2 Unix SMB/CIFS implementation.
4 Copyright (C) Jeremy Allison 1992-2006
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 POSIX locking support. Jeremy Allison (jeremy@valinux.com), Apr. 2000.
28 #define DBGC_CLASS DBGC_LOCKING
31 * The pending close database handle.
34 static TDB_CONTEXT *posix_pending_close_tdb;
36 /****************************************************************************
37 First - the functions that deal with the underlying system locks - these
38 functions are used no matter if we're mapping CIFS Windows locks or CIFS
39 POSIX locks onto POSIX.
40 ****************************************************************************/
42 /****************************************************************************
43 Utility function to map a lock type correctly depending on the open
45 ****************************************************************************/
47 static int map_posix_lock_type( files_struct *fsp, enum brl_type lock_type)
49 if((lock_type == WRITE_LOCK) && !fsp->can_write) {
51 * Many UNIX's cannot get a write lock on a file opened read-only.
52 * Win32 locking semantics allow this.
53 * Do the best we can and attempt a read-only lock.
55 DEBUG(10,("map_posix_lock_type: Downgrading write lock to read due to read-only file.\n"));
60 * This return should be the most normal, as we attempt
61 * to always open files read/write.
64 return (lock_type == READ_LOCK) ? F_RDLCK : F_WRLCK;
67 /****************************************************************************
69 ****************************************************************************/
71 static const char *posix_lock_type_name(int lock_type)
73 return (lock_type == F_RDLCK) ? "READ" : "WRITE";
76 /****************************************************************************
77 Check to see if the given unsigned lock range is within the possible POSIX
78 range. Modifies the given args to be in range if possible, just returns
80 ****************************************************************************/
82 static BOOL posix_lock_in_range(SMB_OFF_T *offset_out, SMB_OFF_T *count_out,
83 SMB_BIG_UINT u_offset, SMB_BIG_UINT u_count)
85 SMB_OFF_T offset = (SMB_OFF_T)u_offset;
86 SMB_OFF_T count = (SMB_OFF_T)u_count;
89 * For the type of system we are, attempt to
90 * find the maximum positive lock offset as an SMB_OFF_T.
93 #if defined(MAX_POSITIVE_LOCK_OFFSET) /* Some systems have arbitrary limits. */
95 SMB_OFF_T max_positive_lock_offset = (MAX_POSITIVE_LOCK_OFFSET);
97 #elif defined(LARGE_SMB_OFF_T) && !defined(HAVE_BROKEN_FCNTL64_LOCKS)
100 * In this case SMB_OFF_T is 64 bits,
101 * and the underlying system can handle 64 bit signed locks.
104 SMB_OFF_T mask2 = ((SMB_OFF_T)0x4) << (SMB_OFF_T_BITS-4);
105 SMB_OFF_T mask = (mask2<<1);
106 SMB_OFF_T max_positive_lock_offset = ~mask;
108 #else /* !LARGE_SMB_OFF_T || HAVE_BROKEN_FCNTL64_LOCKS */
111 * In this case either SMB_OFF_T is 32 bits,
112 * or the underlying system cannot handle 64 bit signed locks.
113 * All offsets & counts must be 2^31 or less.
116 SMB_OFF_T max_positive_lock_offset = 0x7FFFFFFF;
118 #endif /* !LARGE_SMB_OFF_T || HAVE_BROKEN_FCNTL64_LOCKS */
121 * POSIX locks of length zero mean lock to end-of-file.
122 * Win32 locks of length zero are point probes. Ignore
123 * any Win32 locks of length zero. JRA.
126 if (count == (SMB_OFF_T)0) {
127 DEBUG(10,("posix_lock_in_range: count = 0, ignoring.\n"));
132 * If the given offset was > max_positive_lock_offset then we cannot map this at all
136 if (u_offset & ~((SMB_BIG_UINT)max_positive_lock_offset)) {
137 DEBUG(10,("posix_lock_in_range: (offset = %.0f) offset > %.0f and we cannot handle this. Ignoring lock.\n",
138 (double)u_offset, (double)((SMB_BIG_UINT)max_positive_lock_offset) ));
143 * We must truncate the count to less than max_positive_lock_offset.
146 if (u_count & ~((SMB_BIG_UINT)max_positive_lock_offset)) {
147 count = max_positive_lock_offset;
151 * Truncate count to end at max lock offset.
154 if (offset + count < 0 || offset + count > max_positive_lock_offset) {
155 count = max_positive_lock_offset - offset;
159 * If we ate all the count, ignore this lock.
163 DEBUG(10,("posix_lock_in_range: Count = 0. Ignoring lock u_offset = %.0f, u_count = %.0f\n",
164 (double)u_offset, (double)u_count ));
169 * The mapping was successful.
172 DEBUG(10,("posix_lock_in_range: offset_out = %.0f, count_out = %.0f\n",
173 (double)offset, (double)count ));
175 *offset_out = offset;
181 /****************************************************************************
182 Actual function that does POSIX locks. Copes with 64 -> 32 bit cruft and
183 broken NFS implementations.
