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[8], 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]) break;
 355                         chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
 356                                                 &bufuname[j++], opt_shortname,
 357                                                 de->lcase & CASE_LOWER_BASE);
 358                         if (chl <= 1) {
 359                                 if (work[i] != ' ')
 360                                         last_u = j;
 361                         } else {
 362                                 last_u = j;
 363                         }
 364                         i += chl;
 365                 }
 366                 j = last_u;
 367                 fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
 368                 for (i = 0; i < 3;) {
 369                         if (!de->ext[i]) break;
 370                         chl = fat_shortname2uni(nls_disk, &de->ext[i], 3 - i,
 371                                                 &bufuname[j++], opt_shortname,
 372                                                 de->lcase & CASE_LOWER_EXT);
 373                         if (chl <= 1) {
 374                                 if (de->ext[i] != ' ')
 375                                         last_u = j;
 376                         } else {
 377                                 last_u = j;
 378                         }
 379                         i += chl;
 380                 }
 381                 if (!last_u)
 382                         continue;
 383
 384                 bufuname[last_u] = 0x0000;
 385                 xlate_len = utf8
 386                         ?utf8_wcstombs(bufname, bufuname, sizeof(bufname))
 387                         :uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
 388                 if (xlate_len == name_len)
 389                         if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
 390                             (anycase && !nls_strnicmp(nls_io, name, bufname,
 391                                                                 xlate_len)))
 392                                 goto Found;
 393
 394                 if (nr_slots) {
 395                         xlate_len = utf8
 396                                 ?utf8_wcstombs(bufname, unicode, sizeof(bufname))
 397                                 :uni16_to_x8(bufname, unicode, uni_xlate, nls_io);
 398                         if (xlate_len != name_len)
 399                                 continue;
 400                         if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
 401                             (anycase && !nls_strnicmp(nls_io, name, bufname,
 402                                                                 xlate_len)))
 403                                 goto Found;
 404                 }
 405         }
 406
 407 Found:
 408         nr_slots++;     /* include the de */
 409         sinfo->slot_off = cpos - nr_slots * sizeof(*de);
 410         sinfo->nr_slots = nr_slots;
 411         sinfo->de = de;
 412         sinfo->bh = bh;
 413         sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
 414         err = 0;
 415 EODir:
 416         if (unicode)
 417                 free_page((unsigned long)unicode);
 418
 419         return err;
 420 }
 421
 422 EXPORT_SYMBOL_GPL(fat_search_long);
 423
 424 struct fat_ioctl_filldir_callback {
 425         void __user *dirent;
 426         int result;
 427         /* for dir ioctl */
 428         const char *longname;
 429         int long_len;
 430         const char *shortname;
 431         int short_len;
 432 };
 433
 434 static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent,
 435                          filldir_t filldir, int short_only, int both)
 436 {
 437         struct super_block *sb = inode->i_sb;
 438         struct msdos_sb_info *sbi = MSDOS_SB(sb);
 439         struct buffer_head *bh;
 440         struct msdos_dir_entry *de;
 441         struct nls_table *nls_io = sbi->nls_io;
 442         struct nls_table *nls_disk = sbi->nls_disk;
 443         unsigned char long_slots;
 444         const char *fill_name;
 445         int fill_len;
 446         wchar_t bufuname[14];
 447         wchar_t *unicode = NULL;
 448         unsigned char c, work[8], bufname[56], *ptname = bufname;
 449         unsigned long lpos, dummy, *furrfu = &lpos;
 450         int uni_xlate = sbi->options.unicode_xlate;
 451         int isvfat = sbi->options.isvfat;
 452         int utf8 = sbi->options.utf8;
 453         int nocase = sbi->options.nocase;
 454         unsigned short opt_shortname = sbi->options.shortname;
 455         unsigned long inum;
 456         int chi, chl, i, i2, j, last, last_u, dotoffset = 0;
 457         loff_t cpos;
 458         int ret = 0;
 459
 460         lock_kernel();
 461
 462         cpos = filp->f_pos;
 463         /* Fake . and .. for the root directory. */
 464         if (inode->i_ino == MSDOS_ROOT_INO) {
 465                 while (cpos < 2) {
 466                         if (filldir(dirent, "..", cpos+1, cpos, MSDOS_ROOT_INO, DT_DIR) < 0)
 467                                 goto out;
 468                         cpos++;
 469                         filp->f_pos++;
 470                 }
 471                 if (cpos == 2) {
 472                         dummy = 2;
