/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 1997, 1998
* Sleepycat Software. All rights reserved.
*/
/*
* Copyright (c) 1990, 1993, 1994, 1995, 1996
* Keith Bostic. All rights reserved.
*/
/*
* Copyright (c) 1990, 1993, 1994, 1995
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Mike Olson.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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 "config.h"
#ifndef lint
static const char sccsid[] = "@(#)bt_page.c 10.17 (Sleepycat) 1/3/99";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <errno.h>
#include <string.h>
#endif
#include "db_int.h"
#include "db_page.h"
#include "btree.h"
/*
* __bam_new --
* Get a new page, preferably from the freelist.
*
* PUBLIC: int __bam_new __P((DBC *, u_int32_t, PAGE **));
*/
int
__bam_new(dbc, type, pagepp)
DBC *dbc;
u_int32_t type;
PAGE **pagepp;
{
BTMETA *meta;
DB *dbp;
DB_LOCK metalock;
PAGE *h;
db_pgno_t pgno;
int ret;
dbp = dbc->dbp;
meta = NULL;
h = NULL;
metalock = LOCK_INVALID;
pgno = PGNO_METADATA;
if ((ret = __bam_lget(dbc, 0, pgno, DB_LOCK_WRITE, &metalock)) != 0)
goto err;
if ((ret = memp_fget(dbp->mpf, &pgno, 0, (PAGE **)&meta)) != 0)
goto err;
if (meta->free == PGNO_INVALID) {
if ((ret = memp_fget(dbp->mpf, &pgno, DB_MPOOL_NEW, &h)) != 0)
goto err;
ZERO_LSN(h->lsn);
h->pgno = pgno;
} else {
pgno = meta->free;
if ((ret = memp_fget(dbp->mpf, &pgno, 0, &h)) != 0)
goto err;
meta->free = h->next_pgno;
}
/* Log the change. */
if (DB_LOGGING(dbc)) {
if ((ret = __bam_pg_alloc_log(dbp->dbenv->lg_info, dbc->txn,
&meta->lsn, 0, dbp->log_fileid, &meta->lsn, &h->lsn,
h->pgno, (u_int32_t)type, meta->free)) != 0)
goto err;
LSN(h) = LSN(meta);
}
(void)memp_fput(dbp->mpf, (PAGE *)meta, DB_MPOOL_DIRTY);
(void)__BT_TLPUT(dbc, metalock);
P_INIT(h, dbp->pgsize, h->pgno, PGNO_INVALID, PGNO_INVALID, 0, type);
*pagepp = h;
return (0);
err: if (h != NULL)
(void)memp_fput(dbp->mpf, h, 0);
if (meta != NULL)
(void)memp_fput(dbp->mpf, meta, 0);
if (metalock != LOCK_INVALID)
(void)__BT_TLPUT(dbc, metalock);
return (ret);
}
/*
* __bam_lput --
* The standard lock put call.
*
* PUBLIC: int __bam_lput __P((DBC *, DB_LOCK));
*/
int
__bam_lput(dbc, lock)
DBC *dbc;
DB_LOCK lock;
{
return (__BT_LPUT(dbc, lock));
}
/*
* __bam_free --
* Add a page to the head of the freelist.
*
* PUBLIC: int __bam_free __P((DBC *, PAGE *));
*/
int
__bam_free(dbc, h)
DBC *dbc;
PAGE *h;
{
BTMETA *meta;
DB *dbp;
DBT ldbt;
DB_LOCK metalock;
db_pgno_t pgno;
u_int32_t dirty_flag;
int ret, t_ret;
dbp = dbc->dbp;
/*
* Retrieve the metadata page and insert the page at the head of
* the free list. If either the lock get or page get routines
* fail, then we need to put the page with which we were called
* back because our caller assumes we take care of it.