184 ****************************************************************************/
186 static BOOL posix_fcntl_lock(files_struct *fsp, int op, SMB_OFF_T offset, SMB_OFF_T count, int type)
190 DEBUG(8,("posix_fcntl_lock %d %d %.0f %.0f %d\n",fsp->fh->fd,op,(double)offset,(double)count,type));
192 ret = SMB_VFS_LOCK(fsp,fsp->fh->fd,op,offset,count,type);
194 if (!ret && ((errno == EFBIG) || (errno == ENOLCK) || (errno == EINVAL))) {
196 DEBUG(0,("posix_fcntl_lock: WARNING: lock request at offset %.0f, length %.0f returned\n",
197 (double)offset,(double)count));
198 DEBUG(0,("an %s error. This can happen when using 64 bit lock offsets\n", strerror(errno)));
199 DEBUG(0,("on 32 bit NFS mounted file systems.\n"));
202 * If the offset is > 0x7FFFFFFF then this will cause problems on
203 * 32 bit NFS mounted filesystems. Just ignore it.
206 if (offset & ~((SMB_OFF_T)0x7fffffff)) {
207 DEBUG(0,("Offset greater than 31 bits. Returning success.\n"));
211 if (count & ~((SMB_OFF_T)0x7fffffff)) {
212 /* 32 bit NFS file system, retry with smaller offset */
213 DEBUG(0,("Count greater than 31 bits - retrying with 31 bit truncated length.\n"));
216 ret = SMB_VFS_LOCK(fsp,fsp->fh->fd,op,offset,count,type);
220 DEBUG(8,("posix_fcntl_lock: Lock call %s\n", ret ? "successful" : "failed"));
224 /****************************************************************************
225 Actual function that gets POSIX locks. Copes with 64 -> 32 bit cruft and
226 broken NFS implementations.
227 ****************************************************************************/
229 static BOOL posix_fcntl_getlock(files_struct *fsp, SMB_OFF_T *poffset, SMB_OFF_T *pcount, int *ptype)
234 DEBUG(8,("posix_fcntl_getlock %d %.0f %.0f %d\n",
235 fsp->fh->fd,(double)*poffset,(double)*pcount,*ptype));
237 ret = SMB_VFS_GETLOCK(fsp,fsp->fh->fd,poffset,pcount,ptype,&pid);
239 if (!ret && ((errno == EFBIG) || (errno == ENOLCK) || (errno == EINVAL))) {
241 DEBUG(0,("posix_fcntl_getlock: WARNING: lock request at offset %.0f, length %.0f returned\n",
242 (double)*poffset,(double)*pcount));
243 DEBUG(0,("an %s error. This can happen when using 64 bit lock offsets\n", strerror(errno)));
244 DEBUG(0,("on 32 bit NFS mounted file systems.\n"));
247 * If the offset is > 0x7FFFFFFF then this will cause problems on
248 * 32 bit NFS mounted filesystems. Just ignore it.
251 if (*poffset & ~((SMB_OFF_T)0x7fffffff)) {
252 DEBUG(0,("Offset greater than 31 bits. Returning success.\n"));
256 if (*pcount & ~((SMB_OFF_T)0x7fffffff)) {
257 /* 32 bit NFS file system, retry with smaller offset */
258 DEBUG(0,("Count greater than 31 bits - retrying with 31 bit truncated length.\n"));
260 *pcount &= 0x7fffffff;
261 ret = SMB_VFS_GETLOCK(fsp,fsp->fh->fd,poffset,pcount,ptype,&pid);
265 DEBUG(8,("posix_fcntl_getlock: Lock query call %s\n", ret ? "successful" : "failed"));
269 /****************************************************************************
270 POSIX function to see if a file region is locked. Returns True if the
271 region is locked, False otherwise.
272 ****************************************************************************/
274 BOOL is_posix_locked(files_struct *fsp,
275 SMB_BIG_UINT *pu_offset,
276 SMB_BIG_UINT *pu_count,
277 enum brl_type *plock_type,
278 enum brl_flavour lock_flav)
282 int posix_lock_type = map_posix_lock_type(fsp,*plock_type);
284 DEBUG(10,("is_posix_locked: File %s, offset = %.0f, count = %.0f, type = %s\n",
285 fsp->fsp_name, (double)*pu_offset, (double)*pu_count, posix_lock_type_name(*plock_type) ));
288 * If the requested lock won't fit in the POSIX range, we will
289 * never set it, so presume it is not locked.
