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 * @dir: Pointer to the inode that represents the directory. 273 * @pos: On input, contains the starting position to read from. 274 * On output, updated with the new position. 275 * @bh: Pointer to the buffer head that may be used for reading directory 276 * entries. May be updated. 277 * @de: On input, points to the current directory entry. 278 * On output, points to the next directory entry. 279 * @unicode: Pointer to a buffer where the parsed Unicode long filename will be 280 * stored. 281 * @nr_slots: Pointer to a variable that will store the number of longname 282 * slots found. 283 * 284 * This function returns zero on success, negative value on error, or one of 285 * the following: 286 * 287 * %PARSE_INVALID - Directory entry is invalid. 288 * %PARSE_NOT_LONGNAME - Directory entry does not contain longname. 289 * %PARSE_EOF - Directory has no more entries. 290 */ 291 static int fat_parse_long(struct inode *dir, loff_t *pos, 292 struct buffer_head **bh, struct msdos_dir_entry **de, 293 wchar_t **unicode, unsigned char *nr_slots) 294 { 295 struct msdos_dir_slot *ds; 296 unsigned char id, slot, slots, alias_checksum; 297 298 if (!*unicode) { 299 *unicode = __getname(); 300 if (!*unicode) { 301 brelse(*bh); 302 return -ENOMEM; 303 } 304 } 305 parse_long: 306 ds = (struct msdos_dir_slot *)*de; 307 id = ds->id; 308 if (!(id & 0x40)) 309 return PARSE_INVALID; 310 slots = id & ~0x40; 311 if (slots > 20 || !slots) /* ceil(256 * 2 / 26) */ 312 return PARSE_INVALID; 313 *nr_slots = slots; 314 alias_checksum = ds->alias_checksum; 315 316 slot = slots; 317 while (1) { 318 int offset; 319 320 slot--; 321 offset = slot * 13; 322 fat16_towchar(*unicode + offset, ds->name0_4, 5); 323 fat16_towchar(*unicode + offset + 5, ds->name5_10, 6); 324 fat16_towchar(*unicode + offset + 11, ds->name11_12, 2); 325 326 if (ds->id & 0x40) 327 (*unicode)[offset + 13] = 0; 328 if (fat_get_entry(dir, pos, bh, de) < 0) 329 return PARSE_EOF; 330 if (slot == 0) 331 break; 332 ds = (struct msdos_dir_slot *)*de; 333 if (ds->attr != ATTR_EXT) 334 return PARSE_NOT_LONGNAME; 335 if ((ds->id & ~0x40) != slot) 336 goto parse_long; 337 if (ds->alias_checksum != alias_checksum) 338 goto parse_long; 339 } 340 if ((*de)->name[0] == DELETED_FLAG) 341 return PARSE_INVALID; 342 if ((*de)->attr == ATTR_EXT) 343 goto parse_long; 344 if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME)) 345 return PARSE_INVALID; 346 if (fat_checksum((*de)->name) != alias_checksum) 347 *nr_slots = 0; 348 349 return 0; 350 } 351 352 /** 353 * fat_parse_short - Parse MS-DOS (short) directory entry. 354 * @sb: superblock 355 * @de: directory entry to parse 356 * @name: FAT_MAX_SHORT_SIZE array in which to place extracted name 357 * @dot_hidden: Nonzero == prepend '.' to names with ATTR_HIDDEN 358 * 359 * Returns the number of characters extracted into 'name'. 360 */ 361 static int fat_parse_short(struct super_block *sb, 362 const struct msdos_dir_entry *de, 363 unsigned char *name, int dot_hidden) 364 { 365 const struct msdos_sb_info *sbi = MSDOS_SB(sb); 366 int isvfat = sbi->options.isvfat; 367 int nocase = sbi->options.nocase; 368 unsigned short opt_shortname = sbi->options.shortname; 369 struct nls_table *nls_disk = sbi->nls_disk; 370 wchar_t uni_name[14]; 371 unsigned char c, work[MSDOS_NAME]; 372 unsigned char *ptname = name; 373 int chi, chl, i, j, k; 374 int dotoffset = 0; 375 int name_len = 0, uni_len = 0; 376 377 if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) { 378 *ptname++ = '.'; 379 dotoffset = 1; 380 } 381 382 memcpy(work, de->name, sizeof(work)); 383 /* For an explanation of the special treatment of 0x05 in 384 * filenames, see msdos_format_name in namei_msdos.c 385 */ 386 if (work[0] == 0x05) 387 work[0] = 0xE5; 388 389 /* Filename */ 390 for (i = 0, j = 0; i < 8;) { 391 c = work[i]; 392 if (!c) 393 break; 394 chl = fat_shortname2uni(nls_disk, &work[i], 8 - i, 395 &uni_name[j++], opt_shortname, 