
1117
1118 /* Work out overlaps. */
1119 tmp_count = brlock_posix_split_merge(&tp[count], lock, plock);
1120
1121 if (tmp_count == 0) {
1122 /* plock overlapped the existing lock completely,
1123 or replaced it. Don't copy the existing lock. */
1124 overlap_found = true;
1125 } else if (tmp_count == 1) {
1126 /* Either no overlap, (simple copy of existing lock) or
1127 * an overlap of an existing lock. */
1128 /* If the lock changed size, we had an overlap. */
1129 if (tp[count].size != lock->size) {
1130 overlap_found = true;
1131 }
1132 count += tmp_count;
1133 } else if (tmp_count == 2) {
1134 /* We split a lock range in two. */
1135 overlap_found = true;
1136 count += tmp_count;
1137
1138 /* Optimisation... */
1139 /* We know we're finished here as we can't overlap any
1140 more POSIX locks. Copy the rest of the lock array. */
1141
1142 if (i < br_lck->num_locks - 1) {
1143 memcpy(&tp[count], &locks[i+1],
1144 sizeof(*locks)*((br_lck->num_locks-1) - i));
1145 count += ((br_lck->num_locks-1) - i);
1146 }
1147 break;
1148 }
1149
1150 }
1151
1152 if (!overlap_found) {
1153 /* Just ignore - no change. */
1154 SAFE_FREE(tp);
1155 DEBUG(10,("brl_unlock_posix: No overlap - unlocked.\n"));
1156 return True;
1157 }
1158
1159 /* Unlock any POSIX regions. */
1160 if(lp_posix_locking(br_lck->fsp->conn->params)) {
1161 release_posix_lock_posix_flavour(br_lck->fsp,
1162 plock->start,
1163 plock->size,
1164 &plock->context,
1165 tp,
1166 count);
1167 }
1168
1169 /* Realloc so we don't leak entries per unlock call. */
1170 if (count) {
1171 tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
1172 if (!tp) {
1173 DEBUG(10,("brl_unlock_posix: realloc fail\n"));
1174 return False;
1175 }
1176 } else {
1177 /* We deleted the last lock. */
1178 SAFE_FREE(tp);
1179 tp = NULL;
1180 }
1181
1182 contend_level2_oplocks_end(br_lck->fsp,
1183 LEVEL2_CONTEND_POSIX_BRL);
1184
1185 br_lck->num_locks = count;
1186 SAFE_FREE(br_lck->lock_data);
1187 locks = tp;
1188 br_lck->lock_data = tp;
1189 br_lck->modified = True;
1190
1191 /* Send unlock messages to any pending waiters that overlap. */
1192
1193 for (j=0; j < br_lck->num_locks; j++) {
1194 struct lock_struct *pend_lock = &locks[j];
1195
1196 /* Ignore non-pending locks. */
1197 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
1198 continue;
1199 }
1200
1201 /* We could send specific lock info here... */
1202 if (brl_pending_overlap(plock, pend_lock)) {
1203 DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
1204 procid_str_static(&pend_lock->context.pid )));
1205
1206 messaging_send(msg_ctx, pend_lock->context.pid,
1207 MSG_SMB_UNLOCK, &data_blob_null);
1208 }
1209 }
1210
1211 return True;
1212 }
1213
1214 bool smb_vfs_call_brl_unlock_windows(struct vfs_handle_struct *handle,
1215 struct messaging_context *msg_ctx,
1216 struct byte_range_lock *br_lck,
1217 const struct lock_struct *plock)
1218 {
1219 VFS_FIND(brl_unlock_windows);
1220 return handle->fns->brl_unlock_windows(handle, msg_ctx, br_lck, plock);
1221 }
1222
1223 /****************************************************************************
