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> | |
1da177e4 | 19 | #include <linux/jiffies.h> |
1da177e4 LT |
20 | #include <linux/ctype.h> |
21 | #include <linux/slab.h> | |
1da177e4 LT |
22 | #include <linux/buffer_head.h> |
23 | #include <linux/namei.h> | |
9e975dae | 24 | #include "fat.h" |
1da177e4 | 25 | |
1b524672 OH |
26 | /* |
27 | * If new entry was created in the parent, it could create the 8.3 | |
28 | * alias (the shortname of logname). So, the parent may have the | |
29 | * negative-dentry which matches the created 8.3 alias. | |
30 | * | |
31 | * If it happened, the negative dentry isn't actually negative | |
32 | * anymore. So, drop it. | |
33 | */ | |
34 | static int vfat_revalidate_shortname(struct dentry *dentry) | |
1da177e4 LT |
35 | { |
36 | int ret = 1; | |
1b524672 OH |
37 | spin_lock(&dentry->d_lock); |
38 | if (dentry->d_time != dentry->d_parent->d_inode->i_version) | |
1da177e4 | 39 | ret = 0; |
1b524672 | 40 | spin_unlock(&dentry->d_lock); |
1da177e4 LT |
41 | return ret; |
42 | } | |
43 | ||
1b524672 OH |
44 | static int vfat_revalidate(struct dentry *dentry, struct nameidata *nd) |
45 | { | |
46 | /* This is not negative dentry. Always valid. */ | |
47 | if (dentry->d_inode) | |
48 | return 1; | |
49 | return vfat_revalidate_shortname(dentry); | |
50 | } | |
51 | ||
52 | static int vfat_revalidate_ci(struct dentry *dentry, struct nameidata *nd) | |
53 | { | |
54 | /* | |
55 | * This is not negative dentry. Always valid. | |
56 | * | |
57 | * Note, rename() to existing directory entry will have ->d_inode, | |
58 | * and will use existing name which isn't specified name by user. | |
59 | * | |
60 | * We may be able to drop this positive dentry here. But dropping | |
61 | * positive dentry isn't good idea. So it's unsupported like | |
62 | * rename("filename", "FILENAME") for now. | |
63 | */ | |
64 | if (dentry->d_inode) | |
65 | return 1; | |
66 | ||
67 | /* | |
68 | * This may be nfsd (or something), anyway, we can't see the | |
69 | * intent of this. So, since this can be for creation, drop it. | |
70 | */ | |
71 | if (!nd) | |
72 | return 0; | |
73 | ||
74 | /* | |
75 | * Drop the negative dentry, in order to make sure to use the | |
76 | * case sensitive name which is specified by user if this is | |
77 | * for creation. | |
78 | */ | |
79 | if (!(nd->flags & (LOOKUP_CONTINUE | LOOKUP_PARENT))) { | |
ebeb0406 | 80 | if (nd->flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET)) |
1b524672 OH |
81 | return 0; |
82 | } | |
83 | ||
84 | return vfat_revalidate_shortname(dentry); | |
85 | } | |
86 | ||
1da177e4 LT |
87 | /* returns the length of a struct qstr, ignoring trailing dots */ |
88 | static unsigned int vfat_striptail_len(struct qstr *qstr) | |
89 | { | |
90 | unsigned int len = qstr->len; | |
91 | ||
92 | while (len && qstr->name[len - 1] == '.') | |
93 | len--; | |
94 | return len; | |
95 | } | |
96 | ||
97 | /* | |
98 | * Compute the hash for the vfat name corresponding to the dentry. | |
99 | * Note: if the name is invalid, we leave the hash code unchanged so | |
100 | * that the existing dentry can be used. The vfat fs routines will | |
101 | * return ENOENT or EINVAL as appropriate. | |
102 | */ | |
103 | static int vfat_hash(struct dentry *dentry, struct qstr *qstr) | |
104 | { | |
105 | qstr->hash = full_name_hash(qstr->name, vfat_striptail_len(qstr)); | |
106 | return 0; | |
107 | } | |
108 | ||
109 | /* | |
110 | * Compute the hash for the vfat name corresponding to the dentry. | |
111 | * Note: if the name is invalid, we leave the hash code unchanged so | |
112 | * that the existing dentry can be used. The vfat fs routines will | |
113 | * return ENOENT or EINVAL as appropriate. | |
114 | */ | |
115 | static int vfat_hashi(struct dentry *dentry, struct qstr *qstr) | |
116 | { | |
117 | struct nls_table *t = MSDOS_SB(dentry->d_inode->i_sb)->nls_io; | |
118 | const unsigned char *name; | |
119 | unsigned int len; | |
120 | unsigned long hash; | |
121 | ||
122 | name = qstr->name; | |
123 | len = vfat_striptail_len(qstr); | |
124 | ||
125 | hash = init_name_hash(); | |
126 | while (len--) | |
127 | hash = partial_name_hash(nls_tolower(t, *name++), hash); | |
128 | qstr->hash = end_name_hash(hash); | |
129 | ||
130 | return 0; | |
131 | } | |
132 | ||
133 | /* | |
134 | * Case insensitive compare of two vfat names. | |
135 | */ | |
136 | static int vfat_cmpi(struct dentry *dentry, struct qstr *a, struct qstr *b) | |
137 | { | |
