File: /usr/src/linux/fs/hpfs/super.c
1 /*
2 * linux/fs/hpfs/super.c
3 *
4 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5 *
6 * mouning, unmounting, error handling
7 */
8
9 #include <linux/string.h>
10 #include "hpfs_fn.h"
11 #include <linux/module.h>
12 #include <linux/init.h>
13
14 /* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */
15
16 static void mark_dirty(struct super_block *s)
17 {
18 if (s->s_hpfs_chkdsk && !(s->s_flags & MS_RDONLY)) {
19 struct buffer_head *bh;
20 struct hpfs_spare_block *sb;
21 if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
22 sb->dirty = 1;
23 sb->old_wrote = 0;
24 mark_buffer_dirty(bh);
25 brelse(bh);
26 }
27 }
28 }
29
30 /* Mark the filesystem clean (mark it dirty for chkdsk if chkdsk==2 or if there
31 were errors) */
32
33 static void unmark_dirty(struct super_block *s)
34 {
35 struct buffer_head *bh;
36 struct hpfs_spare_block *sb;
37 if (s->s_flags & MS_RDONLY) return;
38 if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
39 sb->dirty = s->s_hpfs_chkdsk > 1 - s->s_hpfs_was_error;
40 sb->old_wrote = s->s_hpfs_chkdsk >= 2 && !s->s_hpfs_was_error;
41 mark_buffer_dirty(bh);
42 brelse(bh);
43 }
44 }
45
46 /* Filesystem error... */
47
48 #define ERR_BUF_SIZE 1024
49
50 void hpfs_error(struct super_block *s, char *m,...)
51 {
52 char *buf;
53 va_list l;
54 va_start(l, m);
55 if (!(buf = kmalloc(ERR_BUF_SIZE, GFP_KERNEL)))
56 printk("HPFS: No memory for error message '%s'\n",m);
57 else if (vsprintf(buf, m, l) >= ERR_BUF_SIZE)
58 printk("HPFS: Grrrr... Kernel memory corrupted ... going on, but it'll crash very soon :-(\n");
59 printk("HPFS: filesystem error: ");
60 if (buf) printk("%s", buf);
61 else printk("%s\n",m);
62 if (!s->s_hpfs_was_error) {
63 if (s->s_hpfs_err == 2) {
64 printk("; crashing the system because you wanted it\n");
65 mark_dirty(s);
66 panic("HPFS panic");
67 } else if (s->s_hpfs_err == 1) {
68 if (s->s_flags & MS_RDONLY) printk("; already mounted read-only\n");
69 else {
70 printk("; remounting read-only\n");
71 mark_dirty(s);
72 s->s_flags |= MS_RDONLY;
73 }
74 } else if (s->s_flags & MS_RDONLY) printk("; going on - but anything won't be destroyed because it's read-only\n");
75 else printk("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
76 } else printk("\n");
77 if (buf) kfree(buf);
78 s->s_hpfs_was_error = 1;
79 }
80
81 /*
82 * A little trick to detect cycles in many hpfs structures and don't let the
83 * kernel crash on corrupted filesystem. When first called, set c2 to 0.
84 *
85 * BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
86 * nested each in other, chkdsk locked up happilly.
87 */
88
89 int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
90 char *msg)
91 {
92 if (*c2 && *c1 == key) {
93 hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
94 return 1;
95 }
96 (*c2)++;
97 if (!((*c2 - 1) & *c2)) *c1 = key;
98 return 0;
99 }
100
101 void hpfs_put_super(struct super_block *s)
102 {
103 if (s->s_hpfs_cp_table) kfree(s->s_hpfs_cp_table);
104 if (s->s_hpfs_bmp_dir) kfree(s->s_hpfs_bmp_dir);
105 unmark_dirty(s);
106 }
107
108 unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
109 {
110 struct quad_buffer_head qbh;
111 unsigned *bits;
112 unsigned i, count;
113 if (!(bits = hpfs_map_4sectors(s, secno, &qbh, 4))) return 0;
114 count = 0;
115 for (i = 0; i < 2048 / sizeof(unsigned); i++) {
116 unsigned b;
117 if (!bits[i]) continue;
118 for (b = bits[i]; b; b>>=1) count += b & 1;
119 }
120 hpfs_brelse4(&qbh);
121 return count;
122 }
123
124 static unsigned count_bitmaps(struct super_block *s)
125 {
126 unsigned n, count, n_bands;
127 n_bands = (s->s_hpfs_fs_size + 0x3fff) >> 14;
128 count = 0;
129 for (n = 0; n < n_bands; n++)
130 count += hpfs_count_one_bitmap(s, s->s_hpfs_bmp_dir[n]);
131 return count;
132 }
133
134 int hpfs_statfs(struct super_block *s, struct statfs *buf)
135 {
136 /*if (s->s_hpfs_n_free == -1) {*/
137 s->s_hpfs_n_free = count_bitmaps(s);
138 s->s_hpfs_n_free_dnodes = hpfs_count_one_bitmap(s, s->s_hpfs_dmap);
139 /*}*/
140 buf->f_type = s->s_magic;
141 buf->f_bsize = 512;
142 buf->f_blocks = s->s_hpfs_fs_size;
143 buf->f_bfree = s->s_hpfs_n_free;
144 buf->f_bavail = s->s_hpfs_n_free;
145 buf->f_files = s->s_hpfs_dirband_size / 4;
146 buf->f_ffree = s->s_hpfs_n_free_dnodes;
147 buf->f_namelen = 254;
148 return 0;
149 }
150
151 /* Super operations */
152
153 static struct super_operations hpfs_sops =
154 {
155 read_inode: hpfs_read_inode,
156 delete_inode: hpfs_delete_inode,
157 put_super: hpfs_put_super,
158 statfs: hpfs_statfs,
159 remount_fs: hpfs_remount_fs,
160 };
161
162 /*
163 * A tiny parser for option strings, stolen from dosfs.
