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