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         d_set_d_op(dentry, &msdos_dentry_operations);
 231         dentry = d_splice_alias(inode, dentry);
 232         if (dentry)
 233                 d_set_d_op(dentry, &msdos_dentry_operations);
 234         return dentry;
 235
 236 error:
 237         unlock_super(sb);
 238         return ERR_PTR(err);
 239 }
 240
 241 /***** Creates a directory entry (name is already formatted). */
 242 static int msdos_add_entry(struct inode *dir, const unsigned char *name,
 243                            int is_dir, int is_hid, int cluster,
 244                            struct timespec *ts, struct fat_slot_info *sinfo)
 245 {
 246         struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
 247         struct msdos_dir_entry de;
 248         __le16 time, date;
 249         int err;
 250
 251         memcpy(de.name, name, MSDOS_NAME);
 252         de.attr = is_dir ? ATTR_DIR : ATTR_ARCH;
 253         if (is_hid)
 254                 de.attr |= ATTR_HIDDEN;
 255         de.lcase = 0;
 256         fat_time_unix2fat(sbi, ts, &time, &date, NULL);
 257         de.cdate = de.adate = 0;
 258         de.ctime = 0;
 259         de.ctime_cs = 0;
 260         de.time = time;
 261         de.date = date;
 262         de.start = cpu_to_le16(cluster);
 263         de.starthi = cpu_to_le16(cluster >> 16);
 264         de.size = 0;
 265
 266         err = fat_add_entries(dir, &de, 1, sinfo);
 267         if (err)
 268                 return err;
 269
 270         dir->i_ctime = dir->i_mtime = *ts;
 271         if (IS_DIRSYNC(dir))
 272                 (void)fat_sync_inode(dir);
 273         else
 274                 mark_inode_dirty(dir);
 275
 276         return 0;
 277 }
 278
 279 /***** Create a file */
 280 static int msdos_create(struct inode *dir, struct dentry *dentry, int mode,
 281                         struct nameidata *nd)
 282 {
 283         struct super_block *sb = dir->i_sb;
 284         struct inode *inode = NULL;
 285         struct fat_slot_info sinfo;
 286         struct timespec ts;
 287         unsigned char msdos_name[MSDOS_NAME];
 288         int err, is_hid;
 289
 290         lock_super(sb);
 291
 292         err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
 293                                 msdos_name, &MSDOS_SB(sb)->options);
 294         if (err)
 295                 goto out;
 296         is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
 297         /* Have to do it due to foo vs. .foo conflicts */
 298         if (!fat_scan(dir, msdos_name, &sinfo)) {
 299                 brelse(sinfo.bh);
 300                 err = -EINVAL;
 301                 goto out;
 302         }
 303
 304         ts = CURRENT_TIME_SEC;
 305         err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &ts, &sinfo);
 306         if (err)
 307                 goto out;
 308         inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
 309         brelse(sinfo.bh);
 310         if (IS_ERR(inode)) {
 311                 err = PTR_ERR(inode);
 312                 goto out;
 313         }
 314         inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
 315         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 316
 317         d_instantiate(dentry, inode);
 318 out:
 319         unlock_super(sb);
 320         if (!err)
 321                 err = fat_flush_inodes(sb, dir, inode);
 322         return err;
 323 }
 324
 325 /***** Remove a directory */
 326 static int msdos_rmdir(struct inode *dir, struct dentry *dentry)
 327 {
 328         struct super_block *sb = dir->i_sb;
 329         struct inode *inode = dentry->d_inode;
 330         struct fat_slot_info sinfo;
 331         int err;
 332
 333         lock_super(sb);
 334         /*
 335          * Check whether the directory is not in use, then check
 336          * whether it is empty.
