/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1996-2004 * Sleepycat Software. All rights reserved. * * $Id: log_put.c,v 11.168 2004/10/15 16:59:42 bostic Exp $ */ #include "db_config.h" #ifndef NO_SYSTEM_INCLUDES #include #if TIME_WITH_SYS_TIME #include #include #else #if HAVE_SYS_TIME_H #include #else #include #endif #endif #include #include #endif #include "db_int.h" #include "dbinc/crypto.h" #include "dbinc/hmac.h" #include "dbinc/log.h" #include "dbinc/txn.h" static int __log_encrypt_record __P((DB_ENV *, DBT *, HDR *, u_int32_t)); static int __log_file __P((DB_ENV *, const DB_LSN *, char *, size_t)); static int __log_fill __P((DB_LOG *, DB_LSN *, void *, u_int32_t)); static int __log_flush_commit __P((DB_ENV *, const DB_LSN *, u_int32_t)); static int __log_newfh __P((DB_LOG *, int)); static int __log_put_next __P((DB_ENV *, DB_LSN *, const DBT *, HDR *, DB_LSN *)); static int __log_putr __P((DB_LOG *, DB_LSN *, const DBT *, u_int32_t, HDR *)); static int __log_write __P((DB_LOG *, void *, u_int32_t)); /* * __log_put_pp -- * DB_ENV->log_put pre/post processing. * * PUBLIC: int __log_put_pp __P((DB_ENV *, DB_LSN *, const DBT *, u_int32_t)); */ int __log_put_pp(dbenv, lsnp, udbt, flags) DB_ENV *dbenv; DB_LSN *lsnp; const DBT *udbt; u_int32_t flags; { int rep_check, ret; PANIC_CHECK(dbenv); ENV_REQUIRES_CONFIG(dbenv, dbenv->lg_handle, "DB_ENV->log_put", DB_INIT_LOG); /* Validate arguments: check for allowed flags. */ if ((ret = __db_fchk(dbenv, "DB_ENV->log_put", flags, DB_LOG_CHKPNT | DB_LOG_COMMIT | DB_FLUSH | DB_LOG_NOCOPY | DB_LOG_PERM | DB_LOG_WRNOSYNC)) != 0) return (ret); /* DB_LOG_WRNOSYNC and DB_FLUSH are mutually exclusive. */ if (LF_ISSET(DB_LOG_WRNOSYNC) && LF_ISSET(DB_FLUSH)) return (__db_ferr(dbenv, "DB_ENV->log_put", 1)); /* Replication clients should never write log records. */ if (IS_REP_CLIENT(dbenv)) { __db_err(dbenv, "DB_ENV->log_put is illegal on replication clients"); return (EINVAL); } rep_check = IS_ENV_REPLICATED(dbenv) ? 1 : 0; if (rep_check) __env_rep_enter(dbenv); ret = __log_put(dbenv, lsnp, udbt, flags); if (rep_check) __env_db_rep_exit(dbenv); return (ret); } /* * __log_put -- * DB_ENV->log_put. * * PUBLIC: int __log_put __P((DB_ENV *, DB_LSN *, const DBT *, u_int32_t)); */ int __log_put(dbenv, lsnp, udbt, flags) DB_ENV *dbenv; DB_LSN *lsnp; const DBT *udbt; u_int32_t flags; { DB_CIPHER *db_cipher; DBT *dbt, t; DB_LOG *dblp; DB_LSN lsn, old_lsn; HDR hdr; LOG *lp; int lock_held, need_free, ret; u_int8_t *key; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; db_cipher = dbenv->crypto_handle; dbt = &t; t = *udbt; lock_held = need_free = 0; ZERO_LSN(old_lsn); /* * If we are coming from the logging code, we use an internal flag, * DB_LOG_NOCOPY, because we know we can overwrite/encrypt the log * record in place. Otherwise, if a user called log_put then we * must copy it to new memory so that we know we can write it. * * We also must copy it to new memory if we are a replication master * so that we retain an unencrypted copy of the log record to send * to clients. */ if (!LF_ISSET(DB_LOG_NOCOPY) || IS_REP_MASTER(dbenv)) { if (CRYPTO_ON(dbenv)) t.size += db_cipher->adj_size(udbt->size); if ((ret = __os_calloc(dbenv, 1, t.size, &t.data)) != 0) goto err; need_free = 1; memcpy(t.data, udbt->data, udbt->size); } if ((ret = __log_encrypt_record(dbenv, dbt, &hdr, udbt->size)) != 0) goto err; if (CRYPTO_ON(dbenv)) key = db_cipher->mac_key; else key = NULL; /* Otherwise, we actually have a record to put. Put it. */ /* Before we grab the region lock, calculate the record's checksum. */ __db_chksum(dbt->data, dbt->size, key, hdr.chksum); R_LOCK(dbenv, &dblp->reginfo); lock_held = 1; if ((ret = __log_put_next(dbenv, &lsn, dbt, &hdr, &old_lsn)) != 0) goto panic_check; /* * If we are not a rep application, but are sharing a master rep env, * we should not be writing log records. */ if (IS_REP_MASTER(dbenv) && dbenv->rep_send == NULL) { __db_err(dbenv, "%s %s", "Non-replication DB_ENV handle attempting", "to modify a replicated environment"); ret = EINVAL; goto err; } /* * Assign the return LSN before dropping the region lock. Necessary * in case the lsn is a begin_lsn from a TXN_DETAIL structure passed * in by the logging routines. */ *lsnp = lsn; if (IS_REP_MASTER(dbenv)) { /* * Replication masters need to drop the lock to send messages, * but