292 if(!posix_lock_in_range(&offset, &count, *pu_offset, *pu_count)) {
296 if (!posix_fcntl_getlock(fsp,&offset,&count,&posix_lock_type)) {
300 if (posix_lock_type == F_UNLCK) {
304 if (lock_flav == POSIX_LOCK) {
305 /* Only POSIX lock queries need to know the details. */
306 *pu_offset = (SMB_BIG_UINT)offset;
307 *pu_count = (SMB_BIG_UINT)count;
308 *plock_type = (posix_lock_type == F_RDLCK) ? READ_LOCK : WRITE_LOCK;
313 /****************************************************************************
314 Next - the functions that deal with in memory database storing representations
315 of either Windows CIFS locks or POSIX CIFS locks.
316 ****************************************************************************/
318 /* The key used in the in-memory POSIX databases. */
320 struct lock_ref_count_key {
331 /*******************************************************************
332 Form a static locking key for a dev/inode pair for the fd array.
333 ******************************************************************/
335 static TDB_DATA fd_array_key(SMB_DEV_T dev, SMB_INO_T inode)
337 static struct fd_key key;
340 memset(&key, '\0', sizeof(key));
343 kbuf.dptr = (uint8 *)&key;
344 kbuf.dsize = sizeof(key);
348 /*******************************************************************
349 Form a static locking key for a dev/inode pair for the lock ref count
350 ******************************************************************/
352 static TDB_DATA locking_ref_count_key(SMB_DEV_T dev, SMB_INO_T inode)
354 static struct lock_ref_count_key key;
357 memset(&key, '\0', sizeof(key));
361 kbuf.dptr = (uint8 *)&key;
362 kbuf.dsize = sizeof(key);
366 /*******************************************************************
367 Convenience function to get an fd_array key from an fsp.
368 ******************************************************************/
370 static TDB_DATA fd_array_key_fsp(files_struct *fsp)
372 return fd_array_key(fsp->dev, fsp->inode);
375 /*******************************************************************
376 Convenience function to get a lock ref count key from an fsp.
377 ******************************************************************/
379 static TDB_DATA locking_ref_count_key_fsp(files_struct *fsp)
381 return locking_ref_count_key(fsp->dev, fsp->inode);
384 /*******************************************************************
385 Create the in-memory POSIX lock databases.
386 ********************************************************************/
388 BOOL posix_locking_init(int read_only)
390 if (posix_pending_close_tdb) {
394 if (!posix_pending_close_tdb) {
395 posix_pending_close_tdb = tdb_open_log(NULL, 0, TDB_INTERNAL,
396 read_only?O_RDONLY:(O_RDWR|O_CREAT), 0644);
398 if (!posix_pending_close_tdb) {
399 DEBUG(0,("Failed to open POSIX pending close database.\n"));
406 /*******************************************************************
407 Delete the in-memory POSIX lock databases.
408 ********************************************************************/
410 BOOL posix_locking_end(void)
412 if (posix_pending_close_tdb && tdb_close(posix_pending_close_tdb) != 0) {
418 /****************************************************************************
419 Next - the functions that deal with storing fd's that have outstanding
420 POSIX locks when closed.
421 ****************************************************************************/
423 /****************************************************************************
424 The records in posix_pending_close_tdb are composed of an array of ints
425 keyed by dev/ino pair.
426 The first int is a reference count of the number of outstanding locks on
427 all open fd's on this dev/ino pair. Any subsequent ints are the fd's that
428 were open on this dev/ino pair that should have been closed, but can't as
429 the lock ref count is non zero.
430 ****************************************************************************/
432 /****************************************************************************
433 Keep a reference count of the number of Windows locks open on this dev/ino
434 pair. Creates entry if it doesn't exist.
435 ****************************************************************************/
437 static void increment_windows_lock_ref_count(files_struct *fsp)
439 TDB_DATA kbuf = locking_ref_count_key_fsp(fsp);
443 dbuf = tdb_fetch(posix_pending_close_tdb, kbuf);
444 if (dbuf.dptr == NULL) {
445 dbuf.dptr = (uint8 *)SMB_MALLOC_P(int);
447 smb_panic("increment_windows_lock_ref_count: malloc fail.\n");
449 memset(dbuf.dptr, '\0', sizeof(int));
450 dbuf.dsize = sizeof(int);
453 memcpy(&lock_ref_count, dbuf.dptr, sizeof(int));
455 memcpy(dbuf.dptr, &lock_ref_count, sizeof(int));
457 if (tdb_store(posix_pending_close_tdb, kbuf, dbuf, TDB_REPLACE) == -1) {
458 smb_panic("increment_windows_lock_ref_count: tdb_store_fail.\n");
460 SAFE_FREE(dbuf.dptr);
462 DEBUG(10,("increment_windows_lock_ref_count for file now %s = %d\n",
463 fsp->fsp_name, lock_ref_count ));
466 static void decrement_windows_lock_ref_count(files_struct *fsp)
468 TDB_DATA kbuf = locking_ref_count_key_fsp(fsp);
472 dbuf = tdb_fetch(posix_pending_close_tdb, kbuf);
474 smb_panic("decrement_windows_lock_ref_count: logic error.\n");
477 memcpy(&lock_ref_count, dbuf.dptr, sizeof(int));
479 memcpy(dbuf.dptr, &lock_ref_count, sizeof(int));
481 if (lock_ref_count < 0) {
482 smb_panic("decrement_windows_lock_ref_count: lock_count logic error.\n");
485 if (tdb_store(posix_pending_close_tdb, kbuf, dbuf, TDB_REPLACE) == -1) {
486 smb_panic("decrement_windows_lock_ref_count: tdb_store_fail.\n");
488 SAFE_FREE(dbuf.dptr);
490 DEBUG(10,("decrement_windows_lock_ref_count for file now %s = %d\n",
491 fsp->fsp_name, lock_ref_count ));
494 /****************************************************************************
