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_CACHE_SIZE - 1)) 21 >> PAGE_CACHE_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 f2fs_filename *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 f2fs_filename *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 f2fs_str de_name = FSTR_INIT(NULL, 0); 114 struct f2fs_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 f2fs_filename *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 f2fs_bug_on(F2FS_I_SB(dir), level > MAX_DIR_HASH_DEPTH); 176 177 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level); 178 nblock = bucket_blocks(level); 179 180 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level, 181 le32_to_cpu(namehash) % nbucket); 182 end_block = bidx + nblock; 183 184 for (; bidx < end_block; bidx++) { 185 /* no need to allocate new dentry pages to all the indices */ 186 dentry_page = find_data_page(dir, bidx); 187 if (IS_ERR(dentry_page)) { 188 room = true; 189 continue; 190 } 191 192 de = find_in_block(dentry_page, fname, namehash, &max_slots, 193 res_page); 194 if (de) 195 break; 196 197 if (max_slots >= s) 198 room = true; 199 f2fs_put_page(dentry_page, 0); 200 } 201 202 if (!de && room && F2FS_I(dir)->chash != namehash) { 203 F2FS_I(dir)->chash = namehash; 204 F2FS_I(dir)->clevel = level; 205 } 206 207 return de; 208 } 209 210 /* 211 * Find an entry in the specified directory with the wanted name. 212 * It returns the page where the entry was found (as a parameter - res_page), 213 * and the entry itself. Page is returned mapped and unlocked. 214 * Entry is guaranteed to be valid. 215 */ 216 struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir, 217 struct qstr *child, struct page **res_page) 218 { 219 unsigned long npages = dir_blocks(dir); 220 struct f2fs_dir_entry *de = NULL; 221 unsigned int max_depth; 222 unsigned int level; 223 struct f2fs_filename fname; 224 int err; 225 226 *res_page = NULL; 227 228 err = f2fs_fname_setup_filename(dir, child, 1, &fname); 229 if (err) 230 return NULL; 231 232 if (f2fs_has_inline_dentry(dir)) { 233 de = find_in_inline_dir(dir, &fname, res_page); 234 goto out; 235 } 236 237 if (npages == 0) 238 goto out; 239 240 max_depth = F2FS_I(dir)->i_current_depth; 241 242 for (level = 0; level < max_depth; level++) { 243 de = find_in_level(dir, level, &fname, res_page); 244 if (de) 245 break; 246 } 247 out: 248 f2fs_fname_free_filename(&fname); 249 return de; 250 } 251 252 struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p) 253 { 254 struct page *page; 255 struct f2fs_dir_entry *de; 256 struct f2fs_dentry_block *dentry_blk; 257 258 if (f2fs_has_inline_dentry(dir)) 259 return f2fs_parent_inline_dir(dir, p); 260 261 page = get_lock_data_page(dir, 0); 262 if (IS_ERR(page)) 263 return NULL; 264 265 dentry_blk = kmap(page); 266 de = &dentry_blk->dentry[1]; 267 *p = page; 268 unlock_page(page); 269 return de; 270 } 271 272 ino_t f2fs_inode_by_name(struct inode *dir, struct qstr *qstr) 273 { 274 ino_t res = 0; 275 struct f2fs_dir_entry *de; 276 struct page *page; 277 278 de = f2fs_find_entry(dir, qstr, &page); 279 if (de) { 280 res = le32_to_cpu(de->ino); 281 f2fs_dentry_kunmap(dir, page); 282 f2fs_put_page(page, 0); 283 } 284 285 return res; 286 } 287 288 void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de, 289 struct page *page, struct inode *inode) 290 { 291 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA; 292 lock_page(page); 293 f2fs_wait_on_page_writeback(page, type); 294 de->ino = cpu_to_le32(inode->i_ino); 295 set_de_type(de, inode->i_mode); 296 f2fs_dentry_kunmap(dir, page); 297 set_page_dirty(page); 298 dir->i_mtime = dir->i_ctime = CURRENT_TIME; 299 mark_inode_dirty(dir); 300 301 f2fs_put_page(page, 1); 302 } 303 304 static void init_dent_inode(const struct qstr *name, struct page *ipage) 305 { 306 struct f2fs_inode *ri; 307 308 f2fs_wait_on_page_writeback(ipage, NODE); 309 310 /* copy name info. to this inode page */ 311 ri = F2FS_INODE(ipage); 312 ri->i_namelen = cpu_to_le32(name->len); 313 memcpy(ri->i_name, name->name, name->len); 314 set_page_dirty(ipage); 315 } 316 317 int update_dent_inode(struct inode *inode, struct inode *to, 318 const struct qstr *name) 319 { 320 struct page *page; 321 322 if (file_enc_name(to)) 323 return 0; 324 325 page = get_node_page(F2FS_I_SB(inode), inode->i_ino); 326 if (IS_ERR(page)) 327 return PTR_ERR(page); 328 329 init_dent_inode(name, page); 330 f2fs_put_page(page, 1); 331 332 return 0; 333 } 334 335 void do_make_empty_dir(struct inode *inode, struct inode *parent, 336 struct f2fs_dentry_ptr *d) 337 { 338 struct f2fs_dir_entry *de; 339 340 de = &d->dentry[0]; 341 de->name_len = cpu_to_le16(1); 342 de->hash_code = 0; 343 de->ino = cpu_to_le32(inode->i_ino); 344 memcpy(d->filename[0], ".", 1); 345 set_de_type(de, inode->i_mode); 346 347 de = &d->dentry[1]; 348 de->hash_code = 0; 349 de->name_len = cpu_to_le16(2); 350 de->ino = cpu_to_le32(parent->i_ino); 351 memcpy(d->filename[1], "..", 2); 352 set_de_type(de, parent->i_mode); 353 354 test_and_set_bit_le(0, (void *)d->bitmap); 355 test_and_set_bit_le(1, (void *)d->bitmap); 356 } 357 358 static int make_empty_dir(struct inode *inode, 359 struct inode *parent, struct page *page) 360 { 361 struct page *dentry_page; 362 struct f2fs_dentry_block *dentry_blk; 363 struct f2fs_dentry_ptr d; 364 365 if (f2fs_has_inline_dentry(inode)) 366 return make_empty_inline_dir(inode, parent, page); 367 368 dentry_page = get_new_data_page(inode, page, 0, true); 369 if (IS_ERR(dentry_page)) 370 return PTR_ERR(dentry_page); 371 372 dentry_blk = kmap_atomic(dentry_page); 373 374 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1); 375 do_make_empty_dir(inode, parent, &d); 376 377 kunmap_atomic(dentry_blk); 378 379 set_page_dirty(dentry_page); 380 f2fs_put_page(dentry_page, 1); 381 return 0; 382 } 383 384 struct page *init_inode_metadata(struct inode *inode, struct inode *dir, 385 const struct qstr *name, struct page *dpage) 386 { 387 struct page *page; 388 int err; 389 390 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) { 391 page = new_inode_page(inode); 392 if (IS_ERR(page)) 393 return page; 394 395 if (S_ISDIR(inode->i_mode)) { 396 err = make_empty_dir(inode, dir, page); 397 if (err) 398 goto error; 399 } 400 401 err = f2fs_init_acl(inode, dir, page, dpage); 402 if (err) 403 goto put_error; 404 405 err = f2fs_init_security(inode, dir, name, page); 406 if (err) 407 goto put_error; 408 409 if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) { 410 err = f2fs_inherit_context(dir, inode, page); 411 if (err) 412 goto put_error; 413 } 414 } else { 415 page = get_node_page(F2FS_I_SB(dir), inode->i_ino); 416 if (IS_ERR(page)) 417 return page; 418 419 set_cold_node(inode, page); 420 } 421 422 if (name) 423 init_dent_inode(name, page); 424 425 /* 426 * This file should be checkpointed during fsync. 427 * We lost i_pino from now on. 428 */ 429 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) { 430 file_lost_pino(inode); 431 /* 432 * If link the tmpfile to alias through linkat path, 433 * we should remove this inode from orphan list. 434 */ 435 if (inode->i_nlink == 0) 436 remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino); 437 inc_nlink(inode); 438 } 439 return page; 440 441 put_error: 442 f2fs_put_page(page, 1); 443 error: 444 /* once the failed inode becomes a bad inode, i_mode is S_IFREG */ 445 truncate_inode_pages(&inode->i_data, 0); 446 truncate_blocks(inode, 0, false); 447 remove_dirty_dir_inode(inode); 448 remove_inode_page(inode); 449 return ERR_PTR(err); 450 } 451 452 void update_parent_metadata(struct inode *dir, struct inode *inode, 453 unsigned int current_depth) 454 { 455 if (inode && is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) { 456 if (S_ISDIR(inode->i_mode)) { 457 inc_nlink(dir); 458 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 459 } 460 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE); 461 } 462 dir->i_mtime = dir->i_ctime = CURRENT_TIME; 463 mark_inode_dirty(dir); 464 465 if (F2FS_I(dir)->i_current_depth != current_depth) { 466 F2FS_I(dir)->i_current_depth = current_depth; 467 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 468 } 469 