1224 Unlock a range of bytes.
1225 ****************************************************************************/
1226
1227 bool brl_unlock(struct messaging_context *msg_ctx,
1228 struct byte_range_lock *br_lck,
1229 uint32 smbpid,
1230 struct server_id pid,
1231 br_off start,
1232 br_off size,
1233 enum brl_flavour lock_flav)
1234 {
1235 struct lock_struct lock;
1236
1237 lock.context.smbpid = smbpid;
1238 lock.context.pid = pid;
1239 lock.context.tid = br_lck->fsp->conn->cnum;
1240 lock.start = start;
1241 lock.size = size;
1242 lock.fnum = br_lck->fsp->fnum;
1243 lock.lock_type = UNLOCK_LOCK;
1244 lock.lock_flav = lock_flav;
1245
1246 if (lock_flav == WINDOWS_LOCK) {
1247 return SMB_VFS_BRL_UNLOCK_WINDOWS(br_lck->fsp->conn, msg_ctx,
1248 br_lck, &lock);
1249 } else {
1250 return brl_unlock_posix(msg_ctx, br_lck, &lock);
1251 }
1252 }
1253
1254 /****************************************************************************
1255 Test if we could add a lock if we wanted to.
1256 Returns True if the region required is currently unlocked, False if locked.
1257 ****************************************************************************/
1258
1259 bool brl_locktest(struct byte_range_lock *br_lck,
1260 uint32 smbpid,
1261 struct server_id pid,
1262 br_off start,
1263 br_off size,
1264 enum brl_type lock_type,
1265 enum brl_flavour lock_flav)
1266 {
1267 bool ret = True;
1268 unsigned int i;
1269 struct lock_struct lock;
1270 const struct lock_struct *locks = br_lck->lock_data;
1271 files_struct *fsp = br_lck->fsp;
1272
1273 lock.context.smbpid = smbpid;
1274 lock.context.pid = pid;
1275 lock.context.tid = br_lck->fsp->conn->cnum;
1276 lock.start = start;
1277 lock.size = size;
1278 lock.fnum = fsp->fnum;
1279 lock.lock_type = lock_type;
1280 lock.lock_flav = lock_flav;
1281
1282 /* Make sure existing locks don't conflict */
1283 for (i=0; i < br_lck->num_locks; i++) {
1284 /*
1285 * Our own locks don't conflict.
1286 */
1287 if (brl_conflict_other(&locks[i], &lock)) {
1288 return False;
1289 }
1290 }
1291
1292 /*
1293 * There is no lock held by an SMB daemon, check to
1294 * see if there is a POSIX lock from a UNIX or NFS process.
1295 * This only conflicts with Windows locks, not POSIX locks.
1296 */
1297
1298 if(lp_posix_locking(fsp->conn->params) && (lock_flav == WINDOWS_LOCK)) {
1299 ret = is_posix_locked(fsp, &start, &size, &lock_type, WINDOWS_LOCK);
1300
1301 DEBUG(10,("brl_locktest: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
1302 (double)start, (double)size, ret ? "locked" : "unlocked",
1303 fsp->fnum, fsp_str_dbg(fsp)));
1304
1305 /* We need to return the inverse of is_posix_locked. */
1306 ret = !ret;
1307 }
1308
1309 /* no conflicts - we could have added it */
1310 return ret;
1311 }
1312
1313 /****************************************************************************
1314 Query for existing locks.
1315 ****************************************************************************/
1316
1317 NTSTATUS brl_lockquery(struct byte_range_lock *br_lck,
1318 uint32 *psmbpid,
1319 struct server_id pid,
1320 br_off *pstart,
1321 br_off *psize,
1322 enum brl_type *plock_type,
1323 enum brl_flavour lock_flav)
1324 {
1325 unsigned int i;
1326 struct lock_struct lock;
1327 const struct lock_struct *locks = br_lck->lock_data;
1328 files_struct *fsp = br_lck->fsp;
1329
1330 lock.context.smbpid = *psmbpid;
1331 lock.context.pid = pid;
1332 lock.context.tid = br_lck->fsp->conn->cnum;
1333 lock.start = *pstart;
1334 lock.size = *psize;
1335 lock.fnum = fsp->fnum;
1336 lock.lock_type = *plock_type;
1337 lock.lock_flav = lock_flav;
1338
1339 /* Make sure existing locks don't conflict */
1340 for (i=0; i < br_lck->num_locks; i++) {
1341 const struct lock_struct *exlock = &locks[i];
1342 bool conflict = False;
1343
1344 if (exlock->lock_flav == WINDOWS_LOCK) {
1345 conflict = brl_conflict(exlock, &lock);
1346 } else {
1347 conflict = brl_conflict_posix(exlock, &lock);
1348 }
1349
1350 if (conflict) {
1351 *psmbpid = exlock->context.smbpid;
1352 *pstart = exlock->start;
1353 *psize = exlock->size;
1354 *plock_type = exlock->lock_type;
1355 return NT_STATUS_LOCK_NOT_GRANTED;
1356 }
1357 }
1358
1359 /*
1360 * There is no lock held by an SMB daemon, check to
1361 * see if there is a POSIX lock from a UNIX or NFS process.
