blob: 66e83b84545572d86e07ee7c8a3470f2641a007f [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>
OGAWA Hirofumi9e975da2008-11-06 12:53:46 -080012#include "fat.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070013
Linus Torvalds1da177e2005-04-16 15:20:36 -070014/* Characters that are undesirable in an MS-DOS file name */
15static unsigned char bad_chars[] = "*?<>|\"";
Rene Scharfe7557bc62008-07-25 01:46:45 -070016static unsigned char bad_if_strict[] = "+=,; ";
Linus Torvalds1da177e2005-04-16 15:20:36 -070017
18/***** Formats an MS-DOS file name. Rejects invalid names. */
19static int msdos_format_name(const unsigned char *name, int len,
20 unsigned char *res, struct fat_mount_options *opts)
21 /*
22 * name is the proposed name, len is its length, res is
23 * the resulting name, opts->name_check is either (r)elaxed,
24 * (n)ormal or (s)trict, opts->dotsOK allows dots at the
25 * beginning of name (for hidden files)
26 */
27{
28 unsigned char *walk;
Linus Torvalds1da177e2005-04-16 15:20:36 -070029 unsigned char c;
30 int space;
31
32 if (name[0] == '.') { /* dotfile because . and .. already done */
33 if (opts->dotsOK) {
34 /* Get rid of dot - test for it elsewhere */
35 name++;
36 len--;
Rene Scharfe7557bc62008-07-25 01:46:45 -070037 } else
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 return -EINVAL;
39 }
40 /*
Rene Scharfe7557bc62008-07-25 01:46:45 -070041 * disallow names that _really_ start with a dot
Linus Torvalds1da177e2005-04-16 15:20:36 -070042 */
Rene Scharfe7557bc62008-07-25 01:46:45 -070043 space = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044 c = 0;
45 for (walk = res; len && walk - res < 8; walk++) {
46 c = *name++;
47 len--;
48 if (opts->name_check != 'r' && strchr(bad_chars, c))
49 return -EINVAL;
Rene Scharfe7557bc62008-07-25 01:46:45 -070050 if (opts->name_check == 's' && strchr(bad_if_strict, c))
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 return -EINVAL;
52 if (c >= 'A' && c <= 'Z' && opts->name_check == 's')
53 return -EINVAL;
54 if (c < ' ' || c == ':' || c == '\\')
55 return -EINVAL;
56 /*
57 * 0xE5 is legal as a first character, but we must substitute
58 * 0x05 because 0xE5 marks deleted files. Yes, DOS really
59 * does this.
60 * It seems that Microsoft hacked DOS to support non-US
61 * characters after the 0xE5 character was already in use to
62 * mark deleted files.
63 */
64 if ((res == walk) && (c == 0xE5))
65 c = 0x05;
66 if (c == '.')
67 break;
68 space = (c == ' ');
69 *walk = (!opts->nocase && c >= 'a' && c <= 'z') ? c - 32 : c;
70 }
71 if (space)
72 return -EINVAL;
73 if (opts->name_check == 's' && len && c != '.') {
74 c = *name++;
75 len--;
76 if (c != '.')