164 *
165 * Stolen again from read-only hpfs.
166 */
167
168 int parse_opts(char *opts, uid_t *uid, gid_t *gid, umode_t *umask,
169 int *lowercase, int *conv, int *eas, int *chk, int *errs,
170 int *chkdsk, int *timeshift)
171 {
172 char *p, *rhs;
173
174 if (!opts)
175 return 1;
176
177 /*printk("Parsing opts: '%s'\n",opts);*/
178
179 for (p = strtok(opts, ","); p != 0; p = strtok(0, ",")) {
180 if ((rhs = strchr(p, '=')) != 0)
181 *rhs++ = '\0';
182 if (!strcmp(p, "help")) return 2;
183 if (!strcmp(p, "uid")) {
184 if (!rhs || !*rhs)
185 return 0;
186 *uid = simple_strtoul(rhs, &rhs, 0);
187 if (*rhs)
188 return 0;
189 }
190 else if (!strcmp(p, "gid")) {
191 if (!rhs || !*rhs)
192 return 0;
193 *gid = simple_strtoul(rhs, &rhs, 0);
194 if (*rhs)
195 return 0;
196 }
197 else if (!strcmp(p, "umask")) {
198 if (!rhs || !*rhs)
199 return 0;
200 *umask = simple_strtoul(rhs, &rhs, 8);
201 if (*rhs)
202 return 0;
203 }
204 else if (!strcmp(p, "timeshift")) {
205 int m = 1;
206 if (!rhs || !*rhs)
207 return 0;
208 if (*rhs == '-') m = -1;
209 if (*rhs == '+' || *rhs == '-') rhs++;
210 *timeshift = simple_strtoul(rhs, &rhs, 0) * m;
211 if (*rhs)
212 return 0;
213 }
214 else if (!strcmp(p, "case")) {
215 if (!rhs || !*rhs)
216 return 0;
217 if (!strcmp(rhs, "lower"))
218 *lowercase = 1;
219 else if (!strcmp(rhs, "asis"))
220 *lowercase = 0;
221 else
222 return 0;
223 }
224 else if (!strcmp(p, "conv")) {
225 if (!rhs || !*rhs)
226 return 0;
227 if (!strcmp(rhs, "binary"))
228 *conv = CONV_BINARY;
229 else if (!strcmp(rhs, "text"))
230 *conv = CONV_TEXT;
231 else if (!strcmp(rhs, "auto"))
232 *conv = CONV_AUTO;
233 else
234 return 0;
235 }
236 else if (!strcmp(p, "check")) {
237 if (!rhs || !*rhs)
238 return 0;
239 if (!strcmp(rhs, "none"))
240 *chk = 0;
241 else if (!strcmp(rhs, "normal"))
242 *chk = 1;
243 else if (!strcmp(rhs, "strict"))
244 *chk = 2;
245 else
246 return 0;
247 }
248 else if (!strcmp(p, "errors")) {
249 if (!rhs || !*rhs)
250 return 0;
251 if (!strcmp(rhs, "continue"))
252 *errs = 0;
253 else if (!strcmp(rhs, "remount-ro"))
254 *errs = 1;
255 else if (!strcmp(rhs, "panic"))
256 *errs = 2;
257 else
258 return 0;
259 }
260 else if (!strcmp(p, "eas")) {
261 if (!rhs || !*rhs)
262 return 0;
263 if (!strcmp(rhs, "no"))
264 *eas = 0;
265 else if (!strcmp(rhs, "ro"))
266 *eas = 1;
267 else if (!strcmp(rhs, "rw"))
268 *eas = 2;
269 else
270 return 0;
271 }
272 else if (!strcmp(p, "chkdsk")) {
273 if (!rhs || !*rhs)
274 return 0;
275 if (!strcmp(rhs, "no"))
276 *chkdsk = 0;
277 else if (!strcmp(rhs, "errors"))
278 *chkdsk = 1;
279 else if (!strcmp(rhs, "always"))
280 *chkdsk = 2;
281 else
282 return 0;
283 }
284 else
285 return 0;
286 }
287 return 1;
288 }
289
290 static inline void hpfs_help(void)
291 {
292 printk("\n\
293 HPFS filesystem options:\n\
294 help do not mount and display this text\n\
295 uid=xxx set uid of files that don't have uid specified in eas\n\
296 gid=xxx set gid of files that don't have gid specified in eas\n\
297 umask=xxx set mode of files that don't have mode specified in eas\n\
298 case=lower lowercase all files\n\
299 case=asis do not lowercase files (default)\n\
