blob: e844b9809d27de0aa1447dec920087b6978b8c7c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/msdos/namei.c
3 *
4 * Written 1992,1993 by Werner Almesberger
5 * Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu>
6 * Rewritten for constant inumbers 1999 by Al Viro
7 */
8
9#include <linux/module.h>
10#include <linux/time.h>
11#include <linux/buffer_head.h>
12#include <linux/msdos_fs.h>
13#include <linux/smp_lock.h>
14
Linus Torvalds1da177e2005-04-16 15:20:36 -070015/* Characters that are undesirable in an MS-DOS file name */
16static unsigned char bad_chars[] = "*?<>|\"";
Rene Scharfe7557bc62008-07-25 01:46:45 -070017static unsigned char bad_if_strict[] = "+=,; ";
Linus Torvalds1da177e2005-04-16 15:20:36 -070018
19/***** Formats an MS-DOS file name. Rejects invalid names. */
20static int msdos_format_name(const unsigned char *name, int len,
21 unsigned char *res, struct fat_mount_options *opts)
22 /*
23 * name is the proposed name, len is its length, res is
24 * the resulting name, opts->name_check is either (r)elaxed,
25 * (n)ormal or (s)trict, opts->dotsOK allows dots at the
26 * beginning of name (for hidden files)
27 */
28{
29 unsigned char *walk;
Linus Torvalds1da177e2005-04-16 15:20:36 -070030 unsigned char c;
31 int space;
32
33 if (name[0] == '.') { /* dotfile because . and .. already done */
34 if (opts->dotsOK) {
35 /* Get rid of dot - test for it elsewhere */
36 name++;
37 len--;
Rene Scharfe7557bc62008-07-25 01:46:45 -070038 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -070039 return -EINVAL;
40 }
41 /*
Rene Scharfe7557bc62008-07-25 01:46:45 -070042 * disallow names that _really_ start with a dot
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 */
Rene Scharfe7557bc62008-07-25 01:46:45 -070044 space = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 c = 0;
46 for (walk = res; len && walk - res < 8; walk++) {
47 c = *name++;
48 len--;
49 if (opts->name_check != 'r' && strchr(bad_chars, c))
50 return -EINVAL;
Rene Scharfe7557bc62008-07-25 01:46:45 -070051 if (opts->name_check == 's' && strchr(bad_if_strict, c))
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 return -EINVAL;
53 if (c >= 'A' && c <= 'Z' && opts->name_check == 's')
54 return -EINVAL;
55 if (c < ' ' || c == ':' || c == '\\')
56 return -EINVAL;
57 /*
58 * 0xE5 is legal as a first character, but we must substitute
59 * 0x05 because 0xE5 marks deleted files. Yes, DOS really
60 * does this.
61 * It seems that Microsoft hacked DOS to support non-US
62 * characters after the 0xE5 character was already in use to
63 * mark deleted files.
64 */
65 if ((res == walk) && (c == 0xE5))
66 c = 0x05;
67 if (c == '.')
68 break;
69 space = (c == ' ');
70 *walk = (!opts->nocase && c >= 'a' && c <= 'z') ? c - 32 : c;
71 }
72 if (space)
73 return -EINVAL;
74 if (opts->name_check == 's' && len && c != '.') {
75 c = *name++;
76 len--;
77 if (c != '.')
78 return -EINVAL;
79 }
80 while (c != '.' && len--)
81 c = *name++;
82 if (c == '.') {
83 while (walk - res < 8)
84 *walk++ = ' ';
85 while (len > 0 && walk - res < MSDOS_NAME) {
86 c = *name++;
87 len--;
88 if (opts->name_check != 'r' && strchr(bad_chars, c))
89 return -EINVAL;
90 if (opts->name_check == 's' &&
Rene Scharfe7557bc62008-07-25 01:46:45 -070091 strchr(bad_if_strict, c))
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 return -EINVAL;
93 if (c < ' ' || c == ':' || c == '\\')
94 return -EINVAL;
95 if (c == '.') {
96 if (opts->name_check == 's')
97 return -EINVAL;
98 break;
99 }
100 if (c >= 'A' && c <= 'Z' && opts->name_check == 's')
101 return -EINVAL;
102 space = c == ' ';
103 if (!opts->nocase && c >= 'a' && c <= 'z')
104 *walk++ = c - 32;
105 else
106 *walk++ = c;
107 }
108 if (space)
109 return -EINVAL;
110 if (opts->name_check == 's' && len)
111 return -EINVAL;
112 }
113 while (walk - res < MSDOS_NAME)
114 *walk++ = ' ';
OGAWA Hirofumi094e3202006-03-31 02:30:53 -0800115
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 return 0;
117}
118
119/***** Locates a directory entry. Uses unformatted name. */
120static int msdos_find(struct inode *dir, const unsigned char *name, int len,
121 struct fat_slot_info *sinfo)
122{
123 struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
124 unsigned char msdos_name[MSDOS_NAME];
125 int err;
126
127 err = msdos_format_name(name, len, msdos_name, &sbi->options);
128 if (err)
129 return -ENOENT;
130
131 err = fat_scan(dir, msdos_name, sinfo);
132 if (!err && sbi->options.dotsOK) {
133 if (name[0] == '.') {
134 if (!(sinfo->de->attr & ATTR_HIDDEN))
135 err = -ENOENT;
136 } else {
137 if (sinfo->de->attr & ATTR_HIDDEN)
138 err = -ENOENT;
139 }
140 if (err)
141 brelse(sinfo->bh);
142 }
143 return err;
144}
145
146/*
147 * Compute the hash for the msdos name corresponding to the dentry.
