blob: adae3fb7451aa52670d07fdf34381defe133e73a [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/jiffies.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/ctype.h>
21#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/buffer_head.h>
23#include <linux/namei.h>
OGAWA Hirofumi9e975da2008-11-06 12:53:46 -080024#include "fat.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
OGAWA Hirofumi1b524672008-11-06 12:53:51 -080026/*
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 */
34static int vfat_revalidate_shortname(struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -070035{
36 int ret = 1;
OGAWA Hirofumi1b524672008-11-06 12:53:51 -080037 spin_lock(&dentry->d_lock);
38 if (dentry->d_time != dentry->d_parent->d_inode->i_version)
Linus Torvalds1da177e2005-04-16 15:20:36 -070039 ret = 0;
OGAWA Hirofumi1b524672008-11-06 12:53:51 -080040 spin_unlock(&dentry->d_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 return ret;
42}
43
OGAWA Hirofumi1b524672008-11-06 12:53:51 -080044static int vfat_revalidate(struct dentry *dentry, struct nameidata *nd)
45{
Al Viro9177ada2011-03-10 03:45:49 -050046 if (nd && nd->flags & LOOKUP_RCU)
Nick Piggin34286d62011-01-07 17:49:57 +110047 return -ECHILD;
48
OGAWA Hirofumi1b524672008-11-06 12:53:51 -080049 /* This is not negative dentry. Always valid. */
50 if (dentry->d_inode)
51 return 1;
52 return vfat_revalidate_shortname(dentry);
53}
54
55static int vfat_revalidate_ci(struct dentry *dentry, struct nameidata *nd)
56{
Al Viro9177ada2011-03-10 03:45:49 -050057 if (nd && nd->flags & LOOKUP_RCU)
Nick Piggin34286d62011-01-07 17:49:57 +110058 return -ECHILD;
59
OGAWA Hirofumi1b524672008-11-06 12:53:51 -080060 /*
61 * This is not negative dentry. Always valid.
62 *
63 * Note, rename() to existing directory entry will have ->d_inode,
64 * and will use existing name which isn't specified name by user.
65 *
66 * We may be able to drop this positive dentry here. But dropping
67 * positive dentry isn't good idea. So it's unsupported like
68 * rename("filename", "FILENAME") for now.
69 */
70 if (dentry->d_inode)
71 return 1;
72
73 /*
74 * This may be nfsd (or something), anyway, we can't see the
75 * intent of this. So, since this can be for creation, drop it.
76 */
77 if (!nd)
78 return 0;
79
80 /*
81 * Drop the negative dentry, in order to make sure to use the
82 * case sensitive name which is specified by user if this is
83 * for creation.
84 */
85 if (!(nd->flags & (LOOKUP_CONTINUE | LOOKUP_PARENT))) {
OGAWA Hirofumiebeb0402008-11-12 07:48:00 +090086 if (nd->flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
OGAWA Hirofumi1b524672008-11-06 12:53:51 -080087 return 0;
88 }
89
90 return vfat_revalidate_shortname(dentry);
91}
92
Linus Torvalds1da177e2005-04-16 15:20:36 -070093/* returns the length of a struct qstr, ignoring trailing dots */
Nick Piggin621e1552011-01-07 17:49:27 +110094static unsigned int __vfat_striptail_len(unsigned int len, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -070095{
Nick Piggin621e1552011-01-07 17:49:27 +110096 while (len && name[len - 1] == '.')
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 len--;
98 return len;
99}
100
Nick Piggin621e1552011-01-07 17:49:27 +1100101static unsigned int vfat_striptail_len(const struct qstr *qstr)
102{
103 return __vfat_striptail_len(qstr->len, qstr->name);
104}
105
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106/*
107 * Compute the hash for the vfat name corresponding to the dentry.
108 * Note: if the name is invalid, we leave the hash code unchanged so
109 * that the existing dentry can be used. The vfat fs routines will
110 * return ENOENT or EINVAL as appropriate.
111 */
Nick Pigginb1e6a012011-01-07 17:49:28 +1100112static int vfat_hash(const struct dentry *dentry, const struct inode *inode,
113 struct qstr *qstr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114{
115 qstr->hash = full_name_hash(qstr->name, vfat_striptail_len(qstr));
116 return 0;
117}
118
119/*
120 * Compute the hash for the vfat name corresponding to the dentry.
121 * Note: if the name is invalid, we leave the hash code unchanged so
122 * that the existing dentry can be used. The vfat fs routines will
123 * return ENOENT or EINVAL as appropriate.
124 */
Nick Pigginb1e6a012011-01-07 17:49:28 +1100125static int vfat_hashi(const struct dentry *dentry, const struct inode *inode,
126 struct qstr *qstr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127{
Nick Pigginb1e6a012011-01-07 17:49:28 +1100128 struct nls_table *t = MSDOS_SB(dentry->d_sb)->nls_io;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 const unsigned char *name;
130 unsigned int len;
131 unsigned long hash;
132
133 name = qstr->name;
134 len = vfat_striptail_len(qstr);
135
136 hash = init_name_hash();
137 while (len--)
138 hash = partial_name_hash(nls_tolower(t, *name++), hash);
139 qstr->hash = end_name_hash(hash);
140
141 return 0;
142}
143
144/*
145 * Case insensitive compare of two vfat names.
