1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/fs/fat/dir.c 4 * 5 * directory handling functions for fat-based filesystems 6 * 7 * Written 1992,1993 by Werner Almesberger 8 * 9 * Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu> 10 * 11 * VFAT extensions by Gordon Chaffee <chaffee@plateau.cs.berkeley.edu> 12 * Merged with msdos fs by Henrik Storner <storner@osiris.ping.dk> 13 * Rewritten for constant inumbers. Plugged buffer overrun in readdir(). AV 14 * Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de> 15 */ 16 17 #include <linux/slab.h> 18 #include <linux/compat.h> 19 #include <linux/uaccess.h> 20 #include <linux/iversion.h> 21 #include "fat.h" 22 23 /* 24 * Maximum buffer size of short name. 25 * [(MSDOS_NAME + '.') * max one char + nul] 26 * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul] 27 */ 28 #define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1) 29 /* 30 * Maximum buffer size of unicode chars from slots. 31 * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)] 32 */ 33 #define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1) 34 #define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t)) 35 36 static inline unsigned char fat_tolower(unsigned char c) 37 { 38 return ((c >= 'A') && (c <= 'Z')) ? c+32 : c; 39 } 40 41 static inline loff_t fat_make_i_pos(struct super_block *sb, 42 struct buffer_head *bh, 43 struct msdos_dir_entry *de) 44 { 45 return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits) 46 | (de - (struct msdos_dir_entry *)bh->b_data); 47 } 48 49 static inline void fat_dir_readahead(struct inode *dir, sector_t iblock, 50 sector_t phys) 51 { 52 struct super_block *sb = dir->i_sb; 53 struct msdos_sb_info *sbi = MSDOS_SB(sb); 54 struct buffer_head *bh; 55 int sec; 56 57 /* This is not a first sector of cluster, or sec_per_clus == 1 */ 58 if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1) 59 return; 60 /* root dir of FAT12/FAT16 */ 61 if (!is_fat32(sbi) && (dir->i_ino == MSDOS_ROOT_INO)) 62 return; 63 64 bh = sb_find_get_block(sb, phys); 65 if (bh == NULL || !buffer_uptodate(bh)) { 66 for (sec = 0; sec < sbi->sec_per_clus; sec++) 67 sb_breadahead(sb, phys + sec); 68 } 69 brelse(bh); 70 } 71 72 /* Returns the inode number of the directory entry at offset pos. If bh is 73 non-NULL, it is brelse'd before. Pos is incremented. The buffer header is 74 returned in bh. 75 AV. Most often we do it item-by-item. Makes sense to optimize. 76 AV. OK, there we go: if both bh and de are non-NULL we assume that we just 77 AV. want the next entry (took one explicit de=NULL in vfat/namei.c). 78 AV. It's done in fat_get_entry() (inlined), here the slow case lives. 79 AV. Additionally, when we return -1 (i.e. reached the end of directory) 80 AV. we make bh NULL. 81 */ 82 static int fat__get_entry(struct inode *dir, loff_t *pos, 83 struct buffer_head **bh, struct msdos_dir_entry **de) 84 { 85 struct super_block *sb = dir->i_sb; 86 sector_t phys, iblock; 87 unsigned long mapped_blocks; 88 int err, offset; 89 90 next: 91 brelse(*bh); 92 *bh = NULL; 93 iblock = *pos >> sb->s_blocksize_bits; 94 err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0, false); 95 if (err || !phys) 96 return -1; /* beyond EOF or error */ 97 98 fat_dir_readahead(dir, iblock, phys); 99 100 *bh = sb_bread(sb, phys); 101 if (*bh == NULL) { 102 fat_msg_ratelimit(sb, KERN_ERR, 103 "Directory bread(block %llu) failed", (llu)phys); 104 /* skip this block */ 105 *pos = (iblock + 1) << sb->s_blocksize_bits; 106 goto next; 107 } 108 109 offset = *pos & (sb->s_blocksize - 1); 110 *pos += sizeof(struct msdos_dir_entry); 111 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset); 112 113 return 0; 114 } 115 116 static inline int fat_get_entry(struct inode *dir, loff_t *pos, 117 struct buffer_head **bh, 118 struct msdos_dir_entry **de) 119 { 120 /* Fast stuff first */ 121 if (*bh && *de && 122 (*de - (struct msdos_dir_entry *)(*bh)->b_data) < 123 MSDOS_SB(dir->i_sb)->dir_per_block - 1) { 124 *pos += sizeof(struct msdos_dir_entry); 125 (*de)++; 126 return 0; 127 } 128 return fat__get_entry(dir, pos, bh, de); 129 } 130 131 /* 132 * Convert Unicode 16 to UTF-8, translated Unicode, or ASCII. 133 * If uni_xlate is enabled and we can't get a 1:1 conversion, use a 134 * colon as an escape character since it is normally invalid on the vfat 135 * filesystem. The following four characters are the hexadecimal digits 136 * of Unicode value. This lets us do a full dump and restore of Unicode 137 * filenames. We could get into some trouble with long Unicode names, 138 * but ignore that right now. 139 * Ahem... Stack smashing in ring 0 isn't fun. Fixed. 