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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
|
#ifndef _LINUX_SYSV_FS_H
#define _LINUX_SYSV_FS_H
/*
* The SystemV/Coherent filesystem constants/structures/macros
*/
/* This code assumes
- a little endian processor like 386,
- sizeof(short) = 2, sizeof(int) = 4, sizeof(long) = 4,
- alignof(short) = 2, alignof(long) = 4.
*/
#ifdef __GNUC__
#define __packed2__ __attribute__ ((packed, aligned(2)))
#else
#error I want gcc!
#endif
#include <linux/stat.h> /* declares S_IFLNK etc. */
#include <linux/sched.h> /* declares wake_up() */
#include <linux/sysv_fs_sb.h> /* defines the sv_... shortcuts */
/* Layout on disk */
/* ============== */
/* The block size is sb->sv_block_size which may be smaller than BLOCK_SIZE. */
/* zones (= data allocation units) are blocks */
/* On Coherent FS, 32 bit quantities are stored using (I quote the Coherent
manual) a "canonical byte ordering". This is the PDP-11 byte ordering:
x = 2^24 * byte3 + 2^16 * byte2 + 2^8 * byte1 + byte0 is stored
as { byte2, byte3, byte0, byte1 }. We need conversions.
*/
typedef unsigned long coh_ulong;
static inline coh_ulong to_coh_ulong (unsigned long x)
{
return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16);
}
static inline unsigned long from_coh_ulong (coh_ulong x)
{
return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16);
}
/* inode numbers are 16 bit */
typedef unsigned short sysv_ino_t;
/* Block numbers are 24 bit, sometimes stored in 32 bit.
On Coherent FS, they are always stored in PDP-11 manner: the least
significant 16 bits come last.
*/
typedef unsigned long sysv_zone_t;
/* Among the blocks ... */
/* Xenix FS, Coherent FS: block 0 is the boot block, block 1 the super-block.
SystemV FS: block 0 contains both the boot sector and the super-block. */
/* The first inode zone is sb->sv_firstinodezone (1 or 2). */
/* Among the inodes ... */
/* 0 is non-existent */
#define SYSV_BADBL_INO 1 /* inode of bad blocks file */
#define SYSV_ROOT_INO 2 /* inode of root directory */
/* Xenix super-block data on disk */
#define XENIX_NICINOD 100 /* number of inode cache entries */
#define XENIX_NICFREE 100 /* number of free block list chunk entries */
struct xenix_super_block {
unsigned short s_isize; /* index of first data zone */
unsigned long s_fsize __packed2__; /* total number of zones of this fs */
/* the start of the free block list: */
unsigned short s_nfree; /* number of free blocks in s_free, <= XENIX_NICFREE */
unsigned long s_free[XENIX_NICFREE]; /* first free block list chunk */
/* the cache of free inodes: */
unsigned short s_ninode; /* number of free inodes in s_inode, <= XENIX_NICINOD */
sysv_ino_t s_inode[XENIX_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
unsigned long s_time __packed2__; /* time of last super block update */
unsigned long s_tfree __packed2__; /* total number of free zones */
unsigned short s_tinode; /* total number of free inodes */
short s_dinfo[4]; /* device information ?? */
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
char s_clean; /* set to 0x46 when filesystem is properly unmounted */
char s_fill[371];
long s_magic; /* version of file system */
long s_type; /* type of file system: 1 for 512 byte blocks
2 for 1024 byte blocks */
};
/* Xenix free list block on disk */
struct xenix_freelist_chunk {
unsigned short fl_nfree; /* number of free blocks in fl_free, <= XENIX_NICFREE] */
unsigned long fl_free[XENIX_NICFREE] __packed2__;
};
/* SystemV FS comes in two variants:
* sysv2: System V Release 2 (e.g. Microport), structure elements aligned(2).
* sysv4: System V Release 4 (e.g. Consensys), structure elements aligned(4).
