log_rec.c
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上传日期:2007-04-14
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文件大小:17k
- /*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996, 1997, 1998, 1999, 2000
- * Sleepycat Software. All rights reserved.
- */
- /*
- * Copyright (c) 1995, 1996
- * The President and Fellows of Harvard University. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
- #include "db_config.h"
- #ifndef lint
- static const char revid[] = "$Id: log_rec.c,v 11.48 2001/01/11 18:19:53 bostic Exp $";
- #endif /* not lint */
- #ifndef NO_SYSTEM_INCLUDES
- #include <sys/types.h>
- #include <string.h>
- #endif
- #include "db_int.h"
- #include "db_page.h"
- #include "db_am.h"
- #include "log.h"
- static int __log_check_master __P((DB_ENV *, u_int8_t *, char *));
- static int __log_do_open __P((DB_ENV *, DB_LOG *,
- u_int8_t *, char *, DBTYPE, int32_t, db_pgno_t));
- static int __log_open_file __P((DB_ENV *, DB_LOG *, __log_register_args *));
- /*
- * PUBLIC: int __log_register_recover
- * PUBLIC: __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
- */
- int
- __log_register_recover(dbenv, dbtp, lsnp, op, info)
- DB_ENV *dbenv;
- DBT *dbtp;
- DB_LSN *lsnp;
- db_recops op;
- void *info;
- {
- DB_ENTRY *dbe;
- DB_LOG *logp;
- DB *dbp;
- __log_register_args *argp;
- int do_rem, ret, t_ret;
- logp = dbenv->lg_handle;
- dbp = NULL;
- #ifdef DEBUG_RECOVER
- REC_PRINT(__log_register_print);
- #endif
- COMPQUIET(lsnp, NULL);
- if ((ret = __log_register_read(dbenv, dbtp->data, &argp)) != 0)
- goto out;
- if ((argp->opcode == LOG_OPEN &&
- (DB_REDO(op) || op == DB_TXN_OPENFILES)) ||
- (argp->opcode == LOG_CLOSE && DB_UNDO(op))) {
- /*
- * If we are redoing an open or undoing a close, then we need
- * to open a file. We must open the file even if
- * the meta page is not yet written as we may be creating it.
- */
- if (op == DB_TXN_OPENFILES)
- F_SET(logp, DBLOG_FORCE_OPEN);
- ret = __log_open_file(dbenv, logp, argp);
- F_CLR(logp, DBLOG_FORCE_OPEN);
- if (ret == ENOENT || ret == EINVAL) {
- if (op == DB_TXN_OPENFILES && argp->name.size != 0 &&
- (ret = __db_txnlist_delete(dbenv, info,
- argp->name.data, argp->fileid, 0)) != 0)
- goto out;
- ret = 0;
- }
- } else if (argp->opcode != LOG_CHECKPOINT) {
- /*
- * If we are undoing an open, then we need to close the file.
- *
- * If the file is deleted, then we can just ignore this close.
- * Otherwise, we should usually have a valid dbp we should
- * close or whose reference count should be decremented.
- * However, if we shut down without closing a file, we may, in
- * fact, not have the file open, and that's OK.
- */
- do_rem = 0;
- MUTEX_THREAD_LOCK(dbenv, logp->mutexp);
- if (argp->fileid < logp->dbentry_cnt) {
- dbe = &logp->dbentry[argp->fileid];
- DB_ASSERT(dbe->refcount == 1);
- ret = __db_txnlist_close(info,
- argp->fileid, dbe->count);
- if ((dbp = TAILQ_FIRST(&dbe->dblist)) != NULL)
- (void)log_unregister(dbenv, dbp);
- do_rem = 1;
- }
- MUTEX_THREAD_UNLOCK(dbenv, logp->mutexp);
- if (do_rem) {
- (void)__log_rem_logid(logp, dbp, argp->fileid);
- /*
- * If remove or rename has closed the file, don't
- * sync.
- */
- if (dbp != NULL &&
- (t_ret = dbp->close(dbp,
- dbp->mpf == NULL ? DB_NOSYNC : 0)) != 0 && ret == 0)
- ret = t_ret;
- }
- } else if (DB_UNDO(op) || op == DB_TXN_OPENFILES) {
- /*
- * It's a checkpoint and we are rolling backward. It
- * is possible that the system was shut down and thus
- * ended with a stable checkpoint; this file was never
- * closed and has therefore not been reopened yet. If
- * so, we need to try to open it.