140 */ 141 static int uni16_to_x8(struct super_block *sb, unsigned char *ascii, 142 const wchar_t *uni, int len, struct nls_table *nls) 143 { 144 int uni_xlate = MSDOS_SB(sb)->options.unicode_xlate; 145 const wchar_t *ip; 146 wchar_t ec; 147 unsigned char *op; 148 int charlen; 149 150 ip = uni; 151 op = ascii; 152 153 while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) { 154 ec = *ip++; 155 charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE); 156 if (charlen > 0) { 157 op += charlen; 158 len -= charlen; 159 } else { 160 if (uni_xlate == 1) { 161 *op++ = ':'; 162 op = hex_byte_pack(op, ec >> 8); 163 op = hex_byte_pack(op, ec); 164 len -= 5; 165 } else { 166 *op++ = '?'; 167 len--; 168 } 169 } 170 } 171 172 if (unlikely(*ip)) { 173 fat_msg(sb, KERN_WARNING, 174 "filename was truncated while converting."); 175 } 176 177 *op = 0; 178 return op - ascii; 179 } 180 181 static inline int fat_uni_to_x8(struct super_block *sb, const wchar_t *uni, 182 unsigned char *buf, int size) 183 { 184 struct msdos_sb_info *sbi = MSDOS_SB(sb); 185 if (sbi->options.utf8) 186 return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS, 187 UTF16_HOST_ENDIAN, buf, size); 188 else 189 return uni16_to_x8(sb, buf, uni, size, sbi->nls_io); 190 } 191 192 static inline int 193 fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni) 194 { 195 int charlen; 196 197 charlen = t->char2uni(c, clen, uni); 198 if (charlen < 0) { 199 *uni = 0x003f; /* a question mark */ 200 charlen = 1; 201 } 202 return charlen; 203 } 204 205 static inline int 206 fat_short2lower_uni(struct nls_table *t, unsigned char *c, 207 int clen, wchar_t *uni) 208 { 209 int charlen; 210 wchar_t wc; 211 212 charlen = t->char2uni(c, clen, &wc); 213 if (charlen < 0) { 214 *uni = 0x003f; /* a question mark */ 215 charlen = 1; 216 } else if (charlen <= 1) { 217 unsigned char nc = t->charset2lower[*c]; 218 219 if (!nc) 220 nc = *c; 221 222 charlen = t->char2uni(&nc, 1, uni); 223 if (charlen < 0) { 224 *uni = 0x003f; /* a question mark */ 225 charlen = 1; 226 } 227 } else 228 *uni = wc; 229 230 return charlen; 231 } 232 233 static inline int 234 fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size, 235 wchar_t *uni_buf, unsigned short opt, int lower) 236 { 237 int len = 0; 238 239 if (opt & VFAT_SFN_DISPLAY_LOWER) 240 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf); 241 else if (opt & VFAT_SFN_DISPLAY_WIN95) 242 len = fat_short2uni(nls, buf, buf_size, uni_buf); 243 else if (opt & VFAT_SFN_DISPLAY_WINNT) { 244 if (lower) 245 len = fat_short2lower_uni(nls, buf, buf_size, uni_buf); 246 else 247 len = fat_short2uni(nls, buf, buf_size, uni_buf); 248 } else 249 len = fat_short2uni(nls, buf, buf_size, uni_buf); 250 251 return len; 252 } 253 254 static inline int fat_name_match(struct msdos_sb_info *sbi, 255 const unsigned char *a, int a_len, 256 const unsigned char *b, int b_len) 257 { 258 if (a_len != b_len) 259 return 0; 260 261 if (sbi->options.name_check != 's') 262 return !nls_strnicmp(sbi->nls_io, a, b, a_len); 263 else 264 return !memcmp(a, b, a_len); 265 } 266 267 enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, }; 268 269 /** 270 * fat_parse_long - Parse extended directory entry. 271 * 272 * This function returns zero on success, negative value on error, or one of 273 * the following: 274 * 275 * %PARSE_INVALID - Directory entry is invalid. 276 * %PARSE_NOT_LONGNAME - Directory entry does not contain longname. 277 * %PARSE_EOF - Directory has no more entries. 278 */ 279 static int fat_parse_long(struct inode *dir, loff_t *pos, 280 struct buffer_head **bh, struct msdos_dir_entry **de, 281 wchar_t **unicode, unsigned char *nr_slots) 282 { 283 struct msdos_dir_slot *ds; 284 unsigned char id, slot, slots, alias_checksum; 285 286 if (!*unicode) { 287 *unicode = __getname(); 288 if (!*unicode) { 289 brelse(*bh); 290 return -ENOMEM; 291 } 292 } 293 parse_long: 294 ds = (struct msdos_dir_slot *)*de; 295 id = ds->id; 296 if (!(id & 0x40)) 297 return PARSE_INVALID; 298 slots = id & ~0x40; 299 if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */ 300 return PARSE_INVALID; 301 *nr_slots = slots; 302 alias_checksum = ds->alias_checksum; 303 304 slot = slots; 305 while (1) { 306 int offset; 307 308 slot--; 309 offset = slot * 13; 310 fat16_towchar(*unicode + offset, ds->name0_4, 5); 311 fat16_towchar(*unicode + offset + 5, ds->name5_10, 6); 312 fat16_towchar(*unicode + offset + 11, ds->name11_12, 2); 313 314 if (ds->id & 0x40) 315 (*unicode)[offset + 13] = 0; 316 if (fat_get_entry(dir, pos, bh, de) < 0) 317 return PARSE_EOF; 318 if (slot == 0) 319 break; 320 ds = (struct msdos_dir_slot *)*de; 321 if (ds->attr != ATTR_EXT) 322 return PARSE_NOT_LONGNAME; 323 if ((ds->id & ~0x40) != slot) 324 goto parse_long; 325 if (ds->alias_checksum != alias_checksum) 326 goto parse_long; 327 } 328 if ((*de)->name[0] == DELETED_FLAG) 329 return PARSE_INVALID; 330 if ((*de)->attr == ATTR_EXT) 331 goto parse_long; 332 if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME)) 333 return PARSE_INVALID; 334 if (fat_checksum((*de)->name) != alias_checksum) 335 *nr_slots = 0; 336 337 return 0; 338 } 339 340 /** 341 * fat_parse_short - Parse MS-DOS (short) directory entry. 