Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/vfat/namei.c | |
3 | * | |
4 | * Written 1992,1993 by Werner Almesberger | |
5 | * | |
6 | * Windows95/Windows NT compatible extended MSDOS filesystem | |
7 | * by Gordon Chaffee Copyright (C) 1995. Send bug reports for the | |
8 | * VFAT filesystem to <chaffee@cs.berkeley.edu>. Specify | |
9 | * what file operation caused you trouble and if you can duplicate | |
10 | * the problem, send a script that demonstrates it. | |
11 | * | |
12 | * Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de> | |
13 | * | |
14 | * Support Multibyte characters and cleanup by | |
15 | * OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> | |
16 | */ | |
17 | ||
18 | #include <linux/module.h> | |
19 | ||
20 | #include <linux/jiffies.h> | |
21 | #include <linux/msdos_fs.h> | |
22 | #include <linux/ctype.h> | |
23 | #include <linux/slab.h> | |
24 | #include <linux/smp_lock.h> | |
25 | #include <linux/buffer_head.h> | |
26 | #include <linux/namei.h> | |
27 | ||
28 | static int vfat_revalidate(struct dentry *dentry, struct nameidata *nd) | |
29 | { | |
30 | int ret = 1; | |
31 | ||
32 | if (!dentry->d_inode && | |
33 | nd && !(nd->flags & LOOKUP_CONTINUE) && (nd->flags & LOOKUP_CREATE)) | |
34 | /* | |
35 | * negative dentry is dropped, in order to make sure | |
36 | * to use the name which a user desires if this is | |
37 | * create path. | |
38 | */ | |
39 | ret = 0; | |
40 | else { | |
41 | spin_lock(&dentry->d_lock); | |
42 | if (dentry->d_time != dentry->d_parent->d_inode->i_version) | |
43 | ret = 0; | |
44 | spin_unlock(&dentry->d_lock); | |
45 | } | |
46 | return ret; | |
47 | } | |
48 | ||
49 | /* returns the length of a struct qstr, ignoring trailing dots */ | |
50 | static unsigned int vfat_striptail_len(struct qstr *qstr) | |
51 | { | |
52 | unsigned int len = qstr->len; | |
53 | ||
54 | while (len && qstr->name[len - 1] == '.') | |
55 | len--; | |
56 | return len; | |
57 | } | |
58 | ||
59 | /* | |
60 | * Compute the hash for the vfat name corresponding to the dentry. | |
61 | * Note: if the name is invalid, we leave the hash code unchanged so | |
62 | * that the existing dentry can be used. The vfat fs routines will | |
63 | * return ENOENT or EINVAL as appropriate. | |
64 | */ | |
65 | static int vfat_hash(struct dentry *dentry, struct qstr *qstr) | |
66 | { | |
67 | qstr->hash = full_name_hash(qstr->name, vfat_striptail_len(qstr)); | |
68 | return 0; | |
69 | } | |
70 | ||
71 | /* | |
72 | * Compute the hash for the vfat name corresponding to the dentry. | |
73 | * Note: if the name is invalid, we leave the hash code unchanged so | |
74 | * that the existing dentry can be used. The vfat fs routines will | |
75 | * return ENOENT or EINVAL as appropriate. | |
76 | */ | |
77 | static int vfat_hashi(struct dentry *dentry, struct qstr *qstr) | |
78 | { | |
79 | struct nls_table *t = MSDOS_SB(dentry->d_inode->i_sb)->nls_io; | |
80 | const unsigned char *name; | |
81 | unsigned int len; | |
82 | unsigned long hash; | |
83 | ||
84 | name = qstr->name; | |
85 | len = vfat_striptail_len(qstr); | |
86 | ||
87 | hash = init_name_hash(); | |
88 | while (len--) | |
89 | hash = partial_name_hash(nls_tolower(t, *name++), hash); | |
90 | qstr->hash = end_name_hash(hash); | |
91 | ||
92 | return 0; | |
93 | } | |
94 | ||
95 | /* | |
96 | * Case insensitive compare of two vfat names. | |
97 | */ | |
98 | static int vfat_cmpi(struct dentry *dentry, struct qstr *a, struct qstr *b) | |
99 | { | |
100 | struct nls_table *t = MSDOS_SB(dentry->d_inode->i_sb)->nls_io; | |
101 | unsigned int alen, blen; | |
102 | ||
103 | /* A filename cannot end in '.' or we treat it like it has none */ | |
104 | alen = vfat_striptail_len(a); | |
105 | blen = vfat_striptail_len(b); | |
106 | if (alen == blen) { | |
107 | if (nls_strnicmp(t, a->name, b->name, alen) == 0) | |
108 | return 0; | |
109 | } | |
110 | return 1; | |
111 | } | |
112 | ||
113 | /* | |
114 | * Case sensitive compare of two vfat names. | |
115 | */ | |
116 | static int vfat_cmp(struct dentry *dentry, struct qstr *a, struct qstr *b) | |
117 | { | |
118 | unsigned int alen, blen; | |
119 | ||
120 | /* A filename cannot end in '.' or we treat it like it has none */ | |
