2 Unix SMB/CIFS implementation.
4 Copyright (C) Andrew Tridgell 1992-2000
5 Copyright (C) Jeremy Allison 1992-2000
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 12 aug 96: Erik.Devriendt@te6.siemens.be
24 added support for shared memory implementation of share mode locking
26 May 1997. Jeremy Allison (jallison@whistle.com). Modified share mode
27 locking to deal with multiple share modes per open file.
29 September 1997. Jeremy Allison (jallison@whistle.com). Added oplock
32 rewrtten completely to use new tdb code. Tridge, Dec '99
34 Added POSIX locking support. Jeremy Allison (jeremy@valinux.com), Apr. 2000.
40 /* the locking database handle */
41 static TDB_CONTEXT *tdb;
43 /****************************************************************************
45 ****************************************************************************/
47 static const char *lock_type_name(enum brl_type lock_type)
49 return (lock_type == READ_LOCK) ? "READ" : "WRITE";
52 /****************************************************************************
53 Utility function called to see if a file region is locked.
54 If check_self is True, then checks on our own fd with the same locking context
55 are still made. If check_self is False, then checks are not made on our own fd
56 with the same locking context are not made.
57 ****************************************************************************/
59 BOOL is_locked(files_struct *fsp,connection_struct *conn,
60 SMB_BIG_UINT count,SMB_BIG_UINT offset,
61 enum brl_type lock_type, BOOL check_self)
63 int snum = SNUM(conn);
69 if (!lp_locking(snum) || !lp_strict_locking(snum))
72 ret = !brl_locktest(fsp->dev, fsp->inode, fsp->fnum,
73 global_smbpid, sys_getpid(), conn->cnum,
74 offset, count, lock_type, check_self);
76 DEBUG(10,("is_locked: brl start=%.0f len=%.0f %s for file %s\n",
77 (double)offset, (double)count, ret ? "locked" : "unlocked",
81 * There is no lock held by an SMB daemon, check to
82 * see if there is a POSIX lock from a UNIX or NFS process.
85 if(!ret && lp_posix_locking(snum)) {
86 ret = is_posix_locked(fsp, offset, count, lock_type);
88 DEBUG(10,("is_locked: posix start=%.0f len=%.0f %s for file %s\n",
89 (double)offset, (double)count, ret ? "locked" : "unlocked",
96 /****************************************************************************
97 Utility function called by locking requests.
98 ****************************************************************************/
100 NTSTATUS do_lock(files_struct *fsp,connection_struct *conn, uint16 lock_pid,
101 SMB_BIG_UINT count,SMB_BIG_UINT offset,enum brl_type lock_type)
105 if (!lp_locking(SNUM(conn)))
108 /* NOTE! 0 byte long ranges ARE allowed and should be stored */
111 DEBUG(10,("do_lock: lock type %s start=%.0f len=%.0f requested for file %s\n",
112 lock_type_name(lock_type), (double)offset, (double)count, fsp->fsp_name ));
114 if (OPEN_FSP(fsp) && fsp->can_lock && (fsp->conn == conn)) {
115 status = brl_lock(fsp->dev, fsp->inode, fsp->fnum,
116 lock_pid, sys_getpid(), conn->cnum,
120 if (NT_STATUS_IS_OK(status) && lp_posix_locking(SNUM(conn))) {
123 * Try and get a POSIX lock on this range.
124 * Note that this is ok if it is a read lock
125 * overlapping on a different fd. JRA.
128 if (!set_posix_lock(fsp, offset, count, lock_type)) {
129 status = NT_STATUS_LOCK_NOT_GRANTED;
131 * We failed to map - we must now remove the brl
134 (void)brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
135 lock_pid, sys_getpid(), conn->cnum,
144 /****************************************************************************
145 Utility function called by unlocking requests.
146 ****************************************************************************/
148 NTSTATUS do_unlock(files_struct *fsp,connection_struct *conn, uint16 lock_pid,
149 SMB_BIG_UINT count,SMB_BIG_UINT offset)
153 if (!lp_locking(SNUM(conn)))
156 if (!OPEN_FSP(fsp) || !fsp->can_lock || (fsp->conn != conn)) {
157 return NT_STATUS_INVALID_HANDLE;
160 DEBUG(10,("do_unlock: unlock start=%.0f len=%.0f requested for file %s\n",
161 (double)offset, (double)count, fsp->fsp_name ));
164 * Remove the existing lock record from the tdb lockdb
165 * before looking at POSIX locks. If this record doesn't
166 * match then don't bother looking to remove POSIX locks.
