1/*-
2 * Copyright (c) 2012, 2010 Zheng Liu <lz@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/fs/ext2fs/ext2_extents.h 262623 2014-02-28 21:25:32Z pfg $
27 */
28#ifndef _FS_EXT2FS_EXT2_EXTENTS_H_
29#define _FS_EXT2FS_EXT2_EXTENTS_H_
30
31#include <sys/types.h>
32
33#define EXT4_EXT_MAGIC 0xf30a
34
35#define EXT4_EXT_CACHE_NO 0
36#define EXT4_EXT_CACHE_GAP 1
37#define EXT4_EXT_CACHE_IN 2
38
39/*
40 * Ext4 file system extent on disk.
41 */
42struct ext4_extent {
43 uint32_t e_blk; /* first logical block */
44 uint16_t e_len; /* number of blocks */
45 uint16_t e_start_hi; /* high 16 bits of physical block */
46 uint32_t e_start_lo; /* low 32 bits of physical block */
47};
48
49/*
50 * Extent index on disk.
51 */
52struct ext4_extent_index {
53 uint32_t ei_blk; /* indexes logical blocks */
54 uint32_t ei_leaf_lo; /* points to physical block of the
55 * next level */
56 uint16_t ei_leaf_hi; /* high 16 bits of physical block */
57 uint16_t ei_unused;
58};
59
60/*
61 * Extent tree header.
62 */
63struct ext4_extent_header {
64 uint16_t eh_magic; /* magic number: 0xf30a */
65 uint16_t eh_ecount; /* number of valid entries */
66 uint16_t eh_max; /* capacity of store in entries */
67 uint16_t eh_depth; /* the depth of extent tree */
68 uint32_t eh_gen; /* generation of extent tree */
69};
70
71/*
72 * Save cached extent.
73 */
74struct ext4_extent_cache {
75 daddr_t ec_start; /* extent start */
76 uint32_t ec_blk; /* logical block */
77 uint32_t ec_len;
78 uint32_t ec_type;
79};
80
81/*
82 * Save path to some extent.
83 */
84struct ext4_extent_path {
85 uint16_t ep_depth;
86 struct buf *ep_bp;
87 struct ext4_extent *ep_ext;
88 struct ext4_extent_index *ep_index;
89 struct ext4_extent_header *ep_header;
90};
91
92struct inode;
93struct m_ext2fs;
94int ext4_ext_in_cache(struct inode *, daddr_t, struct ext4_extent *);
95void ext4_ext_put_cache(struct inode *, struct ext4_extent *, int);
96struct ext4_extent_path *ext4_ext_find_extent(struct m_ext2fs *fs,
97 struct inode *, daddr_t, struct ext4_extent_path *);
98
99#endif /* !_FS_EXT2FS_EXT2_EXTENTS_H_ */