121 | alen = vfat_striptail_len(a); | |
122 | blen = vfat_striptail_len(b); | |
123 | if (alen == blen) { | |
124 | if (strncmp(a->name, b->name, alen) == 0) | |
125 | return 0; | |
126 | } | |
127 | return 1; | |
128 | } | |
129 | ||
130 | static struct dentry_operations vfat_dentry_ops[4] = { | |
131 | { | |
132 | .d_hash = vfat_hashi, | |
133 | .d_compare = vfat_cmpi, | |
134 | }, | |
135 | { | |
136 | .d_revalidate = vfat_revalidate, | |
137 | .d_hash = vfat_hashi, | |
138 | .d_compare = vfat_cmpi, | |
139 | }, | |
140 | { | |
141 | .d_hash = vfat_hash, | |
142 | .d_compare = vfat_cmp, | |
143 | }, | |
144 | { | |
145 | .d_revalidate = vfat_revalidate, | |
146 | .d_hash = vfat_hash, | |
147 | .d_compare = vfat_cmp, | |
148 | } | |
149 | }; | |
150 | ||
151 | /* Characters that are undesirable in an MS-DOS file name */ | |
152 | ||
153 | static inline wchar_t vfat_bad_char(wchar_t w) | |
154 | { | |
155 | return (w < 0x0020) | |
156 | || (w == '*') || (w == '?') || (w == '<') || (w == '>') | |
157 | || (w == '|') || (w == '"') || (w == ':') || (w == '/') | |
158 | || (w == '\\'); | |
159 | } | |
160 | ||
161 | static inline wchar_t vfat_replace_char(wchar_t w) | |
162 | { | |
163 | return (w == '[') || (w == ']') || (w == ';') || (w == ',') | |
164 | || (w == '+') || (w == '='); | |
165 | } | |
166 | ||
167 | static wchar_t vfat_skip_char(wchar_t w) | |
168 | { | |
169 | return (w == '.') || (w == ' '); | |
170 | } | |
171 | ||
172 | static inline int vfat_is_used_badchars(const wchar_t *s, int len) | |
173 | { | |
174 | int i; | |
175 | ||
176 | for (i = 0; i < len; i++) | |
177 | if (vfat_bad_char(s[i])) | |
178 | return -EINVAL; | |
1da177e4 | 179 | |
f22032ba | 180 | if (s[i - 1] == ' ') /* last character cannot be space */ |
1da177e4 | 181 | return -EINVAL; |
f22032ba | 182 | |
1da177e4 LT |
183 | return 0; |
184 | } | |
185 | ||
186 | static int vfat_find_form(struct inode *dir, unsigned char *name) | |
187 | { | |
188 | struct fat_slot_info sinfo; | |
189 | int err = fat_scan(dir, name, &sinfo); | |
190 | if (err) | |
191 | return -ENOENT; | |
192 | brelse(sinfo.bh); | |
193 | return 0; | |
194 | } | |
195 | ||
196 | /* | |
197 | * 1) Valid characters for the 8.3 format alias are any combination of | |
198 | * letters, uppercase alphabets, digits, any of the | |
199 | * following special characters: | |
200 | * $ % ' ` - @ { } ~ ! # ( ) & _ ^ | |
201 | * In this case Longfilename is not stored in disk. | |
202 | * | |
203 | * WinNT's Extension: | |
204 | * File name and extension name is contain uppercase/lowercase | |
205 | * only. And it is expressed by CASE_LOWER_BASE and CASE_LOWER_EXT. | |
206 | * | |
207 | * 2) File name is 8.3 format, but it contain the uppercase and | |
208 | * lowercase char, muliti bytes char, etc. In this case numtail is not | |
209 | * added, but Longfilename is stored. | |
210 | * | |
211 | * 3) When the one except for the above, or the following special | |
212 | * character are contained: | |
213 | * . [ ] ; , + = | |
214 | * numtail is added, and Longfilename must be stored in disk . | |
215 | */ | |
216 | struct shortname_info { | |
217 | unsigned char lower:1, | |
218 | upper:1, | |
219 | valid:1; | |
220 | }; | |
221 | #define INIT_SHORTNAME_INFO(x) do { \ | |
222 | (x)->lower = 1; \ | |
223 | (x)->upper = 1; \ | |
224 | (x)->valid = 1; \ | |
225 | } while (0) | |
226 | ||
227 | static inline int to_shortname_char(struct nls_table *nls, | |
228 | unsigned char *buf, int buf_size, | |
229 | wchar_t *src, struct shortname_info *info) | |
230 | { | |
231 | int len; | |
232 | ||
233 | if (vfat_skip_char(*src)) { | |
234 | info->valid = 0; | |
235 | return 0; | |
236 | } | |
237 | if (vfat_replace_char(*src)) { | |
238 | info->valid = 0; | |
239 | buf[0] = '_'; | |
240 | return 1; | |
241 | } | |
242 | ||
243 | len = nls->uni2char(*src, buf, buf_size); | |
244 | if (len <= 0) { | |
245 | info->valid = 0; | |
246 | buf[0] = '_'; | |
247 | len = 1; | |
248 | } else if (len == 1) { | |
249 | unsigned char prev = buf[0]; | |
250 | ||
251 | if (buf[0] >= 0x7F) { | |
252 | info->lower = 0; | |
253 | info->upper = 0; | |
254 | } | |
255 | ||
256 | buf[0] = nls_toupper(nls, buf[0]); | |