342 * @sb: superblock 343 * @de: directory entry to parse 344 * @name: FAT_MAX_SHORT_SIZE array in which to place extracted name 345 * @dot_hidden: Nonzero == prepend '.' to names with ATTR_HIDDEN 346 * 347 * Returns the number of characters extracted into 'name'. 348 */ 349 static int fat_parse_short(struct super_block *sb, 350 const struct msdos_dir_entry *de, 351 unsigned char *name, int dot_hidden) 352 { 353 const struct msdos_sb_info *sbi = MSDOS_SB(sb); 354 int isvfat = sbi->options.isvfat; 355 int nocase = sbi->options.nocase; 356 unsigned short opt_shortname = sbi->options.shortname; 357 struct nls_table *nls_disk = sbi->nls_disk; 358 wchar_t uni_name[14]; 359 unsigned char c, work[MSDOS_NAME]; 360 unsigned char *ptname = name; 361 int chi, chl, i, j, k; 362 int dotoffset = 0; 363 int name_len = 0, uni_len = 0; 364 365 if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) { 366 *ptname++ = '.'; 367 dotoffset = 1; 368 } 369 370 memcpy(work, de->name, sizeof(work)); 371 /* For an explanation of the special treatment of 0x05 in 372 * filenames, see msdos_format_name in namei_msdos.c 373 */ 374 if (work[0] == 0x05) 375 work[0] = 0xE5; 376 377 /* Filename */ 378 for (i = 0, j = 0; i < 8;) { 379 c = work[i]; 380 if (!c) 381 break; 382 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i, 383 &uni_name[j++], opt_shortname, 384 de->lcase & CASE_LOWER_BASE); 385 if (chl <= 1) { 386 if (!isvfat) 387 ptname[i] = nocase ? c : fat_tolower(c); 388 i++; 389 if (c != ' ') { 390 name_len = i; 391 uni_len = j; 392 } 393 } else { 394 uni_len = j; 395 if (isvfat) 396 i += min(chl, 8-i); 397 else { 398 for (chi = 0; chi < chl && i < 8; chi++, i++) 399 ptname[i] = work[i]; 400 } 401 if (chl) 402 name_len = i; 403 } 404 } 405 406 i = name_len; 407 j = uni_len; 408 fat_short2uni(nls_disk, ".", 1, &uni_name[j++]); 409 if (!isvfat) 410 ptname[i] = '.'; 411 i++; 412 413 /* Extension */ 414 for (k = 8; k < MSDOS_NAME;) { 415 c = work[k]; 416 if (!c) 417 break; 418 chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k, 419 &uni_name[j++], opt_shortname, 420 de->lcase & CASE_LOWER_EXT); 421 if (chl <= 1) { 422 k++; 423 if (!isvfat) 424 ptname[i] = nocase ? c : fat_tolower(c); 425 i++; 426 if (c != ' ') { 427 name_len = i; 428 uni_len = j; 429 } 430 } else { 431 uni_len = j; 432 if (isvfat) { 433 int offset = min(chl, MSDOS_NAME-k); 434 k += offset; 435 i += offset; 436 } else { 437 for (chi = 0; chi < chl && k < MSDOS_NAME; 438 chi++, i++, k++) { 439 ptname[i] = work[k]; 440 } 441 } 442 if (chl) 443 name_len = i; 444 } 445 } 446 447 if (name_len > 0) { 448 name_len += dotoffset; 449 450 if (sbi->options.isvfat) { 451 uni_name[uni_len] = 0x0000; 452 name_len = fat_uni_to_x8(sb, uni_name, name, 453 FAT_MAX_SHORT_SIZE); 454 } 455 } 456 457 return name_len; 458 } 459 460 /* 461 * Return values: negative -> error/not found, 0 -> found. 462 */ 463 int fat_search_long(struct inode *inode, const unsigned char *name, 464 int name_len, struct fat_slot_info *sinfo) 465 { 466 struct super_block *sb = inode->i_sb; 467 struct msdos_sb_info *sbi = MSDOS_SB(sb); 468 struct buffer_head *bh = NULL; 469 struct msdos_dir_entry *de; 470 unsigned char nr_slots; 471 wchar_t *unicode = NULL; 472 unsigned char bufname[FAT_MAX_SHORT_SIZE]; 473 loff_t cpos = 0; 474 int err, len; 475 476 err = -ENOENT; 477 while (1) { 478 if (fat_get_entry(inode, &cpos, &bh, &de) == -1) 479 goto end_of_dir; 480 parse_record: 481 nr_slots = 0; 482 if (de->name[0] == DELETED_FLAG) 483 continue; 484 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) 485 continue; 486 if (de->attr != ATTR_EXT && IS_FREE(de->name)) 487 continue; 488 if (de->attr == ATTR_EXT) { 489 int status = fat_parse_long(inode, &cpos, &bh, &de, 490 &unicode, &nr_slots); 491 if (status < 0) { 492 err = status; 493 goto end_of_dir; 494 } else if (status == PARSE_INVALID) 495 continue; 496 else if (status == PARSE_NOT_LONGNAME) 497 goto parse_record; 498 else if (status == PARSE_EOF) 499 goto end_of_dir; 500 } 501 502 /* Never prepend '.' to hidden files here. 503 * That is done only for msdos mounts (and only when 504 * 'dotsOK=yes'); if we are executing here, it is in the 505 * context of a vfat mount. 