1 /* 2 * fs/f2fs/dir.c 3 * 4 * Copyright (c) 2012 Samsung Electronics Co., Ltd. 5 * http://www.samsung.com/ 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 #include <linux/fs.h> 12 #include <linux/f2fs_fs.h> 13 #include "f2fs.h" 14 #include "node.h" 15 #include "acl.h" 16 #include "xattr.h" 17 18 static unsigned long dir_blocks(struct inode *inode) 19 { 20 return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1)) 21 >> PAGE_SHIFT; 22 } 23 24 static unsigned int dir_buckets(unsigned int level, int dir_level) 25 { 26 if (level + dir_level < MAX_DIR_HASH_DEPTH / 2) 27 return 1 << (level + dir_level); 28 else 29 return MAX_DIR_BUCKETS; 30 } 31 32 static unsigned int bucket_blocks(unsigned int level) 33 { 34 if (level < MAX_DIR_HASH_DEPTH / 2) 35 return 2; 36 else 37 return 4; 38 } 39 40 unsigned char f2fs_filetype_table[F2FS_FT_MAX] = { 41 [F2FS_FT_UNKNOWN] = DT_UNKNOWN, 42 [F2FS_FT_REG_FILE] = DT_REG, 43 [F2FS_FT_DIR] = DT_DIR, 44 [F2FS_FT_CHRDEV] = DT_CHR, 45 [F2FS_FT_BLKDEV] = DT_BLK, 46 [F2FS_FT_FIFO] = DT_FIFO, 47 [F2FS_FT_SOCK] = DT_SOCK, 48 [F2FS_FT_SYMLINK] = DT_LNK, 49 }; 50 51 #define S_SHIFT 12 52 static unsigned char f2fs_type_by_mode[S_IFMT >> S_SHIFT] = { 53 [S_IFREG >> S_SHIFT] = F2FS_FT_REG_FILE, 54 [S_IFDIR >> S_SHIFT] = F2FS_FT_DIR, 55 [S_IFCHR >> S_SHIFT] = F2FS_FT_CHRDEV, 56 [S_IFBLK >> S_SHIFT] = F2FS_FT_BLKDEV, 57 [S_IFIFO >> S_SHIFT] = F2FS_FT_FIFO, 58 [S_IFSOCK >> S_SHIFT] = F2FS_FT_SOCK, 59 [S_IFLNK >> S_SHIFT] = F2FS_FT_SYMLINK, 60 }; 61 62 void set_de_type(struct f2fs_dir_entry *de, umode_t mode) 63 { 64 de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT]; 65 } 66 67 static unsigned long dir_block_index(unsigned int level, 68 int dir_level, unsigned int idx) 69 { 70 unsigned long i; 71 unsigned long bidx = 0; 72 73 for (i = 0; i < level; i++) 74 bidx += dir_buckets(i, dir_level) * bucket_blocks(i); 75 bidx += idx * bucket_blocks(level); 76 return bidx; 77 } 78 79 static struct f2fs_dir_entry *find_in_block(struct page *dentry_page, 80 struct fscrypt_name *fname, 81 f2fs_hash_t namehash, 82 int *max_slots, 83 struct page **res_page) 84 { 85 struct f2fs_dentry_block *dentry_blk; 86 struct f2fs_dir_entry *de; 87 struct f2fs_dentry_ptr d; 88 89 dentry_blk = (struct f2fs_dentry_block *)kmap(dentry_page); 90 91 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1); 92 de = find_target_dentry(fname, namehash, max_slots, &d); 93 if (de) 94 *res_page = dentry_page; 95 else 96 kunmap(dentry_page); 97 98 /* 99 * For the most part, it should be a bug when name_len is zero. 100 * We stop here for figuring out where the bugs has occurred. 101 */ 102 f2fs_bug_on(F2FS_P_SB(dentry_page), d.max < 0); 103 return de; 104 } 105 106 struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *fname, 107 f2fs_hash_t namehash, int *max_slots, 108 struct f2fs_dentry_ptr *d) 109 { 110 struct f2fs_dir_entry *de; 111 unsigned long bit_pos = 0; 112 int max_len = 0; 113 struct fscrypt_str de_name = FSTR_INIT(NULL, 0); 114 struct fscrypt_str *name = &fname->disk_name; 115 116 if (max_slots) 117 *max_slots = 0; 118 while (bit_pos < d->max) { 119 if (!test_bit_le(bit_pos, d->bitmap)) { 120 bit_pos++; 121 max_len++; 122 continue; 123 } 124 125 de = &d->dentry[bit_pos]; 126 127 /* encrypted case */ 128 de_name.name = d->filename[bit_pos]; 129 de_name.len = le16_to_cpu(de->name_len); 130 131 /* show encrypted name */ 132 if (fname->hash) { 133 if (de->hash_code == fname->hash) 134 goto found; 135 } else