LXR linux/fs/nilfs2/page.h

   1/*
   2 * page.h - buffer/page management specific to NILFS
   3 *
   4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * Written by Ryusuke Konishi and Seiji Kihara.
  17 */
  18
  19#ifndef _NILFS_PAGE_H
  20#define _NILFS_PAGE_H
  21
  22#include <linux/buffer_head.h>
  23#include "nilfs.h"
  24
  25/*
  26 * Extended buffer state bits
  27 */
  28enum {
  29        BH_NILFS_Allocated = BH_PrivateStart,
  30        BH_NILFS_Node,
  31        BH_NILFS_Volatile,
  32        BH_NILFS_Checked,
  33        BH_NILFS_Redirected,
  34};
  35
  36BUFFER_FNS(NILFS_Node, nilfs_node)              /* nilfs node buffers */
  37BUFFER_FNS(NILFS_Volatile, nilfs_volatile)
  38BUFFER_FNS(NILFS_Checked, nilfs_checked)        /* buffer is verified */
  39BUFFER_FNS(NILFS_Redirected, nilfs_redirected)  /* redirected to a copy */
  40
  41
  42int __nilfs_clear_page_dirty(struct page *);
  43
  44struct buffer_head *nilfs_grab_buffer(struct inode *, struct address_space *,
  45                                      unsigned long, unsigned long);
  46void nilfs_forget_buffer(struct buffer_head *);
  47void nilfs_copy_buffer(struct buffer_head *, struct buffer_head *);
  48int nilfs_page_buffers_clean(struct page *);
  49void nilfs_page_bug(struct page *);
  50
  51int nilfs_copy_dirty_pages(struct address_space *, struct address_space *);
  52void nilfs_copy_back_pages(struct address_space *, struct address_space *);
  53void nilfs_clear_dirty_page(struct page *, bool);
  54void nilfs_clear_dirty_pages(struct address_space *, bool);
  55void nilfs_mapping_init(struct address_space *mapping, struct inode *inode);
  56unsigned int nilfs_page_count_clean_buffers(struct page *, unsigned int,
  57                                            unsigned int);
  58unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
  59                                            sector_t start_blk,
  60                                            sector_t *blkoff);
  61
  62#define NILFS_PAGE_BUG(page, m, a...) \
  63        do { nilfs_page_bug(page); BUG(); } while (0)
  64
  65static inline struct buffer_head *
  66nilfs_page_get_nth_block(struct page *page, unsigned int count)
  67{
  68        struct buffer_head *bh = page_buffers(page);
  69
  70        while (count-- > 0)
  71                bh = bh->b_this_page;
  72        get_bh(bh);
  73        return bh;
  74}
  75
  76#endif /* _NILFS_PAGE_H */
  77