alistair23-linux/fs/ocfs2/buffer_head_io.h
Joel Becker d4a8c93c82 ocfs2: Make cached block reads the common case.
ocfs2_read_blocks() currently requires the CACHED flag for cached I/O.
However, that's the common case.  Let's flip it around and provide an
IGNORE_CACHE flag for the special users.  This has the added benefit of
cleaning up the code some (ignore_cache takes on its special meaning
earlier in the loop).

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-14 11:58:22 -07:00

73 lines
2.1 KiB
C

/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* ocfs2_buffer_head.h
*
* Buffer cache handling functions defined
*
* Copyright (C) 2002, 2004 Oracle. All rights reserved.
*
* 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 will 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 to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef OCFS2_BUFFER_HEAD_IO_H
#define OCFS2_BUFFER_HEAD_IO_H
#include <linux/buffer_head.h>
void ocfs2_end_buffer_io_sync(struct buffer_head *bh,
int uptodate);
static inline int ocfs2_read_block(struct inode *inode,
u64 off,
struct buffer_head **bh);
int ocfs2_write_block(struct ocfs2_super *osb,
struct buffer_head *bh,
struct inode *inode);
int ocfs2_read_blocks(struct inode *inode,
u64 block,
int nr,
struct buffer_head *bhs[],
int flags);
int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block,
unsigned int nr, struct buffer_head *bhs[]);
int ocfs2_write_super_or_backup(struct ocfs2_super *osb,
struct buffer_head *bh);
#define OCFS2_BH_IGNORE_CACHE 1
#define OCFS2_BH_READAHEAD 8
static inline int ocfs2_read_block(struct inode *inode, u64 off,
struct buffer_head **bh)
{
int status = 0;
if (bh == NULL) {
printk("ocfs2: bh == NULL\n");
status = -EINVAL;
goto bail;
}
status = ocfs2_read_blocks(inode, off, 1, bh, 0);
bail:
return status;
}
#endif /* OCFS2_BUFFER_HEAD_IO_H */