146 */
Nick Piggin621e1552011-01-07 17:49:27 +1100147static int vfat_cmpi(const struct dentry *parent, const struct inode *pinode,
148 const struct dentry *dentry, const struct inode *inode,
149 unsigned int len, const char *str, const struct qstr *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150{
Nick Piggin621e1552011-01-07 17:49:27 +1100151 struct nls_table *t = MSDOS_SB(parent->d_sb)->nls_io;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 unsigned int alen, blen;
153
154 /* A filename cannot end in '.' or we treat it like it has none */
Nick Piggin621e1552011-01-07 17:49:27 +1100155 alen = vfat_striptail_len(name);
156 blen = __vfat_striptail_len(len, str);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 if (alen == blen) {
Nick Piggin621e1552011-01-07 17:49:27 +1100158 if (nls_strnicmp(t, name->name, str, alen) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 return 0;
160 }
161 return 1;
162}
163
164/*
165 * Case sensitive compare of two vfat names.
166 */
Nick Piggin621e1552011-01-07 17:49:27 +1100167static int vfat_cmp(const struct dentry *parent, const struct inode *pinode,
168 const struct dentry *dentry, const struct inode *inode,
169 unsigned int len, const char *str, const struct qstr *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170{
171 unsigned int alen, blen;
172
173 /* A filename cannot end in '.' or we treat it like it has none */
Nick Piggin621e1552011-01-07 17:49:27 +1100174 alen = vfat_striptail_len(name);
175 blen = __vfat_striptail_len(len, str);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 if (alen == blen) {
Nick Piggin621e1552011-01-07 17:49:27 +1100177 if (strncmp(name->name, str, alen) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 return 0;
179 }
180 return 1;
181}
182
Al Viroce6cdc42009-02-20 05:59:46 +0000183static const struct dentry_operations vfat_ci_dentry_ops = {
OGAWA Hirofumi1b524672008-11-06 12:53:51 -0800184 .d_revalidate = vfat_revalidate_ci,
185 .d_hash = vfat_hashi,
186 .d_compare = vfat_cmpi,
187};
188
Al Viroce6cdc42009-02-20 05:59:46 +0000189static const struct dentry_operations vfat_dentry_ops = {
OGAWA Hirofumi1b524672008-11-06 12:53:51 -0800190 .d_revalidate = vfat_revalidate,
191 .d_hash = vfat_hash,
192 .d_compare = vfat_cmp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193};
194
195/* Characters that are undesirable in an MS-DOS file name */
196
197static inline wchar_t vfat_bad_char(wchar_t w)
198{
199 return (w < 0x0020)
200 || (w == '*') || (w == '?') || (w == '<') || (w == '>')
201 || (w == '|') || (w == '"') || (w == ':') || (w == '/')
202 || (w == '\\');
203}
204
205static inline wchar_t vfat_replace_char(wchar_t w)
206{
207 return (w == '[') || (w == ']') || (w == ';') || (w == ',')
208 || (w == '+') || (w == '=');
209}
210
211static wchar_t vfat_skip_char(wchar_t w)
212{
213 return (w == '.') || (w == ' ');
214}
215
216static inline int vfat_is_used_badchars(const wchar_t *s, int len)
217{
218 int i;
219
220 for (i = 0; i < len; i++)
221 if (vfat_bad_char(s[i]))
222 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223
Keith Mokf22032b2008-04-28 02:16:29 -0700224 if (s[i - 1] == ' ') /* last character cannot be space */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 return -EINVAL;
Keith Mokf22032b2008-04-28 02:16:29 -0700226
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 return 0;
228}
229
230static int vfat_find_form(struct inode *dir, unsigned char *name)
231{
232 struct fat_slot_info sinfo;
233 int err = fat_scan(dir, name, &sinfo);
234 if (err)
235 return -ENOENT;
236 brelse(sinfo.bh);
237 return 0;
238}
239
240/*
241 * 1) Valid characters for the 8.3 format alias are any combination of
242 * letters, uppercase alphabets, digits, any of the
243 * following special characters:
244 * $ % ' ` - @ { } ~ ! # ( ) & _ ^
245 * In this case Longfilename is not stored in disk.
246 *
247 * WinNT's Extension:
248 * File name and extension name is contain uppercase/lowercase
249 * only. And it is expressed by CASE_LOWER_BASE and CASE_LOWER_EXT.
250 *
251 * 2) File name is 8.3 format, but it contain the uppercase and
252 * lowercase char, muliti bytes char, etc. In this case numtail is not
253 * added, but Longfilename is stored.
254 *
255 * 3) When the one except for the above, or the following special
256 * character are contained:
257 * . [ ] ; , + =
258 * numtail is added, and Longfilename must be stored in disk .