148 * Note: if the name is invalid, we leave the hash code unchanged so
149 * that the existing dentry can be used. The msdos fs routines will
150 * return ENOENT or EINVAL as appropriate.
151 */
152static int msdos_hash(struct dentry *dentry, struct qstr *qstr)
153{
154 struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;
155 unsigned char msdos_name[MSDOS_NAME];
156 int error;
157
158 error = msdos_format_name(qstr->name, qstr->len, msdos_name, options);
159 if (!error)
160 qstr->hash = full_name_hash(msdos_name, MSDOS_NAME);
161 return 0;
162}
163
164/*
165 * Compare two msdos names. If either of the names are invalid,
166 * we fall back to doing the standard name comparison.
167 */
168static int msdos_cmp(struct dentry *dentry, struct qstr *a, struct qstr *b)
169{
170 struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;
171 unsigned char a_msdos_name[MSDOS_NAME], b_msdos_name[MSDOS_NAME];
172 int error;
173
174 error = msdos_format_name(a->name, a->len, a_msdos_name, options);
175 if (error)
176 goto old_compare;
177 error = msdos_format_name(b->name, b->len, b_msdos_name, options);
178 if (error)
179 goto old_compare;
180 error = memcmp(a_msdos_name, b_msdos_name, MSDOS_NAME);
181out:
182 return error;
183
184old_compare:
185 error = 1;
186 if (a->len == b->len)
187 error = memcmp(a->name, b->name, a->len);
188 goto out;
189}
190
191static struct dentry_operations msdos_dentry_operations = {
192 .d_hash = msdos_hash,
193 .d_compare = msdos_cmp,
194};
195
196/*
197 * AV. Wrappers for FAT sb operations. Is it wise?
198 */
199
200/***** Get inode using directory and name */
201static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry,
202 struct nameidata *nd)
203{
204 struct super_block *sb = dir->i_sb;
205 struct fat_slot_info sinfo;
206 struct inode *inode = NULL;
207 int res;
208
209 dentry->d_op = &msdos_dentry_operations;
210
Linus Torvalds8f593422008-05-19 19:53:01 -0700211 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 res = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
213 if (res == -ENOENT)
214 goto add;
215 if (res < 0)
216 goto out;
217 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
218 brelse(sinfo.bh);
219 if (IS_ERR(inode)) {
220 res = PTR_ERR(inode);
221 goto out;
222 }
223add:
224 res = 0;
225 dentry = d_splice_alias(inode, dentry);
226 if (dentry)
227 dentry->d_op = &msdos_dentry_operations;
228out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700229 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 if (!res)
231 return dentry;
232 return ERR_PTR(res);
233}
234
235/***** Creates a directory entry (name is already formatted). */
236static int msdos_add_entry(struct inode *dir, const unsigned char *name,
237 int is_dir, int is_hid, int cluster,
238 struct timespec *ts, struct fat_slot_info *sinfo)
239{
Joe Petersonb271e062008-07-25 01:46:47 -0700240 struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 struct msdos_dir_entry de;
242 __le16 time, date;
243 int err;
244
245 memcpy(de.name, name, MSDOS_NAME);
246 de.attr = is_dir ? ATTR_DIR : ATTR_ARCH;
247 if (is_hid)
248 de.attr |= ATTR_HIDDEN;
249 de.lcase = 0;
Joe Petersonb271e062008-07-25 01:46:47 -0700250 fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 de.cdate = de.adate = 0;
252 de.ctime = 0;
253 de.ctime_cs = 0;
254 de.time = time;
255 de.date = date;
256 de.start = cpu_to_le16(cluster);
257 de.starthi = cpu_to_le16(cluster >> 16);
258 de.size = 0;
259
260 err = fat_add_entries(dir, &de, 1, sinfo);
261 if (err)
262 return err;
263
264 dir->i_ctime = dir->i_mtime = *ts;
265 if (IS_DIRSYNC(dir))
266 (void)fat_sync_inode(dir);
267 else
268 mark_inode_dirty(dir);
269
270 return 0;
271}
272
273/***** Create a file */
274static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
275 struct nameidata *nd)
276{
277 struct super_block *sb = dir->i_sb;
Chris Masonae78bf92006-09-29 02:00:03 -0700278 struct inode *inode = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 struct fat_slot_info sinfo;
280 struct timespec ts;
281 unsigned char msdos_name[MSDOS_NAME];
282 int err, is_hid;
283
Linus Torvalds8f593422008-05-19 19:53:01 -0700284 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285
286 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
287 msdos_name, &MSDOS_SB(sb)->options);
288 if (err)
289 goto out;
290 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
291 /* Have to do it due to foo vs. .foo conflicts */
292 if (!fat_scan(dir, msdos_name, &sinfo)) {
293 brelse(sinfo.bh);
294 err = -EINVAL;
295 goto out;
296 }
297
298 ts = CURRENT_TIME_SEC;
299 err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &ts, &sinfo);
300 if (err)
301 goto out;
302 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
303 brelse(sinfo.bh);
304 if (IS_ERR(inode)) {
305 err = PTR_ERR(inode);
