blob: 711499040eb615ebe66a263f3d99661e9698e0b5 [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
213 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
214 if (err) {
215 if (err == -ENOENT) {
216 inode = NULL;
217 goto out;
218 }
219 goto error;
220 }
221
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
223 brelse(sinfo.bh);
224 if (IS_ERR(inode)) {
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800225 err = PTR_ERR(inode);
226 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 }
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800228out:
229 unlock_super(sb);
Al Viro3d239852010-12-18 10:44:00 -0500230 return d_splice_alias(inode, dentry);
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800231
232error:
Linus Torvalds8f593422008-05-19 19:53:01 -0700233 unlock_super(sb);
OGAWA Hirofumi45cfbe32008-11-06 12:53:53 -0800234 return ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235}
236
237/***** Creates a directory entry (name is already formatted). */
238static int msdos_add_entry(struct inode *dir, const unsigned char *name,
239 int is_dir, int is_hid, int cluster,
240 struct timespec *ts, struct fat_slot_info *sinfo)
241{
Joe Petersonb271e062008-07-25 01:46:47 -0700242 struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 struct msdos_dir_entry de;
244 __le16 time, date;
245 int err;
246
247 memcpy(de.name, name, MSDOS_NAME);
248 de.attr = is_dir ? ATTR_DIR : ATTR_ARCH;
249 if (is_hid)
250 de.attr |= ATTR_HIDDEN;
251 de.lcase = 0;
OGAWA Hirofumi7decd1c2008-11-06 12:53:47 -0800252 fat_time_unix2fat(sbi, ts, &time, &date, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 de.cdate = de.adate = 0;
254 de.ctime = 0;
255 de.ctime_cs = 0;
256 de.time = time;
257 de.date = date;
258 de.start = cpu_to_le16(cluster);
259 de.starthi = cpu_to_le16(cluster >> 16);
260 de.size = 0;
261
262 err = fat_add_entries(dir, &de, 1, sinfo);
263 if (err)
264 return err;
265
266 dir->i_ctime = dir->i_mtime = *ts;
267 if (IS_DIRSYNC(dir))
268 (void)fat_sync_inode(dir);
269 else
270 mark_inode_dirty(dir);
271
272 return 0;
273}
274
275/***** Create a file */
276static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
277 struct nameidata *nd)
278{
279 struct super_block *sb = dir->i_sb;
Chris Masonae78bf92006-09-29 02:00:03 -0700280 struct inode *inode = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 struct fat_slot_info sinfo;
282 struct timespec ts;
283 unsigned char msdos_name[MSDOS_NAME];
284 int err, is_hid;
285
Linus Torvalds8f593422008-05-19 19:53:01 -0700286 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287
288 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
289 msdos_name, &MSDOS_SB(sb)->options);
290 if (err)
291 goto out;
292 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
293 /* Have to do it due to foo vs. .foo conflicts */
294 if (!fat_scan(dir, msdos_name, &sinfo)) {
295 brelse(sinfo.bh);
296 err = -EINVAL;
297 goto out;
298 }
299
300 ts = CURRENT_TIME_SEC;
301 err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &ts, &sinfo);
302 if (err)
303 goto out;
304 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
305 brelse(sinfo.bh);
306 if (IS_ERR(inode)) {
307 err = PTR_ERR(inode);
308 goto out;
309 }
310 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
311 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
312
313 d_instantiate(dentry, inode);
314out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700315 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700316 if (!err)
317 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318 return err;
319}
320
321/***** Remove a directory */
322static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
323{
Linus Torvalds8f593422008-05-19 19:53:01 -0700324 struct super_block *sb = dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 struct inode *inode = dentry->d_inode;
326 struct fat_slot_info sinfo;
327 int err;
328
Linus Torvalds8f593422008-05-19 19:53:01 -0700329 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 /*
331 * Check whether the directory is not in use, then check
332 * whether it is empty.
