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 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>,
21 * Seiji Kihara <kihara@osrg.net>.
22 */
23
24 #ifndef _NILFS_PAGE_H
25 #define _NILFS_PAGE_H
26
27 #include <linux/buffer_head.h>
28 #include "nilfs.h"
29
30 /*
31 * Extended buffer state bits
32 */
33 enum {
34 BH_NILFS_Allocated = BH_PrivateStart,
35 BH_NILFS_Node,
36 BH_NILFS_Volatile,
37 BH_NILFS_Checked,
38 BH_NILFS_Redirected,
39 };
40
41 BUFFER_FNS(NILFS_Allocated, nilfs_allocated) /* nilfs private buffers */
42 BUFFER_FNS(NILFS_Node, nilfs_node) /* nilfs node buffers */
43 BUFFER_FNS(NILFS_Volatile, nilfs_volatile)
44 BUFFER_FNS(NILFS_Checked, nilfs_checked) /* buffer is verified */
45 BUFFER_FNS(NILFS_Redirected, nilfs_redirected) /* redirected to a copy */
46
47
48 void nilfs_mark_buffer_dirty(struct buffer_head *bh);
49 int __nilfs_clear_page_dirty(struct page *);
50
51 struct buffer_head *nilfs_grab_buffer(struct inode *, struct address_space *,
52 unsigned long, unsigned long);
53 void nilfs_forget_buffer(struct buffer_head *);
54 void nilfs_copy_buffer(struct buffer_head *, struct buffer_head *);
55 int nilfs_page_buffers_clean(struct page *);
56 void nilfs_page_bug(struct page *);
57 struct page *nilfs_alloc_private_page(struct block_device *, int,
58 unsigned long);
59 void nilfs_free_private_page(struct page *);
60
61 int nilfs_copy_dirty_pages(struct address_space *, struct address_space *);
62 void nilfs_copy_back_pages(struct address_space *, struct address_space *);
63 void nilfs_clear_dirty_pages(struct address_space *);
64 void nilfs_mapping_init(struct address_space *mapping,
65 struct backing_dev_info *bdi);
66 unsigned nilfs_page_count_clean_buffers(struct page *, unsigned, unsigned);
67 unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
68 sector_t start_blk,
69 sector_t *blkoff);
70
71 #define NILFS_PAGE_BUG(page, m, a...) \
72 do { nilfs_page_bug(page); BUG(); } while (0)
73
74 static inline struct buffer_head *
nilfs_page_get_nth_block(struct page * page,unsigned int count)75 nilfs_page_get_nth_block(struct page *page, unsigned int count)
76 {
77 struct buffer_head *bh = page_buffers(page);
78
79 while (count-- > 0)
80 bh = bh->b_this_page;
81 get_bh(bh);
82 return bh;
83 }
84
85 #endif /* _NILFS_PAGE_H */
86