1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. 4 */ 5 6 #include <linux/iversion.h> 7 #include <linux/namei.h> 8 #include <linux/slab.h> 9 #include <linux/buffer_head.h> 10 #include <linux/nls.h> 11 12 #include "exfat_raw.h" 13 #include "exfat_fs.h" 14 15 static inline unsigned long exfat_d_version(struct dentry *dentry) 16 { 17 return (unsigned long) dentry->d_fsdata; 18 } 19 20 static inline void exfat_d_version_set(struct dentry *dentry, 21 unsigned long version) 22 { 23 dentry->d_fsdata = (void *) version; 24 } 25 26 /* 27 * If new entry was created in the parent, it could create the 8.3 alias (the 28 * shortname of logname). So, the parent may have the negative-dentry which 29 * matches the created 8.3 alias. 30 * 31 * If it happened, the negative dentry isn't actually negative anymore. So, 32 * drop it. 33 */ 34 static int exfat_d_revalidate(struct dentry *dentry, unsigned int flags) 35 { 36 int ret; 37 38 if (flags & LOOKUP_RCU) 39 return -ECHILD; 40 41 /* 42 * This is not negative dentry. Always valid. 43 * 44 * Note, rename() to existing directory entry will have ->d_inode, and 45 * will use existing name which isn't specified name by user. 46 * 47 * We may be able to drop this positive dentry here. But dropping 48 * positive dentry isn't good idea. So it's unsupported like 49 * rename("filename", "FILENAME") for now. 50 */ 51 if (d_really_is_positive(dentry)) 52 return 1; 53 54 /* 55 * Drop the negative dentry, in order to make sure to use the case 56 * sensitive name which is specified by user if this is for creation. 57 */ 58 if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET)) 59 return 0; 60 61 spin_lock(&dentry->d_lock); 62 ret = inode_eq_iversion(d_inode(dentry->d_parent), 63 exfat_d_version(dentry)); 64 spin_unlock(&dentry->d_lock); 65 return ret; 66 } 67 68 /* returns the length of a struct qstr, ignoring trailing dots if necessary */ 69 static unsigned int exfat_striptail_len(unsigned int len, const char *name, 70 bool keep_last_dots) 71 { 72 if (!keep_last_dots) { 73 while (len && name[len - 1] == '.') 74 len--; 75 } 76 return len; 77 } 78 79 /* 80 * Compute the hash for the exfat name corresponding to the dentry. If the name 81 * is invalid, we leave the hash code unchanged so that the existing dentry can 82 * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate. 83 */ 84 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr) 85 { 86 struct super_block *sb = dentry->d_sb; 87 struct nls_table *t = EXFAT_SB(sb)->nls_io; 88 const unsigned char *name = qstr->name; 89 unsigned int len = exfat_striptail_len(qstr->len, qstr->name, 90 EXFAT_SB(sb)->options.keep_last_dots); 91 unsigned long hash = init_name_hash(dentry); 92 int i, charlen; 93 wchar_t c; 94 95 for (i = 0; i < len; i += charlen) { 96 charlen = t->char2uni(&name[i], len - i, &c); 97 if (charlen < 0) 98 return charlen; 99 hash = partial_name_hash(exfat_toupper(sb, c), hash); 100 } 101 102 qstr->hash = end_name_hash(hash); 103 return 0; 104 } 105 106 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len, 107 const char *str, const struct qstr *name) 108 { 109 struct super_block *sb = dentry->d_sb; 110 struct nls_table *t = EXFAT_SB(sb)->nls_io; 111 unsigned int alen = exfat_striptail_len(name->len, name->name, 112 EXFAT_SB(sb)->options.keep_last_dots); 113 unsigned int blen = exfat_striptail_len(len, str, 114 EXFAT_SB(sb)->options.keep_last_dots); 115 wchar_t c1, c2; 116 int charlen, i; 117 118 if (alen != blen) 119 return 1; 120 121 for (i = 0; i < len; i += charlen) { 122 charlen = t->char2uni(&name->name[i], alen - i, &c1); 123 if (charlen < 0) 124 return 1; 125 if (charlen != t->char2uni(&str[i], blen - i, &c2)) 126 return 1; 127 128 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2)) 129 return 1; 130 } 131 132 return 0; 133 } 134 135 const struct dentry_operations exfat_dentry_ops = { 136 .d_revalidate = exfat_d_revalidate, 137 .d_hash = exfat_d_hash, 138 .d_compare = exfat_d_cmp, 139 }; 140 141 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr) 142 { 143 struct super_block *sb = dentry->d_sb; 144 const unsigned char *name = qstr->name; 145 unsigned int len = exfat_striptail_len(qstr->len, qstr->name, 146 EXFAT_SB(sb)->options.keep_last_dots); 147 unsigned long hash = init_name_hash(dentry); 148 int i, charlen; 149 unicode_t u; 150 151 for (i = 0; i < len; i += charlen) { 152 charlen = utf8_to_utf32(&name[i], len - i, &u); 153 if (charlen < 0) 154 return charlen; 155 156 /* 157 * exfat_toupper() works only for code points up to the U+FFFF. 158 */ 159 hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u, 160 hash); 