blob: 3345aabd1dd7e32585b18956175265ec3fdda011 [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 */
151static int msdos_hash(struct dentry *dentry, struct qstr *qstr)
152{
153 struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;
154 unsigned char msdos_name[MSDOS_NAME];
155 int error;
156
157 error = msdos_format_name(qstr->name, qstr->len, msdos_name, options);
158 if (!error)
159 qstr->hash = full_name_hash(msdos_name, MSDOS_NAME);
160 return 0;
161}
162
163/*
164 * Compare two msdos names. If either of the names are invalid,
165 * we fall back to doing the standard name comparison.
166 */
167static int msdos_cmp(struct dentry *dentry, struct qstr *a, struct qstr *b)
168{
169 struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options;
170 unsigned char a_msdos_name[MSDOS_NAME], b_msdos_name[MSDOS_NAME];
171 int error;
172
173 error = msdos_format_name(a->name, a->len, a_msdos_name, options);
174 if (error)
175 goto old_compare;
176 error = msdos_format_name(b->name, b->len, b_msdos_name, options);
177 if (error)
178 goto old_compare;
179 error = memcmp(a_msdos_name, b_msdos_name, MSDOS_NAME);
180out:
181 return error;
182
183old_compare:
184 error = 1;
185 if (a->len == b->len)
186 error = memcmp(a->name, b->name, a->len);
187 goto out;
188}
189
Al Viroce6cdc42009-02-20 05:59:46 +0000190static const struct dentry_operations msdos_dentry_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 .d_hash = msdos_hash,
192 .d_compare = msdos_cmp,
193};
194
195/*
196 * AV. Wrappers for FAT sb operations. Is it wise?
197 */
198
199/***** Get inode using directory and name */
200static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry,
201 struct nameidata *nd)
202{
203 struct super_block *sb = dir->i_sb;
204 struct fat_slot_info sinfo;
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800205 struct inode *inode;
206 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207
Linus Torvalds8f593422008-05-19 19:53:01 -0700208 lock_super(sb);
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800209
210 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
211 if (err) {
212 if (err == -ENOENT) {
213 inode = NULL;
214 goto out;
215 }
216 goto error;
217 }
218
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
220 brelse(sinfo.bh);
221 if (IS_ERR(inode)) {
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800222 err = PTR_ERR(inode);
223 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 }
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800225out:
226 unlock_super(sb);
227 dentry->d_op = &msdos_dentry_operations;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 dentry = d_splice_alias(inode, dentry);
229 if (dentry)
230 dentry->d_op = &msdos_dentry_operations;
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800231 return dentry;
232
233error:
Linus Torvalds8f593422008-05-19 19:53:01 -0700234 unlock_super(sb);
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800235 return ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236}
237
238/***** Creates a directory entry (name is already formatted). */
239static int msdos_add_entry(struct inode *dir, const unsigned char *name,
240 int is_dir, int is_hid, int cluster,
241 struct timespec *ts, struct fat_slot_info *sinfo)
242{
Joe Petersonb271e062008-07-25 01:46:47 -0700243 struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 struct msdos_dir_entry de;
245 __le16 time, date;
246 int err;
247
248 memcpy(de.name, name, MSDOS_NAME);
249 de.attr = is_dir ? ATTR_DIR : ATTR_ARCH;
250 if (is_hid)
251 de.attr |= ATTR_HIDDEN;
252 de.lcase = 0;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800253 fat_time_unix2fat(sbi, ts, &time, &date, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 de.cdate = de.adate = 0;
255 de.ctime = 0;
256 de.ctime_cs = 0;
257 de.time = time;
258 de.date = date;
259 de.start = cpu_to_le16(cluster);
260 de.starthi = cpu_to_le16(cluster >> 16);
261 de.size = 0;
262
263 err = fat_add_entries(dir, &de, 1, sinfo);
264 if (err)
265 return err;
266
267 dir->i_ctime = dir->i_mtime = *ts;
268 if (IS_DIRSYNC(dir))
269 (void)fat_sync_inode(dir);
270 else
271 mark_inode_dirty(dir);
272
273 return 0;
274}
275
276/***** Create a file */
277static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
278 struct nameidata *nd)
279{
280 struct super_block *sb = dir->i_sb;
Chris Masonae78bf92006-09-29 02:00:03 -0700281 struct inode *inode = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 struct fat_slot_info sinfo;
283 struct timespec ts;
284 unsigned char msdos_name[MSDOS_NAME];
285 int err, is_hid;
286
Linus Torvalds8f593422008-05-19 19:53:01 -0700287 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288
289 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
290 msdos_name, &MSDOS_SB(sb)->options);
291 if (err)
292 goto out;
293 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
294 /* Have to do it due to foo vs. .foo conflicts */
295 if (!fat_scan(dir, msdos_name, &sinfo)) {
296 brelse(sinfo.bh);
297 err = -EINVAL;
298 goto out;
299 }
300
301 ts = CURRENT_TIME_SEC;
302 err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &ts, &sinfo);
303 if (err)
304 goto out;
305 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
306 brelse(sinfo.bh);
307 if (IS_ERR(inode)) {
308 err = PTR_ERR(inode);
309 goto out;
310 }
311 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
312 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
313
314 d_instantiate(dentry, inode);
315out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700316 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700317 if (!err)
318 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 return err;
320}
321
322/***** Remove a directory */
323static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
324{
Linus Torvalds8f593422008-05-19 19:53:01 -0700325 struct super_block *sb = dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 struct inode *inode = dentry->d_inode;
327 struct fat_slot_info sinfo;
328 int err;
329
Linus Torvalds8f593422008-05-19 19:53:01 -0700330 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 /*
332 * Check whether the directory is not in use, then check
333 * whether it is empty.