470 if (inode && is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) 471 clear_inode_flag(F2FS_I(inode), FI_INC_LINK); 472 } 473 474 int room_for_filename(const void *bitmap, int slots, int max_slots) 475 { 476 int bit_start = 0; 477 int zero_start, zero_end; 478 next: 479 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start); 480 if (zero_start >= max_slots) 481 return max_slots; 482 483 zero_end = find_next_bit_le(bitmap, max_slots, zero_start); 484 if (zero_end - zero_start >= slots) 485 return zero_start; 486 487 bit_start = zero_end + 1; 488 489 if (zero_end + 1 >= max_slots) 490 return max_slots; 491 goto next; 492 } 493 494 void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d, 495 const struct qstr *name, f2fs_hash_t name_hash, 496 unsigned int bit_pos) 497 { 498 struct f2fs_dir_entry *de; 499 int slots = GET_DENTRY_SLOTS(name->len); 500 int i; 501 502 de = &d->dentry[bit_pos]; 503 de->hash_code = name_hash; 504 de->name_len = cpu_to_le16(name->len); 505 memcpy(d->filename[bit_pos], name->name, name->len); 506 de->ino = cpu_to_le32(ino); 507 set_de_type(de, mode); 508 for (i = 0; i < slots; i++) 509 test_and_set_bit_le(bit_pos + i, (void *)d->bitmap); 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 f2fs_filename fname; 530 struct qstr new_name; 531 int slots, err; 532 533 err = f2fs_fname_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); 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 f2fs_fname_free_filename(&fname); 633 return err; 634 } 635 636 int f2fs_do_tmpfile(struct inode *inode, struct inode *dir) 637 { 638 struct page *page; 639 int err = 0; 640 641 down_write(&F2FS_I(inode)->i_sem); 642 page = init_inode_metadata(inode, dir, NULL, NULL); 643 if (IS_ERR(page)) { 644 err = PTR_ERR(page); 645 goto fail; 646 } 647 /* we don't need to mark_inode_dirty now */ 648 update_inode(inode, page); 649 f2fs_put_page(page, 1); 650 651 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE); 652 fail: 653 up_write(&F2FS_I(inode)->i_sem); 654 return err; 655 } 656 657 void f2fs_drop_nlink(struct inode *dir, struct inode *inode, struct page *page) 658 { 659 struct f2fs_sb_info *sbi = F2FS_I_SB(dir); 660 661 down_write(&F2FS_I(inode)->i_sem); 662 663 if (S_ISDIR(inode->i_mode)) { 664 drop_nlink(dir); 665 if (page) 666 update_inode(dir, page); 667 else 668 update_inode_page(dir); 669 } 670 inode->i_ctime = CURRENT_TIME; 671 672 drop_nlink(inode); 673 if (S_ISDIR(inode->i_mode)) { 674 drop_nlink(inode); 675 i_size_write(inode, 0); 676 } 677 up_write(&F2FS_I(inode)->i_sem); 678 update_inode_page(inode); 679 680 if (inode->i_nlink == 0) 681 add_orphan_inode(sbi, inode->i_ino); 682 else 683 release_orphan_inode(sbi); 684 } 685 686 /* 687 * It only removes the dentry from the dentry page, corresponding name 688 * entry in name page does not need to be touched during deletion. 689 */ 690 void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page, 691 struct inode *dir, struct inode *inode) 692 { 693 struct f2fs_dentry_block *dentry_blk; 694 unsigned int bit_pos; 695 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len)); 696 int i; 697 698 if (f2fs_has_inline_dentry(dir)) 699 return f2fs_delete_inline_entry(dentry, page, dir, inode); 700 701 lock_page(page); 702 f2fs_wait_on_page_writeback(page, DATA); 703 704 dentry_blk = page_address(page); 705 bit_pos = dentry - dentry_blk->dentry; 706 for (i = 0; i < slots; i++) 707 clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap); 708 709 /* Let's check and deallocate this dentry page */ 710 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap, 711 NR_DENTRY_IN_BLOCK, 712 0); 713 kunmap(page); /* kunmap - pair of f2fs_find_entry */ 714 set_page_dirty(page); 715 716 dir->i_ctime = dir->i_mtime = CURRENT_TIME; 717 718 if (inode) 719 f2fs_drop_nlink(dir, inode, NULL); 720 721 if (bit_pos == NR_DENTRY_IN_BLOCK) { 722 truncate_hole(dir, page->index, page->index + 1); 723 clear_page_dirty_for_io(page); 724 ClearPagePrivate(page); 725 ClearPageUptodate(page); 726 inode_dec_dirty_pages(dir); 727 } 728 f2fs_put_page(page, 1); 729 } 730 731 