want to drop and reacquire it a minimal number of times. */ R_UNLOCK(dbenv, &dblp->reginfo); lock_held = 0; /* * If we changed files and we're in a replicated environment, * we need to inform our clients now that we've dropped the * region lock. * * Note that a failed NEWFILE send is a dropped message that * our client can handle, so we can ignore it. It's possible * that the record we already put is a commit, so we don't just * want to return failure. */ if (!IS_ZERO_LSN(old_lsn)) (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_NEWFILE, &old_lsn, NULL, 0); /* * Then send the log record itself on to our clients. * * If the send fails and we're a commit or checkpoint, * there's nothing we can do; the record's in the log. * Flush it, even if we're running with TXN_NOSYNC, on the * grounds that it should be in durable form somewhere. */ /* * !!! * In the crypto case, we MUST send the udbt, not the * now-encrypted dbt. Clients have no way to decrypt * without the header. */ if ((__rep_send_message(dbenv, DB_EID_BROADCAST, REP_LOG, &lsn, udbt, flags) != 0) && LF_ISSET(DB_LOG_PERM)) LF_SET(DB_FLUSH); } /* * If needed, do a flush. Note that failures at this point * are only permissible if we know we haven't written a commit * record; __log_flush_commit is responsible for enforcing this. * * If a flush is not needed, see if WRITE_NOSYNC was set and we * need to write out the log buffer. */ if (LF_ISSET(DB_FLUSH | DB_LOG_WRNOSYNC)) { if (!lock_held) { R_LOCK(dbenv, &dblp->reginfo); lock_held = 1; } if ((ret = __log_flush_commit(dbenv, &lsn, flags)) != 0) goto panic_check; } /* * If flushed a checkpoint record, reset the "bytes since the last * checkpoint" counters. */ if (LF_ISSET(DB_LOG_CHKPNT)) lp->stat.st_wc_bytes = lp->stat.st_wc_mbytes = 0; if (0) { panic_check: /* * Writing log records cannot fail if we're a replication * master. The reason is that once we send the record to * replication clients, the transaction can no longer * abort, otherwise the master would be out of sync with * the rest of the replication group. Panic the system. */ if (ret != 0 && IS_REP_MASTER(dbenv)) ret = __db_panic(dbenv, ret); } err: if (lock_held) R_UNLOCK(dbenv, &dblp->reginfo); if (need_free) __os_free(dbenv, dbt->data); /* * If auto-remove is set and we switched files, remove unnecessary * log files. */ if (ret == 0 && !IS_ZERO_LSN(old_lsn) && lp->db_log_autoremove) __log_autoremove(dbenv); return (ret); } /* * __log_txn_lsn -- * * PUBLIC: void __log_txn_lsn * PUBLIC: __P((DB_ENV *, DB_LSN *, u_int32_t *, u_int32_t *)); */ void __log_txn_lsn(dbenv, lsnp, mbytesp, bytesp) DB_ENV *dbenv; DB_LSN *lsnp; u_int32_t *mbytesp, *bytesp; { DB_LOG *dblp; LOG *lp; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; R_LOCK(dbenv, &dblp->reginfo); /* * We are trying to get the LSN of the last entry in the log. We use * this in two places: 1) DB_ENV->txn_checkpoint uses it as a first * value when trying to compute an LSN such that all transactions begun * before it are complete. 2) DB_ENV->txn_begin uses it as the * begin_lsn. * * Typically, it's easy to get the last written LSN, you simply look * at the current log pointer and back up the number of bytes of the * last log record. However, if the last thing we did was write the * log header of a new log file, then, this doesn't work, so we return * the first log record that will be written in this new file. */ *lsnp = lp->lsn; if (lp->lsn.offset > lp->len) lsnp->offset -= lp->len; /* * Since we're holding the log region lock, return the bytes put into * the log since the last checkpoint, transaction checkpoint needs it. * * We add the current buffer offset so as to count bytes that have not * yet been written, but are sitting in the log buffer. */ if (mbytesp != NULL) { *mbytesp = lp->stat.st_wc_mbytes; *bytesp = (u_int32_t)(lp->stat.st_wc_bytes + lp->b_off); } R_UNLOCK(dbenv, &dblp->reginfo); } /* * __log_put_next -- * Put the given record as the next in the log, wherever that may * turn out to be. */ static int __log_put_next(dbenv, lsn, dbt, hdr, old_lsnp) DB_ENV *dbenv; DB_LSN *lsn; const DBT *dbt; HDR *hdr; DB_LSN *old_lsnp; { DB_LOG *dblp; DB_LSN old_lsn; LOG *lp; int newfile, ret; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; /* * Save a copy of lp->lsn before we might decide to switch log * files and change it. If we do