396 de->lcase & CASE_LOWER_BASE); 397 if (chl <= 1) { 398 if (!isvfat) 399 ptname[i] = nocase ? c : fat_tolower(c); 400 i++; 401 if (c != ' ') { 402 name_len = i; 403 uni_len = j; 404 } 405 } else { 406 uni_len = j; 407 if (isvfat) 408 i += min(chl, 8-i); 409 else { 410 for (chi = 0; chi < chl && i < 8; chi++, i++) 411 ptname[i] = work[i]; 412 } 413 if (chl) 414 name_len = i; 415 } 416 } 417 418 i = name_len; 419 j = uni_len; 420 fat_short2uni(nls_disk, ".", 1, &uni_name[j++]); 421 if (!isvfat) 422 ptname[i] = '.'; 423 i++; 424 425 /* Extension */ 426 for (k = 8; k < MSDOS_NAME;) { 427 c = work[k]; 428 if (!c) 429 break; 430 chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k, 431 &uni_name[j++], opt_shortname, 432 de->lcase & CASE_LOWER_EXT); 433 if (chl <= 1) { 434 k++; 435 if (!isvfat) 436 ptname[i] = nocase ? c : fat_tolower(c); 437 i++; 438 if (c != ' ') { 439 name_len = i; 440 uni_len = j; 441 } 442 } else { 443 uni_len = j; 444 if (isvfat) { 445 int offset = min(chl, MSDOS_NAME-k); 446 k += offset; 447 i += offset; 448 } else { 449 for (chi = 0; chi < chl && k < MSDOS_NAME; 450 chi++, i++, k++) { 451 ptname[i] = work[k]; 452 } 453 } 454 if (chl) 455 name_len = i; 456 } 457 } 458 459 if (name_len > 0) { 460 name_len += dotoffset; 461 462 if (sbi->options.isvfat) { 463 uni_name[uni_len] = 0x0000; 464 name_len = fat_uni_to_x8(sb, uni_name, name, 465 FAT_MAX_SHORT_SIZE); 466 } 467 } 468 469 return name_len; 470 } 471 472 /* 473 * Return values: negative -> error/not found, 0 -> found. 474 */ 475 int fat_search_long(struct inode *inode, const unsigned char *name, 476 int name_len, struct fat_slot_info *sinfo) 477 { 478 struct super_block *sb = inode->i_sb; 479 struct msdos_sb_info *sbi = MSDOS_SB(sb); 480 struct buffer_head *bh = NULL; 481 struct msdos_dir_entry *de; 482 unsigned char nr_slots; 483 wchar_t *unicode = NULL; 484 unsigned char bufname[FAT_MAX_SHORT_SIZE]; 485 loff_t cpos = 0; 486 int err, len; 487 488 err = -ENOENT; 489 while (1) { 490 if (fat_get_entry(inode, &cpos, &bh, &de) == -1) 491 goto end_of_dir; 492 parse_record: 493 nr_slots = 0; 494 if (de->name[0] == DELETED_FLAG) 495 continue; 496 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) 497 continue; 498 if (de->attr != ATTR_EXT && IS_FREE(de->name)) 499 continue; 500 if (de->attr == ATTR_EXT) { 501 int status = fat_parse_long(inode, &cpos, &bh, &de, 502 &unicode, &nr_slots); 503 if (status < 0) { 504 err = status; 505 goto end_of_dir; 506 } else if (status == PARSE_INVALID) 507 continue; 508 else if (status == PARSE_NOT_LONGNAME) 509 goto parse_record; 510 else if (status == PARSE_EOF) 511 goto end_of_dir; 512 } 513 514 /* Never prepend '.' to hidden files here. 515 * That is done only for msdos mounts (and only when 516 * 'dotsOK=yes'); if we are executing here, it is in the 517 * context of a vfat mount. 518 */ 519 len = fat_parse_short(sb, de, bufname, 0); 520 if (len == 0) 521 continue; 522 523 /* Compare shortname */ 524 if (fat_name_match(sbi, name, name_len, bufname, len)) 525 goto found; 526 527 if (nr_slots) { 528 void *longname = unicode + FAT_MAX_UNI_CHARS; 529 int size = PATH_MAX - FAT_MAX_UNI_SIZE; 530 531 /* Compare longname */ 532 len = fat_uni_to_x8(sb, unicode, longname, size); 533 if (fat_name_match(sbi, name, name_len, longname, len)) 534 goto found; 535 } 536 } 537 538 found: 539 nr_slots++; /* include the de */ 540 sinfo->slot_off = cpos - nr_slots * sizeof(*de); 541 sinfo->nr_slots = nr_slots; 542 sinfo->de = de; 543 sinfo->bh = bh; 544 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 545 err = 0; 546 end_of_dir: 547 if (unicode) 548 __putname(unicode); 549 550 return err; 551 } 552 EXPORT_SYMBOL_GPL(fat_search_long); 553 554 struct fat_ioctl_filldir_callback { 555 struct dir_context ctx; 556 void __user *dirent; 557 int result; 558 /* for dir ioctl */ 559 const char *longname; 560 int long_len; 561 const char *shortname; 562 int short_len; 563 }; 564 565 static int __fat_readdir(struct