161 } 162 163 qstr->hash = end_name_hash(hash); 164 return 0; 165 } 166 167 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len, 168 const char *str, const struct qstr *name) 169 { 170 struct super_block *sb = dentry->d_sb; 171 unsigned int alen = exfat_striptail_len(name->len, name->name, 172 EXFAT_SB(sb)->options.keep_last_dots); 173 unsigned int blen = exfat_striptail_len(len, str, 174 EXFAT_SB(sb)->options.keep_last_dots); 175 176 unicode_t u_a, u_b; 177 int charlen, i; 178 179 if (alen != blen) 180 return 1; 181 182 for (i = 0; i < alen; i += charlen) { 183 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a); 184 if (charlen < 0) 185 return 1; 186 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b)) 187 return 1; 188 189 if (u_a <= 0xFFFF && u_b <= 0xFFFF) { 190 if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b)) 191 return 1; 192 } else { 193 if (u_a != u_b) 194 return 1; 195 } 196 } 197 198 return 0; 199 } 200 201 const struct dentry_operations exfat_utf8_dentry_ops = { 202 .d_revalidate = exfat_d_revalidate, 203 .d_hash = exfat_utf8_d_hash, 204 .d_compare = exfat_utf8_d_cmp, 205 }; 206 207 /* search EMPTY CONTINUOUS "num_entries" entries */ 208 static int exfat_search_empty_slot(struct super_block *sb, 209 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir, 210 int num_entries, struct exfat_entry_set_cache *es) 211 { 212 int i, dentry, ret; 213 int dentries_per_clu; 214 struct exfat_chain clu; 215 struct exfat_sb_info *sbi = EXFAT_SB(sb); 216 int total_entries = EXFAT_CLU_TO_DEN(p_dir->size, sbi); 217 218 dentries_per_clu = sbi->dentries_per_clu; 219 220 if (hint_femp->eidx != EXFAT_HINT_NONE) { 221 dentry = hint_femp->eidx; 222 223 /* 224 * If hint_femp->count is enough, it is needed to check if 225 * there are actual empty entries. 226 * Otherwise, and if "dentry + hint_famp->count" is also equal 227 * to "p_dir->size * dentries_per_clu", it means ENOSPC. 228 */ 229 if (dentry + hint_femp->count == total_entries && 230 num_entries > hint_femp->count) 231 return -ENOSPC; 232 233 hint_femp->eidx = EXFAT_HINT_NONE; 234 exfat_chain_dup(&clu, &hint_femp->cur); 235 } else { 236 exfat_chain_dup(&clu, p_dir); 237 dentry = 0; 238 } 239 240 while (dentry + num_entries < total_entries && 241 clu.dir != EXFAT_EOF_CLUSTER) { 242 i = dentry & (dentries_per_clu - 1); 243 244 ret = exfat_get_empty_dentry_set(es, sb, &clu, i, num_entries); 245 if (ret < 0) 246 return ret; 247 else if (ret == 0) 248 return dentry; 249 250 dentry += ret; 251 i += ret; 252 253 while (i >= dentries_per_clu) { 254 if (clu.flags == ALLOC_NO_FAT_CHAIN) { 255 if (--clu.size > 0) 256 clu.dir++; 257 else 258 clu.dir = EXFAT_EOF_CLUSTER; 259 } else { 260 if (exfat_get_next_cluster(sb, &clu.dir)) 261 return -EIO; 262 } 263 264 i -= dentries_per_clu; 265 } 266 } 267 268 hint_femp->eidx = dentry; 269 hint_femp->count = 0; 270 if (dentry == total_entries || clu.dir == EXFAT_EOF_CLUSTER) 271 exfat_chain_set(&hint_femp->cur, EXFAT_EOF_CLUSTER, 0, 272 clu.flags); 273 else 274 hint_femp->cur = clu; 275 276 return -ENOSPC; 277 } 278 279 static int exfat_check_max_dentries(struct inode *inode) 280 { 281 if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) { 282 /* 283 * exFAT spec allows a dir to grow up to 8388608(256MB) 284 * dentries 285 */ 286 return -ENOSPC; 287 } 288 return 0; 289 } 290 291 /* find empty directory entry. 292 * if there isn't any empty slot, expand cluster chain. 293 */ 294 static int exfat_find_empty_entry(struct inode *inode, 295 struct exfat_chain *p_dir, int num_entries, 296 struct exfat_entry_set_cache *es) 297 { 298 int dentry; 299 unsigned int ret, last_clu; 300 loff_t size = 0; 301 struct exfat_chain clu; 302 struct super_block *sb = inode->i_sb; 303 struct exfat_sb_info *sbi = EXFAT_SB(sb); 304 struct exfat_inode_info *ei = EXFAT_I(inode); 305 struct exfat_hint_femp hint_femp; 306 307 hint_femp.eidx = EXFAT_HINT_NONE; 308 309 if (ei->hint_femp.eidx != EXFAT_HINT_NONE) { 310 hint_femp = ei->hint_femp; 311 ei->hint_femp.eidx = EXFAT_HINT_NONE; 312 } 313 314 exfat_chain_set(p_dir, ei->start_clu, 315 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags); 316 317 while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir, 318 num_entries, es)) < 0) { 319 if (dentry == -EIO) 320 break; 321 322 if (exfat_check_max_dentries(inode)) 323 return -ENOSPC; 324 325 /* 326 * Allocate new cluster to this directory 327 */ 328 if (ei->start_clu != EXFAT_EOF_CLUSTER) { 329 /* we trust p_dir->size regardless of FAT type */ 330 if (exfat_find_last_cluster(sb, p_dir, &last_clu)) 331 return -EIO; 332 333 