257 | if (isalpha(buf[0])) { | |
258 | if (buf[0] == prev) | |
259 | info->lower = 0; | |
260 | else | |
261 | info->upper = 0; | |
262 | } | |
263 | } else { | |
264 | info->lower = 0; | |
265 | info->upper = 0; | |
266 | } | |
267 | ||
268 | return len; | |
269 | } | |
270 | ||
271 | /* | |
272 | * Given a valid longname, create a unique shortname. Make sure the | |
273 | * shortname does not exist | |
274 | * Returns negative number on error, 0 for a normal | |
275 | * return, and 1 for valid shortname | |
276 | */ | |
277 | static int vfat_create_shortname(struct inode *dir, struct nls_table *nls, | |
278 | wchar_t *uname, int ulen, | |
279 | unsigned char *name_res, unsigned char *lcase) | |
280 | { | |
281 | struct fat_mount_options *opts = &MSDOS_SB(dir->i_sb)->options; | |
282 | wchar_t *ip, *ext_start, *end, *name_start; | |
283 | unsigned char base[9], ext[4], buf[8], *p; | |
284 | unsigned char charbuf[NLS_MAX_CHARSET_SIZE]; | |
285 | int chl, chi; | |
286 | int sz = 0, extlen, baselen, i, numtail_baselen, numtail2_baselen; | |
287 | int is_shortname; | |
288 | struct shortname_info base_info, ext_info; | |
289 | ||
290 | is_shortname = 1; | |
291 | INIT_SHORTNAME_INFO(&base_info); | |
292 | INIT_SHORTNAME_INFO(&ext_info); | |
293 | ||
294 | /* Now, we need to create a shortname from the long name */ | |
295 | ext_start = end = &uname[ulen]; | |
296 | while (--ext_start >= uname) { | |
297 | if (*ext_start == 0x002E) { /* is `.' */ | |
298 | if (ext_start == end - 1) { | |
299 | sz = ulen; | |
300 | ext_start = NULL; | |
301 | } | |
302 | break; | |
303 | } | |
304 | } | |
305 | ||
306 | if (ext_start == uname - 1) { | |
307 | sz = ulen; | |
308 | ext_start = NULL; | |
309 | } else if (ext_start) { | |
310 | /* | |
311 | * Names which start with a dot could be just | |
312 | * an extension eg. "...test". In this case Win95 | |
313 | * uses the extension as the name and sets no extension. | |
314 | */ | |
315 | name_start = &uname[0]; | |
316 | while (name_start < ext_start) { | |
317 | if (!vfat_skip_char(*name_start)) | |
318 | break; | |
319 | name_start++; | |
320 | } | |
321 | if (name_start != ext_start) { | |
322 | sz = ext_start - uname; | |
323 | ext_start++; | |
324 | } else { | |
325 | sz = ulen; | |
326 | ext_start = NULL; | |
327 | } | |
328 | } | |
329 | ||
330 | numtail_baselen = 6; | |
331 | numtail2_baselen = 2; | |
332 | for (baselen = i = 0, p = base, ip = uname; i < sz; i++, ip++) { | |
333 | chl = to_shortname_char(nls, charbuf, sizeof(charbuf), | |
334 | ip, &base_info); | |
335 | if (chl == 0) | |
336 | continue; | |
337 | ||
338 | if (baselen < 2 && (baselen + chl) > 2) | |
339 | numtail2_baselen = baselen; | |
340 | if (baselen < 6 && (baselen + chl) > 6) | |
341 | numtail_baselen = baselen; | |
342 | for (chi = 0; chi < chl; chi++) { | |
343 | *p++ = charbuf[chi]; | |
344 | baselen++; | |
345 | if (baselen >= 8) | |
346 | break; | |
347 | } | |
348 | if (baselen >= 8) { | |
349 | if ((chi < chl - 1) || (ip + 1) - uname < sz) | |
350 | is_shortname = 0; | |
351 | break; | |
352 | } | |
353 | } | |
354 | if (baselen == 0) { | |
355 | return -EINVAL; | |
356 | } | |
357 | ||
358 | extlen = 0; | |
359 | if (ext_start) { | |
360 | for (p = ext, ip = ext_start; extlen < 3 && ip < end; ip++) { | |
361 | chl = to_shortname_char(nls, charbuf, sizeof(charbuf), | |
362 | ip, &ext_info); | |
363 | if (chl == 0) | |
364 | continue; | |
365 | ||
366 | if ((extlen + chl) > 3) { | |
367 | is_shortname = 0; | |
368 | break; | |
369 | } | |
370 | for (chi = 0; chi < chl; chi++) { | |
371 | *p++ = charbuf[chi]; | |
372 | extlen++; | |
373 | } | |
374 | if (extlen >= 3) { | |
375 | if (ip + 1 != end) | |
376 | is_shortname = 0; | |
377 | break; | |
378 | } | |
379 | } | |
380 | } | |
381 | ext[extlen] = '\0'; | |
382 | base[baselen] = '\0'; | |
383 | ||
384 | /* Yes, it can happen. ".\xe5" would do it. */ | |
385 | if (base[0] == DELETED_FLAG) | |
386 | base[0] = 0x05; | |
387 | ||
388 | /* OK, at this point we know that base is not longer than 8 symbols, | |
389 | * ext is not longer than 3, base is nonempty, both don't contain | |
390 | * any bad symbols (lowercase transformed to uppercase). | |