259 */
260struct shortname_info {
261 unsigned char lower:1,
262 upper:1,
263 valid:1;
264};
265#define INIT_SHORTNAME_INFO(x) do { \
266 (x)->lower = 1; \
267 (x)->upper = 1; \
268 (x)->valid = 1; \
269} while (0)
270
271static inline int to_shortname_char(struct nls_table *nls,
272 unsigned char *buf, int buf_size,
273 wchar_t *src, struct shortname_info *info)
274{
275 int len;
276
277 if (vfat_skip_char(*src)) {
278 info->valid = 0;
279 return 0;
280 }
281 if (vfat_replace_char(*src)) {
282 info->valid = 0;
283 buf[0] = '_';
284 return 1;
285 }
286
287 len = nls->uni2char(*src, buf, buf_size);
288 if (len <= 0) {
289 info->valid = 0;
290 buf[0] = '_';
291 len = 1;
292 } else if (len == 1) {
293 unsigned char prev = buf[0];
294
295 if (buf[0] >= 0x7F) {
296 info->lower = 0;
297 info->upper = 0;
298 }
299
300 buf[0] = nls_toupper(nls, buf[0]);
301 if (isalpha(buf[0])) {
302 if (buf[0] == prev)
303 info->lower = 0;
304 else
305 info->upper = 0;
306 }
307 } else {
308 info->lower = 0;
309 info->upper = 0;
310 }
311
312 return len;
313}
314
315/*
316 * Given a valid longname, create a unique shortname. Make sure the
317 * shortname does not exist
318 * Returns negative number on error, 0 for a normal
319 * return, and 1 for valid shortname
320 */
321static int vfat_create_shortname(struct inode *dir, struct nls_table *nls,
322 wchar_t *uname, int ulen,
323 unsigned char *name_res, unsigned char *lcase)
324{
325 struct fat_mount_options *opts = &MSDOS_SB(dir->i_sb)->options;
326 wchar_t *ip, *ext_start, *end, *name_start;
Nikolaus Schulz30d18722010-04-01 02:21:10 +0900327 unsigned char base[9], ext[4], buf[5], *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 unsigned char charbuf[NLS_MAX_CHARSET_SIZE];
329 int chl, chi;
330 int sz = 0, extlen, baselen, i, numtail_baselen, numtail2_baselen;
331 int is_shortname;
332 struct shortname_info base_info, ext_info;
333
334 is_shortname = 1;
335 INIT_SHORTNAME_INFO(&base_info);
336 INIT_SHORTNAME_INFO(&ext_info);
337
338 /* Now, we need to create a shortname from the long name */
339 ext_start = end = &uname[ulen];
340 while (--ext_start >= uname) {
341 if (*ext_start == 0x002E) { /* is `.' */
342 if (ext_start == end - 1) {
343 sz = ulen;
344 ext_start = NULL;
345 }
346 break;
347 }
348 }
349
350 if (ext_start == uname - 1) {
351 sz = ulen;
352 ext_start = NULL;
353 } else if (ext_start) {
354 /*
355 * Names which start with a dot could be just
356 * an extension eg. "...test". In this case Win95
357 * uses the extension as the name and sets no extension.
358 */
359 name_start = &uname[0];
360 while (name_start < ext_start) {
361 if (!vfat_skip_char(*name_start))
362 break;
363 name_start++;
364 }
365 if (name_start != ext_start) {
366 sz = ext_start - uname;
367 ext_start++;
368 } else {
369 sz = ulen;
370 ext_start = NULL;
371 }
372 }
373
374 numtail_baselen = 6;
375 numtail2_baselen = 2;
376 for (baselen = i = 0, p = base, ip = uname; i < sz; i++, ip++) {
377 chl = to_shortname_char(nls, charbuf, sizeof(charbuf),
378 ip, &base_info);
379 if (chl == 0)
380 continue;
381
382 if (baselen < 2 && (baselen + chl) > 2)
383 numtail2_baselen = baselen;
384 if (baselen < 6 && (baselen + chl) > 6)
385 numtail_baselen = baselen;
386 for (chi = 0; chi < chl; chi++) {
387 *p++ = charbuf[chi];
388 baselen++;
389 if (baselen >= 8)
390 break;
391 }
392 if (baselen >= 8) {
393 if ((chi < chl - 1) || (ip + 1) - uname < sz)
394 is_shortname = 0;
395 break;
396 }
397 }
398 if (baselen == 0) {
399 return -EINVAL;
400 }
401
402 extlen = 0;
403 if (ext_start) {
404 for (p = ext, ip = ext_start; extlen < 3 && ip < end; ip++) {
405 chl = to_shortname_char(nls, charbuf, sizeof(charbuf),
406 ip, &ext_info);
407 if (chl == 0)
408 continue;
409
410 if ((extlen + chl) > 3) {
411 is_shortname = 0;
412 break;
413 }
414 for (chi = 0; chi < chl; chi++) {
415 *p++ = charbuf[chi];
416 extlen++;
417 }
418 if (extlen >= 3) {
419 if (ip + 1 != end)
420 is_shortname = 0;
421 break;
422 }
423 }
424 }
425 ext[extlen] = '\0';
426 base[baselen] = '\0';
427
428 /* Yes, it can happen. ".\xe5" would do it. */
429 if (base[0] == DELETED_FLAG)
430 base[0] = 0x05;
431
432 /* OK, at this point we know that base is not longer than 8 symbols,
433 * ext is not longer than 3, base is nonempty, both don't contain
434 * any bad symbols (lowercase transformed to uppercase).