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags); 334 } else { 335 /* This directory is empty */ 336 exfat_chain_set(&clu, EXFAT_EOF_CLUSTER, 0, 337 ALLOC_NO_FAT_CHAIN); 338 } 339 340 /* allocate a cluster */ 341 ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode)); 342 if (ret) 343 return ret; 344 345 if (exfat_zeroed_cluster(inode, clu.dir)) 346 return -EIO; 347 348 if (ei->start_clu == EXFAT_EOF_CLUSTER) { 349 ei->start_clu = clu.dir; 350 p_dir->dir = clu.dir; 351 hint_femp.eidx = 0; 352 } 353 354 /* append to the FAT chain */ 355 if (clu.flags != p_dir->flags) { 356 /* no-fat-chain bit is disabled, 357 * so fat-chain should be synced with alloc-bitmap 358 */ 359 exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size); 360 p_dir->flags = ALLOC_FAT_CHAIN; 361 hint_femp.cur.flags = ALLOC_FAT_CHAIN; 362 } 363 364 if (clu.flags == ALLOC_FAT_CHAIN) 365 if (exfat_ent_set(sb, last_clu, clu.dir)) 366 return -EIO; 367 368 if (hint_femp.cur.dir == EXFAT_EOF_CLUSTER) 369 exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags); 370 371 hint_femp.count += sbi->dentries_per_clu; 372 373 hint_femp.cur.size++; 374 p_dir->size++; 375 size = EXFAT_CLU_TO_B(p_dir->size, sbi); 376 377 /* directory inode should be updated in here */ 378 i_size_write(inode, size); 379 ei->valid_size += sbi->cluster_size; 380 ei->flags = p_dir->flags; 381 inode->i_blocks += sbi->cluster_size >> 9; 382 } 383 384 return dentry; 385 } 386 387 /* 388 * Name Resolution Functions : 389 * Zero if it was successful; otherwise nonzero. 390 */ 391 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path, 392 struct exfat_uni_name *p_uniname, int lookup) 393 { 394 int namelen; 395 int lossy = NLS_NAME_NO_LOSSY; 396 struct super_block *sb = inode->i_sb; 397 int pathlen = strlen(path); 398 399 /* 400 * get the length of the pathname excluding 401 * trailing periods, if any. 402 */ 403 namelen = exfat_striptail_len(pathlen, path, false); 404 if (EXFAT_SB(sb)->options.keep_last_dots) { 405 /* 406 * Do not allow the creation of files with names 407 * ending with period(s). 408 */ 409 if (!lookup && (namelen < pathlen)) 410 return -EINVAL; 411 namelen = pathlen; 412 } 413 if (!namelen) 414 return -ENOENT; 415 if (pathlen > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE)) 416 return -ENAMETOOLONG; 417 418 /* 419 * strip all leading spaces : 420 * "MS windows 7" supports leading spaces. 421 * So we should skip this preprocessing for compatibility. 422 */ 423 424 /* file name conversion : 425 * If lookup case, we allow bad-name for compatibility. 426 */ 427 namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname, 428 &lossy); 429 if (namelen < 0) 430 return namelen; /* return error value */ 431 432 if ((lossy && !lookup) || !namelen) 433 return (lossy & NLS_NAME_OVERLEN) ? -ENAMETOOLONG : -EINVAL; 434 435 return 0; 436 } 437 438 static inline int exfat_resolve_path(struct inode *inode, 439 const unsigned char *path, struct exfat_uni_name *uni) 440 { 441 return __exfat_resolve_path(inode, path, uni, 0); 442 } 443 444 static inline int exfat_resolve_path_for_lookup(struct inode *inode, 445 const unsigned char *path, struct exfat_uni_name *uni) 446 { 447 return __exfat_resolve_path(inode, path, uni, 1); 448 } 449 450 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info) 451 { 452 return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff); 453 } 454 455 static int exfat_add_entry(struct inode *inode, const char *path, 456 unsigned int type, struct exfat_dir_entry *info) 457 { 458 int ret, dentry, num_entries; 459 struct super_block *sb = inode->i_sb; 460 struct exfat_sb_info *sbi = EXFAT_SB(sb); 461 struct exfat_uni_name uniname; 462 struct exfat_chain clu; 463 struct timespec64 ts = current_time(inode); 464 struct exfat_entry_set_cache es; 465 int clu_size = 0; 466 unsigned int start_clu = EXFAT_FREE_CLUSTER; 467 468 ret = exfat_resolve_path(inode, path, &uniname); 469 if (ret) 470 goto out; 471 472 num_entries = exfat_calc_num_entries(&uniname); 473 if (num_entries < 0) { 474 ret = num_entries; 475 goto out; 476 } 477 478 /* exfat_find_empty_entry must be called before alloc_cluster() */ 479 dentry = exfat_find_empty_entry(inode, &info->dir, num_entries, &es); 480 if (dentry < 0) { 481 ret = dentry; /* -EIO or -ENOSPC */ 482 goto out; 483 } 484 485 if (type == TYPE_DIR && !sbi->options.zero_size_dir) { 486 ret = exfat_alloc_new_dir(inode, &clu); 487 if (ret) { 488 exfat_put_dentry_set(&es, false); 489 goto out; 490 } 491 start_clu = clu.dir; 492 clu_size = sbi->cluster_size; 493 } 494 495 /* update the directory entry */ 496 /* fill the dos name directory entry