fs/fat/namei_msdos.c

   1 /*
   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 "fat.h"
  13
  14 /* Characters that are undesirable in an MS-DOS file name */
  15 static unsigned char bad_chars[] = "*?<>|\"";
  16 static unsigned char bad_if_strict[] = "+=,; ";
  17
  18 /***** Formats an MS-DOS file name. Rejects invalid names. */
  19 static 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;
  29         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--;
  37                 } else
  38                         return -EINVAL;
  39         }
  40         /*
  41          * disallow names that _really_ start with a dot
  42          */
  43         space = 1;
  44         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;
  50                 if (opts->name_check == 's' && strchr(bad_if_strict, c))
  51                         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' &&
  90                             strchr(bad_if_strict, c))
  91                                 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++ = ' ';
 114
 115         return 0;
 116 }
 117
 118 /***** Locates a directory entry.  Uses unformatted name. */
 119 static 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  */
 151 static int msdos_hash(const struct dentry *dentry, const struct inode *inode,
 152                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  */
 168 static 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)
 171 {
 172         struct fat_mount_options *options = &MSDOS_SB(parent->d_sb)->options;
 173         unsigned char a_msdos_name[MSDOS_NAME], b_msdos_name[MSDOS_NAME];
 174         int error;
 175
 176         error = msdos_format_name(name->name, name->len, a_msdos_name, options);
 177         if (error)
 178                 goto old_compare;
 179         error = msdos_format_name(str, len, b_msdos_name, options);
 180         if (error)
 181                 goto old_compare;
 182         error = memcmp(a_msdos_name, b_msdos_name, MSDOS_NAME);
 183 out:
 184         return error;
 185
 186 old_compare:
 187         error = 1;
 188         if (name->len == len)
 189                 error = memcmp(name->name, str, len);
 190         goto out;
 191 }
 192
 193 static const struct dentry_operations msdos_dentry_operations = {
 194         .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 */
 203 static 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;
 208         struct inode *inode;
 209         int err;
 210
 211         lock_super(sb);
 212
 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
 222         inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
 223         brelse(sinfo.bh);
 224         if (IS_ERR(inode)) {
 225                 err = PTR_ERR(inode);
 226                 goto error;
 227         }
 228 out:
 229         unlock_super(sb);
 230         return d_splice_alias(inode, dentry);
 231
 232 error:
 233         unlock_super(sb);
 234         return ERR_PTR(err);
 235 }
 236
 237 /***** Creates a directory entry (name is already formatted). */
 238 static 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 {
 242         struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
 243         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;
 252         fat_time_unix2fat(sbi, ts, &time, &date, NULL);
 253         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 */
 276 static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
 277                         struct nameidata *nd)
 278 {
 279         struct super_block *sb = dir->i_sb;
 280         struct inode *inode = NULL;
 281         struct fat_slot_info sinfo;
 282         struct timespec ts;
 283         unsigned char msdos_name[MSDOS_NAME];
 284         int err, is_hid;
 285
 286         lock_super(sb);
 287
 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);
 314 out:
 315         unlock_super(sb);
 316         if (!err)
 317                 err = fat_flush_inodes(sb, dir, inode);
 318         return err;
 319 }
 320
 321 /***** Remove a directory */
 322 static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
 323 {
 324         struct super_block *sb = dir->i_sb;
 325         struct inode *inode = dentry->d_inode;
 326         struct fat_slot_info sinfo;
 327         int err;
 328
 329         lock_super(sb);
 330         /*
 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;
 344         drop_nlink(dir);
 345
 346         clear_nlink(inode);
 347         inode->i_ctime = CURRENT_TIME_SEC;
 348         fat_detach(inode);
 349 out:
 350         unlock_super(sb);
 351         if (!err)
 352                 err = fat_flush_inodes(sb, dir, inode);
 353
 354         return err;
 355 }
 356
 357 /***** Make a directory */
 358 static 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
 367         lock_super(sb);
 368
 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;
 390         inc_nlink(dir);
 391
 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
 405         unlock_super(sb);
 406         fat_flush_inodes(sb, dir, inode);
 407         return 0;
 408
 409 out_free:
 410         fat_free_clusters(dir, cluster);
 411 out:
 412         unlock_super(sb);
 413         return err;
 414 }
 415
 416 /***** Unlink a file */
 417 static int msdos_unlink(struct inode *dir, struct dentry *dentry)
 418 {