169 ok = brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
170 lock_pid, sys_getpid(), conn->cnum, offset, count);
173 DEBUG(10,("do_unlock: returning ERRlock.\n" ));
174 return NT_STATUS_LOCK_NOT_GRANTED;
177 if (!lp_posix_locking(SNUM(conn)))
180 (void)release_posix_lock(fsp, offset, count);
185 /****************************************************************************
186 Remove any locks on this fd. Called from file_close().
187 ****************************************************************************/
189 void locking_close_file(files_struct *fsp)
191 pid_t pid = sys_getpid();
193 if (!lp_locking(SNUM(fsp->conn)))
197 * Just release all the brl locks, no need to release individually.
200 brl_close(fsp->dev, fsp->inode, pid, fsp->conn->cnum, fsp->fnum);
202 if(lp_posix_locking(SNUM(fsp->conn))) {
205 * Release all the POSIX locks.
207 posix_locking_close_file(fsp);
212 /****************************************************************************
213 Initialise the locking functions.
214 ****************************************************************************/
216 static int open_read_only;
218 BOOL locking_init(int read_only)
225 tdb = tdb_open_log(lock_path("locking.tdb"),
226 0, TDB_DEFAULT|(read_only?0x0:TDB_CLEAR_IF_FIRST),
227 read_only?O_RDONLY:O_RDWR|O_CREAT,
231 DEBUG(0,("ERROR: Failed to initialise locking database\n"));
235 if (!posix_locking_init(read_only))
238 open_read_only = read_only;
243 /*******************************************************************
244 Deinitialize the share_mode management.
245 ******************************************************************/
247 BOOL locking_end(void)
250 brl_shutdown(open_read_only);
253 if (tdb_close(tdb) != 0)
260 /*******************************************************************
261 Form a static locking key for a dev/inode pair.
262 ******************************************************************/
264 static TDB_DATA locking_key(SMB_DEV_T dev, SMB_INO_T inode)
266 static struct locking_key key;
269 memset(&key, '\0', sizeof(key));
272 kbuf.dptr = (char *)&key;
273 kbuf.dsize = sizeof(key);
277 static TDB_DATA locking_key_fsp(files_struct *fsp)
279 return locking_key(fsp->dev, fsp->inode);
282 /*******************************************************************
283 Lock a hash bucket entry.
284 ******************************************************************/
286 BOOL lock_share_entry(connection_struct *conn,
287 SMB_DEV_T dev, SMB_INO_T inode)
289 return tdb_chainlock(tdb, locking_key(dev, inode)) == 0;
292 /*******************************************************************
293 Unlock a hash bucket entry.
294 ******************************************************************/
296 void unlock_share_entry(connection_struct *conn,
297 SMB_DEV_T dev, SMB_INO_T inode)
299 tdb_chainunlock(tdb, locking_key(dev, inode));
302 /*******************************************************************
303 Lock a hash bucket entry. use a fsp for convenience
304 ******************************************************************/
306 BOOL lock_share_entry_fsp(files_struct *fsp)
308 return tdb_chainlock(tdb, locking_key(fsp->dev, fsp->inode)) == 0;
311 /*******************************************************************
312 Unlock a hash bucket entry.
313 ******************************************************************/
315 void unlock_share_entry_fsp(files_struct *fsp)
317 tdb_chainunlock(tdb, locking_key(fsp->dev, fsp->inode));
320 /*******************************************************************
321 Print out a share mode.
322 ********************************************************************/
324 static char *share_mode_str(int num, share_mode_entry *e)
326 static pstring share_str;
328 slprintf(share_str, sizeof(share_str)-1, "share_mode_entry[%d]: \
329 pid = %u, share_mode = 0x%x, port = 0x%x, type= 0x%x, file_id = %lu, dev = 0x%x, inode = %.0f",
330 num, e->pid, e->share_mode, e->op_port, e->op_type, e->share_file_id,
331 (unsigned int)e->dev, (double)e->inode );
336 /*******************************************************************
337 Print out a share mode table.
338 ********************************************************************/
340 static void print_share_mode_table(struct locking_data *data)
342 int num_share_modes = data->u.num_share_mode_entries;
343 share_mode_entry *shares = (share_mode_entry *)(data + 1);
346 for (i = 0; i < num_share_modes; i++) {
347 share_mode_entry *entry_p = &shares[i];
