aboutsummaryrefslogtreecommitdiff
path: root/include/linux/ext3_fs_i.h
blob: 2914f7b0715661218287e48517bc608e8e3d124c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
/*
 *  linux/include/linux/ext3_fs_i.h
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 *  from
 *
 *  linux/include/linux/minix_fs_i.h
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#ifndef _LINUX_EXT3_FS_I
#define _LINUX_EXT3_FS_I

#include <linux/rwsem.h>
#include <linux/rbtree.h>
#include <linux/seqlock.h>

struct ext3_reserve_window {
	__u32			_rsv_start;	/* First byte reserved */
	__u32			_rsv_end;	/* Last byte reserved or 0 */
};

struct ext3_reserve_window_node {
	struct rb_node	 	rsv_node;
	__u32			rsv_goal_size;
	__u32			rsv_alloc_hit;
	struct ext3_reserve_window	rsv_window;
};

struct ext3_block_alloc_info {
	/* information about reservation window */
	struct ext3_reserve_window_node	rsv_window_node;
	/*
	 * was i_next_alloc_block in ext3_inode_info
	 * is the logical (file-relative) number of the
	 * most-recently-allocated block in this file.
	 * We use this for detecting linearly ascending allocation requests.
	 */
	__u32                   last_alloc_logical_block;
	/*
	 * Was i_next_alloc_goal in ext3_inode_info
	 * is the *physical* companion to i_next_alloc_block.
	 * it the the physical block number of the block which was most-recentl
	 * allocated to this file.  This give us the goal (target) for the next
	 * allocation when we detect linearly ascending requests.
	 */
	__u32                   last_alloc_physical_block;
};

#define rsv_start rsv_window._rsv_start
#define rsv_end rsv_window._rsv_end

/*
 * third extended file system inode data in memory
 */
struct ext3_inode_info {
	__le32	i_data[15];	/* unconverted */
	__u32	i_flags;
#ifdef EXT3_FRAGMENTS
	__u32	i_faddr;
	__u8	i_frag_no;
	__u8	i_frag_size;
#endif
	__u32	i_file_acl;
	__u32	i_dir_acl;
	__u32	i_dtime;

	/*
	 * i_block_group is the number of the block group which contains
	 * this file's inode.  Constant across the lifetime of the inode,
	 * it is ued for making block allocation decisions - we try to
	 * place a file's data blocks near its inode block, and new inodes
	 * near to their parent directory's inode.
	 */
	__u32	i_block_group;
	__u32	i_state;		/* Dynamic state flags for ext3 */

	/* block reservation info */
	struct ext3_block_alloc_info *i_block_alloc_info;

	__u32	i_dir_start_lookup;
#ifdef CONFIG_EXT3_FS_XATTR
	/*
	 * Extended attributes can be read independently of the main file
	 * data. Taking i_sem even when reading would cause contention
	 * between readers of EAs and writers of regular file data, so
	 * instead we synchronize on xattr_sem when reading or changing
	 * EAs.
	 */
	struct rw_semaphore xattr_sem;
#endif
#ifdef CONFIG_EXT3_FS_POSIX_ACL
	struct posix_acl	*i_acl;
	struct posix_acl	*i_default_acl;
#endif

	struct list_head i_orphan;	/* unlinked but open inodes */

	/*
	 * i_disksize keeps track of what the inode size is ON DISK, not
	 * in memory.  During truncate, i_size is set to the new size by
	 * the VFS prior to calling ext3_truncate(), but the filesystem won't
	 * set i_disksize to 0 until the truncate is actually under way.
	 *
	 * The intent is that i_disksize always represents the blocks which
	 * are used by this file.  This allows recovery to restart truncate
	 * on orphans if we crash during truncate.  We actually write i_disksize
	 * into the on-disk inode when writing inodes out, instead of i_size.
	 *
	 * The only time when i_disksize and i_size may be different is when
	 * a truncate is in progress.  The only things which change i_disksize
	 * are ext3_get_block (growth) and ext3_truncate (shrinkth).
	 */
	loff_t	i_disksize;

	/* on-disk additional length */
	__u16 i_extra_isize;

	/*
	 * truncate_sem is for serialising ext3_truncate() against
	 * ext3_getblock().  In the 2.4 ext2 design, great chunks of inode's
	 * data tree are chopped off during truncate. We can't do that in
	 * ext3 because whenever we perform intermediate commits during
	 * truncate, the inode and all the metadata blocks *must* be in a
	 * consistent state which allows truncation of the orphans to restart
	 * during recovery.  Hence we must fix the get_block-vs-truncate race
	 * by other means, so we have truncate_sem.
	 */
	struct semaphore truncate_sem;
	struct inode vfs_inode;
};

#endif	/* _LINUX_EXT3_FS_I */