1362 */
1363
1364 if(lp_posix_locking(fsp->conn->params)) {
1365 bool ret = is_posix_locked(fsp, pstart, psize, plock_type, POSIX_LOCK);
1366
1367 DEBUG(10,("brl_lockquery: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
1368 (double)*pstart, (double)*psize, ret ? "locked" : "unlocked",
1369 fsp->fnum, fsp_str_dbg(fsp)));
1370
1371 if (ret) {
1372 /* Hmmm. No clue what to set smbpid to - use -1. */
1373 *psmbpid = 0xFFFF;
1374 return NT_STATUS_LOCK_NOT_GRANTED;
1375 }
1376 }
1377
1378 return NT_STATUS_OK;
1379 }
1380
1381
1382 bool smb_vfs_call_brl_cancel_windows(struct vfs_handle_struct *handle,
1383 struct byte_range_lock *br_lck,
1384 struct lock_struct *plock,
1385 struct blocking_lock_record *blr)
1386 {
1387 VFS_FIND(brl_cancel_windows);
1388 return handle->fns->brl_cancel_windows(handle, br_lck, plock, blr);
1389 }
1390
1391 /****************************************************************************
1392 Remove a particular pending lock.
1393 ****************************************************************************/
1394 bool brl_lock_cancel(struct byte_range_lock *br_lck,
1395 uint32 smbpid,
1396 struct server_id pid,
1397 br_off start,
1398 br_off size,
1399 enum brl_flavour lock_flav,
1400 struct blocking_lock_record *blr)
1401 {
1402 bool ret;
1403 struct lock_struct lock;
1404
1405 lock.context.smbpid = smbpid;
1406 lock.context.pid = pid;
1407 lock.context.tid = br_lck->fsp->conn->cnum;
1408 lock.start = start;
1409 lock.size = size;
1410 lock.fnum = br_lck->fsp->fnum;
1411 lock.lock_flav = lock_flav;
1412 /* lock.lock_type doesn't matter */
1413
1414 if (lock_flav == WINDOWS_LOCK) {
1415 ret = SMB_VFS_BRL_CANCEL_WINDOWS(br_lck->fsp->conn, br_lck,
1416 &lock, blr);
1417 } else {
1418 ret = brl_lock_cancel_default(br_lck, &lock);
1419 }
1420
1421 return ret;
1422 }
1423
1424 bool brl_lock_cancel_default(struct byte_range_lock *br_lck,
1425 struct lock_struct *plock)
1426 {
1427 unsigned int i;
1428 struct lock_struct *locks = br_lck->lock_data;
1429
1430 SMB_ASSERT(plock);
1431
1432 for (i = 0; i < br_lck->num_locks; i++) {
1433 struct lock_struct *lock = &locks[i];
1434
1435 /* For pending locks we *always* care about the fnum. */
1436 if (brl_same_context(&lock->context, &plock->context) &&
1437 lock->fnum == plock->fnum &&
1438 IS_PENDING_LOCK(lock->lock_type) &&
1439 lock->lock_flav == plock->lock_flav &&
1440 lock->start == plock->start &&
1441 lock->size == plock->size) {
1442 break;
1443 }
1444 }
1445
1446 if (i == br_lck->num_locks) {
1447 /* Didn't find it. */
1448 return False;
1449 }
1450
1451 if (i < br_lck->num_locks - 1) {
1452 /* Found this particular pending lock - delete it */
1453 memmove(&locks[i], &locks[i+1],
1454 sizeof(*locks)*((br_lck->num_locks-1) - i));
1455 }
1456
1457 br_lck->num_locks -= 1;
1458 br_lck->modified = True;
1459 return True;
1460 }
1461
1462 /****************************************************************************
1463 Remove any locks associated with a open file.
1464 We return True if this process owns any other Windows locks on this
1465 fd and so we should not immediately close the fd.