inode *inode, struct file *file, 566 struct dir_context *ctx, int short_only, 567 struct fat_ioctl_filldir_callback *both) 568 { 569 struct super_block *sb = inode->i_sb; 570 struct msdos_sb_info *sbi = MSDOS_SB(sb); 571 struct buffer_head *bh; 572 struct msdos_dir_entry *de; 573 unsigned char nr_slots; 574 wchar_t *unicode = NULL; 575 unsigned char bufname[FAT_MAX_SHORT_SIZE]; 576 int isvfat = sbi->options.isvfat; 577 const char *fill_name = NULL; 578 int fake_offset = 0; 579 loff_t cpos; 580 int short_len = 0, fill_len = 0; 581 int ret = 0; 582 583 mutex_lock(&sbi->s_lock); 584 585 cpos = ctx->pos; 586 /* Fake . and .. for the root directory. */ 587 if (inode->i_ino == MSDOS_ROOT_INO) { 588 if (!dir_emit_dots(file, ctx)) 589 goto out; 590 if (ctx->pos == 2) { 591 fake_offset = 1; 592 cpos = 0; 593 } 594 } 595 if (cpos & (sizeof(struct msdos_dir_entry) - 1)) { 596 ret = -ENOENT; 597 goto out; 598 } 599 600 bh = NULL; 601 get_new: 602 if (fat_get_entry(inode, &cpos, &bh, &de) == -1) 603 goto end_of_dir; 604 parse_record: 605 nr_slots = 0; 606 /* 607 * Check for long filename entry, but if short_only, we don't 608 * need to parse long filename. 609 */ 610 if (isvfat && !short_only) { 611 if (de->name[0] == DELETED_FLAG) 612 goto record_end; 613 if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME)) 614 goto record_end; 615 if (de->attr != ATTR_EXT && IS_FREE(de->name)) 616 goto record_end; 617 } else { 618 if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name)) 619 goto record_end; 620 } 621 622 if (isvfat && de->attr == ATTR_EXT) { 623 int status = fat_parse_long(inode, &cpos, &bh, &de, 624 &unicode, &nr_slots); 625 if (status < 0) { 626 bh = NULL; 627 ret = status; 628 goto end_of_dir; 629 } else if (status == PARSE_INVALID) 630 goto record_end; 631 else if (status == PARSE_NOT_LONGNAME) 632 goto parse_record; 633 else if (status == PARSE_EOF) 634 goto end_of_dir; 635 636 if (nr_slots) { 637 void *longname = unicode + FAT_MAX_UNI_CHARS; 638 int size = PATH_MAX - FAT_MAX_UNI_SIZE; 639 int len = fat_uni_to_x8(sb, unicode, longname, size); 640 641 fill_name = longname; 642 fill_len = len; 643 /* !both && !short_only, so we don't need shortname. */ 644 if (!both) 645 goto start_filldir; 646 647 short_len = fat_parse_short(sb, de, bufname, 648 sbi->options.dotsOK); 649 if (short_len == 0) 650 goto record_end; 651 /* hack for fat_ioctl_filldir() */ 652 both->longname = fill_name; 653 both->long_len = fill_len; 654 both->shortname = bufname; 655 both->short_len = short_len; 656 fill_name = NULL; 657 fill_len = 0; 658 goto start_filldir; 659 } 660 } 661 662 short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK); 663 if (short_len == 0) 664 goto record_end; 665 666 fill_name = bufname; 667 fill_len = short_len; 668 669 start_filldir: 670 ctx->pos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry); 671 if (fake_offset && ctx->pos < 2) 672 ctx->pos = 2; 673 674 if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME)) { 675 if (!dir_emit_dot(file, ctx)) 676 goto fill_failed; 677 } else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { 678 if (!dir_emit_dotdot(file, ctx)) 679 goto fill_failed; 680 } else { 681 unsigned long inum; 682 loff_t i_pos = fat_make_i_pos(sb, bh, de); 683 struct inode *tmp = fat_iget(sb, i_pos); 684 if (tmp) { 685 inum = tmp->i_ino; 686 iput(tmp); 687 } else 688 inum = iunique(sb, MSDOS_ROOT_INO); 689 if (!dir_emit(ctx, fill_name, fill_len, inum, 690 (de->attr & ATTR_DIR) ? DT_DIR : DT_REG)) 691 goto fill_failed; 692 } 693 694 record_end: 695 fake_offset = 0; 696 ctx->pos = cpos; 697 goto get_new; 698 699 end_of_dir: 700 if (fake_offset && cpos < 2) 701 ctx->pos = 2; 702 else 703 ctx->pos = cpos; 704 fill_failed: 705 brelse(bh); 706 if (unicode) 707 __putname(unicode); 708 out: 709 mutex_unlock(&sbi->s_lock); 710 711 return ret; 712 } 713 714 static int fat_readdir(struct file *file, struct dir_context *ctx) 715 { 716 return __fat_readdir(file_inode(file), file, ctx, 