fs/fat/dir.c

   1 /*
   2  *  linux/fs/fat/dir.c
   3  *
   4  *  directory handling functions for fat-based filesystems
   5  *
   6  *  Written 1992,1993 by Werner Almesberger
   7  *
   8  *  Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu>
   9  *
  10  *  VFAT extensions by Gordon Chaffee <chaffee@plateau.cs.berkeley.edu>
  11  *  Merged with msdos fs by Henrik Storner <storner@osiris.ping.dk>
  12  *  Rewritten for constant inumbers. Plugged buffer overrun in readdir(). AV
  13  *  Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de>
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/time.h>
  19 #include <linux/msdos_fs.h>
  20 #include <linux/smp_lock.h>
  21 #include <linux/buffer_head.h>
  22 #include <linux/compat.h>
  23 #include <asm/uaccess.h>
  24
  25 static inline loff_t fat_make_i_pos(struct super_block *sb,
  26                                     struct buffer_head *bh,
  27                                     struct msdos_dir_entry *de)
  28 {
  29         return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits)
  30                 | (de - (struct msdos_dir_entry *)bh->b_data);
  31 }
  32
  33 static inline void fat_dir_readahead(struct inode *dir, sector_t iblock,
  34                                      sector_t phys)
  35 {
  36         struct super_block *sb = dir->i_sb;
  37         struct msdos_sb_info *sbi = MSDOS_SB(sb);
  38         struct buffer_head *bh;
  39         int sec;
  40
  41         /* This is not a first sector of cluster, or sec_per_clus == 1 */
  42         if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1)
  43                 return;
  44         /* root dir of FAT12/FAT16 */
  45         if ((sbi->fat_bits != 32) && (dir->i_ino == MSDOS_ROOT_INO))
  46                 return;
  47
  48         bh = sb_find_get_block(sb, phys);
  49         if (bh == NULL || !buffer_uptodate(bh)) {
  50                 for (sec = 0; sec < sbi->sec_per_clus; sec++)
  51                         sb_breadahead(sb, phys + sec);
  52         }
  53         brelse(bh);
  54 }
  55
  56 /* Returns the inode number of the directory entry at offset pos. If bh is
  57    non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
  58    returned in bh.
  59    AV. Most often we do it item-by-item. Makes sense to optimize.
  60    AV. OK, there we go: if both bh and de are non-NULL we assume that we just
  61    AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
  62    AV. It's done in fat_get_entry() (inlined), here the slow case lives.
  63    AV. Additionally, when we return -1 (i.e. reached the end of directory)
  64    AV. we make bh NULL.
  65  */
  66 static int fat__get_entry(struct inode *dir, loff_t *pos,
  67                           struct buffer_head **bh, struct msdos_dir_entry **de)
  68 {
  69         struct super_block *sb = dir->i_sb;
  70         sector_t phys, iblock;
  71         unsigned long mapped_blocks;
  72         int err, offset;
  73
  74 next:
  75         if (*bh)
  76                 brelse(*bh);
  77
  78         *bh = NULL;
  79         iblock = *pos >> sb->s_blocksize_bits;
  80         err = fat_bmap(dir, iblock, &phys, &mapped_blocks);
  81         if (err || !phys)
  82                 return -1;      /* beyond EOF or error */
  83
  84         fat_dir_readahead(dir, iblock, phys);
  85
  86         *bh = sb_bread(sb, phys);
  87         if (*bh == NULL) {
  88                 printk(KERN_ERR "FAT: Directory bread(block %llu) failed\n",
  89                        (unsigned long long)phys);
  90                 /* skip this block */
  91                 *pos = (iblock + 1) << sb->s_blocksize_bits;
  92                 goto next;
  93         }
  94
  95         offset = *pos & (sb->s_blocksize - 1);
  96         *pos += sizeof(struct msdos_dir_entry);
  97         *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
  98
  99         return 0;
 100 }
 101
 102 static inline int fat_get_entry(struct inode *dir, loff_t *pos,
 103                                 struct buffer_head **bh,
 104                                 struct msdos_dir_entry **de)
 105 {
 106         /* Fast stuff first */
 107         if (*bh && *de &&
 108             (*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
 109                 *pos += sizeof(struct msdos_dir_entry);
 110                 (*de)++;
 111                 return 0;
 112         }
 113         return fat__get_entry(dir, pos, bh, de);
 114 }
 115
 116 /*
 117  * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII.
 118  * If uni_xlate is enabled and we can't get a 1:1 conversion, use a
 119  * colon as an escape character since it is normally invalid on the vfat
 120  * filesystem. The following four characters are the hexadecimal digits
 121  * of Unicode value. This lets us do a full dump and restore of Unicode
 122  * filenames. We could get into some trouble with long Unicode names,
 123  * but ignore that right now.