1466 ****************************************************************************/
1467
1468 void brl_close_fnum(struct messaging_context *msg_ctx,
1469 struct byte_range_lock *br_lck)
1470 {
1471 files_struct *fsp = br_lck->fsp;
1472 uint16 tid = fsp->conn->cnum;
1473 int fnum = fsp->fnum;
1474 unsigned int i, j, dcount=0;
1475 int num_deleted_windows_locks = 0;
1476 struct lock_struct *locks = br_lck->lock_data;
1477 struct server_id pid = procid_self();
1478 bool unlock_individually = False;
1479 bool posix_level2_contention_ended = false;
1480
1481 if(lp_posix_locking(fsp->conn->params)) {
1482
1483 /* Check if there are any Windows locks associated with this dev/ino
1484 pair that are not this fnum. If so we need to call unlock on each
1485 one in order to release the system POSIX locks correctly. */
1486
1487 for (i=0; i < br_lck->num_locks; i++) {
1488 struct lock_struct *lock = &locks[i];
1489
1490 if (!procid_equal(&lock->context.pid, &pid)) {
1491 continue;
1492 }
1493
1494 if (lock->lock_type != READ_LOCK && lock->lock_type != WRITE_LOCK) {
1495 continue; /* Ignore pending. */
1496 }
1497
1498 if (lock->context.tid != tid || lock->fnum != fnum) {
1499 unlock_individually = True;
1500 break;
1501 }
1502 }
1503
1504 if (unlock_individually) {
1505 struct lock_struct *locks_copy;
1506 unsigned int num_locks_copy;
1507
1508 /* Copy the current lock array. */
1509 if (br_lck->num_locks) {
1510 locks_copy = (struct lock_struct *)TALLOC_MEMDUP(br_lck, locks, br_lck->num_locks * sizeof(struct lock_struct));
1511 if (!locks_copy) {
1512 smb_panic("brl_close_fnum: talloc failed");
1513 }
1514 } else {
1515 locks_copy = NULL;
1516 }
1517
1518 num_locks_copy = br_lck->num_locks;
1519
1520 for (i=0; i < num_locks_copy; i++) {
1521 struct lock_struct *lock = &locks_copy[i];
1522
1523 if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid) &&
1524 (lock->fnum == fnum)) {
1525 brl_unlock(msg_ctx,
1526 br_lck,
1527 lock->context.smbpid,
1528 pid,
1529 lock->start,
1530 lock->size,
1531 lock->lock_flav);
1532 }
1533 }
1534 return;
1535 }
1536 }
1537
1538 /* We can bulk delete - any POSIX locks will be removed when the fd closes. */
1539
1540 /* Remove any existing locks for this fnum (or any fnum if they're POSIX). */
1541
1542 for (i=0; i < br_lck->num_locks; i++) {
1543 struct lock_struct *lock = &locks[i];
1544 bool del_this_lock = False;
1545
1546 if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid)) {
1547 if ((lock->lock_flav == WINDOWS_LOCK) && (lock->fnum == fnum)) {
1548 del_this_lock = True;
1549 num_deleted_windows_locks++;
1550 contend_level2_oplocks_end(br_lck->fsp,
1551 LEVEL2_CONTEND_WINDOWS_BRL);
1552 } else if (lock->lock_flav == POSIX_LOCK) {
1553 del_this_lock = True;
1554
1555 /* Only end level2 contention once for posix */
1556 if (!posix_level2_contention_ended) {
1557 posix_level2_contention_ended = true;
1558 contend_level2_oplocks_end(br_lck->fsp,
1559 LEVEL2_CONTEND_POSIX_BRL);
1560 }
1561 }
1562 }
1563
1564 if (del_this_lock) {
1565 /* Send unlock messages to any pending waiters that overlap. */
1566 for (j=0; j < br_lck->num_locks; j++) {
1567 struct lock_struct *pend_lock = &locks[j];
1568
1569 /* Ignore our own or non-pending locks. */
1570 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
1571 continue;
1572 }
1573
1574 /* Optimisation - don't send to this fnum as we're
1575 closing it. */
1576 if (pend_lock->context.tid == tid &&
1577 procid_equal(&pend_lock->context.pid, &pid) &&
1578 pend_lock->fnum == fnum) {
1579 continue;
1580 }
1581
1582 /* We could send specific lock info here... */
1583 if (brl_pending_overlap(lock, pend_lock)) {
1584 messaging_send(msg_ctx, pend_lock->context.pid,
1585 MSG_SMB_UNLOCK, &data_blob_null);
1586 }
1587 }
1588
1589 /* found it - delete it */
1590 if (br_lck->num_locks > 1 && i < br_lck->num_locks - 1) {
1591 memmove(&locks[i], &locks[i+1],
1592 sizeof(*locks)*((br_lck->num_locks-1) - i));
1593 }
1594 br_lck->num_locks--;
1595 br_lck->modified = True;
1596 i--;
1597 dcount++;
1598 }
1599 }
1600
1601 if(lp_posix_locking(fsp->conn->params) && num_deleted_windows_locks) {
1602 /* Reduce the Windows lock POSIX reference count on this dev/ino pair. */
1603 reduce_windows_lock_ref_count(fsp, num_deleted_windows_locks);
1604 }
1605 }
1606
1607 /****************************************************************************
