2 Unix SMB/Netbios implementation.
5 Copyright (C) Andrew Tridgell 1992-2000
6 Copyright (C) Jeremy Allison 1992-2000
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 12 aug 96: Erik.Devriendt@te6.siemens.be
25 added support for shared memory implementation of share mode locking
27 May 1997. Jeremy Allison (jallison@whistle.com). Modified share mode
28 locking to deal with multiple share modes per open file.
30 September 1997. Jeremy Allison (jallison@whistle.com). Added oplock
33 rewrtten completely to use new tdb code. Tridge, Dec '99
35 Added POSIX locking support. Jeremy Allison (jeremy@valinux.com), Apr. 2000.
39 extern int DEBUGLEVEL;
42 /* the locking database handle */
43 static TDB_CONTEXT *tdb;
45 /****************************************************************************
47 ****************************************************************************/
49 static const char *lock_type_name(enum brl_type lock_type)
51 return (lock_type == READ_LOCK) ? "READ" : "WRITE";
54 /****************************************************************************
55 Utility function called to see if a file region is locked.
56 If check_self is True, then checks on our own fd with the same locking context
57 are still made. If check_self is False, then checks are not made on our own fd
58 with the same locking context are not made.
59 ****************************************************************************/
61 BOOL is_locked(files_struct *fsp,connection_struct *conn,
62 SMB_BIG_UINT count,SMB_BIG_UINT offset,
63 enum brl_type lock_type, BOOL check_self)
65 int snum = SNUM(conn);
71 if (!lp_locking(snum) || !lp_strict_locking(snum))
74 ret = !brl_locktest(fsp->dev, fsp->inode, fsp->fnum,
75 global_smbpid, sys_getpid(), conn->cnum,
76 offset, count, lock_type, check_self);
78 DEBUG(10,("is_locked: brl start=%.0f len=%.0f %s for file %s\n",
79 (double)offset, (double)count, ret ? "locked" : "unlocked",
83 * There is no lock held by an SMB daemon, check to
84 * see if there is a POSIX lock from a UNIX or NFS process.
87 if(!ret && lp_posix_locking(snum)) {
88 ret = is_posix_locked(fsp, offset, count, lock_type);
90 DEBUG(10,("is_locked: posix start=%.0f len=%.0f %s for file %s\n",
91 (double)offset, (double)count, ret ? "locked" : "unlocked",
98 /****************************************************************************
99 Utility function called by locking requests.
100 ****************************************************************************/
102 NTSTATUS do_lock(files_struct *fsp,connection_struct *conn, uint16 lock_pid,
103 SMB_BIG_UINT count,SMB_BIG_UINT offset,enum brl_type lock_type)
107 if (!lp_locking(SNUM(conn)))
110 /* NOTE! 0 byte long ranges ARE allowed and should be stored */
113 DEBUG(10,("do_lock: lock type %s start=%.0f len=%.0f requested for file %s\n",
114 lock_type_name(lock_type), (double)offset, (double)count, fsp->fsp_name ));
116 if (OPEN_FSP(fsp) && fsp->can_lock && (fsp->conn == conn)) {
117 status = brl_lock(fsp->dev, fsp->inode, fsp->fnum,
118 lock_pid, sys_getpid(), conn->cnum,
122 if (NT_STATUS_IS_OK(status) && lp_posix_locking(SNUM(conn))) {
125 * Try and get a POSIX lock on this range.
126 * Note that this is ok if it is a read lock
127 * overlapping on a different fd. JRA.
130 if (!set_posix_lock(fsp, offset, count, lock_type)) {
131 status = NT_STATUS_LOCK_NOT_GRANTED;
133 * We failed to map - we must now remove the brl
136 (void)brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
137 lock_pid, sys_getpid(), conn->cnum,
146 /****************************************************************************
147 Utility function called by unlocking requests.
148 ****************************************************************************/
150 NTSTATUS do_unlock(files_struct *fsp,connection_struct *conn, uint16 lock_pid,
151 SMB_BIG_UINT count,SMB_BIG_UINT offset)
155 if (!lp_locking(SNUM(conn)))
158 if (!OPEN_FSP(fsp) || !fsp->can_lock || (fsp->conn != conn)) {
159 return NT_STATUS_INVALID_HANDLE;
162 DEBUG(10,("do_unlock: unlock start=%.0f len=%.0f requested for file %s\n",
163 (double)offset, (double)count, fsp->fsp_name ));
166 * Remove the existing lock record from the tdb lockdb
167 * before looking at POSIX locks. If this record doesn't
168 * match then don't bother looking to remove POSIX locks.
