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 15static inline unsigned long exfat_d_version(struct dentry *dentry) 16{ 17 return (unsigned long) dentry->d_fsdata; 18} 19 20static 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 */ 34static 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 */ 69static 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 */ 84static 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 106static 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 135const 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 141static 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 167static 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 201const 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 */ 208static 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 279static 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 */ 294static 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_ondisk += sbi->cluster_size; 376 ei->i_size_aligned += sbi->cluster_size; 377 ei->valid_size += sbi->cluster_size; 378 ei->flags = p_dir->flags; 379 inode->i_blocks += sbi->cluster_size >> 9; 380 } 381 382 return dentry; 383} 384 385/* 386 * Name Resolution Functions : 387 * Zero if it was successful; otherwise nonzero. 388 */ 389static int __exfat_resolve_path(struct inode *inode, const unsigned char *path, 390 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname, 391 int lookup) 392{ 393 int namelen; 394 int lossy = NLS_NAME_NO_LOSSY; 395 struct super_block *sb = inode->i_sb; 396 struct exfat_sb_info *sbi = EXFAT_SB(sb); 397 struct exfat_inode_info *ei = EXFAT_I(inode); 398 int pathlen = strlen(path); 399 400 /* 401 * get the length of the pathname excluding 402 * trailing periods, if any. 403 */ 404 namelen = exfat_striptail_len(pathlen, path, false); 405 if (EXFAT_SB(sb)->options.keep_last_dots) { 406 /* 407 * Do not allow the creation of files with names 408 * ending with period(s). 409 */ 410 if (!lookup && (namelen < pathlen)) 411 return -EINVAL; 412 namelen = pathlen; 413 } 414 if (!namelen) 415 return -ENOENT; 416 if (pathlen > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE)) 417 return -ENAMETOOLONG; 418 419 /* 420 * strip all leading spaces : 421 * "MS windows 7" supports leading spaces. 422 * So we should skip this preprocessing for compatibility. 423 */ 424 425 /* file name conversion : 426 * If lookup case, we allow bad-name for compatibility. 427 */ 428 namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname, 429 &lossy); 430 if (namelen < 0) 431 return namelen; /* return error value */ 432 433 if ((lossy && !lookup) || !namelen) 434 return (lossy & NLS_NAME_OVERLEN) ? -ENAMETOOLONG : -EINVAL; 435 436 exfat_chain_set(p_dir, ei->start_clu, 437 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags); 438 439 return 0; 440} 441 442static inline int exfat_resolve_path(struct inode *inode, 443 const unsigned char *path, struct exfat_chain *dir, 444 struct exfat_uni_name *uni) 445{ 446 return __exfat_resolve_path(inode, path, dir, uni, 0); 447} 448 449static inline int exfat_resolve_path_for_lookup(struct inode *inode, 450 const unsigned char *path, struct exfat_chain *dir, 451 struct exfat_uni_name *uni) 452{ 453 return __exfat_resolve_path(inode, path, dir, uni, 1); 454} 455 456static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info) 457{ 458 return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff); 459} 460 461static int exfat_add_entry(struct inode *inode, const char *path, 462 struct exfat_chain *p_dir, unsigned int type, 463 struct exfat_dir_entry *info) 464{ 465 int ret, dentry, num_entries; 466 struct super_block *sb = inode->i_sb; 467 struct exfat_sb_info *sbi = EXFAT_SB(sb); 468 struct exfat_uni_name uniname; 469 struct exfat_chain clu; 470 struct timespec64 ts = current_time(inode); 471 struct exfat_entry_set_cache es; 472 int clu_size = 0; 473 unsigned int start_clu = EXFAT_FREE_CLUSTER; 474 475 ret = exfat_resolve_path(inode, path, p_dir, &uniname); 476 if (ret) 477 goto out; 478 479 num_entries = exfat_calc_num_entries(&uniname); 480 if (num_entries < 0) { 481 ret = num_entries; 482 goto out; 483 } 484 485 /* exfat_find_empty_entry must be called before alloc_cluster() */ 486 dentry = exfat_find_empty_entry(inode, p_dir, num_entries, &es); 487 if (dentry < 0) { 488 ret = dentry; /* -EIO or -ENOSPC */ 489 goto out; 490 } 491 492 if (type == TYPE_DIR && !sbi->options.zero_size_dir) { 493 ret = exfat_alloc_new_dir(inode, &clu); 494 if (ret) { 495 exfat_put_dentry_set(&es, false); 496 goto out; 497 } 498 start_clu = clu.dir; 499 clu_size = sbi->cluster_size; 500 } 501 502 /* update the directory entry */ 503 /* fill the dos name directory entry information of the created file. 504 * the first cluster is not determined yet. (0) 505 */ 506 exfat_init_dir_entry(&es, type, start_clu, clu_size, &ts); 507 exfat_init_ext_entry(&es, num_entries, &uniname); 508 509 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 510 if (ret) 511 goto out; 512 513 info->dir = *p_dir; 514 info->entry = dentry; 515 info->flags = ALLOC_NO_FAT_CHAIN; 516 info->type = type; 517 518 if (type == TYPE_FILE) { 519 info->attr = EXFAT_ATTR_ARCHIVE; 520 info->start_clu = EXFAT_EOF_CLUSTER; 521 info->size = 0; 522 info->num_subdirs = 0; 523 } else { 524 info->attr = EXFAT_ATTR_SUBDIR; 525 if (sbi->options.zero_size_dir) 526 info->start_clu = EXFAT_EOF_CLUSTER; 527 else 528 info->start_clu = start_clu; 529 info->size = clu_size; 530 info->num_subdirs = EXFAT_MIN_SUBDIR; 531 } 532 info->valid_size = info->size; 533 534 memset(&info->crtime, 0, sizeof(info->crtime)); 535 memset(&info->mtime, 0, sizeof(info->mtime)); 536 memset(&info->atime, 0, sizeof(info->atime)); 537out: 538 return ret; 539} 540 541static int exfat_create(struct mnt_idmap *idmap, struct inode *dir, 542 struct dentry *dentry, umode_t mode, bool excl) 543{ 544 struct super_block *sb = dir->i_sb; 545 struct inode *inode; 546 struct exfat_chain cdir; 547 struct exfat_dir_entry info; 548 loff_t i_pos; 549 int err; 550 loff_t size = i_size_read(dir); 551 552 mutex_lock(&EXFAT_SB(sb)->s_lock); 553 exfat_set_volume_dirty(sb); 554 err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE, 555 &info); 556 if (err) 557 goto unlock; 558 559 inode_inc_iversion(dir); 560 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 561 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 562 exfat_sync_inode(dir); 563 else 564 mark_inode_dirty(dir); 565 566 i_pos = exfat_make_i_pos(&info); 567 inode = exfat_build_inode(sb, &info, i_pos); 568 err = PTR_ERR_OR_ZERO(inode); 569 if (err) 570 goto unlock; 571 572 inode_inc_iversion(inode); 573 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 574 exfat_truncate_inode_atime(inode); 575 576 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 577 578 d_instantiate(dentry, inode); 579unlock: 580 mutex_unlock(&EXFAT_SB(sb)->s_lock); 581 return err; 582} 583 584/* lookup a file */ 585static int exfat_find(struct inode *dir, struct qstr *qname, 586 struct