*/
dirty_flag = 0;
pgno = PGNO_METADATA;
if ((ret = __bam_lget(dbc, 0, pgno, DB_LOCK_WRITE, &metalock)) != 0)
goto err;
if ((ret = memp_fget(dbp->mpf, &pgno, 0, (PAGE **)&meta)) != 0) {
(void)__BT_TLPUT(dbc, metalock);
goto err;
}
/* Log the change. */
if (DB_LOGGING(dbc)) {
memset(&ldbt, 0, sizeof(ldbt));
ldbt.data = h;
ldbt.size = P_OVERHEAD;
if ((ret = __bam_pg_free_log(dbp->dbenv->lg_info,
dbc->txn, &meta->lsn, 0, dbp->log_fileid, h->pgno,
&meta->lsn, &ldbt, meta->free)) != 0) {
(void)memp_fput(dbp->mpf, (PAGE *)meta, 0);
(void)__BT_TLPUT(dbc, metalock);
return (ret);
}
LSN(h) = LSN(meta);
}
/*
* The page should have nothing interesting on it, re-initialize it,
* leaving only the page number and the LSN.
*/
#ifdef DIAGNOSTIC
{ db_pgno_t __pgno; DB_LSN __lsn;
__pgno = h->pgno;
__lsn = h->lsn;
memset(h, 0xdb, dbp->pgsize);
h->pgno = __pgno;
h->lsn = __lsn;
}
#endif
P_INIT(h, dbp->pgsize, h->pgno, PGNO_INVALID, meta->free, 0, P_INVALID);
/* Link the page on the metadata free list. */
meta->free = h->pgno;
/* Discard the metadata page. */
ret = memp_fput(dbp->mpf, (PAGE *)meta, DB_MPOOL_DIRTY);
if ((t_ret = __BT_TLPUT(dbc, metalock)) != 0)
ret = t_ret;
/* Discard the caller's page reference. */
dirty_flag = DB_MPOOL_DIRTY;
err: if ((t_ret = memp_fput(dbp->mpf, h, dirty_flag)) != 0 && ret == 0)
ret = t_ret;
/*
* XXX
* We have to unlock the caller's page in the caller!
*/
return (ret);
}
#ifdef DEBUG
/*
* __bam_lt --
* Print out the list of locks currently held by a cursor.
*
* PUBLIC: int __bam_lt __P((DBC *));
*/
int
__bam_lt(dbc)
DBC *dbc;
{
DB *dbp;
DB_LOCKREQ req;
dbp = dbc->dbp;
if (F_ISSET(dbp, DB_AM_LOCKING)) {
req.op = DB_LOCK_DUMP;
lock_vec(dbp->dbenv->lk_info, dbc->locker, 0, &req, 1, NULL);
}
return (0);
}
#endif
/*
* __bam_lget --
* The standard lock get call.
*
* PUBLIC: int __bam_lget
* PUBLIC: __P((DBC *, int, db_pgno_t, db_lockmode_t, DB_LOCK *));
*/
int
__bam_lget(dbc, do_couple, pgno, mode, lockp)
DBC *dbc;
int do_couple;
db_pgno_t pgno;
db_lockmode_t mode;
DB_LOCK *lockp;
{
DB *dbp;
DB_LOCKREQ couple[2];
int ret;
dbp = dbc->dbp;
if (!F_ISSET(dbp, DB_AM_LOCKING)) {
*lockp = LOCK_INVALID;
return (0);
}
dbc->lock.pgno = pgno;
/*
* If the object not currently locked, acquire the lock and return,
* otherwise, lock couple. If we fail and it's not a system error,
* convert to EAGAIN.
*/
if (do_couple) {
couple[0].op = DB_LOCK_GET;
couple[0].obj = &dbc->lock_dbt;
couple[0].mode = mode;
couple[1].op = DB_LOCK_PUT;
couple[1].lock = *lockp;
if (dbc->txn == NULL)
ret = lock_vec(dbp->dbenv->lk_info,
dbc->locker, 0, couple, 2, NULL);
else
ret = lock_tvec(dbp->dbenv->lk_info,
dbc->txn, 0, couple, 2, NULL);
if (ret != 0) {
/* If we fail, discard the lock we held. */
__BT_LPUT(dbc, *lockp);
return (ret < 0 ? EAGAIN : ret);
}
*lockp = couple[0].lock;
} else {
if (dbc->txn == NULL)
ret = lock_get(dbp->dbenv->lk_info,
dbc->locker, 0, &dbc->lock_dbt, mode, lockp);
else
ret = lock_tget(dbp->dbenv->lk_info,
dbc->txn, 0, &dbc->lock_dbt, mode, lockp);
return (ret < 0 ? EAGAIN : ret);
}
return (0);
}