xref: /freebsd/sys/fs/ext2fs/htree.h (revision 95ee2897e98f5d444f26ed2334cc7c439f9c16c6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2010, 2012 Zheng Liu <lz@freebsd.org>
5  * Copyright (c) 2012, Vyacheslav Matyushin
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef _FS_EXT2FS_HTREE_H_
31 #define	_FS_EXT2FS_HTREE_H_
32 
33 /* EXT3 HTree directory indexing */
34 
35 #define	EXT2_HTREE_LEGACY		0
36 #define	EXT2_HTREE_HALF_MD4		1
37 #define	EXT2_HTREE_TEA			2
38 #define	EXT2_HTREE_LEGACY_UNSIGNED	3
39 #define	EXT2_HTREE_HALF_MD4_UNSIGNED	4
40 #define	EXT2_HTREE_TEA_UNSIGNED		5
41 
42 #define	EXT2_HTREE_EOF 0x7FFFFFFF
43 
44 struct ext2fs_fake_direct {
45 	uint32_t e2d_ino;		/* inode number of entry */
46 	uint16_t e2d_reclen;		/* length of this record */
47 	uint8_t	e2d_namlen;		/* length of string in d_name */
48 	uint8_t	e2d_type;		/* file type */
49 };
50 
51 struct ext2fs_htree_count {
52 	uint16_t h_entries_max;
53 	uint16_t h_entries_num;
54 };
55 
56 struct ext2fs_htree_entry {
57 	uint32_t h_hash;
58 	uint32_t h_blk;
59 };
60 
61 /*
62  * This goes at the end of each htree block.
63  */
64 struct ext2fs_htree_tail {
65 	uint32_t ht_reserved;
66 	uint32_t ht_checksum;	/* crc32c(uuid+inum+dirblock) */
67 };
68 
69 struct ext2fs_htree_root_info {
70 	uint32_t h_reserved1;
71 	uint8_t	h_hash_version;
72 	uint8_t	h_info_len;
73 	uint8_t	h_ind_levels;
74 	uint8_t	h_reserved2;
75 };
76 
77 struct ext2fs_htree_root {
78 	struct ext2fs_fake_direct h_dot;
79 	char	h_dot_name[4];
80 	struct ext2fs_fake_direct h_dotdot;
81 	char	h_dotdot_name[4];
82 	struct ext2fs_htree_root_info h_info;
83 	struct ext2fs_htree_entry h_entries[0];
84 };
85 
86 struct ext2fs_htree_node {
87 	struct ext2fs_fake_direct h_fake_dirent;
88 	struct ext2fs_htree_entry h_entries[0];
89 };
90 
91 struct ext2fs_htree_lookup_level {
92 	struct buf *h_bp;
93 	struct ext2fs_htree_entry *h_entries;
94 	struct ext2fs_htree_entry *h_entry;
95 };
96 
97 struct ext2fs_htree_lookup_info {
98 	struct ext2fs_htree_lookup_level h_levels[2];
99 	uint32_t h_levels_num;
100 };
101 
102 struct ext2fs_htree_sort_entry {
103 	uint16_t h_offset;
104 	uint16_t h_size;
105 	uint32_t h_hash;
106 };
107 
108 #endif	/* !_FS_EXT2FS_HTREE_H_ */
109