 473                         furrfu = &dummy;
 474                         cpos = 0;
 475                 }
 476         }
 477         if (cpos & (sizeof(struct msdos_dir_entry)-1)) {
 478                 ret = -ENOENT;
 479                 goto out;
 480         }
 481
 482         bh = NULL;
 483 GetNew:
 484         if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
 485                 goto EODir;
 486 parse_record:
 487         long_slots = 0;
 488         /* Check for long filename entry */
 489         if (isvfat) {
 490                 if (de->name[0] == DELETED_FLAG)
 491                         goto RecEnd;
 492                 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
 493                         goto RecEnd;
 494                 if (de->attr != ATTR_EXT && IS_FREE(de->name))
 495                         goto RecEnd;
 496         } else {
 497                 if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
 498                         goto RecEnd;
 499         }
 500
 501         if (isvfat && de->attr == ATTR_EXT) {
 502                 int status = fat_parse_long(inode, &cpos, &bh, &de,
 503                                             &unicode, &long_slots);
 504                 if (status < 0) {
 505                         filp->f_pos = cpos;
 506                         ret = status;
 507                         goto out;
 508                 } else if (status == PARSE_INVALID)
 509                         goto RecEnd;
 510                 else if (status == PARSE_NOT_LONGNAME)
 511                         goto parse_record;
 512                 else if (status == PARSE_EOF)
 513                         goto EODir;
 514         }
 515
 516         if (sbi->options.dotsOK) {
 517                 ptname = bufname;
 518                 dotoffset = 0;
 519                 if (de->attr & ATTR_HIDDEN) {
 520                         *ptname++ = '.';
 521                         dotoffset = 1;
 522                 }
 523         }
 524
 525         memcpy(work, de->name, sizeof(de->name));
 526         /* see namei.c, msdos_format_name */
 527         if (work[0] == 0x05)
 528                 work[0] = 0xE5;
 529         for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
 530                 if (!(c = work[i])) break;
 531                 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
 532                                         &bufuname[j++], opt_shortname,
 533                                         de->lcase & CASE_LOWER_BASE);
 534                 if (chl <= 1) {
 535                         ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
 536                         if (c != ' ') {
 537                                 last = i;
 538                                 last_u = j;
 539                         }
 540                 } else {
 541                         last_u = j;
 542                         for (chi = 0; chi < chl && i < 8; chi++) {
 543                                 ptname[i] = work[i];
 544                                 i++; last = i;
 545                         }
 546                 }
 547         }
 548         i = last;
 549         j = last_u;
 550         fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
 551         ptname[i++] = '.';
 552         for (i2 = 0; i2 < 3;) {
 553                 if (!(c = de->ext[i2])) break;
 554                 chl = fat_shortname2uni(nls_disk, &de->ext[i2], 3 - i2,
 555                                         &bufuname[j++], opt_shortname,
 556                                         de->lcase & CASE_LOWER_EXT);
 557                 if (chl <= 1) {
 558                         i2++;
 559                         ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
 560                         if (c != ' ') {
 561                                 last = i;
 562                                 last_u = j;
 563                         }
 564                 } else {
 565                         last_u = j;
 566                         for (chi = 0; chi < chl && i2 < 3; chi++) {
 567                                 ptname[i++] = de->ext[i2++];
 568                                 last = i;
 569                         }
 570                 }
 571         }
 572         if (!last)
 573                 goto RecEnd;
 574
 575         i = last + dotoffset;
 576         j = last_u;
 577
 578         lpos = cpos - (long_slots+1)*sizeof(struct msdos_dir_entry);
 579         if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME))
 580                 inum = inode->i_ino;
 581         else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
 582                 inum = parent_ino(filp->f_path.dentry);
 583         } else {
 584                 loff_t i_pos = fat_make_i_pos(sb, bh, de);
 585                 struct inode *tmp = fat_iget(sb, i_pos);
 586                 if (tmp) {
 587                         inum = tmp->i_ino;
 588                         iput(tmp);
 589                 } else
 590                         inum = iunique(sb, MSDOS_ROOT_INO);
 591         }
 592
 593         if (isvfat) {
 594                 bufuname[j] = 0x0000;
 595                 i = utf8 ? utf8_wcstombs(bufname, bufuname, sizeof(bufname))
 596                          : uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
 597         }
