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 while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir, 315 num_entries, es)) < 0) { 316 if (dentry == -EIO) 317 break; 318 319 if (exfat_check_max_dentries(inode)) 320 return -ENOSPC; 321 322 /* 323 * Allocate new cluster to this directory 324 */ 325 if (ei->start_clu != EXFAT_EOF_CLUSTER) { 326 /* we trust p_dir->size regardless of FAT type */ 327 if (exfat_find_last_cluster(sb, p_dir, &last_clu)) 328 return -EIO; 329 330 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags); 331 } else { 332 /* This directory is empty */ 333 exfat_chain_set(&clu, EXFAT_EOF_CLUSTER, 0, 334 ALLOC_NO_FAT_CHAIN); 335 } 336 337 /* allocate a cluster */ 338 ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode)); 339 if (ret) 340 return ret; 341 342 if (exfat_zeroed_cluster(inode, clu.dir)) 343 return -EIO; 344 345 if (ei->start_clu == EXFAT_EOF_CLUSTER) { 346 ei->start_clu = clu.dir; 347 p_dir->dir = clu.dir; 348 } 349 350 /* append to the FAT chain */ 351 if (clu.flags != p_dir->flags) { 352 /* no-fat-chain bit is disabled, 353 * so fat-chain should be synced with alloc-bitmap 354 */ 355 exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size); 356 p_dir->flags = ALLOC_FAT_CHAIN; 357 hint_femp.cur.flags = ALLOC_FAT_CHAIN; 358 } 359 360 if (clu.flags == ALLOC_FAT_CHAIN) 361 if (exfat_ent_set(sb, last_clu, clu.dir)) 362 return -EIO; 363 364 if (hint_femp.cur.dir == EXFAT_EOF_CLUSTER) 365 exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags); 366 367 hint_femp.count += sbi->dentries_per_clu; 368 369 hint_femp.cur.size++; 370 p_dir->size++; 371 size = EXFAT_CLU_TO_B(p_dir->size, sbi); 372 373 /* directory inode should be updated in here */ 374 i_size_write(inode, size); 375 ei->i_size_aligned += sbi->cluster_size; 376 ei->valid_size += sbi->cluster_size; 377 ei->flags = p_dir->flags; 378 inode->i_blocks += sbi->cluster_size >> 9; 379 } 380 381 return dentry; 382 } 383 384 /* 385 * Name Resolution Functions : 386 * Zero if it was successful; otherwise nonzero. 387 */ 388 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path, 389 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname, 390 int lookup) 391 { 392 int namelen; 393 int lossy = NLS_NAME_NO_LOSSY; 394 struct super_block *sb = inode->i_sb; 395 struct exfat_sb_info *sbi = EXFAT_SB(sb); 396 struct exfat_inode_info *ei = EXFAT_I(inode); 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 exfat_chain_set(p_dir, ei->start_clu, 436 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags); 437 438 return 0; 439 } 440 441 static inline int exfat_resolve_path(struct inode *inode, 442 const unsigned char *path, struct exfat_chain *dir, 443 struct exfat_uni_name *uni) 444 { 445 return __exfat_resolve_path(inode, path, dir, uni, 0); 446 } 447 448 static inline int exfat_resolve_path_for_lookup(struct inode *inode, 449 const unsigned char *path, struct exfat_chain *dir, 450 struct exfat_uni_name *uni) 451 { 452 return __exfat_resolve_path(inode, path, dir, uni, 1); 453 } 454 455 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info) 456 { 457 return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff); 458 } 459 460 static int exfat_add_entry(struct inode *inode, const char *path, 461 struct exfat_chain *p_dir, unsigned int type, 462 struct exfat_dir_entry *info) 463 { 464 int ret, dentry, num_entries; 465 struct super_block *sb = inode->i_sb; 466 struct exfat_sb_info *sbi = EXFAT_SB(sb); 467 struct