alistair23-linux/fs/ocfs2/aops.h
Tao Ma 6f70fa5199 ocfs2: Add CoW support.
This patch try CoW support for a refcounted record.

the whole process will be:
1. Calculate how many clusters we need to CoW and where we start.
   Extents that are not completely encompassed by the write will
   be broken on 1MB boundaries.
2. Do CoW for the clusters with the help of page cache.
3. Change the b-tree structure with the new allocated clusters.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
2009-09-22 20:09:36 -07:00

78 lines
2.7 KiB
C

/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* Copyright (C) 2002, 2004, 2005 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_AOPS_H
#define OCFS2_AOPS_H
int ocfs2_prepare_write_nolock(struct inode *inode, struct page *page,
unsigned from, unsigned to);
handle_t *ocfs2_start_walk_page_trans(struct inode *inode,
struct page *page,
unsigned from,
unsigned to);
int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
struct inode *inode, unsigned int from,
unsigned int to, int new);
void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages);
int walk_page_buffers( handle_t *handle,
struct buffer_head *head,
unsigned from,
unsigned to,
int *partial,
int (*fn)( handle_t *handle,
struct buffer_head *bh));
int ocfs2_write_end_nolock(struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata);
int ocfs2_write_begin_nolock(struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata,
struct buffer_head *di_bh, struct page *mmap_page);
int ocfs2_read_inline_data(struct inode *inode, struct page *page,
struct buffer_head *di_bh);
int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size);
int ocfs2_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create);
/* all ocfs2_dio_end_io()'s fault */
#define ocfs2_iocb_is_rw_locked(iocb) \
test_bit(0, (unsigned long *)&iocb->private)
static inline void ocfs2_iocb_set_rw_locked(struct kiocb *iocb, int level)
{
set_bit(0, (unsigned long *)&iocb->private);
if (level)
set_bit(1, (unsigned long *)&iocb->private);
else
clear_bit(1, (unsigned long *)&iocb->private);
}
#define ocfs2_iocb_clear_rw_locked(iocb) \
clear_bit(0, (unsigned long *)&iocb->private)
#define ocfs2_iocb_rw_locked_level(iocb) \
test_bit(1, (unsigned long *)&iocb->private)
#endif /* OCFS2_FILE_H */