333 */
334 err = fat_dir_empty(inode);
335 if (err)
336 goto out;
337 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
338 if (err)
339 goto out;
340
341 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
342 if (err)
343 goto out;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700344 drop_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345
Dave Hansence71ec32006-09-30 23:29:06 -0700346 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 inode->i_ctime = CURRENT_TIME_SEC;
348 fat_detach(inode);
349out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700350 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700351 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700352 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353
354 return err;
355}
356
357/***** Make a directory */
358static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode)
359{
360 struct super_block *sb = dir->i_sb;
361 struct fat_slot_info sinfo;
362 struct inode *inode;
363 unsigned char msdos_name[MSDOS_NAME];
364 struct timespec ts;
365 int err, is_hid, cluster;
366
Linus Torvalds8f593422008-05-19 19:53:01 -0700367 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
369 err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
370 msdos_name, &MSDOS_SB(sb)->options);
371 if (err)
372 goto out;
373 is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
374 /* foo vs .foo situation */
375 if (!fat_scan(dir, msdos_name, &sinfo)) {
376 brelse(sinfo.bh);
377 err = -EINVAL;
378 goto out;
379 }
380
381 ts = CURRENT_TIME_SEC;
382 cluster = fat_alloc_new_dir(dir, &ts);
383 if (cluster < 0) {
384 err = cluster;
385 goto out;
386 }
387 err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &ts, &sinfo);
388 if (err)
389 goto out_free;
Dave Hansend8c76e62006-09-30 23:29:04 -0700390 inc_nlink(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391
392 inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
393 brelse(sinfo.bh);
394 if (IS_ERR(inode)) {
395 err = PTR_ERR(inode);
396 /* the directory was completed, just return a error */
397 goto out;
398 }
399 inode->i_nlink = 2;
400 inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
401 /* timestamp is already written, so mark_inode_dirty() is unneeded. */
402
403 d_instantiate(dentry, inode);
404
Linus Torvalds8f593422008-05-19 19:53:01 -0700405 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700406 fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 return 0;
408
409out_free:
410 fat_free_clusters(dir, cluster);
411out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700412 unlock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 return err;
414}
415
416/***** Unlink a file */
417static int msdos_unlink(struct inode *dir, struct dentry *dentry)
418{
419 struct inode *inode = dentry->d_inode;
Linus Torvalds8f593422008-05-19 19:53:01 -0700420 struct super_block *sb= inode->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421 struct fat_slot_info sinfo;
422 int err;
423
Linus Torvalds8f593422008-05-19 19:53:01 -0700424 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
426 if (err)
427 goto out;
428
429 err = fat_remove_entries(dir, &sinfo); /* and releases bh */
430 if (err)
431 goto out;
Dave Hansence71ec32006-09-30 23:29:06 -0700432 clear_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 inode->i_ctime = CURRENT_TIME_SEC;
434 fat_detach(inode);
435out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700436 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700437 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700438 err = fat_flush_inodes(sb, dir, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
440 return err;
441}
442
443static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
444 struct dentry *old_dentry,
445 struct inode *new_dir, unsigned char *new_name,
446 struct dentry *new_dentry, int is_hid)
447{
448 struct buffer_head *dotdot_bh;
449 struct msdos_dir_entry *dotdot_de;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 struct inode *old_inode, *new_inode;
451 struct fat_slot_info old_sinfo, sinfo;
452 struct timespec ts;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800453 loff_t dotdot_i_pos, new_i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 int err, old_attrs, is_dir, update_dotdot, corrupt = 0;
455
456 old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
457 old_inode = old_dentry->d_inode;
458 new_inode = new_dentry->d_inode;
459
460 err = fat_scan(old_dir, old_name, &old_sinfo);