if (de_name.len == name->len && 136 de->hash_code == namehash && 137 !memcmp(de_name.name, name->name, name->len)) 138 goto found; 139 140 if (max_slots && max_len > *max_slots) 141 *max_slots = max_len; 142 max_len = 0; 143 144 /* remain bug on condition */ 145 if (unlikely(!de->name_len)) 146 d->max = -1; 147 148 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); 149 } 150 151 de = NULL; 152 found: 153 if (max_slots && max_len > *max_slots) 154 *max_slots = max_len; 155 return de; 156 } 157 158 static struct f2fs_dir_entry *find_in_level(struct inode *dir, 159 unsigned int level, 160 struct fscrypt_name *fname, 161 struct page **res_page) 162 { 163 struct qstr name = FSTR_TO_QSTR(&fname->disk_name); 164 int s = GET_DENTRY_SLOTS(name.len); 165 unsigned int nbucket, nblock; 166 unsigned int bidx, end_block; 167 struct page *dentry_page; 168 struct f2fs_dir_entry *de = NULL; 169 bool room = false; 170 int max_slots; 171 f2fs_hash_t namehash; 172 173 namehash = f2fs_dentry_hash(&name); 174 175 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level); 176 nblock = bucket_blocks(level); 177 178 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level, 179 le32_to_cpu(namehash) % nbucket); 180 end_block = bidx + nblock; 181 182 for (; bidx < end_block; bidx++) { 183 /* no need to allocate new dentry pages to all the indices */ 184 dentry_page = find_data_page(dir, bidx); 185 if (IS_ERR(dentry_page)) { 186 room = true; 187 continue; 188 } 189 190 de = find_in_block(dentry_page, fname, namehash, &max_slots, 191 res_page); 192 if (de) 193 break; 194 195 if (max_slots >= s) 196 room = true; 197 f2fs_put_page(dentry_page, 0); 198 } 199 200 if (!de && room && F2FS_I(dir)->chash != namehash) { 201 F2FS_I(dir)->chash = namehash; 202 F2FS_I(dir)->clevel = level; 203 } 204 205 return de; 206 } 207 208 /* 209 * Find an entry in the specified directory with the wanted name. 210 * It returns the page where the entry was found (as a parameter - res_page), 211 * and the entry itself. Page is returned mapped and unlocked. 212 * Entry is guaranteed to be valid. 213 */ 214 struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir, 215 struct qstr *child, struct page **res_page) 216 { 217 unsigned long npages = dir_blocks(dir); 218 struct f2fs_dir_entry *de = NULL; 219 unsigned int max_depth; 220 unsigned int level; 221 struct fscrypt_name fname; 222 int err; 223 224 *res_page = NULL; 225 226 err = fscrypt_setup_filename(dir, child, 1, &fname); 227 if (err) 228 return NULL; 229 230 if (f2fs_has_inline_dentry(dir)) { 231 de = find_in_inline_dir(dir, &fname, res_page); 232 goto out; 233 } 234 235 if (npages == 0) 236 goto out; 237 238 max_depth = F2FS_I(dir)->i_current_depth; 239 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) { 240 f2fs_msg(F2FS_I_SB(dir)->sb, KERN_WARNING, 241 "Corrupted max_depth of %lu: %u", 242 dir->i_ino, max_depth); 243 max_depth = MAX_DIR_HASH_DEPTH; 244 F2FS_I(dir)->i_current_depth = max_depth; 245 mark_inode_dirty(dir); 246 } 247 248 for (level = 0; level < max_depth; level++) { 249 de = find_in_level(dir, level, &fname, res_page); 250 if (de) 251 break; 252 } 253 out: 254 fscrypt_free_filename(&fname); 255 return de; 256 } 257 258 struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p) 259 { 260 struct page *page; 261 struct f2fs_dir_entry *de; 262 struct f2fs_dentry_block *dentry_blk; 263 264 if (f2fs_has_inline_dentry(dir)) 265 return f2fs_parent_inline_dir(dir, p); 266 267 