334 */
335 err = fat_dir_empty(inode);
336 if (err)
337 goto out;
338 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
339 if (err)
340 goto out;
341
342 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
343 if (err)
344 goto out;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700345 drop_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346
Dave Hansence71ec32006-09-30 23:29:06 -0700347 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 inode->i_ctime = CURRENT_TIME_SEC;
349 fat_detach(inode);
350out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700351 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700352 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700353 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354
355 return err;
356}
357
358/***** Make a directory */
359static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode)
360{
361 struct super_block *sb = dir->i_sb;
362 struct fat_slot_info sinfo;
363 struct inode *inode;
364 unsigned char msdos_name[MSDOS_NAME];
365 struct timespec ts;
366 int err, is_hid, cluster;
367
Linus Torvalds8f593422008-05-19 19:53:01 -0700368 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369
370 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
371 msdos_name, &MSDOS_SB(sb)->options);
372 if (err)
373 goto out;
374 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
375 /* foo vs .foo situation */
376 if (!fat_scan(dir, msdos_name, &sinfo)) {
377 brelse(sinfo.bh);
378 err = -EINVAL;
379 goto out;
380 }
381
382 ts = CURRENT_TIME_SEC;
383 cluster = fat_alloc_new_dir(dir, &ts);
384 if (cluster < 0) {
385 err = cluster;
386 goto out;
387 }
388 err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &ts, &sinfo);
389 if (err)
390 goto out_free;
Dave Hansend8c76e62006-09-30 23:29:04 -0700391 inc_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
393 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
394 brelse(sinfo.bh);
395 if (IS_ERR(inode)) {
396 err = PTR_ERR(inode);
397 /* the directory was completed, just return a error */
398 goto out;
399 }
400 inode->i_nlink = 2;
401 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
402 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
403
404 d_instantiate(dentry, inode);
405
Linus Torvalds8f593422008-05-19 19:53:01 -0700406 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700407 fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 return 0;
409
410out_free:
411 fat_free_clusters(dir, cluster);
412out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700413 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 return err;
415}
416
417/***** Unlink a file */
418static int msdos_unlink(struct inode *dir, struct dentry *dentry)
419{
420 struct inode *inode = dentry->d_inode;
Linus Torvalds8f593422008-05-19 19:53:01 -0700421 struct super_block *sb= inode->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 struct fat_slot_info sinfo;
423 int err;
424
Linus Torvalds8f593422008-05-19 19:53:01 -0700425 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
427 if (err)
428 goto out;
429
430 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
431 if (err)
432 goto out;
Dave Hansence71ec32006-09-30 23:29:06 -0700433 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 inode->i_ctime = CURRENT_TIME_SEC;
435 fat_detach(inode);
436out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700437 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700438 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700439 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440
441 return err;
442}
443
444static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
445 struct dentry *old_dentry,
446 struct inode *new_dir, unsigned char *new_name,
447 struct dentry *new_dentry, int is_hid)
448{
449 struct buffer_head *dotdot_bh;
450 struct msdos_dir_entry *dotdot_de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 struct inode *old_inode, *new_inode;
452 struct fat_slot_info old_sinfo, sinfo;
453 struct timespec ts;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800454 loff_t dotdot_i_pos, new_i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 int err, old_attrs, is_dir, update_dotdot, corrupt = 0;
456
457 old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
458 old_inode = old_dentry->d_inode;
459 new_inode = new_dentry->d_inode;
460