exfat_uni_name uniname; 468 struct exfat_chain clu; 469 struct timespec64 ts = current_time(inode); 470 struct exfat_entry_set_cache es; 471 int clu_size = 0; 472 unsigned int start_clu = EXFAT_FREE_CLUSTER; 473 474 ret = exfat_resolve_path(inode, path, p_dir, &uniname); 475 if (ret) 476 goto out; 477 478 num_entries = exfat_calc_num_entries(&uniname); 479 if (num_entries < 0) { 480 ret = num_entries; 481 goto out; 482 } 483 484 /* exfat_find_empty_entry must be called before alloc_cluster() */ 485 dentry = exfat_find_empty_entry(inode, p_dir, num_entries, &es); 486 if (dentry < 0) { 487 ret = dentry; /* -EIO or -ENOSPC */ 488 goto out; 489 } 490 491 if (type == TYPE_DIR && !sbi->options.zero_size_dir) { 492 ret = exfat_alloc_new_dir(inode, &clu); 493 if (ret) { 494 exfat_put_dentry_set(&es, false); 495 goto out; 496 } 497 start_clu = clu.dir; 498 clu_size = sbi->cluster_size; 499 } 500 501 /* update the directory entry */ 502 /* fill the dos name directory entry information of the created file. 503 * the first cluster is not determined yet. (0) 504 */ 505 exfat_init_dir_entry(&es, type, start_clu, clu_size, &ts); 506 exfat_init_ext_entry(&es, num_entries, &uniname); 507 508 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 509 if (ret) 510 goto out; 511 512 info->dir = *p_dir; 513 info->entry = dentry; 514 info->flags = ALLOC_NO_FAT_CHAIN; 515 info->type = type; 516 517 if (type == TYPE_FILE) { 518 info->attr = EXFAT_ATTR_ARCHIVE; 519 info->start_clu = EXFAT_EOF_CLUSTER; 520 info->size = 0; 521 info->num_subdirs = 0; 522 } else { 523 info->attr = EXFAT_ATTR_SUBDIR; 524 if (sbi->options.zero_size_dir) 525 info->start_clu = EXFAT_EOF_CLUSTER; 526 else 527 info->start_clu = start_clu; 528 info->size = clu_size; 529 info->num_subdirs = EXFAT_MIN_SUBDIR; 530 } 531 info->valid_size = info->size; 532 533 memset(&info->crtime, 0, sizeof(info->crtime)); 534 memset(&info->mtime, 0, sizeof(info->mtime)); 535 memset(&info->atime, 0, sizeof(info->atime)); 536 out: 537 return ret; 538 } 539 540 static int exfat_create(struct mnt_idmap *idmap, struct inode *dir, 541 struct dentry *dentry, umode_t mode, bool excl) 542 { 543 struct super_block *sb = dir->i_sb; 544 struct inode *inode; 545 struct exfat_chain cdir; 546 struct exfat_dir_entry info; 547 loff_t i_pos; 548 int err; 549 loff_t size = i_size_read(dir); 550 551 mutex_lock(&EXFAT_SB(sb)->s_lock); 552 exfat_set_volume_dirty(sb); 553 err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE, 554 &info); 555 if (err) 556 goto unlock; 557 558 inode_inc_iversion(dir); 559 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 560 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 561 exfat_sync_inode(dir); 562 else 563 mark_inode_dirty(dir); 564 565 i_pos = exfat_make_i_pos(&info); 566 inode = exfat_build_inode(sb, &info, i_pos); 567 err = PTR_ERR_OR_ZERO(inode); 568 if (err) 569 goto unlock; 570 571 inode_inc_iversion(inode); 572 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 573 exfat_truncate_inode_atime(inode); 574 575 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 576 577 d_instantiate(dentry, inode); 578 unlock: 579 mutex_unlock(&EXFAT_SB(sb)->s_lock); 580 return err; 581 } 582 583 /* lookup a file */ 584 static int exfat_find(struct inode *dir, struct qstr *qname, 585 struct exfat_dir_entry *info) 586 { 587 int ret, dentry, count; 588 struct exfat_chain cdir; 589 struct exfat_uni_name uni_name; 590 struct super_block *sb = dir->i_sb; 591 struct exfat_sb_info *sbi = EXFAT_SB(sb); 592 struct exfat_inode_info *ei = EXFAT_I(dir); 593 struct exfat_dentry *ep, *ep2; 594 struct exfat_entry_set_cache es; 595 /* for optimized dir & entry to prevent long traverse of cluster chain */ 596 struct exfat_hint hint_opt; 597 598 if (qname->len == 0) 599 return -ENOENT; 600 601 /* check the validity of directory name in the given pathname */ 602 ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name); 603 if (ret) 604 return ret; 605 606 /* check the validation of hint_stat and initialize it if required */ 607 if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) { 608 ei->hint_stat.clu = cdir.dir; 609 ei->hint_stat.eidx = 0; 610 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff); 611 ei->hint_femp.eidx = EXFAT_HINT_NONE; 612 } 613 614 /* search the file name for directories */ 615 dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name, &hint_opt); 616 if (dentry < 0) 617 return dentry; /* -error value */ 618 619 info->dir = cdir; 620 info->entry = dentry; 621 info->num_subdirs = 0; 622 623 /* adjust cdir to the optimized value */ 624 cdir.dir = hint_opt.clu; 625 if (cdir.flags & ALLOC_NO_FAT_CHAIN) 626 cdir.size -= dentry / sbi->dentries_per_clu; 627 dentry = hint_opt.eidx; 628 if (exfat_get_dentry_set(&es, sb, &cdir, dentry, ES_2_ENTRIES)) 629 return -EIO; 630 ep = exfat_get_dentry_cached(&es, ES_IDX_FILE); 631 ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM); 632 633 info->type = exfat_get_entry_type(ep); 634 info->attr = le16_to_cpu(ep->dentry.file.attr); 635 info->size = le64_to_cpu(ep2->dentry.stream.valid_size); 636 info->valid_size = le64_to_cpu(ep2->dentry.stream.valid_size); 637 info->size = le64_to_cpu(ep2->dentry.stream.size); 638 if (info->size == 0) { 639 info->flags = ALLOC_NO_FAT_CHAIN; 640 info->start_clu = EXFAT_EOF_CLUSTER; 641 } else { 642 info->flags = ep2->dentry.stream.flags; 643 info->start_clu = 644 le32_to_cpu(ep2->dentry.stream.start_clu); 645 } 646 647 exfat_get_entry_time(sbi, &info->crtime, 648 ep->dentry.file.create_tz, 649 ep->dentry.file.create_time, 650 ep->dentry.file.create_date, 651 ep->dentry.file.create_time_cs); 652 exfat_get_entry_time(sbi, &info->mtime, 653 ep->dentry.file.modify_tz, 654 ep->dentry.file.modify_time, 655 ep->dentry.file.modify_date, 656 ep->dentry.file.modify_time_cs); 657 exfat_get_entry_time(sbi, &info->atime, 658 ep->dentry.file.access_tz, 659 ep->dentry.file.access_time, 660 ep->dentry.file.access_date, 661 0); 662 exfat_put_dentry_set(&es, false); 663 664 if (ei->start_clu == EXFAT_FREE_CLUSTER) { 665 exfat_fs_error(sb, 666 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)", 667 i_size_read(dir), ei->dir.dir, ei->entry); 668 return -EIO; 669 } 670 671 if (info->type == TYPE_DIR) { 672 exfat_chain_set(&cdir, info->start_clu, 673 EXFAT_B_TO_CLU(info->size, sbi), info->flags); 674 count = exfat_count_dir_entries(sb, &cdir); 675 if (count < 0) 676 return -EIO; 677 678 info->num_subdirs = count + EXFAT_MIN_SUBDIR; 679 } 680 return 0; 681 } 682 683 static int exfat_d_anon_disconn(struct dentry *dentry) 684 { 685 return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED); 686 } 687 688 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry, 689 unsigned int flags) 690 { 691 struct super_block *sb = dir->i_sb; 692 struct inode *inode; 693 struct dentry *alias; 694 struct exfat_dir_entry info; 695 int err; 696 loff_t i_pos; 697 mode_t i_mode; 698 699 mutex_lock(&EXFAT_SB(sb)->s_lock); 700 err = exfat_find(dir, &dentry->d_name, &info); 701 if (err) { 702 if (err == -ENOENT) { 703 inode = NULL; 704 goto out; 705 } 706 goto unlock; 707 } 708 709 i_pos = exfat_make_i_pos(&info); 710 inode = exfat_build_inode(sb, &info, i_pos); 711 err = PTR_ERR_OR_ZERO(inode); 712 if (err) 713 goto unlock; 714 715 i_mode = inode->i_mode; 716 alias = d_find_alias(inode); 717 718 /* 719 * Checking "alias->d_parent == dentry->d_parent" to make sure 720 * FS is not corrupted (especially double linked dir). 