- */
- ret = __log_open_file(dbenv, logp, argp);
- if (ret == ENOENT || ret == EINVAL) {
- if (argp->name.size != 0 && (ret =
- __db_txnlist_delete(dbenv, info,
- argp->name.data, argp->fileid, 0)) != 0)
- goto out;
- ret = 0;
- }
- }
- out: if (argp != NULL)
- __os_free(argp, 0);
- return (ret);
- }
- /*
- * __log_open_file --
- * Called during log_register recovery. Make sure that we have an
- * entry in the dbentry table for this ndx. Returns 0 on success,
- * non-zero on error.
- */
- static int
- __log_open_file(dbenv, lp, argp)
- DB_ENV *dbenv;
- DB_LOG *lp;
- __log_register_args *argp;
- {
- DB_ENTRY *dbe;
- DB *dbp;
- /*
- * We never re-open temporary files. Temp files are only
- * useful during aborts in which case the dbp was entered
- * when the file was registered. During recovery, we treat
- * temp files as properly deleted files, allowing the open to
- * fail and not reporting any errors when recovery fails to
- * get a valid dbp from db_fileid_to_db.
- */
- if (argp->name.size == 0) {
- (void)__log_add_logid(dbenv, lp, NULL, argp->fileid);
- return (ENOENT);
- }
- /*
- * Because of reference counting, we cannot automatically close files
- * during recovery, so when we're opening, we have to check that the
- * name we are opening is what we expect. If it's not, then we close
- * the old file and open the new one.
- */
- MUTEX_THREAD_LOCK(dbenv, lp->mutexp);
- if (argp->fileid < lp->dbentry_cnt)
- dbe = &lp->dbentry[argp->fileid];
- else
- dbe = NULL;
- if (dbe != NULL) {
- dbe->deleted = 0;
- if ((dbp = TAILQ_FIRST(&dbe->dblist)) != NULL) {
- if (dbp->meta_pgno != argp->meta_pgno ||
- memcmp(dbp->fileid,
- argp->uid.data, DB_FILE_ID_LEN) != 0) {
- MUTEX_THREAD_UNLOCK(dbenv, lp->mutexp);
- goto reopen;
- }
- if (!F_ISSET(lp, DBLOG_RECOVER))
- dbe->refcount++;
- MUTEX_THREAD_UNLOCK(dbenv, lp->mutexp);
- return (0);
- }
- }
- MUTEX_THREAD_UNLOCK(dbenv, lp->mutexp);
- if (0) {
- reopen: (void)log_unregister(dbp->dbenv, dbp);
- (void)__log_rem_logid(lp, dbp, argp->fileid);
- dbp->close(dbp, 0);
- }
- return (__log_do_open(dbenv, lp,
- argp->uid.data, argp->name.data,
- argp->ftype, argp->fileid, argp->meta_pgno));
- }
- /*
- * log_reopen_file -- close and reopen a db file.
- * Must be called when a metadata page changes.
- *
- * PUBLIC: int __log_reopen_file __P((DB_ENV *,
- * PUBLIC: char *, int32_t, u_int8_t *, db_pgno_t));
- *
- */
- int
- __log_reopen_file(dbenv, name, ndx, fileid, meta_pgno)
- DB_ENV *dbenv;
- char *name;
- int32_t ndx;
- u_int8_t *fileid;
- db_pgno_t meta_pgno;
- {
- DB *dbp;
- DB_LOG *logp;
- DBTYPE ftype;
- FNAME *fnp;
- LOG *lp;
- char *tmp_name;
- int ret;
- logp = dbenv->lg_handle;
- if (name == NULL) {
- R_LOCK(dbenv, &logp->reginfo);
- lp = logp->reginfo.primary;
- for (fnp = SH_TAILQ_FIRST(&lp->fq, __fname);
- fnp != NULL; fnp = SH_TAILQ_NEXT(fnp, q, __fname)) {
- if (fnp->ref == 0) /* Entry not in use. */
- continue;
- if (memcmp(fnp->ufid, fileid, DB_FILE_ID_LEN) == 0)
- break;
- }
- if (fnp == 0 || fnp->name_off == INVALID_ROFF) {
- __db_err(dbenv,
- "metasub recover: non-existent file id");
- return (EINVAL);
- }
- name = R_ADDR(&logp->reginfo, fnp->name_off);
- ret = __os_strdup(dbenv, name, &tmp_name);
- R_UNLOCK(dbenv, &logp->reginfo);
- if (ret != 0)
- goto out;
- name = tmp_name;
- } else
- tmp_name = NULL;
- if ((ret = __db_fileid_to_db(dbenv, &dbp, ndx, 0)) != 0)
- goto out;
- ftype = dbp->type;
- (void)log_unregister(dbenv, dbp);
- (void)__log_rem_logid(logp, dbp, ndx);
- (void)dbp->close(dbp, 0);
- ret = __log_do_open(dbenv, logp, fileid, name, ftype, ndx, meta_pgno);
- if (tmp_name != NULL)
- __os_free(tmp_name, 0);
- out: return (ret);
- }
- /*
- * __log_do_open --
- * Open files referenced in the log. This is the part of the open that
- * is not protected by the thread mutex.