page = get_lock_data_page(dir, 0, false); 268 if (IS_ERR(page)) 269 return NULL; 270 271 dentry_blk = kmap(page); 272 de = &dentry_blk->dentry[1]; 273 *p = page; 274 unlock_page(page); 275 return de; 276 } 277 278 ino_t f2fs_inode_by_name(struct inode *dir, struct qstr *qstr) 279 { 280 ino_t res = 0; 281 struct f2fs_dir_entry *de; 282 struct page *page; 283 284 de = f2fs_find_entry(dir, qstr, &page); 285 if (de) { 286 res = le32_to_cpu(de->ino); 287 f2fs_dentry_kunmap(dir, page); 288 f2fs_put_page(page, 0); 289 } 290 291 return res; 292 } 293 294 void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de, 295 struct page *page, struct inode *inode) 296 { 297 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA; 298 lock_page(page); 299 f2fs_wait_on_page_writeback(page, type, true); 300 de->ino = cpu_to_le32(inode->i_ino); 301 set_de_type(de, inode->i_mode); 302 f2fs_dentry_kunmap(dir, page); 303 set_page_dirty(page); 304 dir->i_mtime = dir->i_ctime = CURRENT_TIME; 305 mark_inode_dirty(dir); 306 307 f2fs_put_page(page, 1); 308 } 309 310 static void init_dent_inode(const struct qstr *name, struct page *ipage) 311 { 312 struct f2fs_inode *ri; 313 314 f2fs_wait_on_page_writeback(ipage, NODE, true); 315 316 /* copy name info. to this inode page */ 317 ri = F2FS_INODE(ipage); 318 ri->i_namelen = cpu_to_le32(name->len); 319 memcpy(ri->i_name, name->name, name->len); 320 set_page_dirty(ipage); 321 } 322 323 int update_dent_inode(struct inode *inode, struct inode *to, 324 const struct qstr *name) 325 { 326 struct page *page; 327 328 if (file_enc_name(to)) 329 return 0; 330 331 page = get_node_page(F2FS_I_SB(inode), inode->i_ino); 332 if (IS_ERR(page)) 333 return PTR_ERR(page); 334 335 init_dent_inode(name, page); 336 f2fs_put_page(page, 1); 337 338 return 0; 339 } 340 341 void do_make_empty_dir(struct inode *inode, struct inode *parent, 342 struct f2fs_dentry_ptr *d) 343 { 344 struct qstr dot = QSTR_INIT(".", 1); 345 struct qstr dotdot = QSTR_INIT("..", 2); 346 347 /* update dirent of "." */ 348 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0); 349 350 /* update dirent of ".." */ 351 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1); 352 } 353 354 static int make_empty_dir(struct inode *inode, 355 struct inode *parent, struct page *page) 356 { 357 struct page *dentry_page; 358 struct f2fs_dentry_block *dentry_blk; 359 struct f2fs_dentry_ptr d; 360 361 if (f2fs_has_inline_dentry(inode)) 362 return make_empty_inline_dir(inode, parent, page); 363 364 dentry_page = get_new_data_page(inode, page, 0, true); 365 if (IS_ERR(dentry_page)) 366 return PTR_ERR(dentry_page); 367 368 dentry_blk = kmap_atomic(dentry_page); 369 370 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1); 371 do_make_empty_dir(inode, parent, &d); 372 373 kunmap_atomic(dentry_blk); 374 375 set_page_dirty(dentry_page); 376 f2fs_put_page(dentry_page, 1); 377 return 0; 378 } 379 380 struct page *init_inode_metadata(struct inode *inode, struct inode *dir, 381 const struct qstr *name, struct page *dpage) 382 { 383 struct page *page; 384 int err; 385 386 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) { 387 page = new_inode_page(inode); 388 if (IS_ERR(page)) 389 return page; 390 391 if (S_ISDIR(inode->i_mode)) { 392 err = make_empty_dir(inode, dir, page); 393 if (err) 394 goto error; 395 } 396 397 err = f2fs_init_acl(inode, dir, page, dpage); 398 if (err) 399 goto put_error; 400 401 err = f2fs_init_security(inode, dir, name, page); 402 if (err) 403 goto put_error; 404 405 if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) { 406 err = fscrypt_inherit_context(dir, inode, page, false); 407 if (err) 408 goto put_error; 409 } 410 } else { 411 page = get_node_page(F2FS_I_SB(dir), inode->i_ino); 412 if (IS_ERR(page)) 413 return page; 414 415 set_cold_node(inode, page); 416 } 417 418 if (name) 419 init_dent_inode(name, page); 420 421 /* 422 * This file should be checkpointed during fsync. 