721 */ 722 if (alias && alias->d_parent == dentry->d_parent && 723 !exfat_d_anon_disconn(alias)) { 724 725 /* 726 * Unhashed alias is able to exist because of revalidate() 727 * called by lookup_fast. You can easily make this status 728 * by calling create and lookup concurrently 729 * In such case, we reuse an alias instead of new dentry 730 */ 731 if (d_unhashed(alias)) { 732 WARN_ON(alias->d_name.hash_len != 733 dentry->d_name.hash_len); 734 exfat_info(sb, "rehashed a dentry(%p) in read lookup", 735 alias); 736 d_drop(dentry); 737 d_rehash(alias); 738 } else if (!S_ISDIR(i_mode)) { 739 /* 740 * This inode has non anonymous-DCACHE_DISCONNECTED 741 * dentry. This means, the user did ->lookup() by an 742 * another name (longname vs 8.3 alias of it) in past. 743 * 744 * Switch to new one for reason of locality if possible. 745 */ 746 d_move(alias, dentry); 747 } 748 iput(inode); 749 mutex_unlock(&EXFAT_SB(sb)->s_lock); 750 return alias; 751 } 752 dput(alias); 753 out: 754 mutex_unlock(&EXFAT_SB(sb)->s_lock); 755 if (!inode) 756 exfat_d_version_set(dentry, inode_query_iversion(dir)); 757 758 return d_splice_alias(inode, dentry); 759 unlock: 760 mutex_unlock(&EXFAT_SB(sb)->s_lock); 761 return ERR_PTR(err); 762 } 763 764 /* remove an entry, BUT don't truncate */ 765 static int exfat_unlink(struct inode *dir, struct dentry *dentry) 766 { 767 struct exfat_chain cdir; 768 struct super_block *sb = dir->i_sb; 769 struct inode *inode = dentry->d_inode; 770 struct exfat_inode_info *ei = EXFAT_I(inode); 771 struct exfat_entry_set_cache es; 772 int entry, err = 0; 773 774 mutex_lock(&EXFAT_SB(sb)->s_lock); 775 exfat_chain_dup(&cdir, &ei->dir); 776 entry = ei->entry; 777 if (ei->dir.dir == DIR_DELETED) { 778 exfat_err(sb, "abnormal access to deleted dentry"); 779 err = -ENOENT; 780 goto unlock; 781 } 782 783 err = exfat_get_dentry_set(&es, sb, &cdir, entry, ES_ALL_ENTRIES); 784 if (err) { 785 err = -EIO; 786 goto unlock; 787 } 788 789 exfat_set_volume_dirty(sb); 790 791 /* update the directory entry */ 792 exfat_remove_entries(inode, &es, ES_IDX_FILE); 793 794 err = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 795 if (err) 796 goto unlock; 797 798 /* This doesn't modify ei */ 799 ei->dir.dir = DIR_DELETED; 800 801 inode_inc_iversion(dir); 802 simple_inode_init_ts(dir); 803 exfat_truncate_inode_atime(dir); 804 mark_inode_dirty(dir); 805 806 clear_nlink(inode); 807 simple_inode_init_ts(inode); 808 exfat_truncate_inode_atime(inode); 809 exfat_unhash_inode(inode); 810 exfat_d_version_set(dentry, inode_query_iversion(dir)); 811 unlock: 812 mutex_unlock(&EXFAT_SB(sb)->s_lock); 813 return err; 814 } 815 816 static int exfat_mkdir(struct mnt_idmap *idmap, struct inode *dir, 817 struct dentry *dentry, umode_t mode) 818 { 819 struct super_block *sb = dir->i_sb; 820 struct inode *inode; 821 struct exfat_dir_entry info; 822 struct exfat_chain cdir; 823 loff_t i_pos; 824 int err; 825 loff_t size = i_size_read(dir); 826 827 mutex_lock(&EXFAT_SB(sb)->s_lock); 828 