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23#include <linux/module.h>
24
25#include <linux/fs.h>
26#include <linux/sysv_fs.h>
27#include <linux/init.h>
28
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31
32
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35
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40
41
42
43enum {
44 JAN_1_1980 = (10*365 + 2) * 24 * 60 * 60
45};
46
47static void detected_xenix(struct super_block *sb)
48{
49 struct buffer_head *bh1 = sb->sv_bh1;
50 struct buffer_head *bh2 = sb->sv_bh2;
51 struct xenix_super_block * sbd1;
52 struct xenix_super_block * sbd2;
53
54 if (bh1 != bh2)
55 sbd1 = sbd2 = (struct xenix_super_block *) bh1->b_data;
56 else {
57
58 sbd1 = (struct xenix_super_block *) bh1->b_data;
59 sbd2 = (struct xenix_super_block *) (bh2->b_data - 512);
60 }
61
62 sb->sv_link_max = XENIX_LINK_MAX;
63 sb->sv_fic_size = XENIX_NICINOD;
64 sb->sv_flc_size = XENIX_NICFREE;
65 sb->sv_sbd1 = (char *) sbd1;
66 sb->sv_sbd2 = (char *) sbd2;
67 sb->sv_sb_fic_count = &sbd1->s_ninode;
68 sb->sv_sb_fic_inodes = &sbd1->s_inode[0];
69 sb->sv_sb_total_free_inodes = &sbd2->s_tinode;
70 sb->sv_bcache_count = &sbd1->s_nfree;
71 sb->sv_bcache = &sbd1->s_free[0];
72 sb->sv_free_blocks = &sbd2->s_tfree;
73 sb->sv_sb_time = &sbd2->s_time;
74 sb->sv_firstdatazone = fs16_to_cpu(sb, sbd1->s_isize);
75 sb->sv_nzones = fs32_to_cpu(sb, sbd1->s_fsize);
76}
77
78static void detected_sysv4(struct super_block *sb)
79{
80 struct sysv4_super_block * sbd;
81 struct buffer_head *bh1 = sb->sv_bh1;
82 struct buffer_head *bh2 = sb->sv_bh2;
83
84 if (bh1 == bh2)
85 sbd = (struct sysv4_super_block *) (bh1->b_data + BLOCK_SIZE/2);
86 else
87 sbd = (struct sysv4_super_block *) bh2->b_data;
88
89 sb->sv_link_max = SYSV_LINK_MAX;
90 sb->sv_fic_size = SYSV_NICINOD;
91 sb->sv_flc_size = SYSV_NICFREE;
92 sb->sv_sbd1 = (char *) sbd;
93 sb->sv_sbd2 = (char *) sbd;
94 sb->sv_sb_fic_count = &sbd->s_ninode;
95 sb->sv_sb_fic_inodes = &sbd->s_inode[0];
96 sb->sv_sb_total_free_inodes = &sbd->s_tinode;
97 sb->sv_bcache_count = &sbd->s_nfree;
98 sb->sv_bcache = &sbd->s_free[0];
99 sb->sv_free_blocks = &sbd->s_tfree;
100 sb->sv_sb_time = &sbd->s_time;
101 sb->sv_sb_state = &sbd->s_state;
102 sb->sv_firstdatazone = fs16_to_cpu(sb, sbd->s_isize);
103 sb->sv_nzones = fs32_to_cpu(sb, sbd->s_fsize);
104}
105
106static void detected_sysv2(struct super_block *sb)
107{
108 struct sysv2_super_block * sbd;
109 struct buffer_head *bh1 = sb->sv_bh1;
110 struct buffer_head *bh2 = sb->sv_bh2;
111
112 if (bh1 == bh2)
113 sbd = (struct sysv2_super_block *) (bh1->b_data + BLOCK_SIZE/2);
114 else
115 sbd = (struct sysv2_super_block *) bh2->b_data;
116
117 sb->sv_link_max = SYSV_LINK_MAX;