*/
#define SYSV_NICINOD 100 /* number of inode cache entries */
#define SYSV_NICFREE 50 /* number of free block list chunk entries */
/* SystemV4 super-block data on disk */
struct sysv4_super_block {
unsigned short s_isize; /* index of first data zone */
unsigned long s_fsize; /* total number of zones of this fs */
/* the start of the free block list: */
unsigned short s_nfree; /* number of free blocks in s_free, <= SYSV_NICFREE */
unsigned long s_free[SYSV_NICFREE]; /* first free block list chunk */
/* the cache of free inodes: */
unsigned short s_ninode; /* number of free inodes in s_inode, <= SYSV_NICINOD */
sysv_ino_t s_inode[SYSV_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
unsigned long s_time; /* time of last super block update */
short s_dinfo[4]; /* device information ?? */
unsigned long s_tfree; /* total number of free zones */
unsigned short s_tinode; /* total number of free inodes */
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
long s_fill[12];
long s_state; /* file system state: 0x7c269d38-s_time means clean */
long s_magic; /* version of file system */
long s_type; /* type of file system: 1 for 512 byte blocks
2 for 1024 byte blocks */
};
/* SystemV4 free list block on disk */
struct sysv4_freelist_chunk {
unsigned short fl_nfree; /* number of free blocks in fl_free, <= SYSV_NICFREE] */
unsigned long fl_free[SYSV_NICFREE];
};
/* SystemV2 super-block data on disk */
struct sysv2_super_block {
unsigned short s_isize; /* index of first data zone */
unsigned long s_fsize __packed2__; /* total number of zones of this fs */
/* the start of the free block list: */
unsigned short s_nfree; /* number of free blocks in s_free, <= SYSV_NICFREE */
unsigned long s_free[SYSV_NICFREE]; /* first free block list chunk */
/* the cache of free inodes: */
unsigned short s_ninode; /* number of free inodes in s_inode, <= SYSV_NICINOD */
sysv_ino_t s_inode[SYSV_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
unsigned long s_time __packed2__; /* time of last super block update */
short s_dinfo[4]; /* device information ?? */
unsigned long s_tfree __packed2__; /* total number of free zones */
unsigned short s_tinode; /* total number of free inodes */
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
long s_fill[14];
long s_state; /* file system state: 0xcb096f43 means clean */
long s_magic; /* version of file system */
long s_type; /* type of file system: 1 for 512 byte blocks
2 for 1024 byte blocks */
};
/* SystemV2 free list block on disk */
struct sysv2_freelist_chunk {
unsigned short fl_nfree; /* number of free blocks in fl_free, <= SYSV_NICFREE] */
unsigned long fl_free[SYSV_NICFREE] __packed2__;
};
/* Coherent super-block data on disk */
#define COH_NICINOD 100 /* number of inode cache entries */
#define COH_NICFREE 64 /* number of free block list chunk entries */
struct coh_super_block {
unsigned short s_isize; /* index of first data zone */
coh_ulong s_fsize __packed2__; /* total number of zones of this fs */
/* the start of the free block list: */
unsigned short s_nfree; /* number of free blocks in s_free, <= COH_NICFREE */
coh_ulong s_free[COH_NICFREE] __packed2__; /* first free block list chunk */
/* the cache of free inodes: */
unsigned short s_ninode; /* number of free inodes in s_inode, <= COH_NICINOD */
sysv_ino_t s_inode[COH_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
coh_ulong s_time __packed2__; /* time of last super block update */
coh_ulong s_tfree __packed2__; /* total number of free zones */
unsigned short s_tinode; /* total number of free inodes */
unsigned short s_interleave_m; /* interleave factor */
unsigned short s_interleave_n;
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
unsigned long s_unique; /* zero, not used */
};
/* Coherent free list block on disk */
struct coh_freelist_chunk {
unsigned short fl_nfree; /* number of free blocks in fl_free, <= COH_NICFREE] */
unsigned long fl_free[COH_NICFREE] __packed2__;
};
/* SystemV/Coherent inode data on disk */
struct sysv_inode {
unsigned short i_mode;
unsigned short i_nlink;
unsigned short i_uid;
unsigned short i_gid;
unsigned long i_size;
union { /* directories, regular files, ... */
char i_addb[3*(10+1+1+1)+1]; /* zone numbers: max. 10 data blocks,
* then 1 indirection block,
* then 1 double indirection block,
* then 1 triple indirection block.
