/*
* page.h - buffer/page management specific to NILFS
*
* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Written by Ryusuke Konishi <ryusuke@osrg.net>,
* Seiji Kihara <kihara@osrg.net>.
*/
#ifndef _NILFS_PAGE_H
#define _NILFS_PAGE_H
#include <linux/buffer_head.h>
#include "nilfs.h"
/*
* Extended buffer state bits
*/
enum {
BH_NILFS_Allocated = BH_PrivateStart,
BH_NILFS_Node,
BH_NILFS_Volatile,
BH_NILFS_Checked,
BH_NILFS_Redirected,
};
BUFFER_FNS(NILFS_Node, nilfs_node) /* nilfs node buffers */
BUFFER_FNS(NILFS_Volatile, nilfs_volatile)
BUFFER_FNS(NILFS_Checked, nilfs_checked) /* buffer is verified */
BUFFER_FNS(NILFS_Redirected, nilfs_redirected) /* redirected to a copy */
int __nilfs_clear_page_dirty(struct page *);
struct buffer_head *nilfs_grab_buffer(struct inode *, struct address_space *,
unsigned long, unsigned long);
void nilfs_forget_buffer(struct buffer_head *);
void nilfs_copy_buffer(struct buffer_head *, struct buffer_head *);
int nilfs_page_buffers_clean(struct page *);
void nilfs_page_bug(struct page *);
int nilfs_copy_dirty_pages(struct address_space *, struct address_space *);
void nilfs_copy_back_pages(struct address_space *, struct address_space *);
void nilfs_clear_dirty_pages(struct address_space *);
void nilfs_mapping_init(struct address_space *mapping, struct inode *inode,
struct backing_dev_info *bdi);
unsigned nilfs_page_count_clean_buffers(struct page *, unsigned, unsigned);
unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
sector_t start_blk,
sector_t *blkoff);
#define NILFS_PAGE_BUG(page, m, a...) \
do { nilfs_page_bug(page); BUG(); } while (0)
static inline struct buffer_head *
nilfs_page_get_nth_block(struct page *page, unsigned int count)
{
struct buffer_head *bh = page_buffers(page);
while (count-- > 0)
bh = bh->b_this_page;
get_bh(bh);
return bh;
}
#endif /* _NILFS_PAGE_H */