461 err = fat_scan(old_dir, old_name, &old_sinfo);
462 if (err) {
463 err = -EIO;
464 goto out;
465 }
466
467 is_dir = S_ISDIR(old_inode->i_mode);
468 update_dotdot = (is_dir && old_dir != new_dir);
469 if (update_dotdot) {
470 if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de,
471 &dotdot_i_pos) < 0) {
472 err = -EIO;
473 goto out;
474 }
475 }
476
477 old_attrs = MSDOS_I(old_inode)->i_attrs;
478 err = fat_scan(new_dir, new_name, &sinfo);
479 if (!err) {
480 if (!new_inode) {
481 /* "foo" -> ".foo" case. just change the ATTR_HIDDEN */
482 if (sinfo.de != old_sinfo.de) {
483 err = -EINVAL;
484 goto out;
485 }
486 if (is_hid)
487 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
488 else
489 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
490 if (IS_DIRSYNC(old_dir)) {
491 err = fat_sync_inode(old_inode);
492 if (err) {
493 MSDOS_I(old_inode)->i_attrs = old_attrs;
494 goto out;
495 }
496 } else
497 mark_inode_dirty(old_inode);
498
499 old_dir->i_version++;
500 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
501 if (IS_DIRSYNC(old_dir))
502 (void)fat_sync_inode(old_dir);
503 else
504 mark_inode_dirty(old_dir);
505 goto out;
506 }
507 }
508
509 ts = CURRENT_TIME_SEC;
510 if (new_inode) {
511 if (err)
512 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 if (is_dir) {
514 err = fat_dir_empty(new_inode);
515 if (err)
516 goto out;
517 }
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800518 new_i_pos = MSDOS_I(new_inode)->i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 fat_detach(new_inode);
520 } else {
521 err = msdos_add_entry(new_dir, new_name, is_dir, is_hid, 0,
522 &ts, &sinfo);
523 if (err)
524 goto out;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800525 new_i_pos = sinfo.i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 }
527 new_dir->i_version++;
528
529 fat_detach(old_inode);
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800530 fat_attach(old_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 if (is_hid)
532 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
533 else
534 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
535 if (IS_DIRSYNC(new_dir)) {
536 err = fat_sync_inode(old_inode);
537 if (err)
538 goto error_inode;
539 } else
540 mark_inode_dirty(old_inode);
541
542 if (update_dotdot) {
543 int start = MSDOS_I(new_dir)->i_logstart;
544 dotdot_de->start = cpu_to_le16(start);
545 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -0400546 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 if (IS_DIRSYNC(new_dir)) {
548 err = sync_dirty_buffer(dotdot_bh);
549 if (err)
550 goto error_dotdot;
551 }
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700552 drop_nlink(old_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 if (!new_inode)
Dave Hansend8c76e62006-09-30 23:29:04 -0700554 inc_nlink(new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 }
556
557 err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */
558 old_sinfo.bh = NULL;
559 if (err)
560 goto error_dotdot;
561 old_dir->i_version++;
562 old_dir->i_ctime = old_dir->i_mtime = ts;
563 if (IS_DIRSYNC(old_dir))
564 (void)fat_sync_inode(old_dir);
565 else
566 mark_inode_dirty(old_dir);
567
568 if (new_inode) {
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700569 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 if (is_dir)
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700571 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 new_inode->i_ctime = ts;
573 }
574out:
575 brelse(sinfo.bh);
576 brelse(dotdot_bh);
577 brelse(old_sinfo.bh);
578 return err;
579
580error_dotdot:
581 /* data cluster is shared, serious corruption */
582 corrupt = 1;
583
584 if (update_dotdot) {
585 int start = MSDOS_I(old_dir)->i_logstart;
586 dotdot_de->start = cpu_to_le16(start);
587 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -0400588 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 corrupt |= sync_dirty_buffer(dotdot_bh);
590 }
591error_inode:
592 fat_detach(old_inode);
593 fat_attach(old_inode, old_sinfo.i_pos);
594 MSDOS_I(old_inode)->i_attrs = old_attrs;
595 if (new_inode) {
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800596 fat_attach(new_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 if (corrupt)
598 corrupt |= fat_sync_inode(new_inode);
599 } else {
600 /*
601 * If new entry was not sharing the data cluster, it
602 * shouldn't be serious corruption.
