source: branches/samba-3.2.x/source/locking/brlock.c@ 1001

Last change on this file since 1001 was 133, checked in by Paul Smedley, 17 years ago

Update trunk to 3.2.0pre3
File size: 49.9 KB
Line 
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
36static struct db_context *brlock_db;
37
38/****************************************************************************
39 Debug info at level 10 for lock struct.
40****************************************************************************/
41
42static 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
62bool 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
74static 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
96static 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
122static 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
150static 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
184static 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
216static 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
231static 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
261void 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_VOLATILE|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
281void brl_shutdown(void)
282{
283 TALLOC_FREE(brlock_db);
284}
285
286#if ZERO_ZERO
287/****************************************************************************
288 Compare two locks for sorting.
289****************************************************************************/
290
291static 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
308static 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
374static 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 +-------+
400OR....
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 +---------------+
436OR....
437 +-------+
438 | ex |
439 +-------+
440 +---------------+
441 | plock |
442 +---------------+
443
444BECOMES....
445 +---------------+-------+
446 | plock | ex | - different lock types.
447 +---------------+-------+
448OR.... (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 +---------------+
488OR....
489 +-------+
490 | ex |
491 +-------+
492 +---------------+
493 | plock |
494 +---------------+
495BECOMES....
496 +-------+---------------+
497 | ex | plock | - different lock types
498 +-------+---------------+
499
500OR.... (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 +---------+
538BECOMES.....
539 +-------+---------+---------+
540 | ex | plock | ex | - different lock types.
541 +-------+---------+---------+
542OR
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
586static 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
732NTSTATUS 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#ifdef DEVELOPER
753 /* Quieten valgrind on test. */
754 memset(&lock, '\0', sizeof(lock));
755#endif
756
757 lock.context.smbpid = smbpid;
758 lock.context.pid = pid;
759 lock.context.tid = br_lck->fsp->conn->cnum;
760 lock.start = start;
761 lock.size = size;
762 lock.fnum = br_lck->fsp->fnum;
763 lock.lock_type = lock_type;
764 lock.lock_flav = lock_flav;
765
766 if (lock_flav == WINDOWS_LOCK) {
767 ret = brl_lock_windows(br_lck, &lock, blocking_lock);
768 } else {
769 ret = brl_lock_posix(msg_ctx, br_lck, &lock);
770 }
771
772#if ZERO_ZERO
773 /* sort the lock list */
774 qsort(br_lck->lock_data, (size_t)br_lck->num_locks, sizeof(lock), lock_compare);
775#endif
776
777 /* If we're returning an error, return who blocked us. */
778 if (!NT_STATUS_IS_OK(ret) && psmbpid) {
779 *psmbpid = lock.context.smbpid;
780 }
781 return ret;
782}
783
784/****************************************************************************
785 Unlock a range of bytes - Windows semantics.
786****************************************************************************/
787
788static bool brl_unlock_windows(struct messaging_context *msg_ctx,
789 struct byte_range_lock *br_lck,
790 const struct lock_struct *plock)
791{
792 unsigned int i, j;
