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 inode *dir, const struct qstr *name, 35 struct dentry *dentry, unsigned int flags) 36 { 37 if (flags & LOOKUP_RCU) 38 return -ECHILD; 39 40 /* 41 * This is not negative dentry. Always valid. 42 * 43 * Note, rename() to existing directory entry will have ->d_inode, and 44 * will use existing name which isn't specified name by user. 45 * 46 * We may be able to drop this positive dentry here. But dropping 47 * positive dentry isn't good idea. So it's unsupported like 48 * rename("filename", "FILENAME") for now. 49 */ 50 if (d_really_is_positive(dentry)) 51 return 1; 52 53 /* 54 * Drop the negative dentry, in order to make sure to use the case 55 * sensitive name which is specified by user if this is for creation. 56 */ 57 if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET)) 58 return 0; 59 60 return inode_eq_iversion(dir, exfat_d_version(dentry)); 61 } 62 63 /* returns the length of a struct qstr, ignoring trailing dots if necessary */ 64 static unsigned int exfat_striptail_len(unsigned int len, const char *name, 65 bool keep_last_dots) 66 { 67 if (!keep_last_dots) { 68 while (len && name[len - 1] == '.') 69 len--; 70 } 71 return len; 72 } 73 74 /* 75 * Compute the hash for the exfat name corresponding to the dentry. If the name 76 * is invalid, we leave the hash code unchanged so that the existing dentry can 77 * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate. 78 */ 79 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr) 80 { 81 struct super_block *sb = dentry->d_sb; 82 struct nls_table *t = EXFAT_SB(sb)->nls_io; 83 const unsigned char *name = qstr->name; 84 unsigned int len = exfat_striptail_len(qstr->len, qstr->name, 85 EXFAT_SB(sb)->options.keep_last_dots); 86 unsigned long hash = init_name_hash(dentry); 87 int i, charlen; 88 wchar_t c; 89 90 for (i = 0; i < len; i += charlen) { 91 charlen = t->char2uni(&name[i], len - i, &c); 92 if (charlen < 0) 93 return charlen; 94 hash = partial_name_hash(exfat_toupper(sb, c), hash); 95 } 96 97 qstr->hash = end_name_hash(hash); 98 return 0; 99 } 100 101 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len, 102 const char *str, const struct qstr *name) 103 { 104 struct super_block *sb = dentry->d_sb; 105 struct nls_table *t = EXFAT_SB(sb)->nls_io; 106 unsigned int alen = exfat_striptail_len(name->len, name->name, 107 EXFAT_SB(sb)->options.keep_last_dots); 108 unsigned int blen = exfat_striptail_len(len, str, 109 EXFAT_SB(sb)->options.keep_last_dots); 110 wchar_t c1, c2; 111 int charlen, i; 112 113 if (alen != blen) 114 return 1; 115 116 for (i = 0; i < len; i += charlen) { 117 charlen = t->char2uni(&name->name[i], alen - i, &c1); 118 if (charlen < 0) 119 return 1; 120 if (charlen != t->char2uni(&str[i], blen - i, &c2)) 121 return 1; 122 123 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2)) 124 return 1; 125 } 126 127 return 0; 128 } 129 130 const struct dentry_operations exfat_dentry_ops = { 131 .d_revalidate = exfat_d_revalidate, 132 .d_hash = exfat_d_hash, 133 .d_compare = exfat_d_cmp, 134 }; 135 136 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr) 137 { 138 struct super_block *sb = dentry->d_sb; 139 const unsigned char *name = qstr->name; 140 unsigned int len = exfat_striptail_len(qstr->len, qstr->name, 141 EXFAT_SB(sb)->options.keep_last_dots); 142 unsigned long hash = init_name_hash(dentry); 143 int i, charlen; 144 unicode_t u; 145 146 for (i = 0; i < len; i += charlen) { 147 charlen = utf8_to_utf32(&name[i], len - i, &u); 148 if (charlen < 0) 149 return charlen; 150 151 /* 152 * exfat_toupper() works only for code points up to the U+FFFF. 153 */ 154 hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u, 155 hash); 156 } 157 158 qstr->hash = end_name_hash(hash); 159 return 0; 160 } 161 162 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len, 163 const char *str, const struct qstr *name) 164 { 165 struct super_block *sb = dentry->d_sb; 166 unsigned int alen = exfat_striptail_len(name->len, name->name, 167 EXFAT_SB(sb)->options.keep_last_dots); 168 unsigned int blen = exfat_striptail_len(len, str, 169 EXFAT_SB(sb)->options.keep_last_dots); 170 171 unicode_t u_a, u_b; 172 int charlen, i; 173 174 if (alen != blen) 175 return 1; 176 177 for (i = 0; i < alen; i += charlen) { 178 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a); 179 if (charlen < 0) 180 return 1; 181 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b)) 182 return 1; 183 184 if (u_a <= 0xFFFF && u_b <= 0xFFFF) { 185 if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b)) 186 return 1; 187 } else { 188 if (u_a != u_b) 189 return 1; 