exfat_set_volume_dirty(sb); 829 err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR, 830 &info); 831 if (err) 832 goto unlock; 833 834 inode_inc_iversion(dir); 835 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 836 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 837 exfat_sync_inode(dir); 838 else 839 mark_inode_dirty(dir); 840 inc_nlink(dir); 841 842 i_pos = exfat_make_i_pos(&info); 843 inode = exfat_build_inode(sb, &info, i_pos); 844 err = PTR_ERR_OR_ZERO(inode); 845 if (err) 846 goto unlock; 847 848 inode_inc_iversion(inode); 849 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 850 exfat_truncate_inode_atime(inode); 851 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 852 853 d_instantiate(dentry, inode); 854 855 unlock: 856 mutex_unlock(&EXFAT_SB(sb)->s_lock); 857 return err; 858 } 859 860 static int exfat_check_dir_empty(struct super_block *sb, 861 struct exfat_chain *p_dir) 862 { 863 int i, dentries_per_clu; 864 unsigned int type; 865 struct exfat_chain clu; 866 struct exfat_dentry *ep; 867 struct exfat_sb_info *sbi = EXFAT_SB(sb); 868 struct buffer_head *bh; 869 870 dentries_per_clu = sbi->dentries_per_clu; 871 872 if (p_dir->dir == EXFAT_EOF_CLUSTER) 873 return 0; 874 875 exfat_chain_dup(&clu, p_dir); 876 877 while (clu.dir != EXFAT_EOF_CLUSTER) { 878 for (i = 0; i < dentries_per_clu; i++) { 879 ep = exfat_get_dentry(sb, &clu, i, &bh); 880 if (!ep) 881 return -EIO; 882 type = exfat_get_entry_type(ep); 883 brelse(bh); 884 if (type == TYPE_UNUSED) 885 return 0; 886 887 if (type != TYPE_FILE && type != TYPE_DIR) 888 continue; 889 890 return -ENOTEMPTY; 891 } 892 893 if (clu.flags == ALLOC_NO_FAT_CHAIN) { 894 if (--clu.size > 0) 895 clu.dir++; 896 else 897 clu.dir = EXFAT_EOF_CLUSTER; 898 } else { 899 if (exfat_get_next_cluster(sb, &(clu.dir))) 900 return -EIO; 901 } 902 } 903 904 return 0; 905 } 906 907 static int exfat_rmdir(struct inode *dir, struct dentry *dentry) 908 { 909 struct inode *inode = dentry->d_inode; 910 struct exfat_chain cdir, clu_to_free; 911 struct super_block *sb = inode->i_sb; 912 struct exfat_sb_info *sbi = EXFAT_SB(sb); 913 struct exfat_inode_info *ei = EXFAT_I(inode); 914 struct exfat_entry_set_cache es; 915 int entry, err; 916 917 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock); 918 919 exfat_chain_dup(&cdir, &ei->dir); 920 entry = ei->entry; 921 922 if (ei->dir.dir == DIR_DELETED) { 923 exfat_err(sb, "abnormal access to deleted dentry"); 924 err = -ENOENT; 925 goto unlock; 926 } 927 928 exfat_chain_set(&clu_to_free, ei->start_clu, 929 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags); 930 931 err = exfat_check_dir_empty(sb, &clu_to_free); 932 if (err) { 933 if (err == -EIO) 934 exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)", 935 err); 936 goto unlock; 937 } 938 939 err = exfat_get_dentry_set(&es, sb, &cdir, entry, ES_ALL_ENTRIES); 940 if (err) { 941 err = -EIO; 942 goto unlock; 943 } 944 945 exfat_set_volume_dirty(sb); 946 947 exfat_remove_entries(inode, &es, ES_IDX_FILE); 948 949 err = exfat_put_dentry_set(&es, IS_DIRSYNC(dir)); 950 if (err) 951 goto unlock; 952 953 ei->dir.dir = DIR_DELETED; 954 955 inode_inc_iversion(dir); 956 simple_inode_init_ts(dir); 957 exfat_truncate_inode_atime(dir); 958 if (IS_DIRSYNC(dir)) 959 exfat_sync_inode(dir); 960 else 961 mark_inode_dirty(dir); 962 drop_nlink(dir); 963 964 clear_nlink(inode); 965 simple_inode_init_ts(inode); 966 exfat_truncate_inode_atime(inode); 967 exfat_unhash_inode(inode); 968 