461 if (err) {
462 err = -EIO;
463 goto out;
464 }
465
466 is_dir = S_ISDIR(old_inode->i_mode);
467 update_dotdot = (is_dir && old_dir != new_dir);
468 if (update_dotdot) {
469 if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de,
470 &dotdot_i_pos) < 0) {
471 err = -EIO;
472 goto out;
473 }
474 }
475
476 old_attrs = MSDOS_I(old_inode)->i_attrs;
477 err = fat_scan(new_dir, new_name, &sinfo);
478 if (!err) {
479 if (!new_inode) {
480 /* "foo" -> ".foo" case. just change the ATTR_HIDDEN */
481 if (sinfo.de != old_sinfo.de) {
482 err = -EINVAL;
483 goto out;
484 }
485 if (is_hid)
486 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
487 else
488 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
489 if (IS_DIRSYNC(old_dir)) {
490 err = fat_sync_inode(old_inode);
491 if (err) {
492 MSDOS_I(old_inode)->i_attrs = old_attrs;
493 goto out;
494 }
495 } else
496 mark_inode_dirty(old_inode);
497
498 old_dir->i_version++;
499 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
500 if (IS_DIRSYNC(old_dir))
501 (void)fat_sync_inode(old_dir);
502 else
503 mark_inode_dirty(old_dir);
504 goto out;
505 }
506 }
507
508 ts = CURRENT_TIME_SEC;
509 if (new_inode) {
510 if (err)
511 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 if (is_dir) {
513 err = fat_dir_empty(new_inode);
514 if (err)
515 goto out;
516 }
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800517 new_i_pos = MSDOS_I(new_inode)->i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 fat_detach(new_inode);
519 } else {
520 err = msdos_add_entry(new_dir, new_name, is_dir, is_hid, 0,
521 &ts, &sinfo);
522 if (err)
523 goto out;
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800524 new_i_pos = sinfo.i_pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525 }
526 new_dir->i_version++;
527
528 fat_detach(old_inode);
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800529 fat_attach(old_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 if (is_hid)
531 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
532 else
533 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
534 if (IS_DIRSYNC(new_dir)) {
535 err = fat_sync_inode(old_inode);
536 if (err)
537 goto error_inode;
538 } else
539 mark_inode_dirty(old_inode);
540
541 if (update_dotdot) {
542 int start = MSDOS_I(new_dir)->i_logstart;
543 dotdot_de->start = cpu_to_le16(start);
544 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -0400545 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 if (IS_DIRSYNC(new_dir)) {
547 err = sync_dirty_buffer(dotdot_bh);
548 if (err)
549 goto error_dotdot;
550 }
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700551 drop_nlink(old_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 if (!new_inode)
Dave Hansend8c76e62006-09-30 23:29:04 -0700553 inc_nlink(new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 }
555
556 err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */
557 old_sinfo.bh = NULL;
558 if (err)
559 goto error_dotdot;
560 old_dir->i_version++;
561 old_dir->i_ctime = old_dir->i_mtime = ts;
562 if (IS_DIRSYNC(old_dir))
563 (void)fat_sync_inode(old_dir);
564 else
565 mark_inode_dirty(old_dir);
566
567 if (new_inode) {
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700568 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569 if (is_dir)
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700570 drop_nlink(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 new_inode->i_ctime = ts;
572 }
573out:
574 brelse(sinfo.bh);
575 brelse(dotdot_bh);
576 brelse(old_sinfo.bh);
577 return err;
578
579error_dotdot:
580 /* data cluster is shared, serious corruption */
581 corrupt = 1;
582
583 if (update_dotdot) {
584 int start = MSDOS_I(old_dir)->i_logstart;
585 dotdot_de->start = cpu_to_le16(start);
586 dotdot_de->starthi = cpu_to_le16(start >> 16);
Al Virob5224122009-06-07 13:44:36 -0400587 mark_buffer_dirty_inode(dotdot_bh, old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 corrupt |= sync_dirty_buffer(dotdot_bh);
589 }
590error_inode:
591 fat_detach(old_inode);
592 fat_attach(old_inode, old_sinfo.i_pos);
593 MSDOS_I(old_inode)->i_attrs = old_attrs;
594 if (new_inode) {
OGAWA Hirofumi9131dd42005-10-30 15:03:50 -0800595 fat_attach(new_inode, new_i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 if (corrupt)
597 corrupt |= fat_sync_inode(new_inode);
598 } else {
599 /*
600 * If new entry was not sharing the data cluster, it
601 * shouldn't be serious corruption.