391 | */ | |
392 | ||
393 | memset(name_res, ' ', MSDOS_NAME); | |
394 | memcpy(name_res, base, baselen); | |
395 | memcpy(name_res + 8, ext, extlen); | |
396 | *lcase = 0; | |
397 | if (is_shortname && base_info.valid && ext_info.valid) { | |
398 | if (vfat_find_form(dir, name_res) == 0) | |
399 | return -EEXIST; | |
400 | ||
401 | if (opts->shortname & VFAT_SFN_CREATE_WIN95) { | |
402 | return (base_info.upper && ext_info.upper); | |
403 | } else if (opts->shortname & VFAT_SFN_CREATE_WINNT) { | |
404 | if ((base_info.upper || base_info.lower) && | |
405 | (ext_info.upper || ext_info.lower)) { | |
406 | if (!base_info.upper && base_info.lower) | |
407 | *lcase |= CASE_LOWER_BASE; | |
408 | if (!ext_info.upper && ext_info.lower) | |
409 | *lcase |= CASE_LOWER_EXT; | |
410 | return 1; | |
411 | } | |
412 | return 0; | |
413 | } else { | |
414 | BUG(); | |
415 | } | |
416 | } | |
417 | ||
418 | if (opts->numtail == 0) | |
419 | if (vfat_find_form(dir, name_res) < 0) | |
420 | return 0; | |
421 | ||
422 | /* | |
423 | * Try to find a unique extension. This used to | |
424 | * iterate through all possibilities sequentially, | |
425 | * but that gave extremely bad performance. Windows | |
426 | * only tries a few cases before using random | |
427 | * values for part of the base. | |
428 | */ | |
429 | ||
430 | if (baselen > 6) { | |
431 | baselen = numtail_baselen; | |
432 | name_res[7] = ' '; | |
433 | } | |
434 | name_res[baselen] = '~'; | |
435 | for (i = 1; i < 10; i++) { | |
436 | name_res[baselen + 1] = i + '0'; | |
437 | if (vfat_find_form(dir, name_res) < 0) | |
438 | return 0; | |
439 | } | |
440 | ||
441 | i = jiffies & 0xffff; | |
442 | sz = (jiffies >> 16) & 0x7; | |
443 | if (baselen > 2) { | |
444 | baselen = numtail2_baselen; | |
445 | name_res[7] = ' '; | |
446 | } | |
447 | name_res[baselen + 4] = '~'; | |
448 | name_res[baselen + 5] = '1' + sz; | |
449 | while (1) { | |
450 | sprintf(buf, "%04X", i); | |
451 | memcpy(&name_res[baselen], buf, 4); | |
452 | if (vfat_find_form(dir, name_res) < 0) | |
453 | break; | |
454 | i -= 11; | |
455 | } | |
456 | return 0; | |
457 | } | |
458 | ||
459 | /* Translate a string, including coded sequences into Unicode */ | |
460 | static int | |
461 | xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, | |
462 | int *longlen, int *outlen, int escape, int utf8, | |
463 | struct nls_table *nls) | |
464 | { | |
465 | const unsigned char *ip; | |
466 | unsigned char nc; | |
467 | unsigned char *op; | |
468 | unsigned int ec; | |
469 | int i, k, fill; | |
470 | int charlen; | |
471 | ||
472 | if (utf8) { | |
473 | int name_len = strlen(name); | |
474 | ||
c7a6c4ed | 475 | *outlen = utf8_mbstowcs((wchar_t *)outname, name, PATH_MAX); |
1da177e4 LT |
476 | |
477 | /* | |
478 | * We stripped '.'s before and set len appropriately, | |
479 | * but utf8_mbstowcs doesn't care about len | |
480 | */ | |
481 | *outlen -= (name_len - len); | |
482 | ||
f22032ba KM |
483 | if (*outlen > 255) |
484 | return -ENAMETOOLONG; | |
485 | ||
1da177e4 LT |
486 | op = &outname[*outlen * sizeof(wchar_t)]; |
487 | } else { | |
488 | if (nls) { | |
489 | for (i = 0, ip = name, op = outname, *outlen = 0; | |
f22032ba | 490 | i < len && *outlen <= 255; |
1da177e4 LT |
491 | *outlen += 1) |
492 | { | |
493 | if (escape && (*ip == ':')) { | |
494 | if (i > len - 5) | |
495 | return -EINVAL; | |
496 | ec = 0; | |
497 | for (k = 1; k < 5; k++) { | |
498 | nc = ip[k]; | |
499 | ec <<= 4; | |
500 | if (nc >= '0' && nc <= '9') { | |
501 | ec |= nc - '0'; | |
502 | continue; | |
503 | } | |
504 | if (nc >= 'a' && nc <= 'f') { | |
505 | ec |= nc - ('a' - 10); | |
506 | continue; | |
507 | } | |
508 | if (nc >= 'A' && nc <= 'F') { | |
509 | ec |= nc - ('A' - 10); | |
510 | continue; | |
511 | } | |
512 | return -EINVAL; | |
513 | } | |
514 | *op++ = ec & 0xFF; | |
515 | *op++ = ec >> 8; | |
516 | ip += 5; | |
517 | i += 5; | |
518 | } else { | |
519 | if ((charlen = nls->char2uni(ip, len - i, (wchar_t *)op)) < 0) | |
520 | return -EINVAL; | |
521 | ip += charlen; | |
522 | i += charlen; | |
523 | op += 2; | |
524 | } | |
525 | } | |
f22032ba KM |
526 | if (i < len) |
527 | return -ENAMETOOLONG; | |
