X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb%2Ftransaction.c;h=11194773647e255f1a7c8743cd69d5c85bfeda59;hp=04e4bbcd2e574820cf2edbde0e0c2233a2952960;hb=729fc5b931c8eb26f192399d8aa7064f9af058df;hpb=d92b8a7d9a050eb9735e48a8d37a5833500242d3 diff --git a/ccan/tdb/transaction.c b/ccan/tdb/transaction.c index 04e4bbcd..11194773 100644 --- a/ccan/tdb/transaction.c +++ b/ccan/tdb/transaction.c @@ -135,9 +135,6 @@ struct tdb_transaction { bool prepared; tdb_off_t magic_offset; - /* set when the OPEN_LOCK has been taken */ - bool open_lock_taken; - /* old file size before transaction */ tdb_len_t old_map_size; @@ -411,30 +408,12 @@ static int transaction_expand_file(struct tdb_context *tdb, tdb_off_t size, return 0; } -/* - brlock during a transaction - ignore them -*/ -static int transaction_brlock(struct tdb_context *tdb, - int rw_type, tdb_off_t offset, size_t len, - enum tdb_lock_flags flags) -{ - return 0; -} - -static int transaction_brunlock(struct tdb_context *tdb, - int rw_type, tdb_off_t offset, size_t len) -{ - return 0; -} - static const struct tdb_methods transaction_methods = { transaction_read, transaction_write, transaction_next_hash_chain, transaction_oob, transaction_expand_file, - transaction_brlock, - transaction_brunlock }; /* @@ -466,8 +445,8 @@ static int transaction_sync(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t return 0; } -/* ltype is F_WRLCK after prepare. */ -int _tdb_transaction_cancel(struct tdb_context *tdb, int ltype) + +static int _tdb_transaction_cancel(struct tdb_context *tdb) { int i, ret = 0; @@ -504,33 +483,12 @@ int _tdb_transaction_cancel(struct tdb_context *tdb, int ltype) } } - if (tdb->transaction->open_lock_taken) { - tdb_brunlock(tdb, F_WRLCK, OPEN_LOCK, 1); - tdb->transaction->open_lock_taken = false; - } - - /* remove any global lock created during the transaction */ - if (tdb->allrecord_lock.count != 0) { - tdb_brunlock(tdb, tdb->allrecord_lock.ltype, - FREELIST_TOP, 4*tdb->header.hash_size); - tdb->allrecord_lock.count = 0; - } - - /* remove any locks created during the transaction */ - if (tdb->num_locks != 0) { - for (i=0;inum_lockrecs;i++) { - tdb_brunlock(tdb, tdb->lockrecs[i].ltype, - tdb->lockrecs[i].off, 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; - tdb_brunlock(tdb, ltype, FREELIST_TOP, 0); tdb_transaction_unlock(tdb, F_WRLCK); SAFE_FREE(tdb->transaction->hash_heads); SAFE_FREE(tdb->transaction); @@ -603,10 +561,9 @@ int tdb_transaction_start(struct tdb_context *tdb) /* get a read lock from the freelist to the end of file. This is upgraded to a write lock during the commit */ - if (tdb_brlock(tdb, F_RDLCK, FREELIST_TOP, 0, TDB_LOCK_WAIT) == -1) { + if (tdb_allrecord_lock(tdb, F_RDLCK, TDB_LOCK_WAIT, true) == -1) { TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_start: failed to get hash locks\n")); - tdb->ecode = TDB_ERR_LOCK; - goto fail; + goto fail_allrecord_lock; } /* setup a copy of the hash table heads so the hash scan in @@ -639,7 +596,8 @@ int tdb_transaction_start(struct tdb_context *tdb) return 0; fail: - tdb_brunlock(tdb, F_RDLCK, FREELIST_TOP, 0); + tdb_allrecord_unlock(tdb, F_RDLCK, false); +fail_allrecord_lock: tdb_transaction_unlock(tdb, F_WRLCK); SAFE_FREE(tdb->transaction->blocks); SAFE_FREE(tdb->transaction->hash_heads); @@ -653,11 +611,8 @@ fail: */ int tdb_transaction_cancel(struct tdb_context *tdb) { - int ltype = F_RDLCK; tdb_trace(tdb, "tdb_transaction_cancel"); - if (tdb->transaction && tdb->transaction->prepared) - ltype = F_WRLCK; - return _tdb_transaction_cancel(tdb, ltype); + return _tdb_transaction_cancel(tdb); } /* @@ -707,10 +662,16 @@ static int tdb_recovery_allocate(struct tdb_context *tdb, rec.rec_len = 0; - if (recovery_head != 0 && - methods->tdb_read(tdb, recovery_head, &rec, sizeof(rec), DOCONV()) == -1) { - TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_recovery_allocate: failed to read recovery record\n")); - return -1; + if (recovery_head != 0) { + if (methods->tdb_read(tdb, recovery_head, &rec, sizeof(rec), DOCONV()) == -1) { + TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_recovery_allocate: failed to read recovery record\n")); + return -1; + } + /* ignore invalid recovery regions: can happen in crash */ + if (rec.magic != TDB_RECOVERY_MAGIC && + rec.magic != TDB_RECOVERY_INVALID_MAGIC) { + recovery_head = 0; + } } *recovery_size = tdb_recovery_size(tdb); @@ -917,14 +878,14 @@ static int _tdb_transaction_prepare_commit(struct tdb_context *tdb) if (tdb->transaction->prepared) { tdb->ecode = TDB_ERR_EINVAL; - _tdb_transaction_cancel(tdb, F_WRLCK); + _tdb_transaction_cancel(tdb); TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_prepare_commit: transaction already prepared\n")); return -1; } if (tdb->transaction->transaction_error) { tdb->ecode = TDB_ERR_IO; - _tdb_transaction_cancel(tdb, F_RDLCK); + _tdb_transaction_cancel(tdb); TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_prepare_commit: transaction error pending\n")); return -1; } @@ -947,34 +908,30 @@ static int _tdb_transaction_prepare_commit(struct tdb_context *tdb) 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); + _tdb_transaction_cancel(tdb); return -1; } /* upgrade the main transaction lock region to a write lock */ - if (tdb_brlock_upgrade(tdb, FREELIST_TOP, 0) == -1) { + if (tdb_allrecord_upgrade(tdb) == -1) { TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_prepare_commit: failed to upgrade hash locks\n")); - tdb->ecode = TDB_ERR_LOCK; - _tdb_transaction_cancel(tdb, F_RDLCK); + _tdb_transaction_cancel(tdb); return -1; } /* get the open lock - this prevents new users attaching to the database during the commit */ - if (tdb_brlock(tdb, F_WRLCK, OPEN_LOCK, 1, TDB_LOCK_WAIT) == -1) { + 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->ecode = TDB_ERR_LOCK; - _tdb_transaction_cancel(tdb, F_WRLCK); + _tdb_transaction_cancel(tdb); return -1; } - tdb->transaction->open_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) { TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction_prepare_commit: failed to setup recovery data\n")); - _tdb_transaction_cancel(tdb, F_WRLCK); + _tdb_transaction_cancel(tdb); return -1; } } @@ -988,7 +945,7 @@ static int _tdb_transaction_prepare_commit(struct tdb_context *tdb) tdb->transaction->old_map_size) == -1) { tdb->ecode = TDB_ERR_IO; TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction_prepare_commit: expansion failed\n")); - _tdb_transaction_cancel(tdb, F_WRLCK); + _tdb_transaction_cancel(tdb); return -1; } tdb->map_size = tdb->transaction->old_map_size; @@ -1040,7 +997,7 @@ int tdb_transaction_commit(struct tdb_context *tdb) /* check for a null transaction */ if (tdb->transaction->blocks == NULL) { - _tdb_transaction_cancel(tdb, F_RDLCK); + _tdb_transaction_cancel(tdb); return 0; } @@ -1076,7 +1033,7 @@ int tdb_transaction_commit(struct tdb_context *tdb) tdb->methods = methods; tdb_transaction_recover(tdb); - _tdb_transaction_cancel(tdb, F_WRLCK); + _tdb_transaction_cancel(tdb); TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction_commit: write failed\n")); return -1; @@ -1111,7 +1068,7 @@ int tdb_transaction_commit(struct tdb_context *tdb) /* use a transaction cancel to free memory and remove the transaction locks */ - _tdb_transaction_cancel(tdb, F_WRLCK); + _tdb_transaction_cancel(tdb); if (need_repack) { return tdb_repack(tdb); @@ -1225,16 +1182,6 @@ int tdb_transaction_recover(struct tdb_context *tdb) return -1; } - /* reduce the file size to the old size */ - tdb_munmap(tdb); - if (ftruncate(tdb->fd, recovery_eof) != 0) { - TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction_recover: failed to reduce to recovery size\n")); - tdb->ecode = TDB_ERR_IO; - return -1; - } - tdb->map_size = recovery_eof; - tdb_mmap(tdb); - if (transaction_sync(tdb, 0, recovery_eof) == -1) { TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction_recover: failed to sync2 recovery\n")); tdb->ecode = TDB_ERR_IO; @@ -1247,3 +1194,28 @@ int tdb_transaction_recover(struct tdb_context *tdb) /* all done */ return 0; } + +/* Any I/O failures we say "needs recovery". */ +bool tdb_needs_recovery(struct tdb_context *tdb) +{ + tdb_off_t recovery_head; + struct tdb_record rec; + + /* find the recovery area */ + if (tdb_ofs_read(tdb, TDB_RECOVERY_HEAD, &recovery_head) == -1) { + return true; + } + + if (recovery_head == 0) { + /* we have never allocated a recovery record */ + return false; + } + + /* read the recovery record */ + if (tdb->methods->tdb_read(tdb, recovery_head, &rec, + sizeof(rec), DOCONV()) == -1) { + return true; + } + + return (rec.magic == TDB_RECOVERY_MAGIC); +}