118 sb->sv_fic_size = SYSV_NICINOD;
119 sb->sv_flc_size = SYSV_NICFREE;
120 sb->sv_sbd1 = (char *) sbd;
121 sb->sv_sbd2 = (char *) sbd;
122 sb->sv_sb_fic_count = &sbd->s_ninode;
123 sb->sv_sb_fic_inodes = &sbd->s_inode[0];
124 sb->sv_sb_total_free_inodes = &sbd->s_tinode;
125 sb->sv_bcache_count = &sbd->s_nfree;
126 sb->sv_bcache = &sbd->s_free[0];
127 sb->sv_free_blocks = &sbd->s_tfree;
128 sb->sv_sb_time = &sbd->s_time;
129 sb->sv_sb_state = &sbd->s_state;
130 sb->sv_firstdatazone = fs16_to_cpu(sb, sbd->s_isize);
131 sb->sv_nzones = fs32_to_cpu(sb, sbd->s_fsize);
132}
133
134static void detected_coherent(struct super_block *sb)
135{
136 struct coh_super_block * sbd;
137 struct buffer_head *bh1 = sb->sv_bh1;
138
139 sbd = (struct coh_super_block *) bh1->b_data;
140
141 sb->sv_link_max = COH_LINK_MAX;
142 sb->sv_fic_size = COH_NICINOD;
143 sb->sv_flc_size = COH_NICFREE;
144 sb->sv_sbd1 = (char *) sbd;
145 sb->sv_sbd2 = (char *) sbd;
146 sb->sv_sb_fic_count = &sbd->s_ninode;
147 sb->sv_sb_fic_inodes = &sbd->s_inode[0];
148 sb->sv_sb_total_free_inodes = &sbd->s_tinode;
149 sb->sv_bcache_count = &sbd->s_nfree;
150 sb->sv_bcache = &sbd->s_free[0];
151 sb->sv_free_blocks = &sbd->s_tfree;
152 sb->sv_sb_time = &sbd->s_time;
153 sb->sv_firstdatazone = fs16_to_cpu(sb, sbd->s_isize);
154 sb->sv_nzones = fs32_to_cpu(sb, sbd->s_fsize);
155}
156
157static void detected_v7(struct super_block *sb)
158{
159 struct buffer_head *bh2 = sb->sv_bh2;
160 struct v7_super_block *sbd = (struct v7_super_block *)bh2->b_data;
161
162 sb->sv_link_max = V7_LINK_MAX;
163 sb->sv_fic_size = V7_NICINOD;
164 sb->sv_flc_size = V7_NICFREE;
165 sb->sv_sbd1 = (char *)sbd;
166 sb->sv_sbd2 = (char *)sbd;
167 sb->sv_sb_fic_count = &sbd->s_ninode;
168 sb->sv_sb_fic_inodes = &sbd->s_inode[0];
169 sb->sv_sb_total_free_inodes = &sbd->s_tinode;
170 sb->sv_bcache_count = &sbd->s_nfree;
171 sb->sv_bcache = &sbd->s_free[0];
172 sb->sv_free_blocks = &sbd->s_tfree;
173 sb->sv_sb_time = &sbd->s_time;
174 sb->sv_firstdatazone = fs16_to_cpu(sb, sbd->s_isize);
175 sb->sv_nzones = fs32_to_cpu(sb, sbd->s_fsize);
176}
177
178static int detect_xenix (struct super_block *sb, struct buffer_head *bh)
179{
180 struct xenix_super_block * sbd = (struct xenix_super_block *)bh->b_data;
181 if (sbd->s_magic == cpu_to_le32(0x2b5544))
182 sb->sv_bytesex = BYTESEX_LE;
183 else if (sbd->s_magic == cpu_to_be32(0x2b5544))
184 sb->sv_bytesex = BYTESEX_BE;
185 else
186 return 0;
187 if (sbd->s_type > 2 || sbd->s_type < 1)
188 return 0;
189 sb->sv_type = FSTYPE_XENIX;
190 return sbd->s_type;
191}
192
193static int detect_sysv (struct super_block *sb, struct buffer_head *bh)
194{
195
196 struct sysv4_super_block * sbd;
197