1608 Ensure this set of lock entries is valid.
1609 ****************************************************************************/
1610 static bool validate_lock_entries(unsigned int *pnum_entries, struct lock_struct **pplocks)
1611 {
1612 unsigned int i;
1613 unsigned int num_valid_entries = 0;
1614 struct lock_struct *locks = *pplocks;
1615
1616 for (i = 0; i < *pnum_entries; i++) {
1617 struct lock_struct *lock_data = &locks[i];
1618 if (!process_exists(lock_data->context.pid)) {
1619 /* This process no longer exists - mark this
1620 entry as invalid by zeroing it. */
1621 ZERO_STRUCTP(lock_data);
1622 } else {
1623 num_valid_entries++;
1624 }
1625 }
1626
1627 if (num_valid_entries != *pnum_entries) {
1628 struct lock_struct *new_lock_data = NULL;
1629
1630 if (num_valid_entries) {
1631 new_lock_data = SMB_MALLOC_ARRAY(struct lock_struct, num_valid_entries);
1632 if (!new_lock_data) {
1633 DEBUG(3, ("malloc fail\n"));
1634 return False;
1635 }
1636
1637 num_valid_entries = 0;
1638 for (i = 0; i < *pnum_entries; i++) {
1639 struct lock_struct *lock_data = &locks[i];
1640 if (lock_data->context.smbpid &&
1641 lock_data->context.tid) {
1642 /* Valid (nonzero) entry - copy it. */
1643 memcpy(&new_lock_data[num_valid_entries],
1644 lock_data, sizeof(struct lock_struct));
1645 num_valid_entries++;
1646 }
1647 }
1648 }
1649
1650 SAFE_FREE(*pplocks);
1651 *pplocks = new_lock_data;
1652 *pnum_entries = num_valid_entries;
1653 }
1654
1655 return True;
1656 }
1657
1658 struct brl_forall_cb {
1659 void (*fn)(struct file_id id, struct server_id pid,
1660 enum brl_type lock_type,
1661 enum brl_flavour lock_flav,
1662 br_off start, br_off size,
1663 void *private_data);
1664 void *private_data;
1665 };
1666
1667 /****************************************************************************
1668 Traverse the whole database with this function, calling traverse_callback
1669 on each lock.