300 conv=binary do not convert CR/LF -> LF (default)\n\
301 conv=auto convert only files with known text extensions\n\
302 conv=text convert all files\n\
303 check=none no fs checks - kernel may crash on corrupted filesystem\n\
304 check=normal do some checks - it should not crash (default)\n\
305 check=strict do extra time-consuming checks, used for debugging\n\
306 errors=continue continue on errors\n\
307 errors=remount-ro remount read-only if errors found (default)\n\
308 errors=panic panic on errors\n\
309 chkdsk=no do not mark fs for chkdsking even if there were errors\n\
310 chkdsk=errors mark fs dirty if errors found (default)\n\
311 chkdsk=always always mark fs dirty - used for debugging\n\
312 eas=no ignore extended attributes\n\
313 eas=ro read but do not write extended attributes\n\
314 eas=rw r/w eas => enables chmod, chown, mknod, ln -s (default)\n\
315 timeshift=nnn add nnn seconds to file times\n\
316 \n");
317 }
318
319 int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
320 {
321 uid_t uid;
322 gid_t gid;
323 umode_t umask;
324 int lowercase, conv, eas, chk, errs, chkdsk, timeshift;
325 int o;
326
327 *flags |= MS_NOATIME;
328
329 uid = s->s_hpfs_uid; gid = s->s_hpfs_gid;
330 umask = 0777 & ~s->s_hpfs_mode;
331 lowercase = s->s_hpfs_lowercase; conv = s->s_hpfs_conv;
332 eas = s->s_hpfs_eas; chk = s->s_hpfs_chk; chkdsk = s->s_hpfs_chkdsk;
333 errs = s->s_hpfs_err; timeshift = s->s_hpfs_timeshift;
334
335 if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase, &conv,
336 &eas, &chk, &errs, &chkdsk, ×hift))) {
337 printk("HPFS: bad mount options.\n");
338 return 1;
339 }
340 if (o == 2) {
341 hpfs_help();
342 return 1;
343 }
344 if (timeshift != s->s_hpfs_timeshift) {
345 printk("HPFS: timeshift can't be changed using remount.\n");
346 return 1;
347 }
348
349 unmark_dirty(s);
350
351 s->s_hpfs_uid = uid; s->s_hpfs_gid = gid;
352 s->s_hpfs_mode = 0777 & ~umask;
353 s->s_hpfs_lowercase = lowercase; s->s_hpfs_conv = conv;
354 s->s_hpfs_eas = eas; s->s_hpfs_chk = chk; s->s_hpfs_chkdsk = chkdsk;
355 s->s_hpfs_err = errs; s->s_hpfs_timeshift = timeshift;
356
357 if (!(*flags & MS_RDONLY)) mark_dirty(s);
358
359 return 0;
360 }
361
362 struct super_block *hpfs_read_super(struct super_block *s, void *options,
363 int silent)
364 {
365 kdev_t dev;
366 struct buffer_head *bh0, *bh1, *bh2;
367 struct hpfs_boot_block *bootblock;
368 struct hpfs_super_block *superblock;
369 struct hpfs_spare_block *spareblock;
370
371 uid_t uid;
372 gid_t gid;
373 umode_t umask;
374 int lowercase, conv, eas, chk, errs, chkdsk, timeshift;
375
376 dnode_secno root_dno;
377 struct hpfs_dirent *de = NULL;
378 struct quad_buffer_head qbh;
379
380 int o;
381
382 s->s_hpfs_bmp_dir = NULL;
383 s->s_hpfs_cp_table = NULL;
384
385 s->s_hpfs_creation_de_lock = s->s_hpfs_rd_inode = 0;
386 init_waitqueue_head(&s->s_hpfs_creation_de);
387 init_waitqueue_head(&s->s_hpfs_iget_q);
388
389 uid = current->uid;
390 gid = current->gid;
391 umask = current->fs->umask;
392 lowercase = 0;
393 conv = CONV_BINARY;
394 eas = 2;
395 chk = 1;
396 errs = 1;
397 chkdsk = 1;
398 timeshift = 0;
399
400 if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase, &conv,