bool f2fs_empty_dir(struct inode *dir) 732 { 733 unsigned long bidx; 734 struct page *dentry_page; 735 unsigned int bit_pos; 736 struct f2fs_dentry_block *dentry_blk; 737 unsigned long nblock = dir_blocks(dir); 738 739 if (f2fs_has_inline_dentry(dir)) 740 return f2fs_empty_inline_dir(dir); 741 742 for (bidx = 0; bidx < nblock; bidx++) { 743 dentry_page = get_lock_data_page(dir, bidx); 744 if (IS_ERR(dentry_page)) { 745 if (PTR_ERR(dentry_page) == -ENOENT) 746 continue; 747 else 748 return false; 749 } 750 751 dentry_blk = kmap_atomic(dentry_page); 752 if (bidx == 0) 753 bit_pos = 2; 754 else 755 bit_pos = 0; 756 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap, 757 NR_DENTRY_IN_BLOCK, 758 bit_pos); 759 kunmap_atomic(dentry_blk); 760 761 f2fs_put_page(dentry_page, 1); 762 763 if (bit_pos < NR_DENTRY_IN_BLOCK) 764 return false; 765 } 766 return true; 767 } 768 769 bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, 770 unsigned int start_pos, struct f2fs_str *fstr) 771 { 772 unsigned char d_type = DT_UNKNOWN; 773 unsigned int bit_pos; 774 struct f2fs_dir_entry *de = NULL; 775 struct f2fs_str de_name = FSTR_INIT(NULL, 0); 776 777 bit_pos = ((unsigned long)ctx->pos % d->max); 778 779 while (bit_pos < d->max) { 780 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos); 781 if (bit_pos >= d->max) 782 break; 783 784 de = &d->dentry[bit_pos]; 785 if (de->file_type < F2FS_FT_MAX) 786 d_type = f2fs_filetype_table[de->file_type]; 787 else 788 d_type = DT_UNKNOWN; 789 790 /* encrypted case */ 791 de_name.name = d->filename[bit_pos]; 792 de_name.len = le16_to_cpu(de->name_len); 793 794 if (f2fs_encrypted_inode(d->inode)) { 795 int save_len = fstr->len; 796 int ret; 797 798 ret = f2fs_fname_disk_to_usr(d->inode, &de->hash_code, 799 &de_name, fstr); 800 de_name = *fstr; 801 fstr->len = save_len; 802 if (ret < 0) 803 return true; 804 } 805 806 if (!dir_emit(ctx, de_name.name, de_name.len, 807 le32_to_cpu(de->ino), d_type)) 808 return true; 809 810 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); 811 ctx->pos = start_pos + bit_pos; 812 } 813 return false; 814 } 815 816 static int f2fs_readdir(struct file *file, struct dir_context *ctx) 817 { 818 struct inode *inode = file_inode(file); 819 unsigned long npages = dir_blocks(inode); 820 struct f2fs_dentry_block *dentry_blk = NULL; 821 struct page *dentry_page = NULL; 822 struct file_ra_state *ra = &file->f_ra; 823 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK); 824 struct f2fs_dentry_ptr d; 825 struct f2fs_str fstr = FSTR_INIT(NULL, 0); 826 int err = 0; 827 828 if (f2fs_encrypted_inode(inode)) { 829 err = f2fs_get_encryption_info(inode); 830 if (err) 831 return err; 832 833 err = f2fs_fname_crypto_alloc_buffer(inode, F2FS_NAME_LEN, 834 &fstr); 835 if (err < 0) 836 return err; 837 } 838 839 if (f2fs_has_inline_dentry(inode)) { 840 err = f2fs_read_inline_dir(file, ctx, &fstr); 841 goto out; 842 } 843 844 /* readahead for multi pages of dir */ 845 if (npages - n > 1 && !ra_has_index(ra, n)) 846 page_cache_sync_readahead(inode->i_mapping, ra, file, n, 847 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES)); 848 849 for (; n < npages; n++) { 850 dentry_page = get_lock_data_page(inode, n); 851 if (IS_ERR(dentry_page)) 852 continue; 853 854 dentry_blk = kmap(dentry_page); 855 856 make_dentry_ptr(inode, &d, (void *)dentry_blk, 1); 857 858 if (f2fs_fill_dentries(ctx, &d, n * NR_DENTRY_IN_BLOCK, &fstr)) 859 goto stop; 860 861 ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK; 862 kunmap(dentry_page); 863 f2fs_put_page(dentry_page, 1); 864 dentry_page = NULL; 865 } 866 stop: 867 if (dentry_page && !IS_ERR(dentry_page)) { 868 kunmap(dentry_page); 869 f2fs_put_page(dentry_page, 1); 870 } 871 out: 872 f2fs_fname_crypto_free_buffer(&fstr); 873 return err; 874 } 875 876 const struct file_operations f2fs_dir_operations = { 877 .llseek = generic_file_llseek, 878 .read = generic_read_dir, 879 .iterate = f2fs_readdir, 880 .fsync = f2fs_sync_file, 881 .unlocked_ioctl = f2fs_ioctl, 882 #ifdef CONFIG_COMPAT 883 .compat_ioctl = f2fs_compat_ioctl, 884 #endif 885 }; 886