495 Bulk delete - subtract as many locks as we've just deleted.
496 ****************************************************************************/
498 void reduce_windows_lock_ref_count(files_struct *fsp, unsigned int dcount)
500 TDB_DATA kbuf = locking_ref_count_key_fsp(fsp);
504 dbuf = tdb_fetch(posix_pending_close_tdb, kbuf);
509 memcpy(&lock_ref_count, dbuf.dptr, sizeof(int));
510 lock_ref_count -= dcount;
512 if (lock_ref_count < 0) {
513 smb_panic("reduce_windows_lock_ref_count: lock_count logic error.\n");
515 memcpy(dbuf.dptr, &lock_ref_count, sizeof(int));
517 if (tdb_store(posix_pending_close_tdb, kbuf, dbuf, TDB_REPLACE) == -1) {
518 smb_panic("reduce_windows_lock_ref_count: tdb_store_fail.\n");
520 SAFE_FREE(dbuf.dptr);
522 DEBUG(10,("reduce_windows_lock_ref_count for file now %s = %d\n",
523 fsp->fsp_name, lock_ref_count ));
526 /****************************************************************************
527 Fetch the lock ref count.
528 ****************************************************************************/
530 static int get_windows_lock_ref_count(files_struct *fsp)
532 TDB_DATA kbuf = locking_ref_count_key_fsp(fsp);
536 dbuf = tdb_fetch(posix_pending_close_tdb, kbuf);
540 memcpy(&lock_ref_count, dbuf.dptr, sizeof(int));
542 SAFE_FREE(dbuf.dptr);
544 DEBUG(10,("get_windows_lock_count for file %s = %d\n",
545 fsp->fsp_name, lock_ref_count ));
546 return lock_ref_count;
549 /****************************************************************************
550 Delete a lock_ref_count entry.
551 ****************************************************************************/
553 static void delete_windows_lock_ref_count(files_struct *fsp)
555 TDB_DATA kbuf = locking_ref_count_key_fsp(fsp);
557 /* Not a bug if it doesn't exist - no locks were ever granted. */
558 tdb_delete(posix_pending_close_tdb, kbuf);
559 DEBUG(10,("delete_windows_lock_ref_count for file %s\n", fsp->fsp_name));
562 /****************************************************************************
563 Add an fd to the pending close tdb.
564 ****************************************************************************/
566 static void add_fd_to_close_entry(files_struct *fsp)
568 TDB_DATA kbuf = fd_array_key_fsp(fsp);
574 dbuf = tdb_fetch(posix_pending_close_tdb, kbuf);
576 dbuf.dptr = (uint8 *)SMB_REALLOC(dbuf.dptr, dbuf.dsize + sizeof(int));
578 smb_panic("add_fd_to_close_entry: Realloc fail !\n");
581 memcpy(dbuf.dptr + dbuf.dsize, &fsp->fh->fd, sizeof(int));
582 dbuf.dsize += sizeof(int);
584 if (tdb_store(posix_pending_close_tdb, kbuf, dbuf, TDB_REPLACE) == -1) {
585 smb_panic("add_fd_to_close_entry: tdb_store_fail.\n");
588 DEBUG(10,("add_fd_to_close_entry: added fd %d file %s\n",
589 fsp->fh->fd, fsp->fsp_name ));
591 SAFE_FREE(dbuf.dptr);
594 /****************************************************************************
595 Remove all fd entries for a specific dev/inode pair from the tdb.
596 ****************************************************************************/
598 static void delete_close_entries(files_struct *fsp)
600 TDB_DATA kbuf = fd_array_key_fsp(fsp);
602 if (tdb_delete(posix_pending_close_tdb, kbuf) == -1) {
603 smb_panic("delete_close_entries: tdb_delete fail !\n");
607 /****************************************************************************
608 Get the array of POSIX pending close records for an open fsp. Caller must
609 free. Returns number of entries.
610 ****************************************************************************/
612 static size_t get_posix_pending_close_entries(files_struct *fsp, int **entries)
614 TDB_DATA kbuf = fd_array_key_fsp(fsp);
621 dbuf = tdb_fetch(posix_pending_close_tdb, kbuf);
627 *entries = (int *)dbuf.dptr;
628 count = (size_t)(dbuf.dsize / sizeof(int));
633 /****************************************************************************
634 Deal with pending closes needed by POSIX locking support.
635 Note that posix_locking_close_file() is expected to have been called
636 to delete all locks on this fsp before this function is called.