 598
 599         fill_name = bufname;
 600         fill_len = i;
 601         if (!short_only && long_slots) {
 602                 /* convert the unicode long name. 261 is maximum size
 603                  * of unicode buffer. (13 * slots + nul) */
 604                 void *longname = unicode + 261;
 605                 int buf_size = PAGE_SIZE - (261 * sizeof(unicode[0]));
 606                 int long_len = utf8
 607                         ? utf8_wcstombs(longname, unicode, buf_size)
 608                         : uni16_to_x8(longname, unicode, uni_xlate, nls_io);
 609
 610                 if (!both) {
 611                         fill_name = longname;
 612                         fill_len = long_len;
 613                 } else {
 614                         /* hack for fat_ioctl_filldir() */
 615                         struct fat_ioctl_filldir_callback *p = dirent;
 616
 617                         p->longname = longname;
 618                         p->long_len = long_len;
 619                         p->shortname = bufname;
 620                         p->short_len = i;
 621                         fill_name = NULL;
 622                         fill_len = 0;
 623                 }
 624         }
 625         if (filldir(dirent, fill_name, fill_len, *furrfu, inum,
 626                     (de->attr & ATTR_DIR) ? DT_DIR : DT_REG) < 0)
 627                 goto FillFailed;
 628
 629 RecEnd:
 630         furrfu = &lpos;
 631         filp->f_pos = cpos;
 632         goto GetNew;
 633 EODir:
 634         filp->f_pos = cpos;
 635 FillFailed:
 636         brelse(bh);
 637         if (unicode)
 638                 free_page((unsigned long)unicode);
 639 out:
 640         unlock_kernel();
 641         return ret;
 642 }
 643
 644 static int fat_readdir(struct file *filp, void *dirent, filldir_t filldir)
 645 {
 646         struct inode *inode = filp->f_path.dentry->d_inode;
 647         return __fat_readdir(inode, filp, dirent, filldir, 0, 0);
 648 }
 649
 650 #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type)                          \
 651 static int func(void *__buf, const char *name, int name_len,               \
 652                              loff_t offset, u64 ino, unsigned int d_type)  \
 653 {                                                                          \
 654         struct fat_ioctl_filldir_callback *buf = __buf;                    \
 655         struct dirent_type __user *d1 = buf->dirent;                       \
 656         struct dirent_type __user *d2 = d1 + 1;                            \
 657                                                                            \
 658         if (buf->result)                                                   \
 659                 return -EINVAL;                                            \
 660         buf->result++;                                                     \
 661                                                                            \
 662         if (name != NULL) {                                                \
 663                 /* dirent has only short name */                           \
 664                 if (name_len >= sizeof(d1->d_name))                        \
 665                         name_len = sizeof(d1->d_name) - 1;                 \
 666                                                                            \
 667                 if (put_user(0, d2->d_name)                     ||         \
 668                     put_user(0, &d2->d_reclen)                  ||         \
 669                     copy_to_user(d1->d_name, name, name_len)    ||         \
 670                     put_user(0, d1->d_name + name_len)          ||         \
 671                     put_user(name_len, &d1->d_reclen))                     \
 672                         goto efault;                                       \
 673         } else {                                                           \
 674                 /* dirent has short and long name */                       \
 675                 const char *longname = buf->longname;                      \
 676                 int long_len = buf->long_len;                              \
 677                 const char *shortname = buf->shortname;                    \
 678                 int short_len = buf->short_len;                            \
 679                                                                            \
 680                 if (long_len >= sizeof(d1->d_name))                        \
 681                         long_len = sizeof(d1->d_name) - 1;                 \
 682                 if (short_len >= sizeof(d1->d_name))                       \
 683                         short_len = sizeof(d1->d_name) - 1;                \
 684                                                                            \
 685                 if (copy_to_user(d2->d_name, longname, long_len)        || \
 686                     put_user(0, d2->d_name + long_len)                  || \
 687                     put_user(long_len, &d2->d_reclen)                   || \
 688                     put_user(ino, &d2->d_ino)                           || \
 689                     put_user(offset, &d2->d_off)                        || \
 690                     copy_to_user(d1->d_name, shortname, short_len)      || \