- */
- static int
- __log_do_open(dbenv, lp, uid, name, ftype, ndx, meta_pgno)
- DB_ENV *dbenv;
- DB_LOG *lp;
- u_int8_t *uid;
- char *name;
- DBTYPE ftype;
- int32_t ndx;
- db_pgno_t meta_pgno;
- {
- DB *dbp;
- int ret;
- u_int8_t zeroid[DB_FILE_ID_LEN];
- if ((ret = db_create(&dbp, lp->dbenv, 0)) != 0)
- return (ret);
- dbp->log_fileid = ndx;
- /*
- * This is needed to signal to the locking routines called while
- * opening databases that we are potentially undoing a transaction
- * from an XA process. Since the XA process does not share
- * locks with the aborting transaction this prevents us from
- * deadlocking during the open during rollback.
- * Because this routine is called either during recovery or during an
- * XA_ABORT, we can safely set DB_AM_RECOVER in the dbp since it
- * will not be shared with other threads.
- */
- F_SET(dbp, DB_AM_RECOVER);
- if (meta_pgno != PGNO_BASE_MD)
- memcpy(dbp->fileid, uid, DB_FILE_ID_LEN);
- dbp->type = ftype;
- if ((ret =
- __db_dbopen(dbp, name, 0, __db_omode("rw----"), meta_pgno)) == 0) {
- /*
- * Verify that we are opening the same file that we were
- * referring to when we wrote this log record.
- */
- if (meta_pgno != PGNO_BASE_MD &&
- __log_check_master(dbenv, uid, name) != 0)
- goto not_right;
- if (memcmp(uid, dbp->fileid, DB_FILE_ID_LEN) != 0) {
- memset(zeroid, 0, DB_FILE_ID_LEN);
- if (memcmp(dbp->fileid, zeroid, DB_FILE_ID_LEN) != 0)
- goto not_right;
- memcpy(dbp->fileid, uid, DB_FILE_ID_LEN);
- }
- if (IS_RECOVERING(dbenv)) {
- (void)log_register(dbp->dbenv, dbp, name);
- (void)__log_add_logid(dbenv, lp, dbp, ndx);
- }
- return (0);
- }
- not_right:
- (void)dbp->close(dbp, 0);
- (void)__log_add_logid(dbenv, lp, NULL, ndx);
- return (ENOENT);
- }
- static int
- __log_check_master(dbenv, uid, name)
- DB_ENV *dbenv;
- u_int8_t *uid;
- char *name;
- {
- DB *dbp;
- int ret;
- ret = 0;
- if ((ret = db_create(&dbp, dbenv, 0)) != 0)
- return (ret);
- dbp->type = DB_BTREE;
- ret = __db_dbopen(dbp, name, 0, __db_omode("rw----"), PGNO_BASE_MD);
- if (ret == 0 && memcmp(uid, dbp->fileid, DB_FILE_ID_LEN) != 0)
- ret = EINVAL;
-
- (void) dbp->close(dbp, 0);
- return (ret);
- }
- /*
- * __log_add_logid --
- * Adds a DB entry to the log's DB entry table.