switch log files, and we're * doing replication, we'll need to tell our clients about the * switch, and they need to receive a NEWFILE message * with this "would-be" LSN in order to know they're not * missing any log records. */ old_lsn = lp->lsn; newfile = 0; /* * If this information won't fit in the file, or if we're a * replication client environment and have been told to do so, * swap files. */ if (lp->lsn.offset == 0 || lp->lsn.offset + hdr->size + dbt->size > lp->log_size) { if (hdr->size + sizeof(LOGP) + dbt->size > lp->log_size) { __db_err(dbenv, "DB_ENV->log_put: record larger than maximum file size (%lu > %lu)", (u_long)hdr->size + sizeof(LOGP) + dbt->size, (u_long)lp->log_size); return (EINVAL); } if ((ret = __log_newfile(dblp, NULL, 0)) != 0) return (ret); /* * Flag that we switched files, in case we're a master * and need to send this information to our clients. * We postpone doing the actual send until we can * safely release the log region lock and are doing so * anyway. */ newfile = 1; } /* * The offset into the log file at this point is the LSN where * we're about to put this record, and is the LSN the caller wants. */ *lsn = lp->lsn; /* If we switched log files, let our caller know where. */ if (newfile) *old_lsnp = old_lsn; /* Actually put the record. */ return (__log_putr(dblp, lsn, dbt, lp->lsn.offset - lp->len, hdr)); } /* * __log_flush_commit -- * Flush a record. */ static int __log_flush_commit(dbenv, lsnp, flags) DB_ENV *dbenv; const DB_LSN *lsnp; u_int32_t flags; { DB_LOG *dblp; DB_LSN flush_lsn; LOG *lp; int ret; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; flush_lsn = *lsnp; ret = 0; /* * DB_FLUSH: * Flush a record for which the DB_FLUSH flag to log_put was set. * * DB_LOG_WRNOSYNC: * If there's anything in the current log buffer, write it out. */ if (LF_ISSET(DB_FLUSH)) ret = __log_flush_int(dblp, &flush_lsn, 1); else if (!lp->db_log_inmemory && lp->b_off != 0) if ((ret = __log_write(dblp, dblp->bufp, (u_int32_t)lp->b_off)) == 0) lp->b_off = 0; /* * If a flush supporting a transaction commit fails, we must abort the * transaction. (If we aren't doing a commit, return the failure; if * if the commit we care about made it to disk successfully, we just * ignore the failure, because there's no way to undo the commit.) */ if (ret == 0 || !LF_ISSET(DB_LOG_COMMIT)) return (ret); if (flush_lsn.file != lp->lsn.file || flush_lsn.offset < lp->w_off) return (0); /* * Else, make sure that the commit record does not get out after we * abort the transaction. Do this by overwriting the commit record * in the buffer. (Note that other commits in this buffer will wait * wait until a successful write happens, we do not wake them.) We * point at the right part of the buffer and write an abort record * over the commit. We must then try and flush the buffer again, * since the interesting part of the buffer may have actually made * it out to disk before there was a failure, we can't know for sure. */ if (__txn_force_abort(dbenv, dblp->bufp + flush_lsn.offset - lp->w_off) == 0) (void)__log_flush_int(dblp, &flush_lsn, 0); return (ret); } /* * __log_newfile -- * Initialize and switch to a new log file. (Note that this is * called both when no log yet exists and when we fill a log file.) * * PUBLIC: int __log_newfile __P((DB_LOG *, DB_LSN *, u_int32_t)); */ int __log_newfile(dblp, lsnp, logfile) DB_LOG *dblp; DB_LSN *lsnp; u_int32_t logfile; { DB_CIPHER *db_cipher; DB_ENV *dbenv; DB_LSN lsn; DBT t; HDR hdr; LOG *lp; int need_free, ret; u_int32_t lastoff; size_t tsize; u_int8_t *tmp; dbenv = dblp->dbenv; lp = dblp->reginfo.primary; DB_ASSERT(logfile == 0 || logfile > lp->lsn.file); /* If we're not at the beginning of a file already, start a new one. */ if (lp->lsn.offset != 0) { /* * Flush the log so this file is out and can be closed. We * cannot release the region lock here because we need to * protect the end of the file while we switch. In * particular, a thread with a smaller record than ours * could detect that there is space in the log. Even * blocking that event by declaring the file full would * require all threads to wait here so that the lsn.file * can be moved ahead after the flush completes. This * probably can be changed if we had an lsn for the * previous file and one for the current, but it does not * seem like this would get much more