 691                     put_user(0, d1->d_name + short_len)                 || \
 692                     put_user(short_len, &d1->d_reclen))                    \
 693                         goto efault;                                       \
 694         }                                                                  \
 695         return 0;                                                          \
 696 efault:                                                                    \
 697         buf->result = -EFAULT;                                             \
 698         return -EFAULT;                                                    \
 699 }
 700
 701 FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, dirent)
 702
 703 static int fat_ioctl_readdir(struct inode *inode, struct file *filp,
 704                              void __user *dirent, filldir_t filldir,
 705                              int short_only, int both)
 706 {
 707         struct fat_ioctl_filldir_callback buf;
 708         int ret;
 709
 710         buf.dirent = dirent;
 711         buf.result = 0;
 712         mutex_lock(&inode->i_mutex);
 713         ret = -ENOENT;
 714         if (!IS_DEADDIR(inode)) {
 715                 ret = __fat_readdir(inode, filp, &buf, filldir,
 716                                     short_only, both);
 717         }
 718         mutex_unlock(&inode->i_mutex);
 719         if (ret >= 0)
 720                 ret = buf.result;
 721         return ret;
 722 }
 723
 724 static int fat_dir_ioctl(struct inode *inode, struct file *filp,
 725                          unsigned int cmd, unsigned long arg)
 726 {
 727         struct dirent __user *d1 = (struct dirent __user *)arg;
 728         int short_only, both;
 729
 730         switch (cmd) {
 731         case VFAT_IOCTL_READDIR_SHORT:
 732                 short_only = 1;
 733                 both = 0;
 734                 break;
 735         case VFAT_IOCTL_READDIR_BOTH:
 736                 short_only = 0;
 737                 both = 1;
 738                 break;
 739         default:
 740                 return fat_generic_ioctl(inode, filp, cmd, arg);
 741         }
 742
 743         if (!access_ok(VERIFY_WRITE, d1, sizeof(struct dirent[2])))
 744                 return -EFAULT;
 745         /*
 746          * Yes, we don't need this put_user() absolutely. However old
 747          * code didn't return the right value. So, app use this value,
 748          * in order to check whether it is EOF.
 749          */
 750         if (put_user(0, &d1->d_reclen))
 751                 return -EFAULT;
 752
 753         return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir,
 754                                  short_only, both);
 755 }
 756
 757 #ifdef CONFIG_COMPAT
 758 #define VFAT_IOCTL_READDIR_BOTH32       _IOR('r', 1, struct compat_dirent[2])
 759 #define VFAT_IOCTL_READDIR_SHORT32      _IOR('r', 2, struct compat_dirent[2])
 760
 761 FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
 762
 763 static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
 764                                  unsigned long arg)
 765 {
 766         struct inode *inode = filp->f_path.dentry->d_inode;
 767         struct compat_dirent __user *d1 = compat_ptr(arg);
 768         int short_only, both;
 769
 770         switch (cmd) {
 771         case VFAT_IOCTL_READDIR_SHORT32:
 772                 short_only = 1;
 773                 both = 0;
 774                 break;
 775         case VFAT_IOCTL_READDIR_BOTH32:
 776                 short_only = 0;
 777                 both = 1;
 778                 break;
 779         default:
 780                 return -ENOIOCTLCMD;
 781         }
 782
 783         if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_dirent[2])))
 784                 return -EFAULT;
 785         /*
 786          * Yes, we don't need this put_user() absolutely. However old
 787          * code didn't return the right value. So, app use this value,
 788          * in order to check whether it is EOF.
 789          */
 790         if (put_user(0, &d1->d_reclen))
 791                 return -EFAULT;
 792
 793         return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir,
 794                                  short_only, both);
 795 }
 796 #endif /* CONFIG_COMPAT */
 797
 798 const struct file_operations fat_dir_operations = {
 799         .read           = generic_read_dir,
 800         .readdir        = fat_readdir,
 801         .ioctl          = fat_dir_ioctl,
 802 #ifdef CONFIG_COMPAT
 803         .compat_ioctl   = fat_compat_dir_ioctl,
 804 #endif
 805         .fsync          = file_fsync,
 806 };
 807
 808 static int fat_get_short_entry(struct inode *dir, loff_t *pos,
 809                                struct buffer_head **bh,
 810                                struct msdos_dir_entry **de)
 811 {
 812         while (fat_get_entry(dir, pos, bh, de) >= 0) {
 813                 /* free entry or long name entry or volume label */
 814                 if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
 815                         return 0;
 816         }
 817         return -ENOENT;
 818 }
 819
 820 /*
 821  * The ".." entry can not provide the "struct fat_slot_info" informations
 822  * for inode. So, this function provide the some informations only.