198 sbd = (struct sysv4_super_block *) (bh->b_data + BLOCK_SIZE/2);
199 if (sbd->s_magic == cpu_to_le32(0xfd187e20))
200 sb->sv_bytesex = BYTESEX_LE;
201 else if (sbd->s_magic == cpu_to_be32(0xfd187e20))
202 sb->sv_bytesex = BYTESEX_BE;
203 else
204 return 0;
205
206 if (fs16_to_cpu(sb, sbd->s_nfree) == 0xffff) {
207 sb->sv_type = FSTYPE_AFS;
208 if (!(sb->s_flags & MS_RDONLY)) {
209 printk("SysV FS: SCO EAFS on %s detected, "
210 "forcing read-only mode.\n",
211 bdevname(sb->s_dev));
212 sb->s_flags |= MS_RDONLY;
213 }
214 return sbd->s_type;
215 }
216
217 if (fs32_to_cpu(sb, sbd->s_time) < JAN_1_1980) {
218
219 if (sbd->s_type > 3 || sbd->s_type < 1)
220 return 0;
221 sb->sv_type = FSTYPE_SYSV2;
222 return sbd->s_type;
223 }
224 if ((sbd->s_type > 3 || sbd->s_type < 1) &&
225 (sbd->s_type > 0x30 || sbd->s_type < 0x10))
226 return 0;
227
228
229
230
231
232
233 if (sbd->s_type >= 0x10) {
234 printk("SysV FS: can't handle long file names on %s, "
235 "forcing read-only mode.\n", kdevname(sb->s_dev));
236 sb->s_flags |= MS_RDONLY;
237 }
238
239 sb->sv_type = FSTYPE_SYSV4;
240 return sbd->s_type >= 0x10 ? (sbd->s_type >> 4) : sbd->s_type;
241}
242
243static int detect_coherent (struct super_block *sb, struct buffer_head *bh)
244{
245 struct coh_super_block * sbd;
246
247 sbd = (struct coh_super_block *) (bh->b_data + BLOCK_SIZE/2);
248 if ((memcmp(sbd->s_fname,"noname",6) && memcmp(sbd->s_fname,"xxxxx ",6))
249 || (memcmp(sbd->s_fpack,"nopack",6) && memcmp(sbd->s_fpack,"xxxxx\n",6)))
250 return 0;
251 sb->sv_bytesex = BYTESEX_PDP;
252 sb->sv_type = FSTYPE_COH;
253 return 1;
254}
255
256static int detect_sysv_odd(struct super_block *sb, struct buffer_head *bh)
257{
258 int size = detect_sysv(sb, bh);
259
260 return size>2 ? 0 : size;
261}
262
263static struct {
264 int block;
265 int (*test)(struct super_block *, struct buffer_head *);
266} flavours[] = {
267 {1, detect_xenix},
268 {0, detect_sysv},
269 {0, detect_coherent},
270 {9, detect_sysv_odd},
271 {15,detect_sysv_odd},
272 {18,detect_sysv},
273};
274
275static char *flavour_names[] = {
276 [FSTYPE_XENIX] "Xenix",
277 [FSTYPE_SYSV4] "SystemV",
278 [FSTYPE_SYSV2] "SystemV Release 2",
279 [FSTYPE_COH] "Coherent",
280 [FSTYPE_V7] "V7",
281 [FSTYPE_AFS] "AFS",
282};
283
284static void (*flavour_setup[])(struct super_block *) = {
285 [FSTYPE_XENIX] detected_xenix,
286 [FSTYPE_SYSV4] detected_sysv4,
287 [FSTYPE_SYSV2] detected_sysv2,
288 [FSTYPE_COH] detected_coherent,
289 [FSTYPE_V7] detected_v7,
290 [FSTYPE_AFS] detected_sysv4,
291};
292
293static int complete_read_super(struct super_block *sb, int silent, int size)
294{
295 struct inode *root_inode;
296 char *found = flavour_names[sb->sv_type];
297 u_char n_bits = size+8;
298 int bsize = 1 << n_bits;