138 | struct nls_table *t = MSDOS_SB(dentry->d_inode->i_sb)->nls_io; | |
139 | unsigned int alen, blen; | |
140 | ||
141 | /* A filename cannot end in '.' or we treat it like it has none */ | |
142 | alen = vfat_striptail_len(a); | |
143 | blen = vfat_striptail_len(b); | |
144 | if (alen == blen) { | |
145 | if (nls_strnicmp(t, a->name, b->name, alen) == 0) | |
146 | return 0; | |
147 | } | |
148 | return 1; | |
149 | } | |
150 | ||
151 | /* | |
152 | * Case sensitive compare of two vfat names. | |
153 | */ | |
154 | static int vfat_cmp(struct dentry *dentry, struct qstr *a, struct qstr *b) | |
155 | { | |
156 | unsigned int alen, blen; | |
157 | ||
158 | /* A filename cannot end in '.' or we treat it like it has none */ | |
159 | alen = vfat_striptail_len(a); | |
160 | blen = vfat_striptail_len(b); | |
161 | if (alen == blen) { | |
162 | if (strncmp(a->name, b->name, alen) == 0) | |
163 | return 0; | |
164 | } | |
165 | return 1; | |
166 | } | |
167 | ||
ce6cdc47 | 168 | static const struct dentry_operations vfat_ci_dentry_ops = { |
1b524672 OH |
169 | .d_revalidate = vfat_revalidate_ci, |
170 | .d_hash = vfat_hashi, | |
171 | .d_compare = vfat_cmpi, | |
172 | }; | |
173 | ||
ce6cdc47 | 174 | static const struct dentry_operations vfat_dentry_ops = { |
1b524672 OH |
175 | .d_revalidate = vfat_revalidate, |
176 | .d_hash = vfat_hash, | |
177 | .d_compare = vfat_cmp, | |
1da177e4 LT |
178 | }; |
179 | ||
180 | /* Characters that are undesirable in an MS-DOS file name */ | |
181 | ||
182 | static inline wchar_t vfat_bad_char(wchar_t w) | |
183 | { | |
184 | return (w < 0x0020) | |
185 | || (w == '*') || (w == '?') || (w == '<') || (w == '>') | |
186 | || (w == '|') || (w == '"') || (w == ':') || (w == '/') | |
187 | || (w == '\\'); | |
188 | } | |
189 | ||
190 | static inline wchar_t vfat_replace_char(wchar_t w) | |
191 | { | |
192 | return (w == '[') || (w == ']') || (w == ';') || (w == ',') | |
193 | || (w == '+') || (w == '='); | |
194 | } | |
195 | ||
196 | static wchar_t vfat_skip_char(wchar_t w) | |
197 | { | |
198 | return (w == '.') || (w == ' '); | |
199 | } | |
200 | ||
201 | static inline int vfat_is_used_badchars(const wchar_t *s, int len) | |
202 | { | |
203 | int i; | |
204 | ||
205 | for (i = 0; i < len; i++) | |
206 | if (vfat_bad_char(s[i])) | |
207 | return -EINVAL; | |
1da177e4 | 208 | |
f22032ba | 209 | if (s[i - 1] == ' ') /* last character cannot be space */ |
1da177e4 | 210 | return -EINVAL; |
f22032ba | 211 | |
1da177e4 LT |
212 | return 0; |
213 | } | |
214 | ||
215 | static int vfat_find_form(struct inode *dir, unsigned char *name) | |
216 | { | |
217 | struct fat_slot_info sinfo; | |
218 | int err = fat_scan(dir, name, &sinfo); | |
219 | if (err) | |
220 | return -ENOENT; | |
221 | brelse(sinfo.bh); | |
222 | return 0; | |
223 | } | |
224 | ||
225 | /* | |
226 | * 1) Valid characters for the 8.3 format alias are any combination of | |
227 | * letters, uppercase alphabets, digits, any of the | |
228 | * following special characters: | |
229 | * $ % ' ` - @ { } ~ ! # ( ) & _ ^ | |
230 | * In this case Longfilename is not stored in disk. | |
231 | * | |
232 | * WinNT's Extension: | |
233 | * File name and extension name is contain uppercase/lowercase | |
234 | * only. And it is expressed by CASE_LOWER_BASE and CASE_LOWER_EXT. | |
235 | * | |
236 | * 2) File name is 8.3 format, but it contain the uppercase and | |
237 | * lowercase char, muliti bytes char, etc. In this case numtail is not | |
238 | * added, but Longfilename is stored. | |
239 | * | |
240 | * 3) When the one except for the above, or the following special | |
241 | * character are contained: | |
242 | * . [ ] ; , + = | |
243 | * numtail is added, and Longfilename must be stored in disk . | |
244 | */ | |
245 | struct shortname_info { | |
246 | unsigned char lower:1, | |
247 | upper:1, | |
248 | valid:1; | |
249 | }; | |
250 | #define INIT_SHORTNAME_INFO(x) do { \ | |
251 | (x)->lower = 1; \ | |
252 | (x)->upper = 1; \ | |
253 | (x)->valid = 1; \ | |
254 | } while (0) | |
255 | ||
256 | static inline int to_shortname_char(struct nls_table *nls, | |
257 | unsigned char *buf, int buf_size, | |
258 | wchar_t *src, struct shortname_info *info) | |
259 | { | |
260 | int len; | |
261 | ||
262 | if (vfat_skip_char(*src)) { | |
263 | info->valid = 0; | |
264 | return 0; | |
265 | } | |
266 | if (vfat_replace_char(*src)) { | |
267 | info->valid = 0; | |
268 | buf[0] = '_'; | |
269 | return 1; | |
270 | } | |
271 | ||
272 | len = nls->uni2char(*src, buf, buf_size); | |