exfat_d_version_set(dentry, inode_query_iversion(dir)); 969 unlock: 970 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock); 971 return err; 972 } 973 974 static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir, 975 int oldentry, struct exfat_uni_name *p_uniname, 976 struct exfat_inode_info *ei) 977 { 978 int ret, num_new_entries; 979 struct exfat_dentry *epold, *epnew; 980 struct super_block *sb = inode->i_sb; 981 struct exfat_entry_set_cache old_es, new_es; 982 int sync = IS_DIRSYNC(inode); 983 984 num_new_entries = exfat_calc_num_entries(p_uniname); 985 if (num_new_entries < 0) 986 return num_new_entries; 987 988 ret = exfat_get_dentry_set(&old_es, sb, p_dir, oldentry, ES_ALL_ENTRIES); 989 if (ret) { 990 ret = -EIO; 991 return ret; 992 } 993 994 epold = exfat_get_dentry_cached(&old_es, ES_IDX_FILE); 995 996 if (old_es.num_entries < num_new_entries) { 997 int newentry; 998 999 newentry = exfat_find_empty_entry(inode, p_dir, num_new_entries, 1000 &new_es); 1001 if (newentry < 0) { 1002 ret = newentry; /* -EIO or -ENOSPC */ 1003 goto put_old_es; 1004 } 1005 1006 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1007 *epnew = *epold; 1008 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1009 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1010 ei->attr |= EXFAT_ATTR_ARCHIVE; 1011 } 1012 1013 epold = exfat_get_dentry_cached(&old_es, ES_IDX_STREAM); 1014 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1015 *epnew = *epold; 1016 1017 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1018 1019 ret = exfat_put_dentry_set(&new_es, sync); 1020 if (ret) 1021 goto put_old_es; 1022 1023 exfat_remove_entries(inode, &old_es, ES_IDX_FILE); 1024 ei->dir = *p_dir; 1025 ei->entry = newentry; 1026 } else { 1027 if (exfat_get_entry_type(epold) == TYPE_FILE) { 1028 epold->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1029 ei->attr |= EXFAT_ATTR_ARCHIVE; 1030 } 1031 1032 exfat_remove_entries(inode, &old_es, ES_IDX_FIRST_FILENAME + 1); 1033 exfat_init_ext_entry(&old_es, num_new_entries, p_uniname); 1034 } 1035 return exfat_put_dentry_set(&old_es, sync); 1036 1037 put_old_es: 1038 exfat_put_dentry_set(&old_es, false); 1039 return ret; 1040 } 1041 1042 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir, 1043 int oldentry, struct exfat_chain *p_newdir, 1044 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei) 1045 { 1046 int ret, newentry, num_new_entries; 1047 struct exfat_dentry *epmov, *epnew; 1048 struct super_block *sb = inode->i_sb; 1049 struct exfat_entry_set_cache mov_es, new_es; 1050 1051 num_new_entries = exfat_calc_num_entries(p_uniname); 1052 if (num_new_entries < 0) 1053 return num_new_entries; 1054 1055 ret = exfat_get_dentry_set(&mov_es, sb, p_olddir, oldentry, 1056 ES_ALL_ENTRIES); 1057 if (ret) 1058 return -EIO; 1059 1060 newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries, 1061 &new_es); 1062 if (newentry < 0) { 1063 ret = newentry; /* -EIO or -ENOSPC */ 1064 goto put_mov_es; 1065 } 1066 1067 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_FILE); 1068 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1069 *epnew = *epmov; 1070 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1071 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1072 ei->attr |= EXFAT_ATTR_ARCHIVE; 1073 } 1074 1075 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_STREAM); 1076 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1077 *epnew = *epmov; 1078 1079 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1080 