 124  * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
 125  */
 126 static int uni16_to_x8(unsigned char *ascii, const wchar_t *uni, int len,
 127                        int uni_xlate, struct nls_table *nls)
 128 {
 129         const wchar_t *ip;
 130         wchar_t ec;
 131         unsigned char *op, nc;
 132         int charlen;
 133         int k;
 134
 135         ip = uni;
 136         op = ascii;
 137
 138         while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) {
 139                 ec = *ip++;
 140                 if ( (charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE)) > 0) {
 141                         op += charlen;
 142                         len -= charlen;
 143                 } else {
 144                         if (uni_xlate == 1) {
 145                                 *op = ':';
 146                                 for (k = 4; k > 0; k--) {
 147                                         nc = ec & 0xF;
 148                                         op[k] = nc > 9  ? nc + ('a' - 10)
 149                                                         : nc + '0';
 150                                         ec >>= 4;
 151                                 }
 152                                 op += 5;
 153                                 len -= 5;
 154                         } else {
 155                                 *op++ = '?';
 156                                 len--;
 157                         }
 158                 }
 159         }
 160
 161         if (unlikely(*ip)) {
 162                 printk(KERN_WARNING "FAT: filename was truncated while "
 163                        "converting.");
 164         }
 165
 166         *op = 0;
 167         return (op - ascii);
 168 }
 169
 170 static inline int fat_uni_to_x8(struct msdos_sb_info *sbi, const wchar_t *uni,
 171                                 unsigned char *buf, int size)
 172 {
 173         if (sbi->options.utf8)
 174                 return utf8_wcstombs(buf, uni, size);
 175         else
 176                 return uni16_to_x8(buf, uni, size, sbi->options.unicode_xlate,
 177                                    sbi->nls_io);
 178 }
 179
 180 static inline int
 181 fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
 182 {
 183         int charlen;
 184
 185         charlen = t->char2uni(c, clen, uni);
 186         if (charlen < 0) {
 187                 *uni = 0x003f;  /* a question mark */
 188                 charlen = 1;
 189         }
 190         return charlen;
 191 }
 192
 193 static inline int
 194 fat_short2lower_uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
 195 {
 196         int charlen;
 197         wchar_t wc;
 198
 199         charlen = t->char2uni(c, clen, &wc);
 200         if (charlen < 0) {
 201                 *uni = 0x003f;  /* a question mark */
 202                 charlen = 1;
 203         } else if (charlen <= 1) {
 204                 unsigned char nc = t->charset2lower[*c];
 205
 206                 if (!nc)
 207                         nc = *c;
 208
 209                 if ( (charlen = t->char2uni(&nc, 1, uni)) < 0) {
 210                         *uni = 0x003f;  /* a question mark */
 211                         charlen = 1;
 212                 }
 213         } else
 214                 *uni = wc;
 215
 216         return charlen;
 217 }
 218
 219 static inline int
 220 fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size,
 221                   wchar_t *uni_buf, unsigned short opt, int lower)
 222 {
 223         int len = 0;
 224
 225         if (opt & VFAT_SFN_DISPLAY_LOWER)
 226                 len =  fat_short2lower_uni(nls, buf, buf_size, uni_buf);
 227         else if (opt & VFAT_SFN_DISPLAY_WIN95)
 228                 len = fat_short2uni(nls, buf, buf_size, uni_buf);
 229         else if (opt & VFAT_SFN_DISPLAY_WINNT) {
 230                 if (lower)
 231                         len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
 232                 else
 233                         len = fat_short2uni(nls, buf, buf_size, uni_buf);
 234         } else
 235                 len = fat_short2uni(nls, buf, buf_size, uni_buf);
 236
 237         return len;
 238 }
 239
 240 static inline int fat_name_match(struct msdos_sb_info *sbi,
 241                                  const unsigned char *a, int a_len,
 242                                  const unsigned char *b, int b_len)
 243 {
 244         if (a_len != b_len)
 245                 return 0;
 246
 247         if (sbi->options.name_check != 's')
 248                 return !nls_strnicmp(sbi->nls_io, a, b, a_len);
 249         else
 250                 return !memcmp(a, b, a_len);
 251 }
 252
 253 enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, };
 254
 255 /**
 256  * fat_parse_long - Parse extended directory entry.
 257  *
 258  * This function returns zero on success, negative value on error, or one of
 259  * the following:
 260  *
 261  * %PARSE_INVALID - Directory entry is invalid.
 262  * %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
 263  * %PARSE_EOF - Directory has no more entries.
 264  */
 265 static int fat_parse_long(struct inode *dir, loff_t *pos,
 266                           struct buffer_head **bh, struct msdos_dir_entry **de,
 267                           wchar_t **unicode, unsigned char *nr_slots)
 268 {
 269         struct msdos_dir_slot *ds;
 270         unsigned char id, slot, slots, alias_checksum;
 271
 272         if (!*unicode) {
 273                 *unicode = __getname();
 274                 if (!*unicode) {
 275                         brelse(*bh);
 276                         return -ENOMEM;
 277                 }
 278         }
 279 parse_long:
 280         slots = 0;
 281         ds = (struct msdos_dir_slot *)*de;
 282         id = ds->id;
 283         if (!(id & 0x40))
 284                 return PARSE_INVALID;
 285         slots = id & ~0x40;
 286         if (slots > 20 || !slots)       /* ceil(256 * 2 / 26) */
 287                 return PARSE_INVALID;
 288         *nr_slots = slots;
 289         alias_checksum = ds->alias_checksum;
 290
 291         slot = slots;
 292         while (1) {
 293                 int offset;
 294
 295                 slot--;
 296                 offset = slot * 13;
 297                 fat16_towchar(*unicode + offset, ds->name0_4, 5);
 298                 fat16_towchar(*unicode + offset + 5, ds->name5_10, 6);
 299                 fat16_towchar(*unicode + offset + 11, ds->name11_12, 2);
 300
 301                 if (ds->id & 0x40)
 302                         (*unicode)[offset + 13] = 0;
 303                 if (fat_get_entry(dir, pos, bh, de) < 0)
 304                         return PARSE_EOF;
 305                 if (slot == 0)
 306                         break;
 307                 ds = (struct msdos_dir_slot *)*de;
 308                 if (ds->attr != ATTR_EXT)
 309                         return PARSE_NOT_LONGNAME;
 310                 if ((ds->id & ~0x40) != slot)
 311                         goto parse_long;
 312                 if (ds->alias_checksum != alias_checksum)
 313                         goto parse_long;
 314         }
 315         if ((*de)->name[0] == DELETED_FLAG)
 316                 return PARSE_INVALID;
 317         if ((*de)->attr == ATTR_EXT)
 318                 goto parse_long;
 319         if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME))
 320                 return PARSE_INVALID;
 321         if (fat_checksum((*de)->name) != alias_checksum)
 322                 *nr_slots = 0;
 323
 324         return 0;
 325 }
 326
 327 /*
 328  * Maximum buffer size of short name.
 329  * [(MSDOS_NAME + '.') * max one char + nul]
 330  * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
 331  */
 332 #define FAT_MAX_SHORT_SIZE      ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
 333 /*
 334  * Maximum buffer size of unicode chars from slots.