273 | if (len <= 0) { | |
274 | info->valid = 0; | |
275 | buf[0] = '_'; | |
276 | len = 1; | |
277 | } else if (len == 1) { | |
278 | unsigned char prev = buf[0]; | |
279 | ||
280 | if (buf[0] >= 0x7F) { | |
281 | info->lower = 0; | |
282 | info->upper = 0; | |
283 | } | |
284 | ||
285 | buf[0] = nls_toupper(nls, buf[0]); | |
286 | if (isalpha(buf[0])) { | |
287 | if (buf[0] == prev) | |
288 | info->lower = 0; | |
289 | else | |
290 | info->upper = 0; | |
291 | } | |
292 | } else { | |
293 | info->lower = 0; | |
294 | info->upper = 0; | |
295 | } | |
296 | ||
297 | return len; | |
298 | } | |
299 | ||
300 | /* | |
301 | * Given a valid longname, create a unique shortname. Make sure the | |
302 | * shortname does not exist | |
303 | * Returns negative number on error, 0 for a normal | |
304 | * return, and 1 for valid shortname | |
305 | */ | |
306 | static int vfat_create_shortname(struct inode *dir, struct nls_table *nls, | |
307 | wchar_t *uname, int ulen, | |
308 | unsigned char *name_res, unsigned char *lcase) | |
309 | { | |
310 | struct fat_mount_options *opts = &MSDOS_SB(dir->i_sb)->options; | |
311 | wchar_t *ip, *ext_start, *end, *name_start; | |
312 | unsigned char base[9], ext[4], buf[8], *p; | |
313 | unsigned char charbuf[NLS_MAX_CHARSET_SIZE]; | |
314 | int chl, chi; | |
315 | int sz = 0, extlen, baselen, i, numtail_baselen, numtail2_baselen; | |
316 | int is_shortname; | |
317 | struct shortname_info base_info, ext_info; | |
318 | ||
319 | is_shortname = 1; | |
320 | INIT_SHORTNAME_INFO(&base_info); | |
321 | INIT_SHORTNAME_INFO(&ext_info); | |
322 | ||
323 | /* Now, we need to create a shortname from the long name */ | |
324 | ext_start = end = &uname[ulen]; | |
325 | while (--ext_start >= uname) { | |
326 | if (*ext_start == 0x002E) { /* is `.' */ | |
327 | if (ext_start == end - 1) { | |
328 | sz = ulen; | |
329 | ext_start = NULL; | |
330 | } | |
331 | break; | |
332 | } | |
333 | } | |
334 | ||
335 | if (ext_start == uname - 1) { | |
336 | sz = ulen; | |
337 | ext_start = NULL; | |
338 | } else if (ext_start) { | |
339 | /* | |
340 | * Names which start with a dot could be just | |
341 | * an extension eg. "...test". In this case Win95 | |
342 | * uses the extension as the name and sets no extension. | |
343 | */ | |
344 | name_start = &uname[0]; | |
345 | while (name_start < ext_start) { | |
346 | if (!vfat_skip_char(*name_start)) | |
347 | break; | |
348 | name_start++; | |
349 | } | |
350 | if (name_start != ext_start) { | |
351 | sz = ext_start - uname; | |
352 | ext_start++; | |
353 | } else { | |
354 | sz = ulen; | |
355 | ext_start = NULL; | |
356 | } | |
357 | } | |
358 | ||
359 | numtail_baselen = 6; | |
360 | numtail2_baselen = 2; | |
361 | for (baselen = i = 0, p = base, ip = uname; i < sz; i++, ip++) { | |
362 | chl = to_shortname_char(nls, charbuf, sizeof(charbuf), | |
363 | ip, &base_info); | |
364 | if (chl == 0) | |
365 | continue; | |
366 | ||
367 | if (baselen < 2 && (baselen + chl) > 2) | |
368 | numtail2_baselen = baselen; | |
369 | if (baselen < 6 && (baselen + chl) > 6) | |
370 | numtail_baselen = baselen; | |
371 | for (chi = 0; chi < chl; chi++) { | |
372 | *p++ = charbuf[chi]; | |
373 | baselen++; | |
374 | if (baselen >= 8) | |
375 | break; | |
376 | } | |
377 | if (baselen >= 8) { | |
378 | if ((chi < chl - 1) || (ip + 1) - uname < sz) | |
379 | is_shortname = 0; | |
380 | break; | |
381 | } | |
382 | } | |
383 | if (baselen == 0) { | |
384 | return -EINVAL; | |
385 | } | |
386 | ||
387 | extlen = 0; | |
388 | if (ext_start) { | |
389 | for (p = ext, ip = ext_start; extlen < 3 && ip < end; ip++) { | |
390 | chl = to_shortname_char(nls, charbuf, sizeof(charbuf), | |
391 | ip, &ext_info); | |
392 | if (chl == 0) | |
393 | continue; | |
394 | ||
395 | if ((extlen + chl) > 3) { | |
396 | is_shortname = 0; | |
397 | break; | |
398 | } | |
399 | for (chi = 0; chi < chl; chi++) { | |
400 | *p++ = charbuf[chi]; | |
401 | extlen++; | |
402 | } | |
403 | if (extlen >= 3) { | |
404 | if (ip + 1 != end) | |
405 | is_shortname = 0; | |
406 | break; | |
407 | } | |
408 | } | |
409 | } | |
410 | ext[extlen] = '\0'; | |
411 | base[baselen] = '\0'; | |
412 | ||
413 | /* Yes, it can happen. ".\xe5" would do it. */ | |
414 | if (base[0] == DELETED_FLAG) | |
415 | base[0] = 0x05; | |
416 | ||
417 | /* OK, at this point we know that base is not longer than 8 symbols, | |
418 | * ext is not longer than 3, base is nonempty, both don't contain | |