throughput, if any. */ if ((ret = __log_flush_int(dblp, NULL, 0)) != 0) return (ret); /* * Save the last known offset from the previous file, we'll * need it to initialize the persistent header information. */ lastoff = lp->lsn.offset; /* Point the current LSN to the new file. */ ++lp->lsn.file; lp->lsn.offset = 0; /* Reset the file write offset. */ lp->w_off = 0; } else lastoff = 0; /* * Replication may require we reset the log file name space entirely. * In that case we also force a file switch so that replication can * clean up old files. */ if (logfile != 0) { lp->lsn.file = logfile; lp->lsn.offset = 0; if ((ret = __log_newfh(dblp, 1)) != 0) return (ret); } DB_ASSERT(lp->db_log_inmemory || lp->b_off == 0); if (lp->db_log_inmemory && (ret = __log_inmem_newfile(dblp, lp->lsn.file)) != 0) return (ret); /* * Insert persistent information as the first record in every file. * Note that the previous length is wrong for the very first record * of the log, but that's okay, we check for it during retrieval. */ memset(&t, 0, sizeof(t)); memset(&hdr, 0, sizeof(HDR)); need_free = 0; tsize = sizeof(LOGP); db_cipher = dbenv->crypto_handle; if (CRYPTO_ON(dbenv)) tsize += db_cipher->adj_size(tsize); if ((ret = __os_calloc(dbenv, 1, tsize, &tmp)) != 0) return (ret); lp->persist.log_size = lp->log_size = lp->log_nsize; memcpy(tmp, &lp->persist, sizeof(LOGP)); t.data = tmp; t.size = (u_int32_t)tsize; need_free = 1; if ((ret = __log_encrypt_record(dbenv, &t, &hdr, (u_int32_t)tsize)) != 0) goto err; __db_chksum(t.data, t.size, (CRYPTO_ON(dbenv)) ? db_cipher->mac_key : NULL, hdr.chksum); lsn = lp->lsn; if ((ret = __log_putr(dblp, &lsn, &t, lastoff == 0 ? 0 : lastoff - lp->len, &hdr)) != 0) goto err; /* Update the LSN information returned to the caller. */ if (lsnp != NULL) *lsnp = lp->lsn; err: if (need_free) __os_free(dbenv, tmp); return (ret); } /* * __log_putr -- * Actually put a record into the log. */ static int __log_putr(dblp, lsn, dbt, prev, h) DB_LOG *dblp; DB_LSN *lsn; const DBT *dbt; u_int32_t prev; HDR *h; { DB_CIPHER *db_cipher; DB_ENV *dbenv; DB_LSN f_lsn; LOG *lp; HDR tmp, *hdr; int ret, t_ret; size_t b_off, nr; u_int32_t w_off; dbenv = dblp->dbenv; lp = dblp->reginfo.primary; /* * If we weren't given a header, use a local one. */ db_cipher = dbenv->crypto_handle; if (h == NULL) { hdr = &tmp; memset(hdr, 0, sizeof(HDR)); if (CRYPTO_ON(dbenv)) hdr->size = HDR_CRYPTO_SZ; else hdr->size = HDR_NORMAL_SZ; } else hdr = h; /* Save our position in case we fail. */ b_off = lp->b_off; w_off = lp->w_off; f_lsn = lp->f_lsn; /* * Initialize the header. If we just switched files, lsn.offset will * be 0, and what we really want is the offset of the previous record * in the previous file. Fortunately, prev holds the value we want. */ hdr->prev = prev; hdr->len = (u_int32_t)hdr->size + dbt->size; /* * If we were passed in a nonzero checksum, our caller calculated * the checksum before acquiring the log mutex, as an optimization. * * If our caller calculated a real checksum of 0, we'll needlessly * recalculate it. C'est la vie; there's no out-of-bounds value * here. */ if (hdr->chksum[0] == 0) __db_chksum(dbt->data, dbt->size, (CRYPTO_ON(dbenv)) ? db_cipher->mac_key : NULL, hdr->chksum); if (lp->db_log_inmemory && (ret = __log_inmem_chkspace(dblp, (u_int32_t)hdr->size + dbt->size)) != 0) goto err; if ((ret = __log_fill(dblp, lsn, hdr, (u_int32_t)hdr->size)) != 0) goto err; if ((ret = __log_fill(dblp, lsn, dbt->data, dbt->size)) != 0) goto err; lp->len = (u_int32_t)(hdr->size + dbt->size); lp->lsn.offset += (u_int32_t)(hdr->size + dbt->size); return (0); err: /* * If we wrote more than one buffer before failing, get the * first one back. The extra buffers will fail the checksums * and be ignored. */ if (w_off + lp->buffer_size < lp->w_off) { DB_ASSERT(!lp->db_log_inmemory); if ((t_ret = __os_seek(dbenv, dblp->lfhp, 0, 0, w_off, 0, DB_OS_SEEK_SET)) != 0 || (t_ret = __os_read(dbenv, dblp->lfhp, dblp->bufp, b_off, &nr)) != 0) return (__db_panic(dbenv, t_ret)); if (nr != b_off) { __db_err(dbenv, "Short read while restoring log"); return (__db_panic(dbenv, EIO)); } } /* Reset to where we started. */ lp->w_off = w_off; lp->b_off = b_off; lp->f_lsn = f_lsn; return (ret); } /* * __log_flush_pp -- * DB_ENV->log_flush pre/post processing. * * PUBLIC: int __log_flush_pp __P((DB_ENV *, const DB_LSN *)); */ int __log_flush_pp(dbenv, lsn) DB_ENV *dbenv; const DB_LSN *lsn; { int rep_check, ret; PANIC_CHECK(dbenv); ENV_REQUIRES_CONFIG(dbenv, dbenv->lg_handle, "DB_ENV->log_flush", DB_INIT_LOG); rep_check = IS_ENV_REPLICATED(dbenv) ? 