exfat_dir_entry *info) 587{ 588 int ret, dentry, count; 589 struct exfat_chain cdir; 590 struct exfat_uni_name uni_name; 591 struct super_block *sb = dir->i_sb; 592 struct exfat_sb_info *sbi = EXFAT_SB(sb); 593 struct exfat_inode_info *ei = EXFAT_I(dir); 594 struct exfat_dentry *ep, *ep2; 595 struct exfat_entry_set_cache es; 596 /* for optimized dir & entry to prevent long traverse of cluster chain */ 597 struct exfat_hint hint_opt; 598 599 if (qname->len == 0) 600 return -ENOENT; 601 602 /* check the validity of directory name in the given pathname */ 603 ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name); 604 if (ret) 605 return ret; 606 607 /* check the validation of hint_stat and initialize it if required */ 608 if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) { 609 ei->hint_stat.clu = cdir.dir; 610 ei->hint_stat.eidx = 0; 611 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff); 612 ei->hint_femp.eidx = EXFAT_HINT_NONE; 613 } 614 615 /* search the file name for directories */ 616 dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name, &hint_opt); 617 if (dentry < 0) 618 return dentry; /* -error value */ 619 620 info->dir = cdir; 621 info->entry = dentry; 622 info->num_subdirs = 0; 623 624 /* adjust cdir to the optimized value */ 625 cdir.dir = hint_opt.clu; 626 if (cdir.flags & ALLOC_NO_FAT_CHAIN) 627 cdir.size -= dentry / sbi->dentries_per_clu; 628 dentry = hint_opt.eidx; 629 if (exfat_get_dentry_set(&es, sb, &cdir, dentry, ES_2_ENTRIES)) 630 return -EIO; 631 ep = exfat_get_dentry_cached(&es, ES_IDX_FILE); 632 ep2 = exfat_get_dentry_cached(&es, ES_IDX_STREAM); 633 634 info->type = exfat_get_entry_type(ep); 635 info->attr = le16_to_cpu(ep->dentry.file.attr); 636 info->size = le64_to_cpu(ep2->dentry.stream.valid_size); 637 info->valid_size = le64_to_cpu(ep2->dentry.stream.valid_size); 638 info->size = le64_to_cpu(ep2->dentry.stream.size); 639 if (info->size == 0) { 640 info->flags = ALLOC_NO_FAT_CHAIN; 641 info->start_clu = EXFAT_EOF_CLUSTER; 642 } else { 643 info->flags = ep2->dentry.stream.flags; 644 info->start_clu = 645 le32_to_cpu(ep2->dentry.stream.start_clu); 646 } 647 648 exfat_get_entry_time(sbi, &info->crtime, 649 ep->dentry.file.create_tz, 650 ep->dentry.file.create_time, 651 ep->dentry.file.create_date, 652 ep->dentry.file.create_time_cs); 653 exfat_get_entry_time(sbi, &info->mtime, 654 ep->dentry.file.modify_tz, 655 ep->dentry.file.modify_time, 656 ep->dentry.file.modify_date, 657 ep->dentry.file.modify_time_cs); 658 exfat_get_entry_time(sbi, &info->atime, 659 ep->dentry.file.access_tz, 660 ep->dentry.file.access_time, 661 ep->dentry.file.access_date, 662 0); 663 exfat_put_dentry_set(&es, false); 664 665 if (ei->start_clu == EXFAT_FREE_CLUSTER) { 666 exfat_fs_error(sb, 667 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)", 668 i_size_read(dir), ei->dir.dir, ei->entry); 669 return -EIO; 670 } 671 672 if (info->type == TYPE_DIR) { 673 exfat_chain_set(&cdir, info->start_clu, 674 EXFAT_B_TO_CLU(info->size, sbi), info->flags); 675 count = exfat_count_dir_entries(sb, &cdir); 676 if (count < 0) 677 return -EIO; 678 679 info->num_subdirs = count + EXFAT_MIN_SUBDIR; 680 } 681 return 0; 682} 683 684static int exfat_d_anon_disconn(struct dentry *dentry) 685{ 686 return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED); 687} 688 689static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry, 690 unsigned int flags) 691{ 692 struct super_block *sb = dir->i_sb; 693 struct inode *inode; 694 struct dentry *alias; 695 struct exfat_dir_entry info; 696 int err; 697 loff_t i_pos; 698 mode_t i_mode; 699 700 mutex_lock(&EXFAT_SB(sb)->s_lock); 701 err = exfat_find(dir, &dentry->d_name, &info); 702 if (err) { 703 if (err == -ENOENT) { 704 inode = NULL; 705 goto out; 706 } 707 goto unlock; 708 } 709 710 i_pos = exfat_make_i_pos(&info); 711 inode = exfat_build_inode(sb, &info, i_pos); 712 err = PTR_ERR_OR_ZERO(inode); 713 if (err) 714 goto unlock; 715 716 i_mode = inode->i_mode; 717 alias = d_find_alias(inode); 718 719 /* 720 * Checking "alias->d_parent == dentry->d_parent" to make sure 721 * FS is not corrupted (especially double linked dir). 722 */ 723 if (alias && alias->d_parent == dentry->d_parent && 724 !exfat_d_anon_disconn(alias)) { 725 726 /* 727 * Unhashed alias is able to exist because of revalidate() 728 * called by lookup_fast. You can easily make this status 729 * by calling create and lookup concurrently 730 * In such case, we reuse an alias instead of new dentry 731 */ 732 if (d_unhashed(alias)) { 733 WARN_ON(alias->d_name.hash_len != 734 dentry->d_name.hash_len); 735 exfat_info(sb, "rehashed a dentry(%p) in read lookup", 736 alias); 737 d_drop(dentry); 738 d_rehash(alias); 739 } else if (!S_ISDIR(i_mode)) { 740 /* 741 * This inode has non anonymous-DCACHE_DISCONNECTED 742 * dentry. This means, the user did ->lookup() by an 743 * another name (longname vs 8.3 alias of it) in past. 744 * 745 * Switch to new one for reason of locality if possible. 746 */ 747 d_move(alias, dentry); 748 } 749 iput(inode); 750 mutex_unlock(&EXFAT_SB(sb)->s_lock); 751 return alias; 752 } 753 dput(alias); 754out: 755 mutex_unlock(&EXFAT_SB(sb)->s_lock); 756 if (!inode) 757 exfat_d_version_set(dentry, inode_query_iversion(dir)); 758 759 return d_splice_alias(inode, dentry); 760unlock: 761 mutex_unlock(&EXFAT_SB(sb)->s_lock); 762 return ERR_PTR(err); 763} 764 765/* remove an entry, BUT don't truncate */ 766static int exfat_unlink(struct inode *dir, struct dentry *dentry) 767{ 768 struct exfat_chain cdir; 769 struct super_block *sb = dir->i_sb; 770 struct inode *inode = dentry->d_inode; 771 struct exfat_inode_info *ei = EXFAT_I(inode); 772 struct exfat_entry_set_cache es; 773 int entry, err = 0; 774 775 mutex_lock(&EXFAT_SB(sb)->s_lock); 776 exfat_chain_dup(&cdir, &ei->dir); 777 entry = ei->entry; 778 if (ei->dir.dir == DIR_DELETED) { 779 exfat_err(sb, "abnormal access to deleted dentry"); 780 err = -ENOENT; 781 goto unlock; 782 } 783 784 err = exfat_get_dentry_set(&es, sb, &cdir, entry, ES_ALL_ENTRIES); 785 if (err) { 786 err = -EIO; 787 goto unlock; 788 } 789 790 exfat_set_volume_dirty(sb); 791 792 /* update the directory entry */ 793 exfat_remove_entries(inode, &es, ES_IDX_FILE); 794 795 err = exfat_put_dentry_set(&es, IS_DIRSYNC(inode)); 796 if (err) 797 goto unlock; 798 799 /* This doesn't modify ei */ 800 ei->dir.dir = DIR_DELETED; 801 802 inode_inc_iversion(dir); 803 simple_inode_init_ts(dir); 804 exfat_truncate_inode_atime(dir); 805 mark_inode_dirty(dir); 806 807 clear_nlink(inode); 808 simple_inode_init_ts(inode); 809 exfat_truncate_inode_atime(inode); 810 exfat_unhash_inode(inode); 811 exfat_d_version_set(dentry, inode_query_iversion(dir)); 812unlock: 813 mutex_unlock(&EXFAT_SB(sb)->s_lock); 814 return err; 815} 816 817static int exfat_mkdir(struct mnt_idmap *idmap, struct inode *dir, 818 struct dentry *dentry, umode_t mode) 819{ 820 struct super_block *sb = dir->i_sb; 821 struct inode *inode; 822 struct exfat_dir_entry info; 823 struct exfat_chain cdir; 824 loff_t