 337          */
 338         err = fat_dir_empty(inode);
 339         if (err)
 340                 goto out;
 341         err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
 342         if (err)
 343                 goto out;
 344
 345         err = fat_remove_entries(dir, &sinfo);  /* and releases bh */
 346         if (err)
 347                 goto out;
 348         drop_nlink(dir);
 349
 350         clear_nlink(inode);
 351         inode->i_ctime = CURRENT_TIME_SEC;
 352         fat_detach(inode);
 353 out:
 354         unlock_super(sb);
 355         if (!err)
 356                 err = fat_flush_inodes(sb, dir, inode);
 357
 358         return err;
 359 }
 360
 361 /***** Make a directory */
 362 static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 363 {
 364         struct super_block *sb = dir->i_sb;
 365         struct fat_slot_info sinfo;
 366         struct inode *inode;
 367         unsigned char msdos_name[MSDOS_NAME];
 368         struct timespec ts;
 369         int err, is_hid, cluster;
 370
 371         lock_super(sb);
 372
 373         err = msdos_format_name(dentry->d_name.name, dentry->d_name.len,
 374                                 msdos_name, &MSDOS_SB(sb)->options);
 375         if (err)
 376                 goto out;
 377         is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.');
 378         /* foo vs .foo situation */
 379         if (!fat_scan(dir, msdos_name, &sinfo)) {
 380                 brelse(sinfo.bh);
 381                 err = -EINVAL;
 382                 goto out;
 383         }
 384
 385         ts = CURRENT_TIME_SEC;
 386         cluster = fat_alloc_new_dir(dir, &ts);
 387         if (cluster < 0) {
 388                 err = cluster;
 389                 goto out;
 390         }
 391         err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &ts, &sinfo);
 392         if (err)
 393                 goto out_free;
 394         inc_nlink(dir);
 395
 396         inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
 397         brelse(sinfo.bh);
 398         if (IS_ERR(inode)) {
 399                 err = PTR_ERR(inode);
 400                 /* the directory was completed, just return a error */
 401                 goto out;
 402         }
 403         inode->i_nlink = 2;
 404         inode->i_mtime = inode->i_atime = inode->i_ctime = ts;
 405         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 406
 407         d_instantiate(dentry, inode);
 408
 409         unlock_super(sb);
 410         fat_flush_inodes(sb, dir, inode);
 411         return 0;
 412
 413 out_free:
 414         fat_free_clusters(dir, cluster);
 415 out:
 416         unlock_super(sb);
 417         return err;
 418 }
 419
 420 /***** Unlink a file */
 421 static int msdos_unlink(struct inode *dir, struct dentry *dentry)
 422 {
 423         struct inode *inode = dentry->d_inode;
 424         struct super_block *sb= inode->i_sb;
 425         struct fat_slot_info sinfo;
 426         int err;
 427
 428         lock_super(sb);
 429         err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo);
 430         if (err)
 431                 goto out;
 432
 433         err = fat_remove_entries(dir, &sinfo);  /* and releases bh */
 434         if (err)
 435                 goto out;
 436         clear_nlink(inode);
 437         inode->i_ctime = CURRENT_TIME_SEC;
 438         fat_detach(inode);
 439 out:
 440         unlock_super(sb);
 441         if (!err)
 442                 err = fat_flush_inodes(sb, dir, inode);
 443
 444         return err;
 445 }
 446
 447 static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
 448                            struct dentry *old_dentry,
 449                            struct inode *new_dir, unsigned char *new_name,
 450                            struct dentry *new_dentry, int is_hid)
 451 {
 452         struct buffer_head *dotdot_bh;
 453         struct msdos_dir_entry *dotdot_de;
 454         struct inode *old_inode, *new_inode;
 455         struct fat_slot_info old_sinfo, sinfo;
 456         struct timespec ts;
 457         loff_t dotdot_i_pos, new_i_pos;
 458         int err, old_attrs, is_dir, update_dotdot, corrupt = 0;
 459
 460         old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
 461         old_inode = old_dentry->d_inode;
 462         new_inode = new_dentry->d_inode;
 463
 464         err = fat_scan(old_dir, old_name, &old_sinfo);
 465         if (err) {
 466                 err = -EIO;
 467                 goto out;
 468         }
 469
 470         is_dir = S_ISDIR(old_inode->i_mode);
 471         update_dotdot = (is_dir && old_dir != new_dir);
 472         if (update_dotdot) {
 473                 if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de,
 474                                          &dotdot_i_pos) < 0) {
 475                         err = -EIO;
 476                         goto out;
 477                 }
 478         }
 479
 480         old_attrs = MSDOS_I(old_inode)->i_attrs;
 481         err = fat_scan(new_dir, new_name, &sinfo);
 482         if (!err) {
 483                 if (!new_inode) {
 484                         /* "foo" -> ".foo" case. just change the ATTR_HIDDEN */