435 */
436
437 memset(name_res, ' ', MSDOS_NAME);
438 memcpy(name_res, base, baselen);
439 memcpy(name_res + 8, ext, extlen);
440 *lcase = 0;
441 if (is_shortname && base_info.valid && ext_info.valid) {
442 if (vfat_find_form(dir, name_res) == 0)
443 return -EEXIST;
444
445 if (opts->shortname & VFAT_SFN_CREATE_WIN95) {
446 return (base_info.upper && ext_info.upper);
447 } else if (opts->shortname & VFAT_SFN_CREATE_WINNT) {
448 if ((base_info.upper || base_info.lower) &&
449 (ext_info.upper || ext_info.lower)) {
450 if (!base_info.upper && base_info.lower)
451 *lcase |= CASE_LOWER_BASE;
452 if (!ext_info.upper && ext_info.lower)
453 *lcase |= CASE_LOWER_EXT;
454 return 1;
455 }
456 return 0;
457 } else {
458 BUG();
459 }
460 }
461
462 if (opts->numtail == 0)
463 if (vfat_find_form(dir, name_res) < 0)
464 return 0;
465
466 /*
467 * Try to find a unique extension. This used to
468 * iterate through all possibilities sequentially,
469 * but that gave extremely bad performance. Windows
470 * only tries a few cases before using random
471 * values for part of the base.
472 */
473
474 if (baselen > 6) {
475 baselen = numtail_baselen;
476 name_res[7] = ' ';
477 }
478 name_res[baselen] = '~';
479 for (i = 1; i < 10; i++) {
480 name_res[baselen + 1] = i + '0';
481 if (vfat_find_form(dir, name_res) < 0)
482 return 0;
483 }
484
Nikolaus Schulz30d18722010-04-01 02:21:10 +0900485 i = jiffies;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 sz = (jiffies >> 16) & 0x7;
487 if (baselen > 2) {
488 baselen = numtail2_baselen;
489 name_res[7] = ' ';
490 }
491 name_res[baselen + 4] = '~';
492 name_res[baselen + 5] = '1' + sz;
493 while (1) {
Nikolaus Schulz30d18722010-04-01 02:21:10 +0900494 snprintf(buf, sizeof(buf), "%04X", i & 0xffff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 memcpy(&name_res[baselen], buf, 4);
496 if (vfat_find_form(dir, name_res) < 0)
497 break;
498 i -= 11;
499 }
500 return 0;
501}
502
503/* Translate a string, including coded sequences into Unicode */
504static int
505xlate_to_uni(const unsigned char *name, int len, unsigned char *outname,
506 int *longlen, int *outlen, int escape, int utf8,
507 struct nls_table *nls)
508{
509 const unsigned char *ip;
510 unsigned char nc;
511 unsigned char *op;
512 unsigned int ec;
513 int i, k, fill;
514 int charlen;
515
516 if (utf8) {
OGAWA Hirofumi67638e42009-08-01 21:30:31 +0900517 *outlen = utf8s_to_utf16s(name, len, (wchar_t *)outname);
518 if (*outlen < 0)
519 return *outlen;
Kevin Dankwardteeb5b4a2010-02-10 23:43:40 +0900520 else if (*outlen > FAT_LFN_LEN)
Keith Mokf22032b2008-04-28 02:16:29 -0700521 return -ENAMETOOLONG;
522
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 op = &outname[*outlen * sizeof(wchar_t)];
524 } else {
525 if (nls) {
526 for (i = 0, ip = name, op = outname, *outlen = 0;
Kevin Dankwardteeb5b4a2010-02-10 23:43:40 +0900527 i < len && *outlen <= FAT_LFN_LEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 *outlen += 1)
529 {
530 if (escape && (*ip == ':')) {
531 if (i > len - 5)
532 return -EINVAL;
533 ec = 0;
534 for (k = 1; k < 5; k++) {
535 nc = ip[k];
536 ec <<= 4;
537 if (nc >= '0' && nc <= '9') {
538 ec |= nc - '0';
539 continue;
540 }
541 if (nc >= 'a' && nc <= 'f') {
542 ec |= nc - ('a' - 10);
543 continue;
544 }
545 if (nc >= 'A' && nc <= 'F') {
546 ec |= nc - ('A' - 10);
547 continue;
548 }
549 return -EINVAL;
550 }
551 *op++ = ec & 0xFF;
552 *op++ = ec >> 8;
553 ip += 5;
554 i += 5;
555 } else {
556 if ((charlen = nls->char2uni(ip, len - i, (wchar_t *)op)) < 0)
557 return -EINVAL;
558 ip += charlen;
559 i += charlen;
560 op += 2;
561 }
562 }
Keith Mokf22032b2008-04-28 02:16:29 -0700563 if (i < len)
564 return -ENAMETOOLONG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 } else {
566 for (i = 0, ip = name, op = outname, *outlen = 0;
Kevin Dankwardteeb5b4a2010-02-10 23:43:40 +0900567 i < len && *outlen <= FAT_LFN_LEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 i++, *outlen += 1)
569 {
570 *op++ = *ip++;
571 *op++ = 0;
572 }
Keith Mokf22032b2008-04-28 02:16:29 -0700573 if (i < len)
574 return -ENAMETOOLONG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 }
576 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577
578 *longlen = *outlen;
579 if (*outlen % 13) {
580 *op++ = 0;
581 *op++ = 0;
582 *outlen += 1;
583 if (*outlen % 13) {
584 fill = 13 - (*outlen % 13);