i_pos; 825 int err; 826 loff_t size = i_size_read(dir); 827 828 mutex_lock(&EXFAT_SB(sb)->s_lock); 829 exfat_set_volume_dirty(sb); 830 err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR, 831 &info); 832 if (err) 833 goto unlock; 834 835 inode_inc_iversion(dir); 836 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); 837 if (IS_DIRSYNC(dir) && size != i_size_read(dir)) 838 exfat_sync_inode(dir); 839 else 840 mark_inode_dirty(dir); 841 inc_nlink(dir); 842 843 i_pos = exfat_make_i_pos(&info); 844 inode = exfat_build_inode(sb, &info, i_pos); 845 err = PTR_ERR_OR_ZERO(inode); 846 if (err) 847 goto unlock; 848 849 inode_inc_iversion(inode); 850 EXFAT_I(inode)->i_crtime = simple_inode_init_ts(inode); 851 exfat_truncate_inode_atime(inode); 852 /* timestamp is already written, so mark_inode_dirty() is unneeded. */ 853 854 d_instantiate(dentry, inode); 855 856unlock: 857 mutex_unlock(&EXFAT_SB(sb)->s_lock); 858 return err; 859} 860 861static int exfat_check_dir_empty(struct super_block *sb, 862 struct exfat_chain *p_dir) 863{ 864 int i, dentries_per_clu; 865 unsigned int type; 866 struct exfat_chain clu; 867 struct exfat_dentry *ep; 868 struct exfat_sb_info *sbi = EXFAT_SB(sb); 869 struct buffer_head *bh; 870 871 dentries_per_clu = sbi->dentries_per_clu; 872 873 if (p_dir->dir == EXFAT_EOF_CLUSTER) 874 return 0; 875 876 exfat_chain_dup(&clu, p_dir); 877 878 while (clu.dir != EXFAT_EOF_CLUSTER) { 879 for (i = 0; i < dentries_per_clu; i++) { 880 ep = exfat_get_dentry(sb, &clu, i, &bh); 881 if (!ep) 882 return -EIO; 883 type = exfat_get_entry_type(ep); 884 brelse(bh); 885 if (type == TYPE_UNUSED) 886 return 0; 887 888 if (type != TYPE_FILE && type != TYPE_DIR) 889 continue; 890 891 return -ENOTEMPTY; 892 } 893 894 if (clu.flags == ALLOC_NO_FAT_CHAIN) { 895 if (--clu.size > 0) 896 clu.dir++; 897 else 898 clu.dir = EXFAT_EOF_CLUSTER; 899 } else { 900 if (exfat_get_next_cluster(sb, &(clu.dir))) 901 return -EIO; 902 } 903 } 904 905 return 0; 906} 907 908static int exfat_rmdir(struct inode *dir, struct dentry *dentry) 909{ 910 struct inode *inode = dentry->d_inode; 911 struct exfat_chain cdir, clu_to_free; 912 struct super_block *sb = inode->i_sb; 913 struct exfat_sb_info *sbi = EXFAT_SB(sb); 914 struct exfat_inode_info *ei = EXFAT_I(inode); 915 struct exfat_entry_set_cache es; 916 int entry, err; 917 918 mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock); 919 920 exfat_chain_dup(&cdir, &ei->dir); 921 entry = ei->entry; 922 923 if (ei->dir.dir == DIR_DELETED) { 924 exfat_err(sb, "abnormal access to deleted dentry"); 925 err = -ENOENT; 926 goto unlock; 927 } 928 929 exfat_chain_set(&clu_to_free, ei->start_clu, 930 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags); 931 932 err = exfat_check_dir_empty(sb, &clu_to_free); 933 if (err) { 934 if (err == -EIO) 935 exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)", 936 err); 937 goto unlock; 938 } 939 940 err = exfat_get_dentry_set(&es, sb, &cdir, entry, ES_ALL_ENTRIES); 941 if (err) { 942 err = -EIO; 943 goto unlock; 944 } 945 946 exfat_set_volume_dirty(sb); 947 948 exfat_remove_entries(inode, &es, ES_IDX_FILE); 949 950 err = exfat_put_dentry_set(&es, IS_DIRSYNC(dir)); 951 if (err) 952 goto unlock; 953 954 ei->dir.dir = DIR_DELETED; 955 956 inode_inc_iversion(dir); 957 simple_inode_init_ts(dir); 958 exfat_truncate_inode_atime(dir); 959 if (IS_DIRSYNC(dir)) 960 exfat_sync_inode(dir); 961 else 962 mark_inode_dirty(dir); 963 drop_nlink(dir); 964 965 clear_nlink(inode); 966 simple_inode_init_ts(inode); 