information of the created file. 497 * the first cluster is not determined yet. (0) 498 */ 499 exfat_init_dir_entry(&es, type, start_clu, clu_size, &ts); 500 exfat_init_ext_entry(&es, num_entries, &uniname); 501 502 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 503 if (ret) 504 goto out; 505 506 info->entry = dentry; 507 info->flags = ALLOC_NO_FAT_CHAIN; 508 info->type = type; 509 510 if (type == TYPE_FILE) { 511 info->attr = EXFAT_ATTR_ARCHIVE; 512 info->start_clu = EXFAT_EOF_CLUSTER; 513 info->size = 0; 514 info->num_subdirs = 0; 515 } else { 516 info->attr = EXFAT_ATTR_SUBDIR; 517 if (sbi->options.zero_size_dir) 518 info->start_clu = EXFAT_EOF_CLUSTER; 519 else 520 info->start_clu = start_clu; 521 info->size = clu_size; 522 info->num_subdirs = EXFAT_MIN_SUBDIR; 523 } 524 info->valid_size = info->size; 525 526 memset(&info->crtime, 0, sizeof(info->crtime)); 527 memset(&info->mtime, 0, sizeof(info->mtime)); 528 memset(&info->atime, 0, sizeof(info->atime)); 529 out: 530 return ret; 531 } 532 533 static int exfat_create(struct mnt_idmap *idmap, struct inode *dir, 534 struct dentry *dentry, umode_t mode, bool excl) 535 { 536 struct super_block *sb = dir->i_sb; 537 struct inode *inode; 538 struct exfat_dir_entry info; 539 loff_t i_pos; 540 int err; 541 loff_t size = i_size_read(dir); 542 543 if (unlikely(exfat_forced_shutdown(sb))) 544 return -EIO; 545 546 mutex_lock(&EXFAT_SB(sb)->s_lock); 547 exfat_set_volume_dirty(sb); 548 err = exfat_add_entry(dir, dentry->d_name.name, TYPE_FILE, &info); 549 if (err) 550 goto unlock; 551 552 inode_inc_iversion(dir); 553 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 554 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 555 exfat_sync_inode(dir); 556 else 557 mark_inode_dirty(dir); 558 559 i_pos = exfat_make_i_pos(&info); 560 inode = exfat_build_inode(sb, &info, i_pos); 561 err = PTR_ERR_OR_ZERO(inode); 562 if (err) 563 goto unlock; 564 565 inode_inc_iversion(inode); 566 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 567 exfat_truncate_inode_atime(inode); 568 569 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 570 571 d_instantiate(dentry, inode); 572 unlock: 573 mutex_unlock(&EXFAT_SB(sb)->s_lock); 574 return err; 575 } 576 577 /* lookup a file */ 578 static int exfat_find(struct inode *dir, struct qstr *qname, 579 struct exfat_dir_entry *info) 580 { 581 int ret, dentry, count; 582 struct exfat_chain cdir; 583 struct exfat_uni_name uni_name; 584 struct super_block *sb = dir->i_sb; 585 struct exfat_sb_info *sbi = EXFAT_SB(sb); 586 struct exfat_inode_info *ei = EXFAT_I(dir); 587 struct exfat_dentry *ep, *ep2; 588 struct exfat_entry_set_cache es; 589 /* for optimized dir & entry to prevent long traverse of cluster chain */ 590 struct exfat_hint hint_opt; 591 592 if (qname->len == 0) 593 return -ENOENT; 594 595 /* check the validity of directory name in the given pathname */ 596 ret = exfat_resolve_path_for_lookup(dir, qname->name, &uni_name); 597 if (ret) 598 return ret; 599 600 exfat_chain_set(&cdir, ei->start_clu, 601 EXFAT_B_TO_CLU(i_size_read(dir), sbi), ei->flags); 602 603 /* check the validation of hint_stat and initialize it if required */ 604 if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) { 605 ei->hint_stat.clu = cdir.dir; 606 ei->hint_stat.eidx = 0; 607 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff); 608 ei->hint_femp.eidx = EXFAT_HINT_NONE; 609 } 610 611 /* search the file name for directories */ 612 dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name, &hint_opt); 613 if (dentry < 0) 614 return dentry; /* -error value */ 615 616 info->dir = cdir; 617 info->entry = dentry; 618 info->num_subdirs = 0; 619 620 /* adjust cdir to the optimized value */ 621 cdir.dir = hint_opt.clu; 622 if (cdir.flags & ALLOC_NO_FAT_CHAIN) 623 cdir.size -= dentry / sbi->dentries_per_clu; 624 dentry = hint_opt.eidx; 625 if (exfat_get_dentry_set(&es, sb, &cdir, dentry, ES_2_ENTRIES)) 626 return -EIO; 627 ep = exfat_get_dentry_cached(&es, ES_IDX_FILE); 628 ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM); 629 630 info->type = exfat_get_entry_type(ep); 631 info->attr = le16_to_cpu(ep->dentry.file.attr); 632 info->size = le64_to_cpu(ep2->dentry.stream.valid_size); 633 info->valid_size = le64_to_cpu(ep2->dentry.stream.valid_size); 634 info->size = le64_to_cpu(ep2->dentry.stream.size); 635 636 info->start_clu = le32_to_cpu(ep2->dentry.stream.start_clu); 637 if (!is_valid_cluster(sbi, info->start_clu) && info->size) { 638 exfat_warn(sb, "start_clu is invalid cluster(0x%x)", 639 info->start_clu); 640 info->size = 0; 641 info->valid_size = 0; 642 } 643 644 