306 goto out;
307 }
308 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
309 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
310
311 d_instantiate(dentry, inode);
312out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700313 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700314 if (!err)
315 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 return err;
317}
318
319/***** Remove a directory */
320static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
321{
Linus Torvalds8f593422008-05-19 19:53:01 -0700322 struct super_block *sb = dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 struct inode *inode = dentry->d_inode;
324 struct fat_slot_info sinfo;
325 int err;
326
Linus Torvalds8f593422008-05-19 19:53:01 -0700327 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 /*
329 * Check whether the directory is not in use, then check
330 * whether it is empty.
331 */
332 err = fat_dir_empty(inode);
333 if (err)
334 goto out;
335 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
336 if (err)
337 goto out;
338
339 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
340 if (err)
341 goto out;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700342 drop_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343
Dave Hansence71ec32006-09-30 23:29:06 -0700344 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 inode->i_ctime = CURRENT_TIME_SEC;
346 fat_detach(inode);
347out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700348 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700349 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700350 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351
352 return err;
353}
354
355/***** Make a directory */
356static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode)
357{
358 struct super_block *sb = dir->i_sb;
359 struct fat_slot_info sinfo;
360 struct inode *inode;
361 unsigned char msdos_name[MSDOS_NAME];
362 struct timespec ts;
363 int err, is_hid, cluster;
364
Linus Torvalds8f593422008-05-19 19:53:01 -0700365 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
367 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
368 msdos_name, &MSDOS_SB(sb)->options);
369 if (err)
370 goto out;
371 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
372 /* foo vs .foo situation */
373 if (!fat_scan(dir, msdos_name, &sinfo)) {
374 brelse(sinfo.bh);
375 err = -EINVAL;
376 goto out;
377 }
378
379 ts = CURRENT_TIME_SEC;
380 cluster = fat_alloc_new_dir(dir, &ts);
381 if (cluster < 0) {
382 err = cluster;
383 goto out;
384 }
385 err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &ts, &sinfo);
386 if (err)
387 goto out_free;
Dave Hansend8c76e62006-09-30 23:29:04 -0700388 inc_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389
390 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
391 brelse(sinfo.bh);
392 if (IS_ERR(inode)) {
393 err = PTR_ERR(inode);
394 /* the directory was completed, just return a error */
395 goto out;
396 }
397 inode->i_nlink = 2;
398 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
399 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
400
401 d_instantiate(dentry, inode);
402
Linus Torvalds8f593422008-05-19 19:53:01 -0700403 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700404 fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 return 0;
406
407out_free:
408 fat_free_clusters(dir, cluster);
409out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700410 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 return err;
412}
413
414/***** Unlink a file */
415static int msdos_unlink(struct inode *dir, struct dentry *dentry)
416{
417 struct inode *inode = dentry->d_inode;
Linus Torvalds8f593422008-05-19 19:53:01 -0700418 struct super_block *sb= inode->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 struct fat_slot_info sinfo;
420 int err;
421
Linus Torvalds8f593422008-05-19 19:53:01 -0700422 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
424 if (err)
425 goto out;
426
427 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
428 if (err)
429 goto out;
Dave Hansence71ec32006-09-30 23:29:06 -0700430 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 inode->i_ctime = CURRENT_TIME_SEC;
432 fat_detach(inode);
433out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700434 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700435 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700436 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
438 return err;
439}
440
441static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
442 struct dentry *old_dentry,
443 struct inode *new_dir, unsigned char *new_name,
444 struct dentry *new_dentry, int is_hid)
445{
446 struct buffer_head *dotdot_bh;
447 struct msdos_dir_entry *dotdot_de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 struct inode *old_inode, *new_inode;