1da177e4 LT |
528 | } else { |
529 | for (i = 0, ip = name, op = outname, *outlen = 0; | |
f22032ba | 530 | i < len && *outlen <= 255; |
1da177e4 LT |
531 | i++, *outlen += 1) |
532 | { | |
533 | *op++ = *ip++; | |
534 | *op++ = 0; | |
535 | } | |
f22032ba KM |
536 | if (i < len) |
537 | return -ENAMETOOLONG; | |
1da177e4 LT |
538 | } |
539 | } | |
1da177e4 LT |
540 | |
541 | *longlen = *outlen; | |
542 | if (*outlen % 13) { | |
543 | *op++ = 0; | |
544 | *op++ = 0; | |
545 | *outlen += 1; | |
546 | if (*outlen % 13) { | |
547 | fill = 13 - (*outlen % 13); | |
548 | for (i = 0; i < fill; i++) { | |
549 | *op++ = 0xff; | |
550 | *op++ = 0xff; | |
551 | } | |
552 | *outlen += fill; | |
553 | } | |
554 | } | |
555 | ||
556 | return 0; | |
557 | } | |
558 | ||
559 | static int vfat_build_slots(struct inode *dir, const unsigned char *name, | |
560 | int len, int is_dir, int cluster, | |
561 | struct timespec *ts, | |
562 | struct msdos_dir_slot *slots, int *nr_slots) | |
563 | { | |
564 | struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb); | |
565 | struct fat_mount_options *opts = &sbi->options; | |
566 | struct msdos_dir_slot *ps; | |
567 | struct msdos_dir_entry *de; | |
1da177e4 LT |
568 | unsigned char cksum, lcase; |
569 | unsigned char msdos_name[MSDOS_NAME]; | |
570 | wchar_t *uname; | |
571 | __le16 time, date; | |
572 | int err, ulen, usize, i; | |
573 | loff_t offset; | |
574 | ||
575 | *nr_slots = 0; | |
1da177e4 | 576 | |
c7a6c4ed OH |
577 | uname = __getname(); |
578 | if (!uname) | |
1da177e4 LT |
579 | return -ENOMEM; |
580 | ||
1da177e4 LT |
581 | err = xlate_to_uni(name, len, (unsigned char *)uname, &ulen, &usize, |
582 | opts->unicode_xlate, opts->utf8, sbi->nls_io); | |
583 | if (err) | |
584 | goto out_free; | |
585 | ||
586 | err = vfat_is_used_badchars(uname, ulen); | |
587 | if (err) | |
588 | goto out_free; | |
589 | ||
590 | err = vfat_create_shortname(dir, sbi->nls_disk, uname, ulen, | |
591 | msdos_name, &lcase); | |
592 | if (err < 0) | |
593 | goto out_free; | |
594 | else if (err == 1) { | |
595 | de = (struct msdos_dir_entry *)slots; | |
596 | err = 0; | |
597 | goto shortname; | |
598 | } | |
599 | ||
600 | /* build the entry of long file name */ | |
451cbaa1 | 601 | cksum = fat_checksum(msdos_name); |
1da177e4 LT |
602 | |
603 | *nr_slots = usize / 13; | |
604 | for (ps = slots, i = *nr_slots; i > 0; i--, ps++) { | |
605 | ps->id = i; | |
606 | ps->attr = ATTR_EXT; | |
607 | ps->reserved = 0; | |
608 | ps->alias_checksum = cksum; | |
609 | ps->start = 0; | |
610 | offset = (i - 1) * 13; | |
611 | fatwchar_to16(ps->name0_4, uname + offset, 5); | |
612 | fatwchar_to16(ps->name5_10, uname + offset + 5, 6); | |
613 | fatwchar_to16(ps->name11_12, uname + offset + 11, 2); | |
614 | } | |
615 | slots[0].id |= 0x40; | |
616 | de = (struct msdos_dir_entry *)ps; | |
617 | ||
618 | shortname: | |
619 | /* build the entry of 8.3 alias name */ | |
620 | (*nr_slots)++; | |
621 | memcpy(de->name, msdos_name, MSDOS_NAME); | |
622 | de->attr = is_dir ? ATTR_DIR : ATTR_ARCH; | |
623 | de->lcase = lcase; | |
624 | fat_date_unix2dos(ts->tv_sec, &time, &date); | |
625 | de->time = de->ctime = time; | |
626 | de->date = de->cdate = de->adate = date; | |
627 | de->ctime_cs = 0; | |
628 | de->start = cpu_to_le16(cluster); | |
629 | de->starthi = cpu_to_le16(cluster >> 16); | |
630 | de->size = 0; | |
631 | out_free: | |
c7a6c4ed | 632 | __putname(uname); |
1da177e4 LT |
633 | return err; |
634 | } | |
635 | ||
636 | static int vfat_add_entry(struct inode *dir, struct qstr *qname, int is_dir, | |
637 | int cluster, struct timespec *ts, | |
638 | struct fat_slot_info *sinfo) | |
639 | { | |
640 | struct msdos_dir_slot *slots; | |
641 | unsigned int len; | |
642 | int err, nr_slots; | |
643 | ||
644 | len = vfat_striptail_len(qname); | |
645 | if (len == 0) | |
646 | return -ENOENT; | |
647 | ||
648 | slots = kmalloc(sizeof(*slots) * MSDOS_SLOTS, GFP_KERNEL); | |
649 | if (slots == NULL) | |
650 | return -ENOMEM; | |
651 | ||
652 | err = vfat_build_slots(dir, qname->name, len, is_dir, cluster, ts, | |
653 | slots, &nr_slots); | |
654 | if (err) | |
655 | goto cleanup; | |
656 | ||
657 | err = fat_add_entries(dir, slots, nr_slots, sinfo); | |