171 ok = brl_unlock(fsp->dev, fsp->inode, fsp->fnum,
172 lock_pid, sys_getpid(), conn->cnum, offset, count);
175 DEBUG(10,("do_unlock: returning ERRlock.\n" ));
176 return NT_STATUS_LOCK_NOT_GRANTED;
179 if (!lp_posix_locking(SNUM(conn)))
182 (void)release_posix_lock(fsp, offset, count);
187 /****************************************************************************
188 Remove any locks on this fd. Called from file_close().
189 ****************************************************************************/
191 void locking_close_file(files_struct *fsp)
193 pid_t pid = sys_getpid();
195 if (!lp_locking(SNUM(fsp->conn)))
199 * Just release all the brl locks, no need to release individually.
202 brl_close(fsp->dev, fsp->inode, pid, fsp->conn->cnum, fsp->fnum);
204 if(lp_posix_locking(SNUM(fsp->conn))) {
207 * Release all the POSIX locks.
209 posix_locking_close_file(fsp);
214 /****************************************************************************
215 Delete a record if it is for a dead process, if check_self is true, then
216 delete any records belonging to this pid also (there shouldn't be any).
217 This function is only called on locking startup and shutdown.
218 ****************************************************************************/
220 static int delete_fn(TDB_CONTEXT *ttdb, TDB_DATA kbuf, TDB_DATA dbuf, void *state)
222 struct locking_data *data;
223 share_mode_entry *shares;
225 pid_t mypid = sys_getpid();
226 BOOL check_self = *(BOOL *)state;
229 tdb_chainlock(tdb, kbuf);
231 data = (struct locking_data *)dbuf.dptr;
232 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
234 for (i=0;i<data->num_share_mode_entries;) {
236 if (check_self && (shares[i].pid == mypid)) {
237 DEBUG(0,("locking : delete_fn. LOGIC ERROR ! Shutting down and a record for my pid (%u) exists !\n",
238 (unsigned int)shares[i].pid ));
239 } else if (!process_exists(shares[i].pid)) {
240 DEBUG(0,("locking : delete_fn. LOGIC ERROR ! Entry for pid %u and it no longer exists !\n",
241 (unsigned int)shares[i].pid ));
243 /* Process exists, leave this record alone. */
248 data->num_share_mode_entries--;
249 memmove(&shares[i], &shares[i+1],
250 dbuf.dsize - (sizeof(*data) + (i+1)*sizeof(*shares)));
255 /* the record has shrunk a bit */
256 dbuf.dsize -= del_count * sizeof(*shares);
258 /* store it back in the database */
259 if (data->num_share_mode_entries == 0) {
260 if (tdb_delete(ttdb, kbuf) == -1)
263 if (tdb_store(ttdb, kbuf, dbuf, TDB_REPLACE) == -1)
267 tdb_chainunlock(tdb, kbuf);
271 /****************************************************************************
272 Initialise the locking functions.
273 ****************************************************************************/
275 static int open_read_only;
277 BOOL locking_init(int read_only)
279 BOOL check_self = False;
286 tdb = tdb_open_log(lock_path("locking.tdb"),
287 0, TDB_DEFAULT|(read_only?0x0:TDB_CLEAR_IF_FIRST),
288 read_only?O_RDONLY:O_RDWR|O_CREAT,
292 DEBUG(0,("ERROR: Failed to initialise locking database\n"));
296 if (!posix_locking_init(read_only))
299 /* delete any dead locks */
301 tdb_traverse(tdb, delete_fn, &check_self);
303 open_read_only = read_only;
308 /*******************************************************************
309 Deinitialize the share_mode management.
310 ******************************************************************/
312 BOOL locking_end(void)
314 BOOL check_self = True;
316 brl_shutdown(open_read_only);
319 /* delete any dead locks */
322 tdb_traverse(tdb, delete_fn, &check_self);
324 if (tdb_close(tdb) != 0)