419 | * any bad symbols (lowercase transformed to uppercase). | |
420 | */ | |
421 | ||
422 | memset(name_res, ' ', MSDOS_NAME); | |
423 | memcpy(name_res, base, baselen); | |
424 | memcpy(name_res + 8, ext, extlen); | |
425 | *lcase = 0; | |
426 | if (is_shortname && base_info.valid && ext_info.valid) { | |
427 | if (vfat_find_form(dir, name_res) == 0) | |
428 | return -EEXIST; | |
429 | ||
430 | if (opts->shortname & VFAT_SFN_CREATE_WIN95) { | |
431 | return (base_info.upper && ext_info.upper); | |
432 | } else if (opts->shortname & VFAT_SFN_CREATE_WINNT) { | |
433 | if ((base_info.upper || base_info.lower) && | |
434 | (ext_info.upper || ext_info.lower)) { | |
435 | if (!base_info.upper && base_info.lower) | |
436 | *lcase |= CASE_LOWER_BASE; | |
437 | if (!ext_info.upper && ext_info.lower) | |
438 | *lcase |= CASE_LOWER_EXT; | |
439 | return 1; | |
440 | } | |
441 | return 0; | |
442 | } else { | |
443 | BUG(); | |
444 | } | |
445 | } | |
446 | ||
447 | if (opts->numtail == 0) | |
448 | if (vfat_find_form(dir, name_res) < 0) | |
449 | return 0; | |
450 | ||
451 | /* | |
452 | * Try to find a unique extension. This used to | |
453 | * iterate through all possibilities sequentially, | |
454 | * but that gave extremely bad performance. Windows | |
455 | * only tries a few cases before using random | |
456 | * values for part of the base. | |
457 | */ | |
458 | ||
459 | if (baselen > 6) { | |
460 | baselen = numtail_baselen; | |
461 | name_res[7] = ' '; | |
462 | } | |
463 | name_res[baselen] = '~'; | |
464 | for (i = 1; i < 10; i++) { | |
465 | name_res[baselen + 1] = i + '0'; | |
466 | if (vfat_find_form(dir, name_res) < 0) | |
467 | return 0; | |
468 | } | |
469 | ||
470 | i = jiffies & 0xffff; | |
471 | sz = (jiffies >> 16) & 0x7; | |
472 | if (baselen > 2) { | |
473 | baselen = numtail2_baselen; | |
474 | name_res[7] = ' '; | |
475 | } | |
476 | name_res[baselen + 4] = '~'; | |
477 | name_res[baselen + 5] = '1' + sz; | |
478 | while (1) { | |
479 | sprintf(buf, "%04X", i); | |
480 | memcpy(&name_res[baselen], buf, 4); | |
481 | if (vfat_find_form(dir, name_res) < 0) | |
482 | break; | |
483 | i -= 11; | |
484 | } | |
485 | return 0; | |
486 | } | |
487 | ||
488 | /* Translate a string, including coded sequences into Unicode */ | |
489 | static int | |
490 | xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, | |
491 | int *longlen, int *outlen, int escape, int utf8, | |
492 | struct nls_table *nls) | |
493 | { | |
494 | const unsigned char *ip; | |
495 | unsigned char nc; | |
496 | unsigned char *op; | |
497 | unsigned int ec; | |
498 | int i, k, fill; | |
499 | int charlen; | |
500 | ||
501 | if (utf8) { | |
502 | int name_len = strlen(name); | |
503 | ||
74675a58 | 504 | *outlen = utf8s_to_utf16s(name, PATH_MAX, (wchar_t *) outname); |
1da177e4 LT |
505 | |
506 | /* | |
507 | * We stripped '.'s before and set len appropriately, | |
74675a58 | 508 | * but utf8s_to_utf16s doesn't care about len |
1da177e4 LT |
509 | */ |
510 | *outlen -= (name_len - len); | |
511 | ||
f22032ba KM |
512 | if (*outlen > 255) |
513 | return -ENAMETOOLONG; | |
514 | ||
1da177e4 LT |
515 | op = &outname[*outlen * sizeof(wchar_t)]; |
516 | } else { | |
517 | if (nls) { | |
518 | for (i = 0, ip = name, op = outname, *outlen = 0; | |
f22032ba | 519 | i < len && *outlen <= 255; |
1da177e4 LT |
520 | *outlen += 1) |
521 | { | |
522 | if (escape && (*ip == ':')) { | |
523 | if (i > len - 5) | |
524 | return -EINVAL; | |
525 | ec = 0; | |
526 | for (k = 1; k < 5; k++) { | |
527 | nc = ip[k]; | |
528 | ec <<= 4; | |
529 | if (nc >= '0' && nc <= '9') { | |
530 | ec |= nc - '0'; | |
531 | continue; | |
532 | } | |
533 | if (nc >= 'a' && nc <= 'f') { | |
534 | ec |= nc - ('a' - 10); | |
535 | continue; | |
536 | } | |
537 | if (nc >= 'A' && nc <= 'F') { | |
538 | ec |= nc - ('A' - 10); | |
539 | continue; | |
540 | } | |
541 | return -EINVAL; | |
542 | } | |
543 | *op++ = ec & 0xFF; | |
544 | *op++ = ec >> 8; | |
545 | ip += 5; | |
546 | i += 5; | |
547 | } else { | |
548 | if ((charlen = nls->char2uni(ip, len - i, (wchar_t *)op)) < 0) | |
549 | return -EINVAL; | |
550 | ip += charlen; | |
551 | i += charlen; | |
552 | op += 2; | |
553 | } | |
554 | } | |
f22032ba KM |
555 | if (i < len) |
556 | return -ENAMETOOLONG; | |
1da177e4 LT |
557 | } else { |
558 | for (i = 0, ip = name, op = outname, *outlen = 0; | |
f22032ba | 559 | i < len && *outlen <= 255; |
1da177e4 LT |
560 | i++, *outlen += 1) |
561 | { | |
562 | *op++ = *ip++; | |