602 */
603 int err2 = fat_remove_entries(new_dir, &sinfo);
604 if (corrupt)
605 corrupt |= err2;
606 sinfo.bh = NULL;
607 }
608 if (corrupt < 0) {
Denis Karpov85c78592009-06-04 02:34:22 +0900609 fat_fs_error(new_dir->i_sb,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 "%s: Filesystem corrupted (i_pos %lld)",
Harvey Harrison8e24eea2008-04-30 00:55:09 -0700611 __func__, sinfo.i_pos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 }
613 goto out;
614}
615
616/***** Rename, a wrapper for rename_same_dir & rename_diff_dir */
617static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
618 struct inode *new_dir, struct dentry *new_dentry)
619{
Linus Torvalds8f593422008-05-19 19:53:01 -0700620 struct super_block *sb = old_dir->i_sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
622 int err, is_hid;
623
Linus Torvalds8f593422008-05-19 19:53:01 -0700624 lock_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625
626 err = msdos_format_name(old_dentry->d_name.name,
627 old_dentry->d_name.len, old_msdos_name,
628 &MSDOS_SB(old_dir->i_sb)->options);
629 if (err)
630 goto out;
631 err = msdos_format_name(new_dentry->d_name.name,
632 new_dentry->d_name.len, new_msdos_name,
633 &MSDOS_SB(new_dir->i_sb)->options);
634 if (err)
635 goto out;
636
637 is_hid =
638 (new_dentry->d_name.name[0] == '.') && (new_msdos_name[0] != '.');
639
640 err = do_msdos_rename(old_dir, old_msdos_name, old_dentry,
641 new_dir, new_msdos_name, new_dentry, is_hid);
642out:
Linus Torvalds8f593422008-05-19 19:53:01 -0700643 unlock_super(sb);
Chris Masonae78bf92006-09-29 02:00:03 -0700644 if (!err)
Linus Torvalds8f593422008-05-19 19:53:01 -0700645 err = fat_flush_inodes(sb, old_dir, new_dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 return err;
647}
648
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -0800649static const struct inode_operations msdos_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 .create = msdos_create,
651 .lookup = msdos_lookup,
652 .unlink = msdos_unlink,
653 .mkdir = msdos_mkdir,
654 .rmdir = msdos_rmdir,
655 .rename = msdos_rename,
OGAWA Hirofumi1278fdd2008-04-28 02:16:25 -0700656 .setattr = fat_setattr,
OGAWA Hirofumida63fc72006-11-16 01:19:28 -0800657 .getattr = fat_getattr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658};
659
Al Viro3d239852010-12-18 10:44:00 -0500660static void setup(struct super_block *sb)
661{
662 sb->s_d_op = &msdos_dentry_operations;
663 sb->s_flags |= MS_NOATIME;
664}
665
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666static int msdos_fill_super(struct super_block *sb, void *data, int silent)
667{
Al Viro3d239852010-12-18 10:44:00 -0500668 return fat_fill_super(sb, data, silent, &msdos_dir_inode_operations,
669 0, setup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670}
671
Al Viro152a0832010-07-25 00:46:55 +0400672static struct dentry *msdos_mount(struct file_system_type *fs_type,
David Howells454e2392006-06-23 02:02:57 -0700673 int flags, const char *dev_name,
Al Viro152a0832010-07-25 00:46:55 +0400674 void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675{
Al Viro152a0832010-07-25 00:46:55 +0400676 return mount_bdev(fs_type, flags, dev_name, data, msdos_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677}
678
679static struct file_system_type msdos_fs_type = {
680 .owner = THIS_MODULE,
681 .name = "msdos",
Al Viro152a0832010-07-25 00:46:55 +0400682 .mount = msdos_mount,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683 .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)