77 return -EINVAL;
78 }
79 while (c != '.' && len--)
80 c = *name++;
81 if (c == '.') {
82 while (walk - res < 8)
83 *walk++ = ' ';
84 while (len > 0 && walk - res < MSDOS_NAME) {
85 c = *name++;
86 len--;
87 if (opts->name_check != 'r' && strchr(bad_chars, c))
88 return -EINVAL;
89 if (opts->name_check == 's' &&
Rene Scharfe7557bc62008-07-25 01:46:45 -070090 strchr(bad_if_strict, c))
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 return -EINVAL;
92 if (c < ' ' || c == ':' || c == '\\')
93 return -EINVAL;
94 if (c == '.') {
95 if (opts->name_check == 's')
96 return -EINVAL;
97 break;
98 }
99 if (c >= 'A' && c <= 'Z' && opts->name_check == 's')
100 return -EINVAL;
101 space = c == ' ';
102 if (!opts->nocase && c >= 'a' && c <= 'z')
103 *walk++ = c - 32;
104 else
105 *walk++ = c;
106 }
107 if (space)
108 return -EINVAL;
109 if (opts->name_check == 's' && len)
110 return -EINVAL;
111 }
112 while (walk - res < MSDOS_NAME)
113 *walk++ = ' ';
OGAWA Hirofumi094e3202006-03-31 02:30:53 -0800114
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 return 0;
116}
117
118/***** Locates a directory entry. Uses unformatted name. */
119static int msdos_find(struct inode *dir, const unsigned char *name, int len,
120 struct fat_slot_info *sinfo)
121{
122 struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
123 unsigned char msdos_name[MSDOS_NAME];
124 int err;
125
126 err = msdos_format_name(name, len, msdos_name, &sbi->options);
127 if (err)
128 return -ENOENT;
129
130 err = fat_scan(dir, msdos_name, sinfo);
131 if (!err && sbi->options.dotsOK) {
132 if (name[0] == '.') {
133 if (!(sinfo->de->attr & ATTR_HIDDEN))
134 err = -ENOENT;
135 } else {
136 if (sinfo->de->attr & ATTR_HIDDEN)
137 err = -ENOENT;
138 }
139 if (err)
140 brelse(sinfo->bh);
141 }
142 return err;
143}
144
145/*
146 * Compute the hash for the msdos name corresponding to the dentry.
147 * Note: if the name is invalid, we leave the hash code unchanged so
148 * that the existing dentry can be used. The msdos fs routines will
149 * return ENOENT or EINVAL as appropriate.
150 */
Nick Pigginb1e6a012011-01-07 17:49:28 +1100151static int msdos_hash(const struct dentry *dentry, const struct inode *inode,
152 struct qstr *qstr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153{
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 */
Nick Piggin621e1552011-01-07 17:49:27 +1100168static int msdos_cmp(const struct dentry *parent, const struct inode *pinode,
169 const struct dentry *dentry, const struct inode *inode,
170 unsigned int len, const char *str, const struct qstr *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171{
Nick Piggin621e1552011-01-07 17:49:27 +1100172 struct fat_mount_options *options = &MSDOS_SB(parent->d_sb)->options;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 unsigned char a_msdos_name[MSDOS_NAME], b_msdos_name[MSDOS_NAME];
174 int error;
175
Nick Piggin621e1552011-01-07 17:49:27 +1100176 error = msdos_format_name(name->name, name->len, a_msdos_name, options);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 if (error)
178 goto old_compare;
Nick Piggin621e1552011-01-07 17:49:27 +1100179 error = msdos_format_name(str, len, b_msdos_name, options);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 if (error)
181 goto old_compare;
182 error = memcmp(a_msdos_name, b_msdos_name, MSDOS_NAME);
183out:
184 return error;
185
186old_compare:
187 error = 1;
Nick Piggin621e1552011-01-07 17:49:27 +1100188 if (name->len == len)
189 error = memcmp(name->name, str, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 goto out;
191}
192
Al Viroce6cdc42009-02-20 05:59:46 +0000193static const struct dentry_operations msdos_dentry_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 .d_hash = msdos_hash,
195 .d_compare = msdos_cmp,
196};
197
198/*
199 * AV. Wrappers for FAT sb operations. Is it wise?