793 struct lock_struct *locks = br_lck->lock_data;
794 enum brl_type deleted_lock_type = READ_LOCK; /* shut the compiler up.... */
795
796#if ZERO_ZERO
797 /* Delete write locks by preference... The lock list
798 is sorted in the zero zero case. */
799
800 for (i = 0; i < br_lck->num_locks; i++) {
801 struct lock_struct *lock = &locks[i];
802
803 if (lock->lock_type == WRITE_LOCK &&
804 brl_same_context(&lock->context, &plock->context) &&
805 lock->fnum == plock->fnum &&
806 lock->lock_flav == WINDOWS_LOCK &&
807 lock->start == plock->start &&
808 lock->size == plock->size) {
809
810 /* found it - delete it */
811 deleted_lock_type = lock->lock_type;
812 break;
813 }
814 }
815
816 if (i != br_lck->num_locks) {
817 /* We found it - don't search again. */
818 goto unlock_continue;
819 }
820#endif
821
822 for (i = 0; i < br_lck->num_locks; i++) {
823 struct lock_struct *lock = &locks[i];
824
825 /* Only remove our own locks that match in start, size, and flavour. */
826 if (brl_same_context(&lock->context, &plock->context) &&
827 lock->fnum == plock->fnum &&
828 lock->lock_flav == WINDOWS_LOCK &&
829 lock->start == plock->start &&
830 lock->size == plock->size ) {
831 deleted_lock_type = lock->lock_type;
832 break;
833 }
834 }
835
836 if (i == br_lck->num_locks) {
837 /* we didn't find it */
838 return False;
839 }
840
841#if ZERO_ZERO
842 unlock_continue:
843#endif
844
845 /* Actually delete the lock. */
846 if (i < br_lck->num_locks - 1) {
847 memmove(&locks[i], &locks[i+1],
848 sizeof(*locks)*((br_lck->num_locks-1) - i));
849 }
850
851 br_lck->num_locks -= 1;
852 br_lck->modified = True;
853
854 /* Unlock the underlying POSIX regions. */
855 if(lp_posix_locking(br_lck->fsp->conn->params)) {
856 release_posix_lock_windows_flavour(br_lck->fsp,
857 plock->start,
858 plock->size,
859 deleted_lock_type,
860 &plock->context,
861 locks,
862 br_lck->num_locks);
863 }
864
865 /* Send unlock messages to any pending waiters that overlap. */
866 for (j=0; j < br_lck->num_locks; j++) {
867 struct lock_struct *pend_lock = &locks[j];
868
869 /* Ignore non-pending locks. */
870 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
871 continue;
872 }
873
874 /* We could send specific lock info here... */
875 if (brl_pending_overlap(plock, pend_lock)) {
876 DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
877 procid_str_static(&pend_lock->context.pid )));
878
879 messaging_send(msg_ctx, pend_lock->context.pid,
880 MSG_SMB_UNLOCK, &data_blob_null);
881 }
882 }
883
884 return True;
885}
886
887/****************************************************************************
888 Unlock a range of bytes - POSIX semantics.
889****************************************************************************/
890
891static bool brl_unlock_posix(struct messaging_context *msg_ctx,
892 struct byte_range_lock *br_lck,
893 const struct lock_struct *plock)
894{
895 unsigned int i, j, count;
896 struct lock_struct *tp;
897 struct lock_struct *locks = br_lck->lock_data;
898 bool overlap_found = False;
899
900 /* No zero-zero locks for POSIX. */
901 if (plock->start == 0 && plock->size == 0) {
902 return False;
903 }
904
905 /* Don't allow 64-bit lock wrap. */
906 if (plock->start + plock->size < plock->start ||
907 plock->start + plock->size < plock->size) {
908 DEBUG(10,("brl_unlock_posix: lock wrap\n"));
909 return False;
910 }
911
912 /* The worst case scenario here is we have to split an
913 existing POSIX lock range into two, so we need at most
914 1 more entry. */
915
916 tp = SMB_MALLOC_ARRAY(struct lock_struct, (br_lck->num_locks + 1));
917 if (!tp) {
918 DEBUG(10,("brl_unlock_posix: malloc fail\n"));
919 return False;
920 }
921
922 count = 0;
923 for (i = 0; i < br_lck->num_locks; i++) {
924 struct lock_struct *lock = &locks[i];
925 struct lock_struct tmp_lock[3];
926 bool lock_was_added = False;
927 unsigned int tmp_count;
928
929 /* Only remove our own locks - ignore fnum. */
930 if (IS_PENDING_LOCK(lock->lock_type) ||