299 int bsize_4 = bsize >> 2;
300
301 sb->sv_firstinodezone = 2;
302
303 flavour_setup[sb->sv_type](sb);
304
305 sb->sv_truncate = 1;
306 sb->sv_ndatazones = sb->sv_nzones - sb->sv_firstdatazone;
307 sb->sv_inodes_per_block = bsize >> 6;
308 sb->sv_inodes_per_block_1 = (bsize >> 6)-1;
309 sb->sv_inodes_per_block_bits = n_bits-6;
310 sb->sv_ind_per_block = bsize_4;
311 sb->sv_ind_per_block_2 = bsize_4*bsize_4;
312 sb->sv_toobig_block = 10 + bsize_4 * (1 + bsize_4 * (1 + bsize_4));
313 sb->sv_ind_per_block_bits = n_bits-2;
314
315 sb->sv_ninodes = (sb->sv_firstdatazone - sb->sv_firstinodezone)
316 << sb->sv_inodes_per_block_bits;
317
318 sb->s_blocksize = bsize;
319 sb->s_blocksize_bits = n_bits;
320 if (!silent)
321 printk("VFS: Found a %s FS (block size = %ld) on device %s\n",
322 found, sb->s_blocksize, bdevname(sb->s_dev));
323
324 sb->s_magic = SYSV_MAGIC_BASE + sb->sv_type;
325
326 sb->s_op = &sysv_sops;
327 root_inode = iget(sb,SYSV_ROOT_INO);
328 if (!root_inode || is_bad_inode(root_inode)) {
329 printk("SysV FS: get root inode failed\n");
330 return 0;
331 }
332 sb->s_root = d_alloc_root(root_inode);
333 if (!sb->s_root) {
334 iput(root_inode);
335 printk("SysV FS: get root dentry failed\n");
336 return 0;
337 }
338 if (sb->sv_truncate)
339 sb->s_root->d_op = &sysv_dentry_operations;
340 sb->s_flags |= MS_RDONLY;
341 sb->s_dirt = 1;
342 return 1;
343}
344
345static struct super_block *sysv_read_super(struct super_block *sb,
346 void *data, int silent)
347{
348 struct buffer_head *bh1;
349 struct buffer_head *bh = NULL;
350 kdev_t dev = sb->s_dev;
351 unsigned long blocknr;
352 int size = 0;
353 int i;
354
355 if (1024 != sizeof (struct xenix_super_block))
356 panic("Xenix FS: bad super-block size");
357 if ((512 != sizeof (struct sysv4_super_block))
358 || (512 != sizeof (struct sysv2_super_block)))
359 panic("SystemV FS: bad super-block size");
360 if (500 != sizeof (struct coh_super_block))
361 panic("Coherent FS: bad super-block size");
362 if (64 != sizeof (struct sysv_inode))
363 panic("sysv fs: bad i-node size");
364 set_blocksize(dev,BLOCK_SIZE);
365 sb->s_blocksize = BLOCK_SIZE;
366 sb->sv_block_base = 0;
367
368 for (i = 0; i < sizeof(flavours)/sizeof(flavours[0]) && !size; i++) {
369 brelse(bh);
370 bh = sb_bread(sb, flavours[i].block);
371 if (!bh)
372 continue;
373 size = flavours[i].test(sb, bh);
374 }
375
376 if (!size)
377 goto Eunknown;
378
379 switch (size) {
380 case 1:
381 blocknr = bh->b_blocknr << 1;
382 brelse(bh);
383 set_blocksize(dev, 512);
384 sb->s_blocksize = 512;
385 bh1 = sb_bread(sb, blocknr);
386 bh = sb_bread(sb, blocknr + 1);
387 break;
388 case 2:
389 bh1 = bh;
390 break;
391 case 3:
392 blocknr = bh->b_blocknr >> 1;
393 brelse(bh);