449 struct fat_slot_info old_sinfo, sinfo;
450 struct timespec ts;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800451 loff_t dotdot_i_pos, new_i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 int err, old_attrs, is_dir, update_dotdot, corrupt = 0;
453
454 old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
455 old_inode = old_dentry->d_inode;
456 new_inode = new_dentry->d_inode;
457
458 err = fat_scan(old_dir, old_name, &old_sinfo);
459 if (err) {
460 err = -EIO;
461 goto out;
462 }
463
464 is_dir = S_ISDIR(old_inode->i_mode);
465 update_dotdot = (is_dir && old_dir != new_dir);
466 if (update_dotdot) {
467 if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de,
468 &dotdot_i_pos) < 0) {
469 err = -EIO;
470 goto out;
471 }
472 }
473
474 old_attrs = MSDOS_I(old_inode)->i_attrs;
475 err = fat_scan(new_dir, new_name, &sinfo);
476 if (!err) {
477 if (!new_inode) {
478 /* "foo" -> ".foo" case. just change the ATTR_HIDDEN */
479 if (sinfo.de != old_sinfo.de) {
480 err = -EINVAL;
481 goto out;
482 }
483 if (is_hid)
484 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
485 else
486 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
487 if (IS_DIRSYNC(old_dir)) {
488 err = fat_sync_inode(old_inode);
489 if (err) {
490 MSDOS_I(old_inode)->i_attrs = old_attrs;
491 goto out;
492 }
493 } else
494 mark_inode_dirty(old_inode);
495
496 old_dir->i_version++;
497 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
498 if (IS_DIRSYNC(old_dir))
499 (void)fat_sync_inode(old_dir);
500 else
501 mark_inode_dirty(old_dir);
502 goto out;
503 }
504 }
505
506 ts = CURRENT_TIME_SEC;
507 if (new_inode) {
508 if (err)
509 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 if (is_dir) {
511 err = fat_dir_empty(new_inode);
512 if (err)
513 goto out;
514 }
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800515 new_i_pos = MSDOS_I(new_inode)->i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 fat_detach(new_inode);
517 } else {
518 err = msdos_add_entry(new_dir, new_name, is_dir, is_hid, 0,
519 &ts, &sinfo);
520 if (err)
521 goto out;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800522 new_i_pos = sinfo.i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 }
524 new_dir->i_version++;
525
526 fat_detach(old_inode);
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800527 fat_attach(old_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 if (is_hid)
529 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
530 else
531 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
532 if (IS_DIRSYNC(new_dir)) {
533 err = fat_sync_inode(old_inode);
534 if (err)
535 goto error_inode;
536 } else
537 mark_inode_dirty(old_inode);
538
539 if (update_dotdot) {
540 int start = MSDOS_I(new_dir)->i_logstart;
541 dotdot_de->start = cpu_to_le16(start);
542 dotdot_de->starthi = cpu_to_le16(start >> 16);
543 mark_buffer_dirty(dotdot_bh);
544 if (IS_DIRSYNC(new_dir)) {
545 err = sync_dirty_buffer(dotdot_bh);
546 if (err)
547 goto error_dotdot;
548 }
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700549 drop_nlink(old_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 if (!new_inode)
Dave Hansend8c76e62006-09-30 23:29:04 -0700551 inc_nlink(new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 }
553
554 err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */
555 old_sinfo.bh = NULL;
556 if (err)
557 goto error_dotdot;
558 old_dir->i_version++;
559 old_dir->i_ctime = old_dir->i_mtime = ts;
560 if (IS_DIRSYNC(old_dir))
561 (void)fat_sync_inode(old_dir);
562 else
563 mark_inode_dirty(old_dir);
564
565 if (new_inode) {
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700566 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 if (is_dir)
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700568 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 new_inode->i_ctime = ts;
570 }
571out:
572 brelse(sinfo.bh);
573 brelse(dotdot_bh);
574 brelse(old_sinfo.bh);
575 return err;
576
577error_dotdot:
578 /* data cluster is shared, serious corruption */
579 corrupt = 1;
580
581 if (update_dotdot) {
582 int start = MSDOS_I(old_dir)->i_logstart;
583 dotdot_de->start = cpu_to_le16(start);
584 dotdot_de->starthi = cpu_to_le16(start >> 16);
585 mark_buffer_dirty(dotdot_bh);
586 corrupt |= sync_dirty_buffer(dotdot_bh);
587 }
588error_inode:
589 fat_detach(old_inode);
590 fat_attach(old_inode, old_sinfo.i_pos);
591 MSDOS_I(old_inode)->i_attrs = old_attrs;
592 if (new_inode) {
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800593 fat_attach(new_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594 if (corrupt)
595 corrupt |= fat_sync_inode(new_inode);
596 } else {
597 /*
598 * If new entry was not sharing the data cluster, it
599 * shouldn't be serious corruption.