967 exfat_truncate_inode_atime(inode); 968 exfat_unhash_inode(inode); 969 exfat_d_version_set(dentry, inode_query_iversion(dir)); 970unlock: 971 mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock); 972 return err; 973} 974 975static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir, 976 int oldentry, struct exfat_uni_name *p_uniname, 977 struct exfat_inode_info *ei) 978{ 979 int ret, num_new_entries; 980 struct exfat_dentry *epold, *epnew; 981 struct super_block *sb = inode->i_sb; 982 struct exfat_entry_set_cache old_es, new_es; 983 int sync = IS_DIRSYNC(inode); 984 985 num_new_entries = exfat_calc_num_entries(p_uniname); 986 if (num_new_entries < 0) 987 return num_new_entries; 988 989 ret = exfat_get_dentry_set(&old_es, sb, p_dir, oldentry, ES_ALL_ENTRIES); 990 if (ret) { 991 ret = -EIO; 992 return ret; 993 } 994 995 epold = exfat_get_dentry_cached(&old_es, ES_IDX_FILE); 996 997 if (old_es.num_entries < num_new_entries) { 998 int newentry; 999 1000 newentry = exfat_find_empty_entry(inode, p_dir, num_new_entries, 1001 &new_es); 1002 if (newentry < 0) { 1003 ret = newentry; /* -EIO or -ENOSPC */ 1004 goto put_old_es; 1005 } 1006 1007 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1008 *epnew = *epold; 1009 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1010 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1011 ei->attr |= EXFAT_ATTR_ARCHIVE; 1012 } 1013 1014 epold = exfat_get_dentry_cached(&old_es, ES_IDX_STREAM); 1015 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1016 *epnew = *epold; 1017 1018 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1019 1020 ret = exfat_put_dentry_set(&new_es, sync); 1021 if (ret) 1022 goto put_old_es; 1023 1024 exfat_remove_entries(inode, &old_es, ES_IDX_FILE); 1025 ei->dir = *p_dir; 1026 ei->entry = newentry; 1027 } else { 1028 if (exfat_get_entry_type(epold) == TYPE_FILE) { 1029 epold->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1030 ei->attr |= EXFAT_ATTR_ARCHIVE; 1031 } 1032 1033 exfat_remove_entries(inode, &old_es, ES_IDX_FIRST_FILENAME + 1); 1034 exfat_init_ext_entry(&old_es, num_new_entries, p_uniname); 1035 } 1036 return exfat_put_dentry_set(&old_es, sync); 1037 1038put_old_es: 1039 exfat_put_dentry_set(&old_es, false); 1040 return ret; 1041} 1042 1043static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir, 1044 int oldentry, struct exfat_chain *p_newdir, 1045 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei) 1046{ 1047 int ret, newentry, num_new_entries; 1048 struct exfat_dentry *epmov, *epnew; 1049 struct super_block *sb = inode->i_sb; 1050 struct exfat_entry_set_cache mov_es, new_es; 1051 1052 num_new_entries = exfat_calc_num_entries(p_uniname); 1053 if (num_new_entries < 0) 1054 return num_new_entries; 1055 1056 ret = exfat_get_dentry_set(&mov_es, sb, p_olddir, oldentry, 1057 ES_ALL_ENTRIES); 1058 if (ret) 1059 return -EIO; 1060 1061 newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries, 1062 &new_es); 1063 if (newentry < 0) { 1064 ret = newentry; /* -EIO or -ENOSPC */ 1065 goto put_mov_es; 1066 } 1067 1068 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_FILE); 1069 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_FILE); 1070 *epnew = *epmov; 1071 if (exfat_get_entry_type(epnew) == TYPE_FILE) { 1072 epnew->dentry.file.attr |= cpu_to_le16(EXFAT_ATTR_ARCHIVE); 1073 ei->attr |= EXFAT_ATTR_ARCHIVE; 1074 } 1075 1076 epmov = exfat_get_dentry_cached(&mov_es, ES_IDX_STREAM); 1077 epnew = exfat_get_dentry_cached(&new_es, ES_IDX_STREAM); 