if (info->valid_size > info->size) { 645 exfat_warn(sb, "valid_size(%lld) is greater than size(%lld)", 646 info->valid_size, info->size); 647 info->valid_size = info->size; 648 } 649 650 if (info->size == 0) { 651 info->flags = ALLOC_NO_FAT_CHAIN; 652 info->start_clu = EXFAT_EOF_CLUSTER; 653 } else 654 info->flags = ep2->dentry.stream.flags; 655 656 exfat_get_entry_time(sbi, &info->crtime, 657 ep->dentry.file.create_tz, 658 ep->dentry.file.create_time, 659 ep->dentry.file.create_date, 660 ep->dentry.file.create_time_cs); 661 exfat_get_entry_time(sbi, &info->mtime, 662 ep->dentry.file.modify_tz, 663 ep->dentry.file.modify_time, 664 ep->dentry.file.modify_date, 665 ep->dentry.file.modify_time_cs); 666 exfat_get_entry_time(sbi, &info->atime, 667 ep->dentry.file.access_tz, 668 ep->dentry.file.access_time, 669 ep->dentry.file.access_date, 670 0); 671 exfat_put_dentry_set(&es, false); 672 673 if (ei->start_clu == EXFAT_FREE_CLUSTER) { 674 exfat_fs_error(sb, 675 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)", 676 i_size_read(dir), ei->dir.dir, ei->entry); 677 return -EIO; 678 } 679 680 if (info->type == TYPE_DIR) { 681 exfat_chain_set(&cdir, info->start_clu, 682 EXFAT_B_TO_CLU(info->size, sbi), info->flags); 683 count = exfat_count_dir_entries(sb, &cdir); 684 if (count < 0) 685 return -EIO; 686 687 info->num_subdirs = count + EXFAT_MIN_SUBDIR; 688 } 689 return 0; 690 } 691 692 static int exfat_d_anon_disconn(struct dentry *dentry) 693 { 694 return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED); 695 } 696 697 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry, 698 unsigned int flags) 699 { 700 struct super_block *sb = dir->i_sb; 701 struct inode *inode; 702 struct dentry *alias; 703 struct exfat_dir_entry info; 704 int err; 705 loff_t i_pos; 706 mode_t i_mode; 707 708 mutex_lock(&EXFAT_SB(sb)->s_lock); 709 err = exfat_find(dir, &dentry->d_name, &info); 710 if (err) { 711 if (err == -ENOENT) { 712 inode = NULL; 713 goto out; 714 } 715 goto unlock; 716 } 717 718 i_pos = exfat_make_i_pos(&info); 719 inode = exfat_build_inode(sb, &info, i_pos); 720 err = PTR_ERR_OR_ZERO(inode); 721 if (err) 722 goto unlock; 723 724 i_mode = inode->i_mode; 725 alias = d_find_alias(inode); 726 727 /* 728 * Checking "alias->d_parent == dentry->d_parent" to make sure 729 * FS is not corrupted (especially double linked dir). 730 */ 731 if (alias && alias->d_parent == dentry->d_parent && 732 !exfat_d_anon_disconn(alias)) { 733 734 /* 735 * Unhashed alias is able to exist because of revalidate() 736 * called by lookup_fast. You can easily make this status 737 * by calling create and lookup concurrently 738 * In such case, we reuse an alias instead of new dentry 739 */ 740 if (d_unhashed(alias)) { 741 WARN_ON(alias->d_name.hash_len != 742 dentry->d_name.hash_len); 743 exfat_info(sb, "rehashed a dentry(%p) in read lookup", 744 alias); 745 d_drop(dentry); 746 d_rehash(alias); 747 } else if (!S_ISDIR(i_mode)) { 748 /* 749 * This inode has non anonymous-DCACHE_DISCONNECTED 750 * dentry. This means, the user did ->lookup() by an 751 * another name (longname vs 8.3 alias of it) in past. 752 * 753 * Switch to new one for reason of locality if possible. 754 */ 755 d_move(alias, dentry); 756 } 757 iput(inode); 758 mutex_unlock(&EXFAT_SB(sb)->s_lock); 759 return alias; 760 } 761 dput(alias); 762 out: 763 mutex_unlock(&EXFAT_SB(sb)->s_lock); 764 if (!inode) 765 exfat_d_version_set(dentry, inode_query_iversion(dir)); 766 767 return d_splice_alias(inode, dentry); 768 unlock: 769 mutex_unlock(&EXFAT_SB(sb)->s_lock); 770 return ERR_PTR(err); 771 } 772 773 /* remove an entry, BUT don't truncate */ 774 static int exfat_unlink(struct inode *dir, struct dentry *dentry) 775 { 776 struct super_block *sb = dir->i_sb; 777 struct inode *inode = dentry->d_inode; 778 struct exfat_inode_info *ei = EXFAT_I(inode); 779 struct exfat_entry_set_cache es; 780 int err = 0; 781 782 if (unlikely(exfat_forced_shutdown(sb))) 783 return -EIO; 784 785 mutex_lock(&EXFAT_SB(sb)->s_lock); 786 if (ei->dir.dir == DIR_DELETED) { 787 exfat_err(sb, "abnormal access to deleted dentry"); 788 err = -ENOENT; 789 goto unlock; 790 } 791 792 err = exfat_get_dentry_set_by_ei(&es, sb, ei); 793 if (err) { 794 err = -EIO; 795 goto unlock; 796 } 797 798 exfat_set_volume_dirty(sb); 799 800 /* update the directory entry */ 801 exfat_remove_entries(inode, &es, ES_IDX_FILE); 802 803 err = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 804 if (err) 805 goto unlock; 806 807 /* This doesn't modify ei */ 808 ei->dir.dir = DIR_DELETED; 809 810 inode_inc_iversion(dir); 811 simple_inode_init_ts(dir); 812 