* Then maybe a "file generation number" ??
*/
/* devices */
dev_t i_rdev;
/* named pipes on Coherent */
struct {
char p_addp[30];
short p_pnc;
short p_prx;
short p_pwx;
} i_p;
} i_a;
unsigned long i_atime; /* time of last access */
unsigned long i_mtime; /* time of last modification */
unsigned long i_ctime; /* time of creation */
};
/* The admissible values for i_mode are listed in <linux/stat.h> :
* #define S_IFMT 00170000 mask for type
* #define S_IFREG 0100000 type = regular file
* #define S_IFBLK 0060000 type = block device
* #define S_IFDIR 0040000 type = directory
* #define S_IFCHR 0020000 type = character device
* #define S_IFIFO 0010000 type = named pipe
* #define S_ISUID 0004000 set user id
* #define S_ISGID 0002000 set group id
* #define S_ISVTX 0001000 save swapped text even after use
* Additionally for SystemV:
* #define S_IFLNK 0120000 type = symbolic link
* #define S_IFNAM 0050000 type = XENIX special named file ??
* Additionally for Coherent:
* #define S_IFMPB 0070000 type = multiplexed block device ??
* #define S_IFMPC 0030000 type = multiplexed character device ??
*
* Since Coherent doesn't know about symbolic links, we use a kludgey
* implementation of symbolic links: i_mode = COH_KLUDGE_SYMLINK_MODE
* denotes a symbolic link. When a regular file should get this mode by
* accident, it is automatically converted to COH_KLUDGE_NOT_SYMLINK.
* We use S_IFREG because only regular files (and Coherent pipes...) can have
* data blocks with arbitrary contents associated with them, and S_ISVTX
* ("save swapped text after use") because it is unused on both Linux and
* Coherent: Linux does much more intelligent paging, and Coherent hasn't
* virtual memory at all.
* Same trick for Xenix.
*/
#define COH_KLUDGE_SYMLINK_MODE (S_IFREG | S_ISVTX)
#define COH_KLUDGE_NOT_SYMLINK (S_IFREG | S_ISVTX | S_IRUSR) /* force read access */
extern inline mode_t from_coh_imode(unsigned short mode)
{
if (mode == COH_KLUDGE_SYMLINK_MODE)
return (S_IFLNK | 0777);
else
return mode;
}
extern inline unsigned short to_coh_imode(mode_t mode)
{
if (S_ISLNK(mode))
return COH_KLUDGE_SYMLINK_MODE;
else if (mode == COH_KLUDGE_SYMLINK_MODE)
return COH_KLUDGE_NOT_SYMLINK;
else
return mode;
}
/* Admissible values for i_nlink: 0.._LINK_MAX */
#define XENIX_LINK_MAX 126 /* ?? */
#define SYSV_LINK_MAX 126 /* 127? 251? */
#define COH_LINK_MAX 10000 /* max number of hard links to an inode */
/* The number of inodes per block is
sb->sv_inodes_per_block = block_size / sizeof(struct sysv_inode) */
/* The number of indirect pointers per block is
sb->sv_ind_per_block = block_size / sizeof(unsigned long) */
/* SystemV/Coherent directory entry on disk */
#define SYSV_NAMELEN 14 /* max size of name in struct sysv_dir_entry */
struct sysv_dir_entry {
sysv_ino_t inode;
char name[SYSV_NAMELEN]; /* up to 14 characters, the rest are zeroes */
};
#define SYSV_DIRSIZE sizeof(struct sysv_dir_entry) /* size of every directory entry */
/* Operations */
/* ========== */
/* identify the FS in memory */
#define FSTYPE_XENIX 1
#define FSTYPE_SYSV4 2
#define FSTYPE_SYSV2 3
#define FSTYPE_COH 4
#define SYSV_MAGIC_BASE 0x012FF7B3
#define XENIX_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_XENIX)
#define SYSV4_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV4)
#define SYSV2_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV2)