506 */ 507 len = fat_parse_short(sb, de, bufname, 0); 508 if (len == 0) 509 continue; 510 511 /* Compare shortname */ 512 if (fat_name_match(sbi, name, name_len, bufname, len)) 513 goto found; 514 515 if (nr_slots) { 516 void *longname = unicode + FAT_MAX_UNI_CHARS; 517 int size = PATH_MAX - FAT_MAX_UNI_SIZE; 518 519 /* Compare longname */ 520 len = fat_uni_to_x8(sb, unicode, longname, size); 521 if (fat_name_match(sbi, name, name_len, longname, len)) 522 goto found; 523 } 524 } 525 526 found: 527 nr_slots++; /* include the de */ 528 sinfo->slot_off = cpos - nr_slots * sizeof(*de); 529 sinfo->nr_slots = nr_slots; 530 sinfo->de = de; 531 sinfo->bh = bh; 532 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 533 err = 0; 534 end_of_dir: 535 if (unicode) 536 __putname(unicode); 537 538 return err; 539 } 540 EXPORT_SYMBOL_GPL(fat_search_long); 541 542 struct fat_ioctl_filldir_callback { 543 struct dir_context ctx; 544 void __user *dirent; 545 int result; 546 /* for dir ioctl */ 547 const char *longname; 548 int long_len; 549 const char *shortname; 550 int short_len; 551 }; 552 553 static int __fat_readdir(struct inode *inode, struct file *file, 554 struct dir_context *ctx, int short_only, 555 struct fat_ioctl_filldir_callback *both) 556 { 557 struct super_block *sb = inode->i_sb; 558 struct msdos_sb_info *sbi = MSDOS_SB(sb); 559 struct buffer_head *bh; 560 struct msdos_dir_entry *de; 561 unsigned char nr_slots; 562 wchar_t *unicode = NULL; 563 unsigned char bufname[FAT_MAX_SHORT_SIZE]; 564 int isvfat = sbi->options.isvfat; 565 const char *fill_name = NULL; 566 int fake_offset = 0; 567 loff_t cpos; 568 int short_len = 0, fill_len = 0; 569 int ret = 0; 570 571 mutex_lock(&sbi->s_lock); 572 573 cpos = ctx->pos; 574 /* Fake . and .. for the root directory. */ 575 if (inode->i_ino == MSDOS_ROOT_INO) { 576 if (!dir_emit_dots(file, ctx)) 577 goto out; 578 if (ctx->pos == 2) { 579 fake_offset = 1; 580 cpos = 0; 581 } 582 } 583 if (cpos & (sizeof(struct msdos_dir_entry) - 1)) { 584 ret = -ENOENT; 585 goto out; 586 } 587 588 bh = NULL; 589 get_new: 590 if (fat_get_entry(inode, &cpos, &bh, &de) == -1) 591 goto end_of_dir; 592 parse_record: 593 nr_slots = 0; 594 /* 595 * Check for long filename entry, but if short_only, we don't 596 * need to parse long filename. 597 */ 598 if (isvfat && !short_only) { 599 if (de->name[0] == DELETED_FLAG) 600 goto record_end; 601 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) 602 goto record_end; 603 if (de->attr != ATTR_EXT && IS_FREE(de->name)) 604 goto record_end; 605 } else { 606 if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name)) 607 goto record_end; 608 } 609 610 if (isvfat && de->attr == ATTR_EXT) { 611 int status = fat_parse_long(inode, &cpos, &bh, &de, 612 &unicode, &nr_slots); 613 if (status < 0) { 614 bh = NULL; 615 ret = status; 616 goto end_of_dir; 617 } else if (status == PARSE_INVALID) 618 goto record_end; 619 else if (status == PARSE_NOT_LONGNAME) 620 goto parse_record; 621 else if (status == PARSE_EOF) 622 goto end_of_dir; 623 624 if (nr_slots) { 625 void *longname = unicode + FAT_MAX_UNI_CHARS; 626 int size = PATH_MAX - FAT_MAX_UNI_SIZE; 627 int len = fat_uni_to_x8(sb, unicode, longname, size); 628 629 fill_name = longname; 630 fill_len = len; 631 /* !both && !short_only, so we don't need shortname. */ 632 if (!both) 633 goto start_filldir; 634 635 short_len = fat_parse_short(sb, de, bufname, 636 sbi->options.dotsOK); 637 if (short_len == 0) 638 goto record_end; 639 /* hack for fat_ioctl_filldir() */ 640 both->longname = fill_name; 641 both->long_len = fill_len; 642 both->shortname = bufname; 643 both->short_len = short_len; 644 fill_name = NULL; 645 fill_len = 0; 646 goto start_filldir; 647 } 648 } 649 650 short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK); 651 if (short_len == 0) 652 goto record_end; 653 654 fill_name = bufname; 655 fill_len = short_len; 656 657 start_filldir: 658 ctx->pos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry); 659 if (fake_offset && ctx->pos < 2) 660 ctx->pos = 2; 661 662 if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME)) { 663 if (!dir_emit_dot(file, ctx)) 664 goto fill_failed; 665 } else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { 666 if (!dir_emit_dotdot(file, ctx)) 667 goto fill_failed; 668 } else { 669 unsigned long inum; 670 loff_t i_pos = fat_make_i_pos(sb, bh, de); 671 struct inode *tmp = fat_iget(sb, i_pos); 672 if (tmp) { 673 inum = tmp->i_ino; 674 iput(tmp); 675 } else 676 inum = iunique(sb, MSDOS_ROOT_INO); 677 if (!dir_emit(ctx, fill_name, fill_len, inum, 678 (de->attr & ATTR_DIR) ? DT_DIR : DT_REG)) 679 goto fill_failed; 680 } 681 682 record_end: 683 fake_offset = 0; 684 ctx->pos = cpos; 685 goto get_new; 686 687 end_of_dir: 688 if (fake_offset && cpos < 2) 689 ctx->pos = 2; 690 else 691 ctx->pos = cpos; 692 fill_failed: 693 brelse(bh); 694 if (unicode) 695 __putname(unicode); 696 out: 697 mutex_unlock(&sbi->s_lock); 698 699 return ret; 700 } 701 702 static int fat_readdir(struct file *file, struct dir_context *ctx) 703 { 704 return __fat_readdir(file_inode(file), file, ctx, 0, NULL); 705 } 706 707 #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \ 708 static int func(struct dir_context *ctx, const char *name, int name_len, \ 709 loff_t offset, u64 ino, unsigned int d_type) \ 710 { \ 711 struct fat_ioctl_filldir_callback *buf = \ 712 container_of(ctx, struct fat_ioctl_filldir_callback, ctx); \ 