exfat_truncate_inode_atime(dir); 813 mark_inode_dirty(dir); 814 815 clear_nlink(inode); 816 simple_inode_init_ts(inode); 817 exfat_truncate_inode_atime(inode); 818 exfat_unhash_inode(inode); 819 exfat_d_version_set(dentry, inode_query_iversion(dir)); 820 unlock: 821 mutex_unlock(&EXFAT_SB(sb)->s_lock); 822 return err; 823 } 824 825 static int exfat_mkdir(struct mnt_idmap *idmap, struct inode *dir, 826 struct dentry *dentry, umode_t mode) 827 { 828 struct super_block *sb = dir->i_sb; 829 struct inode *inode; 830 struct exfat_dir_entry info; 831 loff_t i_pos; 832 int err; 833 loff_t size = i_size_read(dir); 834 835 if (unlikely(exfat_forced_shutdown(sb))) 836 return -EIO; 837 838 mutex_lock(&EXFAT_SB(sb)->s_lock); 839 exfat_set_volume_dirty(sb); 840 err = exfat_add_entry(dir, dentry->d_name.name, TYPE_DIR, &info); 841 if (err) 842 goto unlock; 843 844 inode_inc_iversion(dir); 845 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 846 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 847 exfat_sync_inode(dir); 848 else 849 mark_inode_dirty(dir); 850 inc_nlink(dir); 851 852 i_pos = exfat_make_i_pos(&info); 853 inode = exfat_build_inode(sb, &info, i_pos); 854 err = PTR_ERR_OR_ZERO(inode); 855 if (err) 856 goto unlock; 857 858 inode_inc_iversion(inode); 859 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 860 exfat_truncate_inode_atime(inode); 861 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 862 863 d_instantiate(dentry, inode); 864 865 unlock: 866 mutex_unlock(&EXFAT_SB(sb)->s_lock); 867 return err; 868 } 869 870 static int exfat_check_dir_empty(struct super_block *sb, 871 struct exfat_chain *p_dir) 872 { 873 int i, dentries_per_clu; 874 unsigned int type; 875 struct exfat_chain clu; 876 struct exfat_dentry *ep; 877 struct exfat_sb_info *sbi = EXFAT_SB(sb); 878 struct buffer_head *bh; 879 880 dentries_per_clu = sbi->dentries_per_clu; 881 882 if (p_dir->dir == EXFAT_EOF_CLUSTER) 883 return 0; 884 885 exfat_chain_dup(&clu, p_dir); 886 887 while (clu.dir != EXFAT_EOF_CLUSTER) { 888 for (i = 0; i < dentries_per_clu; i++) { 889 ep = exfat_get_dentry(sb, &clu, i, &bh); 890 if (!ep) 891 return -EIO; 892 type = exfat_get_entry_type(ep); 893 brelse(bh); 894 if (type == TYPE_UNUSED) 895 return 0; 896 897 if (type != TYPE_FILE && type != TYPE_DIR) 898 continue; 899 900 return -ENOTEMPTY; 901 } 902 903 if (clu.flags == ALLOC_NO_FAT_CHAIN) { 904 if (--clu.size > 0) 905 clu.dir++; 906 else 907 clu.dir = EXFAT_EOF_CLUSTER; 908 } else { 909 if (exfat_get_next_cluster(sb, &(clu.dir))) 910 return -EIO; 911 } 912 } 913 914 return 0; 915 } 916 917 static int exfat_rmdir(struct inode *dir, struct dentry *dentry) 918 { 919 struct inode *inode = dentry->d_inode; 920 struct exfat_chain clu_to_free; 921 struct super_block *sb = inode->i_sb; 922 struct exfat_sb_info *sbi = EXFAT_SB(sb); 923 struct exfat_inode_info *ei = EXFAT_I(inode); 924 struct exfat_entry_set_cache es; 925 int err; 926 927 if (unlikely(exfat_forced_shutdown(sb))) 928 return -EIO; 929 930 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock); 931 932 if (ei->dir.dir == DIR_DELETED) { 933 exfat_err(sb, "abnormal access to deleted dentry"); 934 err = -ENOENT; 935 goto unlock; 936 } 937 938 exfat_chain_set(&clu_to_free, ei->start_clu, 939 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags); 940 941 err = exfat_check_dir_empty(sb, &clu_to_free); 942 if (err) { 943 if (err == -EIO) 944 exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)", 945 err); 946 goto unlock; 947 } 948 949 err = exfat_get_dentry_set_by_ei(&es, sb, ei); 950 if (err) { 951 err = -EIO; 952 goto unlock; 953 } 954 955 exfat_set_volume_dirty(sb); 956 957 exfat_remove_entries(inode, &es, ES_IDX_FILE); 958 959 err = exfat_put_dentry_set(&es, IS_DIRSYNC(dir)); 960 if (err) 961 goto unlock; 962 963 ei->dir.dir = DIR_DELETED; 964 965 inode_inc_iversion(dir); 966 simple_inode_init_ts(dir); 967 exfat_truncate_inode_atime(dir); 968 if (IS_DIRSYNC(dir)) 969 exfat_sync_inode(dir); 970 else 971 mark_inode_dirty(dir); 972 drop_nlink(dir); 973 974 clear_nlink(inode); 975 simple_inode_init_ts(inode); 976 exfat_truncate_inode_atime(inode); 977 exfat_unhash_inode(inode); 978 exfat_d_version_set(dentry, inode_query_iversion(dir)); 979 unlock: 980 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock); 981 return err; 982 } 983 984 static int exfat_rename_file(struct inode *parent_inode, 985 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei) 986 { 987 int ret, num_new_entries; 988 struct exfat_dentry *epold, *epnew; 989 struct super_block *sb = parent_inode->i_sb; 990 struct exfat_entry_set_cache