190 } 191 } 192 193 return 0; 194 } 195 196 const struct dentry_operations exfat_utf8_dentry_ops = { 197 .d_revalidate = exfat_d_revalidate, 198 .d_hash = exfat_utf8_d_hash, 199 .d_compare = exfat_utf8_d_cmp, 200 }; 201 202 /* search EMPTY CONTINUOUS "num_entries" entries */ 203 static int exfat_search_empty_slot(struct super_block *sb, 204 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir, 205 int num_entries, struct exfat_entry_set_cache *es) 206 { 207 int i, dentry, ret; 208 int dentries_per_clu; 209 struct exfat_chain clu; 210 struct exfat_sb_info *sbi = EXFAT_SB(sb); 211 int total_entries = EXFAT_CLU_TO_DEN(p_dir->size, sbi); 212 213 dentries_per_clu = sbi->dentries_per_clu; 214 215 if (hint_femp->eidx != EXFAT_HINT_NONE) { 216 dentry = hint_femp->eidx; 217 218 /* 219 * If hint_femp->count is enough, it is needed to check if 220 * there are actual empty entries. 221 * Otherwise, and if "dentry + hint_famp->count" is also equal 222 * to "p_dir->size * dentries_per_clu", it means ENOSPC. 223 */ 224 if (dentry + hint_femp->count == total_entries && 225 num_entries > hint_femp->count) 226 return -ENOSPC; 227 228 hint_femp->eidx = EXFAT_HINT_NONE; 229 exfat_chain_dup(&clu, &hint_femp->cur); 230 } else { 231 exfat_chain_dup(&clu, p_dir); 232 dentry = 0; 233 } 234 235 while (dentry + num_entries <= total_entries && 236 clu.dir != EXFAT_EOF_CLUSTER) { 237 i = dentry & (dentries_per_clu - 1); 238 239 ret = exfat_get_empty_dentry_set(es, sb, &clu, i, num_entries); 240 if (ret < 0) 241 return ret; 242 else if (ret == 0) 243 return dentry; 244 245 dentry += ret; 246 i += ret; 247 248 while (i >= dentries_per_clu) { 249 if (clu.flags == ALLOC_NO_FAT_CHAIN) { 250 if (--clu.size > 0) 251 clu.dir++; 252 else 253 clu.dir = EXFAT_EOF_CLUSTER; 254 } else { 255 if (exfat_get_next_cluster(sb, &clu.dir)) 256 return -EIO; 257 } 258 259 i -= dentries_per_clu; 260 } 261 } 262 263 hint_femp->eidx = dentry; 264 hint_femp->count = 0; 265 if (dentry == total_entries || clu.dir == EXFAT_EOF_CLUSTER) 266 exfat_chain_set(&hint_femp->cur, EXFAT_EOF_CLUSTER, 0, 267 clu.flags); 268 else 269 hint_femp->cur = clu; 270 271 return -ENOSPC; 272 } 273 274 static int exfat_check_max_dentries(struct inode *inode) 275 { 276 if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) { 277 /* 278 * exFAT spec allows a dir to grow up to 8388608(256MB) 279 * dentries 280 */ 281 return -ENOSPC; 282 } 283 return 0; 284 } 285 286 /* 287 * Find an empty directory entry set. 288 * 289 * If there isn't any empty slot, expand cluster chain. 290 * 291 * in: 292 * inode: inode of the parent directory 293 * num_entries: specifies how many dentries in the empty directory entry set 294 * 295 * out: 296 * p_dir: the cluster where the empty directory entry set is located 297 * es: The found empty directory entry set 298 * 299 * return: 300 * the directory entry index in p_dir is returned on succeeds 301 * -error code is returned on failure 302 */ 303 int exfat_find_empty_entry(struct inode *inode, 304 struct exfat_chain *p_dir, int num_entries, 305 struct exfat_entry_set_cache *es) 306 { 307 int dentry; 308 unsigned int ret, last_clu; 309 loff_t size = 0; 310 struct exfat_chain clu; 311 struct super_block *sb = inode->i_sb; 312 struct exfat_sb_info *sbi = EXFAT_SB(sb); 313 struct exfat_inode_info *ei = EXFAT_I(inode); 314 struct exfat_hint_femp hint_femp; 315 316 hint_femp.eidx = EXFAT_HINT_NONE; 317 318 if (ei->hint_femp.eidx != EXFAT_HINT_NONE) { 319 hint_femp = ei->hint_femp; 320 ei->hint_femp.eidx = EXFAT_HINT_NONE; 321 } 322 323 exfat_chain_set(p_dir, ei->start_clu, 324 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags); 325 326 while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir, 327 num_entries, es)) < 0) { 328 if (dentry != -ENOSPC) 329 return dentry; 330 331 if (exfat_check_max_dentries(inode)) 332 return -ENOSPC; 333 334 /* 335 * Allocate new cluster to this directory 336 */ 337 if (ei->start_clu != EXFAT_EOF_CLUSTER) { 338 /* we trust p_dir->size regardless of FAT type */ 339 if (exfat_find_last_cluster(sb, p_dir, &last_clu)) 340 return -EIO; 341 342 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags); 343 } else { 344 /* This directory is empty */ 345 exfat_chain_set(&clu, EXFAT_EOF_CLUSTER, 0, 346 ALLOC_NO_FAT_CHAIN); 347 } 348 349 /* allocate a cluster */ 350 ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode)); 351 if (ret) 352 return ret; 353 354 if (exfat_zeroed_cluster(inode, clu.dir)) 355 return -EIO; 356 357 if (ei->start_clu == EXFAT_EOF_CLUSTER) { 358 ei->start_clu = clu.dir; 359 p_dir->dir = clu.dir; 360 hint_femp.eidx = 0; 361 } 362 363 /* append to the FAT chain */ 364 if (clu.flags != p_dir->flags) { 365 /* no-fat-chain bit is disabled, 366 * so fat-chain should be synced with alloc-bitmap 367 */ 368 exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size); 369 p_dir->flags = ALLOC_FAT_CHAIN; 370 hint_femp.cur.flags = ALLOC_FAT_CHAIN; 371 } 372 373 if (clu.flags == ALLOC_FAT_CHAIN) 374 if (exfat_ent_set(sb, last_clu, clu.dir)) 375 return -EIO; 376 377 if (hint_femp.cur.dir == EXFAT_EOF_CLUSTER) 378 exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags); 379 380 hint_femp.count += sbi->dentries_per_clu; 381 382 hint_femp.cur.size++; 383 p_dir->size++; 384 size = EXFAT_CLU_TO_B(p_dir->size, sbi); 385 386 /* directory inode should be updated in here */ 387 i_size_write(inode, size); 388 ei->valid_size += sbi->cluster_size; 389 ei->flags = p_dir->flags; 390 inode->i_blocks += sbi->cluster_size >> 9; 391 } 392 393 p_dir->dir = exfat_sector_to_cluster(sbi, es->bh[0]->b_blocknr); 394 p_dir->size -= dentry / sbi->dentries_per_clu; 395 396 return dentry & (sbi->dentries_per_clu - 1); 397 } 398 399 /* 400 * Name Resolution Functions : 401 * Zero if it was successful; otherwise nonzero. 402 */ 403 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path, 404 struct exfat_uni_name *p_uniname, int lookup) 405 { 406 int namelen; 407 int lossy = NLS_NAME_NO_LOSSY; 408 struct super_block *sb = inode->i_sb; 409 int pathlen = strlen(path); 410 411 /* 412 * get the length of the pathname excluding 413 * trailing periods, if any. 414 */ 415 namelen = exfat_striptail_len(pathlen, path, false); 416 if (EXFAT_SB(sb)->options.keep_last_dots) { 417 /* 418 * Do not allow the creation of files with names 419 * ending with period(s). 420 */ 421 if (!lookup && (namelen < pathlen)) 422 return -EINVAL; 423 namelen = pathlen; 424 } 425 if (!namelen) 426 return -ENOENT; 427 if (pathlen > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE)) 428 return -ENAMETOOLONG; 429 430 /* 431 * strip all leading spaces : 432 * "MS windows 7" supports leading spaces. 433 * So we should skip this preprocessing for compatibility. 434 */ 435 436 /* file name conversion : 437 * If lookup case, we allow bad-name for compatibility. 438 */ 439 namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname, 440 &lossy); 441 if (namelen < 0) 442 return namelen; /* return error value */ 443 444 if ((lossy && !lookup) || !namelen) 445 return -EINVAL; 446 447 return 0; 448 } 449 450 static inline int exfat_resolve_path(struct inode *inode, 451 const unsigned char *path, struct exfat_uni_name *uni) 452 { 453 return __exfat_resolve_path(inode, path, uni, 0); 454 } 455 456 static inline int exfat_resolve_path_for_lookup(struct inode *inode, 457 const unsigned char *path, struct exfat_uni_name *uni) 458 { 459 return __exfat_resolve_path(inode, path, uni, 1); 460 } 461 462 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info) 463 { 464 return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff); 465 } 466 467 static int exfat_add_entry(struct inode *inode, const char *path, 468 unsigned int type, struct exfat_dir_entry *info) 469 { 470 int ret, dentry, num_entries; 471 struct super_block *sb = inode->i_sb; 472 struct exfat_sb_info *sbi = EXFAT_SB(sb); 473 struct exfat_uni_name uniname; 474 struct exfat_chain clu; 475 struct timespec64 ts = current_time(inode); 476 struct exfat_entry_set_cache es; 477 int clu_size = 0; 478 unsigned int start_clu = EXFAT_FREE_CLUSTER; 479 480 ret = exfat_resolve_path(inode, path, &uniname); 481 if (ret) 482 goto out; 483 484 num_entries = exfat_calc_num_entries(&uniname); 485 if (num_entries < 0) { 486 ret = num_entries; 487 goto out; 488 } 489 490 /* exfat_find_empty_entry must be called before alloc_cluster() */ 491 dentry = exfat_find_empty_entry(inode, &info->dir, num_entries, &es); 492 if (dentry < 0) { 493 ret = dentry; /* -EIO or -ENOSPC */ 494 goto out; 495 } 496 497 if (type == TYPE_DIR && !sbi->options.zero_size_dir) { 498 ret = exfat_alloc_new_dir(inode, &clu); 499 if (ret) { 500 exfat_put_dentry_set(&es, false); 501 goto out; 502 } 503 start_clu = clu.dir; 504 clu_size = sbi->cluster_size; 505 } 506 507 /* update the directory entry */ 508 /* fill the dos name directory entry information of the created file. 509 * the first cluster is not determined yet. (0) 510 */ 511 exfat_init_dir_entry(&es, type, start_clu, clu_size, &ts); 512 exfat_init_ext_entry(&es, num_entries, &uniname); 513 514 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 515 if (ret) 516 goto out; 517 518 info->entry = dentry; 519 info->flags = ALLOC_NO_FAT_CHAIN; 520 info->type = type; 521 522 if (type == TYPE_FILE) { 523 info->attr = EXFAT_ATTR_ARCHIVE; 524 info->start_clu = EXFAT_EOF_CLUSTER; 525 info->size = 0; 526 info->num_subdirs = 0; 527 } else { 528 info->attr = EXFAT_ATTR_SUBDIR; 529 if (sbi->options.zero_size_dir) 530 info->start_clu = EXFAT_EOF_CLUSTER; 531 else 532 info->start_clu = start_clu; 533 info->size = clu_size; 534 info->num_subdirs = EXFAT_MIN_SUBDIR; 535 } 536 info->valid_size = info->size; 537 538 memset(&info->crtime, 0, sizeof(info->crtime)); 539 memset(&info->mtime, 0, sizeof(info->mtime)); 540 memset(&info->atime, 0, sizeof(info->atime)); 541 out: 542 return ret; 543 } 544 545 static int exfat_create(struct mnt_idmap *idmap, struct inode *dir, 546 struct dentry *dentry, umode_t mode, bool excl) 547 { 548 struct super_block *sb = dir->i_sb; 549 struct inode *inode; 550 struct exfat_dir_entry info; 551 loff_t i_pos; 552 int err; 553 loff_t size = i_size_read(dir); 554 555 if (unlikely(exfat_forced_shutdown(sb))) 556 return -EIO; 557 558 mutex_lock(&EXFAT_SB(sb)->s_lock); 559 exfat_set_volume_dirty(sb); 560 err = exfat_add_entry(dir, dentry->d_name.name, TYPE_FILE, &info); 561 if (err) 562 goto unlock; 563 564 inode_inc_iversion(dir); 565 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 566 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 567 exfat_sync_inode(dir); 568 else 569 mark_inode_dirty(dir); 570 571 i_pos = exfat_make_i_pos(&info); 572 inode = exfat_build_inode(sb, &info, i_pos); 573 err = PTR_ERR_OR_ZERO(inode); 574 if (err) 575 goto unlock; 576 577 inode_inc_iversion(inode); 578 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 579 exfat_truncate_inode_atime(inode); 580 581 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 582 583 d_instantiate(dentry, inode); 584 unlock: 585 mutex_unlock(&EXFAT_SB(sb)->s_lock); 586 return err; 587 } 588 589 /* lookup a file */ 590 static int exfat_find(struct inode *dir, const struct qstr *qname, 591 struct exfat_dir_entry *info) 592 { 593 int ret, dentry, count; 594 struct exfat_chain cdir; 595 struct exfat_uni_name uni_name; 596 struct super_block *sb = dir->i_sb; 597 struct exfat_sb_info *sbi = EXFAT_SB(sb); 598 struct exfat_inode_info *ei = EXFAT_I(dir); 599 struct exfat_dentry *ep, *ep2; 600 struct exfat_entry_set_cache es; 601 /* for optimized dir & entry to prevent long traverse of cluster chain */ 602 struct exfat_hint hint_opt; 603 604 if (qname->len == 0) 605 return -ENOENT; 606 607 /* check the validity of directory name in the given pathname */ 608 ret = exfat_resolve_path_for_lookup(dir, qname->name, &uni_name); 609 if (ret) 610 return ret; 611 612 exfat_chain_set(&cdir, ei->start_clu, 613 EXFAT_B_TO_CLU(i_size_read(dir), sbi), ei->flags); 614 615 /* check the validation of hint_stat and initialize it if required */ 616 if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) { 617 ei->hint_stat.clu = cdir.dir; 618 ei->hint_stat.eidx = 0; 619 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff); 620 ei->hint_femp.eidx = EXFAT_HINT_NONE; 621 } 622 623 /* search the file name for directories */ 624 dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name, &hint_opt); 625 if (dentry < 0) 626 return dentry; /* -error value */ 627 628 /* adjust cdir to the optimized value */ 629 cdir.dir = hint_opt.clu; 630 if (cdir.flags & ALLOC_NO_FAT_CHAIN) 631 cdir.size -= dentry / sbi->dentries_per_clu; 632 dentry = hint_opt.eidx; 633 634 info->dir = cdir; 635 info->entry = dentry; 636 info->num_subdirs = 0; 637 638 if (exfat_get_dentry_set(&es, sb, &cdir, dentry, ES_2_ENTRIES)) 639 return -EIO; 640 ep = exfat_get_dentry_cached(&es, ES_IDX_FILE); 641 ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM); 642 643 info->type = exfat_get_entry_type(ep); 644 info->attr = le16_to_cpu(ep->dentry.file.attr); 645 info->valid_size = le64_to_cpu(ep2->dentry.stream.valid_size); 646 info->size = le64_to_cpu(ep2->dentry.stream.size); 647 648 if (info->valid_size < 0) { 649 exfat_fs_error(sb, "data valid size is invalid(%lld)", info->valid_size); 650 return -EIO; 651 } 652 653 if (unlikely(EXFAT_B_TO_CLU_ROUND_UP(info->size, sbi) > sbi->used_clusters)) { 654 exfat_fs_error(sb, "data size is invalid(%lld)", info->size); 655 return -EIO; 656 } 657 658 info->start_clu = le32_to_cpu(ep2->dentry.stream.start_clu); 659 if (!is_valid_cluster(sbi, info->start_clu) && info->size) { 660 exfat_warn(sb, "start_clu is invalid cluster(0x%x)", 661 info->start_clu); 662 info->size = 0; 663 info->valid_size = 0; 664 } 665 666 if (info->valid_size > info->size) { 667 exfat_warn(sb, "valid_size(%lld) is greater than size(%lld)", 668 info->valid_size, info->size); 669 info->valid_size = info->size; 670 } 671 672 if (info->size == 0) { 673 info->flags = ALLOC_NO_FAT_CHAIN; 674 info->start_clu = EXFAT_EOF_CLUSTER; 675 } else 676 info->flags = ep2->dentry.stream.flags; 677 678 exfat_get_entry_time(sbi, &info->crtime, 679 ep->dentry.file.create_tz, 680 ep->dentry.file.create_time, 681 ep->dentry.file.create_date, 682 ep->dentry.file.create_time_cs); 683 exfat_get_entry_time(sbi, &info->mtime, 684 ep->dentry.file.modify_tz, 685 ep->dentry.file.modify_time, 686 ep->dentry.file.modify_date, 687 ep->dentry.file.modify_time_cs); 688 exfat_get_entry_time(sbi, &info->atime, 689 ep->dentry.file.access_tz, 690 ep->dentry.file.access_time, 691 ep->dentry.file.access_date, 692 0); 693 exfat_put_dentry_set(&es, false); 694 695 if (ei->start_clu == EXFAT_FREE_CLUSTER) { 696 exfat_fs_error(sb, 697 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)", 698 i_size_read(dir), ei->dir.dir, ei->entry); 699 return -EIO; 700 } 701 702 if (info->type == TYPE_DIR) { 703 exfat_chain_set(&cdir, info->start_clu, 704 EXFAT_B_TO_CLU(info->size, sbi), info->flags); 705 count = exfat_count_dir_entries(sb, &cdir); 706 if (count < 0) 707 return -EIO; 708 709 info->num_subdirs = count + EXFAT_MIN_SUBDIR; 710 } 711 return 0; 712 } 713 714 static int exfat_d_anon_disconn(struct dentry *dentry) 715 { 716 return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED); 717 } 718 719 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry, 720 unsigned int flags) 721 { 722 struct super_block *sb = dir->i_sb; 723 struct inode *inode; 724 struct dentry *alias; 725 struct exfat_dir_entry info; 726 int err; 727 loff_t i_pos; 728 mode_t i_mode; 729 730 mutex_lock(&EXFAT_SB(sb)->s_lock); 731 err = exfat_find(dir, &dentry->d_name, &info); 732 if (err) { 733 if (err == -ENOENT) { 734 inode = NULL; 735 goto out; 736 } 737 goto unlock; 738 } 739 740 i_pos = exfat_make_i_pos(&info); 741 inode = exfat_build_inode(sb, &info, i_pos); 742 err = PTR_ERR_OR_ZERO(inode); 743 if (err) 744 goto unlock; 745 746 i_mode = inode->i_mode; 747 alias = d_find_alias(inode); 748 749 /* 750 * Checking "alias->d_parent == dentry->d_parent" to make sure 751 * FS is not corrupted (especially double linked dir). 752 */ 753 if (alias && alias->d_parent == dentry->d_parent && 754 !exfat_d_anon_disconn(alias)) { 755 756 /* 757 * Unhashed alias is able to exist because of revalidate() 758 * called by lookup_fast. You can easily make this status 759 * by calling create and lookup concurrently 760 * In such case, we reuse an alias instead of new dentry 761 */ 762 if (d_unhashed(alias)) { 763 WARN_ON(alias->d_name.hash_len != 764 dentry->d_name.hash_len); 765 exfat_info(sb, "rehashed a dentry(%p) in read lookup", 766 alias); 767 d_drop(dentry); 768 d_rehash(alias); 769 } else if (!S_ISDIR(i_mode)) { 770 /* 771 * This inode has non anonymous-DCACHE_DISCONNECTED 772 * dentry. This means, the user did ->lookup() by an 773 * another name (longname vs 8.3 alias of it) in past. 774 * 775 * Switch to new one for reason of locality if possible. 776 */ 777 d_move(alias, dentry); 778 } 779 iput(inode); 780 mutex_unlock(&EXFAT_SB(sb)->s_lock); 781 return alias; 782 } 783 dput(alias); 784 out: 785 mutex_unlock(&EXFAT_SB(sb)->s_lock); 786 if (!inode) 787 exfat_d_version_set(dentry, inode_query_iversion(dir)); 788 789 return d_splice_alias(inode, dentry); 790 unlock: 791 mutex_unlock(&EXFAT_SB(sb)->s_lock); 792 return ERR_PTR(err); 793 } 794 795 /* remove an entry, BUT don't truncate */ 796 static int exfat_unlink(struct inode *dir, struct dentry *dentry) 797 { 798 struct super_block *sb = dir->i_sb; 799 struct inode *inode = dentry->d_inode; 800 struct exfat_inode_info *ei = EXFAT_I(inode); 801 struct exfat_entry_set_cache es; 802 int err = 0; 803 804 if (unlikely(exfat_forced_shutdown(sb))) 805 return -EIO; 806 807 mutex_lock(&EXFAT_SB(sb)->s_lock); 808 if (ei->dir.dir == DIR_DELETED) { 809 exfat_err(sb, "abnormal access to deleted dentry"); 810 err = -ENOENT; 811 goto unlock; 812 } 813 814 err = exfat_get_dentry_set_by_ei(&es, sb, ei); 815 if (err) { 816 err = -EIO; 817 goto unlock; 818 } 819 820 exfat_set_volume_dirty(sb); 821 822 /* update the directory entry */ 823 exfat_remove_entries(inode, &es, ES_IDX_FILE); 824 825 err = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 826 if (err) 827 goto unlock; 828 829 /* This doesn't modify ei */ 830 ei->dir.dir = DIR_DELETED; 831 832 inode_inc_iversion(dir); 833 simple_inode_init_ts(dir); 834 exfat_truncate_inode_atime(dir); 835 mark_inode_dirty(dir); 836 837 clear_nlink(inode); 838 simple_inode_init_ts(inode); 839 exfat_truncate_inode_atime(inode); 840 