603 */
604 int err2 = fat_remove_entries(new_dir, &sinfo);
605 if (corrupt)
606 corrupt |= err2;
607 sinfo.bh = NULL;
608 }
609 if (corrupt < 0) {
Denis Karpov85c78592009-06-04 02:34:22 +0900610 fat_fs_error(new_dir->i_sb,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 "%s: Filesystem corrupted (i_pos %lld)",
Harvey Harrison8e24eea2008-04-30 00:55:09 -0700612 __func__, sinfo.i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 }
614 goto out;
615}
616
617/***** Rename, a wrapper for rename_same_dir & rename_diff_dir */
618static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
619 struct inode *new_dir, struct dentry *new_dentry)
620{
Linus Torvalds8f593422008-05-19 19:53:01 -0700621 struct super_block *sb = old_dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
623 int err, is_hid;
624
Linus Torvalds8f593422008-05-19 19:53:01 -0700625 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626
627 err = msdos_format_name(old_dentry->d_name.name,
628 old_dentry->d_name.len, old_msdos_name,
629 &MSDOS_SB(old_dir->i_sb)->options);
630 if (err)
631 goto out;
632 err = msdos_format_name(new_dentry->d_name.name,
633 new_dentry->d_name.len, new_msdos_name,
634 &MSDOS_SB(new_dir->i_sb)->options);
635 if (err)
636 goto out;
637
638 is_hid =
639 (new_dentry->d_name.name[0] == '.') && (new_msdos_name[0] != '.');
640
641 err = do_msdos_rename(old_dir, old_msdos_name, old_dentry,
642 new_dir, new_msdos_name, new_dentry, is_hid);
643out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700644 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700645 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700646 err = fat_flush_inodes(sb, old_dir, new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 return err;
648}
649
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -0800650static const struct inode_operations msdos_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 .create = msdos_create,
652 .lookup = msdos_lookup,
653 .unlink = msdos_unlink,
654 .mkdir = msdos_mkdir,
655 .rmdir = msdos_rmdir,
656 .rename = msdos_rename,
OGAWA Hirofumi1278fdd2008-04-28 02:16:25 -0700657 .setattr = fat_setattr,
OGAWA Hirofumida63fc72006-11-16 01:19:28 -0800658 .getattr = fat_getattr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659};
660
661static int msdos_fill_super(struct super_block *sb, void *data, int silent)
662{
663 int res;
664
Arnd Bergmann37687442010-09-14 23:07:27 +0200665 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 res = fat_fill_super(sb, data, silent, &msdos_dir_inode_operations, 0);
Jan Blunckdb719222010-08-15 22:51:10 +0200667 if (res) {
Arnd Bergmann37687442010-09-14 23:07:27 +0200668 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 return res;
Jan Blunckdb719222010-08-15 22:51:10 +0200670 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671
672 sb->s_flags |= MS_NOATIME;
673 sb->s_root->d_op = &msdos_dentry_operations;
Arnd Bergmann37687442010-09-14 23:07:27 +0200674 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675 return 0;
676}
677
Al Viro152a0832010-07-25 00:46:55 +0400678static struct dentry *msdos_mount(struct file_system_type *fs_type,
David Howells454e2392006-06-23 02:02:57 -0700679 int flags, const char *dev_name,
Al Viro152a0832010-07-25 00:46:55 +0400680 void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681{
Al Viro152a0832010-07-25 00:46:55 +0400682 return mount_bdev(fs_type, flags, dev_name, data, msdos_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683}
684
685static struct file_system_type msdos_fs_type = {
686 .owner = THIS_MODULE,
687 .name = "msdos",
Al Viro152a0832010-07-25 00:46:55 +0400688 .mount = msdos_mount,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 .kill_sb = kill_block_super,
690 .fs_flags = FS_REQUIRES_DEV,
691};
692
693static int __init init_msdos_fs(void)
694{
695 return register_filesystem(&msdos_fs_type);
696}
697
698static void __exit exit_msdos_fs(void)
699{
700 unregister_filesystem(&msdos_fs_type);
701}
702
703MODULE_LICENSE("GPL");
704MODULE_AUTHOR("Werner Almesberger");
705MODULE_DESCRIPTION("MS-DOS filesystem support");
706
707module_init(init_msdos_fs)
708module_exit(exit_msdos_fs)