0, NULL); 717 } 718 719 #define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type) \ 720 static bool func(struct dir_context *ctx, const char *name, int name_len, \ 721 loff_t offset, u64 ino, unsigned int d_type) \ 722 { \ 723 struct fat_ioctl_filldir_callback *buf = \ 724 container_of(ctx, struct fat_ioctl_filldir_callback, ctx); \ 725 struct dirent_type __user *d1 = buf->dirent; \ 726 struct dirent_type __user *d2 = d1 + 1; \ 727 \ 728 if (buf->result) \ 729 return false; \ 730 buf->result++; \ 731 \ 732 if (name != NULL) { \ 733 /* dirent has only short name */ \ 734 if (name_len >= sizeof(d1->d_name)) \ 735 name_len = sizeof(d1->d_name) - 1; \ 736 \ 737 if (put_user(0, &d2->d_name[0]) || \ 738 put_user(0, &d2->d_reclen) || \ 739 copy_to_user(d1->d_name, name, name_len) || \ 740 put_user(0, d1->d_name + name_len) || \ 741 put_user(name_len, &d1->d_reclen)) \ 742 goto efault; \ 743 } else { \ 744 /* dirent has short and long name */ \ 745 const char *longname = buf->longname; \ 746 int long_len = buf->long_len; \ 747 const char *shortname = buf->shortname; \ 748 int short_len = buf->short_len; \ 749 \ 750 if (long_len >= sizeof(d1->d_name)) \ 751 long_len = sizeof(d1->d_name) - 1; \ 752 if (short_len >= sizeof(d1->d_name)) \ 753 short_len = sizeof(d1->d_name) - 1; \ 754 \ 755 if (copy_to_user(d2->d_name, longname, long_len) || \ 756 put_user(0, d2->d_name + long_len) || \ 757 put_user(long_len, &d2->d_reclen) || \ 758 put_user(ino, &d2->d_ino) || \ 759 put_user(offset, &d2->d_off) || \ 760 copy_to_user(d1->d_name, shortname, short_len) || \ 761 put_user(0, d1->d_name + short_len) || \ 762 put_user(short_len, &d1->d_reclen)) \ 763 goto efault; \ 764 } \ 765 return true; \ 766 efault: \ 767 buf->result = -EFAULT; \ 768 return false; \ 769 } 770 771 FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent) 772 773 static int fat_ioctl_readdir(struct inode *inode, struct file *file, 774 void __user *dirent, filldir_t filldir, 775 int short_only, int both) 776 { 777 struct fat_ioctl_filldir_callback buf = { 778 .ctx.actor = filldir, 779 .dirent = dirent 780 }; 781 int ret; 782 783 buf.dirent = dirent; 784 buf.result = 0; 785 inode_lock_shared(inode); 786 buf.ctx.pos = file->f_pos; 787 ret = -ENOENT; 788 if (!IS_DEADDIR(inode)) { 789 ret = __fat_readdir(inode, file, &buf.ctx, 790 short_only, both ? &buf : NULL); 791 file->f_pos = buf.ctx.pos; 792 } 793 inode_unlock_shared(inode); 794 if (ret >= 0) 795 ret = buf.result; 796 return ret; 797 } 798 799 static long fat_dir_ioctl(struct file *filp, unsigned int cmd, 800 unsigned long arg) 801 { 802 struct inode *inode = file_inode(filp); 803 struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg; 804 int short_only, both; 805 806 switch (cmd) { 807 case VFAT_IOCTL_READDIR_SHORT: 808 short_only = 1; 809 both = 0; 810 break; 811 case VFAT_IOCTL_READDIR_BOTH: 812 short_only = 0; 813 both = 1; 814 break; 815 default: 816 return fat_generic_ioctl(filp, cmd, arg); 817 } 818 819 /* 820 * Yes, we don't need this put_user() absolutely. However old 821 * code didn't return the right value. So, app use this value, 822 * in order to check whether it is EOF. 823 */ 824 if (put_user(0, &d1->d_reclen)) 825 return -EFAULT; 826 827 return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir, 828 short_only, both); 829 } 830 831 #ifdef CONFIG_COMPAT 832 #define VFAT_IOCTL_READDIR_BOTH32 _IOR('r', 1, struct compat_dirent[2]) 833 #define VFAT_IOCTL_READDIR_SHORT32 _IOR('r', 2, struct compat_dirent[2]) 834 835 FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent) 836 837 static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd, 838 unsigned long arg) 839 { 840 struct inode *inode = file_inode(filp); 841 struct compat_dirent __user *d1 = compat_ptr(arg); 842 int short_only, both; 843 844 switch (cmd) { 845 case VFAT_IOCTL_READDIR_SHORT32: 846 short_only = 1; 847 both = 0; 848 break; 849 case VFAT_IOCTL_READDIR_BOTH32: 850 short_only = 0; 