 823  */
 824 int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
 825                          struct msdos_dir_entry **de, loff_t *i_pos)
 826 {
 827         loff_t offset;
 828
 829         offset = 0;
 830         *bh = NULL;
 831         while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
 832                 if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) {
 833                         *i_pos = fat_make_i_pos(dir->i_sb, *bh, *de);
 834                         return 0;
 835                 }
 836         }
 837         return -ENOENT;
 838 }
 839
 840 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
 841
 842 /* See if directory is empty */
 843 int fat_dir_empty(struct inode *dir)
 844 {
 845         struct buffer_head *bh;
 846         struct msdos_dir_entry *de;
 847         loff_t cpos;
 848         int result = 0;
 849
 850         bh = NULL;
 851         cpos = 0;
 852         while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
 853                 if (strncmp(de->name, MSDOS_DOT   , MSDOS_NAME) &&
 854                     strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
 855                         result = -ENOTEMPTY;
 856                         break;
 857                 }
 858         }
 859         brelse(bh);
 860         return result;
 861 }
 862
 863 EXPORT_SYMBOL_GPL(fat_dir_empty);
 864
 865 /*
 866  * fat_subdirs counts the number of sub-directories of dir. It can be run
 867  * on directories being created.
 868  */
 869 int fat_subdirs(struct inode *dir)
 870 {
 871         struct buffer_head *bh;
 872         struct msdos_dir_entry *de;
 873         loff_t cpos;
 874         int count = 0;
 875
 876         bh = NULL;
 877         cpos = 0;
 878         while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
 879                 if (de->attr & ATTR_DIR)
 880                         count++;
 881         }
 882         brelse(bh);
 883         return count;
 884 }
 885
 886 /*
 887  * Scans a directory for a given file (name points to its formatted name).
 888  * Returns an error code or zero.
 889  */
 890 int fat_scan(struct inode *dir, const unsigned char *name,
 891              struct fat_slot_info *sinfo)
 892 {
 893         struct super_block *sb = dir->i_sb;
 894
 895         sinfo->slot_off = 0;
 896         sinfo->bh = NULL;
 897         while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
 898                                    &sinfo->de) >= 0) {
 899                 if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
 900                         sinfo->slot_off -= sizeof(*sinfo->de);
 901                         sinfo->nr_slots = 1;
 902                         sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
 903                         return 0;
 904                 }
 905         }
 906         return -ENOENT;
 907 }
 908
 909 EXPORT_SYMBOL_GPL(fat_scan);
 910
 911 static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
 912 {
 913         struct super_block *sb = dir->i_sb;
 914         struct buffer_head *bh;
 915         struct msdos_dir_entry *de, *endp;
 916         int err = 0, orig_slots;
 917
 918         while (nr_slots) {
 919                 bh = NULL;
 920                 if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
 921                         err = -EIO;
 922                         break;
 923                 }
 924
 925                 orig_slots = nr_slots;
 926                 endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
 927                 while (nr_slots && de < endp) {
 928                         de->name[0] = DELETED_FLAG;
 929                         de++;
 930                         nr_slots--;
 931                 }
 932                 mark_buffer_dirty(bh);
 933                 if (IS_DIRSYNC(dir))
 934                         err = sync_dirty_buffer(bh);
 935                 brelse(bh);
 936                 if (err)
 937                         break;
 938
 939                 /* pos is *next* de's position, so this does `- sizeof(de)' */
 940                 pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
 941         }
 942
 943         return err;
 944 }
 945
 946 int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
 947 {
 948         struct msdos_dir_entry *de;
 949         struct buffer_head *bh;
 950         int err = 0, nr_slots;
 951
 952         /*
 953          * First stage: Remove the shortname. By this, the directory
 954          * entry is removed.