423 * We lost i_pino from now on. 424 */ 425 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) { 426 file_lost_pino(inode); 427 /* 428 * If link the tmpfile to alias through linkat path, 429 * we should remove this inode from orphan list. 430 */ 431 if (inode->i_nlink == 0) 432 remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino); 433 inc_nlink(inode); 434 } 435 return page; 436 437 put_error: 438 f2fs_put_page(page, 1); 439 error: 440 /* once the failed inode becomes a bad inode, i_mode is S_IFREG */ 441 truncate_inode_pages(&inode->i_data, 0); 442 truncate_blocks(inode, 0, false); 443 remove_dirty_inode(inode); 444 remove_inode_page(inode); 445 return ERR_PTR(err); 446 } 447 448 void update_parent_metadata(struct inode *dir, struct inode *inode, 449 unsigned int current_depth) 450 { 451 if (inode && is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) { 452 if (S_ISDIR(inode->i_mode)) { 453 inc_nlink(dir); 454 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 455 } 456 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE); 457 } 458 dir->i_mtime = dir->i_ctime = CURRENT_TIME; 459 mark_inode_dirty(dir); 460 461 if (F2FS_I(dir)->i_current_depth != current_depth) { 462 F2FS_I(dir)->i_current_depth = current_depth; 463 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 464 } 465 466 if (inode && is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) 467 clear_inode_flag(F2FS_I(inode), FI_INC_LINK); 468 } 469 470 int room_for_filename(const void *bitmap, int slots, int max_slots) 471 { 472 int bit_start = 0; 473 int zero_start, zero_end; 474 next: 475 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start); 476 if (zero_start >= max_slots) 477 return max_slots; 478 479 zero_end = find_next_bit_le(bitmap, max_slots, zero_start); 480 if (zero_end - zero_start >= slots) 481 return zero_start; 482 483 bit_start = zero_end + 1; 484 485 if (zero_end + 1 >= max_slots) 486 return max_slots; 487 goto next; 488 } 489 490 void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d, 491 const struct qstr *name, f2fs_hash_t name_hash, 492 unsigned int bit_pos) 493 { 494 struct f2fs_dir_entry *de; 495 int slots = GET_DENTRY_SLOTS(name->len); 496 int i; 497 498 de = &d->dentry[bit_pos]; 499 de->hash_code = name_hash; 500 de->name_len = cpu_to_le16(name->len); 501 memcpy(d->filename[bit_pos], name->name, name->len); 502 de->ino = cpu_to_le32(ino); 503 set_de_type(de, mode); 504 for (i = 0; i < slots; i++) { 505 test_and_set_bit_le(bit_pos + i, (void *)d->bitmap); 506 /* avoid wrong garbage data for readdir */ 507 if (i) 508 (de + i)->name_len = 0; 509 } 510 } 511 512 /* 513 * Caller should grab and release a rwsem by calling f2fs_lock_op() and 514 * f2fs_unlock_op(). 