- *
- * PUBLIC: int __log_add_logid __P((DB_ENV *, DB_LOG *, DB *, int32_t));
- */
- int
- __log_add_logid(dbenv, logp, dbp, ndx)
- DB_ENV *dbenv;
- DB_LOG *logp;
- DB *dbp;
- int32_t ndx;
- {
- DB *dbtmp;
- int32_t i;
- int ret;
- ret = 0;
- MUTEX_THREAD_LOCK(dbenv, logp->mutexp);
- /*
- * Check if we need to grow the table. Note, ndx is 0-based (the
- * index into the DB entry table) an dbentry_cnt is 1-based, the
- * number of available slots.
- */
- if (logp->dbentry_cnt <= ndx) {
- if ((ret = __os_realloc(dbenv,
- (ndx + DB_GROW_SIZE) * sizeof(DB_ENTRY),
- NULL, &logp->dbentry)) != 0)
- goto err;
- /*
- * We have moved the head of the queue.
- * Fix up the queue header of an empty queue or the previous
- * pointer of the first element.
- */
- for (i = 0; i < logp->dbentry_cnt; i++) {
- if ((dbtmp =
- TAILQ_FIRST(&logp->dbentry[i].dblist)) == NULL)
- TAILQ_INIT(&logp->dbentry[i].dblist);
- else
- TAILQ_REINSERT_HEAD(
- &logp->dbentry[i].dblist, dbp, links);
- }
- /* Initialize the new entries. */
- for (i = logp->dbentry_cnt; i < ndx + DB_GROW_SIZE; i++) {
- logp->dbentry[i].count = 0;
- TAILQ_INIT(&logp->dbentry[i].dblist);
- logp->dbentry[i].deleted = 0;
- logp->dbentry[i].refcount = 0;
- }
- logp->dbentry_cnt = i;
- }
- if (logp->dbentry[ndx].deleted == 0 &&
- TAILQ_FIRST(&logp->dbentry[ndx].dblist) == NULL) {
- logp->dbentry[ndx].count = 0;
- if (dbp != NULL)
- TAILQ_INSERT_HEAD(&logp->dbentry[ndx].dblist,
- dbp, links);
- logp->dbentry[ndx].deleted = dbp == NULL;
- logp->dbentry[ndx].refcount = 1;
- } else if (!F_ISSET(logp, DBLOG_RECOVER)) {
- if (dbp != NULL)
- TAILQ_INSERT_HEAD(&logp->dbentry[ndx].dblist,
- dbp, links);
- logp->dbentry[ndx].refcount++;
- }
- err: MUTEX_THREAD_UNLOCK(dbenv, logp->mutexp);
- return (ret);
- }
- /*
- * __db_fileid_to_db --
- * Return the DB corresponding to the specified fileid.
- *
- * PUBLIC: int __db_fileid_to_db __P((DB_ENV *, DB **, int32_t, int));
- */
- int
- __db_fileid_to_db(dbenv, dbpp, ndx, inc)
- DB_ENV *dbenv;
- DB **dbpp;
- int32_t ndx;
- int inc;
- {
- DB_LOG *logp;
- DB *dbp;
- FNAME *fname;
- int ret;
- char *name;
- ret = 0;
- logp = dbenv->lg_handle;
- MUTEX_THREAD_LOCK(dbenv, logp->mutexp);
- /*
- * Under XA, a process different than the one issuing DB operations
- * may abort a transaction. In this case, recovery routines are run
- * by a process that does not necessarily have the file open, so we
- * we must open the file explicitly.
- */
- if (ndx >= logp->dbentry_cnt ||
- (!logp->dbentry[ndx].deleted &&
- (dbp = TAILQ_FIRST(&logp->dbentry[ndx].dblist)) == NULL)) {
- if (F_ISSET(logp, DBLOG_RECOVER)) {
- ret = ENOENT;
- goto err;
- }
- if (__log_lid_to_fname(logp, ndx, &fname) != 0) {
- /* Couldn't find entry; this is a fatal error. */
- __db_err(dbenv, "Missing log fileid entry");
- ret = EINVAL;
- goto err;
- }
- name = R_ADDR(&logp->reginfo, fname->name_off);
- /*
- * __log_do_open is called without protection of the
- * log thread lock.
- */
- MUTEX_THREAD_UNLOCK(dbenv, logp->mutexp);
- /*
- * At this point, we are not holding the thread lock, so exit
- * directly instead of going through the exit code at the
- * bottom. If the __log_do_open succeeded, then we don't need
- * to do any of the remaining error checking at the end of this
- * routine.