563 | *op++ = 0; | |
564 | } | |
f22032ba KM |
565 | if (i < len) |
566 | return -ENAMETOOLONG; | |
1da177e4 LT |
567 | } |
568 | } | |
1da177e4 LT |
569 | |
570 | *longlen = *outlen; | |
571 | if (*outlen % 13) { | |
572 | *op++ = 0; | |
573 | *op++ = 0; | |
574 | *outlen += 1; | |
575 | if (*outlen % 13) { | |
576 | fill = 13 - (*outlen % 13); | |
577 | for (i = 0; i < fill; i++) { | |
578 | *op++ = 0xff; | |
579 | *op++ = 0xff; | |
580 | } | |
581 | *outlen += fill; | |
582 | } | |
583 | } | |
584 | ||
585 | return 0; | |
586 | } | |
587 | ||
588 | static int vfat_build_slots(struct inode *dir, const unsigned char *name, | |
589 | int len, int is_dir, int cluster, | |
590 | struct timespec *ts, | |
591 | struct msdos_dir_slot *slots, int *nr_slots) | |
592 | { | |
593 | struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb); | |
594 | struct fat_mount_options *opts = &sbi->options; | |
595 | struct msdos_dir_slot *ps; | |
596 | struct msdos_dir_entry *de; | |
1da177e4 LT |
597 | unsigned char cksum, lcase; |
598 | unsigned char msdos_name[MSDOS_NAME]; | |
599 | wchar_t *uname; | |
600 | __le16 time, date; | |
7decd1cb | 601 | u8 time_cs; |
1da177e4 LT |
602 | int err, ulen, usize, i; |
603 | loff_t offset; | |
604 | ||
605 | *nr_slots = 0; | |
1da177e4 | 606 | |
c7a6c4ed OH |
607 | uname = __getname(); |
608 | if (!uname) | |
1da177e4 LT |
609 | return -ENOMEM; |
610 | ||
1da177e4 LT |
611 | err = xlate_to_uni(name, len, (unsigned char *)uname, &ulen, &usize, |
612 | opts->unicode_xlate, opts->utf8, sbi->nls_io); | |
613 | if (err) | |
614 | goto out_free; | |
615 | ||
616 | err = vfat_is_used_badchars(uname, ulen); | |
617 | if (err) | |
618 | goto out_free; | |
619 | ||
620 | err = vfat_create_shortname(dir, sbi->nls_disk, uname, ulen, | |
621 | msdos_name, &lcase); | |
622 | if (err < 0) | |
623 | goto out_free; | |
624 | else if (err == 1) { | |
625 | de = (struct msdos_dir_entry *)slots; | |
626 | err = 0; | |
627 | goto shortname; | |
628 | } | |
629 | ||
630 | /* build the entry of long file name */ | |
451cbaa1 | 631 | cksum = fat_checksum(msdos_name); |
1da177e4 LT |
632 | |
633 | *nr_slots = usize / 13; | |
634 | for (ps = slots, i = *nr_slots; i > 0; i--, ps++) { | |
635 | ps->id = i; | |
636 | ps->attr = ATTR_EXT; | |
637 | ps->reserved = 0; | |
638 | ps->alias_checksum = cksum; | |
639 | ps->start = 0; | |
640 | offset = (i - 1) * 13; | |
641 | fatwchar_to16(ps->name0_4, uname + offset, 5); | |
642 | fatwchar_to16(ps->name5_10, uname + offset + 5, 6); | |
643 | fatwchar_to16(ps->name11_12, uname + offset + 11, 2); | |
644 | } | |
645 | slots[0].id |= 0x40; | |
646 | de = (struct msdos_dir_entry *)ps; | |
647 | ||
648 | shortname: | |
649 | /* build the entry of 8.3 alias name */ | |
650 | (*nr_slots)++; | |
651 | memcpy(de->name, msdos_name, MSDOS_NAME); | |
652 | de->attr = is_dir ? ATTR_DIR : ATTR_ARCH; | |
653 | de->lcase = lcase; | |
7decd1cb | 654 | fat_time_unix2fat(sbi, ts, &time, &date, &time_cs); |
1da177e4 LT |
655 | de->time = de->ctime = time; |
656 | de->date = de->cdate = de->adate = date; | |
7decd1cb | 657 | de->ctime_cs = time_cs; |
1da177e4 LT |
658 | de->start = cpu_to_le16(cluster); |
659 | de->starthi = cpu_to_le16(cluster >> 16); | |
660 | de->size = 0; | |
661 | out_free: | |
c7a6c4ed | 662 | __putname(uname); |
1da177e4 LT |
663 | return err; |
664 | } | |
665 | ||
666 | static int vfat_add_entry(struct inode *dir, struct qstr *qname, int is_dir, | |
667 | int cluster, struct timespec *ts, | |
668 | struct fat_slot_info *sinfo) | |
669 | { | |
670 | struct msdos_dir_slot *slots; | |
671 | unsigned int len; | |
672 | int err, nr_slots; | |
673 | ||
674 | len = vfat_striptail_len(qname); | |
675 | if (len == 0) | |
676 | return -ENOENT; | |
677 | ||
8f593427 | 678 | slots = kmalloc(sizeof(*slots) * MSDOS_SLOTS, GFP_NOFS); |
1da177e4 LT |
679 | if (slots == NULL) |
680 | return -ENOMEM; | |
681 | ||
682 | err = vfat_build_slots(dir, qname->name, len, is_dir, cluster, ts, | |
683 | slots, &nr_slots); | |
684 | if (err) | |
685 | goto cleanup; | |
686 | ||
687 | err = fat_add_entries(dir, slots, nr_slots, sinfo); | |
688 | if (err) | |
689 | goto cleanup; | |
690 | ||
691 | /* update timestamp */ | |
692 | dir->i_ctime = dir->i_mtime = dir->i_atime = *ts; | |
693 | if (IS_DIRSYNC(dir)) | |
694 | (void)fat_sync_inode(dir); | |
695 | else | |
696 | mark_inode_dirty(dir); | |
697 | cleanup: | |
698 | kfree(slots); | |
699 | return err; | |
700 | } | |
701 | ||