1 : 0; if (rep_check) __env_rep_enter(dbenv); ret = __log_flush(dbenv, lsn); if (rep_check) __env_db_rep_exit(dbenv); return (ret); } /* * __log_flush -- * DB_ENV->log_flush * * PUBLIC: int __log_flush __P((DB_ENV *, const DB_LSN *)); */ int __log_flush(dbenv, lsn) DB_ENV *dbenv; const DB_LSN *lsn; { DB_LOG *dblp; int ret; dblp = dbenv->lg_handle; R_LOCK(dbenv, &dblp->reginfo); ret = __log_flush_int(dblp, lsn, 1); R_UNLOCK(dbenv, &dblp->reginfo); return (ret); } /* * __log_flush_int -- * Write all records less than or equal to the specified LSN; internal * version. * * PUBLIC: int __log_flush_int __P((DB_LOG *, const DB_LSN *, int)); */ int __log_flush_int(dblp, lsnp, release) DB_LOG *dblp; const DB_LSN *lsnp; int release; { struct __db_commit *commit; DB_ENV *dbenv; DB_LSN flush_lsn, f_lsn; DB_MUTEX *flush_mutexp; LOG *lp; size_t b_off; u_int32_t ncommit, w_off; int do_flush, first, ret; dbenv = dblp->dbenv; lp = dblp->reginfo.primary; flush_mutexp = R_ADDR(&dblp->reginfo, lp->flush_mutex_off); ncommit = 0; ret = 0; if (lp->db_log_inmemory) { lp->s_lsn = lp->lsn; ++lp->stat.st_scount; return (0); } /* * If no LSN specified, flush the entire log by setting the flush LSN * to the last LSN written in the log. Otherwise, check that the LSN * isn't a non-existent record for the log. */ if (lsnp == NULL) { flush_lsn.file = lp->lsn.file; flush_lsn.offset = lp->lsn.offset - lp->len; } else if (lsnp->file > lp->lsn.file || (lsnp->file == lp->lsn.file && lsnp->offset > lp->lsn.offset - lp->len)) { __db_err(dbenv, "DB_ENV->log_flush: LSN of %lu/%lu past current end-of-log of %lu/%lu", (u_long)lsnp->file, (u_long)lsnp->offset, (u_long)lp->lsn.file, (u_long)lp->lsn.offset); __db_err(dbenv, "%s %s %s", "Database environment corrupt; the wrong log files may", "have been removed or incompatible database files imported", "from another environment"); return (__db_panic(dbenv, DB_RUNRECOVERY)); } else { /* * See if we need to wait. s_lsn is not locked so some * care is needed. The sync point can only move forward. * The lsnp->file cannot be greater than the s_lsn.file. * If the file we want is in the past we are done. * If the file numbers are the same check the offset. * This all assumes we can read an integer in one * state or the other, not in transition. */ if (lp->s_lsn.file > lsnp->file) return (0); if (lp->s_lsn.file == lsnp->file && lp->s_lsn.offset > lsnp->offset) return (0); flush_lsn = *lsnp; } /* * If a flush is in progress and we're allowed to do so, drop * the region lock and block waiting for the next flush. */ if (release && lp->in_flush != 0) { if ((commit = SH_TAILQ_FIRST( &lp->free_commits, __db_commit)) == NULL) { if ((ret = __db_shalloc(&dblp->reginfo, sizeof(struct __db_commit), MUTEX_ALIGN, &commit)) != 0) goto flush; memset(commit, 0, sizeof(*commit)); if ((ret = __db_mutex_setup(dbenv, &dblp->reginfo, &commit->mutex, MUTEX_SELF_BLOCK | MUTEX_NO_RLOCK)) != 0) { __db_shalloc_free(&dblp->reginfo, commit); return (ret); } MUTEX_LOCK(dbenv, &commit->mutex); } else SH_TAILQ_REMOVE( &lp->free_commits, commit, links, __db_commit); lp->ncommit++; /* * Flushes may be requested out of LSN order; be * sure we only move lp->t_lsn forward. */ if (log_compare(&lp->t_lsn, &flush_lsn) < 0) lp->t_lsn = flush_lsn; commit->lsn = flush_lsn; SH_TAILQ_INSERT_HEAD( &lp->commits, commit, links, __db_commit); R_UNLOCK(dbenv, &dblp->reginfo); /* Wait here for the in-progress flush to finish. */ MUTEX_LOCK(dbenv, &commit->mutex); R_LOCK(dbenv, &dblp->reginfo); lp->ncommit--; /* * Grab the flag before freeing the struct to see if * we need to flush the log to commit. If so, * use the maximal lsn for any committing thread. */ do_flush = F_ISSET(commit, DB_COMMIT_FLUSH); F_CLR(commit, DB_COMMIT_FLUSH); SH_TAILQ_INSERT_HEAD( &lp->free_commits, commit, links, __db_commit); if (do_flush) { lp->in_flush--; flush_lsn = lp->t_lsn; } else return (0); } /* * Protect flushing with its own mutex so we can release * the region lock except during file switches. */ flush: MUTEX_LOCK(dbenv, flush_mutexp); /* * If the LSN is less than or equal to the last-sync'd LSN, we're