585 for (i = 0; i < fill; i++) {
586 *op++ = 0xff;
587 *op++ = 0xff;
588 }
589 *outlen += fill;
590 }
591 }
592
593 return 0;
594}
595
596static int vfat_build_slots(struct inode *dir, const unsigned char *name,
597 int len, int is_dir, int cluster,
598 struct timespec *ts,
599 struct msdos_dir_slot *slots, int *nr_slots)
600{
601 struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
602 struct fat_mount_options *opts = &sbi->options;
603 struct msdos_dir_slot *ps;
604 struct msdos_dir_entry *de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 unsigned char cksum, lcase;
606 unsigned char msdos_name[MSDOS_NAME];
607 wchar_t *uname;
608 __le16 time, date;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800609 u8 time_cs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 int err, ulen, usize, i;
611 loff_t offset;
612
613 *nr_slots = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614
OGAWA Hirofumic7a6c4e2008-04-28 02:16:29 -0700615 uname = __getname();
616 if (!uname)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 return -ENOMEM;
618
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 err = xlate_to_uni(name, len, (unsigned char *)uname, &ulen, &usize,
620 opts->unicode_xlate, opts->utf8, sbi->nls_io);
621 if (err)
622 goto out_free;
623
624 err = vfat_is_used_badchars(uname, ulen);
625 if (err)
626 goto out_free;
627
628 err = vfat_create_shortname(dir, sbi->nls_disk, uname, ulen,
629 msdos_name, &lcase);
630 if (err < 0)
631 goto out_free;
632 else if (err == 1) {
633 de = (struct msdos_dir_entry *)slots;
634 err = 0;
635 goto shortname;
636 }
637
638 /* build the entry of long file name */
OGAWA Hirofumi451cbaa2005-10-30 15:03:49 -0800639 cksum = fat_checksum(msdos_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640
641 *nr_slots = usize / 13;
642 for (ps = slots, i = *nr_slots; i > 0; i--, ps++) {
643 ps->id = i;
644 ps->attr = ATTR_EXT;
645 ps->reserved = 0;
646 ps->alias_checksum = cksum;
647 ps->start = 0;
648 offset = (i - 1) * 13;
649 fatwchar_to16(ps->name0_4, uname + offset, 5);
650 fatwchar_to16(ps->name5_10, uname + offset + 5, 6);
651 fatwchar_to16(ps->name11_12, uname + offset + 11, 2);
652 }
653 slots[0].id |= 0x40;
654 de = (struct msdos_dir_entry *)ps;
655
656shortname:
657 /* build the entry of 8.3 alias name */
658 (*nr_slots)++;
659 memcpy(de->name, msdos_name, MSDOS_NAME);
660 de->attr = is_dir ? ATTR_DIR : ATTR_ARCH;
661 de->lcase = lcase;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800662 fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 de->time = de->ctime = time;
664 de->date = de->cdate = de->adate = date;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800665 de->ctime_cs = time_cs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 de->start = cpu_to_le16(cluster);
667 de->starthi = cpu_to_le16(cluster >> 16);
668 de->size = 0;
669out_free:
OGAWA Hirofumic7a6c4e2008-04-28 02:16:29 -0700670 __putname(uname);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 return err;
672}
673
674static int vfat_add_entry(struct inode *dir, struct qstr *qname, int is_dir,
675 int cluster, struct timespec *ts,
676 struct fat_slot_info *sinfo)
677{
678 struct msdos_dir_slot *slots;
679 unsigned int len;
680 int err, nr_slots;
681
682 len = vfat_striptail_len(qname);
683 if (len == 0)
684 return -ENOENT;
685
Linus Torvalds8f593422008-05-19 19:53:01 -0700686 slots = kmalloc(sizeof(*slots) * MSDOS_SLOTS, GFP_NOFS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 if (slots == NULL)
688 return -ENOMEM;
689
690 err = vfat_build_slots(dir, qname->name, len, is_dir, cluster, ts,
691 slots, &nr_slots);
692 if (err)
693 goto cleanup;
694
695 err = fat_add_entries(dir, slots, nr_slots, sinfo);
696 if (err)
697 goto cleanup;
698
699 /* update timestamp */
700 dir->i_ctime = dir->i_mtime = dir->i_atime = *ts;
701 if (IS_DIRSYNC(dir))
702 (void)fat_sync_inode(dir);
703 else
704 mark_inode_dirty(dir);
705cleanup:
706 kfree(slots);
707 return err;
708}
709
710static int vfat_find(struct inode *dir, struct qstr *qname,
711 struct fat_slot_info *sinfo)
712{
713 unsigned int len = vfat_striptail_len(qname);
714 if (len == 0)
715 return -ENOENT;
716 return fat_search_long(dir, qname->name, len, sinfo);
717}
718
OGAWA Hirofumi8045e292010-01-12 03:32:24 +0900719/*
720 * (nfsd's) anonymous disconnected dentry?