702 | static int vfat_find(struct inode *dir, struct qstr *qname, | |
703 | struct fat_slot_info *sinfo) | |
704 | { | |
705 | unsigned int len = vfat_striptail_len(qname); | |
706 | if (len == 0) | |
707 | return -ENOENT; | |
708 | return fat_search_long(dir, qname->name, len, sinfo); | |
709 | } | |
710 | ||
711 | static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, | |
712 | struct nameidata *nd) | |
713 | { | |
714 | struct super_block *sb = dir->i_sb; | |
715 | struct fat_slot_info sinfo; | |
068f5ae0 | 716 | struct inode *inode; |
1da177e4 | 717 | struct dentry *alias; |
1b524672 | 718 | int err; |
1da177e4 | 719 | |
8f593427 | 720 | lock_super(sb); |
1da177e4 LT |
721 | |
722 | err = vfat_find(dir, &dentry->d_name, &sinfo); | |
723 | if (err) { | |
068f5ae0 | 724 | if (err == -ENOENT) { |
068f5ae0 OH |
725 | inode = NULL; |
726 | goto out; | |
727 | } | |
1da177e4 LT |
728 | goto error; |
729 | } | |
1b524672 | 730 | |
1da177e4 LT |
731 | inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); |
732 | brelse(sinfo.bh); | |
733 | if (IS_ERR(inode)) { | |
068f5ae0 OH |
734 | err = PTR_ERR(inode); |
735 | goto error; | |
1da177e4 | 736 | } |
1b524672 | 737 | |
1da177e4 | 738 | alias = d_find_alias(inode); |
1b524672 OH |
739 | if (alias && !(alias->d_flags & DCACHE_DISCONNECTED)) { |
740 | /* | |
741 | * This inode has non DCACHE_DISCONNECTED dentry. This | |
742 | * means, the user did ->lookup() by an another name | |
743 | * (longname vs 8.3 alias of it) in past. | |
744 | * | |
745 | * Switch to new one for reason of locality if possible. | |
746 | */ | |
1c13a243 OH |
747 | BUG_ON(d_unhashed(alias)); |
748 | if (!S_ISDIR(inode->i_mode)) | |
749 | d_move(alias, dentry); | |
750 | iput(inode); | |
751 | unlock_super(sb); | |
752 | return alias; | |
1da177e4 | 753 | } |
068f5ae0 | 754 | out: |
8f593427 | 755 | unlock_super(sb); |
1b524672 | 756 | dentry->d_op = sb->s_root->d_op; |
1da177e4 LT |
757 | dentry->d_time = dentry->d_parent->d_inode->i_version; |
758 | dentry = d_splice_alias(inode, dentry); | |
759 | if (dentry) { | |
1b524672 | 760 | dentry->d_op = sb->s_root->d_op; |
1da177e4 LT |
761 | dentry->d_time = dentry->d_parent->d_inode->i_version; |
762 | } | |
763 | return dentry; | |
068f5ae0 OH |
764 | |
765 | error: | |
766 | unlock_super(sb); | |
767 | return ERR_PTR(err); | |
1da177e4 LT |
768 | } |
769 | ||
770 | static int vfat_create(struct inode *dir, struct dentry *dentry, int mode, | |
771 | struct nameidata *nd) | |
772 | { | |
773 | struct super_block *sb = dir->i_sb; | |
774 | struct inode *inode; | |
775 | struct fat_slot_info sinfo; | |
776 | struct timespec ts; | |
777 | int err; | |
778 | ||
8f593427 | 779 | lock_super(sb); |
1da177e4 LT |
780 | |
781 | ts = CURRENT_TIME_SEC; | |
782 | err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &ts, &sinfo); | |
783 | if (err) | |
784 | goto out; | |
785 | dir->i_version++; | |
786 | ||
787 | inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); | |
788 | brelse(sinfo.bh); | |
789 | if (IS_ERR(inode)) { | |
790 | err = PTR_ERR(inode); | |
791 | goto out; | |
792 | } | |
793 | inode->i_version++; | |
794 | inode->i_mtime = inode->i_atime = inode->i_ctime = ts; | |
795 | /* timestamp is already written, so mark_inode_dirty() is unneeded. */ | |
796 | ||
797 | dentry->d_time = dentry->d_parent->d_inode->i_version; | |
798 | d_instantiate(dentry, inode); | |
799 | out: | |
8f593427 | 800 | unlock_super(sb); |
1da177e4 LT |
801 | return err; |
802 | } | |
803 | ||
804 | static int vfat_rmdir(struct inode *dir, struct dentry *dentry) | |
805 | { | |
806 | struct inode *inode = dentry->d_inode; | |
8f593427 | 807 | struct super_block *sb = dir->i_sb; |
1da177e4 LT |
808 | struct fat_slot_info sinfo; |
809 | int err; | |
810 | ||
8f593427 | 811 | lock_super(sb); |
1da177e4 LT |
812 | |
813 | err = fat_dir_empty(inode); | |
814 | if (err) | |
815 | goto out; | |
816 | err = vfat_find(dir, &dentry->d_name, &sinfo); | |
817 | if (err) | |
818 | goto out; | |
819 | ||
820 | err = fat_remove_entries(dir, &sinfo); /* and releases bh */ | |
821 | if (err) | |
822 | goto out; | |
9a53c3a7 | 823 | drop_nlink(dir); |
1da177e4 | 824 | |
ce71ec36 | 825 | clear_nlink(inode); |
1da177e4 LT |
826 | inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC; |
827 | fat_detach(inode); | |
828 | out: | |
8f593427 | 829 | unlock_super(sb); |
1da177e4 LT |
830 | |
831 | return err; | |
832 | } | |
833 | ||
834 | static int vfat_unlink(struct inode *dir, struct dentry *dentry) | |
