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: stable/10/sys/fs/ext2fs/ext2_extents.h 317532 2017-04-27 23:14:01Z 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 *
97ext4_ext_find_extent(struct m_ext2fs *fs,
98    struct inode *, daddr_t, struct ext4_extent_path *);
99
100#endif	/* !_FS_EXT2FS_EXT2_EXTENTS_H_ */
101