713 struct dirent_type __user *d1 = buf->dirent; \ 714 struct dirent_type __user *d2 = d1 + 1; \ 715 \ 716 if (buf->result) \ 717 return -EINVAL; \ 718 buf->result++; \ 719 \ 720 if (name != NULL) { \ 721 /* dirent has only short name */ \ 722 if (name_len >= sizeof(d1->d_name)) \ 723 name_len = sizeof(d1->d_name) - 1; \ 724 \ 725 if (put_user(0, d2->d_name) || \ 726 put_user(0, &d2->d_reclen) || \ 727 copy_to_user(d1->d_name, name, name_len) || \ 728 put_user(0, d1->d_name + name_len) || \ 729 put_user(name_len, &d1->d_reclen)) \ 730 goto efault; \ 731 } else { \ 732 /* dirent has short and long name */ \ 733 const char *longname = buf->longname; \ 734 int long_len = buf->long_len; \ 735 const char *shortname = buf->shortname; \ 736 int short_len = buf->short_len; \ 737 \ 738 if (long_len >= sizeof(d1->d_name)) \ 739 long_len = sizeof(d1->d_name) - 1; \ 740 if (short_len >= sizeof(d1->d_name)) \ 741 short_len = sizeof(d1->d_name) - 1; \ 742 \ 743 if (copy_to_user(d2->d_name, longname, long_len) || \ 744 put_user(0, d2->d_name + long_len) || \ 745 put_user(long_len, &d2->d_reclen) || \ 746 put_user(ino, &d2->d_ino) || \ 747 put_user(offset, &d2->d_off) || \ 748 copy_to_user(d1->d_name, shortname, short_len) || \ 749 put_user(0, d1->d_name + short_len) || \ 750 put_user(short_len, &d1->d_reclen)) \ 751 goto efault; \ 752 } \ 753 return 0; \ 754 efault: \ 755 buf->result = -EFAULT; \ 756 return -EFAULT; \ 757 } 758 759 FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent) 760 761 static int fat_ioctl_readdir(struct inode *inode, struct file *file, 762 void __user *dirent, filldir_t filldir, 763 int short_only, int both) 764 { 765 struct fat_ioctl_filldir_callback buf = { 766 .ctx.actor = filldir, 767 .dirent = dirent 768 }; 769 int ret; 770 771 buf.dirent = dirent; 772 buf.result = 0; 773 inode_lock_shared(inode); 774 buf.ctx.pos = file->f_pos; 775 ret = -ENOENT; 776 if (!IS_DEADDIR(inode)) { 777 ret = __fat_readdir(inode, file, &buf.ctx, 778 short_only, both ? &buf : NULL); 779 file->f_pos = buf.ctx.pos; 780 } 781 inode_unlock_shared(inode); 782 if (ret >= 0) 783 ret = buf.result; 784 return ret; 785 } 786 787 static long fat_dir_ioctl(struct file *filp, unsigned int cmd, 788 unsigned long arg) 789 { 790 struct inode *inode = file_inode(filp); 791 struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg; 792 int short_only, both; 793 794 switch (cmd) { 795 case VFAT_IOCTL_READDIR_SHORT: 796 short_only = 1; 797 both = 0; 798 break; 799 case VFAT_IOCTL_READDIR_BOTH: 800 short_only = 0; 801 both = 1; 802 break; 803 default: 804 return fat_generic_ioctl(filp, cmd, arg); 805 } 806 807 /* 808 * Yes, we don't need this put_user() absolutely. However old 809 * code didn't return the right value. So, app use this value, 810 * in order to check whether it is EOF. 811 */ 812 if (put_user(0, &d1->d_reclen)) 813 return -EFAULT; 814 815 return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir, 816 short_only, both); 817 } 818 819 #ifdef CONFIG_COMPAT 820 #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2]) 821 #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2]) 822 823 FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent) 824 825 static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd, 826 unsigned long arg) 827 { 828 struct inode *inode = file_inode(filp); 829 struct compat_dirent __user *d1 = compat_ptr(arg); 830 int short_only, both; 831 832 switch (cmd) { 833 case VFAT_IOCTL_READDIR_SHORT32: 834 short_only = 1; 835 both = 0; 836 break; 837 case VFAT_IOCTL_READDIR_BOTH32: 838 short_only = 0; 839 both = 1; 840 break; 841 default: 842 return fat_generic_ioctl(filp, cmd, (unsigned long)arg); 843 } 844 845 /* 846 * Yes, we don't need this put_user() absolutely. However old 847 * code didn't return the right value. So, app use this value, 848 * in order to check whether it is EOF. 849 */ 850 if (put_user(0, &d1->d_reclen)) 851 return -EFAULT; 852 853 return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir, 854 short_only, both); 855 } 856 #endif /* CONFIG_COMPAT */ 857 858 const struct file_operations fat_dir_operations = { 859 .llseek = generic_file_llseek, 860 .read = generic_read_dir, 861 .iterate_shared = fat_readdir, 862 .unlocked_ioctl = fat_dir_ioctl, 863 #ifdef CONFIG_COMPAT 864 .compat_ioctl = fat_compat_dir_ioctl, 865 #endif 866 .fsync = fat_file_fsync, 867 }; 868 869 static int fat_get_short_entry(struct inode *dir, loff_t *pos, 870 struct buffer_head **bh, 871 struct msdos_dir_entry **de) 872 { 873 while (fat_get_entry(dir, pos, bh, de) >= 0) { 874 /* free entry or long name entry or volume label */ 875 if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME)) 876 return 0; 877 } 878 return -ENOENT; 879 } 880 881 /* 882 * The ".." entry can not provide the "struct fat_slot_info" information 883 * for inode, nor a usable i_pos. So, this function provides some information 884 * only. 885 * 886 * Since this function walks through the on-disk inodes within a directory, 887 * callers are responsible for taking any locks necessary to prevent the 888 * directory from changing. 