1670 ****************************************************************************/
1671
1672 static int traverse_fn(struct db_record *rec, void *state)
1673 {
1674 struct brl_forall_cb *cb = (struct brl_forall_cb *)state;
1675 struct lock_struct *locks;
1676 struct file_id *key;
1677 unsigned int i;
1678 unsigned int num_locks = 0;
1679 unsigned int orig_num_locks = 0;
1680
1681 /* In a traverse function we must make a copy of
1682 dbuf before modifying it. */
1683
1684 locks = (struct lock_struct *)memdup(rec->value.dptr,
1685 rec->value.dsize);
1686 if (!locks) {
1687 return -1; /* Terminate traversal. */
1688 }
1689
1690 key = (struct file_id *)rec->key.dptr;
1691 orig_num_locks = num_locks = rec->value.dsize/sizeof(*locks);
1692
1693 /* Ensure the lock db is clean of entries from invalid processes. */
1694
1695 if (!validate_lock_entries(&num_locks, &locks)) {
1696 SAFE_FREE(locks);
1697 return -1; /* Terminate traversal */
1698 }
1699
1700 if (orig_num_locks != num_locks) {
1701 if (num_locks) {
1702 TDB_DATA data;
1703 data.dptr = (uint8_t *)locks;
1704 data.dsize = num_locks*sizeof(struct lock_struct);
1705 rec->store(rec, data, TDB_REPLACE);
1706 } else {
1707 rec->delete_rec(rec);
1708 }
1709 }
1710
1711 if (cb->fn) {
1712 for ( i=0; i<num_locks; i++) {
1713 cb->fn(*key,
1714 locks[i].context.pid,
1715 locks[i].lock_type,
1716 locks[i].lock_flav,
1717 locks[i].start,
1718 locks[i].size,
1719 cb->private_data);
1720 }
1721 }
1722
1723 SAFE_FREE(locks);
1724 return 0;
1725 }
1726
1727 /*******************************************************************
1728 Call the specified function on each lock in the database.
1729 ********************************************************************/
1730
1731 int brl_forall(void (*fn)(struct file_id id, struct server_id pid,
1732 enum brl_type lock_type,
1733 enum brl_flavour lock_flav,
1734 br_off start, br_off size,
1735 void *private_data),
1736 void *private_data)
1737 {
1738 struct brl_forall_cb cb;
1739
1740 if (!brlock_db) {
1741 return 0;
1742 }
1743 cb.fn = fn;
1744 cb.private_data = private_data;
1745 return brlock_db->traverse(brlock_db, traverse_fn, &cb);
1746 }
1747
1748 /*******************************************************************
1749 Store a potentially modified set of byte range lock data back into
1750 the database.
1751 Unlock the record.
1752 ********************************************************************/
1753
1754 static int byte_range_lock_destructor(struct byte_range_lock *br_lck)
1755 {
1756 if (br_lck->read_only) {
1757 SMB_ASSERT(!br_lck->modified);
1758 }
1759
1760 if (!br_lck->modified) {
1761 goto done;
1762 }
1763
1764 if (br_lck->num_locks == 0) {
1765 /* No locks - delete this entry. */
1766 NTSTATUS status = br_lck->record->delete_rec(br_lck->record);
1767 if (!NT_STATUS_IS_OK(status)) {
1768 DEBUG(0, ("delete_rec returned %s\n",
1769 nt_errstr(status)));
1770 smb_panic("Could not delete byte range lock entry");
1771 }
1772 } else {
1773 TDB_DATA data;
1774 NTSTATUS status;
1775
1776 data.dptr = (uint8 *)br_lck->lock_data;
1777 data.dsize = br_lck->num_locks * sizeof(struct lock_struct);
1778
1779 status = br_lck->record->store(br_lck->record, data,
1780 TDB_REPLACE);
1781 if (!NT_STATUS_IS_OK(status)) {
1782 DEBUG(0, ("store returned %s\n", nt_errstr(status)));
1783 smb_panic("Could not store byte range mode entry");
1784 }
1785 }
1786
1787 done:
1788
1789 SAFE_FREE(br_lck->lock_data);
1790 TALLOC_FREE(br_lck->record);
1791 return 0;