348 DEBUG(10,("print_share_mode_table: %s\n", share_mode_str(i, entry_p) ));
352 /*******************************************************************
353 Get all share mode entries for a dev/inode pair.
354 ********************************************************************/
356 int get_share_modes(connection_struct *conn,
357 SMB_DEV_T dev, SMB_INO_T inode,
358 share_mode_entry **pp_shares)
361 struct locking_data *data;
363 share_mode_entry *shares = NULL;
367 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
371 data = (struct locking_data *)dbuf.dptr;
372 num_share_modes = data->u.num_share_mode_entries;
373 if(num_share_modes) {
377 shares = (share_mode_entry *)memdup(dbuf.dptr + sizeof(*data),
378 num_share_modes * sizeof(share_mode_entry));
381 SAFE_FREE(dbuf.dptr);
386 * Ensure that each entry has a real process attached.
389 for (i = 0; i < num_share_modes; ) {
390 share_mode_entry *entry_p = &shares[i];
391 if (process_exists(entry_p->pid)) {
392 DEBUG(10,("get_share_modes: %s\n", share_mode_str(i, entry_p) ));
395 DEBUG(10,("get_share_modes: deleted %s\n", share_mode_str(i, entry_p) ));
396 memcpy( &shares[i], &shares[i+1],
397 sizeof(share_mode_entry) * (num_share_modes - i - 1));
403 /* Did we delete any ? If so, re-store in tdb. */
405 data->u.num_share_mode_entries = num_share_modes;
408 memcpy(dbuf.dptr + sizeof(*data), shares,
409 num_share_modes * sizeof(share_mode_entry));
411 /* The record has shrunk a bit */
412 dbuf.dsize -= del_count * sizeof(share_mode_entry);
414 if (tdb_store(tdb, locking_key(dev, inode), dbuf, TDB_REPLACE) == -1) {
416 SAFE_FREE(dbuf.dptr);
422 SAFE_FREE(dbuf.dptr);
424 return num_share_modes;
427 /*******************************************************************
428 Fill a share mode entry.
429 ********************************************************************/
431 static void fill_share_mode(char *p, files_struct *fsp, uint16 port, uint16 op_type)
433 share_mode_entry *e = (share_mode_entry *)p;
434 void *x = &e->time; /* Needed to force alignment. p may not be aligned.... */
436 memset(e, '\0', sizeof(share_mode_entry));
437 e->pid = sys_getpid();
438 e->share_mode = fsp->share_mode;
440 e->op_type = op_type;
441 memcpy(x, &fsp->open_time, sizeof(struct timeval));
442 e->share_file_id = fsp->file_id;
444 e->inode = fsp->inode;
447 /*******************************************************************
448 Check if two share mode entries are identical, ignoring oplock
450 ********************************************************************/
452 BOOL share_modes_identical( share_mode_entry *e1, share_mode_entry *e2)
454 #if 1 /* JRA PARANOIA TEST - REMOVE LATER */
455 if (e1->pid == e2->pid &&
456 e1->share_file_id == e2->share_file_id &&
457 e1->dev == e2->dev &&
458 e1->inode == e2->inode &&
459 (e1->share_mode & ~DELETE_ON_CLOSE_FLAG) != (e2->share_mode & ~DELETE_ON_CLOSE_FLAG)) {
460 DEBUG(0,("PANIC: share_modes_identical: share_mode missmatch (e1 = %u, e2 = %u). Logic error.\n",
461 (unsigned int)(e1->share_mode & ~DELETE_ON_CLOSE_FLAG),
462 (unsigned int)(e2->share_mode & ~DELETE_ON_CLOSE_FLAG) ));
463 smb_panic("PANIC: share_modes_identical logic error.\n");
467 return (e1->pid == e2->pid &&
468 (e1->share_mode & ~DELETE_ON_CLOSE_FLAG) == (e2->share_mode & ~DELETE_ON_CLOSE_FLAG) &&
469 e1->dev == e2->dev &&
470 e1->inode == e2->inode &&
471 e1->share_file_id == e2->share_file_id );
474 /*******************************************************************
475 Delete a specific share mode. Return the number
476 of entries left, and a memdup'ed copy of the entry deleted (if required).