- */
- if ((ret = __log_do_open(dbenv, logp,
- fname->ufid, name, fname->s_type,
- ndx, fname->meta_pgno)) != 0)
- return (ret);
- *dbpp = TAILQ_FIRST(&logp->dbentry[ndx].dblist);
- return (0);
- }
- /*
- * Return DB_DELETED if the file has been deleted (it's not an error).
- */
- if (logp->dbentry[ndx].deleted) {
- ret = DB_DELETED;
- if (inc)
- logp->dbentry[ndx].count++;
- goto err;
- }
- /*
- * Otherwise return 0, but if we don't have a corresponding DB, it's
- * an error.
- */
- if ((*dbpp = TAILQ_FIRST(&logp->dbentry[ndx].dblist)) == NULL)
- ret = ENOENT;
- err: MUTEX_THREAD_UNLOCK(dbenv, logp->mutexp);
- return (ret);
- }
- /*
- * __log_close_files --
- * Close files that were opened by the recovery daemon. We sync the
- * file, unless its mpf pointer has been NULLed by a db_remove or
- * db_rename. We may not have flushed the log_register record that
- * closes the file.
- *
- * PUBLIC: void __log_close_files __P((DB_ENV *));
- */
- void
- __log_close_files(dbenv)
- DB_ENV *dbenv;
- {
- DB_ENTRY *dbe;
- DB_LOG *logp;
- DB *dbp;
- int32_t i;
- logp = dbenv->lg_handle;
- MUTEX_THREAD_LOCK(dbenv, logp->mutexp);
- for (i = 0; i < logp->dbentry_cnt; i++) {
- dbe = &logp->dbentry[i];
- while ((dbp = TAILQ_FIRST(&dbe->dblist)) != NULL) {
- (void)log_unregister(dbenv, dbp);
- TAILQ_REMOVE(&dbe->dblist, dbp, links);
- (void)dbp->close(dbp, dbp->mpf == NULL ? DB_NOSYNC : 0);
- }
- dbe->deleted = 0;
- dbe->refcount = 0;
- }
- MUTEX_THREAD_UNLOCK(dbenv, logp->mutexp);
- }
- /*
- * __log_rem_logid
- * Remove an entry from the log table. Find the appropriate DB and
- * unlink it from the linked list off the table. If the DB is NULL, treat
- * this as a simple refcount decrement.
- *
- * PUBLIC: void __log_rem_logid __P((DB_LOG *, DB *, int32_t));
- */
- void
- __log_rem_logid(logp, dbp, ndx)
- DB_LOG *logp;
- DB *dbp;
- int32_t ndx;
- {
- DB *xdbp;
- MUTEX_THREAD_LOCK(logp->dbenv, logp->mutexp);
- if (--logp->dbentry[ndx].refcount == 0) {
- TAILQ_INIT(&logp->dbentry[ndx].dblist);
- logp->dbentry[ndx].deleted = 0;
- } else if (dbp != NULL)
- for (xdbp = TAILQ_FIRST(&logp->dbentry[ndx].dblist);
- xdbp != NULL;
- xdbp = TAILQ_NEXT(xdbp, links))
- if (xdbp == dbp) {
- TAILQ_REMOVE(&logp->dbentry[ndx].dblist,
- xdbp, links);
- break;
- }
- MUTEX_THREAD_UNLOCK(logp->dbenv, logp->mutexp);
- }
- /*
- * __log_lid_to_fname --
- * Traverse the shared-memory region looking for the entry that
- * matches the passed log fileid. Returns 0 on success; -1 on error.
- * PUBLIC: int __log_lid_to_fname __P((DB_LOG *, int32_t, FNAME **));
- */
- int
- __log_lid_to_fname(dblp, lid, fnamep)
- DB_LOG *dblp;
- int32_t lid;
- FNAME **fnamep;
- {
- FNAME *fnp;
- LOG *lp;
- lp = dblp->reginfo.primary;
- for (fnp = SH_TAILQ_FIRST(&lp->fq, __fname);
- fnp != NULL; fnp = SH_TAILQ_NEXT(fnp, q, __fname)) {
- if (fnp->ref == 0) /* Entry not in use. */
- continue;
- if (fnp->id == lid) {
- *fnamep = fnp;
- return (0);
- }
- }
- return (-1);
- }