658 | if (err) | |
659 | goto cleanup; | |
660 | ||
661 | /* update timestamp */ | |
662 | dir->i_ctime = dir->i_mtime = dir->i_atime = *ts; | |
663 | if (IS_DIRSYNC(dir)) | |
664 | (void)fat_sync_inode(dir); | |
665 | else | |
666 | mark_inode_dirty(dir); | |
667 | cleanup: | |
668 | kfree(slots); | |
669 | return err; | |
670 | } | |
671 | ||
672 | static int vfat_find(struct inode *dir, struct qstr *qname, | |
673 | struct fat_slot_info *sinfo) | |
674 | { | |
675 | unsigned int len = vfat_striptail_len(qname); | |
676 | if (len == 0) | |
677 | return -ENOENT; | |
678 | return fat_search_long(dir, qname->name, len, sinfo); | |
679 | } | |
680 | ||
681 | static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, | |
682 | struct nameidata *nd) | |
683 | { | |
684 | struct super_block *sb = dir->i_sb; | |
685 | struct fat_slot_info sinfo; | |
686 | struct inode *inode = NULL; | |
687 | struct dentry *alias; | |
688 | int err, table; | |
689 | ||
690 | lock_kernel(); | |
691 | table = (MSDOS_SB(sb)->options.name_check == 's') ? 2 : 0; | |
692 | dentry->d_op = &vfat_dentry_ops[table]; | |
693 | ||
694 | err = vfat_find(dir, &dentry->d_name, &sinfo); | |
695 | if (err) { | |
696 | table++; | |
697 | goto error; | |
698 | } | |
699 | inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); | |
700 | brelse(sinfo.bh); | |
701 | if (IS_ERR(inode)) { | |
702 | unlock_kernel(); | |
e231c2ee | 703 | return ERR_CAST(inode); |
1da177e4 LT |
704 | } |
705 | alias = d_find_alias(inode); | |
706 | if (alias) { | |
707 | if (d_invalidate(alias) == 0) | |
708 | dput(alias); | |
709 | else { | |
710 | iput(inode); | |
711 | unlock_kernel(); | |
712 | return alias; | |
713 | } | |
714 | ||
715 | } | |
716 | error: | |
717 | unlock_kernel(); | |
718 | dentry->d_op = &vfat_dentry_ops[table]; | |
719 | dentry->d_time = dentry->d_parent->d_inode->i_version; | |
720 | dentry = d_splice_alias(inode, dentry); | |
721 | if (dentry) { | |
722 | dentry->d_op = &vfat_dentry_ops[table]; | |
723 | dentry->d_time = dentry->d_parent->d_inode->i_version; | |
724 | } | |
725 | return dentry; | |
726 | } | |
727 | ||
728 | static int vfat_create(struct inode *dir, struct dentry *dentry, int mode, | |
729 | struct nameidata *nd) | |
730 | { | |
731 | struct super_block *sb = dir->i_sb; | |
732 | struct inode *inode; | |
733 | struct fat_slot_info sinfo; | |
734 | struct timespec ts; | |
735 | int err; | |
736 | ||
737 | lock_kernel(); | |
738 | ||
739 | ts = CURRENT_TIME_SEC; | |
740 | err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &ts, &sinfo); | |
741 | if (err) | |
742 | goto out; | |
743 | dir->i_version++; | |
744 | ||
745 | inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); | |
746 | brelse(sinfo.bh); | |
747 | if (IS_ERR(inode)) { | |
748 | err = PTR_ERR(inode); | |
749 | goto out; | |
750 | } | |
751 | inode->i_version++; | |
752 | inode->i_mtime = inode->i_atime = inode->i_ctime = ts; | |
753 | /* timestamp is already written, so mark_inode_dirty() is unneeded. */ | |
754 | ||
755 | dentry->d_time = dentry->d_parent->d_inode->i_version; | |
756 | d_instantiate(dentry, inode); | |
757 | out: | |
758 | unlock_kernel(); | |
759 | return err; | |
760 | } | |
761 | ||
762 | static int vfat_rmdir(struct inode *dir, struct dentry *dentry) | |
763 | { | |
764 | struct inode *inode = dentry->d_inode; | |
765 | struct fat_slot_info sinfo; | |
766 | int err; | |
767 | ||
768 | lock_kernel(); | |
769 | ||
770 | err = fat_dir_empty(inode); | |
771 | if (err) | |
772 | goto out; | |
773 | err = vfat_find(dir, &dentry->d_name, &sinfo); | |
774 | if (err) | |
775 | goto out; | |
776 | ||
777 | err = fat_remove_entries(dir, &sinfo); /* and releases bh */ | |
778 | if (err) | |
779 | goto out; | |
9a53c3a7 | 780 | drop_nlink(dir); |
1da177e4 | 781 | |
ce71ec36 | 782 | clear_nlink(inode); |
1da177e4 LT |
783 | inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC; |
784 | fat_detach(inode); | |
785 | out: | |
786 | unlock_kernel(); | |
787 | ||
788 | return err; | |
789 | } | |
790 | ||
791 | static int vfat_unlink(struct inode *dir, struct dentry *dentry) | |
792 | { | |
793 | struct inode *inode = dentry->d_inode; | |
