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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/include/linux/ext3_fs_i.h
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/include/linux/minix_fs_i.h
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 */
15
16#ifndef _LINUX_EXT3_FS_I
17#define _LINUX_EXT3_FS_I
18
19#include <linux/rwsem.h>
20#include <linux/rbtree.h>
21#include <linux/seqlock.h>
22
23struct ext3_reserve_window {
24 __u32 _rsv_start; /* First byte reserved */
25 __u32 _rsv_end; /* Last byte reserved or 0 */
26};
27
28struct ext3_reserve_window_node {
29 struct rb_node rsv_node;
30 __u32 rsv_goal_size;
31 __u32 rsv_alloc_hit;
32 struct ext3_reserve_window rsv_window;
33};
34
35struct ext3_block_alloc_info {
36 /* information about reservation window */
37 struct ext3_reserve_window_node rsv_window_node;
38 /*
39 * was i_next_alloc_block in ext3_inode_info
40 * is the logical (file-relative) number of the
41 * most-recently-allocated block in this file.
42 * We use this for detecting linearly ascending allocation requests.
43 */
44 __u32 last_alloc_logical_block;
45 /*
46 * Was i_next_alloc_goal in ext3_inode_info
47 * is the *physical* companion to i_next_alloc_block.
48 * it the the physical block number of the block which was most-recentl
49 * allocated to this file. This give us the goal (target) for the next
50 * allocation when we detect linearly ascending requests.
51 */
52 __u32 last_alloc_physical_block;
53};
54
55#define rsv_start rsv_window._rsv_start
56#define rsv_end rsv_window._rsv_end
57
58/*
59 * third extended file system inode data in memory
60 */
61struct ext3_inode_info {
62 __le32 i_data[15]; /* unconverted */
63 __u32 i_flags;
64#ifdef EXT3_FRAGMENTS
65 __u32 i_faddr;
66 __u8 i_frag_no;
67 __u8 i_frag_size;
68#endif
69 __u32 i_file_acl;
70 __u32 i_dir_acl;
71 __u32 i_dtime;
72
73 /*
74 * i_block_group is the number of the block group which contains
75 * this file's inode. Constant across the lifetime of the inode,
76 * it is ued for making block allocation decisions - we try to
77 * place a file's data blocks near its inode block, and new inodes
78 * near to their parent directory's inode.
79 */
80 __u32 i_block_group;
81 __u32 i_state; /* Dynamic state flags for ext3 */
82
83 /* block reservation info */
84 struct ext3_block_alloc_info *i_block_alloc_info;
85
86 __u32 i_dir_start_lookup;
87#ifdef CONFIG_EXT3_FS_XATTR
88 /*
89 * Extended attributes can be read independently of the main file
90 * data. Taking i_sem even when reading would cause contention
91 * between readers of EAs and writers of regular file data, so
92 * instead we synchronize on xattr_sem when reading or changing
93 * EAs.
94 */
95 struct rw_semaphore xattr_sem;
96#endif
97#ifdef CONFIG_EXT3_FS_POSIX_ACL
98 struct posix_acl *i_acl;
99 struct posix_acl *i_default_acl;
100#endif
101
102 struct list_head i_orphan; /* unlinked but open inodes */
103
104 /*
105 * i_disksize keeps track of what the inode size is ON DISK, not
106 * in memory. During truncate, i_size is set to the new size by
107 * the VFS prior to calling ext3_truncate(), but the filesystem won't
108 * set i_disksize to 0 until the truncate is actually under way.
109 *
110 * The intent is that i_disksize always represents the blocks which
111 * are used by this file. This allows recovery to restart truncate
112 * on orphans if we crash during truncate. We actually write i_disksize
113 * into the on-disk inode when writing inodes out, instead of i_size.
114 *
115 * The only time when i_disksize and i_size may be different is when
116 * a truncate is in progress. The only things which change i_disksize
117 * are ext3_get_block (growth) and ext3_truncate (shrinkth).
118 */
119 loff_t i_disksize;
120
121 /* on-disk additional length */
122 __u16 i_extra_isize;
123
124 /*
125 * truncate_sem is for serialising ext3_truncate() against
126 * ext3_getblock(). In the 2.4 ext2 design, great chunks of inode's
127 * data tree are chopped off during truncate. We can't do that in
128 * ext3 because whenever we perform intermediate commits during
129 * truncate, the inode and all the metadata blocks *must* be in a
130 * consistent state which allows truncation of the orphans to restart
131 * during recovery. Hence we must fix the get_block-vs-truncate race
132 * by other means, so we have truncate_sem.
133 */
134 struct semaphore truncate_sem;
135 struct inode vfs_inode;
136};
137
138#endif /* _LINUX_EXT3_FS_I */