 485                         if (sinfo.de != old_sinfo.de) {
 486                                 err = -EINVAL;
 487                                 goto out;
 488                         }
 489                         if (is_hid)
 490                                 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
 491                         else
 492                                 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
 493                         if (IS_DIRSYNC(old_dir)) {
 494                                 err = fat_sync_inode(old_inode);
 495                                 if (err) {
 496                                         MSDOS_I(old_inode)->i_attrs = old_attrs;
 497                                         goto out;
 498                                 }
 499                         } else
 500                                 mark_inode_dirty(old_inode);
 501
 502                         old_dir->i_version++;
 503                         old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
 504                         if (IS_DIRSYNC(old_dir))
 505                                 (void)fat_sync_inode(old_dir);
 506                         else
 507                                 mark_inode_dirty(old_dir);
 508                         goto out;
 509                 }
 510         }
 511
 512         ts = CURRENT_TIME_SEC;
 513         if (new_inode) {
 514                 if (err)
 515                         goto out;
 516                 if (is_dir) {
 517                         err = fat_dir_empty(new_inode);
 518                         if (err)
 519                                 goto out;
 520                 }
 521                 new_i_pos = MSDOS_I(new_inode)->i_pos;
 522                 fat_detach(new_inode);
 523         } else {
 524                 err = msdos_add_entry(new_dir, new_name, is_dir, is_hid, 0,
 525                                       &ts, &sinfo);
 526                 if (err)
 527                         goto out;
 528                 new_i_pos = sinfo.i_pos;
 529         }
 530         new_dir->i_version++;
 531
 532         fat_detach(old_inode);
 533         fat_attach(old_inode, new_i_pos);
 534         if (is_hid)
 535                 MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN;
 536         else
 537                 MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN;
 538         if (IS_DIRSYNC(new_dir)) {
 539                 err = fat_sync_inode(old_inode);
 540                 if (err)
 541                         goto error_inode;
 542         } else
 543                 mark_inode_dirty(old_inode);
 544
 545         if (update_dotdot) {
 546                 int start = MSDOS_I(new_dir)->i_logstart;
 547                 dotdot_de->start = cpu_to_le16(start);
 548                 dotdot_de->starthi = cpu_to_le16(start >> 16);
 549                 mark_buffer_dirty_inode(dotdot_bh, old_inode);
 550                 if (IS_DIRSYNC(new_dir)) {
 551                         err = sync_dirty_buffer(dotdot_bh);
 552                         if (err)
 553                                 goto error_dotdot;
 554                 }
 555                 drop_nlink(old_dir);
 556                 if (!new_inode)
 557                         inc_nlink(new_dir);
 558         }
 559
 560         err = fat_remove_entries(old_dir, &old_sinfo);  /* and releases bh */
 561         old_sinfo.bh = NULL;
 562         if (err)
 563                 goto error_dotdot;
 564         old_dir->i_version++;
 565         old_dir->i_ctime = old_dir->i_mtime = ts;
 566         if (IS_DIRSYNC(old_dir))
 567                 (void)fat_sync_inode(old_dir);
 568         else
 569                 mark_inode_dirty(old_dir);
 570
 571         if (new_inode) {
 572                 drop_nlink(new_inode);
 573                 if (is_dir)
 574                         drop_nlink(new_inode);
 575                 new_inode->i_ctime = ts;
 576         }
 577 out:
 578         brelse(sinfo.bh);
 579         brelse(dotdot_bh);
 580         brelse(old_sinfo.bh);
 581         return err;
 582
 583 error_dotdot:
 584         /* data cluster is shared, serious corruption */
 585         corrupt = 1;
 586
 587         if (update_dotdot) {
 588                 int start = MSDOS_I(old_dir)->i_logstart;
 589                 dotdot_de->start = cpu_to_le16(start);
 590                 dotdot_de->starthi = cpu_to_le16(start >> 16);
 591                 mark_buffer_dirty_inode(dotdot_bh, old_inode);
 592                 corrupt |= sync_dirty_buffer(dotdot_bh);
 593         }
 594 error_inode:
 595         fat_detach(old_inode);
 596         fat_attach(old_inode, old_sinfo.i_pos);
 597         MSDOS_I(old_inode)->i_attrs = old_attrs;
 598         if (new_inode) {
 599                 fat_attach(new_inode, new_i_pos);
 600                 if (corrupt)
 601                         corrupt |= fat_sync_inode(new_inode);
 602         } else {
 603                 /*
 604                  * If new entry was not sharing the data cluster, it
 605                  * shouldn't be serious corruption.