 335  * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
 336  */
 337 #define FAT_MAX_UNI_CHARS       ((MSDOS_SLOTS - 1) * 13 + 1)
 338 #define FAT_MAX_UNI_SIZE        (FAT_MAX_UNI_CHARS * sizeof(wchar_t))
 339
 340 /*
 341  * Return values: negative -> error, 0 -> not found, positive -> found,
 342  * value is the total amount of slots, including the shortname entry.
 343  */
 344 int fat_search_long(struct inode *inode, const unsigned char *name,
 345                     int name_len, struct fat_slot_info *sinfo)
 346 {
 347         struct super_block *sb = inode->i_sb;
 348         struct msdos_sb_info *sbi = MSDOS_SB(sb);
 349         struct buffer_head *bh = NULL;
 350         struct msdos_dir_entry *de;
 351         struct nls_table *nls_disk = sbi->nls_disk;
 352         unsigned char nr_slots;
 353         wchar_t bufuname[14];
 354         wchar_t *unicode = NULL;
 355         unsigned char work[MSDOS_NAME];
 356         unsigned char bufname[FAT_MAX_SHORT_SIZE];
 357         unsigned short opt_shortname = sbi->options.shortname;
 358         loff_t cpos = 0;
 359         int chl, i, j, last_u, err, len;
 360
 361         err = -ENOENT;
 362         while (1) {
 363                 if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
 364                         goto end_of_dir;
 365 parse_record:
 366                 nr_slots = 0;
 367                 if (de->name[0] == DELETED_FLAG)
 368                         continue;
 369                 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
 370                         continue;
 371                 if (de->attr != ATTR_EXT && IS_FREE(de->name))
 372                         continue;
 373                 if (de->attr == ATTR_EXT) {
 374                         int status = fat_parse_long(inode, &cpos, &bh, &de,
 375                                                     &unicode, &nr_slots);
 376                         if (status < 0)
 377                                 return status;
 378                         else if (status == PARSE_INVALID)
 379                                 continue;
 380                         else if (status == PARSE_NOT_LONGNAME)
 381                                 goto parse_record;
 382                         else if (status == PARSE_EOF)
 383                                 goto end_of_dir;
 384                 }
 385
 386                 memcpy(work, de->name, sizeof(de->name));
 387                 /* see namei.c, msdos_format_name */
 388                 if (work[0] == 0x05)
 389                         work[0] = 0xE5;
 390                 for (i = 0, j = 0, last_u = 0; i < 8;) {
 391                         if (!work[i])
 392                                 break;
 393                         chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
 394                                                 &bufuname[j++], opt_shortname,
 395                                                 de->lcase & CASE_LOWER_BASE);
 396                         if (chl <= 1) {
 397                                 if (work[i] != ' ')
 398                                         last_u = j;
 399                         } else {
 400                                 last_u = j;
 401                         }
 402                         i += chl;
 403                 }
 404                 j = last_u;
 405                 fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
 406                 for (i = 8; i < MSDOS_NAME;) {
 407                         if (!work[i])
 408                                 break;
 409                         chl = fat_shortname2uni(nls_disk, &work[i],
 410                                                 MSDOS_NAME - i,
 411                                                 &bufuname[j++], opt_shortname,
 412                                                 de->lcase & CASE_LOWER_EXT);
 413                         if (chl <= 1) {
 414                                 if (work[i] != ' ')
 415                                         last_u = j;
 416                         } else {
 417                                 last_u = j;
 418                         }
 419                         i += chl;
 420                 }
 421                 if (!last_u)
 422                         continue;
 423
 424                 /* Compare shortname */
 425                 bufuname[last_u] = 0x0000;
 426                 len = fat_uni_to_x8(sbi, bufuname, bufname, sizeof(bufname));
 427                 if (fat_name_match(sbi, name, name_len, bufname, len))
 428                         goto found;
 429
 430                 if (nr_slots) {
 431                         void *longname = unicode + FAT_MAX_UNI_CHARS;
 432                         int size = PATH_MAX - FAT_MAX_UNI_SIZE;
 433
 434                         /* Compare longname */
 435                         len = fat_uni_to_x8(sbi, unicode, longname, size);
 436                         if (fat_name_match(sbi, name, name_len, longname, len))
 437                                 goto found;
 438                 }
 439         }
 440
 441 found:
 442         nr_slots++;     /* include the de */
 443         sinfo->slot_off = cpos - nr_slots * sizeof(*de);
 444         sinfo->nr_slots = nr_slots;
 445         sinfo->de = de;
 446         sinfo->bh = bh;
 447         sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
 448         err = 0;
 449 end_of_dir:
 450         if (unicode)
 451                 __putname(unicode);
 452
 453         return err;
 454 }
 455
 456 EXPORT_SYMBOL_GPL(fat_search_long);
 457
 458 struct fat_ioctl_filldir_callback {
 459         void __user *dirent;
 460         int result;
 461         /* for dir ioctl */
 462         const char *longname;
 463         int long_len;
 464         const char *shortname;
 465         int short_len;
 466 };
 467
 468 static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
 469                          filldir_t filldir, int short_only, int both)
 470 {
 471         struct super_block *sb = inode->i_sb;
 472         struct msdos_sb_info *sbi = MSDOS_SB(sb);
 473         struct buffer_head *bh;
 474         struct msdos_dir_entry *de;
 475         struct nls_table *nls_disk = sbi->nls_disk;
 476         unsigned char nr_slots;
 477         wchar_t bufuname[14];
 478         wchar_t *unicode = NULL;
 479         unsigned char c, work[MSDOS_NAME];
 480         unsigned char bufname[FAT_MAX_SHORT_SIZE], *ptname = bufname;
 481         unsigned short opt_shortname = sbi->options.shortname;
 482         int isvfat = sbi->options.isvfat;
 483         int nocase = sbi->options.nocase;
 484         const char *fill_name;
 485         unsigned long inum;
 486         unsigned long lpos, dummy, *furrfu = &lpos;
 487         loff_t cpos;
 488         int chi, chl, i, i2, j, last, last_u, dotoffset = 0, fill_len;
 489         int ret = 0;
 490
 491         lock_super(sb);
 492
 493         cpos = filp->f_pos;
 494         /* Fake . and .. for the root directory. */
 495         if (inode->i_ino == MSDOS_ROOT_INO) {
 496                 while (cpos < 2) {
 497                         if (filldir(dirent, "..", cpos+1, cpos, MSDOS_ROOT_INO, DT_DIR) < 0)
 498                                 goto out;
 499                         cpos++;
 500                         filp->f_pos++;