1078 *epnew = *epmov; 1079 1080 exfat_init_ext_entry(&new_es, num_new_entries, p_uniname); 1081 exfat_remove_entries(inode, &mov_es, ES_IDX_FILE); 1082 1083 exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size, 1084 p_newdir->flags); 1085 1086 ei->entry = newentry; 1087 1088 ret = exfat_put_dentry_set(&new_es, IS_DIRSYNC(inode)); 1089 if (ret) 1090 goto put_mov_es; 1091 1092 return exfat_put_dentry_set(&mov_es, IS_DIRSYNC(inode)); 1093 1094put_mov_es: 1095 exfat_put_dentry_set(&mov_es, false); 1096 1097 return ret; 1098} 1099 1100/* rename or move a old file into a new file */ 1101static int __exfat_rename(struct inode *old_parent_inode, 1102 struct exfat_inode_info *ei, struct inode *new_parent_inode, 1103 struct dentry *new_dentry) 1104{ 1105 int ret; 1106 int dentry; 1107 struct exfat_chain olddir, newdir; 1108 struct exfat_chain *p_dir = NULL; 1109 struct exfat_uni_name uni_name; 1110 struct exfat_dentry *ep; 1111 struct super_block *sb = old_parent_inode->i_sb; 1112 struct exfat_sb_info *sbi = EXFAT_SB(sb); 1113 const unsigned char *new_path = new_dentry->d_name.name; 1114 struct inode *new_inode = new_dentry->d_inode; 1115 struct exfat_inode_info *new_ei = NULL; 1116 unsigned int new_entry_type = TYPE_UNUSED; 1117 int new_entry = 0; 1118 struct buffer_head *new_bh = NULL; 1119 1120 /* check the validity of pointer parameters */ 1121 if (new_path == NULL || strlen(new_path) == 0) 1122 return -EINVAL; 1123 1124 if (ei->dir.dir == DIR_DELETED) { 1125 exfat_err(sb, "abnormal access to deleted source dentry"); 1126 return -ENOENT; 1127 } 1128 1129 exfat_chain_set(&olddir, EXFAT_I(old_parent_inode)->start_clu, 1130 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(old_parent_inode), sbi), 1131 EXFAT_I(old_parent_inode)->flags); 1132 dentry = ei->entry; 1133 1134 /* check whether new dir is existing directory and empty */ 1135 if (new_inode) { 1136 ret = -EIO; 1137 new_ei = EXFAT_I(new_inode); 1138 1139 if (new_ei->dir.dir == DIR_DELETED) { 1140 exfat_err(sb, "abnormal access to deleted target dentry"); 1141 goto out; 1142 } 1143 1144 p_dir = &(new_ei->dir); 1145 new_entry = new_ei->entry; 1146 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh); 1147 if (!ep) 1148 goto out; 1149 1150 new_entry_type = exfat_get_entry_type(ep); 1151 brelse(new_bh); 1152 1153 /* if new_inode exists, update ei */ 1154 if (new_entry_type == TYPE_DIR) { 1155 struct exfat_chain new_clu; 1156 1157 new_clu.dir = new_ei->start_clu; 1158 new_clu.size = 1159 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1160 sbi); 1161 new_clu.flags = new_ei->flags; 1162 1163 ret = exfat_check_dir_empty(sb, &new_clu); 1164 if (ret) 1165 goto out; 1166 } 1167 } 1168 1169 /* check the validity of directory name in the given new pathname */ 1170 ret = exfat_resolve_path(new_parent_inode, new_path, &newdir, 1171 &uni_name); 1172 if (ret) 1173 goto out; 1174 1175 exfat_set_volume_dirty(sb); 1176 1177 if (olddir.dir == newdir.dir) 1178 ret = exfat_rename_file(new_parent_inode, &olddir, dentry, 1179 &uni_name, ei); 1180 else 1181 ret = exfat_move_file(new_parent_inode, &olddir, dentry, 1182 &newdir, &uni_name, ei); 1183 1184 if (!ret && new_inode) { 1185 struct exfat_entry_set_cache es; 1186 1187 /* delete entries of new_dir */ 1188 ret = exfat_get_dentry_set(&es, sb, p_dir, new_entry, 1189 ES_ALL_ENTRIES); 1190 if (ret) { 1191 ret = -EIO; 1192 goto del_out; 1193 } 1194 1195 exfat_remove_entries(new_inode, &es, ES_IDX_FILE); 1196 1197 ret = exfat_put_dentry_set(&es, IS_DIRSYNC(new_inode)); 