394 set_blocksize(dev, 2048);
395 sb->s_blocksize = 2048;
396 bh1 = bh = sb_bread(sb, blocknr);
397 break;
398 default:
399 goto Ebadsize;
400 }
401
402 if (bh && bh1) {
403 sb->sv_bh1 = bh1;
404 sb->sv_bh2 = bh;
405 if (complete_read_super(sb, silent, size))
406 return sb;
407 }
408
409 brelse(bh1);
410 brelse(bh);
411 set_blocksize(sb->s_dev,BLOCK_SIZE);
412 printk("oldfs: cannot read superblock\n");
413failed:
414 return NULL;
415
416Eunknown:
417 brelse(bh);
418 if (!silent)
419 printk("VFS: unable to find oldfs superblock on device %s\n",
420 bdevname(dev));
421 goto failed;
422Ebadsize:
423 brelse(bh);
424 if (!silent)
425 printk("VFS: oldfs: unsupported block size (%dKb)\n",
426 1<<(size-2));
427 goto failed;
428}
429
430static struct super_block *v7_read_super(struct super_block *sb,void *data,
431 int silent)
432{
433 struct buffer_head *bh, *bh2 = NULL;
434 kdev_t dev = sb->s_dev;
435 struct v7_super_block *v7sb;
436 struct sysv_inode *v7i;
437
438 if (440 != sizeof (struct v7_super_block))
439 panic("V7 FS: bad super-block size");
440 if (64 != sizeof (struct sysv_inode))
441 panic("sysv fs: bad i-node size");
442
443 sb->sv_type = FSTYPE_V7;
444 sb->sv_bytesex = BYTESEX_PDP;
445
446 set_blocksize(dev, 512);
447 sb->s_blocksize = 512;
448
449 if ((bh = sb_bread(sb, 1)) == NULL) {
450 if (!silent)
451 printk("VFS: unable to read V7 FS superblock on "
452 "device %s.\n", bdevname(dev));
453 goto failed;
454 }
455
456
457 v7sb = (struct v7_super_block *) bh->b_data;
458 if (fs16_to_cpu(sb,v7sb->s_nfree) > V7_NICFREE ||
459 fs16_to_cpu(sb,v7sb->s_ninode) > V7_NICINOD ||
460 fs32_to_cpu(sb,v7sb->s_time) == 0)
461 goto failed;
462
463
464
465 if ((bh2 = sb_bread(sb, 2)) == NULL)
466 goto failed;
467 v7i = (struct sysv_inode *)(bh2->b_data + 64);
468 if ((fs16_to_cpu(sb,v7i->i_mode) & ~0777) != S_IFDIR ||
469 (fs32_to_cpu(sb,v7i->i_size) == 0) ||
470 (fs32_to_cpu(sb,v7i->i_size) & 017) != 0)
471 goto failed;
472 brelse(bh2);
473
474 sb->sv_bh1 = bh;
475 sb->sv_bh2 = bh;
476 if (complete_read_super(sb, silent, 1))
477 return sb;
478
479failed:
480 brelse(bh2);
481 brelse(bh);
482 return NULL;
483}
484
485
486
487static DECLARE_FSTYPE_DEV(sysv_fs_type, "sysv", sysv_read_super);
488static DECLARE_FSTYPE_DEV(v7_fs_type, "v7", v7_read_super);
489
490static int __init init_sysv_fs(void)
491{
492 int err = register_filesystem(&sysv_fs_type);
493 if (!err)
494 err = register_filesystem(&v7_fs_type);
495 return err;
496}
497
498static void __exit exit_sysv_fs(void)
499{
500 unregister_filesystem(&sysv_fs_type);
501 unregister_filesystem(&v7_fs_type);
502}
503
504EXPORT_NO_SYMBOLS;
505
506module_init(init_sysv_fs)
507module_exit(exit_sysv_fs)
508MODULE_LICENSE("GPL");
509