794 | struct fat_slot_info sinfo; | |
795 | int err; | |
796 | ||
797 | lock_kernel(); | |
798 | ||
799 | err = vfat_find(dir, &dentry->d_name, &sinfo); | |
800 | if (err) | |
801 | goto out; | |
802 | ||
803 | err = fat_remove_entries(dir, &sinfo); /* and releases bh */ | |
804 | if (err) | |
805 | goto out; | |
ce71ec36 | 806 | clear_nlink(inode); |
1da177e4 LT |
807 | inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC; |
808 | fat_detach(inode); | |
809 | out: | |
810 | unlock_kernel(); | |
811 | ||
812 | return err; | |
813 | } | |
814 | ||
815 | static int vfat_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
816 | { | |
817 | struct super_block *sb = dir->i_sb; | |
818 | struct inode *inode; | |
819 | struct fat_slot_info sinfo; | |
820 | struct timespec ts; | |
821 | int err, cluster; | |
822 | ||
823 | lock_kernel(); | |
824 | ||
825 | ts = CURRENT_TIME_SEC; | |
826 | cluster = fat_alloc_new_dir(dir, &ts); | |
827 | if (cluster < 0) { | |
828 | err = cluster; | |
829 | goto out; | |
830 | } | |
831 | err = vfat_add_entry(dir, &dentry->d_name, 1, cluster, &ts, &sinfo); | |
832 | if (err) | |
833 | goto out_free; | |
834 | dir->i_version++; | |
d8c76e6f | 835 | inc_nlink(dir); |
1da177e4 LT |
836 | |
837 | inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); | |
838 | brelse(sinfo.bh); | |
839 | if (IS_ERR(inode)) { | |
840 | err = PTR_ERR(inode); | |
841 | /* the directory was completed, just return a error */ | |
842 | goto out; | |
843 | } | |
844 | inode->i_version++; | |
845 | inode->i_nlink = 2; | |
846 | inode->i_mtime = inode->i_atime = inode->i_ctime = ts; | |
847 | /* timestamp is already written, so mark_inode_dirty() is unneeded. */ | |
848 | ||
849 | dentry->d_time = dentry->d_parent->d_inode->i_version; | |
850 | d_instantiate(dentry, inode); | |
851 | ||
852 | unlock_kernel(); | |
853 | return 0; | |
854 | ||
855 | out_free: | |
856 | fat_free_clusters(dir, cluster); | |
857 | out: | |
858 | unlock_kernel(); | |
859 | return err; | |
860 | } | |
861 | ||
862 | static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry, | |
863 | struct inode *new_dir, struct dentry *new_dentry) | |
864 | { | |
865 | struct buffer_head *dotdot_bh; | |
866 | struct msdos_dir_entry *dotdot_de; | |
1da177e4 LT |
867 | struct inode *old_inode, *new_inode; |
868 | struct fat_slot_info old_sinfo, sinfo; | |
869 | struct timespec ts; | |
9131dd42 | 870 | loff_t dotdot_i_pos, new_i_pos; |
1da177e4 LT |
871 | int err, is_dir, update_dotdot, corrupt = 0; |
872 | ||
873 | old_sinfo.bh = sinfo.bh = dotdot_bh = NULL; | |
874 | old_inode = old_dentry->d_inode; | |
875 | new_inode = new_dentry->d_inode; | |
876 | lock_kernel(); | |
877 | err = vfat_find(old_dir, &old_dentry->d_name, &old_sinfo); | |
878 | if (err) | |
879 | goto out; | |
880 | ||
881 | is_dir = S_ISDIR(old_inode->i_mode); | |
882 | update_dotdot = (is_dir && old_dir != new_dir); | |
883 | if (update_dotdot) { | |
884 | if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de, | |
885 | &dotdot_i_pos) < 0) { | |
886 | err = -EIO; | |
887 | goto out; | |
888 | } | |
889 | } | |
890 | ||
891 | ts = CURRENT_TIME_SEC; | |
892 | if (new_inode) { | |
1da177e4 LT |
893 | if (is_dir) { |
894 | err = fat_dir_empty(new_inode); | |
895 | if (err) | |
896 | goto out; | |
897 | } | |
9131dd42 | 898 | new_i_pos = MSDOS_I(new_inode)->i_pos; |
1da177e4 LT |
899 | fat_detach(new_inode); |
900 | } else { | |
901 | err = vfat_add_entry(new_dir, &new_dentry->d_name, is_dir, 0, | |
902 | &ts, &sinfo); | |
903 | if (err) | |
904 | goto out; | |
9131dd42 | 905 | new_i_pos = sinfo.i_pos; |
1da177e4 LT |
906 | } |
907 | new_dir->i_version++; | |
908 | ||
909 | fat_detach(old_inode); | |
9131dd42 | 910 | fat_attach(old_inode, new_i_pos); |
1da177e4 LT |
911 | if (IS_DIRSYNC(new_dir)) { |
912 | err = fat_sync_inode(old_inode); | |
913 | if (err) | |
914 | goto error_inode; | |
915 | } else | |
916 | mark_inode_dirty(old_inode); | |
917 | ||
918 | if (update_dotdot) { | |
919 | int start = MSDOS_I(new_dir)->i_logstart; | |
920 | dotdot_de->start = cpu_to_le16(start); | |
921 | dotdot_de->starthi = cpu_to_le16(start >> 16); | |
922 | mark_buffer_dirty(dotdot_bh); | |