889 */ 890 int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 891 struct msdos_dir_entry **de) 892 { 893 loff_t offset = 0; 894 895 *de = NULL; 896 while (fat_get_short_entry(dir, &offset, bh, de) >= 0) { 897 if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) 898 return 0; 899 } 900 return -ENOENT; 901 } 902 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry); 903 904 /* See if directory is empty */ 905 int fat_dir_empty(struct inode *dir) 906 { 907 struct buffer_head *bh; 908 struct msdos_dir_entry *de; 909 loff_t cpos; 910 int result = 0; 911 912 bh = NULL; 913 cpos = 0; 914 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { 915 if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) && 916 strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { 917 result = -ENOTEMPTY; 918 break; 919 } 920 } 921 brelse(bh); 922 return result; 923 } 924 EXPORT_SYMBOL_GPL(fat_dir_empty); 925 926 /* 927 * fat_subdirs counts the number of sub-directories of dir. It can be run 928 * on directories being created. 929 */ 930 int fat_subdirs(struct inode *dir) 931 { 932 struct buffer_head *bh; 933 struct msdos_dir_entry *de; 934 loff_t cpos; 935 int count = 0; 936 937 bh = NULL; 938 cpos = 0; 939 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { 940 if (de->attr & ATTR_DIR) 941 count++; 942 } 943 brelse(bh); 944 return count; 945 } 946 947 /* 948 * Scans a directory for a given file (name points to its formatted name). 949 * Returns an error code or zero. 950 */ 951 int fat_scan(struct inode *dir, const unsigned char *name, 952 struct fat_slot_info *sinfo) 953 { 954 struct super_block *sb = dir->i_sb; 955 956 sinfo->slot_off = 0; 957 sinfo->bh = NULL; 958 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh, 959 &sinfo->de) >= 0) { 960 if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) { 961 sinfo->slot_off -= sizeof(*sinfo->de); 962 sinfo->nr_slots = 1; 963 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 964 return 0; 965 } 966 } 967 return -ENOENT; 968 } 969 EXPORT_SYMBOL_GPL(fat_scan); 970 971 /* 972 * Scans a directory for a given logstart. 973 * Returns an error code or zero. 974 */ 975 int fat_scan_logstart(struct inode *dir, int i_logstart, 976 struct fat_slot_info *sinfo) 977 { 978 struct super_block *sb = dir->i_sb; 979 980 sinfo->slot_off = 0; 981 sinfo->bh = NULL; 982 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh, 983 &sinfo->de) >= 0) { 984 if (fat_get_start(MSDOS_SB(sb), sinfo->de) == i_logstart) { 985 sinfo->slot_off -= sizeof(*sinfo->de); 986 sinfo->nr_slots = 1; 987 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 988 return 0; 989 } 990 } 991 return -ENOENT; 992 } 993 994 static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots) 995 { 996 struct super_block *sb = dir->i_sb; 997 struct buffer_head *bh; 998 struct msdos_dir_entry *de, *endp; 999 int err = 0, orig_slots; 1000 1001 while (nr_slots) { 1002 bh = NULL; 1003 if (fat_get_entry(dir, &pos, &bh, &de) < 0) { 1004 err = -EIO; 1005 break; 1006 } 1007 1008 orig_slots = nr_slots; 1009 endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize); 1010 while (nr_slots && de < endp) { 1011 de->name[0] = DELETED_FLAG; 1012 de++; 1013 nr_slots--; 1014 } 1015 mark_buffer_dirty_inode(bh, dir); 1016 if (IS_DIRSYNC(dir)) 1017 err = sync_dirty_buffer(bh); 1018 brelse(bh); 1019 if (err) 1020 break; 1021 1022 /* pos is *next* de's position, so this does `- sizeof(de)' */ 1023 pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de); 1024 } 1025 1026 return err; 1027 } 1028 1029 int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo) 1030 { 1031 struct super_block *sb = dir->i_sb; 1032 struct msdos_dir_entry *de; 1033 struct buffer_head *bh; 1034 int err = 0, nr_slots; 1035 1036 /* 1037 * First stage: Remove the shortname. By this, the directory 1038 * entry is removed. 1039 */ 1040 nr_slots = sinfo->nr_slots; 1041 de = sinfo->de; 1042 sinfo->de = NULL; 1043 bh = sinfo->bh; 1044 sinfo->bh = NULL; 1045 while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) { 1046 de->name[0] = DELETED_FLAG; 1047 de--; 1048 nr_slots--; 1049 } 1050 mark_buffer_dirty_inode(bh, dir); 1051 if (IS_DIRSYNC(dir)) 1052 err = sync_dirty_buffer(bh); 1053 brelse(bh); 1054 if (err) 1055 return err; 1056 inode_inc_iversion(dir); 1057 1058 if (nr_slots) { 1059 /* 1060 * Second stage: remove the remaining longname slots. 