200 */
201
202/***** Get inode using directory and name */
203static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry,
204 struct nameidata *nd)
205{
206 struct super_block *sb = dir->i_sb;
207 struct fat_slot_info sinfo;
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800208 struct inode *inode;
209 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
Linus Torvalds8f593422008-05-19 19:53:01 -0700211 lock_super(sb);
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800212 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
Al Viroa9049372011-07-08 21:20:11 -0400213 switch (err) {
214 case -ENOENT:
215 inode = NULL;
216 break;
217 case 0:
218 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
219 brelse(sinfo.bh);
220 break;
221 default:
222 inode = ERR_PTR(err);
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800223 }
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800224 unlock_super(sb);
Al Viro3d239852010-12-18 10:44:00 -0500225 return d_splice_alias(inode, dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226}
227
228/***** Creates a directory entry (name is already formatted). */
229static int msdos_add_entry(struct inode *dir, const unsigned char *name,
230 int is_dir, int is_hid, int cluster,
231 struct timespec *ts, struct fat_slot_info *sinfo)
232{
Joe Petersonb271e062008-07-25 01:46:47 -0700233 struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 struct msdos_dir_entry de;
235 __le16 time, date;
236 int err;
237
238 memcpy(de.name, name, MSDOS_NAME);
239 de.attr = is_dir ? ATTR_DIR : ATTR_ARCH;
240 if (is_hid)
241 de.attr |= ATTR_HIDDEN;
242 de.lcase = 0;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800243 fat_time_unix2fat(sbi, ts, &time, &date, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 de.cdate = de.adate = 0;
245 de.ctime = 0;
246 de.ctime_cs = 0;
247 de.time = time;
248 de.date = date;
249 de.start = cpu_to_le16(cluster);
250 de.starthi = cpu_to_le16(cluster >> 16);
251 de.size = 0;
252
253 err = fat_add_entries(dir, &de, 1, sinfo);
254 if (err)
255 return err;
256
257 dir->i_ctime = dir->i_mtime = *ts;
258 if (IS_DIRSYNC(dir))
259 (void)fat_sync_inode(dir);
260 else
261 mark_inode_dirty(dir);
262
263 return 0;
264}
265
266/***** Create a file */
267static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
268 struct nameidata *nd)
269{
270 struct super_block *sb = dir->i_sb;
Chris Masonae78bf92006-09-29 02:00:03 -0700271 struct inode *inode = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 struct fat_slot_info sinfo;
273 struct timespec ts;
274 unsigned char msdos_name[MSDOS_NAME];
275 int err, is_hid;
276
Linus Torvalds8f593422008-05-19 19:53:01 -0700277 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278
279 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
280 msdos_name, &MSDOS_SB(sb)->options);
281 if (err)
282 goto out;
283 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
284 /* Have to do it due to foo vs. .foo conflicts */
285 if (!fat_scan(dir, msdos_name, &sinfo)) {
286 brelse(sinfo.bh);
287 err = -EINVAL;
288 goto out;
289 }
290
291 ts = CURRENT_TIME_SEC;
292 err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &ts, &sinfo);
293 if (err)
294 goto out;
295 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
296 brelse(sinfo.bh);
297 if (IS_ERR(inode)) {
298 err = PTR_ERR(inode);
299 goto out;
300 }
301 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
302 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
303
304 d_instantiate(dentry, inode);
305out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700306 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700307 if (!err)
308 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 return err;
310}
311
312/***** Remove a directory */
313static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
314{
Linus Torvalds8f593422008-05-19 19:53:01 -0700315 struct super_block *sb = dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 struct inode *inode = dentry->d_inode;
317 struct fat_slot_info sinfo;
318 int err;
319
Linus Torvalds8f593422008-05-19 19:53:01 -0700320 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 /*
322 * Check whether the directory is not in use, then check
323 * whether it is empty.