exfat_remove_entries(inode, &mov_es, ES_IDX_FILE); 1081 1082 exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size, 1083 p_newdir->flags); 1084 1085 ei->entry = newentry; 1086 1087 ret = exfat_put_dentry_set(&new_es, IS_DIRSYNC(inode)); 1088 if (ret) 1089 goto put_mov_es; 1090 1091 return exfat_put_dentry_set(&mov_es, IS_DIRSYNC(inode)); 1092 1093 put_mov_es: 1094 exfat_put_dentry_set(&mov_es, false); 1095 1096 return ret; 1097 } 1098 1099 /* rename or move a old file into a new file */ 1100 static int __exfat_rename(struct inode *old_parent_inode, 1101 struct exfat_inode_info *ei, struct inode *new_parent_inode, 1102 struct dentry *new_dentry) 1103 { 1104 int ret; 1105 int dentry; 1106 struct exfat_chain olddir, newdir; 1107 struct exfat_chain *p_dir = NULL; 1108 struct exfat_uni_name uni_name; 1109 struct exfat_dentry *ep; 1110 struct super_block *sb = old_parent_inode->i_sb; 1111 struct exfat_sb_info *sbi = EXFAT_SB(sb); 1112 const unsigned char *new_path = new_dentry->d_name.name; 1113 struct inode *new_inode = new_dentry->d_inode; 1114 struct exfat_inode_info *new_ei = NULL; 1115 unsigned int new_entry_type = TYPE_UNUSED; 1116 int new_entry = 0; 1117 struct buffer_head *new_bh = NULL; 1118 1119 /* check the validity of pointer parameters */ 1120 if (new_path == NULL || strlen(new_path) == 0) 1121 return -EINVAL; 1122 1123 if (ei->dir.dir == DIR_DELETED) { 1124 exfat_err(sb, "abnormal access to deleted source dentry"); 1125 return -ENOENT; 1126 } 1127 1128 exfat_chain_set(&olddir, EXFAT_I(old_parent_inode)->start_clu, 1129 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(old_parent_inode), sbi), 1130 EXFAT_I(old_parent_inode)->flags); 1131 dentry = ei->entry; 1132 1133 /* check whether new dir is existing directory and empty */ 1134 if (new_inode) { 1135 ret = -EIO; 1136 new_ei = EXFAT_I(new_inode); 1137 1138 if (new_ei->dir.dir == DIR_DELETED) { 1139 exfat_err(sb, "abnormal access to deleted target dentry"); 1140 goto out; 1141 } 1142 1143 p_dir = &(new_ei->dir); 1144 new_entry = new_ei->entry; 1145 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh); 1146 if (!ep) 1147 goto out; 1148 1149 new_entry_type = exfat_get_entry_type(ep); 1150 brelse(new_bh); 1151 1152 /* if new_inode exists, update ei */ 1153 if (new_entry_type == TYPE_DIR) { 1154 struct exfat_chain new_clu; 1155 1156 new_clu.dir = new_ei->start_clu; 1157 new_clu.size = 1158 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1159 sbi); 1160 new_clu.flags = new_ei->flags; 1161 1162 ret = exfat_check_dir_empty(sb, &new_clu); 1163 if (ret) 1164 goto out; 1165 } 1166 } 1167 1168 /* check the validity of directory name in the given new pathname */ 1169 ret = exfat_resolve_path(new_parent_inode, new_path, &newdir, 1170 &uni_name); 1171 if (ret) 1172 goto out; 1173 1174 exfat_set_volume_dirty(sb); 1175 1176 if (olddir.dir == newdir.dir) 1177 ret = exfat_rename_file(new_parent_inode, &olddir, dentry, 1178 &uni_name, ei); 1179 else 1180 ret = exfat_move_file(new_parent_inode, &olddir, dentry, 1181 &newdir, &uni_name, ei); 1182 1183 if (!ret && new_inode) { 1184 struct exfat_entry_set_cache es; 1185 1186 /* delete entries of new_dir */ 1187 ret = exfat_get_dentry_set(&es, sb, p_dir, new_entry, 1188 ES_ALL_ENTRIES); 1189 if (ret) { 1190 ret = -EIO; 1191 goto del_out; 1192 } 1193 1194 exfat_remove_entries(new_inode, &es, ES_IDX_FILE); 1195 1196 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(new_inode)); 1197 if (ret) 1198 