331 /*******************************************************************
332 Form a static locking key for a dev/inode pair.
333 ******************************************************************/
335 static TDB_DATA locking_key(SMB_DEV_T dev, SMB_INO_T inode)
337 static struct locking_key key;
340 memset(&key, '\0', sizeof(key));
343 kbuf.dptr = (char *)&key;
344 kbuf.dsize = sizeof(key);
348 static TDB_DATA locking_key_fsp(files_struct *fsp)
350 return locking_key(fsp->dev, fsp->inode);
353 #ifndef LOCK_SHARE_ENTRY_SPIN_COUNT
354 #define LOCK_SHARE_ENTRY_SPIN_COUNT 100
357 /*******************************************************************
358 Lock a hash bucket entry.
359 ******************************************************************/
361 BOOL lock_share_entry(connection_struct *conn,
362 SMB_DEV_T dev, SMB_INO_T inode)
366 for (count = 0; count < LOCK_SHARE_ENTRY_SPIN_COUNT; count++)
367 if (tdb_chainlock(tdb, locking_key(dev, inode)) == 0)
370 DEBUG(0,("lock_share_entry: locking (%d) for dev = %x, inode = %.0f failed with error %s\n",
371 count, (unsigned int)dev, (double)inode, strerror(errno) ));
374 return tdb_chainlock(tdb, locking_key(dev, inode)) == 0;
378 /*******************************************************************
379 Unlock a hash bucket entry.
380 ******************************************************************/
382 void unlock_share_entry(connection_struct *conn,
383 SMB_DEV_T dev, SMB_INO_T inode)
385 tdb_chainunlock(tdb, locking_key(dev, inode));
388 /*******************************************************************
389 Lock a hash bucket entry. use a fsp for convenience
390 ******************************************************************/
392 BOOL lock_share_entry_fsp(files_struct *fsp)
396 for (count = 0; count < LOCK_SHARE_ENTRY_SPIN_COUNT; count++)
397 if (tdb_chainlock(tdb, locking_key(fsp->dev, fsp->inode)) == 0)
400 DEBUG(0,("lock_share_entry_fsp: locking (%d) for dev = %x, inode = %.0f failed with error %s\n",
401 count, (unsigned int)fsp->dev, (double)fsp->inode, strerror(errno) ));
404 return tdb_chainlock(tdb, locking_key(fsp->dev, fsp->inode)) == 0;
408 /*******************************************************************
409 Unlock a hash bucket entry.
410 ******************************************************************/
412 void unlock_share_entry_fsp(files_struct *fsp)
414 tdb_chainunlock(tdb, locking_key(fsp->dev, fsp->inode));
417 /*******************************************************************
418 Get all share mode entries for a dev/inode pair.
419 ********************************************************************/
421 int get_share_modes(connection_struct *conn,
422 SMB_DEV_T dev, SMB_INO_T inode,
423 share_mode_entry **shares)
426 struct locking_data *data;
431 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
435 data = (struct locking_data *)dbuf.dptr;
436 ret = data->num_share_mode_entries;
438 *shares = (share_mode_entry *)memdup(dbuf.dptr + sizeof(*data), ret * sizeof(**shares));
447 /*******************************************************************
448 Fill a share mode entry.
449 ********************************************************************/
451 static void fill_share_mode(char *p, files_struct *fsp, uint16 port, uint16 op_type)
453 share_mode_entry *e = (share_mode_entry *)p;
454 memset(e, '\0', sizeof(share_mode_entry));
455 e->pid = sys_getpid();
456 e->share_mode = fsp->share_mode;
458 e->op_type = op_type;
459 memcpy((char *)&e->time, (char *)&fsp->open_time, sizeof(struct timeval));
462 /*******************************************************************
463 Check if two share mode entries are identical, ignoring oplock
465 ********************************************************************/
467 BOOL share_modes_identical( share_mode_entry *e1, share_mode_entry *e2)
469 return (e1->pid == e2->pid &&
470 (e1->share_mode & ~DELETE_ON_CLOSE_FLAG) == (e2->share_mode & ~DELETE_ON_CLOSE_FLAG) &&
471 e1->time.tv_sec == e2->time.tv_sec &&
472 e1->time.tv_usec == e2->time.tv_usec );
475 /*******************************************************************
476 Delete a specific share mode. Return the number
477 of entries left, and a memdup'ed copy of the entry deleted (if required).