324 */
325 err = fat_dir_empty(inode);
326 if (err)
327 goto out;
328 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
329 if (err)
330 goto out;
331
332 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
333 if (err)
334 goto out;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700335 drop_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336
Dave Hansence71ec32006-09-30 23:29:06 -0700337 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 inode->i_ctime = CURRENT_TIME_SEC;
339 fat_detach(inode);
340out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700341 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700342 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700343 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344
345 return err;
346}
347
348/***** Make a directory */
349static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode)
350{
351 struct super_block *sb = dir->i_sb;
352 struct fat_slot_info sinfo;
353 struct inode *inode;
354 unsigned char msdos_name[MSDOS_NAME];
355 struct timespec ts;
356 int err, is_hid, cluster;
357
Linus Torvalds8f593422008-05-19 19:53:01 -0700358 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
360 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
361 msdos_name, &MSDOS_SB(sb)->options);
362 if (err)
363 goto out;
364 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
365 /* foo vs .foo situation */
366 if (!fat_scan(dir, msdos_name, &sinfo)) {
367 brelse(sinfo.bh);
368 err = -EINVAL;
369 goto out;
370 }
371
372 ts = CURRENT_TIME_SEC;
373 cluster = fat_alloc_new_dir(dir, &ts);
374 if (cluster < 0) {
375 err = cluster;
376 goto out;
377 }
378 err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &ts, &sinfo);
379 if (err)
380 goto out_free;
Dave Hansend8c76e62006-09-30 23:29:04 -0700381 inc_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
383 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
384 brelse(sinfo.bh);
385 if (IS_ERR(inode)) {
386 err = PTR_ERR(inode);
387 /* the directory was completed, just return a error */
388 goto out;
389 }
390 inode->i_nlink = 2;
391 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
392 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
393
394 d_instantiate(dentry, inode);
395
Linus Torvalds8f593422008-05-19 19:53:01 -0700396 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700397 fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 return 0;
399
400out_free:
401 fat_free_clusters(dir, cluster);
402out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700403 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 return err;
405}
406
407/***** Unlink a file */
408static int msdos_unlink(struct inode *dir, struct dentry *dentry)
409{
410 struct inode *inode = dentry->d_inode;
Linus Torvalds8f593422008-05-19 19:53:01 -0700411 struct super_block *sb= inode->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 struct fat_slot_info sinfo;
413 int err;
414
Linus Torvalds8f593422008-05-19 19:53:01 -0700415 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
417 if (err)
418 goto out;
419
420 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
421 if (err)
422 goto out;
Dave Hansence71ec32006-09-30 23:29:06 -0700423 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 inode->i_ctime = CURRENT_TIME_SEC;
425 fat_detach(inode);
426out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700427 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700428 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700429 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430
431 return err;
432}
433
434static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
435 struct dentry *old_dentry,
436 struct inode *new_dir, unsigned char *new_name,
437 struct dentry *new_dentry, int is_hid)
438{
439 struct buffer_head *dotdot_bh;
440 struct msdos_dir_entry *dotdot_de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 struct inode *old_inode, *new_inode;
442 struct fat_slot_info old_sinfo, sinfo;
443 struct timespec ts;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800444 loff_t dotdot_i_pos, new_i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 int err, old_attrs, is_dir, update_dotdot, corrupt = 0;
446
447 old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
448 old_inode = old_dentry->d_inode;
449 new_inode = new_dentry->d_inode;
450
451 err = fat_scan(old_dir, old_name, &old_sinfo);