 955          */
 956         nr_slots = sinfo->nr_slots;
 957         de = sinfo->de;
 958         sinfo->de = NULL;
 959         bh = sinfo->bh;
 960         sinfo->bh = NULL;
 961         while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
 962                 de->name[0] = DELETED_FLAG;
 963                 de--;
 964                 nr_slots--;
 965         }
 966         mark_buffer_dirty(bh);
 967         if (IS_DIRSYNC(dir))
 968                 err = sync_dirty_buffer(bh);
 969         brelse(bh);
 970         if (err)
 971                 return err;
 972         dir->i_version++;
 973
 974         if (nr_slots) {
 975                 /*
 976                  * Second stage: remove the remaining longname slots.
 977                  * (This directory entry is already removed, and so return
 978                  * the success)
 979                  */
 980                 err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
 981                 if (err) {
 982                         printk(KERN_WARNING
 983                                "FAT: Couldn't remove the long name slots\n");
 984                 }
 985         }
 986
 987         dir->i_mtime = dir->i_atime = CURRENT_TIME_SEC;
 988         if (IS_DIRSYNC(dir))
 989                 (void)fat_sync_inode(dir);
 990         else
 991                 mark_inode_dirty(dir);
 992
 993         return 0;
 994 }
 995
 996 EXPORT_SYMBOL_GPL(fat_remove_entries);
 997
 998 static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
 999                               struct buffer_head **bhs, int nr_bhs)
1000 {
1001         struct super_block *sb = dir->i_sb;
1002         sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
1003         int err, i, n;
1004
1005         /* Zeroing the unused blocks on this cluster */
1006         blknr += nr_used;
1007         n = nr_used;
1008         while (blknr < last_blknr) {
1009                 bhs[n] = sb_getblk(sb, blknr);
1010                 if (!bhs[n]) {
1011                         err = -ENOMEM;
1012                         goto error;
1013                 }
1014                 memset(bhs[n]->b_data, 0, sb->s_blocksize);
1015                 set_buffer_uptodate(bhs[n]);
1016                 mark_buffer_dirty(bhs[n]);
1017
1018                 n++;
1019                 blknr++;
1020                 if (n == nr_bhs) {
1021                         if (IS_DIRSYNC(dir)) {
1022                                 err = fat_sync_bhs(bhs, n);
1023                                 if (err)
1024                                         goto error;
1025                         }
1026                         for (i = 0; i < n; i++)
1027                                 brelse(bhs[i]);
1028                         n = 0;
1029                 }
1030         }
1031         if (IS_DIRSYNC(dir)) {
1032                 err = fat_sync_bhs(bhs, n);
1033                 if (err)
1034                         goto error;
1035         }
1036         for (i = 0; i < n; i++)
1037                 brelse(bhs[i]);
1038
1039         return 0;
1040
1041 error:
1042         for (i = 0; i < n; i++)
1043                 bforget(bhs[i]);
1044         return err;
1045 }
1046
1047 int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
1048 {
1049         struct super_block *sb = dir->i_sb;
1050         struct msdos_sb_info *sbi = MSDOS_SB(sb);
1051         struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1052         struct msdos_dir_entry *de;
1053         sector_t blknr;
1054         __le16 date, time;
1055         int err, cluster;
1056
1057         err = fat_alloc_clusters(dir, &cluster, 1);
1058         if (err)
1059                 goto error;
1060
1061         blknr = fat_clus_to_blknr(sbi, cluster);
1062         bhs[0] = sb_getblk(sb, blknr);
1063         if (!bhs[0]) {
1064                 err = -ENOMEM;
1065                 goto error_free;
1066         }
1067
1068         fat_date_unix2dos(ts->tv_sec, &time, &date);
1069
1070         de = (struct msdos_dir_entry *)bhs[0]->b_data;
1071         /* filling the new directory slots ("." and ".." entries) */
1072         memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
1073         memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
1074         de->attr = de[1].attr = ATTR_DIR;
1075         de[0].lcase = de[1].lcase = 0;
1076         de[0].time = de[1].time = time;
1077         de[0].date = de[1].date = date;
1078         de[0].ctime_cs = de[1].ctime_cs = 0;
1079         if (sbi->options.isvfat) {
1080                 /* extra timestamps */
1081                 de[0].ctime = de[1].ctime = time;
1082                 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
1083         } else {
1084                 de[0].ctime = de[1].ctime = 0;
1085                 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
1086         }
1087         de[0].start = cpu_to_le16(cluster);
1088         de[0].starthi = cpu_to_le16(cluster >> 16);
1089         de[1].start = cpu_to_le16(MSDOS_I(dir)->i_logstart);
1090         de[1].starthi = cpu_to_le16(MSDOS_I(dir)->i_logstart >> 16);
1091         de[0].size = de[1].size = 0;
1092         memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
1093         set_buffer_uptodate(bhs[0]);
1094         mark_buffer_dirty(bhs[0]);
1095
1096         err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
1097         if (err)
1098                 goto error_free;
1099
1100         return cluster;
1101
1102 error_free:
1103         fat_free_clusters(dir, cluster);
1104 error:
