1/*	$NetBSD: ext2fs_extents.h,v 1.5 2023/08/26 05:22:50 riastradh Exp $	*/
2
3/*-
4 * Copyright (c) 2012, 2010 Zheng Liu <lz@freebsd.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: head/sys/fs/ext2fs/ext2_extents.h 295523 2016-02-11 15:27:14Z pfg $
29 */
30
31#ifndef _UFS_EXT2FS_EXT2FS_EXTENTS_H_
32#define	_UFS_EXT2FS_EXT2FS_EXTENTS_H_
33
34#include <sys/types.h>
35#ifndef _KERNEL
36#include <stdbool.h>
37#endif
38
39#include <ufs/ufs/inode.h>
40#define	EXT4_EXT_MAGIC  0xf30a
41
42#define	EXT4_EXT_CACHE_NO	0
43#define	EXT4_EXT_CACHE_GAP	1
44#define	EXT4_EXT_CACHE_IN	2
45
46/*
47 * Ext4 file system extent on disk.
48 */
49struct ext4_extent {
50	uint32_t e_blk;		/* first logical block */
51	uint16_t e_len;		/* number of blocks */
52	uint16_t e_start_hi;	/* high 16 bits of physical block */
53	uint32_t e_start_lo;	/* low 32 bits of physical block */
54};
55
56/*
57 * Extent index on disk.
58 */
59struct ext4_extent_index {
60	uint32_t ei_blk;	/* indexes logical blocks */
61	uint32_t ei_leaf_lo;	/* points to physical block of the
62				 * next level */
63	uint16_t ei_leaf_hi;	/* high 16 bits of physical block */
64	uint16_t ei_unused;
65};
66
67/*
68 * Extent tree header.
69 */
70struct ext4_extent_header {
71	uint16_t eh_magic;	/* magic number: 0xf30a */
72	uint16_t eh_ecount;	/* number of valid entries */
73	uint16_t eh_max;	/* capacity of store in entries */
74	uint16_t eh_depth;	/* the depth of extent tree */
75	uint32_t eh_gen;	/* generation of extent tree */
76};
77
78/*
79 * Save cached extent.
80 */
81struct ext4_extent_cache {
82	daddr_t	ec_start;	/* extent start */
83	uint32_t ec_blk;	/* logical block */
84	uint32_t ec_len;
85	uint32_t ec_type;
86};
87
88/*
89 * Save path to some extent.
90 */
91struct ext4_extent_path {
92	uint16_t ep_depth;
93	struct buf *ep_bp;
94	bool ep_is_sparse;
95	union {
96		struct ext4_extent ep_sparse_ext;
97		struct ext4_extent *ep_ext;
98	};
99	struct ext4_extent_index *ep_index;
100	struct ext4_extent_header *ep_header;
101};
102
103struct inode;
104struct m_ext2fs;
105
106int	ext4_ext_in_cache(struct inode *, daddr_t, struct ext4_extent *);
107void	ext4_ext_put_cache(struct inode *, struct ext4_extent *, int);
108struct ext4_extent_path *ext4_ext_find_extent(struct m_ext2fs *fs,
109    struct inode *, daddr_t, struct ext4_extent_path *);
110
111#endif /* !_UFS_EXT2FS_EXT2FS_EXTENTS_H_ */
112