637 ****************************************************************************/
639 NTSTATUS fd_close_posix(struct connection_struct *conn, files_struct *fsp)
643 int *fd_array = NULL;
646 if (!lp_locking(fsp->conn->params) || !lp_posix_locking(conn->params)) {
648 * No locking or POSIX to worry about or we want POSIX semantics
649 * which will lose all locks on all fd's open on this dev/inode,
652 ret = SMB_VFS_CLOSE(fsp,fsp->fh->fd);
654 return map_nt_error_from_unix(errno);
657 if (get_windows_lock_ref_count(fsp)) {
660 * There are outstanding locks on this dev/inode pair on other fds.
661 * Add our fd to the pending close tdb and set fsp->fh->fd to -1.
664 add_fd_to_close_entry(fsp);
670 * No outstanding locks. Get the pending close fd's
671 * from the tdb and close them all.
674 count = get_posix_pending_close_entries(fsp, &fd_array);
677 DEBUG(10,("fd_close_posix: doing close on %u fd's.\n", (unsigned int)count ));
679 for(i = 0; i < count; i++) {
680 if (SMB_VFS_CLOSE(fsp,fd_array[i]) == -1) {
686 * Delete all fd's stored in the tdb
687 * for this dev/inode pair.
690 delete_close_entries(fsp);
695 /* Don't need a lock ref count on this dev/ino anymore. */
696 delete_windows_lock_ref_count(fsp);
699 * Finally close the fd associated with this fsp.
702 ret = SMB_VFS_CLOSE(fsp,fsp->fh->fd);
704 if (ret == 0 && saved_errno != 0) {
712 return map_nt_error_from_unix(errno);
718 /****************************************************************************
719 Next - the functions that deal with the mapping CIFS Windows locks onto
720 the underlying system POSIX locks.
721 ****************************************************************************/
724 * Structure used when splitting a lock range
725 * into a POSIX lock range. Doubly linked list.
729 struct lock_list *next;
730 struct lock_list *prev;
735 /****************************************************************************
736 Create a list of lock ranges that don't overlap a given range. Used in calculating
737 POSIX locks and unlocks. This is a difficult function that requires ASCII art to
739 ****************************************************************************/
741 static struct lock_list *posix_lock_list(TALLOC_CTX *ctx,
742 struct lock_list *lhead,
743 const struct lock_context *lock_ctx, /* Lock context lhead belongs to. */
745 const struct lock_struct *plocks,
751 * Check the current lock list on this dev/inode pair.
752 * Quit if the list is deleted.
755 DEBUG(10,("posix_lock_list: curr: start=%.0f,size=%.0f\n",
756 (double)lhead->start, (double)lhead->size ));
758 for (i=0; i<num_locks && lhead; i++) {
759 const struct lock_struct *lock = &plocks[i];
760 struct lock_list *l_curr;
762 /* Ignore all but read/write locks. */
763 if (lock->lock_type != READ_LOCK && lock->lock_type != WRITE_LOCK) {
767 /* Ignore locks not owned by this process. */
768 if (!procid_equal(&lock->context.pid, &lock_ctx->pid)) {
773 * Walk the lock list, checking for overlaps. Note that
774 * the lock list can expand within this loop if the current
775 * range being examined needs to be split.
778 for (l_curr = lhead; l_curr;) {
780 DEBUG(10,("posix_lock_list: lock: fnum=%d: start=%.0f,size=%.0f:type=%s", lock->fnum,
781 (double)lock->start, (double)lock->size, posix_lock_type_name(lock->lock_type) ));
783 if ( (l_curr->start >= (lock->start + lock->size)) ||
784 (lock->start >= (l_curr->start + l_curr->size))) {
786 /* No overlap with existing lock - leave this range alone. */
787 /*********************************************
798 **********************************************/
800 DEBUG(10,(" no overlap case.\n" ));
802 l_curr = l_curr->next;
804 } else if ( (l_curr->start >= lock->start) &&
805 (l_curr->start + l_curr->size <= lock->start + lock->size) ) {
808 * This range is completely overlapped by this existing lock range
809 * and thus should have no effect. Delete it from the list.
811 /*********************************************
815 +---------------------------+
817 +---------------------------+
818 **********************************************/
819 /* Save the next pointer */
820 struct lock_list *ul_next = l_curr->next;
822 DEBUG(10,(" delete case.\n" ));
824 DLIST_REMOVE(lhead, l_curr);
826 break; /* No more list... */
831 } else if ( (l_curr->start >= lock->start) &&
832 (l_curr->start < lock->start + lock->size) &&
833 (l_curr->start + l_curr->size > lock->start + lock->size) ) {
836 * This range overlaps the existing lock range at the high end.