931 !brl_same_context(&lock->context, &plock->context)) {
932 memcpy(&tp[count], lock, sizeof(struct lock_struct));
933 count++;
934 continue;
935 }
936
937 /* Work out overlaps. */
938 tmp_count = brlock_posix_split_merge(&tmp_lock[0], &locks[i], plock, &lock_was_added);
939
940 if (tmp_count == 1) {
941 /* Ether the locks didn't overlap, or the unlock completely
942 overlapped this lock. If it didn't overlap, then there's
943 no change in the locks. */
944 if (tmp_lock[0].lock_type != UNLOCK_LOCK) {
945 SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
946 /* No change in this lock. */
947 memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
948 count++;
949 } else {
950 SMB_ASSERT(tmp_lock[0].lock_type == UNLOCK_LOCK);
951 overlap_found = True;
952 }
953 continue;
954 } else if (tmp_count == 2) {
955 /* The unlock overlapped an existing lock. Copy the truncated
956 lock into the lock array. */
957 if (tmp_lock[0].lock_type != UNLOCK_LOCK) {
958 SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
959 SMB_ASSERT(tmp_lock[1].lock_type == UNLOCK_LOCK);
960 memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
961 if (tmp_lock[0].size != locks[i].size) {
962 overlap_found = True;
963 }
964 } else {
965 SMB_ASSERT(tmp_lock[0].lock_type == UNLOCK_LOCK);
966 SMB_ASSERT(tmp_lock[1].lock_type == locks[i].lock_type);
967 memcpy(&tp[count], &tmp_lock[1], sizeof(struct lock_struct));
968 if (tmp_lock[1].start != locks[i].start) {
969 overlap_found = True;
970 }
971 }
972 count++;
973 continue;
974 } else {
975 /* tmp_count == 3 - (we split a lock range in two). */
976 SMB_ASSERT(tmp_lock[0].lock_type == locks[i].lock_type);
977 SMB_ASSERT(tmp_lock[1].lock_type == UNLOCK_LOCK);
978 SMB_ASSERT(tmp_lock[2].lock_type == locks[i].lock_type);
979
980 memcpy(&tp[count], &tmp_lock[0], sizeof(struct lock_struct));
981 count++;
982 memcpy(&tp[count], &tmp_lock[2], sizeof(struct lock_struct));
983 count++;
984 overlap_found = True;
985 /* Optimisation... */
986 /* We know we're finished here as we can't overlap any
987 more POSIX locks. Copy the rest of the lock array. */
988 if (i < br_lck->num_locks - 1) {
989 memcpy(&tp[count], &locks[i+1],
990 sizeof(*locks)*((br_lck->num_locks-1) - i));
991 count += ((br_lck->num_locks-1) - i);
992 }
993 break;
994 }
995 }
996
997 if (!overlap_found) {
998 /* Just ignore - no change. */
999 SAFE_FREE(tp);
1000 DEBUG(10,("brl_unlock_posix: No overlap - unlocked.\n"));
1001 return True;
1002 }
1003
1004 /* Unlock any POSIX regions. */
1005 if(lp_posix_locking(br_lck->fsp->conn->params)) {
1006 release_posix_lock_posix_flavour(br_lck->fsp,
1007 plock->start,
1008 plock->size,
1009 &plock->context,
1010 tp,
1011 count);
1012 }
1013
1014 /* Realloc so we don't leak entries per unlock call. */
1015 if (count) {
1016 tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
1017 if (!tp) {
1018 DEBUG(10,("brl_unlock_posix: realloc fail\n"));
1019 return False;
1020 }
1021 } else {
1022 /* We deleted the last lock. */
1023 SAFE_FREE(tp);
1024 tp = NULL;
1025 }
1026
1027 br_lck->num_locks = count;
1028 SAFE_FREE(br_lck->lock_data);
1029 locks = tp;
1030 br_lck->lock_data = tp;
1031 br_lck->modified = True;
1032
1033 /* Send unlock messages to any pending waiters that overlap. */
1034
1035 for (j=0; j < br_lck->num_locks; j++) {
1036 struct lock_struct *pend_lock = &locks[j];
1037
1038 /* Ignore non-pending locks. */
1039 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
1040 continue;
1041 }
1042
1043 /* We could send specific lock info here... */
1044 if (brl_pending_overlap(plock, pend_lock)) {
1045 DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
1046 procid_str_static(&pend_lock->context.pid )));
1047
1048 messaging_send(msg_ctx, pend_lock->context.pid,
1049 MSG_SMB_UNLOCK, &data_blob_null);
1050 }
1051 }
1052
1053 return True;
1054}
1055
1056/****************************************************************************
