1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_SYSV_FS_H
3#define _LINUX_SYSV_FS_H
4
5#define __packed2__ __attribute__((packed, aligned(2)))
6
7
8#ifndef __KERNEL__
9typedef u16 __fs16;
10typedef u32 __fs16;
11#endif
12
13/* inode numbers are 16 bit */
14typedef __fs16 sysv_ino_t;
15
16/* Block numbers are 24 bit, sometimes stored in 32 bit.
17 On Coherent FS, they are always stored in PDP-11 manner: the least
18 significant 16 bits come last. */
19typedef __fs32 sysv_zone_t;
20
21/* 0 is non-existent */
22#define SYSV_BADBL_INO 1 /* inode of bad blocks file */
23#define SYSV_ROOT_INO 2 /* inode of root directory */
24
25
26/* Xenix super-block data on disk */
27#define XENIX_NICINOD 100 /* number of inode cache entries */
28#define XENIX_NICFREE 100 /* number of free block list chunk entries */
29struct xenix_super_block {
30 __fs16 s_isize; /* index of first data zone */
31 __fs32 s_fsize __packed2__; /* total number of zones of this fs */
32 /* the start of the free block list: */
33 __fs16 s_nfree; /* number of free blocks in s_free, <= XENIX_NICFREE */
34 sysv_zone_t s_free[XENIX_NICFREE]; /* first free block list chunk */
35 /* the cache of free inodes: */
36 __fs16 s_ninode; /* number of free inodes in s_inode, <= XENIX_NICINOD */
37 sysv_ino_t s_inode[XENIX_NICINOD]; /* some free inodes */
38 /* locks, not used by Linux: */
39 char s_flock; /* lock during free block list manipulation */
40 char s_ilock; /* lock during inode cache manipulation */
41 char s_fmod; /* super-block modified flag */
42 char s_ronly; /* flag whether fs is mounted read-only */
43 __fs32 s_time __packed2__; /* time of last super block update */
44 __fs32 s_tfree __packed2__; /* total number of free zones */
45 __fs16 s_tinode; /* total number of free inodes */
46 __fs16 s_dinfo[4]; /* device information ?? */
47 char s_fname[6]; /* file system volume name */
48 char s_fpack[6]; /* file system pack name */
49 char s_clean; /* set to 0x46 when filesystem is properly unmounted */
50 char s_fill[371];
51 s32 s_magic; /* version of file system */
52 __fs32 s_type; /* type of file system: 1 for 512 byte blocks
53 2 for 1024 byte blocks
54 3 for 2048 byte blocks */
55
56};
57
58/*
59 * SystemV FS comes in two variants:
60 * sysv2: System V Release 2 (e.g. Microport), structure elements aligned(2).
61 * sysv4: System V Release 4 (e.g. Consensys), structure elements aligned(4).
62 */
63#define SYSV_NICINOD 100 /* number of inode cache entries */
64#define SYSV_NICFREE 50 /* number of free block list chunk entries */
65
66/* SystemV4 super-block data on disk */
67struct sysv4_super_block {
68 __fs16 s_isize; /* index of first data zone */
69 u16 s_pad0;
70 __fs32 s_fsize; /* total number of zones of this fs */
71 /* the start of the free block list: */
72 __fs16 s_nfree; /* number of free blocks in s_free, <= SYSV_NICFREE */
73 u16 s_pad1;
74 sysv_zone_t s_free[SYSV_NICFREE]; /* first free block list chunk */
75 /* the cache of free inodes: */
76 __fs16 s_ninode; /* number of free inodes in s_inode, <= SYSV_NICINOD */
77 u16 s_pad2;
78 sysv_ino_t s_inode[SYSV_NICINOD]; /* some free inodes */
79 /* locks, not used by Linux: */
80 char s_flock; /* lock during free block list manipulation */
81 char s_ilock; /* lock during inode cache manipulation */
82 char s_fmod; /* super-block modified flag */
83 char s_ronly; /* flag whether fs is mounted read-only */
84 __fs32 s_time; /* time of last super block update */
85 __fs16 s_dinfo[4]; /* device information ?? */
86 __fs32 s_tfree; /* total number of free zones */
87 __fs16 s_tinode; /* total number of free inodes */
88 u16 s_pad3;
89 char s_fname[6]; /* file system volume name */
90 char s_fpack[6]; /* file system pack name */
91 s32 s_fill[12];
92 __fs32 s_state; /* file system state: 0x7c269d38-s_time means clean */
93 s32 s_magic; /* version of file system */
94 __fs32 s_type; /* type of file system: 1 for 512 byte blocks
95 2 for 1024 byte blocks */
96};
97
98/* SystemV2 super-block data on disk */
99struct sysv2_super_block {
100 __fs16 s_isize; /* index of first data zone */
101 __fs32 s_fsize __packed2__; /* total number of zones of this fs */
102 /* the start of the free block list: */
103 __fs16 s_nfree; /* number of free blocks in s_free, <= SYSV_NICFREE */
104 sysv_zone_t s_free[SYSV_NICFREE]; /* first free block list chunk */
105 /* the cache of free inodes: */
106 __fs16 s_ninode; /* number of free inodes in s_inode, <= SYSV_NICINOD */
107 sysv_ino_t s_inode[SYSV_NICINOD]; /* some free inodes */
108 /* locks, not used by Linux: */
109 char s_flock; /* lock during free block list manipulation */
110 char s_ilock; /* lock during inode cache manipulation */
111 char s_fmod; /* super-block modified flag */
112 char s_ronly; /* flag whether fs is mounted read-only */