 419         struct inode *inode = dentry->d_inode;
 420         struct super_block *sb= inode->i_sb;
 421         struct fat_slot_info sinfo;
 422         int err;
 423
 424         lock_super(sb);
 425         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;
 432         clear_nlink(inode);
 433         inode->i_ctime = CURRENT_TIME_SEC;
 434         fat_detach(inode);
 435 out:
 436         unlock_super(sb);
 437         if (!err)
 438                 err = fat_flush_inodes(sb, dir, inode);
 439
 440         return err;
 441 }
 442
 443 static 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;
 450         struct inode *old_inode, *new_inode;
 451         struct fat_slot_info old_sinfo, sinfo;
 452         struct timespec ts;
 453         loff_t dotdot_i_pos, new_i_pos;
 454         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;
 512                 if (is_dir) {
 513                         err = fat_dir_empty(new_inode);
 514                         if (err)
 515                                 goto out;
 516                 }
 517                 new_i_pos = MSDOS_I(new_inode)->i_pos;
 518                 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;
 524                 new_i_pos = sinfo.i_pos;
 525         }
 526         new_dir->i_version++;
 527
 528         fat_detach(old_inode);
 529         fat_attach(old_inode, new_i_pos);
 530         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);
 545                 mark_buffer_dirty_inode(dotdot_bh, old_inode);
 546                 if (IS_DIRSYNC(new_dir)) {
 547                         err = sync_dirty_buffer(dotdot_bh);
 548                         if (err)
 549                                 goto error_dotdot;
 550                 }
 551                 drop_nlink(old_dir);
 552                 if (!new_inode)
 553                         inc_nlink(new_dir);
 554         }
 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) {
 568                 drop_nlink(new_inode);
 569                 if (is_dir)
 570                         drop_nlink(new_inode);
 571                 new_inode->i_ctime = ts;
 572         }
 573 out:
 574         brelse(sinfo.bh);
 575         brelse(dotdot_bh);
 576         brelse(old_sinfo.bh);
 577         return err;
 578
 579 error_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);
 587                 mark_buffer_dirty_inode(dotdot_bh, old_inode);
 588                 corrupt |= sync_dirty_buffer(dotdot_bh);
 589         }
 590 error_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) {
 595                 fat_attach(new_inode, new_i_pos);
 596                 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) {
 609                 fat_fs_error(new_dir->i_sb,
 610                              "%s: Filesystem corrupted (i_pos %lld)",
 611                              __func__, sinfo.i_pos);
 612         }
 613         goto out;
 614 }
 615
 616 /***** Rename, a wrapper for rename_same_dir & rename_diff_dir */
 617 static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
 618                         struct inode *new_dir, struct dentry *new_dentry)
 619 {
 620         struct super_block *sb = old_dir->i_sb;
 621         unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
 622         int err, is_hid;
 623
 624         lock_super(sb);
 625
 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);
 642 out:
 643         unlock_super(sb);
 644         if (!err)
 645                 err = fat_flush_inodes(sb, old_dir, new_dir);
 646         return err;
 647 }
 648
 649 static const struct inode_operations msdos_dir_inode_operations = {
 650         .create         = msdos_create,
 651         .lookup         = msdos_lookup,
 652         .unlink         = msdos_unlink,
 653         .mkdir          = msdos_mkdir,
 654         .rmdir          = msdos_rmdir,
 655         .rename         = msdos_rename,
 656         .setattr        = fat_setattr,
 657         .getattr        = fat_getattr,
 658 };
 659
 660 static void setup(struct super_block *sb)
 661 {
 662         sb->s_d_op = &msdos_dentry_operations;
 663         sb->s_flags |= MS_NOATIME;
 664 }
 665
 666 static int msdos_fill_super(struct super_block *sb, void *data, int silent)
 667 {
 668         return fat_fill_super(sb, data, silent, &msdos_dir_inode_operations,
 669                              0, setup);
 670 }
 671
 672 static struct dentry *msdos_mount(struct file_system_type *fs_type,
 673                         int flags, const char *dev_name,
 674                         void *data)
 675 {
 676         return mount_bdev(fs_type, flags, dev_name, data, msdos_fill_super);
 677 }
 678
 679 static struct file_system_type msdos_fs_type = {
 680         .owner          = THIS_MODULE,
 681         .name           = "msdos",
 682         .mount          = msdos_mount,
 683         .kill_sb        = kill_block_super,
 684         .fs_flags       = FS_REQUIRES_DEV,
 685 };
 686
 687 static int __init init_msdos_fs(void)
 688 {
 689         return register_filesystem(&msdos_fs_type);
 690 }
 691
 692 static void __exit exit_msdos_fs(void)
 693 {
 694         unregister_filesystem(&msdos_fs_type);
 695 }
 696
 697 MODULE_LICENSE("GPL");
 698 MODULE_AUTHOR("Werner Almesberger");
 699 MODULE_DESCRIPTION("MS-DOS filesystem support");
 700
 701 module_init(init_msdos_fs)
 702 module_exit(exit_msdos_fs)