goto del_out; 1199 1200 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */ 1201 if (new_entry_type == TYPE_DIR && 1202 new_ei->start_clu != EXFAT_EOF_CLUSTER) { 1203 /* new_ei, new_clu_to_free */ 1204 struct exfat_chain new_clu_to_free; 1205 1206 exfat_chain_set(&new_clu_to_free, new_ei->start_clu, 1207 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1208 sbi), new_ei->flags); 1209 1210 if (exfat_free_cluster(new_inode, &new_clu_to_free)) { 1211 /* just set I/O error only */ 1212 ret = -EIO; 1213 } 1214 1215 i_size_write(new_inode, 0); 1216 new_ei->valid_size = 0; 1217 new_ei->start_clu = EXFAT_EOF_CLUSTER; 1218 new_ei->flags = ALLOC_NO_FAT_CHAIN; 1219 } 1220 del_out: 1221 /* Update new_inode ei 1222 * Prevent syncing removed new_inode 1223 * (new_ei is already initialized above code ("if (new_inode)") 1224 */ 1225 new_ei->dir.dir = DIR_DELETED; 1226 } 1227 out: 1228 return ret; 1229 } 1230 1231 static int exfat_rename(struct mnt_idmap *idmap, 1232 struct inode *old_dir, struct dentry *old_dentry, 1233 struct inode *new_dir, struct dentry *new_dentry, 1234 unsigned int flags) 1235 { 1236 struct inode *old_inode, *new_inode; 1237 struct super_block *sb = old_dir->i_sb; 1238 loff_t i_pos; 1239 int err; 1240 loff_t size = i_size_read(new_dir); 1241 1242 /* 1243 * The VFS already checks for existence, so for local filesystems 1244 * the RENAME_NOREPLACE implementation is equivalent to plain rename. 1245 * Don't support any other flags 1246 */ 1247 if (flags & ~RENAME_NOREPLACE) 1248 return -EINVAL; 1249 1250 mutex_lock(&EXFAT_SB(sb)->s_lock); 1251 old_inode = old_dentry->d_inode; 1252 new_inode = new_dentry->d_inode; 1253 1254 err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry); 1255 if (err) 1256 goto unlock; 1257 1258 inode_inc_iversion(new_dir); 1259 simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry); 1260 EXFAT_I(new_dir)->i_crtime = current_time(new_dir); 1261 exfat_truncate_inode_atime(new_dir); 1262 if (IS_DIRSYNC(new_dir) && size != i_size_read(new_dir)) 1263 exfat_sync_inode(new_dir); 1264 else 1265 mark_inode_dirty(new_dir); 1266 1267 i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) | 1268 (EXFAT_I(old_inode)->entry & 0xffffffff); 1269 exfat_unhash_inode(old_inode); 1270 exfat_hash_inode(old_inode, i_pos); 1271 if (IS_DIRSYNC(new_dir)) 1272 exfat_sync_inode(old_inode); 1273 else 1274 mark_inode_dirty(old_inode); 1275 1276 if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) { 1277 drop_nlink(old_dir); 1278 if (!new_inode) 1279 inc_nlink(new_dir); 1280 } 1281 1282 inode_inc_iversion(old_dir); 1283 if (new_dir != old_dir) 1284 mark_inode_dirty(old_dir); 1285 1286 if (new_inode) { 1287 exfat_unhash_inode(new_inode); 1288 1289 /* skip drop_nlink if new_inode already has been dropped */ 1290 if (new_inode->i_nlink) { 1291 drop_nlink(new_inode); 1292 if (S_ISDIR(new_inode->i_mode)) 1293 drop_nlink(new_inode); 1294 } else { 1295 exfat_warn(sb, "abnormal access to an inode dropped"); 1296 WARN_ON(new_inode->i_nlink == 0); 1297 } 1298 EXFAT_I(new_inode)->i_crtime = current_time(new_inode); 1299 } 1300 1301 unlock: 1302 mutex_unlock(&EXFAT_SB(sb)->s_lock); 1303 return err; 1304 } 1305 1306 const struct inode_operations exfat_dir_inode_operations = { 1307 .create = exfat_create, 1308 .lookup = exfat_lookup, 1309 .unlink = exfat_unlink, 1310 .mkdir = exfat_mkdir, 1311 .rmdir = exfat_rmdir, 1312 .rename = exfat_rename, 1313 .setattr = exfat_setattr, 1314 .getattr = exfat_getattr, 1315 }; 1316