1061 * (This directory entry is already removed, and so return 1062 * the success) 1063 */ 1064 err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots); 1065 if (err) { 1066 fat_msg(sb, KERN_WARNING, 1067 "Couldn't remove the long name slots"); 1068 } 1069 } 1070 1071 fat_truncate_time(dir, NULL, S_ATIME|S_MTIME); 1072 if (IS_DIRSYNC(dir)) 1073 (void)fat_sync_inode(dir); 1074 else 1075 mark_inode_dirty(dir); 1076 1077 return 0; 1078 } 1079 EXPORT_SYMBOL_GPL(fat_remove_entries); 1080 1081 static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used, 1082 struct buffer_head **bhs, int nr_bhs) 1083 { 1084 struct super_block *sb = dir->i_sb; 1085 sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus; 1086 int err, i, n; 1087 1088 /* Zeroing the unused blocks on this cluster */ 1089 blknr += nr_used; 1090 n = nr_used; 1091 while (blknr < last_blknr) { 1092 bhs[n] = sb_getblk(sb, blknr); 1093 if (!bhs[n]) { 1094 err = -ENOMEM; 1095 goto error; 1096 } 1097 /* Avoid race with userspace read via bdev */ 1098 lock_buffer(bhs[n]); 1099 memset(bhs[n]->b_data, 0, sb->s_blocksize); 1100 set_buffer_uptodate(bhs[n]); 1101 unlock_buffer(bhs[n]); 1102 mark_buffer_dirty_inode(bhs[n], dir); 1103 1104 n++; 1105 blknr++; 1106 if (n == nr_bhs) { 1107 if (IS_DIRSYNC(dir)) { 1108 err = fat_sync_bhs(bhs, n); 1109 if (err) 1110 goto error; 1111 } 1112 for (i = 0; i < n; i++) 1113 brelse(bhs[i]); 1114 n = 0; 1115 } 1116 } 1117 if (IS_DIRSYNC(dir)) { 1118 err = fat_sync_bhs(bhs, n); 1119 if (err) 1120 goto error; 1121 } 1122 for (i = 0; i < n; i++) 1123 brelse(bhs[i]); 1124 1125 return 0; 1126 1127 error: 1128 for (i = 0; i < n; i++) 1129 bforget(bhs[i]); 1130 return err; 1131 } 1132 1133 int fat_alloc_new_dir(struct inode *dir, struct timespec64 *ts) 1134 { 1135 struct super_block *sb = dir->i_sb; 1136 struct msdos_sb_info *sbi = MSDOS_SB(sb); 1137 struct buffer_head *bhs[MAX_BUF_PER_PAGE]; 1138 struct msdos_dir_entry *de; 1139 sector_t blknr; 1140 __le16 date, time; 1141 u8 time_cs; 1142 int err, cluster; 1143 1144 err = fat_alloc_clusters(dir, &cluster, 1); 1145 if (err) 1146 goto error; 1147 1148 blknr = fat_clus_to_blknr(sbi, cluster); 1149 bhs[0] = sb_getblk(sb, blknr); 1150 if (!bhs[0]) { 1151 err = -ENOMEM; 1152 goto error_free; 1153 } 1154 1155 fat_time_unix2fat(sbi, ts, &time, &date, &time_cs); 1156 1157 de = (struct msdos_dir_entry *)bhs[0]->b_data; 1158 /* Avoid race with userspace read via bdev */ 1159 lock_buffer(bhs[0]); 1160 /* filling the new directory slots ("." and ".." entries) */ 1161 memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME); 1162 memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME); 1163 de->attr = de[1].attr = ATTR_DIR; 1164 de[0].lcase = de[1].lcase = 0; 1165 de[0].time = de[1].time = time; 1166 de[0].date = de[1].date = date; 1167 if (sbi->options.isvfat) { 1168 /* extra timestamps */ 1169 de[0].ctime = de[1].ctime = time; 1170 de[0].ctime_cs = de[1].ctime_cs = time_cs; 1171 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date; 1172 } else { 1173 de[0].ctime = de[1].ctime = 0; 1174 de[0].ctime_cs = de[1].ctime_cs = 0; 1175 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0; 1176 } 1177 fat_set_start(&de[0], cluster); 1178 fat_set_start(&de[1], MSDOS_I(dir)->i_logstart); 1179 de[0].size = de[1].size = 0; 1180 memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de)); 1181 set_buffer_uptodate(bhs[0]); 1182 unlock_buffer(bhs[0]); 1183 mark_buffer_dirty_inode(bhs[0], dir); 1184 1185 err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE); 1186 if (err) 1187 goto error_free; 1188 1189 return cluster; 1190 1191 error_free: 1192 fat_free_clusters(dir, cluster); 1193 error: 1194 return err; 1195 } 1196 EXPORT_SYMBOL_GPL(fat_alloc_new_dir); 1197 1198 static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots, 1199 int *nr_cluster, struct msdos_dir_entry **de, 1200 struct buffer_head **bh, loff_t *i_pos) 1201 { 1202 struct super_block *sb = dir->i_sb; 1203 struct msdos_sb_info *sbi = MSDOS_SB(sb); 1204 struct buffer_head *bhs[MAX_BUF_PER_PAGE]; 1205 sector_t blknr, start_blknr, last_blknr; 1206 unsigned long size, copy; 1207 int err, i, n, offset, cluster[2]; 1208 1209 /* 1210 * The minimum cluster size is 512bytes, and maximum entry 1211 * size is 32*slots (672bytes). So, iff the cluster size is 1212 * 512bytes, we may need two clusters. 1213 */ 1214 size = nr_slots * sizeof(struct msdos_dir_entry); 1215 *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits; 1216 BUG_ON(*nr_cluster > 2); 1217 1218 err = fat_alloc_clusters(dir, cluster, *nr_cluster); 1219 if (err) 1220 goto error; 1221 1222 /* 1223 * First stage: Fill the directory entry. NOTE: This cluster 1224 * is not referenced from any inode yet, so updates order is 1225 * not important. 