851 both = 1; 852 break; 853 default: 854 return fat_generic_ioctl(filp, cmd, (unsigned long)arg); 855 } 856 857 /* 858 * Yes, we don't need this put_user() absolutely. However old 859 * code didn't return the right value. So, app use this value, 860 * in order to check whether it is EOF. 861 */ 862 if (put_user(0, &d1->d_reclen)) 863 return -EFAULT; 864 865 return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir, 866 short_only, both); 867 } 868 #endif /* CONFIG_COMPAT */ 869 870 const struct file_operations fat_dir_operations = { 871 .llseek = generic_file_llseek, 872 .read = generic_read_dir, 873 .iterate_shared = fat_readdir, 874 .unlocked_ioctl = fat_dir_ioctl, 875 #ifdef CONFIG_COMPAT 876 .compat_ioctl = fat_compat_dir_ioctl, 877 #endif 878 .fsync = fat_file_fsync, 879 }; 880 881 static int fat_get_short_entry(struct inode *dir, loff_t *pos, 882 struct buffer_head **bh, 883 struct msdos_dir_entry **de) 884 { 885 while (fat_get_entry(dir, pos, bh, de) >= 0) { 886 /* free entry or long name entry or volume label */ 887 if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME)) 888 return 0; 889 } 890 return -ENOENT; 891 } 892 893 /* 894 * The ".." entry can not provide the "struct fat_slot_info" information 895 * for inode, nor a usable i_pos. So, this function provides some information 896 * only. 897 * 898 * Since this function walks through the on-disk inodes within a directory, 899 * callers are responsible for taking any locks necessary to prevent the 900 * directory from changing. 901 */ 902 int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, 903 struct msdos_dir_entry **de) 904 { 905 loff_t offset = 0; 906 907 *de = NULL; 908 while (fat_get_short_entry(dir, &offset, bh, de) >= 0) { 909 if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) 910 return 0; 911 } 912 return -ENOENT; 913 } 914 EXPORT_SYMBOL_GPL(fat_get_dotdot_entry); 915 916 /* See if directory is empty */ 917 int fat_dir_empty(struct inode *dir) 918 { 919 struct buffer_head *bh; 920 struct msdos_dir_entry *de; 921 loff_t cpos; 922 int result = 0; 923 924 bh = NULL; 925 cpos = 0; 926 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { 927 if (strncmp(de->name, MSDOS_DOT , MSDOS_NAME) && 928 strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) { 929 result = -ENOTEMPTY; 930 break; 931 } 932 } 933 brelse(bh); 934 return result; 935 } 936 EXPORT_SYMBOL_GPL(fat_dir_empty); 937 938 /* 939 * fat_subdirs counts the number of sub-directories of dir. It can be run 940 * on directories being created. 941 */ 942 int fat_subdirs(struct inode *dir) 943 { 944 struct buffer_head *bh; 945 struct msdos_dir_entry *de; 946 loff_t cpos; 947 int count = 0; 948 949 bh = NULL; 950 cpos = 0; 951 while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) { 952 if (de->attr & ATTR_DIR) 953 count++; 954 } 955 brelse(bh); 956 return count; 957 } 958 959 /* 960 * Scans a directory for a given file (name points to its formatted name). 961 * Returns an error code or zero. 962 */ 963 int fat_scan(struct inode *dir, const unsigned char *name, 964 struct fat_slot_info *sinfo) 965 { 966 struct super_block *sb = dir->i_sb; 967 968 sinfo->slot_off = 0; 969 sinfo->bh = NULL; 970 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh, 971 &sinfo->de) >= 0) { 972 if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) { 973 sinfo->slot_off -= sizeof(*sinfo->de); 974 sinfo->nr_slots = 1; 975 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 976 return 0; 977 } 978 } 979 return -ENOENT; 980 } 981 EXPORT_SYMBOL_GPL(fat_scan); 982 983 /* 984 * Scans a directory for a given logstart. 