401 &eas, &chk, &errs, &chkdsk, ×hift))) {
402 printk("HPFS: bad mount options.\n");
403 goto bail0;
404 }
405 if (o==2) {
406 hpfs_help();
407 goto bail0;
408 }
409
410 /*s->s_hpfs_mounting = 1;*/
411 dev = s->s_dev;
412 set_blocksize(dev, 512);
413 s->s_hpfs_fs_size = -1;
414 if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
415 if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
416 if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
417
418 /* Check magics */
419 if (/*bootblock->magic != BB_MAGIC
420 ||*/ superblock->magic != SB_MAGIC
421 || spareblock->magic != SP_MAGIC) {
422 if (!silent) printk("HPFS: Bad magic ... probably not HPFS\n");
423 goto bail4;
424 }
425
426 /* Check version */
427 if (!(s->s_flags & MS_RDONLY) &&
428 superblock->funcversion != 2 && superblock->funcversion != 3) {
429 printk("HPFS: Bad version %d,%d. Mount readonly to go around\n",
430 (int)superblock->version, (int)superblock->funcversion);
431 printk("HPFS: please try recent version of HPFS driver at http://artax.karlin.mff.cuni.cz/~mikulas/vyplody/hpfs/index-e.cgi and if it still can't understand this format, contact author - mikulas@artax.karlin.mff.cuni.cz\n");
432 goto bail4;
433 }
434
435 s->s_flags |= MS_NOATIME;
436
437 /* Fill superblock stuff */
438 s->s_magic = HPFS_SUPER_MAGIC;
439 s->s_blocksize = 512;
440 s->s_blocksize_bits = 9;
441 s->s_op = &hpfs_sops;
442
443 s->s_hpfs_root = superblock->root;
444 s->s_hpfs_fs_size = superblock->n_sectors;
445 s->s_hpfs_bitmaps = superblock->bitmaps;
446 s->s_hpfs_dirband_start = superblock->dir_band_start;
447 s->s_hpfs_dirband_size = superblock->n_dir_band;
448 s->s_hpfs_dmap = superblock->dir_band_bitmap;
449 s->s_hpfs_uid = uid;
450 s->s_hpfs_gid = gid;
451 s->s_hpfs_mode = 0777 & ~umask;
452 s->s_hpfs_n_free = -1;
453 s->s_hpfs_n_free_dnodes = -1;
454 s->s_hpfs_lowercase = lowercase;
455 s->s_hpfs_conv = conv;
456 s->s_hpfs_eas = eas;
457 s->s_hpfs_chk = chk;
458 s->s_hpfs_chkdsk = chkdsk;
459 s->s_hpfs_err = errs;
460 s->s_hpfs_timeshift = timeshift;
461 s->s_hpfs_was_error = 0;
462 s->s_hpfs_cp_table = NULL;
463 s->s_hpfs_c_bitmap = -1;
464
465 /* Load bitmap directory */
466 if (!(s->s_hpfs_bmp_dir = hpfs_load_bitmap_directory(s, superblock->bitmaps)))
467 goto bail4;
468
469 /* Check for general fs errors*/
470 if (spareblock->dirty && !spareblock->old_wrote) {
471 if (errs == 2) {
472 printk("HPFS: Improperly stopped, not mounted\n");
473 goto bail4;
474 }
475 hpfs_error(s, "improperly stopped");
476 }
477
478 if (!(s->s_flags & MS_RDONLY)) {
479 spareblock->dirty = 1;
480 spareblock->old_wrote = 0;
481 mark_buffer_dirty(bh2);
482 }
483
484 if (spareblock->hotfixes_used || spareblock->n_spares_used) {
485 if (errs >= 2) {
486 printk("HPFS: Hotfixes not supported here, try chkdsk\n");
487 mark_dirty(s);
488 goto bail4;
489 }
490 hpfs_error(s, "hotfixes not supported here, try chkdsk");
491 if (errs == 0) printk("HPFS: Proceeding, but your filesystem will be probably corrupted by this driver...\n");
492 else printk("HPFS: This driver may read bad files or crash when operating on disk with hotfixes.\n");
493 }