 501                 }
 502                 if (cpos == 2) {
 503                         dummy = 2;
 504                         furrfu = &dummy;
 505                         cpos = 0;
 506                 }
 507         }
 508         if (cpos & (sizeof(struct msdos_dir_entry) - 1)) {
 509                 ret = -ENOENT;
 510                 goto out;
 511         }
 512
 513         bh = NULL;
 514 get_new:
 515         if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
 516                 goto end_of_dir;
 517 parse_record:
 518         nr_slots = 0;
 519         /* Check for long filename entry */
 520         if (isvfat) {
 521                 if (de->name[0] == DELETED_FLAG)
 522                         goto record_end;
 523                 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
 524                         goto record_end;
 525                 if (de->attr != ATTR_EXT && IS_FREE(de->name))
 526                         goto record_end;
 527         } else {
 528                 if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
 529                         goto record_end;
 530         }
 531
 532         if (isvfat && de->attr == ATTR_EXT) {
 533                 int status = fat_parse_long(inode, &cpos, &bh, &de,
 534                                             &unicode, &nr_slots);
 535                 if (status < 0) {
 536                         filp->f_pos = cpos;
 537                         ret = status;
 538                         goto out;
 539                 } else if (status == PARSE_INVALID)
 540                         goto record_end;
 541                 else if (status == PARSE_NOT_LONGNAME)
 542                         goto parse_record;
 543                 else if (status == PARSE_EOF)
 544                         goto end_of_dir;
 545         }
 546
 547         if (sbi->options.dotsOK) {
 548                 ptname = bufname;
 549                 dotoffset = 0;
 550                 if (de->attr & ATTR_HIDDEN) {
 551                         *ptname++ = '.';
 552                         dotoffset = 1;
 553                 }
 554         }
 555
 556         memcpy(work, de->name, sizeof(de->name));
 557         /* see namei.c, msdos_format_name */
 558         if (work[0] == 0x05)
 559                 work[0] = 0xE5;
 560         for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
 561                 if (!(c = work[i]))
 562                         break;
 563                 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
 564                                         &bufuname[j++], opt_shortname,
 565                                         de->lcase & CASE_LOWER_BASE);
 566                 if (chl <= 1) {
 567                         ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
 568                         if (c != ' ') {
 569                                 last = i;
 570                                 last_u = j;
 571                         }
 572                 } else {
 573                         last_u = j;
 574                         for (chi = 0; chi < chl && i < 8; chi++) {
 575                                 ptname[i] = work[i];
 576                                 i++; last = i;
 577                         }
 578                 }
 579         }
 580         i = last;
 581         j = last_u;
 582         fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
 583         ptname[i++] = '.';
 584         for (i2 = 8; i2 < MSDOS_NAME;) {
 585                 if (!(c = work[i2]))
 586                         break;
 587                 chl = fat_shortname2uni(nls_disk, &work[i2], MSDOS_NAME - i2,
 588                                         &bufuname[j++], opt_shortname,
 589                                         de->lcase & CASE_LOWER_EXT);
 590                 if (chl <= 1) {
 591                         i2++;
 592                         ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
 593                         if (c != ' ') {
 594                                 last = i;
 595                                 last_u = j;
 596                         }
 597                 } else {
 598                         last_u = j;
 599                         for (chi = 0; chi < chl && i2 < MSDOS_NAME; chi++) {
 600                                 ptname[i++] = work[i2++];
 601                                 last = i;
 602                         }
 603                 }
 604         }
 605         if (!last)
 606                 goto record_end;
 607
 608         i = last + dotoffset;
 609         j = last_u;
 610
 611         lpos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry);
 612         if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME))
 613                 inum = inode->i_ino;
 614         else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
 615                 inum = parent_ino(filp->f_path.dentry);
 616         } else {
 617                 loff_t i_pos = fat_make_i_pos(sb, bh, de);
 618                 struct inode *tmp = fat_iget(sb, i_pos);
 619                 if (tmp) {
 620                         inum = tmp->i_ino;
 621                         iput(tmp);
 622                 } else
 623                         inum = iunique(sb, MSDOS_ROOT_INO);
 624         }
 625
 626         if (isvfat) {
 627                 bufuname[j] = 0x0000;
 628                 i = fat_uni_to_x8(sbi, bufuname, bufname, sizeof(bufname));
 629         }
 630
 631         fill_name = bufname;
 632         fill_len = i;
 633         if (!short_only && nr_slots) {
 634                 void *longname = unicode + FAT_MAX_UNI_CHARS;
 635                 int long_len, size = PATH_MAX - FAT_MAX_UNI_SIZE;
 636
 637                 long_len = fat_uni_to_x8(sbi, unicode, longname, size);
 638
 639                 if (!both) {
 640                         fill_name = longname;
 641                         fill_len = long_len;
 642                 } else {
 643                         /* hack for fat_ioctl_filldir() */
 644                         struct fat_ioctl_filldir_callback *p = dirent;
 645
 646                         p->longname = longname;
 647                         p->long_len = long_len;
 648                         p->shortname = bufname;
 649                         p->short_len = i;
 650                         fill_name = NULL;
 651                         fill_len = 0;
 652                 }
 653         }
 654         if (filldir(dirent, fill_name, fill_len, *furrfu, inum,
 655                     (de->attr & ATTR_DIR) ? DT_DIR : DT_REG) < 0)
 656                 goto fill_failed;
 657
 658 record_end:
 659         furrfu = &lpos;
 660         filp->f_pos = cpos;
 661         goto get_new;
 662 end_of_dir:
 663         filp->f_pos = cpos;
 664 fill_failed:
 665         brelse(bh);
 666         if (unicode)
 667                 __putname(unicode);
 668 out:
 669         unlock_super(sb);
 670         return ret;
 671 }
 672
 673 static int fat_readdir(struct file *filp, void *dirent, filldir_t filldir)
 674 {
 675         struct inode *inode = filp->f_path.dentry->d_inode;
 676         return __fat_readdir(inode, filp, dirent, filldir, 0, 0);
 677 }
 678
 679 #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type)                          \