985 * Returns an error code or zero. 986 */ 987 int fat_scan_logstart(struct inode *dir, int i_logstart, 988 struct fat_slot_info *sinfo) 989 { 990 struct super_block *sb = dir->i_sb; 991 992 sinfo->slot_off = 0; 993 sinfo->bh = NULL; 994 while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh, 995 &sinfo->de) >= 0) { 996 if (fat_get_start(MSDOS_SB(sb), sinfo->de) == i_logstart) { 997 sinfo->slot_off -= sizeof(*sinfo->de); 998 sinfo->nr_slots = 1; 999 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 1000 return 0; 1001 } 1002 } 1003 return -ENOENT; 1004 } 1005 1006 static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots) 1007 { 1008 struct super_block *sb = dir->i_sb; 1009 struct buffer_head *bh; 1010 struct msdos_dir_entry *de, *endp; 1011 int err = 0, orig_slots; 1012 1013 while (nr_slots) { 1014 bh = NULL; 1015 if (fat_get_entry(dir, &pos, &bh, &de) < 0) { 1016 err = -EIO; 1017 break; 1018 } 1019 1020 orig_slots = nr_slots; 1021 endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize); 1022 while (nr_slots && de < endp) { 1023 de->name[0] = DELETED_FLAG; 1024 de++; 1025 nr_slots--; 1026 } 1027 mark_buffer_dirty_inode(bh, dir); 1028 if (IS_DIRSYNC(dir)) 1029 err = sync_dirty_buffer(bh); 1030 brelse(bh); 1031 if (err) 1032 break; 1033 1034 /* pos is *next* de's position, so this does `- sizeof(de)' */ 1035 pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de); 1036 } 1037 1038 return err; 1039 } 1040 1041 int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo) 1042 { 1043 struct super_block *sb = dir->i_sb; 1044 struct msdos_dir_entry *de; 1045 struct buffer_head *bh; 1046 int err = 0, nr_slots; 1047 1048 /* 1049 * First stage: Remove the shortname. By this, the directory 1050 * entry is removed. 1051 */ 1052 nr_slots = sinfo->nr_slots; 1053 de = sinfo->de; 1054 sinfo->de = NULL; 1055 bh = sinfo->bh; 1056 sinfo->bh = NULL; 1057 while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) { 1058 de->name[0] = DELETED_FLAG; 1059 de--; 1060 nr_slots--; 1061 } 1062 mark_buffer_dirty_inode(bh, dir); 1063 if (IS_DIRSYNC(dir)) 1064 err = sync_dirty_buffer(bh); 1065 brelse(bh); 1066 if (err) 1067 return err; 1068 inode_inc_iversion(dir); 1069 1070 if (nr_slots) { 1071 /* 1072 * Second stage: remove the remaining longname slots. 1073 * (This directory entry is already removed, and so return 1074 * the success) 1075 */ 1076 err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots); 1077 if (err) { 1078 fat_msg(sb, KERN_WARNING, 1079 "Couldn't remove the long name slots"); 1080 } 1081 } 1082 1083 fat_truncate_time(dir, NULL, S_ATIME|S_MTIME); 1084 if (IS_DIRSYNC(dir)) 1085 (void)fat_sync_inode(dir); 1086 else 1087 mark_inode_dirty(dir); 1088 1089 return 0; 1090 } 1091 EXPORT_SYMBOL_GPL(fat_remove_entries); 1092 1093 static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used, 1094 struct buffer_head **bhs, int nr_bhs) 1095 { 1096 struct super_block *sb = dir->i_sb; 1097 sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus; 1098 int err, i, n; 1099 1100 /* Zeroing the unused blocks on this cluster */ 1101 blknr += nr_used; 1102 n = nr_used; 1103 while (blknr < last_blknr) { 1104 bhs[n] = sb_getblk(sb, blknr); 1105 if (!bhs[n]) { 1106 err = -ENOMEM; 1107 goto error; 1108 } 1109 /* Avoid race with userspace read via bdev */ 1110 lock_buffer(bhs[n]); 1111 memset(bhs[n]->b_data, 0, sb->s_blocksize); 1112 set_buffer_uptodate(bhs[n]); 1113 unlock_buffer(bhs[n]); 1114 mark_buffer_dirty_inode(bhs[n], dir); 1115 1116 n++; 1117 blknr++; 1118 if (n == nr_bhs) { 1119 if (IS_DIRSYNC(dir)) { 1120 err = fat_sync_bhs(bhs, n); 1121 if (err) 1122 goto error; 1123 } 1124 for (i = 0; i < n; i++) 1125 brelse(bhs[i]); 1126 n = 0; 1127 } 1128 } 1129 if (IS_DIRSYNC(dir)) { 1130 err = fat_sync_bhs(bhs, n); 1131 if (err) 1132 goto error; 1133 } 1134 for (i = 0; i < n; i++) 1135 brelse(bhs[i]); 1136 1137 return 0; 1138 1139 error: 1140 for (i = 0; i < n; i++) 1141 bforget(bhs[i]); 1142 return err; 1143 } 1144 1145 int fat_alloc_new_dir(struct inode *dir, struct timespec64 *ts) 1146 { 1147 struct super_block *sb = dir->i_sb; 1148 struct msdos_sb_info *sbi = MSDOS_SB(sb); 1149 struct buffer_head *bhs[MAX_BUF_PER_PAGE]; 1150 struct msdos_dir_entry *de; 1151 sector_t blknr; 1152 __le16 date, time; 1153 u8 time_cs; 1154 int err, cluster; 1155 1156 err = fat_alloc_clusters(dir, &cluster, 1); 1157 if (err) 1158 goto error; 1159 1160 blknr = fat_clus_to_blknr(sbi, cluster); 1161 bhs[0] = sb_getblk(sb, blknr); 1162 if (!bhs[0]) { 1163 err = -ENOMEM; 1164 goto error_free; 1165 } 1166 1167 fat_time_unix2fat(sbi, ts, &time, &date, &time_cs); 1168 1169 de = (struct msdos_dir_entry *)bhs[0]->b_data; 1170 /* Avoid race with userspace read via bdev */ 1171 lock_buffer(bhs[0]); 1172 /* filling the new directory slots ("." and ".." entries) */ 1173 memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME); 1174 memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME); 1175 de->attr = de[1].attr = ATTR_DIR; 1176 de[0].lcase = de[1].lcase = 0; 1177 de[0].time = de[1].time = time; 1178 de[0].date = de[1].date = date; 1179 if (sbi->options.isvfat) { 1180 /* extra timestamps */ 1181 de[0].ctime = de[1].ctime = time; 1182 de[0].ctime_cs = de[1].ctime_cs = time_cs; 1183 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date; 1184 } else { 1185 de[0].ctime = de[1].ctime = 0; 1186 de[0].ctime_cs = de[1].ctime_cs = 0; 1187 de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0; 1188 } 1189 fat_set_start(&de[0], cluster); 1190 fat_set_start(&de[1], MSDOS_I(dir)->i_logstart); 1191 de[0].size = de[1].size = 0; 1192 memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de)); 1193 set_buffer_uptodate(bhs[0]); 1194 unlock_buffer(bhs[0]); 1195 mark_buffer_dirty_inode(bhs[0], dir); 1196 1197 err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE); 1198 if (err) 1199 goto error_free; 1200 1201 return cluster; 1202 1203 error_free: 1204 fat_free_clusters(dir, cluster); 1205 error: 1206 return err; 1207 } 1208 EXPORT_SYMBOL_GPL(fat_alloc_new_dir); 1209 1210 static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots, 1211 int *nr_cluster, struct msdos_dir_entry **de, 1212 struct buffer_head **bh, loff_t *i_pos) 1213 { 1214 struct super_block *sb = dir->i_sb; 1215 struct msdos_sb_info *sbi = MSDOS_SB(sb); 1216 struct buffer_head *bhs[MAX_BUF_PER_PAGE]; 1217 sector_t blknr, start_blknr, last_blknr; 1218 unsigned long size, copy; 1219 int err, i, n, offset, cluster[2]; 1220 1221 /* 1222 * The minimum cluster size is 512bytes, and maximum entry 1223 * size is 32*slots (672bytes). So, iff the cluster size is 1224 * 512bytes, we may need two clusters. 1225 */ 1226 size = nr_slots * sizeof(struct msdos_dir_entry); 1227 *nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits; 1228 BUG_ON(*nr_cluster > 2); 1229 1230 err = fat_alloc_clusters(dir, cluster, *nr_cluster); 1231 if (err) 1232 goto error; 1233 1234 /* 1235 * First stage: Fill the directory entry. NOTE: This cluster 1236 * is not referenced from any inode yet, so updates order is 1237 * not important. 1238 */ 1239 i = n = copy = 0; 1240 do { 1241 start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]); 1242 last_blknr = start_blknr + sbi->sec_per_clus; 1243 while (blknr < last_blknr) { 1244 bhs[n] = sb_getblk(sb, blknr); 1245 if (!bhs[n]) { 1246 err = -ENOMEM; 1247 goto error_nomem; 1248 } 1249 1250 /* fill the directory entry */ 1251 copy = min(size, sb->s_blocksize); 1252 /* Avoid race with userspace read via bdev */ 1253 lock_buffer(bhs[n]); 1254 memcpy(bhs[n]->b_data, slots, copy); 1255 set_buffer_uptodate(bhs[n]); 1256 unlock_buffer(bhs[n]); 1257 mark_buffer_dirty_inode(bhs[n], dir); 1258 slots += copy; 1259 size -= copy; 1260 if (!size) 1261 break; 1262 n++; 1263 blknr++; 1264 } 1265 } while (++i < *nr_cluster); 1266 1267 memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy); 1268 offset = copy - sizeof(struct msdos_dir_entry); 1269 get_bh(bhs[n]); 1270 *bh = bhs[n]; 1271 *de = (struct msdos_dir_entry *)((*bh)->b_data + offset); 1272 *i_pos = fat_make_i_pos(sb, *bh, *de); 1273 1274 /* Second stage: clear the rest of cluster, and write outs */ 1275 err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE); 1276 if (err) 1277 goto error_free; 1278 1279 return cluster[0]; 1280 1281 error_free: 1282 brelse(*bh); 