exfat_unhash_inode(inode); 841 exfat_d_version_set(dentry, inode_query_iversion(dir)); 842 unlock: 843 mutex_unlock(&EXFAT_SB(sb)->s_lock); 844 return err; 845 } 846 847 static struct dentry *exfat_mkdir(struct mnt_idmap *idmap, struct inode *dir, 848 struct dentry *dentry, umode_t mode) 849 { 850 struct super_block *sb = dir->i_sb; 851 struct inode *inode; 852 struct exfat_dir_entry info; 853 loff_t i_pos; 854 int err; 855 loff_t size = i_size_read(dir); 856 857 if (unlikely(exfat_forced_shutdown(sb))) 858 return ERR_PTR(-EIO); 859 860 mutex_lock(&EXFAT_SB(sb)->s_lock); 861 exfat_set_volume_dirty(sb); 862 err = exfat_add_entry(dir, dentry->d_name.name, TYPE_DIR, &info); 863 if (err) 864 goto unlock; 865 866 inode_inc_iversion(dir); 867 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 868 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 869 exfat_sync_inode(dir); 870 else 871 mark_inode_dirty(dir); 872 inc_nlink(dir); 873 874 i_pos = exfat_make_i_pos(&info); 875 inode = exfat_build_inode(sb, &info, i_pos); 876 err = PTR_ERR_OR_ZERO(inode); 877 if (err) 878 goto unlock; 879 880 inode_inc_iversion(inode); 881 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 882 exfat_truncate_inode_atime(inode); 883 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 884 885 d_instantiate(dentry, inode); 886 887 unlock: 888 mutex_unlock(&EXFAT_SB(sb)->s_lock); 889 return ERR_PTR(err); 890 } 891 892 static int exfat_check_dir_empty(struct super_block *sb, 893 struct exfat_chain *p_dir) 894 { 895 int i, dentries_per_clu; 896 unsigned int type; 897 unsigned int clu_count = 0; 898 struct exfat_chain clu; 899 struct exfat_dentry *ep; 900 struct exfat_sb_info *sbi = EXFAT_SB(sb); 901 struct buffer_head *bh; 902 903 dentries_per_clu = sbi->dentries_per_clu; 904 905 if (p_dir->dir == EXFAT_EOF_CLUSTER) 906 return 0; 907 908 exfat_chain_dup(&clu, p_dir); 909 910 while (clu.dir != EXFAT_EOF_CLUSTER) { 911 for (i = 0; i < dentries_per_clu; i++) { 912 ep = exfat_get_dentry(sb, &clu, i, &bh); 913 if (!ep) 914 return -EIO; 915 type = exfat_get_entry_type(ep); 916 brelse(bh); 917 if (type == TYPE_UNUSED) 918 return 0; 919 920 if (type != TYPE_FILE && type != TYPE_DIR) 921 continue; 922 923 return -ENOTEMPTY; 924 } 925 926 if (clu.flags == ALLOC_NO_FAT_CHAIN) { 927 if (--clu.size > 0) 928 clu.dir++; 929 else 930 clu.dir = EXFAT_EOF_CLUSTER; 931 } else { 932 if (exfat_get_next_cluster(sb, &(clu.dir))) 933 return -EIO; 934 935 /* break if the cluster chain includes a loop */ 936 if (unlikely(++clu_count > EXFAT_DATA_CLUSTER_COUNT(sbi))) 937 break; 938 } 939 } 940 941 return 0; 942 } 943 944 static int exfat_rmdir(struct inode *dir, struct dentry *dentry) 945 { 946 struct inode *inode = dentry->d_inode; 947 struct exfat_chain clu_to_free; 948 struct super_block *sb = inode->i_sb; 949 struct exfat_sb_info *sbi = EXFAT_SB(sb); 950 struct exfat_inode_info *ei = EXFAT_I(inode); 951 struct exfat_entry_set_cache es; 952 int err; 953 954 if (unlikely(exfat_forced_shutdown(sb))) 955 return -EIO; 956 957 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock); 958 959 if (ei->dir.dir == DIR_DELETED) { 960 exfat_err(sb, "abnormal access to deleted dentry"); 961 err = -ENOENT; 962 goto unlock; 963 } 964 965 exfat_chain_set(&clu_to_free, ei->start_clu, 966 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags); 967 968 err = exfat_check_dir_empty(sb, &clu_to_free); 969 if (err) { 970 if (err == -EIO) 971 exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)", 972 err); 973 goto unlock; 974 } 975 976 err = exfat_get_dentry_set_by_ei(&es, sb, ei); 977 if (err) { 978 err = -EIO; 979 goto unlock; 980 } 981 982 exfat_set_volume_dirty(sb); 983 984 exfat_remove_entries(inode, &es, ES_IDX_FILE); 985 986 err = exfat_put_dentry_set(&es, IS_DIRSYNC(dir)); 987 if (err) 988 goto unlock; 989 990 ei->dir.dir = DIR_DELETED; 991 992 inode_inc_iversion(dir); 993 simple_inode_init_ts(dir); 994 exfat_truncate_inode_atime(dir); 995 if (IS_DIRSYNC(dir)) 996 exfat_sync_inode(dir); 997 else 998 mark_inode_dirty(dir); 999 drop_nlink(dir); 1000 1001 clear_nlink(inode); 1002 simple_inode_init_ts(inode); 1003 exfat_truncate_inode_atime(inode); 1004 exfat_unhash_inode(inode); 1005 exfat_d_version_set(dentry, inode_query_iversion(dir)); 1006 unlock: 1007 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock); 1008 return err; 1009 } 1010 1011 static int exfat_rename_file(struct inode *parent_inode, 1012 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei) 1013 { 1014 int ret, num_new_entries; 1015 struct exfat_dentry *epold, *epnew; 1016 struct super_block *sb = parent_inode->i_sb; 1017 struct