 680 static int func(void *__buf, const char *name, int name_len,               \
 681                              loff_t offset, u64 ino, unsigned int d_type)  \
 682 {                                                                          \
 683         struct fat_ioctl_filldir_callback *buf = __buf;                    \
 684         struct dirent_type __user *d1 = buf->dirent;                       \
 685         struct dirent_type __user *d2 = d1 + 1;                            \
 686                                                                            \
 687         if (buf->result)                                                   \
 688                 return -EINVAL;                                            \
 689         buf->result++;                                                     \
 690                                                                            \
 691         if (name != NULL) {                                                \
 692                 /* dirent has only short name */                           \
 693                 if (name_len >= sizeof(d1->d_name))                        \
 694                         name_len = sizeof(d1->d_name) - 1;                 \
 695                                                                            \
 696                 if (put_user(0, d2->d_name)                     ||         \
 697                     put_user(0, &d2->d_reclen)                  ||         \
 698                     copy_to_user(d1->d_name, name, name_len)    ||         \
 699                     put_user(0, d1->d_name + name_len)          ||         \
 700                     put_user(name_len, &d1->d_reclen))                     \
 701                         goto efault;                                       \
 702         } else {                                                           \
 703                 /* dirent has short and long name */                       \
 704                 const char *longname = buf->longname;                      \
 705                 int long_len = buf->long_len;                              \
 706                 const char *shortname = buf->shortname;                    \
 707                 int short_len = buf->short_len;                            \
 708                                                                            \
 709                 if (long_len >= sizeof(d1->d_name))                        \
 710                         long_len = sizeof(d1->d_name) - 1;                 \
 711                 if (short_len >= sizeof(d1->d_name))                       \
 712                         short_len = sizeof(d1->d_name) - 1;                \
 713                                                                            \
 714                 if (copy_to_user(d2->d_name, longname, long_len)        || \
 715                     put_user(0, d2->d_name + long_len)                  || \
 716                     put_user(long_len, &d2->d_reclen)                   || \
 717                     put_user(ino, &d2->d_ino)                           || \
 718                     put_user(offset, &d2->d_off)                        || \
 719                     copy_to_user(d1->d_name, shortname, short_len)      || \
 720                     put_user(0, d1->d_name + short_len)                 || \
 721                     put_user(short_len, &d1->d_reclen))                    \
 722                         goto efault;                                       \
 723         }                                                                  \
 724         return 0;                                                          \
 725 efault:                                                                    \
 726         buf->result = -EFAULT;                                             \
 727         return -EFAULT;                                                    \
 728 }
 729
 730 FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent)
 731
 732 static int fat_ioctl_readdir(struct inode *inode, struct file *filp,
 733                              void __user *dirent, filldir_t filldir,
 734                              int short_only, int both)
 735 {
 736         struct fat_ioctl_filldir_callback buf;
 737         int ret;
 738
 739         buf.dirent = dirent;
 740         buf.result = 0;
 741         mutex_lock(&inode->i_mutex);
 742         ret = -ENOENT;
 743         if (!IS_DEADDIR(inode)) {
 744                 ret = __fat_readdir(inode, filp, &buf, filldir,
 745                                     short_only, both);
 746         }
 747         mutex_unlock(&inode->i_mutex);
 748         if (ret >= 0)
 749                 ret = buf.result;
 750         return ret;
 751 }
 752
 753 static int fat_dir_ioctl(struct inode *inode, struct file *filp,
 754                          unsigned int cmd, unsigned long arg)
 755 {
 756         struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg;
 757         int short_only, both;
 758
 759         switch (cmd) {
 760         case VFAT_IOCTL_READDIR_SHORT:
 761                 short_only = 1;
 762                 both = 0;
 763                 break;
 764         case VFAT_IOCTL_READDIR_BOTH:
 765                 short_only = 0;
 766                 both = 1;
 767                 break;
 768         default:
 769                 return fat_generic_ioctl(inode, filp, cmd, arg);
 770         }
 771
 772         if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_dirent[2])))
 773                 return -EFAULT;
 774         /*
 775          * Yes, we don't need this put_user() absolutely. However old
 776          * code didn't return the right value. So, app use this value,
 777          * in order to check whether it is EOF.
 778          */
 779         if (put_user(0, &d1->d_reclen))
 780                 return -EFAULT;
 781
 782         return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir,
 783                                  short_only, both);
 784 }
 785
 786 #ifdef CONFIG_COMPAT
 787 #define VFAT_IOCTL_READDIR_BOTH32       _IOR('r', 1, struct compat_dirent[2])
 788 #define VFAT_IOCTL_READDIR_SHORT32      _IOR('r', 2, struct compat_dirent[2])
 789
 790 FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
 791
 792 static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
 793                                  unsigned long arg)
 794 {
 795         struct inode *inode = filp->f_path.dentry->d_inode;
 796         struct compat_dirent __user *d1 = compat_ptr(arg);
 797         int short_only, both;
 798
 799         switch (cmd) {
 800         case VFAT_IOCTL_READDIR_SHORT32:
 801                 short_only = 1;
 802                 both = 0;
 803                 break;
 804         case VFAT_IOCTL_READDIR_BOTH32:
 805                 short_only = 0;
 806                 both = 1;
 807                 break;
 808         default:
 809                 return -ENOIOCTLCMD;
 810         }
 811
 812         if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_dirent[2])))
 813                 return -EFAULT;
 814         /*
 815          * Yes, we don't need this put_user() absolutely. However old
 816          * code didn't return the right value. So, app use this value,
 817          * in order to check whether it is EOF.