452 if (err) {
453 err = -EIO;
454 goto out;
455 }
456
457 is_dir = S_ISDIR(old_inode->i_mode);
458 update_dotdot = (is_dir && old_dir != new_dir);
459 if (update_dotdot) {
460 if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de,
461 &dotdot_i_pos) < 0) {
462 err = -EIO;
463 goto out;
464 }
465 }
466
467 old_attrs = MSDOS_I(old_inode)->i_attrs;
468 err = fat_scan(new_dir, new_name, &sinfo);
469 if (!err) {
470 if (!new_inode) {
471 /* "foo" -> ".foo" case. just change the ATTR_HIDDEN */
472 if (sinfo.de != old_sinfo.de) {
473 err = -EINVAL;
474 goto out;
475 }
476 if (is_hid)
477 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
478 else
479 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
480 if (IS_DIRSYNC(old_dir)) {
481 err = fat_sync_inode(old_inode);
482 if (err) {
483 MSDOS_I(old_inode)->i_attrs = old_attrs;
484 goto out;
485 }
486 } else
487 mark_inode_dirty(old_inode);
488
489 old_dir->i_version++;
490 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
491 if (IS_DIRSYNC(old_dir))
492 (void)fat_sync_inode(old_dir);
493 else
494 mark_inode_dirty(old_dir);
495 goto out;
496 }
497 }
498
499 ts = CURRENT_TIME_SEC;
500 if (new_inode) {
501 if (err)
502 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 if (is_dir) {
504 err = fat_dir_empty(new_inode);
505 if (err)
506 goto out;
507 }
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800508 new_i_pos = MSDOS_I(new_inode)->i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509 fat_detach(new_inode);
510 } else {
511 err = msdos_add_entry(new_dir, new_name, is_dir, is_hid, 0,
512 &ts, &sinfo);
513 if (err)
514 goto out;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800515 new_i_pos = sinfo.i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 }
517 new_dir->i_version++;
518
519 fat_detach(old_inode);
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800520 fat_attach(old_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 if (is_hid)
522 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
523 else
524 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
525 if (IS_DIRSYNC(new_dir)) {
526 err = fat_sync_inode(old_inode);
527 if (err)
528 goto error_inode;
529 } else
530 mark_inode_dirty(old_inode);
531
532 if (update_dotdot) {
533 int start = MSDOS_I(new_dir)->i_logstart;
534 dotdot_de->start = cpu_to_le16(start);
535 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -0400536 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537 if (IS_DIRSYNC(new_dir)) {
538 err = sync_dirty_buffer(dotdot_bh);
539 if (err)
540 goto error_dotdot;
541 }
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700542 drop_nlink(old_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 if (!new_inode)
Dave Hansend8c76e62006-09-30 23:29:04 -0700544 inc_nlink(new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 }
546
547 err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */
548 old_sinfo.bh = NULL;
549 if (err)
550 goto error_dotdot;
551 old_dir->i_version++;
552 old_dir->i_ctime = old_dir->i_mtime = ts;
553 if (IS_DIRSYNC(old_dir))
554 (void)fat_sync_inode(old_dir);
555 else
556 mark_inode_dirty(old_dir);
557
558 if (new_inode) {
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700559 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 if (is_dir)
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700561 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 new_inode->i_ctime = ts;
563 }
564out:
565 brelse(sinfo.bh);
566 brelse(dotdot_bh);
567 brelse(old_sinfo.bh);
568 return err;
569
570error_dotdot:
571 /* data cluster is shared, serious corruption */
572 corrupt = 1;
573
574 if (update_dotdot) {
575 int start = MSDOS_I(old_dir)->i_logstart;
576 dotdot_de->start = cpu_to_le16(start);
577 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -0400578 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 corrupt |= sync_dirty_buffer(dotdot_bh);
580 }
581error_inode:
582 fat_detach(old_inode);
583 fat_attach(old_inode, old_sinfo.i_pos);
584 MSDOS_I(old_inode)->i_attrs = old_attrs;
585 if (new_inode) {
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800586 fat_attach(new_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 if (corrupt)
588 corrupt |= fat_sync_inode(new_inode);
589 } else {
590 /*
591 * If new entry was not sharing the data cluster, it
592 * shouldn't be serious corruption.