done. * Note, the last-sync LSN saved in s_lsn is the LSN of the first byte * after the byte we absolutely know was written to disk, so the test * is <, not <=. */ if (flush_lsn.file < lp->s_lsn.file || (flush_lsn.file == lp->s_lsn.file && flush_lsn.offset < lp->s_lsn.offset)) { MUTEX_UNLOCK(dbenv, flush_mutexp); goto done; } /* * We may need to write the current buffer. We have to write the * current buffer if the flush LSN is greater than or equal to the * buffer's starting LSN. * * Otherwise, it's still possible that this thread may never have * written to this log file. Acquire a file descriptor if we don't * already have one. */ if (lp->b_off != 0 && log_compare(&flush_lsn, &lp->f_lsn) >= 0) { if ((ret = __log_write(dblp, dblp->bufp, (u_int32_t)lp->b_off)) != 0) { MUTEX_UNLOCK(dbenv, flush_mutexp); goto done; } lp->b_off = 0; } else if (dblp->lfhp == NULL || dblp->lfname != lp->lsn.file) if ((ret = __log_newfh(dblp, 0)) != 0) { MUTEX_UNLOCK(dbenv, flush_mutexp); goto done; } /* * We are going to flush, release the region. * First get the current state of the buffer since * another write may come in, but we may not flush it. */ b_off = lp->b_off; w_off = lp->w_off; f_lsn = lp->f_lsn; lp->in_flush++; if (release) R_UNLOCK(dbenv, &dblp->reginfo); /* Sync all writes to disk. */ if ((ret = __os_fsync(dbenv, dblp->lfhp)) != 0) { MUTEX_UNLOCK(dbenv, flush_mutexp); if (release) R_LOCK(dbenv, &dblp->reginfo); ret = __db_panic(dbenv, ret); return (ret); } /* * Set the last-synced LSN. * This value must be set to the LSN past the last complete * record that has been flushed. This is at least the first * lsn, f_lsn. If the buffer is empty, b_off == 0, then * we can move up to write point since the first lsn is not * set for the new buffer. */ lp->s_lsn = f_lsn; if (b_off == 0) lp->s_lsn.offset = w_off; MUTEX_UNLOCK(dbenv, flush_mutexp); if (release) R_LOCK(dbenv, &dblp->reginfo); lp->in_flush--; ++lp->stat.st_scount; /* * How many flush calls (usually commits) did this call actually sync? * At least one, if it got here. */ ncommit = 1; done: if (lp->ncommit != 0) { first = 1; for (commit = SH_TAILQ_FIRST(&lp->commits, __db_commit); commit != NULL; commit = SH_TAILQ_NEXT(commit, links, __db_commit)) if (log_compare(&lp->s_lsn, &commit->lsn) > 0) { MUTEX_UNLOCK(dbenv, &commit->mutex); SH_TAILQ_REMOVE( &lp->commits, commit, links, __db_commit); ncommit++; } else if (first == 1) { F_SET(commit, DB_COMMIT_FLUSH); MUTEX_UNLOCK(dbenv, &commit->mutex); SH_TAILQ_REMOVE( &lp->commits, commit, links, __db_commit); /* * This thread will wake and flush. * If another thread commits and flushes * first we will waste a trip trough the * mutex. */ lp->in_flush++; first = 0; } } if (lp->stat.st_maxcommitperflush < ncommit) lp->stat.st_maxcommitperflush = ncommit; if (lp->stat.st_mincommitperflush > ncommit || lp->stat.st_mincommitperflush == 0) lp->stat.st_mincommitperflush = ncommit; return (ret); } /* * __log_fill -- * Write information into the log. */ static int __log_fill(dblp, lsn, addr, len) DB_LOG *dblp; DB_LSN *lsn; void *addr; u_int32_t len; { LOG *lp; u_int32_t bsize, nrec; size_t nw, remain; int ret; lp = dblp->reginfo.primary; bsize = lp->buffer_size; if (lp->db_log_inmemory) { __log_inmem_copyin(dblp, lp->b_off, addr, len); lp->b_off = (lp->b_off + len) % lp->buffer_size; return (0); } while (len > 0) { /* Copy out the data. */ /* * If we're beginning a new buffer, note the user LSN to which * the first byte of the buffer belongs. We have to know this * when flushing the buffer so that we know if the in-memory * buffer needs to be flushed. */ if (lp->b_off == 0) lp->f_lsn = *lsn; /* * If we're on a buffer boundary and the data is big enough, * copy as many records as we can directly from the data. */ if (lp->b_off == 0 && len >= bsize) { nrec = len / bsize; if ((ret = __log_write(dblp, addr, nrec * bsize)) != 0) return (ret); addr = (u_int8_t *)addr + nrec * bsize; len -= nrec * bsize; ++lp->stat.st_wcount_fill; continue; } /* Figure out how many bytes we can copy this time. */ remain = bsize - lp->b_off; nw = remain > len ? len : remain; memcpy(dblp->bufp + lp->b_off, addr, nw); addr = (u_int8_t *)addr + nw; len -= (u_int32_t)nw; lp->b_off += nw; /* If we fill the buffer, flush it. */ if (lp->b_off == bsize) { if ((ret = __log_write(dblp, dblp->bufp, bsize)) != 0) return (ret); lp->b_off = 0; ++lp->stat.st_wcount_fill; } } return (0); } /* * __log_write -- * Write the log buffer to disk. */ static int __log_write(dblp, addr, len) DB_LOG *dblp; void *addr; u_int32_t len; { DB_ENV *dbenv; LOG *lp; size_t nw; int ret; dbenv = dblp->dbenv; lp = dblp->reginfo.primary; DB_ASSERT(!lp->db_log_inmemory); /* * If we haven't opened the log file yet or the current one has * changed, acquire a new log file. We are creating the file if we're * about to write to the start of it, in other words, if the write * offset is zero. */ if (dblp->lfhp == NULL || dblp->lfname != lp->lsn.file) if ((ret = __log_newfh(dblp, lp->w_off == 0)) != 0) return (ret); /* * If we're writing the first block in a log file on a filesystem that * guarantees unwritten blocks are zero-filled, we set the size of the * file in advance. This increases sync performance on some systems, * because they don't need to update metadata on every sync. */ #ifdef HAVE_FILESYSTEM_NOTZERO if (lp->w_off == 0 && !__os_fs_notzero()) #else if (lp->w_off == 0) #endif ret = __db_fileinit(dbenv, dblp->lfhp, lp->log_size, 0); /* * Seek to the offset in the file (someone may have written it * since we last did). */ if ((ret = __os_seek(dbenv, dblp->lfhp, 0, 0, lp->w_off, 0, DB_OS_SEEK_SET)) != 0 || (ret = __os_write(dbenv, dblp->lfhp, addr, len, &nw)) != 0) return (ret); /* Reset the buffer offset and update the seek offset. */ lp->w_off += len; /* Update written statistics. */ if ((lp->stat.st_w_bytes += len) >= MEGABYTE) { lp->stat.st_w_bytes -= MEGABYTE; ++lp->stat.st_w_mbytes; } if ((lp->stat.st_wc_bytes += len) >= MEGABYTE) { lp->stat.st_wc_bytes -= MEGABYTE; ++lp->stat.st_wc_mbytes; } ++lp->stat.st_wcount; return (0); } /* * __log_file_pp -- * DB_ENV->log_file pre/post processing. * * PUBLIC: int __log_file_pp __P((DB_ENV *, const DB_LSN *, char *, size_t)); */ int __log_file_pp(dbenv, lsn, namep, len) DB_ENV *dbenv; const DB_LSN *lsn; char *namep; size_t len; { int rep_check, ret; PANIC_CHECK(dbenv); ENV_REQUIRES_CONFIG(dbenv, dbenv->lg_handle, "DB_ENV->log_file", DB_INIT_LOG); if (F_ISSET(dbenv, DB_ENV_LOG_INMEMORY)) { __db_err(dbenv, "DB_ENV->log_file is illegal with in-memory logs."); return (EINVAL); } rep_check = IS_ENV_REPLICATED(dbenv) ? 1 : 0; if (rep_check) __env_rep_enter(dbenv); ret = __log_file(dbenv, lsn, namep, len); if (rep_check) __env_db_rep_exit(dbenv); return (ret); } /* * __log_file -- * DB_ENV->log_file. */ static int __log_file(dbenv, lsn, namep, len) DB_ENV *dbenv; const DB_LSN *lsn; char *namep; size_t len; { DB_LOG *dblp; int ret; char *name; dblp = dbenv->lg_handle; R_LOCK(dbenv, &dblp->reginfo); ret = __log_name(dblp, lsn->file, &name, NULL, 0); R_UNLOCK(dbenv, &dblp->reginfo); if (ret != 0) return (ret); /* Check to make sure there's enough room and copy the name. */ if (len < strlen(name) + 1) { *namep = '\0'; __db_err(dbenv, "DB_ENV->log_file: name buffer is too short"); return (EINVAL); } (void)strcpy(namep, name); __os_free(dbenv, name); return (0); } /* * __log_newfh -- * Acquire a file handle for the current log file. */ static int __log_newfh(dblp, create) DB_LOG *dblp; int create; { DB_ENV *dbenv; LOG *lp; u_int32_t flags; int ret; logfile_validity status; dbenv = dblp->dbenv; lp = dblp->reginfo.primary; /* Close any previous file descriptor. */ if (dblp->lfhp != NULL) { (void)__os_closehandle(dbenv, dblp->lfhp); dblp->lfhp = NULL; } flags = DB_OSO_LOG | DB_OSO_SEQ | (create ? DB_OSO_CREATE : 0) | (F_ISSET(dbenv, DB_ENV_DIRECT_LOG) ? DB_OSO_DIRECT : 0) | (F_ISSET(dbenv, DB_ENV_DSYNC_LOG) ? DB_OSO_DSYNC : 0); /* Get the path of the new file and open it. */ dblp->lfname = lp->lsn.file; if ((ret = __log_valid(dblp, dblp->lfname, 0, &dblp->lfhp, flags, &status)) != 0) __db_err(dbenv, "DB_ENV->log_put: %d: %s", lp->lsn.file, db_strerror(ret)); else if (status != DB_LV_NORMAL && status != DB_LV_INCOMPLETE) ret = DB_NOTFOUND; return (ret); } /* * __log_name -- * Return the log name for a particular file, and optionally open it. * * PUBLIC: int __log_name __P((DB_LOG *, * PUBLIC: u_int32_t, char **, DB_FH **, u_int32_t)); */ int __log_name(dblp, filenumber, namep, fhpp, flags) DB_LOG *dblp; u_int32_t filenumber, flags; char **namep; DB_FH **fhpp; { DB_ENV *dbenv; LOG *lp; int ret; char *oname; char old[sizeof(LFPREFIX) + 5 + 20], new[sizeof(LFPREFIX) + 10 + 20]; dbenv = dblp->dbenv; lp = dblp->reginfo.primary; DB_ASSERT(!lp->db_log_inmemory); /* * !!! * The semantics of this routine are bizarre. * * The reason for all of this is that we need a place where we can * intercept requests for log files, and, if appropriate, check for * both the old-style and new-style log file names. The trick is * that all callers of this routine that are opening the log file * read-only want to use an old-style file name if they can't find * a match using a new-style name. The only down-side is that some * callers may check for the old-style when they really don't need * to, but that shouldn't mess up anything, and we only check for * the old-style name when we've already failed to find a new-style * one. * * Create a new-style file name, and if we're not going to open the * file, return regardless. */ (void)snprintf(new, sizeof(new), LFNAME, filenumber); if ((ret = __db_appname(dbenv, DB_APP_LOG, new, 0, NULL, namep)) != 0 || fhpp == NULL) return (ret); /* Open the new-style file -- if we succeed, we're done. */ if ((ret = __os_open_extend(dbenv, *namep, 0, flags, (int)lp->persist.mode, fhpp)) == 0) return (0); /* * The open failed... if the DB_RDONLY flag isn't set, we're done, * the caller isn't interested in old-style files. */ if (!LF_ISSET(DB_OSO_RDONLY)) { __db_err(dbenv, "%s: log file open failed: %s", *namep, db_strerror(ret)); return (__db_panic(dbenv, ret)); } /* Create an old-style file name. */ (void)snprintf(old, sizeof(old), LFNAME_V1, filenumber); if ((ret = __db_appname(dbenv, DB_APP_LOG, old, 0, NULL, &oname)) != 0) goto err; /* * Open the old-style file -- if we succeed, we're done. Free the * space allocated for the new-style name and return the old-style * name to the caller. */ if ((ret = __os_open(dbenv, oname, flags, (int)lp->persist.mode, fhpp)) == 0) { __os_free(dbenv, *namep); *namep = oname; return (0); } /* * Couldn't find either style of name -- return the new-style name * for the caller's error message. If it's an old-style name that's * actually missing we're going to confuse the user with the error * message, but that implies that not only were we looking for an * old-style name, but we expected it to exist and we weren't just * looking for any log file. That's not a likely error. */ err: __os_free(dbenv, oname); return (ret); } /* * __log_rep_put -- * Short-circuit way for replication clients to put records into the * log. Replication clients' logs need to be laid out exactly their masters' * are, so we let replication take responsibility for when the log gets * flushed, when log switches files, etc. This is just a thin PUBLIC wrapper * for __log_putr with a slightly prettier interface. * * Note that the db_rep->db_mutexp should be held when this is called. * Note that we acquire the log region lock while holding db_mutexp. * * PUBLIC: int __log_rep_put __P((DB_ENV *, DB_LSN *, const DBT *)); */ int __log_rep_put(dbenv, lsnp, rec) DB_ENV *dbenv; DB_LSN *lsnp; const DBT *rec; { DB_CIPHER *db_cipher; DB_LOG *dblp; HDR hdr; DBT *dbt, t; LOG *lp; int need_free, ret; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; R_LOCK(dbenv, &dblp->reginfo); memset(&hdr, 0, sizeof(HDR)); t = *rec; dbt = &t; need_free = 0; db_cipher = (DB_CIPHER *)dbenv->crypto_handle; if (CRYPTO_ON(dbenv)) t.size += db_cipher->adj_size(rec->size); if ((ret = __os_calloc(dbenv, 1, t.size, &t.data)) != 0) goto err; need_free = 1; memcpy(t.data, rec->data, rec->size); if ((ret = __log_encrypt_record(dbenv, dbt, &hdr, rec->size)) != 0) goto err; __db_chksum(t.data, t.size, (CRYPTO_ON(dbenv)) ? db_cipher->mac_key : NULL, hdr.chksum); DB_ASSERT(log_compare(lsnp, &lp->lsn) == 0); ret = __log_putr(dblp, lsnp, dbt, lp->lsn.offset - lp->len, &hdr); err: /* * !!! Assume caller holds db_rep->db_mutex to modify ready_lsn. */ lp->ready_lsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); if (need_free) __os_free(dbenv, t.data); return (ret); } static int __log_encrypt_record(dbenv, dbt, hdr, orig) DB_ENV *dbenv; DBT *dbt; HDR *hdr; u_int32_t orig; { DB_CIPHER *db_cipher; int ret; if (CRYPTO_ON(dbenv)) { db_cipher = (DB_CIPHER *)dbenv->crypto_handle; hdr->size = HDR_CRYPTO_SZ; hdr->orig_size = orig; if ((ret = db_cipher->encrypt(dbenv, db_cipher->data, hdr->iv, dbt->data, dbt->size)) != 0) return (ret); } else { hdr->size = HDR_NORMAL_SZ; } return (0); }