600 */
601 int err2 = fat_remove_entries(new_dir, &sinfo);
602 if (corrupt)
603 corrupt |= err2;
604 sinfo.bh = NULL;
605 }
606 if (corrupt < 0) {
607 fat_fs_panic(new_dir->i_sb,
608 "%s: Filesystem corrupted (i_pos %lld)",
Harvey Harrison8e24eea2008-04-30 00:55:09 -0700609 __func__, sinfo.i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 }
611 goto out;
612}
613
614/***** Rename, a wrapper for rename_same_dir & rename_diff_dir */
615static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
616 struct inode *new_dir, struct dentry *new_dentry)
617{
Linus Torvalds8f593422008-05-19 19:53:01 -0700618 struct super_block *sb = old_dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
620 int err, is_hid;
621
Linus Torvalds8f593422008-05-19 19:53:01 -0700622 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623
624 err = msdos_format_name(old_dentry->d_name.name,
625 old_dentry->d_name.len, old_msdos_name,
626 &MSDOS_SB(old_dir->i_sb)->options);
627 if (err)
628 goto out;
629 err = msdos_format_name(new_dentry->d_name.name,
630 new_dentry->d_name.len, new_msdos_name,
631 &MSDOS_SB(new_dir->i_sb)->options);
632 if (err)
633 goto out;
634
635 is_hid =
636 (new_dentry->d_name.name[0] == '.') && (new_msdos_name[0] != '.');
637
638 err = do_msdos_rename(old_dir, old_msdos_name, old_dentry,
639 new_dir, new_msdos_name, new_dentry, is_hid);
640out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700641 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700642 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700643 err = fat_flush_inodes(sb, old_dir, new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 return err;
645}
646
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -0800647static const struct inode_operations msdos_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 .create = msdos_create,
649 .lookup = msdos_lookup,
650 .unlink = msdos_unlink,
651 .mkdir = msdos_mkdir,
652 .rmdir = msdos_rmdir,
653 .rename = msdos_rename,
OGAWA Hirofumi1278fdd2008-04-28 02:16:25 -0700654 .setattr = fat_setattr,
OGAWA Hirofumida63fc72006-11-16 01:19:28 -0800655 .getattr = fat_getattr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656};
657
658static int msdos_fill_super(struct super_block *sb, void *data, int silent)
659{
660 int res;
661
662 res = fat_fill_super(sb, data, silent, &msdos_dir_inode_operations, 0);
663 if (res)
664 return res;
665
666 sb->s_flags |= MS_NOATIME;
667 sb->s_root->d_op = &msdos_dentry_operations;
668 return 0;
669}
670
David Howells454e2392006-06-23 02:02:57 -0700671static int msdos_get_sb(struct file_system_type *fs_type,
672 int flags, const char *dev_name,
673 void *data, struct vfsmount *mnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674{
David Howells454e2392006-06-23 02:02:57 -0700675 return get_sb_bdev(fs_type, flags, dev_name, data, msdos_fill_super,
676 mnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677}
678
679static struct file_system_type msdos_fs_type = {
680 .owner = THIS_MODULE,
681 .name = "msdos",
682 .get_sb = msdos_get_sb,
683 .kill_sb = kill_block_super,
684 .fs_flags = FS_REQUIRES_DEV,
685};
686
687static int __init init_msdos_fs(void)
688{
689 return register_filesystem(&msdos_fs_type);
690}
691
692static void __exit exit_msdos_fs(void)
693{
694 unregister_filesystem(&msdos_fs_type);
695}
696
697MODULE_LICENSE("GPL");
698MODULE_AUTHOR("Werner Almesberger");
699MODULE_DESCRIPTION("MS-DOS filesystem support");
700
701module_init(init_msdos_fs)
702module_exit(exit_msdos_fs)