exfat_entry_set_cache old_es, new_es; 1018 int sync = IS_DIRSYNC(parent_inode); 1019 1020 if (unlikely(exfat_forced_shutdown(sb))) 1021 return -EIO; 1022 1023 num_new_entries = exfat_calc_num_entries(p_uniname); 1024 if (num_new_entries < 0) 1025 return num_new_entries; 1026 1027 ret = exfat_get_dentry_set_by_ei(&old_es, sb, ei); 1028 if (ret) { 1029 ret = -EIO; 1030 return ret; 1031 } 1032 1033 epold = exfat_get_dentry_cached(&old_es, ES_IDX_FILE); 1034 1035 if (old_es.num_entries < num_new_entries) { 1036 int newentry; 1037 struct exfat_chain dir; 1038 1039 newentry = exfat_find_empty_entry(parent_inode, &dir, 1040 num_new_entries, &new_es); 1041 if (newentry < 0) { 1042 ret = newentry; /* -EIO or -ENOSPC */ 1043 goto put_old_es; 1044 } 1045 1046 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1047 *epnew = *epold; 1048 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1049 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1050 ei->attr |= EXFAT_ATTR_ARCHIVE; 1051 } 1052 1053 epold = exfat_get_dentry_cached(&old_es, ES_IDX_STREAM); 1054 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1055 *epnew = *epold; 1056 1057 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1058 1059 ret = exfat_put_dentry_set(&new_es, sync); 1060 if (ret) 1061 goto put_old_es; 1062 1063 exfat_remove_entries(parent_inode, &old_es, ES_IDX_FILE); 1064 ei->dir = dir; 1065 ei->entry = newentry; 1066 } else { 1067 if (exfat_get_entry_type(epold) == TYPE_FILE) { 1068 epold->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1069 ei->attr |= EXFAT_ATTR_ARCHIVE; 1070 } 1071 1072 exfat_remove_entries(parent_inode, &old_es, ES_IDX_FIRST_FILENAME + 1); 1073 exfat_init_ext_entry(&old_es, num_new_entries, p_uniname); 1074 } 1075 return exfat_put_dentry_set(&old_es, sync); 1076 1077 put_old_es: 1078 exfat_put_dentry_set(&old_es, false); 1079 return ret; 1080 } 1081 1082 static int exfat_move_file(struct inode *parent_inode, 1083 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei) 1084 { 1085 int ret, newentry, num_new_entries; 1086 struct exfat_dentry *epmov, *epnew; 1087 struct exfat_entry_set_cache mov_es, new_es; 1088 struct exfat_chain newdir; 1089 1090 num_new_entries = exfat_calc_num_entries(p_uniname); 1091 if (num_new_entries < 0) 1092 return num_new_entries; 1093 1094 ret = exfat_get_dentry_set_by_ei(&mov_es, parent_inode->i_sb, ei); 1095 if (ret) 1096 return -EIO; 1097 1098 newentry = exfat_find_empty_entry(parent_inode, &newdir, 1099 num_new_entries, &new_es); 1100 if (newentry < 0) { 1101 ret = newentry; /* -EIO or -ENOSPC */ 1102 goto put_mov_es; 1103 } 1104 1105 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_FILE); 1106 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1107 *epnew = *epmov; 1108 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1109 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1110 ei->attr |= EXFAT_ATTR_ARCHIVE; 1111 } 1112 1113 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_STREAM); 1114 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1115 *epnew = *epmov; 1116 1117 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1118 exfat_remove_entries(parent_inode, &mov_es, ES_IDX_FILE); 1119 1120 ei->dir = newdir; 1121 ei->entry = newentry; 1122 1123 ret = exfat_put_dentry_set(&new_es, IS_DIRSYNC(parent_inode)); 1124 if (ret) 1125 goto put_mov_es; 1126 1127 return exfat_put_dentry_set(&mov_es, IS_DIRSYNC(parent_inode)); 1128 1129 put_mov_es: 1130 exfat_put_dentry_set(&mov_es, false); 1131 1132 return ret; 1133 } 1134 1135 /* rename or move a old file into a new file */ 1136 static int __exfat_rename(struct inode *old_parent_inode, 1137 struct exfat_inode_info *ei, struct inode *new_parent_inode, 1138 struct dentry *new_dentry) 1139 { 1140 int ret; 1141 struct exfat_uni_name uni_name; 1142 struct super_block *sb = old_parent_inode->i_sb; 1143 struct exfat_sb_info *sbi = EXFAT_SB(sb); 1144 const unsigned char *new_path = new_dentry->d_name.name; 1145 struct inode *new_inode = new_dentry->d_inode; 1146 struct exfat_inode_info *new_ei = NULL; 1147 1148 /* check the validity of pointer parameters */ 1149 if (new_path == NULL || strlen(new_path) == 0) 1150 return -EINVAL; 1151 1152 if (ei->dir.dir == DIR_DELETED) { 1153 exfat_err(sb, "abnormal access to deleted source dentry"); 1154 return -ENOENT; 1155 } 1156 1157 /* check whether new dir is existing directory and empty */ 1158 if (new_inode) { 1159 ret = -EIO; 1160 new_ei = EXFAT_I(new_inode); 1161 1162 if (new_ei->dir.dir == DIR_DELETED) { 1163 exfat_err(sb, "abnormal access to deleted target dentry"); 1164 goto out; 1165 } 1166 1167 /* if new_inode