old_es, new_es; 991 int sync = IS_DIRSYNC(parent_inode); 992 993 if (unlikely(exfat_forced_shutdown(sb))) 994 return -EIO; 995 996 num_new_entries = exfat_calc_num_entries(p_uniname); 997 if (num_new_entries < 0) 998 return num_new_entries; 999 1000 ret = exfat_get_dentry_set_by_ei(&old_es, sb, ei); 1001 if (ret) { 1002 ret = -EIO; 1003 return ret; 1004 } 1005 1006 epold = exfat_get_dentry_cached(&old_es, ES_IDX_FILE); 1007 1008 if (old_es.num_entries < num_new_entries) { 1009 int newentry; 1010 struct exfat_chain dir; 1011 1012 newentry = exfat_find_empty_entry(parent_inode, &dir, 1013 num_new_entries, &new_es); 1014 if (newentry < 0) { 1015 ret = newentry; /* -EIO or -ENOSPC */ 1016 goto put_old_es; 1017 } 1018 1019 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1020 *epnew = *epold; 1021 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1022 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1023 ei->attr |= EXFAT_ATTR_ARCHIVE; 1024 } 1025 1026 epold = exfat_get_dentry_cached(&old_es, ES_IDX_STREAM); 1027 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1028 *epnew = *epold; 1029 1030 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1031 1032 ret = exfat_put_dentry_set(&new_es, sync); 1033 if (ret) 1034 goto put_old_es; 1035 1036 exfat_remove_entries(parent_inode, &old_es, ES_IDX_FILE); 1037 ei->dir = dir; 1038 ei->entry = newentry; 1039 } else { 1040 if (exfat_get_entry_type(epold) == TYPE_FILE) { 1041 epold->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1042 ei->attr |= EXFAT_ATTR_ARCHIVE; 1043 } 1044 1045 exfat_remove_entries(parent_inode, &old_es, ES_IDX_FIRST_FILENAME + 1); 1046 exfat_init_ext_entry(&old_es, num_new_entries, p_uniname); 1047 } 1048 return exfat_put_dentry_set(&old_es, sync); 1049 1050 put_old_es: 1051 exfat_put_dentry_set(&old_es, false); 1052 return ret; 1053 } 1054 1055 static int exfat_move_file(struct inode *parent_inode, 1056 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei) 1057 { 1058 int ret, newentry, num_new_entries; 1059 struct exfat_dentry *epmov, *epnew; 1060 struct exfat_entry_set_cache mov_es, new_es; 1061 struct exfat_chain newdir; 1062 1063 num_new_entries = exfat_calc_num_entries(p_uniname); 1064 if (num_new_entries < 0) 1065 return num_new_entries; 1066 1067 ret = exfat_get_dentry_set_by_ei(&mov_es, parent_inode->i_sb, ei); 1068 if (ret) 1069 return -EIO; 1070 1071 newentry = exfat_find_empty_entry(parent_inode, &newdir, 1072 num_new_entries, &new_es); 1073 if (newentry < 0) { 1074 ret = newentry; /* -EIO or -ENOSPC */ 1075 goto put_mov_es; 1076 } 1077 1078 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_FILE); 1079 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1080 *epnew = *epmov; 1081 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1082 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1083 ei->attr |= EXFAT_ATTR_ARCHIVE; 1084 } 1085 1086 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_STREAM); 1087 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1088 *epnew = *epmov; 1089 1090 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1091 exfat_remove_entries(parent_inode, &mov_es, ES_IDX_FILE); 1092 1093 ei->dir = newdir; 1094 ei->entry = newentry; 1095 1096 ret = exfat_put_dentry_set(&new_es, IS_DIRSYNC(parent_inode)); 1097 if (ret) 1098 goto put_mov_es; 1099 1100 return exfat_put_dentry_set(&mov_es, IS_DIRSYNC(parent_inode)); 1101 1102 put_mov_es: 1103 exfat_put_dentry_set(&mov_es, false); 1104 1105 return ret; 1106 } 1107 1108 /* rename or move a old file into a new file */ 1109 static int __exfat_rename(struct inode *old_parent_inode, 1110 struct exfat_inode_info *ei, struct inode *new_parent_inode, 1111 struct dentry *new_dentry) 1112 { 1113 int ret; 1114 struct exfat_uni_name uni_name; 1115 struct super_block *sb = old_parent_inode->i_sb; 1116 struct exfat_sb_info *sbi = EXFAT_SB(sb); 1117 const unsigned char *new_path = new_dentry->d_name.name; 1118 struct inode *new_inode = new_dentry->d_inode; 1119 struct exfat_inode_info *new_ei = NULL; 1120 1121 /* check the validity of pointer parameters */ 1122 if (new_path == NULL || strlen(new_path) == 0) 1123 return -EINVAL; 1124 1125 if (ei->dir.dir == DIR_DELETED) { 1126 exfat_err(sb, "abnormal access to deleted source dentry"); 1127 return -ENOENT; 1128 } 1129 1130 /* check whether new dir is existing directory and empty */ 1131 if (new_inode) { 1132 ret = -EIO; 1133 new_ei = EXFAT_I(new_inode); 1134 1135 if (new_ei->dir.dir == DIR_DELETED) { 1136 exfat_err(sb, "abnormal access to deleted target dentry"); 1137 goto out; 1138 } 1139 1140 /* if new_inode exists, update ei */ 1141 if (S_ISDIR(new_inode->i_mode)) { 1142 struct exfat_chain new_clu; 1143 1144 new_clu.dir = new_ei->start_clu; 1145 new_clu.size = 1146 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1147 sbi); 1148 new_clu.flags = new_ei->flags; 1149 1150 ret = exfat_check_dir_empty(sb, &new_clu); 1151 if (ret) 1152 goto out; 1153 } 1154 } 1155 1156 /* check the validity of directory name in the given new pathname */ 1157 ret = exfat_resolve_path(new_parent_inode, new_path, &uni_name); 1158 if (ret) 1159 goto out; 1160 1161 exfat_set_volume_dirty(sb); 1162 1163 if (new_parent_inode == old_parent_inode) 1164 ret = exfat_rename_file(new_parent_inode, &uni_name, ei); 1165 else 1166 ret = exfat_move_file(new_parent_inode, &uni_name, ei); 1167 1168 if (!ret && new_inode) { 1169 struct exfat_entry_set_cache es; 1170 1171 /* delete entries of new_dir */ 1172 ret = exfat_get_dentry_set_by_ei(&es, sb, new_ei); 1173 if (ret) { 1174 ret = -EIO; 1175 goto del_out; 1176 } 1177 1178 exfat_remove_entries(new_inode, &es, ES_IDX_FILE); 1179 1180 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(new_inode)); 1181 if (ret) 1182 goto del_out; 1183 1184 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */ 1185 if (S_ISDIR(new_inode->i_mode) && 1186 new_ei->start_clu != EXFAT_EOF_CLUSTER) { 1187 /* new_ei, new_clu_to_free */ 1188 struct exfat_chain new_clu_to_free; 1189 1190 exfat_chain_set(&new_clu_to_free, new_ei->start_clu, 1191 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1192 sbi), new_ei->flags); 1193 1194 if (exfat_free_cluster(new_inode, &new_clu_to_free)) { 1195 /* just set I/O error only */ 1196 ret = -EIO; 1197 } 1198 1199 i_size_write(new_inode, 0); 1200 new_ei->valid_size = 0; 1201 new_ei->start_clu = EXFAT_EOF_CLUSTER; 1202 new_ei->flags = ALLOC_NO_FAT_CHAIN; 1203 } 1204 del_out: 1205 /* Update new_inode ei 1206 * Prevent syncing removed new_inode 1207 * (new_ei is already initialized above code ("if (new_inode)") 1208 */ 1209 new_ei->dir.dir = DIR_DELETED; 1210 } 1211 out: 1212 return ret; 1213 } 1214 1215 static int exfat_rename(struct mnt_idmap *idmap, 1216 struct inode *old_dir, struct dentry *old_dentry, 1217 struct inode *new_dir, struct dentry *new_dentry, 1218 unsigned int flags) 1219 { 1220 struct inode *old_inode, *new_inode; 1221 struct super_block *sb = old_dir->i_sb; 1222 loff_t i_pos; 1223 int err; 1224 loff_t size = i_size_read(new_dir); 1225 1226 /* 1227 * The VFS already checks for existence, so for local filesystems 1228 * the RENAME_NOREPLACE implementation is equivalent to plain rename. 1229 * Don't support any other flags 1230 */ 1231 if (flags & ~RENAME_NOREPLACE) 1232 return -EINVAL; 1233 1234 mutex_lock(&EXFAT_SB(sb)->s_lock); 1235 old_inode = old_dentry->d_inode; 1236 new_inode = new_dentry->d_inode; 1237 1238 err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry); 1239 if (err) 1240 goto unlock; 1241 1242 inode_inc_iversion(new_dir); 1243 simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry); 1244 EXFAT_I(new_dir)->i_crtime = current_time(new_dir); 1245 exfat_truncate_inode_atime(new_dir); 1246 if (IS_DIRSYNC(new_dir) && size != i_size_read(new_dir)) 1247 exfat_sync_inode(new_dir); 1248 else 1249 mark_inode_dirty(new_dir); 1250 1251 i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) | 1252 (EXFAT_I(old_inode)->entry & 0xffffffff); 1253 exfat_unhash_inode(old_inode); 1254 exfat_hash_inode(old_inode, i_pos); 1255 if (IS_DIRSYNC(new_dir)) 1256 exfat_sync_inode(old_inode); 1257 else 1258 mark_inode_dirty(old_inode); 1259 1260 if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) { 1261 drop_nlink(old_dir); 1262 if (!new_inode) 1263 inc_nlink(new_dir); 1264 } 1265 1266 inode_inc_iversion(old_dir); 1267 if (new_dir != old_dir) 1268 mark_inode_dirty(old_dir); 1269 1270 if (new_inode) { 1271 exfat_unhash_inode(new_inode); 1272 1273 /* skip drop_nlink if new_inode already has been dropped */ 1274 if (new_inode->i_nlink) { 1275 drop_nlink(new_inode); 1276 if (S_ISDIR(new_inode->i_mode)) 1277 drop_nlink(new_inode); 1278 } else { 1279 exfat_warn(sb, "abnormal access to an inode dropped"); 1280 WARN_ON(new_inode->i_nlink == 0); 1281 } 1282 EXFAT_I(new_inode)->i_crtime = current_time(new_inode); 1283 } 1284 1285 unlock: 1286 mutex_unlock(&EXFAT_SB(sb)->s_lock); 1287 return err; 1288 } 1289 1290 const struct inode_operations exfat_dir_inode_operations = { 1291 .create = exfat_create, 1292 .lookup = exfat_lookup, 1293 .unlink = exfat_unlink, 1294 .mkdir = exfat_mkdir, 1295 .rmdir = exfat_rmdir, 1296 .rename = exfat_rename, 1297 .setattr = exfat_setattr, 1298 .getattr = exfat_getattr, 1299 }; 1300