1792 }
1793
1794 /*******************************************************************
1795 Fetch a set of byte range lock data from the database.
1796 Leave the record locked.
1797 TALLOC_FREE(brl) will release the lock in the destructor.
1798 ********************************************************************/
1799
1800 static struct byte_range_lock *brl_get_locks_internal(TALLOC_CTX *mem_ctx,
1801 files_struct *fsp, bool read_only)
1802 {
1803 TDB_DATA key, data;
1804 struct byte_range_lock *br_lck = TALLOC_P(mem_ctx, struct byte_range_lock);
1805
1806 if (br_lck == NULL) {
1807 return NULL;
1808 }
1809
1810 br_lck->fsp = fsp;
1811 br_lck->num_locks = 0;
1812 br_lck->modified = False;
1813 br_lck->key = fsp->file_id;
1814
1815 key.dptr = (uint8 *)&br_lck->key;
1816 key.dsize = sizeof(struct file_id);
1817
1818 if (!fsp->lockdb_clean) {
1819 /* We must be read/write to clean
1820 the dead entries. */
1821 read_only = False;
1822 }
1823
1824 if (read_only) {
1825 if (brlock_db->fetch(brlock_db, br_lck, key, &data) == -1) {
1826 DEBUG(3, ("Could not fetch byte range lock record\n"));
1827 TALLOC_FREE(br_lck);
1828 return NULL;
1829 }
1830 br_lck->record = NULL;
1831 }
1832 else {
1833 br_lck->record = brlock_db->fetch_locked(brlock_db, br_lck, key);
1834
1835 if (br_lck->record == NULL) {
1836 DEBUG(3, ("Could not lock byte range lock entry\n"));
1837 TALLOC_FREE(br_lck);
1838 return NULL;
1839 }
1840
1841 data = br_lck->record->value;
1842 }
1843
1844 br_lck->read_only = read_only;
1845 br_lck->lock_data = NULL;
1846
1847 talloc_set_destructor(br_lck, byte_range_lock_destructor);
1848
1849 br_lck->num_locks = data.dsize / sizeof(struct lock_struct);
1850
1851 if (br_lck->num_locks != 0) {
1852 br_lck->lock_data = SMB_MALLOC_ARRAY(struct lock_struct,
1853 br_lck->num_locks);
1854 if (br_lck->lock_data == NULL) {
1855 DEBUG(0, ("malloc failed\n"));
1856 TALLOC_FREE(br_lck);
1857 return NULL;
1858 }
1859
1860 memcpy(br_lck->lock_data, data.dptr, data.dsize);
1861 }
1862
1863 if (!fsp->lockdb_clean) {
1864 int orig_num_locks = br_lck->num_locks;
1865
1866 /* This is the first time we've accessed this. */
1867 /* Go through and ensure all entries exist - remove any that don't. */
1868 /* Makes the lockdb self cleaning at low cost. */
1869
1870 if (!validate_lock_entries(&br_lck->num_locks,
1871 &br_lck->lock_data)) {
1872 SAFE_FREE(br_lck->lock_data);
1873 TALLOC_FREE(br_lck);
1874 return NULL;
1875 }
1876
1877 /* Ensure invalid locks are cleaned up in the destructor. */
1878 if (orig_num_locks != br_lck->num_locks) {
1879 br_lck->modified = True;
1880 }
1881
1882 /* Mark the lockdb as "clean" as seen from this open file. */
1883 fsp->lockdb_clean = True;
1884 }
1885
1886 if (DEBUGLEVEL >= 10) {
1887 unsigned int i;
1888 struct lock_struct *locks = br_lck->lock_data;
1889 DEBUG(10,("brl_get_locks_internal: %u current locks on file_id %s\n",
1890 br_lck->num_locks,
1891 file_id_string_tos(&fsp->file_id)));
1892 for( i = 0; i < br_lck->num_locks; i++) {
1893 print_lock_struct(i, &locks[i]);
1894 }
1895 }
1896 return br_lck;
1897 }
1898
1899 struct byte_range_lock *brl_get_locks(TALLOC_CTX *mem_ctx,
1900 files_struct *fsp)
1901 {
1902 return brl_get_locks_internal(mem_ctx, fsp, False);
1903 }
1904
1905 struct byte_range_lock *brl_get_locks_readonly(files_struct *fsp)
1906 {
1907 struct byte_range_lock *br_lock;
1908
1909 if (lp_clustering()) {
1910 return brl_get_locks_internal(talloc_tos(), fsp, true);
1911 }
1912
1913 if ((fsp->brlock_rec != NULL)
1914 && (brlock_db->get_seqnum(brlock_db) == fsp->brlock_seqnum)) {
1915 return fsp->brlock_rec;
1916 }
1917