 818          */
 819         if (put_user(0, &d1->d_reclen))
 820                 return -EFAULT;
 821
 822         return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir,
 823                                  short_only, both);
 824 }
 825 #endif /* CONFIG_COMPAT */
 826
 827 const struct file_operations fat_dir_operations = {
 828         .read           = generic_read_dir,
 829         .readdir        = fat_readdir,
 830         .ioctl          = fat_dir_ioctl,
 831 #ifdef CONFIG_COMPAT
 832         .compat_ioctl   = fat_compat_dir_ioctl,
 833 #endif
 834         .fsync          = file_fsync,
 835 };
 836
 837 static int fat_get_short_entry(struct inode *dir, loff_t *pos,
 838                                struct buffer_head **bh,
 839                                struct msdos_dir_entry **de)
 840 {
 841         while (fat_get_entry(dir, pos, bh, de) >= 0) {
 842                 /* free entry or long name entry or volume label */
 843                 if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
 844                         return 0;
 845         }
 846         return -ENOENT;
 847 }
 848
 849 /*
 850  * The ".." entry can not provide the "struct fat_slot_info" informations
 851  * for inode. So, this function provide the some informations only.
 852  */
 853 int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
 854                          struct msdos_dir_entry **de, loff_t *i_pos)
 855 {
 856         loff_t offset;
 857
 858         offset = 0;
 859         *bh = NULL;
 860         while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
 861                 if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) {
 862                         *i_pos = fat_make_i_pos(dir->i_sb, *bh, *de);
 863                         return 0;
 864                 }
 865         }
 866         return -ENOENT;
 867 }
 868
 869 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
 870
 871 /* See if directory is empty */
 872 int fat_dir_empty(struct inode *dir)
 873 {
 874         struct buffer_head *bh;
 875         struct msdos_dir_entry *de;
 876         loff_t cpos;
 877         int result = 0;
 878
 879         bh = NULL;
 880         cpos = 0;
 881         while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
 882                 if (strncmp(de->name, MSDOS_DOT   , MSDOS_NAME) &&
 883                     strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
 884                         result = -ENOTEMPTY;
 885                         break;
 886                 }
 887         }
 888         brelse(bh);
 889         return result;
 890 }
 891
 892 EXPORT_SYMBOL_GPL(fat_dir_empty);
 893
 894 /*
 895  * fat_subdirs counts the number of sub-directories of dir. It can be run
 896  * on directories being created.
 897  */
 898 int fat_subdirs(struct inode *dir)
 899 {
 900         struct buffer_head *bh;
 901         struct msdos_dir_entry *de;
 902         loff_t cpos;
 903         int count = 0;
 904
 905         bh = NULL;
 906         cpos = 0;
 907         while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
 908                 if (de->attr & ATTR_DIR)
 909                         count++;
 910         }
 911         brelse(bh);
 912         return count;
 913 }
 914
 915 /*
 916  * Scans a directory for a given file (name points to its formatted name).
 917  * Returns an error code or zero.
 918  */
 919 int fat_scan(struct inode *dir, const unsigned char *name,
 920              struct fat_slot_info *sinfo)
 921 {
 922         struct super_block *sb = dir->i_sb;
 923
 924         sinfo->slot_off = 0;
 925         sinfo->bh = NULL;
 926         while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
 927                                    &sinfo->de) >= 0) {
 928                 if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
 929                         sinfo->slot_off -= sizeof(*sinfo->de);
 930                         sinfo->nr_slots = 1;
 931                         sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
 932                         return 0;
 933                 }
 934         }
 935         return -ENOENT;
 936 }
 937
 938 EXPORT_SYMBOL_GPL(fat_scan);
 939
 940 static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
 941 {
 942         struct super_block *sb = dir->i_sb;
 943         struct buffer_head *bh;
 944         struct msdos_dir_entry *de, *endp;
 945         int err = 0, orig_slots;
 946
 947         while (nr_slots) {
 948                 bh = NULL;
 949                 if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
 950                         err = -EIO;
 951                         break;
 952                 }
 953
 954                 orig_slots = nr_slots;
 955                 endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
 956                 while (nr_slots && de < endp) {
 957                         de->name[0] = DELETED_FLAG;
 958                         de++;
 959                         nr_slots--;
 960                 }
 961                 mark_buffer_dirty(bh);
 962                 if (IS_DIRSYNC(dir))
 963                         err = sync_dirty_buffer(bh);
 964                 brelse(bh);
 965                 if (err)
 966                         break;
 967
 968                 /* pos is *next* de's position, so this does `- sizeof(de)' */
 969                 pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
 970         }
 971
 972         return err;
 973 }
 974
 975 int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
 976 {
 977         struct msdos_dir_entry *de;
 978         struct buffer_head *bh;
 979         int err = 0, nr_slots;
 980
 981         /*
 982          * First stage: Remove the shortname. By this, the directory
 983          * entry is removed.
 984          */
 985         nr_slots = sinfo->nr_slots;
 986         de = sinfo->de;
 987         sinfo->de = NULL;
 988         bh = sinfo->bh;
 989         sinfo->bh = NULL;
 990         while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
 991                 de->name[0] = DELETED_FLAG;
 992                 de--;
 993                 nr_slots--;
 994         }
 995         mark_buffer_dirty(bh);
 996         if (IS_DIRSYNC(dir))
 997                 err = sync_dirty_buffer(bh);
 998         brelse(bh);
 999         if (err)
1000                 return err;
1001         dir->i_version++;
1002
1003         if (nr_slots) {
1004                 /*
1005                  * Second stage: remove the remaining longname slots.