#define COH_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_COH)
#ifdef __KERNEL__
/* sv_get_hash_table(sb,dev,block) is equivalent to get_hash_table(dev,block,block_size) */
static inline struct buffer_head *
sv_get_hash_table (struct super_block *sb, kdev_t dev, unsigned int block)
{
return get_hash_table (dev, block + sb->sv_block_base, sb->sv_block_size);
}
/* sv_getblk(sb,dev,block) is equivalent to getblk(dev,block,block_size) */
static inline struct buffer_head *
sv_getblk (struct super_block *sb, kdev_t dev, unsigned int block)
{
return getblk (dev, block + sb->sv_block_base, sb->sv_block_size);
}
/* sv_bread(sb,dev,block) is equivalent to bread(dev,block,block_size) */
static inline struct buffer_head *
sv_bread (struct super_block *sb, kdev_t dev, unsigned int block)
{
return bread (dev, block + sb->sv_block_base, sb->sv_block_size);
}
/*
* Function prototypes
*/
extern int sysv_lookup(struct inode * dir,const char * name, int len,
struct inode ** result);
extern int sysv_create(struct inode * dir,const char * name, int len, int mode,
struct inode ** result);
extern int sysv_mkdir(struct inode * dir, const char * name, int len, int mode);
extern int sysv_rmdir(struct inode * dir, const char * name, int len);
extern int sysv_unlink(struct inode * dir, const char * name, int len);
extern int sysv_symlink(struct inode * inode, const char * name, int len,
const char * symname);
extern int sysv_link(struct inode * oldinode, struct inode * dir, const char * name, int len);
extern int sysv_mknod(struct inode * dir, const char * name, int len, int mode, int rdev);
extern int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
struct inode * new_dir, struct dentry * new_dentry);
extern struct inode * sysv_new_inode(const struct inode * dir);
extern void sysv_free_inode(struct inode * inode);
extern unsigned long sysv_count_free_inodes(struct super_block *sb);
extern int sysv_new_block(struct super_block * sb);
extern void sysv_free_block(struct super_block * sb, unsigned int block);
extern unsigned long sysv_count_free_blocks(struct super_block *sb);
extern int sysv_bmap(struct inode *,int);
extern struct buffer_head * sysv_getblk(struct inode *, unsigned int, int);
extern struct buffer_head * sysv_file_bread(struct inode *, int, int);
extern ssize_t sysv_file_read(struct file *, char *, size_t, loff_t *);
extern void sysv_truncate(struct inode *);
extern void sysv_put_super(struct super_block *);
extern struct super_block *sysv_read_super(struct super_block *,void *,int);
extern int init_sysv_fs(void);
extern void sysv_write_super(struct super_block *);
extern void sysv_read_inode(struct inode *);
extern int sysv_notify_change(struct inode *, struct iattr *);
extern void sysv_write_inode(struct inode *);
extern void sysv_put_inode(struct inode *);
extern int sysv_statfs(struct super_block *, struct statfs *, int);
extern int sysv_sync_inode(struct inode *);
extern int sysv_sync_file(struct file *, struct dentry *);
extern int sysv_mmap(struct file *, struct vm_area_struct *);
extern struct inode_operations sysv_file_inode_operations;
extern struct inode_operations sysv_file_inode_operations_with_bmap;
extern struct inode_operations sysv_dir_inode_operations;
extern struct inode_operations sysv_symlink_inode_operations;
#endif /* __KERNEL__ */
#endif
|