1057 Unlock a range of bytes.
1058****************************************************************************/
1059
1060bool brl_unlock(struct messaging_context *msg_ctx,
1061 struct byte_range_lock *br_lck,
1062 uint32 smbpid,
1063 struct server_id pid,
1064 br_off start,
1065 br_off size,
1066 enum brl_flavour lock_flav)
1067{
1068 struct lock_struct lock;
1069
1070 lock.context.smbpid = smbpid;
1071 lock.context.pid = pid;
1072 lock.context.tid = br_lck->fsp->conn->cnum;
1073 lock.start = start;
1074 lock.size = size;
1075 lock.fnum = br_lck->fsp->fnum;
1076 lock.lock_type = UNLOCK_LOCK;
1077 lock.lock_flav = lock_flav;
1078
1079 if (lock_flav == WINDOWS_LOCK) {
1080 return brl_unlock_windows(msg_ctx, br_lck, &lock);
1081 } else {
1082 return brl_unlock_posix(msg_ctx, br_lck, &lock);
1083 }
1084}
1085
1086/****************************************************************************
1087 Test if we could add a lock if we wanted to.
1088 Returns True if the region required is currently unlocked, False if locked.
1089****************************************************************************/
1090
1091bool brl_locktest(struct byte_range_lock *br_lck,
1092 uint32 smbpid,
1093 struct server_id pid,
1094 br_off start,
1095 br_off size,
1096 enum brl_type lock_type,
1097 enum brl_flavour lock_flav)
1098{
1099 bool ret = True;
1100 unsigned int i;
1101 struct lock_struct lock;
1102 const struct lock_struct *locks = br_lck->lock_data;
1103 files_struct *fsp = br_lck->fsp;
1104
1105 lock.context.smbpid = smbpid;
1106 lock.context.pid = pid;
1107 lock.context.tid = br_lck->fsp->conn->cnum;
1108 lock.start = start;
1109 lock.size = size;
1110 lock.fnum = fsp->fnum;
1111 lock.lock_type = lock_type;
1112 lock.lock_flav = lock_flav;
1113
1114 /* Make sure existing locks don't conflict */
1115 for (i=0; i < br_lck->num_locks; i++) {
1116 /*
1117 * Our own locks don't conflict.
1118 */
1119 if (brl_conflict_other(&locks[i], &lock)) {
1120 return False;
1121 }
1122 }
1123
1124 /*
1125 * There is no lock held by an SMB daemon, check to
1126 * see if there is a POSIX lock from a UNIX or NFS process.
1127 * This only conflicts with Windows locks, not POSIX locks.
1128 */
1129
1130 if(lp_posix_locking(fsp->conn->params) && (lock_flav == WINDOWS_LOCK)) {
1131 ret = is_posix_locked(fsp, &start, &size, &lock_type, WINDOWS_LOCK);
1132
1133 DEBUG(10,("brl_locktest: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
1134 (double)start, (double)size, ret ? "locked" : "unlocked",
1135 fsp->fnum, fsp->fsp_name ));
1136
1137 /* We need to return the inverse of is_posix_locked. */
1138 ret = !ret;
1139 }
1140
1141 /* no conflicts - we could have added it */
1142 return ret;
1143}
1144
1145/****************************************************************************
1146 Query for existing locks.
1147****************************************************************************/
1148
1149NTSTATUS brl_lockquery(struct byte_range_lock *br_lck,
1150 uint32 *psmbpid,
1151 struct server_id pid,
1152 br_off *pstart,
1153 br_off *psize,
1154 enum brl_type *plock_type,
1155 enum brl_flavour lock_flav)
1156{
1157 unsigned int i;
1158 struct lock_struct lock;
1159 const struct lock_struct *locks = br_lck->lock_data;
1160 files_struct *fsp = br_lck->fsp;
1161
1162 lock.context.smbpid = *psmbpid;
1163 lock.context.pid = pid;
1164 lock.context.tid = br_lck->fsp->conn->cnum;
1165 lock.start = *pstart;
1166 lock.size = *psize;
1167 lock.fnum = fsp->fnum;
1168 lock.lock_type = *plock_type;
1169 lock.lock_flav = lock_flav;
1170
1171 /* Make sure existing locks don't conflict */
1172 for (i=0; i < br_lck->num_locks; i++) {
1173 const struct lock_struct *exlock = &locks[i];
1174 bool conflict = False;
1175
1176 if (exlock->lock_flav == WINDOWS_LOCK) {
1177 conflict = brl_conflict(exlock, &lock);
1178 } else {
1179 conflict = brl_conflict_posix(exlock, &lock);
1180 }
1181
1182 if (conflict) {
1183 *psmbpid = exlock->context.smbpid;
1184 *pstart = exlock->start;
1185 *psize = exlock->size;
1186 *plock_type = exlock->lock_type;
1187 return NT_STATUS_LOCK_NOT_GRANTED;
1188 }
1189 }
1190
1191 /*
1192 * There is no lock held by an SMB daemon, check to
1193 * see if there is a POSIX lock from a UNIX or NFS process.