1226 */ 1227 i = n = copy = 0; 1228 do { 1229 start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]); 1230 last_blknr = start_blknr + sbi->sec_per_clus; 1231 while (blknr < last_blknr) { 1232 bhs[n] = sb_getblk(sb, blknr); 1233 if (!bhs[n]) { 1234 err = -ENOMEM; 1235 goto error_nomem; 1236 } 1237 1238 /* fill the directory entry */ 1239 copy = min(size, sb->s_blocksize); 1240 /* Avoid race with userspace read via bdev */ 1241 lock_buffer(bhs[n]); 1242 memcpy(bhs[n]->b_data, slots, copy); 1243 set_buffer_uptodate(bhs[n]); 1244 unlock_buffer(bhs[n]); 1245 mark_buffer_dirty_inode(bhs[n], dir); 1246 slots += copy; 1247 size -= copy; 1248 if (!size) 1249 break; 1250 n++; 1251 blknr++; 1252 } 1253 } while (++i < *nr_cluster); 1254 1255 memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy); 1256 offset = copy - sizeof(struct msdos_dir_entry); 1257 get_bh(bhs[n]); 1258 *bh = bhs[n]; 1259 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset); 1260 *i_pos = fat_make_i_pos(sb, *bh, *de); 1261 1262 /* Second stage: clear the rest of cluster, and write outs */ 1263 err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE); 1264 if (err) 1265 goto error_free; 1266 1267 return cluster[0]; 1268 1269 error_free: 1270 brelse(*bh); 1271 *bh = NULL; 1272 n = 0; 1273 error_nomem: 1274 for (i = 0; i < n; i++) 1275 bforget(bhs[i]); 1276 fat_free_clusters(dir, cluster[0]); 1277 error: 1278 return err; 1279 } 1280 1281 int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 1282 struct fat_slot_info *sinfo) 1283 { 1284 struct super_block *sb = dir->i_sb; 1285 struct msdos_sb_info *sbi = MSDOS_SB(sb); 1286 struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */ 1287 struct msdos_dir_entry *de; 1288 int err, free_slots, i, nr_bhs; 1289 loff_t pos, i_pos; 1290 1291 sinfo->nr_slots = nr_slots; 1292 1293 /* First stage: search free directory entries */ 1294 free_slots = nr_bhs = 0; 1295 bh = prev = NULL; 1296 pos = 0; 1297 err = -ENOSPC; 1298 while (fat_get_entry(dir, &pos, &bh, &de) > -1) { 1299 /* check the maximum size of directory */ 1300 if (pos >= FAT_MAX_DIR_SIZE) 1301 goto error; 1302 1303 if (IS_FREE(de->name)) { 1304 if (prev != bh) { 1305 get_bh(bh); 1306 bhs[nr_bhs] = prev = bh; 1307 nr_bhs++; 1308 } 1309 free_slots++; 1310 if (free_slots == nr_slots) 1311 goto found; 1312 } else { 1313 for (i = 0; i < nr_bhs; i++) 1314 brelse(bhs[i]); 1315 prev = NULL; 1316 free_slots = nr_bhs = 0; 1317 } 1318 } 1319 if (dir->i_ino == MSDOS_ROOT_INO) { 1320 if (!is_fat32(sbi)) 1321 goto error; 1322 } else if (MSDOS_I(dir)->i_start == 0) { 1323 fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)", 1324 MSDOS_I(dir)->i_pos); 1325 err = -EIO; 1326 goto error; 1327 } 1328 1329 found: 1330 err = 0; 1331 pos -= free_slots * sizeof(*de); 1332 nr_slots -= free_slots; 1333 if (free_slots) { 1334 /* 1335 * Second stage: filling the free entries with new entries. 1336 * NOTE: If this slots has shortname, first, we write 1337 * the long name slots, then write the short name. 1338 */ 1339 int size = free_slots * sizeof(*de); 1340 int offset = pos & (sb->s_blocksize - 1); 1341 int long_bhs = nr_bhs - (nr_slots == 0); 1342 1343 /* Fill the long name slots. */ 1344 for (i = 0; i < long_bhs; i++) { 1345 int copy = min_t(int, sb->s_blocksize - offset, size); 1346 memcpy(bhs[i]->b_data + offset, slots, copy); 1347 mark_buffer_dirty_inode(bhs[i], dir); 1348 offset = 0; 1349 slots += copy; 1350 size -= copy; 1351 } 1352 if (long_bhs && IS_DIRSYNC(dir)) 1353 err = fat_sync_bhs(bhs, long_bhs); 1354 if (!err && i < nr_bhs) { 1355 /* Fill the short name slot. */ 1356 int copy = min_t(int, sb->s_blocksize - offset, size); 1357 memcpy(bhs[i]->b_data + offset, slots, copy); 1358 mark_buffer_dirty_inode(bhs[i], dir); 1359 if (IS_DIRSYNC(dir)) 1360 err = sync_dirty_buffer(bhs[i]); 1361 } 1362 for (i = 0; i < nr_bhs; i++) 1363 brelse(bhs[i]); 1364 if (err) 1365 goto error_remove; 1366 } 1367 1368 if (nr_slots) { 1369 int cluster, nr_cluster; 1370 1371 /* 1372 * Third stage: allocate the cluster for new entries. 1373 * And initialize the cluster with new entries, then 1374 * add the cluster to dir. 1375 */ 1376 cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster, 1377 &de, &bh, &i_pos); 1378 if (cluster < 0) { 1379 err = cluster; 1380 goto error_remove; 1381 } 1382 err = fat_chain_add(dir, cluster, nr_cluster); 1383 if (err) { 1384 fat_free_clusters(dir, cluster); 1385 goto error_remove; 1386 } 1387 if (dir->i_size & (sbi->cluster_size - 1)) { 1388 fat_fs_error(sb, "Odd directory size"); 1389 dir->i_size = (dir->i_size + sbi->cluster_size - 1) 1390 & ~((loff_t)sbi->cluster_size - 1); 1391 } 1392 dir->i_size += nr_cluster << sbi->cluster_bits; 1393 MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits; 1394 } 1395 sinfo->slot_off = pos; 1396 sinfo->de = de; 1397 sinfo->bh = bh; 1398 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 1399 1400 return 0; 1401 1402 error: 1403 brelse(bh); 1404 for (i = 0; i < nr_bhs; i++) 1405 brelse(bhs[i]); 1406 return err; 1407 1408 error_remove: 1409 brelse(bh); 1410 if (free_slots) 1411 __fat_remove_entries(dir, pos, free_slots); 1412 return err; 1413 } 1414 EXPORT_SYMBOL_GPL(fat_add_entries); 1415