478 Ignore if no entry deleted.
479 ********************************************************************/
481 ssize_t del_share_entry( SMB_DEV_T dev, SMB_INO_T inode,
482 share_mode_entry *entry, share_mode_entry **ppse)
485 struct locking_data *data;
487 share_mode_entry *shares;
493 /* read in the existing share modes */
494 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
498 data = (struct locking_data *)dbuf.dptr;
499 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
502 * Find any with this pid and delete it
503 * by overwriting with the rest of the data
507 DEBUG(10,("del_share_mode: num_share_modes = %d\n", data->num_share_mode_entries ));
509 for (i=0;i<data->num_share_mode_entries;) {
510 if (share_modes_identical(&shares[i], entry)) {
512 *ppse = memdup(&shares[i], sizeof(*shares));
513 data->num_share_mode_entries--;
514 memmove(&shares[i], &shares[i+1],
515 dbuf.dsize - (sizeof(*data) + (i+1)*sizeof(*shares)));
518 DEBUG(10,("del_share_mode: deleting entry %d\n", i ));
526 /* the record may have shrunk a bit */
527 dbuf.dsize -= del_count * sizeof(*shares);
529 count = (ssize_t)data->num_share_mode_entries;
531 /* store it back in the database */
532 if (data->num_share_mode_entries == 0) {
533 if (tdb_delete(tdb, locking_key(dev, inode)) == -1)
536 if (tdb_store(tdb, locking_key(dev, inode), dbuf, TDB_REPLACE) == -1)
544 /*******************************************************************
545 Del the share mode of a file for this process. Return the number
546 of entries left, and a memdup'ed copy of the entry deleted.
547 ********************************************************************/
549 ssize_t del_share_mode(files_struct *fsp, share_mode_entry **ppse)
551 share_mode_entry entry;
554 * Fake up a share_mode_entry for comparisons.
557 fill_share_mode((char *)&entry, fsp, 0, 0);
558 return del_share_entry(fsp->dev, fsp->inode, &entry, ppse);
561 /*******************************************************************
562 Set the share mode of a file. Return False on fail, True on success.
563 ********************************************************************/
565 BOOL set_share_mode(files_struct *fsp, uint16 port, uint16 op_type)
568 struct locking_data *data;
573 /* read in the existing share modes if any */
574 dbuf = tdb_fetch(tdb, locking_key_fsp(fsp));
576 /* we'll need to create a new record */
579 pstrcpy(fname, fsp->conn->connectpath);
581 pstrcat(fname, fsp->fsp_name);
583 size = sizeof(*data) + sizeof(share_mode_entry) + strlen(fname) + 1;
584 p = (char *)malloc(size);
587 data = (struct locking_data *)p;
588 data->num_share_mode_entries = 1;
589 pstrcpy(p + sizeof(*data) + sizeof(share_mode_entry), fname);
590 fill_share_mode(p + sizeof(*data), fsp, port, op_type);
593 if (tdb_store(tdb, locking_key_fsp(fsp), dbuf, TDB_REPLACE) == -1)
599 /* we're adding to an existing entry - this is a bit fiddly */
600 data = (struct locking_data *)dbuf.dptr;
602 data->num_share_mode_entries++;
603 size = dbuf.dsize + sizeof(share_mode_entry);
607 memcpy(p, dbuf.dptr, sizeof(*data));
608 fill_share_mode(p + sizeof(*data), fsp, port, op_type);
609 memcpy(p + sizeof(*data) + sizeof(share_mode_entry), dbuf.dptr + sizeof(*data),
610 dbuf.dsize - sizeof(*data));
614 if (tdb_store(tdb, locking_key_fsp(fsp), dbuf, TDB_REPLACE) == -1)