721 * NOTE: !IS_ROOT() is not anonymous (I.e. d_splice_alias() did the job).
722 */
723static int vfat_d_anon_disconn(struct dentry *dentry)
724{
725 return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
726}
727
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry,
729 struct nameidata *nd)
730{
731 struct super_block *sb = dir->i_sb;
732 struct fat_slot_info sinfo;
OGAWA Hirofumi068f5ae2008-11-06 12:53:51 -0800733 struct inode *inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 struct dentry *alias;
OGAWA Hirofumi1b524672008-11-06 12:53:51 -0800735 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736
Linus Torvalds8f593422008-05-19 19:53:01 -0700737 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738
739 err = vfat_find(dir, &dentry->d_name, &sinfo);
740 if (err) {
OGAWA Hirofumi068f5ae2008-11-06 12:53:51 -0800741 if (err == -ENOENT) {
OGAWA Hirofumi068f5ae2008-11-06 12:53:51 -0800742 inode = NULL;
743 goto out;
744 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 goto error;
746 }
OGAWA Hirofumi1b524672008-11-06 12:53:51 -0800747
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
749 brelse(sinfo.bh);
750 if (IS_ERR(inode)) {
OGAWA Hirofumi068f5ae2008-11-06 12:53:51 -0800751 err = PTR_ERR(inode);
752 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 }
OGAWA Hirofumi1b524672008-11-06 12:53:51 -0800754
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 alias = d_find_alias(inode);
OGAWA Hirofumi8045e292010-01-12 03:32:24 +0900756 if (alias && !vfat_d_anon_disconn(alias)) {
OGAWA Hirofumi1b524672008-11-06 12:53:51 -0800757 /*
OGAWA Hirofumi8045e292010-01-12 03:32:24 +0900758 * This inode has non anonymous-DCACHE_DISCONNECTED
759 * dentry. This means, the user did ->lookup() by an
760 * another name (longname vs 8.3 alias of it) in past.
OGAWA Hirofumi1b524672008-11-06 12:53:51 -0800761 *
762 * Switch to new one for reason of locality if possible.
763 */
OGAWA Hirofumi1c13a242008-11-06 12:53:52 -0800764 BUG_ON(d_unhashed(alias));
765 if (!S_ISDIR(inode->i_mode))
766 d_move(alias, dentry);
767 iput(inode);
768 unlock_super(sb);
769 return alias;
OGAWA Hirofumi8045e292010-01-12 03:32:24 +0900770 } else
771 dput(alias);
772
OGAWA Hirofumi068f5ae2008-11-06 12:53:51 -0800773out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700774 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 dentry->d_time = dentry->d_parent->d_inode->i_version;
776 dentry = d_splice_alias(inode, dentry);
Al Viro3d239852010-12-18 10:44:00 -0500777 if (dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778 dentry->d_time = dentry->d_parent->d_inode->i_version;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779 return dentry;
OGAWA Hirofumi068f5ae2008-11-06 12:53:51 -0800780
781error:
782 unlock_super(sb);
783 return ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784}
785
786static int vfat_create(struct inode *dir, struct dentry *dentry, int mode,
787 struct nameidata *nd)
788{
789 struct super_block *sb = dir->i_sb;
790 struct inode *inode;
791 struct fat_slot_info sinfo;
792 struct timespec ts;
793 int err;
794
Linus Torvalds8f593422008-05-19 19:53:01 -0700795 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796
797 ts = CURRENT_TIME_SEC;
798 err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &ts, &sinfo);
799 if (err)
800 goto out;
801 dir->i_version++;
802
803 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
804 brelse(sinfo.bh);
805 if (IS_ERR(inode)) {
806 err = PTR_ERR(inode);
807 goto out;
808 }
809 inode->i_version++;
810 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
811 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
812
813 dentry->d_time = dentry->d_parent->d_inode->i_version;
814 d_instantiate(dentry, inode);
815out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700816 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 return err;
818}
819
820static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
821{
822 struct inode *inode = dentry->d_inode;
Linus Torvalds8f593422008-05-19 19:53:01 -0700823 struct super_block *sb = dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824 struct fat_slot_info sinfo;
825 int err;
826
Linus Torvalds8f593422008-05-19 19:53:01 -0700827 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828
829 err = fat_dir_empty(inode);
830 if (err)
831 goto out;
832 err = vfat_find(dir, &dentry->d_name, &sinfo);
833 if (err)
834 goto out;
835
836 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
837 if (err)
838 goto out;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700839 drop_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840
Dave Hansence71ec32006-09-30 23:29:06 -0700841 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
843 fat_detach(inode);