515 */ 516 int __f2fs_add_link(struct inode *dir, const struct qstr *name, 517 struct inode *inode, nid_t ino, umode_t mode) 518 { 519 unsigned int bit_pos; 520 unsigned int level; 521 unsigned int current_depth; 522 unsigned long bidx, block; 523 f2fs_hash_t dentry_hash; 524 unsigned int nbucket, nblock; 525 struct page *dentry_page = NULL; 526 struct f2fs_dentry_block *dentry_blk = NULL; 527 struct f2fs_dentry_ptr d; 528 struct page *page = NULL; 529 struct fscrypt_name fname; 530 struct qstr new_name; 531 int slots, err; 532 533 err = fscrypt_setup_filename(dir, name, 0, &fname); 534 if (err) 535 return err; 536 537 new_name.name = fname_name(&fname); 538 new_name.len = fname_len(&fname); 539 540 if (f2fs_has_inline_dentry(dir)) { 541 err = f2fs_add_inline_entry(dir, &new_name, inode, ino, mode); 542 if (!err || err != -EAGAIN) 543 goto out; 544 else 545 err = 0; 546 } 547 548 level = 0; 549 slots = GET_DENTRY_SLOTS(new_name.len); 550 dentry_hash = f2fs_dentry_hash(&new_name); 551 552 current_depth = F2FS_I(dir)->i_current_depth; 553 if (F2FS_I(dir)->chash == dentry_hash) { 554 level = F2FS_I(dir)->clevel; 555 F2FS_I(dir)->chash = 0; 556 } 557 558 start: 559 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH)) { 560 err = -ENOSPC; 561 goto out; 562 } 563 564 /* Increase the depth, if required */ 565 if (level == current_depth) 566 ++current_depth; 567 568 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level); 569 nblock = bucket_blocks(level); 570 571 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level, 572 (le32_to_cpu(dentry_hash) % nbucket)); 573 574 for (block = bidx; block <= (bidx + nblock - 1); block++) { 575 dentry_page = get_new_data_page(dir, NULL, block, true); 576 if (IS_ERR(dentry_page)) { 577 err = PTR_ERR(dentry_page); 578 goto out; 579 } 580 581 dentry_blk = kmap(dentry_page); 582 bit_pos = room_for_filename(&dentry_blk->dentry_bitmap, 583 slots, NR_DENTRY_IN_BLOCK); 584 if (bit_pos < NR_DENTRY_IN_BLOCK) 585 goto add_dentry; 586 587 kunmap(dentry_page); 588 f2fs_put_page(dentry_page, 1); 589 } 590 591 /* Move to next level to find the empty slot for new dentry */ 592 ++level; 593 goto start; 594 add_dentry: 595 f2fs_wait_on_page_writeback(dentry_page, DATA, true); 596 597 if (inode) { 598 down_write(&F2FS_I(inode)->i_sem); 599 page = init_inode_metadata(inode, dir, &new_name, NULL); 600 if (IS_ERR(page)) { 601 err = PTR_ERR(page); 602 goto fail; 603 } 604 if (f2fs_encrypted_inode(dir)) 605 file_set_enc_name(inode); 606 } 607 608 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1); 609 f2fs_update_dentry(ino, mode, &d, &new_name, dentry_hash, bit_pos); 610 611 set_page_dirty(dentry_page); 612 613 if (inode) { 614 /* we don't need to mark_inode_dirty now */ 615 F2FS_I(inode)->i_pino = dir->i_ino; 616 update_inode(inode, page); 617 f2fs_put_page(page, 1); 618 } 619 620 update_parent_metadata(dir, inode, current_depth); 621 fail: 622 if (inode) 623 up_write(&F2FS_I(inode)->i_sem); 624 625 if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) { 626 update_inode_page(dir); 627 clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 628 } 629 kunmap(dentry_page); 630 f2fs_put_page(dentry_page, 1); 631 out: 632 fscrypt_free_filename(&fname); 633 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME); 634 return err; 635 } 636 637 int f2fs_do_tmpfile(struct inode *inode, struct inode *dir) 638 { 639 struct page *page; 640 int err = 0; 641 642 down_write(&F2FS_I(inode)->i_sem); 643 page = init_inode_metadata(inode, dir, NULL, NULL); 644 if (IS_ERR(page)) { 645 err = PTR_ERR(page); 646 goto fail; 647 } 648 /* we don't need to mark_inode_dirty now */ 649 update_inode(inode, page); 650 f2fs_put_page(page, 1); 651 652 