blob: 45d2c5cda8120682e182c526afdecd4acb647aec [file] [log] [blame]
Koji Sato36a580e2009-04-06 19:01:25 -07001/*
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
31struct nilfs_direct;
32
33/**
34 * struct nilfs_direct_operations - direct mapping operation table
35 */
36struct nilfs_direct_operations {
37 __u64 (*dop_find_target)(const struct nilfs_direct *, __u64);
38 void (*dop_set_target)(struct nilfs_direct *, __u64, __u64);
39 int (*dop_propagate)(struct nilfs_direct *, struct buffer_head *);
40 int (*dop_assign)(struct nilfs_direct *, __u64, __u64,
41 struct buffer_head **, sector_t,
42 union nilfs_binfo *);
43};
44
45/**
46 * struct nilfs_direct_node - direct node
47 * @dn_flags: flags
48 * @dn_pad: padding
49 */
50struct nilfs_direct_node {
51 __u8 dn_flags;
52 __u8 pad[7];
53};
54
55/**
56 * struct nilfs_direct - direct mapping
57 * @d_bmap: bmap structure
58 * @d_ops: direct mapping operation table
59 */
60struct nilfs_direct {
61 struct nilfs_bmap d_bmap;
62
63 /* direct-mapping-specific members */
64 const struct nilfs_direct_operations *d_ops;
65};
66
67
68#define NILFS_DIRECT_NBLOCKS (NILFS_BMAP_SIZE / sizeof(__le64) - 1)
69#define NILFS_DIRECT_KEY_MIN 0
70#define NILFS_DIRECT_KEY_MAX (NILFS_DIRECT_NBLOCKS - 1)
71
72
73int nilfs_direct_init(struct nilfs_bmap *, __u64, __u64);
74int nilfs_direct_delete_and_convert(struct nilfs_bmap *, __u64, __u64 *,
75 __u64 *, int, __u64, __u64);
76
77
78#endif /* _NILFS_DIRECT_H */