477 Ignore if no entry deleted.
478 ********************************************************************/
480 ssize_t del_share_entry( SMB_DEV_T dev, SMB_INO_T inode,
481 share_mode_entry *entry, share_mode_entry **ppse)
484 struct locking_data *data;
486 share_mode_entry *shares;
492 /* read in the existing share modes */
493 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
497 data = (struct locking_data *)dbuf.dptr;
498 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
501 * Find any with this pid and delete it
502 * by overwriting with the rest of the data
506 DEBUG(10,("del_share_entry: num_share_modes = %d\n", data->u.num_share_mode_entries ));
508 for (i=0;i<data->u.num_share_mode_entries;) {
509 if (share_modes_identical(&shares[i], entry)) {
510 DEBUG(10,("del_share_entry: deleted %s\n",
511 share_mode_str(i, &shares[i]) ));
513 *ppse = memdup(&shares[i], sizeof(*shares));
514 data->u.num_share_mode_entries--;
515 memmove(&shares[i], &shares[i+1],
516 dbuf.dsize - (sizeof(*data) + (i+1)*sizeof(*shares)));
519 DEBUG(10,("del_share_entry: deleting entry %d\n", i ));
527 /* the record may have shrunk a bit */
528 dbuf.dsize -= del_count * sizeof(*shares);
530 count = (ssize_t)data->u.num_share_mode_entries;
532 /* store it back in the database */
533 if (data->u.num_share_mode_entries == 0) {
534 if (tdb_delete(tdb, locking_key(dev, inode)) == -1)
537 if (tdb_store(tdb, locking_key(dev, inode), dbuf, TDB_REPLACE) == -1)
541 DEBUG(10,("del_share_entry: Remaining table.\n"));
542 print_share_mode_table((struct locking_data *)dbuf.dptr);
543 SAFE_FREE(dbuf.dptr);
547 /*******************************************************************
548 Del the share mode of a file for this process. Return the number
549 of entries left, and a memdup'ed copy of the entry deleted.
550 ********************************************************************/
552 ssize_t del_share_mode(files_struct *fsp, share_mode_entry **ppse)
554 share_mode_entry entry;
557 * Fake up a share_mode_entry for comparisons.
560 fill_share_mode((char *)&entry, fsp, 0, 0);
561 return del_share_entry(fsp->dev, fsp->inode, &entry, ppse);
564 /*******************************************************************
565 Set the share mode of a file. Return False on fail, True on success.
566 ********************************************************************/
568 BOOL set_share_mode(files_struct *fsp, uint16 port, uint16 op_type)
571 struct locking_data *data;
576 /* read in the existing share modes if any */
577 dbuf = tdb_fetch(tdb, locking_key_fsp(fsp));
579 /* we'll need to create a new record */
582 pstrcpy(fname, fsp->conn->connectpath);
584 pstrcat(fname, fsp->fsp_name);
586 size = sizeof(*data) + sizeof(share_mode_entry) + strlen(fname) + 1;
587 p = (char *)malloc(size);
590 data = (struct locking_data *)p;
591 data->u.num_share_mode_entries = 1;
593 DEBUG(10,("set_share_mode: creating entry for file %s. num_share_modes = 1\n",
596 pstrcpy(p + sizeof(*data) + sizeof(share_mode_entry), fname);
597 fill_share_mode(p + sizeof(*data), fsp, port, op_type);
600 if (tdb_store(tdb, locking_key_fsp(fsp), dbuf, TDB_REPLACE) == -1)
603 print_share_mode_table((struct locking_data *)p);
609 /* we're adding to an existing entry - this is a bit fiddly */
610 data = (struct locking_data *)dbuf.dptr;
612 data->u.num_share_mode_entries++;
614 DEBUG(10,("set_share_mode: adding entry for file %s. new num_share_modes = %d\n",
615 fsp->fsp_name, data->u.num_share_mode_entries ));
617 size = dbuf.dsize + sizeof(share_mode_entry);
621 memcpy(p, dbuf.dptr, sizeof(*data));
622 fill_share_mode(p + sizeof(*data), fsp, port, op_type);
623 memcpy(p + sizeof(*data) + sizeof(share_mode_entry), dbuf.dptr + sizeof(*data),
624 dbuf.dsize - sizeof(*data));
625 SAFE_FREE(dbuf.dptr);
628 if (tdb_store(tdb, locking_key_fsp(fsp), dbuf, TDB_REPLACE) == -1)
630 print_share_mode_table((struct locking_data *)p);
