linux-sg2042/fs/xfs/libxfs/xfs_refcount.c

178 lines
4.9 KiB
C

/*
* Copyright (C) 2016 Oracle. All Rights Reserved.
*
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_btree.h"
#include "xfs_bmap.h"
#include "xfs_refcount_btree.h"
#include "xfs_alloc.h"
#include "xfs_error.h"
#include "xfs_trace.h"
#include "xfs_cksum.h"
#include "xfs_trans.h"
#include "xfs_bit.h"
#include "xfs_refcount.h"
/*
* Look up the first record less than or equal to [bno, len] in the btree
* given by cur.
*/
int
xfs_refcount_lookup_le(
struct xfs_btree_cur *cur,
xfs_agblock_t bno,
int *stat)
{
trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_private.a.agno, bno,
XFS_LOOKUP_LE);
cur->bc_rec.rc.rc_startblock = bno;
cur->bc_rec.rc.rc_blockcount = 0;
return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
}
/*
* Look up the first record greater than or equal to [bno, len] in the btree
* given by cur.
*/
int
xfs_refcount_lookup_ge(
struct xfs_btree_cur *cur,
xfs_agblock_t bno,
int *stat)
{
trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_private.a.agno, bno,
XFS_LOOKUP_GE);
cur->bc_rec.rc.rc_startblock = bno;
cur->bc_rec.rc.rc_blockcount = 0;
return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
}
/*
* Get the data from the pointed-to record.
*/
int
xfs_refcount_get_rec(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *irec,
int *stat)
{
union xfs_btree_rec *rec;
int error;
error = xfs_btree_get_rec(cur, &rec, stat);
if (!error && *stat == 1) {
irec->rc_startblock = be32_to_cpu(rec->refc.rc_startblock);
irec->rc_blockcount = be32_to_cpu(rec->refc.rc_blockcount);
irec->rc_refcount = be32_to_cpu(rec->refc.rc_refcount);
trace_xfs_refcount_get(cur->bc_mp, cur->bc_private.a.agno,
irec);
}
return error;
}
/*
* Update the record referred to by cur to the value given
* by [bno, len, refcount].
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
STATIC int
xfs_refcount_update(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *irec)
{
union xfs_btree_rec rec;
int error;
trace_xfs_refcount_update(cur->bc_mp, cur->bc_private.a.agno, irec);
rec.refc.rc_startblock = cpu_to_be32(irec->rc_startblock);
rec.refc.rc_blockcount = cpu_to_be32(irec->rc_blockcount);
rec.refc.rc_refcount = cpu_to_be32(irec->rc_refcount);
error = xfs_btree_update(cur, &rec);
if (error)
trace_xfs_refcount_update_error(cur->bc_mp,
cur->bc_private.a.agno, error, _RET_IP_);
return error;
}
/*
* Insert the record referred to by cur to the value given
* by [bno, len, refcount].
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
STATIC int
xfs_refcount_insert(
struct xfs_btree_cur *cur,
struct xfs_refcount_irec *irec,
int *i)
{
int error;
trace_xfs_refcount_insert(cur->bc_mp, cur->bc_private.a.agno, irec);
cur->bc_rec.rc.rc_startblock = irec->rc_startblock;
cur->bc_rec.rc.rc_blockcount = irec->rc_blockcount;
cur->bc_rec.rc.rc_refcount = irec->rc_refcount;
error = xfs_btree_insert(cur, i);
XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, *i == 1, out_error);
out_error:
if (error)
trace_xfs_refcount_insert_error(cur->bc_mp,
cur->bc_private.a.agno, error, _RET_IP_);
return error;
}
/*
* Remove the record referred to by cur, then set the pointer to the spot
* where the record could be re-inserted, in case we want to increment or
* decrement the cursor.
* This either works (return 0) or gets an EFSCORRUPTED error.
*/
STATIC int
xfs_refcount_delete(
struct xfs_btree_cur *cur,
int *i)
{
struct xfs_refcount_irec irec;
int found_rec;
int error;
error = xfs_refcount_get_rec(cur, &irec, &found_rec);
if (error)
goto out_error;
XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error);
trace_xfs_refcount_delete(cur->bc_mp, cur->bc_private.a.agno, &irec);
error = xfs_btree_delete(cur, i);
XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, *i == 1, out_error);
if (error)
goto out_error;
error = xfs_refcount_lookup_ge(cur, irec.rc_startblock, &found_rec);
out_error:
if (error)
trace_xfs_refcount_delete_error(cur->bc_mp,
cur->bc_private.a.agno, error, _RET_IP_);
return error;
}