837 * Truncate by moving start to existing range end and reducing size.
839 /*********************************************
850 **********************************************/
852 l_curr->size = (l_curr->start + l_curr->size) - (lock->start + lock->size);
853 l_curr->start = lock->start + lock->size;
855 DEBUG(10,(" truncate high case: start=%.0f,size=%.0f\n",
856 (double)l_curr->start, (double)l_curr->size ));
858 l_curr = l_curr->next;
860 } else if ( (l_curr->start < lock->start) &&
861 (l_curr->start + l_curr->size > lock->start) &&
862 (l_curr->start + l_curr->size <= lock->start + lock->size) ) {
865 * This range overlaps the existing lock range at the low end.
866 * Truncate by reducing size.
868 /*********************************************
879 **********************************************/
881 l_curr->size = lock->start - l_curr->start;
883 DEBUG(10,(" truncate low case: start=%.0f,size=%.0f\n",
884 (double)l_curr->start, (double)l_curr->size ));
886 l_curr = l_curr->next;
888 } else if ( (l_curr->start < lock->start) &&
889 (l_curr->start + l_curr->size > lock->start + lock->size) ) {
891 * Worst case scenario. Range completely overlaps an existing
892 * lock range. Split the request into two, push the new (upper) request
893 * into the dlink list, and continue with the entry after l_new (as we
894 * know that l_new will not overlap with this lock).
896 /*********************************************
897 +---------------------------+
899 +---------------------------+
904 +-------+ +---------+
906 +-------+ +---------+
907 **********************************************/
908 struct lock_list *l_new = TALLOC_P(ctx, struct lock_list);
911 DEBUG(0,("posix_lock_list: talloc fail.\n"));
912 return NULL; /* The talloc_destroy takes care of cleanup. */
916 l_new->start = lock->start + lock->size;
917 l_new->size = l_curr->start + l_curr->size - l_new->start;
919 /* Truncate the l_curr. */
920 l_curr->size = lock->start - l_curr->start;
922 DEBUG(10,(" split case: curr: start=%.0f,size=%.0f \
923 new: start=%.0f,size=%.0f\n", (double)l_curr->start, (double)l_curr->size,
924 (double)l_new->start, (double)l_new->size ));
927 * Add into the dlink list after the l_curr point - NOT at lhead.
928 * Note we can't use DLINK_ADD here as this inserts at the head of the given list.
931 l_new->prev = l_curr;
932 l_new->next = l_curr->next;
933 l_curr->next = l_new;
935 /* And move after the link we added. */
936 l_curr = l_new->next;
941 * This logic case should never happen. Ensure this is the
942 * case by forcing an abort.... Remove in production.
946 slprintf(msg, sizeof(msg)-1, "logic flaw in cases: l_curr: start = %.0f, size = %.0f : \
947 lock: start = %.0f, size = %.0f\n", (double)l_curr->start, (double)l_curr->size, (double)lock->start, (double)lock->size );
951 } /* end for ( l_curr = lhead; l_curr;) */
952 } /* end for (i=0; i<num_locks && ul_head; i++) */
957 /****************************************************************************
958 POSIX function to acquire a lock. Returns True if the
959 lock could be granted, False if not.
960 ****************************************************************************/
962 BOOL set_posix_lock_windows_flavour(files_struct *fsp,
963 SMB_BIG_UINT u_offset,
964 SMB_BIG_UINT u_count,
965 enum brl_type lock_type,
966 const struct lock_context *lock_ctx,
967 const struct lock_struct *plocks,
973 int posix_lock_type = map_posix_lock_type(fsp,lock_type);
976 TALLOC_CTX *l_ctx = NULL;
977 struct lock_list *llist = NULL;
978 struct lock_list *ll = NULL;
980 DEBUG(5,("set_posix_lock_windows_flavour: File %s, offset = %.0f, count = %.0f, type = %s\n",
981 fsp->fsp_name, (double)u_offset, (double)u_count, posix_lock_type_name(lock_type) ));
984 * If the requested lock won't fit in the POSIX range, we will
985 * pretend it was successful.
988 if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) {
989 increment_windows_lock_ref_count(fsp);
994 * Windows is very strange. It allows read locks to be overlayed
995 * (even over a write lock), but leaves the write lock in force until the first
996 * unlock. It also reference counts the locks. This means the following sequence :
999 * ------------------------------------------------------------------------
1000 * WRITE LOCK : start = 2, len = 10
1001 * READ LOCK: start =0, len = 10 - FAIL
1002 * READ LOCK : start = 0, len = 14
1003 * READ LOCK: start =0, len = 10 - FAIL
1004 * UNLOCK : start = 2, len = 10
1005 * READ LOCK: start =0, len = 10 - OK
1007 * Under POSIX, the same sequence in steps 1 and 2 would not be reference counted, but
1008 * would leave a single read lock over the 0-14 region.