1105         return err;
1106 }
1107
1108 EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
1109
1110 static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
1111                                int *nr_cluster, struct msdos_dir_entry **de,
1112                                struct buffer_head **bh, loff_t *i_pos)
1113 {
1114         struct super_block *sb = dir->i_sb;
1115         struct msdos_sb_info *sbi = MSDOS_SB(sb);
1116         struct buffer_head *bhs[MAX_BUF_PER_PAGE];
1117         sector_t blknr, start_blknr, last_blknr;
1118         unsigned long size, copy;
1119         int err, i, n, offset, cluster[2];
1120
1121         /*
1122          * The minimum cluster size is 512bytes, and maximum entry
1123          * size is 32*slots (672bytes).  So, iff the cluster size is
1124          * 512bytes, we may need two clusters.
1125          */
1126         size = nr_slots * sizeof(struct msdos_dir_entry);
1127         *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
1128         BUG_ON(*nr_cluster > 2);
1129
1130         err = fat_alloc_clusters(dir, cluster, *nr_cluster);
1131         if (err)
1132                 goto error;
1133
1134         /*
1135          * First stage: Fill the directory entry.  NOTE: This cluster
1136          * is not referenced from any inode yet, so updates order is
1137          * not important.
1138          */
1139         i = n = copy = 0;
1140         do {
1141                 start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
1142                 last_blknr = start_blknr + sbi->sec_per_clus;
1143                 while (blknr < last_blknr) {
1144                         bhs[n] = sb_getblk(sb, blknr);
1145                         if (!bhs[n]) {
1146                                 err = -ENOMEM;
1147                                 goto error_nomem;
1148                         }
1149
1150                         /* fill the directory entry */
1151                         copy = min(size, sb->s_blocksize);
1152                         memcpy(bhs[n]->b_data, slots, copy);
1153                         slots += copy;
1154                         size -= copy;
1155                         set_buffer_uptodate(bhs[n]);
1156                         mark_buffer_dirty(bhs[n]);
1157                         if (!size)
1158                                 break;
1159                         n++;
1160                         blknr++;
1161                 }
1162         } while (++i < *nr_cluster);
1163
1164         memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
1165         offset = copy - sizeof(struct msdos_dir_entry);
1166         get_bh(bhs[n]);
1167         *bh = bhs[n];
1168         *de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
1169         *i_pos = fat_make_i_pos(sb, *bh, *de);
1170
1171         /* Second stage: clear the rest of cluster, and write outs */
1172         err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
1173         if (err)
1174                 goto error_free;
1175
1176         return cluster[0];
1177
1178 error_free:
1179         brelse(*bh);
1180         *bh = NULL;
1181         n = 0;
1182 error_nomem:
1183         for (i = 0; i < n; i++)
1184                 bforget(bhs[i]);
1185         fat_free_clusters(dir, cluster[0]);
1186 error:
1187         return err;
1188 }
1189
1190 int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
1191                     struct fat_slot_info *sinfo)
1192 {
1193         struct super_block *sb = dir->i_sb;
1194         struct msdos_sb_info *sbi = MSDOS_SB(sb);
1195         struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
1196         struct msdos_dir_entry *de;
1197         int err, free_slots, i, nr_bhs;
1198         loff_t pos, i_pos;
1199
1200         sinfo->nr_slots = nr_slots;
1201
1202         /* First stage: search free direcotry entries */
1203         free_slots = nr_bhs = 0;
1204         bh = prev = NULL;
1205         pos = 0;
1206         err = -ENOSPC;
1207         while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
1208                 /* check the maximum size of directory */
1209                 if (pos >= FAT_MAX_DIR_SIZE)
1210                         goto error;
1211
1212                 if (IS_FREE(de->name)) {
1213                         if (prev != bh) {
1214                                 get_bh(bh);
1215                                 bhs[nr_bhs] = prev = bh;
1216                                 nr_bhs++;
1217                         }
1218                         free_slots++;
1219                         if (free_slots == nr_slots)
1220                                 goto found;
1221                 } else {
1222                         for (i = 0; i < nr_bhs; i++)
1223                                 brelse(bhs[i]);
1224                         prev = NULL;
1225                         free_slots = nr_bhs = 0;
1226                 }
1227         }
1228         if (dir->i_ino == MSDOS_ROOT_INO) {
1229                 if (sbi->fat_bits != 32)
1230                         goto error;
1231         } else if (MSDOS_I(dir)->i_start == 0) {
1232                 printk(KERN_ERR "FAT: Corrupted directory (i_pos %lld)\n",
1233                        MSDOS_I(dir)->i_pos);
1234                 err = -EIO;
1235                 goto error;
1236         }
1237
1238 found:
1239         err = 0;
1240         pos -= free_slots * sizeof(*de);
1241         nr_slots -= free_slots;
1242         if (free_slots) {
1243                 /*
1244                  * Second stage: filling the free entries with new entries.