exists, update ei */ 1168 if (S_ISDIR(new_inode->i_mode)) { 1169 struct exfat_chain new_clu; 1170 1171 new_clu.dir = new_ei->start_clu; 1172 new_clu.size = 1173 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1174 sbi); 1175 new_clu.flags = new_ei->flags; 1176 1177 ret = exfat_check_dir_empty(sb, &new_clu); 1178 if (ret) 1179 goto out; 1180 } 1181 } 1182 1183 /* check the validity of directory name in the given new pathname */ 1184 ret = exfat_resolve_path(new_parent_inode, new_path, &uni_name); 1185 if (ret) 1186 goto out; 1187 1188 exfat_set_volume_dirty(sb); 1189 1190 if (new_parent_inode == old_parent_inode) 1191 ret = exfat_rename_file(new_parent_inode, &uni_name, ei); 1192 else 1193 ret = exfat_move_file(new_parent_inode, &uni_name, ei); 1194 1195 if (!ret && new_inode) { 1196 struct exfat_entry_set_cache es; 1197 1198 /* delete entries of new_dir */ 1199 ret = exfat_get_dentry_set_by_ei(&es, sb, new_ei); 1200 if (ret) { 1201 ret = -EIO; 1202 goto del_out; 1203 } 1204 1205 exfat_remove_entries(new_inode, &es, ES_IDX_FILE); 1206 1207 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(new_inode)); 1208 if (ret) 1209 goto del_out; 1210 1211 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */ 1212 if (S_ISDIR(new_inode->i_mode) && 1213 new_ei->start_clu != EXFAT_EOF_CLUSTER) { 1214 /* new_ei, new_clu_to_free */ 1215 struct exfat_chain new_clu_to_free; 1216 1217 exfat_chain_set(&new_clu_to_free, new_ei->start_clu, 1218 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1219 sbi), new_ei->flags); 1220 1221 if (exfat_free_cluster(new_inode, &new_clu_to_free)) { 1222 /* just set I/O error only */ 1223 ret = -EIO; 1224 } 1225 1226 i_size_write(new_inode, 0); 1227 new_ei->valid_size = 0; 1228 new_ei->start_clu = EXFAT_EOF_CLUSTER; 1229 new_ei->flags = ALLOC_NO_FAT_CHAIN; 1230 } 1231 del_out: 1232 /* Update new_inode ei 1233 * Prevent syncing removed new_inode 1234 * (new_ei is already initialized above code ("if (new_inode)") 1235 */ 1236 new_ei->dir.dir = DIR_DELETED; 1237 } 1238 out: 1239 return ret; 1240 } 1241 1242 static int exfat_rename(struct mnt_idmap *idmap, 1243 struct inode *old_dir, struct dentry *old_dentry, 1244 struct inode *new_dir, struct dentry *new_dentry, 1245 unsigned int flags) 1246 { 1247 struct inode *old_inode, *new_inode; 1248 struct super_block *sb = old_dir->i_sb; 1249 loff_t i_pos; 1250 int err; 1251 loff_t size = i_size_read(new_dir); 1252 1253 /* 1254 * The VFS already checks for existence, so for local filesystems 1255 * the RENAME_NOREPLACE implementation is equivalent to plain rename. 1256 * Don't support any other flags 1257 */ 1258 if (flags & ~RENAME_NOREPLACE) 1259 return -EINVAL; 1260 1261 mutex_lock(&EXFAT_SB(sb)->s_lock); 1262 old_inode = old_dentry->d_inode; 1263 new_inode = new_dentry->d_inode; 1264 1265 err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry); 1266 if (err) 1267 goto unlock; 1268 1269 inode_inc_iversion(new_dir); 1270 simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry); 1271 EXFAT_I(new_dir)->i_crtime = current_time(new_dir); 1272 exfat_truncate_inode_atime(new_dir); 1273 if (IS_DIRSYNC(new_dir) && size != i_size_read(new_dir)) 1274 exfat_sync_inode(new_dir); 1275 else 1276 mark_inode_dirty(new_dir); 1277 1278 i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) | 1279 (EXFAT_I(old_inode)->entry & 0xffffffff); 1280 exfat_unhash_inode(old_inode); 1281 exfat_hash_inode(old_inode, i_pos); 1282 if (IS_DIRSYNC(new_dir)) 1283 exfat_sync_inode(old_inode); 1284 else 1285 mark_inode_dirty(old_inode); 1286 1287 if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) { 1288 drop_nlink(old_dir); 1289 if (!new_inode) 1290 inc_nlink(new_dir); 1291 } 1292 1293 inode_inc_iversion(old_dir); 1294 if (new_dir != old_dir) 1295 mark_inode_dirty(old_dir); 1296 1297 if (new_inode) { 1298 exfat_unhash_inode(new_inode); 1299 1300 /* skip drop_nlink if new_inode already has been dropped */ 1301 if (new_inode->i_nlink) { 1302 drop_nlink(new_inode); 1303 if (S_ISDIR(new_inode->i_mode)) 1304 drop_nlink(new_inode); 1305 } else { 1306 exfat_warn(sb, "abnormal access to an inode dropped"); 1307 WARN_ON(new_inode->i_nlink == 0); 1308 } 1309 EXFAT_I(new_inode)->i_crtime = current_time(new_inode); 1310 } 1311 1312 unlock: 1313 mutex_unlock(&EXFAT_SB(sb)->s_lock); 1314 return err; 1315 } 1316 1317 const struct inode_operations exfat_dir_inode_operations = { 1318 .create = exfat_create, 1319 .lookup = exfat_lookup, 1320 .unlink = exfat_unlink, 1321 .mkdir = exfat_mkdir, 1322 .rmdir = exfat_rmdir, 1323 .rename = exfat_rename, 1324 .setattr = exfat_setattr, 1325 .getattr = exfat_getattr, 1326 }; 1327