xref: /openbmc/linux/fs/nilfs2/direct.h (revision a09d2831)
1 /*
2  * direct.h - NILFS direct block pointer.
3  *
4  * Copyright (C) 2006-2008 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 Koji Sato <koji@osrg.net>.
21  */
22 
23 #ifndef _NILFS_DIRECT_H
24 #define _NILFS_DIRECT_H
25 
26 #include <linux/types.h>
27 #include <linux/buffer_head.h>
28 #include "bmap.h"
29 
30 
31 struct nilfs_direct;
32 
33 /**
34  * struct nilfs_direct_node - direct node
35  * @dn_flags: flags
36  * @dn_pad: padding
37  */
38 struct nilfs_direct_node {
39 	__u8 dn_flags;
40 	__u8 pad[7];
41 };
42 
43 /**
44  * struct nilfs_direct - direct mapping
45  * @d_bmap: bmap structure
46  */
47 struct nilfs_direct {
48 	struct nilfs_bmap d_bmap;
49 };
50 
51 
52 #define NILFS_DIRECT_NBLOCKS	(NILFS_BMAP_SIZE / sizeof(__le64) - 1)
53 #define NILFS_DIRECT_KEY_MIN	0
54 #define NILFS_DIRECT_KEY_MAX	(NILFS_DIRECT_NBLOCKS - 1)
55 
56 
57 int nilfs_direct_init(struct nilfs_bmap *);
58 int nilfs_direct_delete_and_convert(struct nilfs_bmap *, __u64, __u64 *,
59 				    __u64 *, int);
60 
61 
62 #endif	/* _NILFS_DIRECT_H */
63