635 /*******************************************************************
636 A generic in-place modification call for share mode entries.
637 ********************************************************************/
639 static BOOL mod_share_mode( SMB_DEV_T dev, SMB_INO_T inode, share_mode_entry *entry,
640 void (*mod_fn)(share_mode_entry *, SMB_DEV_T, SMB_INO_T, void *),
644 struct locking_data *data;
646 share_mode_entry *shares;
647 BOOL need_store=False;
649 /* read in the existing share modes */
650 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
654 data = (struct locking_data *)dbuf.dptr;
655 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
657 /* find any with our pid and call the supplied function */
658 for (i=0;i<data->u.num_share_mode_entries;i++) {
659 if (share_modes_identical(entry, &shares[i])) {
660 mod_fn(&shares[i], dev, inode, param);
665 /* if the mod fn was called then store it back */
667 if (data->u.num_share_mode_entries == 0) {
668 if (tdb_delete(tdb, locking_key(dev, inode)) == -1)
671 if (tdb_store(tdb, locking_key(dev, inode), dbuf, TDB_REPLACE) == -1)
676 SAFE_FREE(dbuf.dptr);
680 /*******************************************************************
681 Static function that actually does the work for the generic function
683 ********************************************************************/
685 static void remove_share_oplock_fn(share_mode_entry *entry, SMB_DEV_T dev, SMB_INO_T inode,
688 DEBUG(10,("remove_share_oplock_fn: removing oplock info for entry dev=%x ino=%.0f\n",
689 (unsigned int)dev, (double)inode ));
690 /* Delete the oplock info. */
692 entry->op_type = NO_OPLOCK;
695 /*******************************************************************
696 Remove an oplock port and mode entry from a share mode.
697 ********************************************************************/
699 BOOL remove_share_oplock(files_struct *fsp)
701 share_mode_entry entry;
703 * Fake up an entry for comparisons...
705 fill_share_mode((char *)&entry, fsp, 0, 0);
706 return mod_share_mode(fsp->dev, fsp->inode, &entry, remove_share_oplock_fn, NULL);
709 /*******************************************************************
710 Static function that actually does the work for the generic function
712 ********************************************************************/
714 static void downgrade_share_oplock_fn(share_mode_entry *entry, SMB_DEV_T dev, SMB_INO_T inode,
717 DEBUG(10,("downgrade_share_oplock_fn: downgrading oplock info for entry dev=%x ino=%.0f\n",
718 (unsigned int)dev, (double)inode ));
719 entry->op_type = LEVEL_II_OPLOCK;
722 /*******************************************************************
723 Downgrade a oplock type from exclusive to level II.
724 ********************************************************************/
726 BOOL downgrade_share_oplock(files_struct *fsp)
728 share_mode_entry entry;
730 * Fake up an entry for comparisons...
732 fill_share_mode((char *)&entry, fsp, 0, 0);
733 return mod_share_mode(fsp->dev, fsp->inode, &entry, downgrade_share_oplock_fn, NULL);
736 /*******************************************************************
737 Get/Set the delete on close flag in a set of share modes.
738 Return False on fail, True on success.
739 ********************************************************************/
741 BOOL modify_delete_flag( SMB_DEV_T dev, SMB_INO_T inode, BOOL delete_on_close)
744 struct locking_data *data;
746 share_mode_entry *shares;
748 /* read in the existing share modes */
749 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
753 data = (struct locking_data *)dbuf.dptr;
754 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
756 /* Set/Unset the delete on close element. */
757 for (i=0;i<data->u.num_share_mode_entries;i++,shares++) {
758 shares->share_mode = (delete_on_close ?
759 (shares->share_mode | DELETE_ON_CLOSE_FLAG) :
760 (shares->share_mode & ~DELETE_ON_CLOSE_FLAG) );
764 if (data->u.num_share_mode_entries) {
765 if (tdb_store(tdb, locking_key(dev,inode), dbuf, TDB_REPLACE)==-1) {
766 SAFE_FREE(dbuf.dptr);
771 SAFE_FREE(dbuf.dptr);
775 /****************************************************************************
776 Traverse the whole database with this function, calling traverse_callback
778 ****************************************************************************/
780 static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf,
783 struct locking_data *data;
784 share_mode_entry *shares;
788 SHAREMODE_FN(traverse_callback) = (SHAREMODE_FN_CAST())state;
790 data = (struct locking_data *)dbuf.dptr;
791 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
792 name = dbuf.dptr + sizeof(*data) + data->u.num_share_mode_entries*sizeof(*shares);
794 for (i=0;i<data->u.num_share_mode_entries;i++) {
795 traverse_callback(&shares[i], name);
800 /*******************************************************************
801 Call the specified function on each entry under management by the
803 ********************************************************************/
805 int share_mode_forall(SHAREMODE_FN(fn))
809 return tdb_traverse(tdb, traverse_fn, (void*)fn);