1198 if (ret) 1199 goto del_out; 1200 1201 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */ 1202 if (new_entry_type == TYPE_DIR && 1203 new_ei->start_clu != EXFAT_EOF_CLUSTER) { 1204 /* new_ei, new_clu_to_free */ 1205 struct exfat_chain new_clu_to_free; 1206 1207 exfat_chain_set(&new_clu_to_free, new_ei->start_clu, 1208 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode), 1209 sbi), new_ei->flags); 1210 1211 if (exfat_free_cluster(new_inode, &new_clu_to_free)) { 1212 /* just set I/O error only */ 1213 ret = -EIO; 1214 } 1215 1216 i_size_write(new_inode, 0); 1217 new_ei->valid_size = 0; 1218 new_ei->start_clu = EXFAT_EOF_CLUSTER; 1219 new_ei->flags = ALLOC_NO_FAT_CHAIN; 1220 } 1221del_out: 1222 /* Update new_inode ei 1223 * Prevent syncing removed new_inode 1224 * (new_ei is already initialized above code ("if (new_inode)") 1225 */ 1226 new_ei->dir.dir = DIR_DELETED; 1227 } 1228out: 1229 return ret; 1230} 1231 1232static int exfat_rename(struct mnt_idmap *idmap, 1233 struct inode *old_dir, struct dentry *old_dentry, 1234 struct inode *new_dir, struct dentry *new_dentry, 1235 unsigned int flags) 1236{ 1237 struct inode *old_inode, *new_inode; 1238 struct super_block *sb = old_dir->i_sb; 1239 loff_t i_pos; 1240 int err; 1241 loff_t size = i_size_read(new_dir); 1242 1243 /* 1244 * The VFS already checks for existence, so for local filesystems 1245 * the RENAME_NOREPLACE implementation is equivalent to plain rename. 1246 * Don't support any other flags 1247 */ 1248 if (flags & ~RENAME_NOREPLACE) 1249 return -EINVAL; 1250 1251 mutex_lock(&EXFAT_SB(sb)->s_lock); 1252 old_inode = old_dentry->d_inode; 1253 new_inode = new_dentry->d_inode; 1254 1255 err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry); 1256 if (err) 1257 goto unlock; 1258 1259 inode_inc_iversion(new_dir); 1260 simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry); 1261 EXFAT_I(new_dir)->i_crtime = current_time(new_dir); 1262 exfat_truncate_inode_atime(new_dir); 1263 if (IS_DIRSYNC(new_dir) && size != i_size_read(new_dir)) 1264 exfat_sync_inode(new_dir); 1265 else 1266 mark_inode_dirty(new_dir); 1267 1268 i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) | 1269 (EXFAT_I(old_inode)->entry & 0xffffffff); 1270 exfat_unhash_inode(old_inode); 1271 exfat_hash_inode(old_inode, i_pos); 1272 if (IS_DIRSYNC(new_dir)) 1273 exfat_sync_inode(old_inode); 1274 else 1275 mark_inode_dirty(old_inode); 1276 1277 if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) { 1278 drop_nlink(old_dir); 1279 if (!new_inode) 1280 inc_nlink(new_dir); 1281 } 1282 1283 inode_inc_iversion(old_dir); 1284 if (new_dir != old_dir) 1285 mark_inode_dirty(old_dir); 1286 1287 if (new_inode) { 1288 exfat_unhash_inode(new_inode); 1289 1290 /* skip drop_nlink if new_inode already has been dropped */ 1291 if (new_inode->i_nlink) { 1292 drop_nlink(new_inode); 1293 if (S_ISDIR(new_inode->i_mode)) 1294 drop_nlink(new_inode); 1295 } else { 1296 exfat_warn(sb, "abnormal access to an inode dropped"); 1297 WARN_ON(new_inode->i_nlink == 0); 1298 } 1299 EXFAT_I(new_inode)->i_crtime = current_time(new_inode); 1300 } 1301 1302unlock: 1303 mutex_unlock(&EXFAT_SB(sb)->s_lock); 1304 return err; 1305} 1306 1307const struct inode_operations exfat_dir_inode_operations = { 1308 .create = exfat_create, 1309 .lookup = exfat_lookup, 1310 .unlink = exfat_unlink, 1311 .mkdir = exfat_mkdir, 1312 .rmdir = exfat_rmdir, 1313 .rename = exfat_rename, 1314 .setattr = exfat_setattr, 1315 .getattr = exfat_getattr, 1316}; 1317