 606                  */
 607                 int err2 = fat_remove_entries(new_dir, &sinfo);
 608                 if (corrupt)
 609                         corrupt |= err2;
 610                 sinfo.bh = NULL;
 611         }
 612         if (corrupt < 0) {
 613                 fat_fs_error(new_dir->i_sb,
 614                              "%s: Filesystem corrupted (i_pos %lld)",
 615                              __func__, sinfo.i_pos);
 616         }
 617         goto out;
 618 }
 619
 620 /***** Rename, a wrapper for rename_same_dir & rename_diff_dir */
 621 static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry,
 622                         struct inode *new_dir, struct dentry *new_dentry)
 623 {
 624         struct super_block *sb = old_dir->i_sb;
 625         unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME];
 626         int err, is_hid;
 627
 628         lock_super(sb);
 629
 630         err = msdos_format_name(old_dentry->d_name.name,
 631                                 old_dentry->d_name.len, old_msdos_name,
 632                                 &MSDOS_SB(old_dir->i_sb)->options);
 633         if (err)
 634                 goto out;
 635         err = msdos_format_name(new_dentry->d_name.name,
 636                                 new_dentry->d_name.len, new_msdos_name,
 637                                 &MSDOS_SB(new_dir->i_sb)->options);
 638         if (err)
 639                 goto out;
 640
 641         is_hid =
 642              (new_dentry->d_name.name[0] == '.') && (new_msdos_name[0] != '.');
 643
 644         err = do_msdos_rename(old_dir, old_msdos_name, old_dentry,
 645                               new_dir, new_msdos_name, new_dentry, is_hid);
 646 out:
 647         unlock_super(sb);
 648         if (!err)
 649                 err = fat_flush_inodes(sb, old_dir, new_dir);
 650         return err;
 651 }
 652
 653 static const struct inode_operations msdos_dir_inode_operations = {
 654         .create         = msdos_create,
 655         .lookup         = msdos_lookup,
 656         .unlink         = msdos_unlink,
 657         .mkdir          = msdos_mkdir,
 658         .rmdir          = msdos_rmdir,
 659         .rename         = msdos_rename,
 660         .setattr        = fat_setattr,
 661         .getattr        = fat_getattr,
 662 };
 663
 664 static int msdos_fill_super(struct super_block *sb, void *data, int silent)
 665 {
 666         int res;
 667
 668         lock_super(sb);
 669         res = fat_fill_super(sb, data, silent, &msdos_dir_inode_operations, 0);
 670         if (res) {
 671                 unlock_super(sb);
 672                 return res;
 673         }
 674
 675         sb->s_flags |= MS_NOATIME;
 676         d_set_d_op(sb->s_root, &msdos_dentry_operations);
 677         unlock_super(sb);
 678         return 0;
 679 }
 680
 681 static struct dentry *msdos_mount(struct file_system_type *fs_type,
 682                         int flags, const char *dev_name,
 683                         void *data)
 684 {
 685         return mount_bdev(fs_type, flags, dev_name, data, msdos_fill_super);
 686 }
 687
 688 static struct file_system_type msdos_fs_type = {
 689         .owner          = THIS_MODULE,
 690         .name           = "msdos",
 691         .mount          = msdos_mount,
 692         .kill_sb        = kill_block_super,
 693         .fs_flags       = FS_REQUIRES_DEV,
 694 };
 695
 696 static int __init init_msdos_fs(void)
 697 {
 698         return register_filesystem(&msdos_fs_type);
 699 }
 700
 701 static void __exit exit_msdos_fs(void)
 702 {
 703         unregister_filesystem(&msdos_fs_type);
 704 }
 705
 706 MODULE_LICENSE("GPL");
 707 MODULE_AUTHOR("Werner Almesberger");
 708 MODULE_DESCRIPTION("MS-DOS filesystem support");
 709
 710 module_init(init_msdos_fs)
 711 module_exit(exit_msdos_fs)