1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (c) 1999 Al Smith
4 *
5 * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
6 * Portions derived from IRIX header files (c) 1988 Silicon Graphics
7 */
8 #ifndef _EFS_EFS_H_
9 #define _EFS_EFS_H_
10
11 #ifdef pr_fmt
12 #undef pr_fmt
13 #endif
14
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17 #include <linux/fs.h>
18 #include <linux/uaccess.h>
19
20 #define EFS_VERSION "1.0a"
21
22 static const char cprt[] = "EFS: "EFS_VERSION" - (c) 1999 Al Smith <Al.Smith@aeschi.ch.eu.org>";
23
24
25 /* 1 block is 512 bytes */
26 #define EFS_BLOCKSIZE_BITS 9
27 #define EFS_BLOCKSIZE (1 << EFS_BLOCKSIZE_BITS)
28
29 typedef int32_t efs_block_t;
30 typedef uint32_t efs_ino_t;
31
32 #define EFS_DIRECTEXTENTS 12
33
34 /*
35 * layout of an extent, in memory and on disk. 8 bytes exactly.
36 */
37 typedef union extent_u {
38 unsigned char raw[8];
39 struct extent_s {
40 unsigned int ex_magic:8; /* magic # (zero) */
41 unsigned int ex_bn:24; /* basic block */
42 unsigned int ex_length:8; /* numblocks in this extent */
43 unsigned int ex_offset:24; /* logical offset into file */
44 } cooked;
45 } efs_extent;
46
47 typedef struct edevs {
48 __be16 odev;
49 __be32 ndev;
50 } efs_devs;
51
52 /*
53 * extent based filesystem inode as it appears on disk. The efs inode
54 * is exactly 128 bytes long.
55 */
56 struct efs_dinode {
57 __be16 di_mode; /* mode and type of file */
58 __be16 di_nlink; /* number of links to file */
59 __be16 di_uid; /* owner's user id */
60 __be16 di_gid; /* owner's group id */
61 __be32 di_size; /* number of bytes in file */
62 __be32 di_atime; /* time last accessed */
63 __be32 di_mtime; /* time last modified */
64 __be32 di_ctime; /* time created */
65 __be32 di_gen; /* generation number */
66 __be16 di_numextents; /* # of extents */
67 u_char di_version; /* version of inode */
68 u_char di_spare; /* spare - used by AFS */
69 union di_addr {
70 efs_extent di_extents[EFS_DIRECTEXTENTS];
71 efs_devs di_dev; /* device for IFCHR/IFBLK */
72 } di_u;
73 };
74
75 /* efs inode storage in memory */
76 struct efs_inode_info {
77 int numextents;
78 int lastextent;
79
80 efs_extent extents[EFS_DIRECTEXTENTS];
81 struct inode vfs_inode;
82 };
83
84 #include <linux/efs_fs_sb.h>
85
86 #define EFS_DIRBSIZE_BITS EFS_BLOCKSIZE_BITS
87 #define EFS_DIRBSIZE (1 << EFS_DIRBSIZE_BITS)
88
89 struct efs_dentry {
90 __be32 inode;
91 unsigned char namelen;
92 char name[3];
93 };
94
95 #define EFS_DENTSIZE (sizeof(struct efs_dentry) - 3 + 1)
96 #define EFS_MAXNAMELEN ((1 << (sizeof(char) * 8)) - 1)
97
98 #define EFS_DIRBLK_HEADERSIZE 4
99 #define EFS_DIRBLK_MAGIC 0xbeef /* moo */
100
101 struct efs_dir {
102 __be16 magic;
103 unsigned char firstused;
104 unsigned char slots;
105
106 unsigned char space[EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE];
107 };
108
109 #define EFS_MAXENTS \
110 ((EFS_DIRBSIZE - EFS_DIRBLK_HEADERSIZE) / \
111 (EFS_DENTSIZE + sizeof(char)))
112
113 #define EFS_SLOTAT(dir, slot) EFS_REALOFF((dir)->space[slot])
114
115 #define EFS_REALOFF(offset) ((offset << 1))
116
117
INODE_INFO(struct inode * inode)118 static inline struct efs_inode_info *INODE_INFO(struct inode *inode)
119 {
120 return container_of(inode, struct efs_inode_info, vfs_inode);
121 }
122
SUPER_INFO(struct super_block * sb)123 static inline struct efs_sb_info *SUPER_INFO(struct super_block *sb)
124 {
125 return sb->s_fs_info;
126 }
127
128 struct statfs;
129 struct fid;
130
131 extern const struct inode_operations efs_dir_inode_operations;
132 extern const struct file_operations efs_dir_operations;
133 extern const struct address_space_operations efs_symlink_aops;
134
135 extern struct inode *efs_iget(struct super_block *, unsigned long);
136 extern efs_block_t efs_map_block(struct inode *, efs_block_t);
137 extern int efs_get_block(struct inode *, sector_t, struct buffer_head *, int);
138
139 extern struct dentry *efs_lookup(struct inode *, struct dentry *, unsigned int);
140 extern struct dentry *efs_fh_to_dentry(struct super_block *sb, struct fid *fid,
141 int fh_len, int fh_type);
142 extern struct dentry *efs_fh_to_parent(struct super_block *sb, struct fid *fid,
143 int fh_len, int fh_type);
144 extern struct dentry *efs_get_parent(struct dentry *);
145 extern int efs_bmap(struct inode *, int);
146
147 #endif /* _EFS_EFS_H_ */
148