1 /*
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/rbtree.h>
20 
21 /* data type for block offset of block group */
22 typedef int ext3_grpblk_t;
23 typedef int ext4_grpblk_t;
24 
25 /* data type for filesystem-wide blocks number */
26 typedef unsigned long long ext3_fsblk_t;
27 typedef unsigned long long ext4_fsblk_t;
28 
29 /* data type for file logical block number */
30 typedef __u32 ext3_lblk_t;
31 typedef __u32 ext4_lblk_t;
32 
33 /* data type for block group number */
34 typedef unsigned int ext3_group_t;
35 typedef unsigned int ext4_group_t;
36 
37 #define E3FSBLK "%lu"
38 
39 struct ext3_reserve_window {
40     ext3_fsblk_t	_rsv_start;	/* First byte reserved */
41     ext3_fsblk_t	_rsv_end;	/* Last byte reserved or 0 */
42 };
43 
44 struct ext3_reserve_window_node {
45     struct rb_node		rsv_node;
46     __u32			rsv_goal_size;
47     __u32			rsv_alloc_hit;
48     struct ext3_reserve_window	rsv_window;
49 };
50 
51 struct ext3_block_alloc_info {
52     /* information about reservation window */
53     struct ext3_reserve_window_node	rsv_window_node;
54     /*
55      * was i_next_alloc_block in ext3_inode_info
56      * is the logical (file-relative) number of the
57      * most-recently-allocated block in this file.
58      * We use this for detecting linearly ascending allocation requests.
59      */
60     __u32                   last_alloc_logical_block;
61     /*
62      * Was i_next_alloc_goal in ext3_inode_info
63      * is the *physical* companion to i_next_alloc_block.
64      * it the physical block number of the block which was most-recentl
65      * allocated to this file.  This give us the goal (target) for the next
66      * allocation when we detect linearly ascending requests.
67      */
68     ext3_fsblk_t		last_alloc_physical_block;
69 };
70 
71 #define rsv_start rsv_window._rsv_start
72 #define rsv_end rsv_window._rsv_end
73 
74 /*
75  * third extended file system inode data in memory
76  */
77 struct ext3_inode_info {
78     __le32	i_data[15];	/* unconverted */
79     __u32	i_flags;
80 #ifdef EXT3_FRAGMENTS
81     __u32	i_faddr;
82     __u8	i_frag_no;
83     __u8	i_frag_size;
84 #endif
85     ext3_fsblk_t	i_file_acl;
86     __u32	i_dir_acl;
87     __u32	i_dtime;
88 
89     /*
90      * i_block_group is the number of the block group which contains
91      * this file's inode.  Constant across the lifetime of the inode,
92      * it is ued for making block allocation decisions - we try to
93      * place a file's data blocks near its inode block, and new inodes
94      * near to their parent directory's inode.
95      */
96     __u32	i_block_group;
97     __u32	i_state;		/* Dynamic state flags for ext3 */
98 
99     /* block reservation info */
100     struct ext3_block_alloc_info *i_block_alloc_info;
101 
102     __u32	i_dir_start_lookup;
103 #ifdef CONFIG_EXT3_FS_XATTR
104     /*
105      * Extended attributes can be read independently of the main file
106      * data. Taking i_mutex even when reading would cause contention
107      * between readers of EAs and writers of regular file data, so
108      * instead we synchronize on xattr_sem when reading or changing
109      * EAs.
110      */
111     struct rw_semaphore xattr_sem;
112 #endif
113 #ifdef CONFIG_EXT3_FS_POSIX_ACL
114     struct posix_acl	*i_acl;
115     struct posix_acl	*i_default_acl;
116 #endif
117 
118     struct list_head i_orphan;	/* unlinked but open inodes */
119 
120     /*
121      * i_disksize keeps track of what the inode size is ON DISK, not
122      * in memory.  During truncate, i_size is set to the new size by
123      * the VFS prior to calling ext3_truncate(), but the filesystem won't
124      * set i_disksize to 0 until the truncate is actually under way.
125      *
126      * The intent is that i_disksize always represents the blocks which
127      * are used by this file.  This allows recovery to restart truncate
128      * on orphans if we crash during truncate.  We actually write i_disksize
129      * into the on-disk inode when writing inodes out, instead of i_size.
130      *
131      * The only time when i_disksize and i_size may be different is when
132      * a truncate is in progress.  The only things which change i_disksize
133      * are ext3_get_block (growth) and ext3_truncate (shrinkth).
134      */
135     loff_t	i_disksize;
136 
137     /* on-disk additional length */
138     __u16 i_extra_isize;
139 
140 #if 0
141     /*
142      * truncate_mutex is for serialising ext3_truncate() against
143      * ext3_getblock().  In the 2.4 ext2 design, great chunks of inode's
144      * data tree are chopped off during truncate. We can't do that in
145      * ext3 because whenever we perform intermediate commits during
146      * truncate, the inode and all the metadata blocks *must* be in a
147      * consistent state which allows truncation of the orphans to restart
148      * during recovery.  Hence we must fix the get_block-vs-truncate race
149      * by other means, so we have truncate_mutex.
150      */
151     struct mutex truncate_mutex;
152 #endif
153     struct inode vfs_inode;
154 };
155 
156 #endif	/* _LINUX_EXT3_FS_I */
157