494 if (spareblock->n_dnode_spares != spareblock->n_dnode_spares_free) {
495 if (errs >= 2) {
496 printk("HPFS: Spare dnodes used, try chkdsk\n");
497 mark_dirty(s);
498 goto bail4;
499 }
500 hpfs_error(s, "warning: spare dnodes used, try chkdsk");
501 if (errs == 0) printk("HPFS: Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
502 }
503 if (chk) {
504 unsigned a;
505 if (superblock->dir_band_end - superblock->dir_band_start + 1 != superblock->n_dir_band ||
506 superblock->dir_band_end < superblock->dir_band_start || superblock->n_dir_band > 0x4000) {
507 hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
508 superblock->dir_band_start, superblock->dir_band_end, superblock->n_dir_band);
509 goto bail4;
510 }
511 a = s->s_hpfs_dirband_size;
512 s->s_hpfs_dirband_size = 0;
513 if (hpfs_chk_sectors(s, superblock->dir_band_start, superblock->n_dir_band, "dir_band") ||
514 hpfs_chk_sectors(s, superblock->dir_band_bitmap, 4, "dir_band_bitmap") ||
515 hpfs_chk_sectors(s, superblock->bitmaps, 4, "bitmaps")) {
516 mark_dirty(s);
517 goto bail4;
518 }
519 s->s_hpfs_dirband_size = a;
520 } else printk("HPFS: You really don't want any checks? You are crazy...\n");
521
522 /* Load code page table */
523 if (spareblock->n_code_pages)
524 if (!(s->s_hpfs_cp_table = hpfs_load_code_page(s, spareblock->code_page_dir)))
525 printk("HPFS: Warning: code page support is disabled\n");
526
527 brelse(bh2);
528 brelse(bh1);
529 brelse(bh0);
530
531 hpfs_lock_iget(s, 1);
532 s->s_root = d_alloc_root(iget(s, s->s_hpfs_root));
533 hpfs_unlock_iget(s);
534 if (!s->s_root || !s->s_root->d_inode) {
535 printk("HPFS: iget failed. Why???\n");
536 goto bail0;
537 }
538 hpfs_set_dentry_operations(s->s_root);
539
540 /*
541 * find the root directory's . pointer & finish filling in the inode
542 */
543
544 root_dno = hpfs_fnode_dno(s, s->s_hpfs_root);
545 if (root_dno)
546 de = map_dirent(s->s_root->d_inode, root_dno, "\001\001", 2, NULL, &qbh);
547 if (!root_dno || !de) hpfs_error(s, "unable to find root dir");
548 else {
549 s->s_root->d_inode->i_atime = local_to_gmt(s, de->read_date);
550 s->s_root->d_inode->i_mtime = local_to_gmt(s, de->write_date);
551 s->s_root->d_inode->i_ctime = local_to_gmt(s, de->creation_date);
552 s->s_root->d_inode->i_hpfs_ea_size = de->ea_size;
553 s->s_root->d_inode->i_hpfs_parent_dir = s->s_root->d_inode->i_ino;
554 if (s->s_root->d_inode->i_size == -1) s->s_root->d_inode->i_size = 2048;
555 if (s->s_root->d_inode->i_blocks == -1) s->s_root->d_inode->i_blocks = 5;
556 }
557 if (de) hpfs_brelse4(&qbh);
558
559 return s;
560
561 bail4: brelse(bh2);
562 bail3: brelse(bh1);
563 bail2: brelse(bh0);
564 bail1:
565 bail0:
566 if (s->s_hpfs_bmp_dir) kfree(s->s_hpfs_bmp_dir);
567 if (s->s_hpfs_cp_table) kfree(s->s_hpfs_cp_table);
568 return NULL;
569 }
570
571 DECLARE_FSTYPE_DEV(hpfs_fs_type, "hpfs", hpfs_read_super);
572
573 static int __init init_hpfs_fs(void)
574 {
575 return register_filesystem(&hpfs_fs_type);
576 }
577
578 static void __exit exit_hpfs_fs(void)
579 {
580 unregister_filesystem(&hpfs_fs_type);
581 }
582
583 EXPORT_NO_SYMBOLS;
584
585 module_init(init_hpfs_fs)
586 module_exit(exit_hpfs_fs)
587