835 | { | |
836 | struct inode *inode = dentry->d_inode; | |
8f593427 | 837 | struct super_block *sb = dir->i_sb; |
1da177e4 LT |
838 | struct fat_slot_info sinfo; |
839 | int err; | |
840 | ||
8f593427 | 841 | lock_super(sb); |
1da177e4 LT |
842 | |
843 | err = vfat_find(dir, &dentry->d_name, &sinfo); | |
844 | if (err) | |
845 | goto out; | |
846 | ||
847 | err = fat_remove_entries(dir, &sinfo); /* and releases bh */ | |
848 | if (err) | |
849 | goto out; | |
ce71ec36 | 850 | clear_nlink(inode); |
1da177e4 LT |
851 | inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC; |
852 | fat_detach(inode); | |
853 | out: | |
8f593427 | 854 | unlock_super(sb); |
1da177e4 LT |
855 | |
856 | return err; | |
857 | } | |
858 | ||
859 | static int vfat_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
860 | { | |
861 | struct super_block *sb = dir->i_sb; | |
862 | struct inode *inode; | |
863 | struct fat_slot_info sinfo; | |
864 | struct timespec ts; | |
865 | int err, cluster; | |
866 | ||
8f593427 | 867 | lock_super(sb); |
1da177e4 LT |
868 | |
869 | ts = CURRENT_TIME_SEC; | |
870 | cluster = fat_alloc_new_dir(dir, &ts); | |
871 | if (cluster < 0) { | |
872 | err = cluster; | |
873 | goto out; | |
874 | } | |
875 | err = vfat_add_entry(dir, &dentry->d_name, 1, cluster, &ts, &sinfo); | |
876 | if (err) | |
877 | goto out_free; | |
878 | dir->i_version++; | |
d8c76e6f | 879 | inc_nlink(dir); |
1da177e4 LT |
880 | |
881 | inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); | |
882 | brelse(sinfo.bh); | |
883 | if (IS_ERR(inode)) { | |
884 | err = PTR_ERR(inode); | |
885 | /* the directory was completed, just return a error */ | |
886 | goto out; | |
887 | } | |
888 | inode->i_version++; | |
889 | inode->i_nlink = 2; | |
890 | inode->i_mtime = inode->i_atime = inode->i_ctime = ts; | |
891 | /* timestamp is already written, so mark_inode_dirty() is unneeded. */ | |
892 | ||
893 | dentry->d_time = dentry->d_parent->d_inode->i_version; | |
894 | d_instantiate(dentry, inode); | |
895 | ||
8f593427 | 896 | unlock_super(sb); |
1da177e4 LT |
897 | return 0; |
898 | ||
899 | out_free: | |
900 | fat_free_clusters(dir, cluster); | |
901 | out: | |
8f593427 | 902 | unlock_super(sb); |
1da177e4 LT |
903 | return err; |
904 | } | |
905 | ||
906 | static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry, | |
907 | struct inode *new_dir, struct dentry *new_dentry) | |
908 | { | |
909 | struct buffer_head *dotdot_bh; | |
910 | struct msdos_dir_entry *dotdot_de; | |
1da177e4 LT |
911 | struct inode *old_inode, *new_inode; |
912 | struct fat_slot_info old_sinfo, sinfo; | |
913 | struct timespec ts; | |
9131dd42 | 914 | loff_t dotdot_i_pos, new_i_pos; |
1da177e4 | 915 | int err, is_dir, update_dotdot, corrupt = 0; |
8f593427 | 916 | struct super_block *sb = old_dir->i_sb; |
1da177e4 LT |
917 | |
918 | old_sinfo.bh = sinfo.bh = dotdot_bh = NULL; | |
919 | old_inode = old_dentry->d_inode; | |
920 | new_inode = new_dentry->d_inode; | |
8f593427 | 921 | lock_super(sb); |
1da177e4 LT |
922 | err = vfat_find(old_dir, &old_dentry->d_name, &old_sinfo); |
923 | if (err) | |
924 | goto out; | |
925 | ||
926 | is_dir = S_ISDIR(old_inode->i_mode); | |
927 | update_dotdot = (is_dir && old_dir != new_dir); | |
928 | if (update_dotdot) { | |
929 | if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de, | |
930 | &dotdot_i_pos) < 0) { | |
931 | err = -EIO; | |
932 | goto out; | |
933 | } | |
934 | } | |
935 | ||
936 | ts = CURRENT_TIME_SEC; | |
937 | if (new_inode) { | |
1da177e4 LT |
938 | if (is_dir) { |
939 | err = fat_dir_empty(new_inode); | |
940 | if (err) | |
941 | goto out; | |
942 | } | |
9131dd42 | 943 | new_i_pos = MSDOS_I(new_inode)->i_pos; |
1da177e4 LT |
944 | fat_detach(new_inode); |
945 | } else { | |
946 | err = vfat_add_entry(new_dir, &new_dentry->d_name, is_dir, 0, | |
947 | &ts, &sinfo); | |
948 | if (err) | |
949 | goto out; | |
9131dd42 | 950 | new_i_pos = sinfo.i_pos; |
1da177e4 LT |
951 | } |
952 | new_dir->i_version++; | |
953 | ||
954 | fat_detach(old_inode); | |
9131dd42 | 955 | fat_attach(old_inode, new_i_pos); |
1da177e4 LT |
956 | if (IS_DIRSYNC(new_dir)) { |
957 | err = fat_sync_inode(old_inode); | |
958 | if (err) | |
959 | goto error_inode; | |
960 | } else | |
961 | mark_inode_dirty(old_inode); | |
962 | ||
963 | if (update_dotdot) { | |
964 | int start = MSDOS_I(new_dir)->i_logstart; | |
965 | dotdot_de->start = cpu_to_le16(start); | |