1006                  * (This directory entry is already removed, and so return
1007                  * the success)
1008                  */
1009                 err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
1010                 if (err) {
1011                         printk(KERN_WARNING
1012                                "FAT: Couldn't remove the long name slots\n");
1013                 }
1014         }
1015
1016         dir->i_mtime = dir->i_atime = CURRENT_TIME_SEC;
1017         if (IS_DIRSYNC(dir))
1018                 (void)fat_sync_inode(dir);
1019         else
1020                 mark_inode_dirty(dir);
1021
1022         return 0;
1023 }
1024
1025 EXPORT_SYMBOL_GPL(fat_remove_entries);
1026
1027 static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
1028                               struct buffer_head **bhs, int nr_bhs)
1029 {
1030         struct super_block *sb = dir->i_sb;
1031         sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
1032         int err, i, n;
1033
1034         /* Zeroing the unused blocks on this cluster */
1035         blknr += nr_used;
1036         n = nr_used;
1037         while (blknr < last_blknr) {
1038                 bhs[n] = sb_getblk(sb, blknr);
1039                 if (!bhs[n]) {
1040                         err = -ENOMEM;
1041                         goto error;
1042                 }
1043                 memset(bhs[n]->b_data, 0, sb->s_blocksize);
1044                 set_buffer_uptodate(bhs[n]);
1045                 mark_buffer_dirty(bhs[n]);
1046
1047                 n++;
1048                 blknr++;
1049                 if (n == nr_bhs) {
1050                         if (IS_DIRSYNC(dir)) {
1051                                 err = fat_sync_bhs(bhs, n);
1052                                 if (err)
1053                                         goto error;
1054                         }
1055                         for (i = 0; i < n; i++)
1056                                 brelse(bhs[i]);
1057                         n = 0;
1058                 }
1059         }
1060         if (IS_DIRSYNC(dir)) {
1061                 err = fat_sync_bhs(bhs, n);
1062                 if (err)
1063                         goto error;
1064         }
1065         for (i = 0; i < n; i++)
1066                 brelse(bhs[i]);
1067
1068         return 0;
1069
1070 error:
1071         for (i = 0; i < n; i++)
1072                 bforget(bhs[i]);
1073         return err;
1074 }
1075
1076 int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
1077 {
1078         struct super_block *sb = dir->i_sb;
1079         struct msdos_sb_info *sbi = MSDOS_SB(sb);
1080         struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1081         struct msdos_dir_entry *de;
1082         sector_t blknr;
1083         __le16 date, time;
1084         int err, cluster;
1085
1086         err = fat_alloc_clusters(dir, &cluster, 1);
1087         if (err)
1088                 goto error;
1089
1090         blknr = fat_clus_to_blknr(sbi, cluster);
1091         bhs[0] = sb_getblk(sb, blknr);
1092         if (!bhs[0]) {
1093                 err = -ENOMEM;
1094                 goto error_free;
1095         }
1096
1097         fat_date_unix2dos(ts->tv_sec, &time, &date);
1098
1099         de = (struct msdos_dir_entry *)bhs[0]->b_data;
1100         /* filling the new directory slots ("." and ".." entries) */
1101         memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
1102         memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
1103         de->attr = de[1].attr = ATTR_DIR;
1104         de[0].lcase = de[1].lcase = 0;
1105         de[0].time = de[1].time = time;
1106         de[0].date = de[1].date = date;
1107         de[0].ctime_cs = de[1].ctime_cs = 0;
1108         if (sbi->options.isvfat) {
1109                 /* extra timestamps */
1110                 de[0].ctime = de[1].ctime = time;
1111                 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
1112         } else {
1113                 de[0].ctime = de[1].ctime = 0;
1114                 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
1115         }
1116         de[0].start = cpu_to_le16(cluster);
1117         de[0].starthi = cpu_to_le16(cluster >> 16);
1118         de[1].start = cpu_to_le16(MSDOS_I(dir)->i_logstart);
1119         de[1].starthi = cpu_to_le16(MSDOS_I(dir)->i_logstart >> 16);
1120         de[0].size = de[1].size = 0;
1121         memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
1122         set_buffer_uptodate(bhs[0]);
1123         mark_buffer_dirty(bhs[0]);
1124
1125         err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
1126         if (err)
1127                 goto error_free;
1128
1129         return cluster;
1130
1131 error_free:
1132         fat_free_clusters(dir, cluster);
1133 error:
1134         return err;
1135 }
1136
1137 EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
1138
1139 static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
1140                                int *nr_cluster, struct msdos_dir_entry **de,
1141                                struct buffer_head **bh, loff_t *i_pos)
1142 {
1143         struct super_block *sb = dir->i_sb;
1144         struct msdos_sb_info *sbi = MSDOS_SB(sb);
1145         struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1146         sector_t blknr, start_blknr, last_blknr;
1147         unsigned long size, copy;
1148         int err, i, n, offset, cluster[2];
1149
1150         /*
1151          * The minimum cluster size is 512bytes, and maximum entry
1152          * size is 32*slots (672bytes).  So, iff the cluster size is
1153          * 512bytes, we may need two clusters.
1154          */
1155         size = nr_slots * sizeof(struct msdos_dir_entry);
1156         *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
1157         BUG_ON(*nr_cluster > 2);
1158
1159         err = fat_alloc_clusters(dir, cluster, *nr_cluster);
1160         if (err)
1161                 goto error;
1162
1163         /*
1164          * First stage: Fill the directory entry.  NOTE: This cluster
1165          * is not referenced from any inode yet, so updates order is
1166          * not important.