1194 */
1195
1196 if(lp_posix_locking(fsp->conn->params)) {
1197 bool ret = is_posix_locked(fsp, pstart, psize, plock_type, POSIX_LOCK);
1198
1199 DEBUG(10,("brl_lockquery: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
1200 (double)*pstart, (double)*psize, ret ? "locked" : "unlocked",
1201 fsp->fnum, fsp->fsp_name ));
1202
1203 if (ret) {
1204 /* Hmmm. No clue what to set smbpid to - use -1. */
1205 *psmbpid = 0xFFFF;
1206 return NT_STATUS_LOCK_NOT_GRANTED;
1207 }
1208 }
1209
1210 return NT_STATUS_OK;
1211}
1212
1213/****************************************************************************
1214 Remove a particular pending lock.
1215****************************************************************************/
1216
1217bool brl_lock_cancel(struct byte_range_lock *br_lck,
1218 uint32 smbpid,
1219 struct server_id pid,
1220 br_off start,
1221 br_off size,
1222 enum brl_flavour lock_flav)
1223{
1224 unsigned int i;
1225 struct lock_struct *locks = br_lck->lock_data;
1226 struct lock_context context;
1227
1228 context.smbpid = smbpid;
1229 context.pid = pid;
1230 context.tid = br_lck->fsp->conn->cnum;
1231
1232 for (i = 0; i < br_lck->num_locks; i++) {
1233 struct lock_struct *lock = &locks[i];
1234
1235 /* For pending locks we *always* care about the fnum. */
1236 if (brl_same_context(&lock->context, &context) &&
1237 lock->fnum == br_lck->fsp->fnum &&
1238 IS_PENDING_LOCK(lock->lock_type) &&
1239 lock->lock_flav == lock_flav &&
1240 lock->start == start &&
1241 lock->size == size) {
1242 break;
1243 }
1244 }
1245
1246 if (i == br_lck->num_locks) {
1247 /* Didn't find it. */
1248 return False;
1249 }
1250
1251 if (i < br_lck->num_locks - 1) {
1252 /* Found this particular pending lock - delete it */
1253 memmove(&locks[i], &locks[i+1],
1254 sizeof(*locks)*((br_lck->num_locks-1) - i));
1255 }
1256
1257 br_lck->num_locks -= 1;
1258 br_lck->modified = True;
1259 return True;
1260}
1261
1262/****************************************************************************
1263 Remove any locks associated with a open file.
1264 We return True if this process owns any other Windows locks on this
1265 fd and so we should not immediately close the fd.
1266****************************************************************************/
1267
1268void brl_close_fnum(struct messaging_context *msg_ctx,
1269 struct byte_range_lock *br_lck)
1270{
1271 files_struct *fsp = br_lck->fsp;
1272 uint16 tid = fsp->conn->cnum;
1273 int fnum = fsp->fnum;
1274 unsigned int i, j, dcount=0;
1275 int num_deleted_windows_locks = 0;
1276 struct lock_struct *locks = br_lck->lock_data;
1277 struct server_id pid = procid_self();
1278 bool unlock_individually = False;
1279
1280 if(lp_posix_locking(fsp->conn->params)) {
1281
1282 /* Check if there are any Windows locks associated with this dev/ino
1283 pair that are not this fnum. If so we need to call unlock on each
1284 one in order to release the system POSIX locks correctly. */
1285
1286 for (i=0; i < br_lck->num_locks; i++) {
1287 struct lock_struct *lock = &locks[i];
1288
1289 if (!procid_equal(&lock->context.pid, &pid)) {