966 | dotdot_de->starthi = cpu_to_le16(start >> 16); | |
b522412a | 967 | mark_buffer_dirty_inode(dotdot_bh, old_inode); |
1da177e4 LT |
968 | if (IS_DIRSYNC(new_dir)) { |
969 | err = sync_dirty_buffer(dotdot_bh); | |
970 | if (err) | |
971 | goto error_dotdot; | |
972 | } | |
9a53c3a7 | 973 | drop_nlink(old_dir); |
1da177e4 | 974 | if (!new_inode) |
d8c76e6f | 975 | inc_nlink(new_dir); |
1da177e4 LT |
976 | } |
977 | ||
978 | err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */ | |
979 | old_sinfo.bh = NULL; | |
980 | if (err) | |
981 | goto error_dotdot; | |
982 | old_dir->i_version++; | |
983 | old_dir->i_ctime = old_dir->i_mtime = ts; | |
984 | if (IS_DIRSYNC(old_dir)) | |
985 | (void)fat_sync_inode(old_dir); | |
986 | else | |
987 | mark_inode_dirty(old_dir); | |
988 | ||
989 | if (new_inode) { | |
9a53c3a7 | 990 | drop_nlink(new_inode); |
1da177e4 | 991 | if (is_dir) |
9a53c3a7 | 992 | drop_nlink(new_inode); |
1da177e4 LT |
993 | new_inode->i_ctime = ts; |
994 | } | |
995 | out: | |
996 | brelse(sinfo.bh); | |
997 | brelse(dotdot_bh); | |
998 | brelse(old_sinfo.bh); | |
8f593427 | 999 | unlock_super(sb); |
1da177e4 LT |
1000 | |
1001 | return err; | |
1002 | ||
1003 | error_dotdot: | |
1004 | /* data cluster is shared, serious corruption */ | |
1005 | corrupt = 1; | |
1006 | ||
1007 | if (update_dotdot) { | |
1008 | int start = MSDOS_I(old_dir)->i_logstart; | |
1009 | dotdot_de->start = cpu_to_le16(start); | |
1010 | dotdot_de->starthi = cpu_to_le16(start >> 16); | |
b522412a | 1011 | mark_buffer_dirty_inode(dotdot_bh, old_inode); |
1da177e4 LT |
1012 | corrupt |= sync_dirty_buffer(dotdot_bh); |
1013 | } | |
1014 | error_inode: | |
1015 | fat_detach(old_inode); | |
1016 | fat_attach(old_inode, old_sinfo.i_pos); | |
1017 | if (new_inode) { | |
9131dd42 | 1018 | fat_attach(new_inode, new_i_pos); |
1da177e4 LT |
1019 | if (corrupt) |
1020 | corrupt |= fat_sync_inode(new_inode); | |
1021 | } else { | |
1022 | /* | |
1023 | * If new entry was not sharing the data cluster, it | |
1024 | * shouldn't be serious corruption. | |
1025 | */ | |
1026 | int err2 = fat_remove_entries(new_dir, &sinfo); | |
1027 | if (corrupt) | |
1028 | corrupt |= err2; | |
1029 | sinfo.bh = NULL; | |
1030 | } | |
1031 | if (corrupt < 0) { | |
85c78591 | 1032 | fat_fs_error(new_dir->i_sb, |
1da177e4 | 1033 | "%s: Filesystem corrupted (i_pos %lld)", |
8e24eea7 | 1034 | __func__, sinfo.i_pos); |
1da177e4 LT |
1035 | } |
1036 | goto out; | |
1037 | } | |
1038 | ||
c5ef1c42 | 1039 | static const struct inode_operations vfat_dir_inode_operations = { |
1da177e4 LT |
1040 | .create = vfat_create, |
1041 | .lookup = vfat_lookup, | |
1042 | .unlink = vfat_unlink, | |
1043 | .mkdir = vfat_mkdir, | |
1044 | .rmdir = vfat_rmdir, | |
1045 | .rename = vfat_rename, | |
1278fdd3 | 1046 | .setattr = fat_setattr, |
da63fc7c | 1047 | .getattr = fat_getattr, |
1da177e4 LT |
1048 | }; |
1049 | ||
1050 | static int vfat_fill_super(struct super_block *sb, void *data, int silent) | |
1051 | { | |
1052 | int res; | |
1053 | ||
1054 | res = fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, 1); | |
1055 | if (res) | |
1056 | return res; | |
1057 | ||
1058 | if (MSDOS_SB(sb)->options.name_check != 's') | |
1b524672 | 1059 | sb->s_root->d_op = &vfat_ci_dentry_ops; |
1da177e4 | 1060 | else |
1b524672 | 1061 | sb->s_root->d_op = &vfat_dentry_ops; |
1da177e4 LT |
1062 | |
1063 | return 0; | |
1064 | } | |
1065 | ||
454e2398 DH |
1066 | static int vfat_get_sb(struct file_system_type *fs_type, |
1067 | int flags, const char *dev_name, | |
1068 | void *data, struct vfsmount *mnt) | |
1da177e4 | 1069 | { |
454e2398 DH |
1070 | return get_sb_bdev(fs_type, flags, dev_name, data, vfat_fill_super, |
1071 | mnt); | |
1da177e4 LT |
1072 | } |
1073 | ||
1074 | static struct file_system_type vfat_fs_type = { | |
1075 | .owner = THIS_MODULE, | |
1076 | .name = "vfat", | |
1077 | .get_sb = vfat_get_sb, | |
1078 | .kill_sb = kill_block_super, | |
1079 | .fs_flags = FS_REQUIRES_DEV, | |
1080 | }; | |
1081 | ||
1082 | static int __init init_vfat_fs(void) | |
1083 | { | |
1084 | return register_filesystem(&vfat_fs_type); | |
1085 | } | |
1086 | ||
1087 | static void __exit exit_vfat_fs(void) | |
1088 | { | |
1089 | unregister_filesystem(&vfat_fs_type); | |
1090 | } | |
1091 | ||
1092 | MODULE_LICENSE("GPL"); | |
1093 | MODULE_DESCRIPTION("VFAT filesystem support"); | |
1094 | MODULE_AUTHOR("Gordon Chaffee"); | |
1095 | ||
1096 | module_init(init_vfat_fs) | |
1097 | module_exit(exit_vfat_fs) |