1918 TALLOC_FREE(fsp->brlock_rec);
1919
1920 br_lock = brl_get_locks_internal(talloc_tos(), fsp, false);
1921 if (br_lock == NULL) {
1922 return NULL;
1923 }
1924 fsp->brlock_seqnum = brlock_db->get_seqnum(brlock_db);
1925
1926 fsp->brlock_rec = talloc_zero(fsp, struct byte_range_lock);
1927 if (fsp->brlock_rec == NULL) {
1928 goto fail;
1929 }
1930 fsp->brlock_rec->fsp = fsp;
1931 fsp->brlock_rec->num_locks = br_lock->num_locks;
1932 fsp->brlock_rec->read_only = true;
1933 fsp->brlock_rec->key = br_lock->key;
1934
1935 fsp->brlock_rec->lock_data = (struct lock_struct *)
1936 talloc_memdup(fsp->brlock_rec, br_lock->lock_data,
1937 sizeof(struct lock_struct) * br_lock->num_locks);
1938 if (fsp->brlock_rec->lock_data == NULL) {
1939 goto fail;
1940 }
1941
1942 TALLOC_FREE(br_lock);
1943 return fsp->brlock_rec;
1944 fail:
1945 TALLOC_FREE(br_lock);
1946 TALLOC_FREE(fsp->brlock_rec);
1947 return NULL;
1948 }
1949
1950 struct brl_revalidate_state {
1951 ssize_t array_size;
1952 uint32 num_pids;
1953 struct server_id *pids;
1954 };
1955
1956 /*
1957 * Collect PIDs of all processes with pending entries
1958 */
1959
1960 static void brl_revalidate_collect(struct file_id id, struct server_id pid,
1961 enum brl_type lock_type,
1962 enum brl_flavour lock_flav,
1963 br_off start, br_off size,
1964 void *private_data)
1965 {
1966 struct brl_revalidate_state *state =
1967 (struct brl_revalidate_state *)private_data;
1968
1969 if (!IS_PENDING_LOCK(lock_type)) {
1970 return;
1971 }
1972
1973 add_to_large_array(state, sizeof(pid), (void *)&pid,
1974 &state->pids, &state->num_pids,
1975 &state->array_size);
1976 }
1977
1978 /*
1979 * qsort callback to sort the processes
1980 */
1981
1982 static int compare_procids(const void *p1, const void *p2)
1983 {
1984 const struct server_id *i1 = (struct server_id *)p1;
1985 const struct server_id *i2 = (struct server_id *)p2;
1986
1987 if (i1->pid < i2->pid) return -1;
1988 if (i2->pid > i2->pid) return 1;
1989 return 0;
1990 }
1991
1992 /*
1993 * Send a MSG_SMB_UNLOCK message to all processes with pending byte range
1994 * locks so that they retry. Mainly used in the cluster code after a node has
1995 * died.
1996 *
1997 * Done in two steps to avoid double-sends: First we collect all entries in an
1998 * array, then qsort that array and only send to non-dupes.
1999 */
2000
2001 static void brl_revalidate(struct messaging_context *msg_ctx,
2002 void *private_data,
2003 uint32_t msg_type,
2004 struct server_id server_id,
2005 DATA_BLOB *data)
2006 {
2007 struct brl_revalidate_state *state;
2008 uint32 i;
2009 struct server_id last_pid;
2010
2011 if (!(state = TALLOC_ZERO_P(NULL, struct brl_revalidate_state))) {
2012 DEBUG(0, ("talloc failed\n"));
2013 return;
2014 }
2015
2016 brl_forall(brl_revalidate_collect, state);
2017
2018 if (state->array_size == -1) {
2019 DEBUG(0, ("talloc failed\n"));
2020 goto done;
2021 }
2022
2023 if (state->num_pids == 0) {
2024 goto done;
2025 }
2026
2027 qsort(state->pids, state->num_pids, sizeof(state->pids[0]),
2028 compare_procids);
2029
2030 ZERO_STRUCT(last_pid);
2031
2032 for (i=0; i<state->num_pids; i++) {
2033 if (procid_equal(&last_pid, &state->pids[i])) {
2034 /*
2035 * We've seen that one already
2036 */
2037 continue;
2038 }
2039
2040 messaging_send(msg_ctx, state->pids[i], MSG_SMB_UNLOCK,
2041 &data_blob_null);
2042 last_pid = state->pids[i];
2043 }
2044
2045 done:
2046 TALLOC_FREE(state);
2047 return;
2048 }
2049
2050 void brl_register_msgs(struct messaging_context *msg_ctx)
2051 {
2052 messaging_register(msg_ctx, NULL, MSG_SMB_BRL_VALIDATE,
2053 brl_revalidate);
2054 }
fernandojvsilva's samba4 branch