to reduce this to 3 or even 2 with some more work.
- check for a valid recovery record on open of the tdb, while the
- global lock is held. Automatically recover from the transaction
+ open lock is held. Automatically recover from the transaction
recovery area if needed, then continue with the open as
usual. This allows for smooth crash recovery with no administrator
intervention.
bool prepared;
tdb_off_t magic_offset;
- /* set when the GLOBAL_LOCK has been taken */
- bool global_lock_taken;
-
/* old file size before transaction */
tdb_len_t old_map_size;
int rw_type, tdb_off_t offset, size_t len,
enum tdb_lock_flags flags)
{
+ /* FIXME: We actually grab the open lock during a transaction. */
+ if (offset == OPEN_LOCK)
+ return tdb_brlock(tdb, rw_type, offset, len, flags);
return 0;
}
}
}
- if (tdb->transaction->global_lock_taken) {
- tdb_brunlock(tdb, F_WRLCK, GLOBAL_LOCK, 1);
- tdb->transaction->global_lock_taken = false;
- }
-
- /* remove any global lock created during the transaction */
- if (tdb->global_lock.count != 0) {
- tdb_brunlock(tdb, tdb->global_lock.ltype,
- FREELIST_TOP, 4*tdb->header.hash_size);
- tdb->global_lock.count = 0;
- }
-
- /* remove any locks created during the transaction */
- if (tdb->num_locks != 0) {
- for (i=0;i<tdb->num_lockrecs;i++) {
- tdb_brunlock(tdb, tdb->lockrecs[i].ltype,
- FREELIST_TOP+4*tdb->lockrecs[i].list, 1);
- }
- tdb->num_locks = 0;
- tdb->num_lockrecs = 0;
- SAFE_FREE(tdb->lockrecs);
- }
+ /* This also removes the OPEN_LOCK, if we have it. */
+ tdb_release_extra_locks(tdb);
/* restore the normal io methods */
tdb->methods = tdb->transaction->io_methods;
return 0;
}
- if (tdb->num_locks != 0 || tdb->global_lock.count) {
+ if (tdb_have_extra_locks(tdb)) {
/* the caller must not have any locks when starting a
transaction as otherwise we'll be screwed by lack
of nested locks in posix */
/* if there are any locks pending then the caller has not
nested their locks properly, so fail the transaction */
- if (tdb->num_locks || tdb->global_lock.count) {
+ if (tdb_have_extra_locks(tdb)) {
tdb->ecode = TDB_ERR_LOCK;
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_prepare_commit: locks pending on commit\n"));
_tdb_transaction_cancel(tdb, F_RDLCK);
return -1;
}
- /* get the global lock - this prevents new users attaching to the database
+ /* get the open lock - this prevents new users attaching to the database
during the commit */
- if (tdb_brlock(tdb, F_WRLCK, GLOBAL_LOCK, 1, TDB_LOCK_WAIT) == -1) {
- TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_prepare_commit: failed to get global lock\n"));
- tdb->ecode = TDB_ERR_LOCK;
+ if (tdb_nest_lock(tdb, OPEN_LOCK, F_WRLCK, TDB_LOCK_WAIT) == -1) {
+ TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_prepare_commit: failed to get open lock\n"));
_tdb_transaction_cancel(tdb, F_WRLCK);
return -1;
}
- tdb->transaction->global_lock_taken = true;
-
if (!(tdb->flags & TDB_NOSYNC)) {
/* write the recovery data to the end of the file */
if (transaction_setup_recovery(tdb, &tdb->transaction->magic_offset) == -1) {
methods->tdb_oob(tdb, tdb->map_size + 1, 1);
}
- /* Keep the global lock until the actual commit */
+ /* Keep the open lock until the actual commit */
return 0;
}
/*
recover from an aborted transaction. Must be called with exclusive
- database write access already established (including the global
+ database write access already established (including the open
lock to prevent new processes attaching)
*/
int tdb_transaction_recover(struct tdb_context *tdb)