1290 continue;
1291 }
1292
1293 if (lock->lock_type != READ_LOCK && lock->lock_type != WRITE_LOCK) {
1294 continue; /* Ignore pending. */
1295 }
1296
1297 if (lock->context.tid != tid || lock->fnum != fnum) {
1298 unlock_individually = True;
1299 break;
1300 }
1301 }
1302
1303 if (unlock_individually) {
1304 struct lock_struct *locks_copy;
1305 unsigned int num_locks_copy;
1306
1307 /* Copy the current lock array. */
1308 if (br_lck->num_locks) {
1309 locks_copy = (struct lock_struct *)TALLOC_MEMDUP(br_lck, locks, br_lck->num_locks * sizeof(struct lock_struct));
1310 if (!locks_copy) {
1311 smb_panic("brl_close_fnum: talloc failed");
1312 }
1313 } else {
1314 locks_copy = NULL;
1315 }
1316
1317 num_locks_copy = br_lck->num_locks;
1318
1319 for (i=0; i < num_locks_copy; i++) {
1320 struct lock_struct *lock = &locks_copy[i];
1321
1322 if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid) &&
1323 (lock->fnum == fnum)) {
1324 brl_unlock(msg_ctx,
1325 br_lck,
1326 lock->context.smbpid,
1327 pid,
1328 lock->start,
1329 lock->size,
1330 lock->lock_flav);
1331 }
1332 }
1333 return;
1334 }
1335 }
1336
1337 /* We can bulk delete - any POSIX locks will be removed when the fd closes. */
1338
1339 /* Remove any existing locks for this fnum (or any fnum if they're POSIX). */
1340
1341 for (i=0; i < br_lck->num_locks; i++) {
1342 struct lock_struct *lock = &locks[i];
1343 bool del_this_lock = False;
1344
1345 if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid)) {
1346 if ((lock->lock_flav == WINDOWS_LOCK) && (lock->fnum == fnum)) {
1347 del_this_lock = True;
1348 num_deleted_windows_locks++;
1349 } else if (lock->lock_flav == POSIX_LOCK) {
1350 del_this_lock = True;
1351 }
1352 }
1353
1354 if (del_this_lock) {
1355 /* Send unlock messages to any pending waiters that overlap. */
1356 for (j=0; j < br_lck->num_locks; j++) {
1357 struct lock_struct *pend_lock = &locks[j];
1358
1359 /* Ignore our own or non-pending locks. */
1360 if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
1361 continue;
1362 }
1363
1364 /* Optimisation - don't send to this fnum as we're
1365 closing it. */
1366 if (pend_lock->context.tid == tid &&
1367 procid_equal(&pend_lock->context.pid, &pid) &&
1368 pend_lock->fnum == fnum) {
1369 continue;
1370 }
1371
1372 /* We could send specific lock info here... */
1373 if (brl_pending_overlap(lock, pend_lock)) {
1374 messaging_send(msg_ctx, pend_lock->context.pid,
1375 MSG_SMB_UNLOCK, &data_blob_null);
1376 }
1377 }
1378
1379 /* found it - delete it */
1380 if (br_lck->num_locks > 1 && i < br_lck->num_locks - 1) {
1381 memmove(&locks[i], &locks[i+1],
1382 sizeof(*locks)*((br_lck->num_locks-1) - i));
1383 }
1384 br_lck->num_locks--;
1385 br_lck->modified = True;
1386 i--;
1387 dcount++;
1388 }
1389 }
1390
1391 if(lp_posix_locking(fsp->conn->params) && num_deleted_windows_locks) {
1392 /* Reduce the Windows lock POSIX reference count on this dev/ino pair. */
1393 reduce_windows_lock_ref_count(fsp, num_deleted_windows_locks);
1394 }
1395}
1396
1397/****************************************************************************