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE); 653 fail: 654 up_write(&F2FS_I(inode)->i_sem); 655 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME); 656 return err; 657 } 658 659 void f2fs_drop_nlink(struct inode *dir, struct inode *inode, struct page *page) 660 { 661 struct f2fs_sb_info *sbi = F2FS_I_SB(dir); 662 663 down_write(&F2FS_I(inode)->i_sem); 664 665 if (S_ISDIR(inode->i_mode)) { 666 drop_nlink(dir); 667 if (page) 668 update_inode(dir, page); 669 else 670 update_inode_page(dir); 671 } 672 inode->i_ctime = CURRENT_TIME; 673 674 drop_nlink(inode); 675 if (S_ISDIR(inode->i_mode)) { 676 drop_nlink(inode); 677 i_size_write(inode, 0); 678 } 679 up_write(&F2FS_I(inode)->i_sem); 680 update_inode_page(inode); 681 682 if (inode->i_nlink == 0) 683 add_orphan_inode(sbi, inode->i_ino); 684 else 685 release_orphan_inode(sbi); 686 } 687 688 /* 689 * It only removes the dentry from the dentry page, corresponding name 690 * entry in name page does not need to be touched during deletion. 691 */ 692 void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page, 693 struct inode *dir, struct inode *inode) 694 { 695 struct f2fs_dentry_block *dentry_blk; 696 unsigned int bit_pos; 697 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len)); 698 int i; 699 700 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME); 701 702 if (f2fs_has_inline_dentry(dir)) 703 return f2fs_delete_inline_entry(dentry, page, dir, inode); 704 705 lock_page(page); 706 f2fs_wait_on_page_writeback(page, DATA, true); 707 708 dentry_blk = page_address(page); 709 bit_pos = dentry - dentry_blk->dentry; 710 for (i = 0; i < slots; i++) 711 clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap); 712 713 /* Let's check and deallocate this dentry page */ 714 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap, 715 NR_DENTRY_IN_BLOCK, 716 0); 717 kunmap(page); /* kunmap - pair of f2fs_find_entry */ 718 set_page_dirty(page); 719 720 dir->i_ctime = dir->i_mtime = CURRENT_TIME; 721 722 if (inode) 723 f2fs_drop_nlink(dir, inode, NULL); 724 725 if (bit_pos == NR_DENTRY_IN_BLOCK && 726 !truncate_hole(dir, page->index, page->index + 1)) { 727 clear_page_dirty_for_io(page); 728 ClearPagePrivate(page); 729 ClearPageUptodate(page); 730 inode_dec_dirty_pages(dir); 731 } 732 f2fs_put_page(page, 1); 733 } 734 735 bool f2fs_empty_dir(struct inode *dir) 736 { 737 unsigned long bidx; 738 struct page *dentry_page; 739 unsigned int bit_pos; 740 struct f2fs_dentry_block *dentry_blk; 741 unsigned long nblock = dir_blocks(dir); 742 743 if (f2fs_has_inline_dentry(dir)) 744 return f2fs_empty_inline_dir(dir); 745 746 for (bidx = 0; bidx < nblock; bidx++) { 747 dentry_page = get_lock_data_page(dir, bidx, false); 748 if (IS_ERR(dentry_page)) { 749 if (PTR_ERR(dentry_page) == -ENOENT) 750 continue; 751 else 752 return false; 753 } 754 755 dentry_blk = kmap_atomic(dentry_page); 756 if (bidx == 0) 757 bit_pos = 2; 758 else 759 bit_pos = 0; 760 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap, 761 NR_DENTRY_IN_BLOCK, 762 bit_pos); 763 kunmap_atomic(dentry_blk); 764 765 f2fs_put_page(dentry_page, 1); 766 767 if (bit_pos < NR_DENTRY_IN_BLOCK) 768 return false; 769 } 770 return true; 771 } 772 773 bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, 774 unsigned int start_pos, struct fscrypt_str *fstr) 775 { 776 unsigned char d_type = DT_UNKNOWN; 777 unsigned int bit_pos; 778 struct f2fs_dir_entry *de = NULL; 779 struct fscrypt_str de_name = FSTR_INIT(NULL, 0); 780 