620 /*******************************************************************
621 A generic in-place modification call for share mode entries.
622 ********************************************************************/
624 static BOOL mod_share_mode( SMB_DEV_T dev, SMB_INO_T inode, share_mode_entry *entry,
625 void (*mod_fn)(share_mode_entry *, SMB_DEV_T, SMB_INO_T, void *),
629 struct locking_data *data;
631 share_mode_entry *shares;
632 BOOL need_store=False;
634 /* read in the existing share modes */
635 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
639 data = (struct locking_data *)dbuf.dptr;
640 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
642 /* find any with our pid and call the supplied function */
643 for (i=0;i<data->num_share_mode_entries;i++) {
644 if (share_modes_identical(entry, &shares[i])) {
645 mod_fn(&shares[i], dev, inode, param);
650 /* if the mod fn was called then store it back */
652 if (data->num_share_mode_entries == 0) {
653 if (tdb_delete(tdb, locking_key(dev, inode)) == -1)
656 if (tdb_store(tdb, locking_key(dev, inode), dbuf, TDB_REPLACE) == -1)
665 /*******************************************************************
666 Static function that actually does the work for the generic function
668 ********************************************************************/
670 static void remove_share_oplock_fn(share_mode_entry *entry, SMB_DEV_T dev, SMB_INO_T inode,
673 DEBUG(10,("remove_share_oplock_fn: removing oplock info for entry dev=%x ino=%.0f\n",
674 (unsigned int)dev, (double)inode ));
675 /* Delete the oplock info. */
677 entry->op_type = NO_OPLOCK;
680 /*******************************************************************
681 Remove an oplock port and mode entry from a share mode.
682 ********************************************************************/
684 BOOL remove_share_oplock(files_struct *fsp)
686 share_mode_entry entry;
688 * Fake up an entry for comparisons...
690 fill_share_mode((char *)&entry, fsp, 0, 0);
691 return mod_share_mode(fsp->dev, fsp->inode, &entry, remove_share_oplock_fn, NULL);
694 /*******************************************************************
695 Static function that actually does the work for the generic function
697 ********************************************************************/
699 static void downgrade_share_oplock_fn(share_mode_entry *entry, SMB_DEV_T dev, SMB_INO_T inode,
702 DEBUG(10,("downgrade_share_oplock_fn: downgrading oplock info for entry dev=%x ino=%.0f\n",
703 (unsigned int)dev, (double)inode ));
704 entry->op_type = LEVEL_II_OPLOCK;
707 /*******************************************************************
708 Downgrade a oplock type from exclusive to level II.
709 ********************************************************************/
711 BOOL downgrade_share_oplock(files_struct *fsp)
713 share_mode_entry entry;
715 * Fake up an entry for comparisons...
717 fill_share_mode((char *)&entry, fsp, 0, 0);
718 return mod_share_mode(fsp->dev, fsp->inode, &entry, downgrade_share_oplock_fn, NULL);
721 /*******************************************************************
722 Get/Set the delete on close flag in a set of share modes.
723 Return False on fail, True on success.
724 ********************************************************************/
726 BOOL modify_delete_flag( SMB_DEV_T dev, SMB_INO_T inode, BOOL delete_on_close)
729 struct locking_data *data;
731 share_mode_entry *shares;
733 /* read in the existing share modes */
734 dbuf = tdb_fetch(tdb, locking_key(dev, inode));
738 data = (struct locking_data *)dbuf.dptr;
739 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
741 /* Set/Unset the delete on close element. */
742 for (i=0;i<data->num_share_mode_entries;i++,shares++) {
743 shares->share_mode = (delete_on_close ?
744 (shares->share_mode | DELETE_ON_CLOSE_FLAG) :
745 (shares->share_mode & ~DELETE_ON_CLOSE_FLAG) );
749 if (data->num_share_mode_entries) {
750 if (tdb_store(tdb, locking_key(dev,inode), dbuf, TDB_REPLACE)==-1) {
760 /****************************************************************************
761 Traverse the whole database with this function, calling traverse_callback
763 ****************************************************************************/
765 static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf,
768 struct locking_data *data;
769 share_mode_entry *shares;
773 SHAREMODE_FN(traverse_callback) = (SHAREMODE_FN_CAST())state;
775 data = (struct locking_data *)dbuf.dptr;
776 shares = (share_mode_entry *)(dbuf.dptr + sizeof(*data));
777 name = dbuf.dptr + sizeof(*data) + data->num_share_mode_entries*sizeof(*shares);
779 for (i=0;i<data->num_share_mode_entries;i++) {
780 traverse_callback(&shares[i], name);
785 /*******************************************************************
786 Call the specified function on each entry under management by the
788 ********************************************************************/
790 int share_mode_forall(SHAREMODE_FN(fn))
794 return tdb_traverse(tdb, traverse_fn, (void*)fn);