1167          */
1168         i = n = copy = 0;
1169         do {
1170                 start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
1171                 last_blknr = start_blknr + sbi->sec_per_clus;
1172                 while (blknr < last_blknr) {
1173                         bhs[n] = sb_getblk(sb, blknr);
1174                         if (!bhs[n]) {
1175                                 err = -ENOMEM;
1176                                 goto error_nomem;
1177                         }
1178
1179                         /* fill the directory entry */
1180                         copy = min(size, sb->s_blocksize);
1181                         memcpy(bhs[n]->b_data, slots, copy);
1182                         slots += copy;
1183                         size -= copy;
1184                         set_buffer_uptodate(bhs[n]);
1185                         mark_buffer_dirty(bhs[n]);
1186                         if (!size)
1187                                 break;
1188                         n++;
1189                         blknr++;
1190                 }
1191         } while (++i < *nr_cluster);
1192
1193         memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
1194         offset = copy - sizeof(struct msdos_dir_entry);
1195         get_bh(bhs[n]);
1196         *bh = bhs[n];
1197         *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
1198         *i_pos = fat_make_i_pos(sb, *bh, *de);
1199
1200         /* Second stage: clear the rest of cluster, and write outs */
1201         err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
1202         if (err)
1203                 goto error_free;
1204
1205         return cluster[0];
1206
1207 error_free:
1208         brelse(*bh);
1209         *bh = NULL;
1210         n = 0;
1211 error_nomem:
1212         for (i = 0; i < n; i++)
1213                 bforget(bhs[i]);
1214         fat_free_clusters(dir, cluster[0]);
1215 error:
1216         return err;
1217 }
1218
1219 int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
1220                     struct fat_slot_info *sinfo)
1221 {
1222         struct super_block *sb = dir->i_sb;
1223         struct msdos_sb_info *sbi = MSDOS_SB(sb);
1224         struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
1225         struct msdos_dir_entry *de;
1226         int err, free_slots, i, nr_bhs;
1227         loff_t pos, i_pos;
1228
1229         sinfo->nr_slots = nr_slots;
1230
1231         /* First stage: search free direcotry entries */
1232         free_slots = nr_bhs = 0;
1233         bh = prev = NULL;
1234         pos = 0;
1235         err = -ENOSPC;
1236         while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
1237                 /* check the maximum size of directory */
1238                 if (pos >= FAT_MAX_DIR_SIZE)
1239                         goto error;
1240
1241                 if (IS_FREE(de->name)) {
1242                         if (prev != bh) {
1243                                 get_bh(bh);
1244                                 bhs[nr_bhs] = prev = bh;
1245                                 nr_bhs++;
1246                         }
1247                         free_slots++;
1248                         if (free_slots == nr_slots)
1249                                 goto found;
1250                 } else {
1251                         for (i = 0; i < nr_bhs; i++)
1252                                 brelse(bhs[i]);
1253                         prev = NULL;
1254                         free_slots = nr_bhs = 0;
1255                 }
1256         }
1257         if (dir->i_ino == MSDOS_ROOT_INO) {
1258                 if (sbi->fat_bits != 32)
1259                         goto error;
1260         } else if (MSDOS_I(dir)->i_start == 0) {
1261                 printk(KERN_ERR "FAT: Corrupted directory (i_pos %lld)\n",
1262                        MSDOS_I(dir)->i_pos);
1263                 err = -EIO;
1264                 goto error;
1265         }
1266
1267 found:
1268         err = 0;
1269         pos -= free_slots * sizeof(*de);
1270         nr_slots -= free_slots;
1271         if (free_slots) {
1272                 /*
1273                  * Second stage: filling the free entries with new entries.
1274                  * NOTE: If this slots has shortname, first, we write
1275                  * the long name slots, then write the short name.
1276                  */
1277                 int size = free_slots * sizeof(*de);
1278                 int offset = pos & (sb->s_blocksize - 1);
1279                 int long_bhs = nr_bhs - (nr_slots == 0);
1280
1281                 /* Fill the long name slots. */
1282                 for (i = 0; i < long_bhs; i++) {
1283                         int copy = min_t(int, sb->s_blocksize - offset, size);
1284                         memcpy(bhs[i]->b_data + offset, slots, copy);
1285                         mark_buffer_dirty(bhs[i]);
1286                         offset = 0;
1287                         slots += copy;
1288                         size -= copy;
1289                 }
1290                 if (long_bhs && IS_DIRSYNC(dir))
1291                         err = fat_sync_bhs(bhs, long_bhs);
1292                 if (!err && i < nr_bhs) {
1293                         /* Fill the short name slot. */
1294                         int copy = min_t(int, sb->s_blocksize - offset, size);
1295                         memcpy(bhs[i]->b_data + offset, slots, copy);
1296                         mark_buffer_dirty(bhs[i]);
1297                         if (IS_DIRSYNC(dir))
1298                                 err = sync_dirty_buffer(bhs[i]);
1299                 }
1300                 for (i = 0; i < nr_bhs; i++)
1301                         brelse(bhs[i]);
1302                 if (err)
1303                         goto error_remove;
1304         }
1305
1306         if (nr_slots) {
1307                 int cluster, nr_cluster;
1308
1309                 /*
1310                  * Third stage: allocate the cluster for new entries.
1311                  * And initialize the cluster with new entries, then
1312                  * add the cluster to dir.
1313                  */
1314                 cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
1315                                               &de, &bh, &i_pos);
1316                 if (cluster < 0) {
1317                         err = cluster;
1318                         goto error_remove;
1319                 }
1320                 err = fat_chain_add(dir, cluster, nr_cluster);
1321                 if (err) {
1322                         fat_free_clusters(dir, cluster);
1323                         goto error_remove;
1324                 }
1325                 if (dir->i_size & (sbi->cluster_size - 1)) {
1326                         fat_fs_panic(sb, "Odd directory size");
1327                         dir->i_size = (dir->i_size + sbi->cluster_size - 1)
1328                                 & ~((loff_t)sbi->cluster_size - 1);
1329                 }
1330                 dir->i_size += nr_cluster << sbi->cluster_bits;
1331                 MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
1332         }
1333         sinfo->slot_off = pos;
1334         sinfo->de = de;
1335         sinfo->bh = bh;
1336         sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
1337
1338         return 0;
1339
1340 error:
1341         brelse(bh);
1342         for (i = 0; i < nr_bhs; i++)
1343                 brelse(bhs[i]);
1344         return err;
1345
1346 error_remove:
1347         brelse(bh);
1348         if (free_slots)
1349                 __fat_remove_entries(dir, pos, free_slots);
1350         return err;
1351 }
1352
1353 EXPORT_SYMBOL_GPL(fat_add_entries);