593 */
594 int err2 = fat_remove_entries(new_dir, &sinfo);
595 if (corrupt)
596 corrupt |= err2;
597 sinfo.bh = NULL;
598 }
599 if (corrupt < 0) {
Denis Karpov85c78592009-06-04 02:34:22 +0900600 fat_fs_error(new_dir->i_sb,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 "%s: Filesystem corrupted (i_pos %lld)",
Harvey Harrison8e24eea2008-04-30 00:55:09 -0700602 __func__, sinfo.i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 }
604 goto out;
605}
606
607/***** Rename, a wrapper for rename_same_dir & rename_diff_dir */
608static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
609 struct inode *new_dir, struct dentry *new_dentry)
610{
Linus Torvalds8f593422008-05-19 19:53:01 -0700611 struct super_block *sb = old_dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
613 int err, is_hid;
614
Linus Torvalds8f593422008-05-19 19:53:01 -0700615 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616
617 err = msdos_format_name(old_dentry->d_name.name,
618 old_dentry->d_name.len, old_msdos_name,
619 &MSDOS_SB(old_dir->i_sb)->options);
620 if (err)
621 goto out;
622 err = msdos_format_name(new_dentry->d_name.name,
623 new_dentry->d_name.len, new_msdos_name,
624 &MSDOS_SB(new_dir->i_sb)->options);
625 if (err)
626 goto out;
627
628 is_hid =
629 (new_dentry->d_name.name[0] == '.') && (new_msdos_name[0] != '.');
630
631 err = do_msdos_rename(old_dir, old_msdos_name, old_dentry,
632 new_dir, new_msdos_name, new_dentry, is_hid);
633out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700634 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700635 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700636 err = fat_flush_inodes(sb, old_dir, new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 return err;
638}
639
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -0800640static const struct inode_operations msdos_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 .create = msdos_create,
642 .lookup = msdos_lookup,
643 .unlink = msdos_unlink,
644 .mkdir = msdos_mkdir,
645 .rmdir = msdos_rmdir,
646 .rename = msdos_rename,
OGAWA Hirofumi1278fdd2008-04-28 02:16:25 -0700647 .setattr = fat_setattr,
OGAWA Hirofumida63fc72006-11-16 01:19:28 -0800648 .getattr = fat_getattr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649};
650
Al Viro3d239852010-12-18 10:44:00 -0500651static void setup(struct super_block *sb)
652{
OGAWA Hirofumi384f5c92011-04-12 21:08:37 +0900653 MSDOS_SB(sb)->dir_ops = &msdos_dir_inode_operations;
Al Viro3d239852010-12-18 10:44:00 -0500654 sb->s_d_op = &msdos_dentry_operations;
655 sb->s_flags |= MS_NOATIME;
656}
657
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658static int msdos_fill_super(struct super_block *sb, void *data, int silent)
659{
OGAWA Hirofumi384f5c92011-04-12 21:08:37 +0900660 return fat_fill_super(sb, data, silent, 0, setup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661}
662
Al Viro152a0832010-07-25 00:46:55 +0400663static struct dentry *msdos_mount(struct file_system_type *fs_type,
David Howells454e2392006-06-23 02:02:57 -0700664 int flags, const char *dev_name,
Al Viro152a0832010-07-25 00:46:55 +0400665 void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666{
Al Viro152a0832010-07-25 00:46:55 +0400667 return mount_bdev(fs_type, flags, dev_name, data, msdos_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668}
669
670static struct file_system_type msdos_fs_type = {
671 .owner = THIS_MODULE,
672 .name = "msdos",
Al Viro152a0832010-07-25 00:46:55 +0400673 .mount = msdos_mount,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 .kill_sb = kill_block_super,
675 .fs_flags = FS_REQUIRES_DEV,
676};
677
678static int __init init_msdos_fs(void)
679{
680 return register_filesystem(&msdos_fs_type);
681}
682
683static void __exit exit_msdos_fs(void)
684{
685 unregister_filesystem(&msdos_fs_type);
686}
687
688MODULE_LICENSE("GPL");
689MODULE_AUTHOR("Werner Almesberger");
690MODULE_DESCRIPTION("MS-DOS filesystem support");
691
692module_init(init_msdos_fs)
693module_exit(exit_msdos_fs)