1011 if ((l_ctx = talloc_init("set_posix_lock")) == NULL) {
1012 DEBUG(0,("set_posix_lock_windows_flavour: unable to init talloc context.\n"));
1016 if ((ll = TALLOC_P(l_ctx, struct lock_list)) == NULL) {
1017 DEBUG(0,("set_posix_lock_windows_flavour: unable to talloc unlock list.\n"));
1018 talloc_destroy(l_ctx);
1023 * Create the initial list entry containing the
1024 * lock we want to add.
1031 DLIST_ADD(llist, ll);
1034 * The following call calculates if there are any
1035 * overlapping locks held by this process on
1036 * fd's open on the same file and splits this list
1037 * into a list of lock ranges that do not overlap with existing
1041 llist = posix_lock_list(l_ctx,
1043 lock_ctx, /* Lock context llist belongs to. */
1049 * Add the POSIX locks on the list of ranges returned.
1050 * As the lock is supposed to be added atomically, we need to
1051 * back out all the locks if any one of these calls fail.
1054 for (lock_count = 0, ll = llist; ll; ll = ll->next, lock_count++) {
1058 DEBUG(5,("set_posix_lock_windows_flavour: Real lock: Type = %s: offset = %.0f, count = %.0f\n",
1059 posix_lock_type_name(posix_lock_type), (double)offset, (double)count ));
1061 if (!posix_fcntl_lock(fsp,SMB_F_SETLK,offset,count,posix_lock_type)) {
1063 DEBUG(5,("set_posix_lock_windows_flavour: Lock fail !: Type = %s: offset = %.0f, count = %.0f. Errno = %s\n",
1064 posix_lock_type_name(posix_lock_type), (double)offset, (double)count, strerror(errno) ));
1073 * Back out all the POSIX locks we have on fail.
1076 for (ll = llist; lock_count; ll = ll->next, lock_count--) {
1080 DEBUG(5,("set_posix_lock_windows_flavour: Backing out locks: Type = %s: offset = %.0f, count = %.0f\n",
1081 posix_lock_type_name(posix_lock_type), (double)offset, (double)count ));
1083 posix_fcntl_lock(fsp,SMB_F_SETLK,offset,count,F_UNLCK);
1086 /* Remember the number of Windows locks we have on this dev/ino pair. */
1087 increment_windows_lock_ref_count(fsp);
1090 talloc_destroy(l_ctx);
1094 /****************************************************************************
1095 POSIX function to release a lock. Returns True if the
1096 lock could be released, False if not.
1097 ****************************************************************************/
1099 BOOL release_posix_lock_windows_flavour(files_struct *fsp,
1100 SMB_BIG_UINT u_offset,
1101 SMB_BIG_UINT u_count,
1102 enum brl_type deleted_lock_type,
1103 const struct lock_context *lock_ctx,
1104 const struct lock_struct *plocks,
1110 TALLOC_CTX *ul_ctx = NULL;
1111 struct lock_list *ulist = NULL;
1112 struct lock_list *ul = NULL;
1114 DEBUG(5,("release_posix_lock_windows_flavour: File %s, offset = %.0f, count = %.0f\n",
1115 fsp->fsp_name, (double)u_offset, (double)u_count ));
1117 /* Remember the number of Windows locks we have on this dev/ino pair. */
1118 decrement_windows_lock_ref_count(fsp);
1121 * If the requested lock won't fit in the POSIX range, we will
1122 * pretend it was successful.
1125 if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) {
1129 if ((ul_ctx = talloc_init("release_posix_lock")) == NULL) {
1130 DEBUG(0,("release_posix_lock_windows_flavour: unable to init talloc context.\n"));
1134 if ((ul = TALLOC_P(ul_ctx, struct lock_list)) == NULL) {
1135 DEBUG(0,("release_posix_lock_windows_flavour: unable to talloc unlock list.\n"));
1136 talloc_destroy(ul_ctx);
1141 * Create the initial list entry containing the
1142 * lock we want to remove.
1149 DLIST_ADD(ulist, ul);
1152 * The following call calculates if there are any
1153 * overlapping locks held by this process on
1154 * fd's open on the same file and creates a
1155 * list of unlock ranges that will allow
1156 * POSIX lock ranges to remain on the file whilst the
1157 * unlocks are performed.
1160 ulist = posix_lock_list(ul_ctx,
1162 lock_ctx, /* Lock context ulist belongs to. */
1168 * If there were any overlapped entries (list is > 1 or size or start have changed),
1169 * and the lock_type we just deleted from
1170 * the upper layer tdb was a write lock, then before doing the unlock we need to downgrade
1171 * the POSIX lock to a read lock. This allows any overlapping read locks
1172 * to be atomically maintained.