844out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700845 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846
847 return err;
848}
849
850static int vfat_unlink(struct inode *dir, struct dentry *dentry)
851{
852 struct inode *inode = dentry->d_inode;
Linus Torvalds8f593422008-05-19 19:53:01 -0700853 struct super_block *sb = dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854 struct fat_slot_info sinfo;
855 int err;
856
Linus Torvalds8f593422008-05-19 19:53:01 -0700857 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858
859 err = vfat_find(dir, &dentry->d_name, &sinfo);
860 if (err)
861 goto out;
862
863 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
864 if (err)
865 goto out;
Dave Hansence71ec32006-09-30 23:29:06 -0700866 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
868 fat_detach(inode);
869out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700870 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871
872 return err;
873}
874
875static int vfat_mkdir(struct inode *dir, struct dentry *dentry, int mode)
876{
877 struct super_block *sb = dir->i_sb;
878 struct inode *inode;
879 struct fat_slot_info sinfo;
880 struct timespec ts;
881 int err, cluster;
882
Linus Torvalds8f593422008-05-19 19:53:01 -0700883 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884
885 ts = CURRENT_TIME_SEC;
886 cluster = fat_alloc_new_dir(dir, &ts);
887 if (cluster < 0) {
888 err = cluster;
889 goto out;
890 }
891 err = vfat_add_entry(dir, &dentry->d_name, 1, cluster, &ts, &sinfo);
892 if (err)
893 goto out_free;
894 dir->i_version++;
Dave Hansend8c76e62006-09-30 23:29:04 -0700895 inc_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700896
897 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
898 brelse(sinfo.bh);
899 if (IS_ERR(inode)) {
900 err = PTR_ERR(inode);
901 /* the directory was completed, just return a error */
902 goto out;
903 }
904 inode->i_version++;
905 inode->i_nlink = 2;
906 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
907 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
908
909 dentry->d_time = dentry->d_parent->d_inode->i_version;
910 d_instantiate(dentry, inode);
911
Linus Torvalds8f593422008-05-19 19:53:01 -0700912 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913 return 0;
914
915out_free:
916 fat_free_clusters(dir, cluster);
917out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700918 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919 return err;
920}
921
922static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
923 struct inode *new_dir, struct dentry *new_dentry)
924{
925 struct buffer_head *dotdot_bh;
926 struct msdos_dir_entry *dotdot_de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927 struct inode *old_inode, *new_inode;
928 struct fat_slot_info old_sinfo, sinfo;
929 struct timespec ts;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800930 loff_t dotdot_i_pos, new_i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 int err, is_dir, update_dotdot, corrupt = 0;
Linus Torvalds8f593422008-05-19 19:53:01 -0700932 struct super_block *sb = old_dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933
934 old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
935 old_inode = old_dentry->d_inode;
936 new_inode = new_dentry->d_inode;
Linus Torvalds8f593422008-05-19 19:53:01 -0700937 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 err = vfat_find(old_dir, &old_dentry->d_name, &old_sinfo);
939 if (err)
940 goto out;
941
942 is_dir = S_ISDIR(old_inode->i_mode);
943 update_dotdot = (is_dir && old_dir != new_dir);
944 if (update_dotdot) {
945 if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de,
946 &dotdot_i_pos) < 0) {
947 err = -EIO;
948 goto out;
949 }
950 }
951
952 ts = CURRENT_TIME_SEC;
953 if (new_inode) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954 if (is_dir) {
955 err = fat_dir_empty(new_inode);
956 if (err)
957 goto out;
958 }
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800959 new_i_pos = MSDOS_I(new_inode)->i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960 fat_detach(new_inode);
961 } else {
962 err = vfat_add_entry(new_dir, &new_dentry->d_name, is_dir, 0,
963 &ts, &sinfo);
964 if (err)
965 goto out;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800966 new_i_pos = sinfo.i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 }
968 new_dir->i_version++;
969
970 fat_detach(old_inode);
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800971 fat_attach(old_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972 if (IS_DIRSYNC(new_dir)) {
973 err = fat_sync_inode(old_inode);
974 if (err)
975 goto error_inode;
976 } else
977 mark_inode_dirty(old_inode);
978
979 if (update_dotdot) {
980 int start = MSDOS_I(new_dir)->i_logstart;
981 dotdot_de->start = cpu_to_le16(start);