1283 *bh = NULL; 1284 n = 0; 1285 error_nomem: 1286 for (i = 0; i < n; i++) 1287 bforget(bhs[i]); 1288 fat_free_clusters(dir, cluster[0]); 1289 error: 1290 return err; 1291 } 1292 1293 int fat_add_entries(struct inode *dir, void *slots, int nr_slots, 1294 struct fat_slot_info *sinfo) 1295 { 1296 struct super_block *sb = dir->i_sb; 1297 struct msdos_sb_info *sbi = MSDOS_SB(sb); 1298 struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */ 1299 struct msdos_dir_entry *de; 1300 int err, free_slots, i, nr_bhs; 1301 loff_t pos, i_pos; 1302 1303 sinfo->nr_slots = nr_slots; 1304 1305 /* First stage: search free directory entries */ 1306 free_slots = nr_bhs = 0; 1307 bh = prev = NULL; 1308 pos = 0; 1309 err = -ENOSPC; 1310 while (fat_get_entry(dir, &pos, &bh, &de) > -1) { 1311 /* check the maximum size of directory */ 1312 if (pos >= FAT_MAX_DIR_SIZE) 1313 goto error; 1314 1315 if (IS_FREE(de->name)) { 1316 if (prev != bh) { 1317 get_bh(bh); 1318 bhs[nr_bhs] = prev = bh; 1319 nr_bhs++; 1320 } 1321 free_slots++; 1322 if (free_slots == nr_slots) 1323 goto found; 1324 } else { 1325 for (i = 0; i < nr_bhs; i++) 1326 brelse(bhs[i]); 1327 prev = NULL; 1328 free_slots = nr_bhs = 0; 1329 } 1330 } 1331 if (dir->i_ino == MSDOS_ROOT_INO) { 1332 if (!is_fat32(sbi)) 1333 goto error; 1334 } else if (MSDOS_I(dir)->i_start == 0) { 1335 fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)", 1336 MSDOS_I(dir)->i_pos); 1337 err = -EIO; 1338 goto error; 1339 } 1340 1341 found: 1342 err = 0; 1343 pos -= free_slots * sizeof(*de); 1344 nr_slots -= free_slots; 1345 if (free_slots) { 1346 /* 1347 * Second stage: filling the free entries with new entries. 1348 * NOTE: If this slots has shortname, first, we write 1349 * the long name slots, then write the short name. 1350 */ 1351 int size = free_slots * sizeof(*de); 1352 int offset = pos & (sb->s_blocksize - 1); 1353 int long_bhs = nr_bhs - (nr_slots == 0); 1354 1355 /* Fill the long name slots. */ 1356 for (i = 0; i < long_bhs; i++) { 1357 int copy = min_t(int, sb->s_blocksize - offset, size); 1358 memcpy(bhs[i]->b_data + offset, slots, copy); 1359 mark_buffer_dirty_inode(bhs[i], dir); 1360 offset = 0; 1361 slots += copy; 1362 size -= copy; 1363 } 1364 if (long_bhs && IS_DIRSYNC(dir)) 1365 err = fat_sync_bhs(bhs, long_bhs); 1366 if (!err && i < nr_bhs) { 1367 /* Fill the short name slot. */ 1368 int copy = min_t(int, sb->s_blocksize - offset, size); 1369 memcpy(bhs[i]->b_data + offset, slots, copy); 1370 mark_buffer_dirty_inode(bhs[i], dir); 1371 if (IS_DIRSYNC(dir)) 1372 err = sync_dirty_buffer(bhs[i]); 1373 } 1374 for (i = 0; i < nr_bhs; i++) 1375 brelse(bhs[i]); 1376 if (err) 1377 goto error_remove; 1378 } 1379 1380 if (nr_slots) { 1381 int cluster, nr_cluster; 1382 1383 /* 1384 * Third stage: allocate the cluster for new entries. 1385 * And initialize the cluster with new entries, then 1386 * add the cluster to dir. 1387 */ 1388 cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster, 1389 &de, &bh, &i_pos); 1390 if (cluster < 0) { 1391 err = cluster; 1392 goto error_remove; 1393 } 1394 err = fat_chain_add(dir, cluster, nr_cluster); 1395 if (err) { 1396 fat_free_clusters(dir, cluster); 1397 goto error_remove; 1398 } 1399 if (dir->i_size & (sbi->cluster_size - 1)) { 1400 fat_fs_error(sb, "Odd directory size"); 1401 dir->i_size = (dir->i_size + sbi->cluster_size - 1) 1402 & ~((loff_t)sbi->cluster_size - 1); 1403 } 1404 dir->i_size += nr_cluster << sbi->cluster_bits; 1405 MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits; 1406 } 1407 sinfo->slot_off = pos; 1408 sinfo->de = de; 1409 sinfo->bh = bh; 1410 sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de); 1411 1412 return 0; 1413 1414 error: 1415 brelse(bh); 1416 for (i = 0; i < nr_bhs; i++) 1417 brelse(bhs[i]); 1418 return err; 1419 1420 error_remove: 1421 brelse(bh); 1422 if (free_slots) 1423 __fat_remove_entries(dir, pos, free_slots); 1424 return err; 1425 } 1426 EXPORT_SYMBOL_GPL(fat_add_entries); 1427