1245                  * NOTE: If this slots has shortname, first, we write
1246                  * the long name slots, then write the short name.
1247                  */
1248                 int size = free_slots * sizeof(*de);
1249                 int offset = pos & (sb->s_blocksize - 1);
1250                 int long_bhs = nr_bhs - (nr_slots == 0);
1251
1252                 /* Fill the long name slots. */
1253                 for (i = 0; i < long_bhs; i++) {
1254                         int copy = min_t(int, sb->s_blocksize - offset, size);
1255                         memcpy(bhs[i]->b_data + offset, slots, copy);
1256                         mark_buffer_dirty(bhs[i]);
1257                         offset = 0;
1258                         slots += copy;
1259                         size -= copy;
1260                 }
1261                 if (long_bhs && IS_DIRSYNC(dir))
1262                         err = fat_sync_bhs(bhs, long_bhs);
1263                 if (!err && i < nr_bhs) {
1264                         /* Fill the short name slot. */
1265                         int copy = min_t(int, sb->s_blocksize - offset, size);
1266                         memcpy(bhs[i]->b_data + offset, slots, copy);
1267                         mark_buffer_dirty(bhs[i]);
1268                         if (IS_DIRSYNC(dir))
1269                                 err = sync_dirty_buffer(bhs[i]);
1270                 }
1271                 for (i = 0; i < nr_bhs; i++)
1272                         brelse(bhs[i]);
1273                 if (err)
1274                         goto error_remove;
1275         }
1276
1277         if (nr_slots) {
1278                 int cluster, nr_cluster;
1279
1280                 /*
1281                  * Third stage: allocate the cluster for new entries.
1282                  * And initialize the cluster with new entries, then
1283                  * add the cluster to dir.
1284                  */
1285                 cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
1286                                               &de, &bh, &i_pos);
1287                 if (cluster < 0) {
1288                         err = cluster;
1289                         goto error_remove;
1290                 }
1291                 err = fat_chain_add(dir, cluster, nr_cluster);
1292                 if (err) {
1293                         fat_free_clusters(dir, cluster);
1294                         goto error_remove;
1295                 }
1296                 if (dir->i_size & (sbi->cluster_size - 1)) {
1297                         fat_fs_panic(sb, "Odd directory size");
1298                         dir->i_size = (dir->i_size + sbi->cluster_size - 1)
1299                                 & ~((loff_t)sbi->cluster_size - 1);
1300                 }
1301                 dir->i_size += nr_cluster << sbi->cluster_bits;
1302                 MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
1303         }
1304         sinfo->slot_off = pos;
1305         sinfo->de = de;
1306         sinfo->bh = bh;
1307         sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
1308
1309         return 0;
1310
1311 error:
1312         brelse(bh);
1313         for (i = 0; i < nr_bhs; i++)
1314                 brelse(bhs[i]);
1315         return err;
1316
1317 error_remove:
1318         brelse(bh);
1319         if (free_slots)
1320                 __fat_remove_entries(dir, pos, free_slots);
1321         return err;
1322 }
1323
1324 EXPORT_SYMBOL_GPL(fat_add_entries);