113 __fs32 s_time __packed2__; /* time of last super block update */
114 __fs16 s_dinfo[4]; /* device information ?? */
115 __fs32 s_tfree __packed2__; /* total number of free zones */
116 __fs16 s_tinode; /* total number of free inodes */
117 char s_fname[6]; /* file system volume name */
118 char s_fpack[6]; /* file system pack name */
119 s32 s_fill[14];
120 __fs32 s_state; /* file system state: 0xcb096f43 means clean */
121 s32 s_magic; /* version of file system */
122 __fs32 s_type; /* type of file system: 1 for 512 byte blocks
123 2 for 1024 byte blocks */
124};
125
126/* V7 super-block data on disk */
127#define V7_NICINOD 100 /* number of inode cache entries */
128#define V7_NICFREE 50 /* number of free block list chunk entries */
129struct v7_super_block {
130 __fs16 s_isize; /* index of first data zone */
131 __fs32 s_fsize __packed2__; /* total number of zones of this fs */
132 /* the start of the free block list: */
133 __fs16 s_nfree; /* number of free blocks in s_free, <= V7_NICFREE */
134 sysv_zone_t s_free[V7_NICFREE]; /* first free block list chunk */
135 /* the cache of free inodes: */
136 __fs16 s_ninode; /* number of free inodes in s_inode, <= V7_NICINOD */
137 sysv_ino_t s_inode[V7_NICINOD]; /* some free inodes */
138 /* locks, not used by Linux or V7: */
139 char s_flock; /* lock during free block list manipulation */
140 char s_ilock; /* lock during inode cache manipulation */
141 char s_fmod; /* super-block modified flag */
142 char s_ronly; /* flag whether fs is mounted read-only */
143 __fs32 s_time __packed2__; /* time of last super block update */
144 /* the following fields are not maintained by V7: */
145 __fs32 s_tfree __packed2__; /* total number of free zones */
146 __fs16 s_tinode; /* total number of free inodes */
147 __fs16 s_m; /* interleave factor */
148 __fs16 s_n; /* interleave factor */
149 char s_fname[6]; /* file system name */
150 char s_fpack[6]; /* file system pack name */
151};
152/* Constants to aid sanity checking */
153/* This is not a hard limit, nor enforced by v7 kernel. It's actually just
154 * the limit used by Seventh Edition's ls, though is high enough to assume
155 * that no reasonable file system would have that much entries in root
156 * directory. Thus, if we see anything higher, we just probably got the
157 * endiannes wrong. */
158#define V7_NFILES 1024
159/* The disk addresses are three-byte (despite direct block addresses being
160 * aligned word-wise in inode). If the most significant byte is non-zero,
161 * something is most likely wrong (not a filesystem, bad bytesex). */
162#define V7_MAXSIZE 0x00ffffff
163
164/* Coherent super-block data on disk */
165#define COH_NICINOD 100 /* number of inode cache entries */
166#define COH_NICFREE 64 /* number of free block list chunk entries */
167struct coh_super_block {
168 __fs16 s_isize; /* index of first data zone */
169 __fs32 s_fsize __packed2__; /* total number of zones of this fs */
170 /* the start of the free block list: */
171 __fs16 s_nfree; /* number of free blocks in s_free, <= COH_NICFREE */
172 sysv_zone_t s_free[COH_NICFREE] __packed2__; /* first free block list chunk */
173 /* the cache of free inodes: */
174 __fs16 s_ninode; /* number of free inodes in s_inode, <= COH_NICINOD */
175 sysv_ino_t s_inode[COH_NICINOD]; /* some free inodes */
176 /* locks, not used by Linux: */
177 char s_flock; /* lock during free block list manipulation */
178 char s_ilock; /* lock during inode cache manipulation */
179 char s_fmod; /* super-block modified flag */
180 char s_ronly; /* flag whether fs is mounted read-only */
181 __fs32 s_time __packed2__; /* time of last super block update */
182 __fs32 s_tfree __packed2__; /* total number of free zones */
183 __fs16 s_tinode; /* total number of free inodes */
184 __fs16 s_interleave_m; /* interleave factor */
185 __fs16 s_interleave_n;
186 char s_fname[6]; /* file system volume name */
187 char s_fpack[6]; /* file system pack name */
188 __fs32 s_unique; /* zero, not used */
189};
190
191/* SystemV/Coherent inode data on disk */
192struct sysv_inode {
193 __fs16 i_mode;
194 __fs16 i_nlink;
195 __fs16 i_uid;
196 __fs16 i_gid;
197 __fs32 i_size;
198 u8 i_data[3*(10+1+1+1)];
199 u8 i_gen;
200 __fs32 i_atime; /* time of last access */
201 __fs32 i_mtime; /* time of last modification */
202 __fs32 i_ctime; /* time of creation */
203};
204
205/* SystemV/Coherent directory entry on disk */
206#define SYSV_NAMELEN 14 /* max size of name in struct sysv_dir_entry */
207struct sysv_dir_entry {
208 sysv_ino_t inode;
209 char name[SYSV_NAMELEN]; /* up to 14 characters, the rest are zeroes */
210};
211
212#define SYSV_DIRSIZE sizeof(struct sysv_dir_entry) /* size of every directory entry */
213
214#endif /* _LINUX_SYSV_FS_H */
215

source code of linux/include/linux/sysv_fs.h