982 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -0400983 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984 if (IS_DIRSYNC(new_dir)) {
985 err = sync_dirty_buffer(dotdot_bh);
986 if (err)
987 goto error_dotdot;
988 }
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700989 drop_nlink(old_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990 if (!new_inode)
Dave Hansend8c76e62006-09-30 23:29:04 -0700991 inc_nlink(new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992 }
993
994 err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */
995 old_sinfo.bh = NULL;
996 if (err)
997 goto error_dotdot;
998 old_dir->i_version++;
999 old_dir->i_ctime = old_dir->i_mtime = ts;
1000 if (IS_DIRSYNC(old_dir))
1001 (void)fat_sync_inode(old_dir);
1002 else
1003 mark_inode_dirty(old_dir);
1004
1005 if (new_inode) {
Dave Hansen9a53c3a2006-09-30 23:29:03 -07001006 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007 if (is_dir)
Dave Hansen9a53c3a2006-09-30 23:29:03 -07001008 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009 new_inode->i_ctime = ts;
1010 }
1011out:
1012 brelse(sinfo.bh);
1013 brelse(dotdot_bh);
1014 brelse(old_sinfo.bh);
Linus Torvalds8f593422008-05-19 19:53:01 -07001015 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016
1017 return err;
1018
1019error_dotdot:
1020 /* data cluster is shared, serious corruption */
1021 corrupt = 1;
1022
1023 if (update_dotdot) {
1024 int start = MSDOS_I(old_dir)->i_logstart;
1025 dotdot_de->start = cpu_to_le16(start);
1026 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -04001027 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028 corrupt |= sync_dirty_buffer(dotdot_bh);
1029 }
1030error_inode:
1031 fat_detach(old_inode);
1032 fat_attach(old_inode, old_sinfo.i_pos);
1033 if (new_inode) {
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -08001034 fat_attach(new_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035 if (corrupt)
1036 corrupt |= fat_sync_inode(new_inode);
1037 } else {
1038 /*
1039 * If new entry was not sharing the data cluster, it
1040 * shouldn't be serious corruption.
1041 */
1042 int err2 = fat_remove_entries(new_dir, &sinfo);
1043 if (corrupt)
1044 corrupt |= err2;
1045 sinfo.bh = NULL;
1046 }
1047 if (corrupt < 0) {
Denis Karpov85c78592009-06-04 02:34:22 +09001048 fat_fs_error(new_dir->i_sb,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049 "%s: Filesystem corrupted (i_pos %lld)",
Harvey Harrison8e24eea2008-04-30 00:55:09 -07001050 __func__, sinfo.i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 }
1052 goto out;
1053}
1054
Arjan van de Venc5ef1c42007-02-12 00:55:40 -08001055static const struct inode_operations vfat_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056 .create = vfat_create,
1057 .lookup = vfat_lookup,
1058 .unlink = vfat_unlink,
1059 .mkdir = vfat_mkdir,
1060 .rmdir = vfat_rmdir,
1061 .rename = vfat_rename,
OGAWA Hirofumi1278fdd2008-04-28 02:16:25 -07001062 .setattr = fat_setattr,
OGAWA Hirofumida63fc72006-11-16 01:19:28 -08001063 .getattr = fat_getattr,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001064};
1065
Al Viro3d239852010-12-18 10:44:00 -05001066static void setup(struct super_block *sb)
1067{
1068 if (MSDOS_SB(sb)->options.name_check != 's')
1069 sb->s_d_op = &vfat_ci_dentry_ops;
1070 else
1071 sb->s_d_op = &vfat_dentry_ops;
1072}
1073
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074static int vfat_fill_super(struct super_block *sb, void *data, int silent)
1075{
Al Viro3d239852010-12-18 10:44:00 -05001076 return fat_fill_super(sb, data, silent, &vfat_dir_inode_operations,
1077 1, setup);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078}
1079
Al Viro152a0832010-07-25 00:46:55 +04001080static struct dentry *vfat_mount(struct file_system_type *fs_type,
David Howells454e2392006-06-23 02:02:57 -07001081 int flags, const char *dev_name,
Al Viro152a0832010-07-25 00:46:55 +04001082 void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083{
Al Viro152a0832010-07-25 00:46:55 +04001084 return mount_bdev(fs_type, flags, dev_name, data, vfat_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085}
1086
1087static struct file_system_type vfat_fs_type = {
1088 .owner = THIS_MODULE,
1089 .name = "vfat",
Al Viro152a0832010-07-25 00:46:55 +04001090 .mount = vfat_mount,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091 .kill_sb = kill_block_super,
1092 .fs_flags = FS_REQUIRES_DEV,
1093};
1094
1095static int __init init_vfat_fs(void)
1096{
1097 return register_filesystem(&vfat_fs_type);
1098}
1099
1100static void __exit exit_vfat_fs(void)
1101{
1102 unregister_filesystem(&vfat_fs_type);
1103}
1104
1105MODULE_LICENSE("GPL");
1106MODULE_DESCRIPTION("VFAT filesystem support");
1107MODULE_AUTHOR("Gordon Chaffee");
1108
1109module_init(init_vfat_fs)
1110module_exit(exit_vfat_fs)