xref: /openbmc/linux/fs/nilfs2/page.h (revision 2fa5ebe3)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Buffer/page management specific to NILFS
4  *
5  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6  *
7  * Written by Ryusuke Konishi and Seiji Kihara.
8  */
9 
10 #ifndef _NILFS_PAGE_H
11 #define _NILFS_PAGE_H
12 
13 #include <linux/buffer_head.h>
14 #include "nilfs.h"
15 
16 /*
17  * Extended buffer state bits
18  */
19 enum {
20 	BH_NILFS_Allocated = BH_PrivateStart,
21 	BH_NILFS_Node,
22 	BH_NILFS_Volatile,
23 	BH_NILFS_Checked,
24 	BH_NILFS_Redirected,
25 };
26 
27 BUFFER_FNS(NILFS_Node, nilfs_node)		/* nilfs node buffers */
28 BUFFER_FNS(NILFS_Volatile, nilfs_volatile)
29 BUFFER_FNS(NILFS_Checked, nilfs_checked)	/* buffer is verified */
30 BUFFER_FNS(NILFS_Redirected, nilfs_redirected)	/* redirected to a copy */
31 
32 
33 int __nilfs_clear_page_dirty(struct page *);
34 
35 struct buffer_head *nilfs_grab_buffer(struct inode *, struct address_space *,
36 				      unsigned long, unsigned long);
37 void nilfs_forget_buffer(struct buffer_head *);
38 void nilfs_copy_buffer(struct buffer_head *, struct buffer_head *);
39 int nilfs_page_buffers_clean(struct page *);
40 void nilfs_page_bug(struct page *);
41 
42 int nilfs_copy_dirty_pages(struct address_space *, struct address_space *);
43 void nilfs_copy_back_pages(struct address_space *, struct address_space *);
44 void nilfs_clear_dirty_page(struct page *, bool);
45 void nilfs_clear_dirty_pages(struct address_space *, bool);
46 unsigned int nilfs_page_count_clean_buffers(struct page *, unsigned int,
47 					    unsigned int);
48 unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
49 					    sector_t start_blk,
50 					    sector_t *blkoff);
51 
52 #define NILFS_PAGE_BUG(page, m, a...) \
53 	do { nilfs_page_bug(page); BUG(); } while (0)
54 
55 static inline struct buffer_head *
56 nilfs_page_get_nth_block(struct page *page, unsigned int count)
57 {
58 	struct buffer_head *bh = page_buffers(page);
59 
60 	while (count-- > 0)
61 		bh = bh->b_this_page;
62 	get_bh(bh);
63 	return bh;
64 }
65 
66 #endif /* _NILFS_PAGE_H */
67