923 | if (IS_DIRSYNC(new_dir)) { | |
924 | err = sync_dirty_buffer(dotdot_bh); | |
925 | if (err) | |
926 | goto error_dotdot; | |
927 | } | |
9a53c3a7 | 928 | drop_nlink(old_dir); |
1da177e4 | 929 | if (!new_inode) |
d8c76e6f | 930 | inc_nlink(new_dir); |
1da177e4 LT |
931 | } |
932 | ||
933 | err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */ | |
934 | old_sinfo.bh = NULL; | |
935 | if (err) | |
936 | goto error_dotdot; | |
937 | old_dir->i_version++; | |
938 | old_dir->i_ctime = old_dir->i_mtime = ts; | |
939 | if (IS_DIRSYNC(old_dir)) | |
940 | (void)fat_sync_inode(old_dir); | |
941 | else | |
942 | mark_inode_dirty(old_dir); | |
943 | ||
944 | if (new_inode) { | |
9a53c3a7 | 945 | drop_nlink(new_inode); |
1da177e4 | 946 | if (is_dir) |
9a53c3a7 | 947 | drop_nlink(new_inode); |
1da177e4 LT |
948 | new_inode->i_ctime = ts; |
949 | } | |
950 | out: | |
951 | brelse(sinfo.bh); | |
952 | brelse(dotdot_bh); | |
953 | brelse(old_sinfo.bh); | |
954 | unlock_kernel(); | |
955 | ||
956 | return err; | |
957 | ||
958 | error_dotdot: | |
959 | /* data cluster is shared, serious corruption */ | |
960 | corrupt = 1; | |
961 | ||
962 | if (update_dotdot) { | |
963 | int start = MSDOS_I(old_dir)->i_logstart; | |
964 | dotdot_de->start = cpu_to_le16(start); | |
965 | dotdot_de->starthi = cpu_to_le16(start >> 16); | |
966 | mark_buffer_dirty(dotdot_bh); | |
967 | corrupt |= sync_dirty_buffer(dotdot_bh); | |
968 | } | |
969 | error_inode: | |
970 | fat_detach(old_inode); | |
971 | fat_attach(old_inode, old_sinfo.i_pos); | |
972 | if (new_inode) { | |
9131dd42 | 973 | fat_attach(new_inode, new_i_pos); |
1da177e4 LT |
974 | if (corrupt) |
975 | corrupt |= fat_sync_inode(new_inode); | |
976 | } else { | |
977 | /* | |
978 | * If new entry was not sharing the data cluster, it | |
979 | * shouldn't be serious corruption. | |
980 | */ | |
981 | int err2 = fat_remove_entries(new_dir, &sinfo); | |
982 | if (corrupt) | |
983 | corrupt |= err2; | |
984 | sinfo.bh = NULL; | |
985 | } | |
986 | if (corrupt < 0) { | |
987 | fat_fs_panic(new_dir->i_sb, | |
988 | "%s: Filesystem corrupted (i_pos %lld)", | |
8e24eea7 | 989 | __func__, sinfo.i_pos); |
1da177e4 LT |
990 | } |
991 | goto out; | |
992 | } | |
993 | ||
c5ef1c42 | 994 | static const struct inode_operations vfat_dir_inode_operations = { |
1da177e4 LT |
995 | .create = vfat_create, |
996 | .lookup = vfat_lookup, | |
997 | .unlink = vfat_unlink, | |
998 | .mkdir = vfat_mkdir, | |
999 | .rmdir = vfat_rmdir, | |
1000 | .rename = vfat_rename, | |
1278fdd3 | 1001 | .setattr = fat_setattr, |
da63fc7c | 1002 | .getattr = fat_getattr, |
1da177e4 LT |
1003 | }; |
1004 | ||
1005 | static int vfat_fill_super(struct super_block *sb, void *data, int silent) | |
1006 | { | |
1007 | int res; | |
1008 | ||
1009 | res = fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, 1); | |
1010 | if (res) | |
1011 | return res; | |
1012 | ||
1013 | if (MSDOS_SB(sb)->options.name_check != 's') | |
1014 | sb->s_root->d_op = &vfat_dentry_ops[0]; | |
1015 | else | |
1016 | sb->s_root->d_op = &vfat_dentry_ops[2]; | |
1017 | ||
1018 | return 0; | |
1019 | } | |
1020 | ||
454e2398 DH |
1021 | static int vfat_get_sb(struct file_system_type *fs_type, |
1022 | int flags, const char *dev_name, | |
1023 | void *data, struct vfsmount *mnt) | |
1da177e4 | 1024 | { |
454e2398 DH |
1025 | return get_sb_bdev(fs_type, flags, dev_name, data, vfat_fill_super, |
1026 | mnt); | |
1da177e4 LT |
1027 | } |
1028 | ||
1029 | static struct file_system_type vfat_fs_type = { | |
1030 | .owner = THIS_MODULE, | |
1031 | .name = "vfat", | |
1032 | .get_sb = vfat_get_sb, | |
1033 | .kill_sb = kill_block_super, | |
1034 | .fs_flags = FS_REQUIRES_DEV, | |
1035 | }; | |
1036 | ||
1037 | static int __init init_vfat_fs(void) | |
1038 | { | |
1039 | return register_filesystem(&vfat_fs_type); | |
1040 | } | |
1041 | ||
1042 | static void __exit exit_vfat_fs(void) | |
1043 | { | |
1044 | unregister_filesystem(&vfat_fs_type); | |
1045 | } | |
1046 | ||
1047 | MODULE_LICENSE("GPL"); | |
1048 | MODULE_DESCRIPTION("VFAT filesystem support"); | |
1049 | MODULE_AUTHOR("Gordon Chaffee"); | |
1050 | ||
1051 | module_init(init_vfat_fs) | |
1052 | module_exit(exit_vfat_fs) |