781 bit_pos = ((unsigned long)ctx->pos % d->max); 782 783 while (bit_pos < d->max) { 784 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos); 785 if (bit_pos >= d->max) 786 break; 787 788 de = &d->dentry[bit_pos]; 789 if (de->name_len == 0) { 790 bit_pos++; 791 ctx->pos = start_pos + bit_pos; 792 continue; 793 } 794 795 if (de->file_type < F2FS_FT_MAX) 796 d_type = f2fs_filetype_table[de->file_type]; 797 else 798 d_type = DT_UNKNOWN; 799 800 de_name.name = d->filename[bit_pos]; 801 de_name.len = le16_to_cpu(de->name_len); 802 803 if (f2fs_encrypted_inode(d->inode)) { 804 int save_len = fstr->len; 805 int ret; 806 807 de_name.name = kmalloc(de_name.len, GFP_NOFS); 808 if (!de_name.name) 809 return false; 810 811 memcpy(de_name.name, d->filename[bit_pos], de_name.len); 812 813 ret = fscrypt_fname_disk_to_usr(d->inode, 814 (u32)de->hash_code, 0, 815 &de_name, fstr); 816 kfree(de_name.name); 817 if (ret < 0) 818 return true; 819 820 de_name = *fstr; 821 fstr->len = save_len; 822 } 823 824 if (!dir_emit(ctx, de_name.name, de_name.len, 825 le32_to_cpu(de->ino), d_type)) 826 return true; 827 828 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); 829 ctx->pos = start_pos + bit_pos; 830 } 831 return false; 832 } 833 834 static int f2fs_readdir(struct file *file, struct dir_context *ctx) 835 { 836 struct inode *inode = file_inode(file); 837 unsigned long npages = dir_blocks(inode); 838 struct f2fs_dentry_block *dentry_blk = NULL; 839 struct page *dentry_page = NULL; 840 struct file_ra_state *ra = &file->f_ra; 841 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK); 842 struct f2fs_dentry_ptr d; 843 struct fscrypt_str fstr = FSTR_INIT(NULL, 0); 844 int err = 0; 845 846 if (f2fs_encrypted_inode(inode)) { 847 err = fscrypt_get_encryption_info(inode); 848 if (err && err != -ENOKEY) 849 return err; 850 851 err = fscrypt_fname_alloc_buffer(inode, F2FS_NAME_LEN, &fstr); 852 if (err < 0) 853 return err; 854 } 855 856 if (f2fs_has_inline_dentry(inode)) { 857 err = f2fs_read_inline_dir(file, ctx, &fstr); 858 goto out; 859 } 860 861 /* readahead for multi pages of dir */ 862 if (npages - n > 1 && !ra_has_index(ra, n)) 863 page_cache_sync_readahead(inode->i_mapping, ra, file, n, 864 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES)); 865 866 for (; n < npages; n++) { 867 dentry_page = get_lock_data_page(inode, n, false); 868 if (IS_ERR(dentry_page)) { 869 err = PTR_ERR(dentry_page); 870 if (err == -ENOENT) 871 continue; 872 else 873 goto out; 874 } 875 876 dentry_blk = kmap(dentry_page); 877 878 make_dentry_ptr(inode, &d, (void *)dentry_blk, 1); 879 880 if (f2fs_fill_dentries(ctx, &d, n * NR_DENTRY_IN_BLOCK, &fstr)) { 881 kunmap(dentry_page); 882 f2fs_put_page(dentry_page, 1); 883 break; 884 } 885 886 ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK; 887 kunmap(dentry_page); 888 f2fs_put_page(dentry_page, 1); 889 } 890 out: 891 fscrypt_fname_free_buffer(&fstr); 892 return err; 893 } 894 895 static int f2fs_dir_open(struct inode *inode, struct file *filp) 896 { 897 if (f2fs_encrypted_inode(inode)) 898 return fscrypt_get_encryption_info(inode) ? -EACCES : 0; 899 return 0; 900 } 901 902 const struct file_operations f2fs_dir_operations = { 903 .llseek = generic_file_llseek, 904 .read = generic_read_dir, 905 .iterate = f2fs_readdir, 906 .fsync = f2fs_sync_file, 907 .open = f2fs_dir_open, 908 .unlocked_ioctl = f2fs_ioctl, 909 #ifdef CONFIG_COMPAT 910 .compat_ioctl = f2fs_compat_ioctl, 911 #endif 912 }; 913