1398 Ensure this set of lock entries is valid.
1399****************************************************************************/
1400
1401static bool validate_lock_entries(unsigned int *pnum_entries, struct lock_struct **pplocks)
1402{
1403 unsigned int i;
1404 unsigned int num_valid_entries = 0;
1405 struct lock_struct *locks = *pplocks;
1406
1407 for (i = 0; i < *pnum_entries; i++) {
1408 struct lock_struct *lock_data = &locks[i];
1409 if (!process_exists(lock_data->context.pid)) {
1410 /* This process no longer exists - mark this
1411 entry as invalid by zeroing it. */
1412 ZERO_STRUCTP(lock_data);
1413 } else {
1414 num_valid_entries++;
1415 }
1416 }
1417
1418 if (num_valid_entries != *pnum_entries) {
1419 struct lock_struct *new_lock_data = NULL;
1420
1421 if (num_valid_entries) {
1422 new_lock_data = SMB_MALLOC_ARRAY(struct lock_struct, num_valid_entries);
1423 if (!new_lock_data) {
1424 DEBUG(3, ("malloc fail\n"));
1425 return False;
1426 }
1427
1428 num_valid_entries = 0;
1429 for (i = 0; i < *pnum_entries; i++) {
1430 struct lock_struct *lock_data = &locks[i];
1431 if (lock_data->context.smbpid &&
1432 lock_data->context.tid) {
1433 /* Valid (nonzero) entry - copy it. */
1434 memcpy(&new_lock_data[num_valid_entries],
1435 lock_data, sizeof(struct lock_struct));
1436 num_valid_entries++;
1437 }
1438 }
1439 }
1440
1441 SAFE_FREE(*pplocks);
1442 *pplocks = new_lock_data;
1443 *pnum_entries = num_valid_entries;
1444 }
1445
1446 return True;
1447}
1448
1449struct brl_forall_cb {
1450 void (*fn)(struct file_id id, struct server_id pid,
1451 enum brl_type lock_type,
1452 enum brl_flavour lock_flav,
1453 br_off start, br_off size,
1454 void *private_data);
1455 void *private_data;
1456};
1457
1458/****************************************************************************
1459 Traverse the whole database with this function, calling traverse_callback
1460 on each lock.
1461****************************************************************************/
1462
1463static int traverse_fn(struct db_record *rec, void *state)
1464{
1465 struct brl_forall_cb *cb = (struct brl_forall_cb *)state;
1466 struct lock_struct *locks;
1467 struct file_id *key;
1468 unsigned int i;
1469 unsigned int num_locks = 0;
1470 unsigned int orig_num_locks = 0;
1471
1472 /* In a traverse function we must make a copy of
1473 dbuf before modifying it. */
1474
1475 locks = (struct lock_struct *)memdup(rec->value.dptr,
1476 rec->value.dsize);
1477 if (!locks) {
1478 return -1; /* Terminate traversal. */
1479 }
1480
1481 key = (struct file_id *)rec->key.dptr;
1482 orig_num_locks = num_locks = rec->value.dsize/sizeof(*locks);
1483
1484 /* Ensure the lock db is clean of entries from invalid processes. */
1485
1486 if (!validate_lock_entries(&num_locks, &locks)) {
1487 SAFE_FREE(locks);
1488 return -1; /* Terminate traversal */
1489 }
1490
1491 if (orig_num_locks != num_locks) {
1492 if (num_locks) {
1493 TDB_DATA data;
1494 data.dptr = (uint8_t *)locks;
1495 data.dsize = num_locks*sizeof(struct lock_struct);
1496 rec->store(rec, data, TDB_REPLACE);
1497 } else {
1498 rec->delete_rec(rec);
1499 }
1500 }
1501
1502 if (cb->fn) {
1503 for ( i=0; i<num_locks; i++) {
1504 cb->fn(*key,
1505 locks[i].context.pid,
1506 locks[i].lock_type,
1507 locks[i].lock_flav,
1508 locks[i].start,
1509 locks[i].size,
1510 cb->private_data);
1511 }
1512 }
1513
1514 SAFE_FREE(locks);
1515 return 0;
1516}
1517
1518/*******************************************************************
1519 Call the specified function on each lock in the database.
1520********************************************************************/
1521
1522int brl_forall(void (*fn)(struct file_id id, struct server_id pid,
1523 enum brl_type lock_type,
1524 enum brl_flavour lock_flav,
1525 br_off start, br_off size,
1526 void *private_data),
1527 void *private_data)
1528{
1529 struct brl_forall_cb cb;
1530
1531 if (!brlock_db) {
1532 return 0;
1533 }
1534 cb.fn = fn;
1535 cb.private_data = private_data;
1536 return brlock_db->traverse(brlock_db, traverse_fn, &cb);
1537}
1538
1539/*******************************************************************
1540 Store a potentially modified set of byte range lock data back into
1541 the database.
1542 Unlock the record.
1543********************************************************************/
1544
1545static int byte_range_lock_destructor(struct byte_range_lock *br_lck)
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
1591static 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
1691struct 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
1697struct 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
1703struct 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
1713static 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
1735static 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
1754static 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
1803void 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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