1175 if (deleted_lock_type == WRITE_LOCK &&
1176 (!ulist || ulist->next != NULL || ulist->start != offset || ulist->size != count)) {
1178 DEBUG(5,("release_posix_lock_windows_flavour: downgrading lock to READ: offset = %.0f, count = %.0f\n",
1179 (double)offset, (double)count ));
1181 if (!posix_fcntl_lock(fsp,SMB_F_SETLK,offset,count,F_RDLCK)) {
1182 DEBUG(0,("release_posix_lock_windows_flavour: downgrade of lock failed with error %s !\n", strerror(errno) ));
1183 talloc_destroy(ul_ctx);
1189 * Release the POSIX locks on the list of ranges returned.
1192 for(; ulist; ulist = ulist->next) {
1193 offset = ulist->start;
1194 count = ulist->size;
1196 DEBUG(5,("release_posix_lock_windows_flavour: Real unlock: offset = %.0f, count = %.0f\n",
1197 (double)offset, (double)count ));
1199 if (!posix_fcntl_lock(fsp,SMB_F_SETLK,offset,count,F_UNLCK)) {
1204 talloc_destroy(ul_ctx);
1208 /****************************************************************************
1209 Next - the functions that deal with mapping CIFS POSIX locks onto
1210 the underlying system POSIX locks.
1211 ****************************************************************************/
1213 /****************************************************************************
1214 POSIX function to acquire a lock. Returns True if the
1215 lock could be granted, False if not.
1216 As POSIX locks don't stack or conflict (they just overwrite)
1217 we can map the requested lock directly onto a system one. We
1218 know it doesn't conflict with locks on other contexts as the
1219 upper layer would have refused it.
1220 ****************************************************************************/
1222 BOOL set_posix_lock_posix_flavour(files_struct *fsp,
1223 SMB_BIG_UINT u_offset,
1224 SMB_BIG_UINT u_count,
1225 enum brl_type lock_type,
1230 int posix_lock_type = map_posix_lock_type(fsp,lock_type);
1232 DEBUG(5,("set_posix_lock_posix_flavour: File %s, offset = %.0f, count = %.0f, type = %s\n",
1233 fsp->fsp_name, (double)u_offset, (double)u_count, posix_lock_type_name(lock_type) ));
1236 * If the requested lock won't fit in the POSIX range, we will
1237 * pretend it was successful.
1240 if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) {
1244 if (!posix_fcntl_lock(fsp,SMB_F_SETLK,offset,count,posix_lock_type)) {
1246 DEBUG(5,("set_posix_lock_posix_flavour: Lock fail !: Type = %s: offset = %.0f, count = %.0f. Errno = %s\n",
1247 posix_lock_type_name(posix_lock_type), (double)offset, (double)count, strerror(errno) ));
1253 /****************************************************************************
1254 POSIX function to release a lock. Returns True if the
1255 lock could be released, False if not.
1256 We are given a complete lock state from the upper layer which is what the lock
1257 state should be after the unlock has already been done, so what
1258 we do is punch out holes in the unlock range where locks owned by this process
1259 have a different lock context.
1260 ****************************************************************************/
1262 BOOL release_posix_lock_posix_flavour(files_struct *fsp,
1263 SMB_BIG_UINT u_offset,
1264 SMB_BIG_UINT u_count,
1265 const struct lock_context *lock_ctx,
1266 const struct lock_struct *plocks,
1272 TALLOC_CTX *ul_ctx = NULL;
1273 struct lock_list *ulist = NULL;
1274 struct lock_list *ul = NULL;
1276 DEBUG(5,("release_posix_lock_posix_flavour: File %s, offset = %.0f, count = %.0f\n",
1277 fsp->fsp_name, (double)u_offset, (double)u_count ));
1280 * If the requested lock won't fit in the POSIX range, we will
1281 * pretend it was successful.
1284 if(!posix_lock_in_range(&offset, &count, u_offset, u_count)) {
1288 if ((ul_ctx = talloc_init("release_posix_lock")) == NULL) {
1289 DEBUG(0,("release_posix_lock_windows_flavour: unable to init talloc context.\n"));
1293 if ((ul = TALLOC_P(ul_ctx, struct lock_list)) == NULL) {
1294 DEBUG(0,("release_posix_lock_windows_flavour: unable to talloc unlock list.\n"));
1295 talloc_destroy(ul_ctx);
1300 * Create the initial list entry containing the
1301 * lock we want to remove.
1308 DLIST_ADD(ulist, ul);
1311 * Walk the given array creating a linked list
1312 * of unlock requests.
1315 ulist = posix_lock_list(ul_ctx,
1317 lock_ctx, /* Lock context ulist belongs to. */
1323 * Release the POSIX locks on the list of ranges returned.
1326 for(; ulist; ulist = ulist->next) {
1327 offset = ulist->start;
1328 count = ulist->size;
1330 DEBUG(5,("release_posix_lock_posix_flavour: Real unlock: offset = %.0f, count = %.0f\n",
1331 (double)offset, (double)count ));
1333 if (!posix_fcntl_lock(fsp,SMB_F_SETLK,offset,count,F_UNLCK)) {
1338 talloc_destroy(ul_ctx);