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 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 f2fs_filename fname; 222 int err; 223 224 *res_page = NULL; 225 226 err = f2fs_fname_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 f2fs_fname_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); 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); 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 f2fs_dir_entry *de; 345 346 de = &d->dentry[0]; 347 de->name_len = cpu_to_le16(1); 348 de->hash_code = 0; 349 de->ino = cpu_to_le32(inode->i_ino); 350 memcpy(d->filename[0], ".", 1); 351 set_de_type(de, inode->i_mode); 352 353 de = &d->dentry[1]; 354 de->hash_code = 0; 355 de->name_len = cpu_to_le16(2); 356 de->ino = cpu_to_le32(parent->i_ino); 357 memcpy(d->filename[1], "..", 2); 358 set_de_type(de, parent->i_mode); 359 360 test_and_set_bit_le(0, (void *)d->bitmap); 361 test_and_set_bit_le(1, (void *)d->bitmap); 362 } 363 364 static int make_empty_dir(struct inode *inode, 365 struct inode *parent, struct page *page) 366 { 367 struct page *dentry_page; 368 struct f2fs_dentry_block *dentry_blk; 369 struct f2fs_dentry_ptr d; 370 371 if (f2fs_has_inline_dentry(inode)) 372 return make_empty_inline_dir(inode, parent, page); 373 374 dentry_page = get_new_data_page(inode, page, 0, true); 375 if (IS_ERR(dentry_page)) 376 return PTR_ERR(dentry_page); 377 378 dentry_blk = kmap_atomic(dentry_page); 379 380 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1); 381 do_make_empty_dir(inode, parent, &d); 382 383 kunmap_atomic(dentry_blk); 384 385 set_page_dirty(dentry_page); 386 f2fs_put_page(dentry_page, 1); 387 return 0; 388 } 389 390 struct page *init_inode_metadata(struct inode *inode, struct inode *dir, 391 const struct qstr *name, struct page *dpage) 392 { 393 struct page *page; 394 int err; 395 396 if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) { 397 page = new_inode_page(inode); 398 if (IS_ERR(page)) 399 return page; 400 401 if (S_ISDIR(inode->i_mode)) { 402 err = make_empty_dir(inode, dir, page); 403 if (err) 404 goto error; 405 } 406 407 err = f2fs_init_acl(inode, dir, page, dpage); 408 if (err) 409 goto put_error; 410 411 err = f2fs_init_security(inode, dir, name, page); 412 if (err) 413 goto put_error; 414 415 if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) { 416 err = f2fs_inherit_context(dir, inode, page); 417 if (err) 418 goto put_error; 419 } 420 } else { 421 page = get_node_page(F2FS_I_SB(dir), inode->i_ino); 422 if (IS_ERR(page)) 423 return page; 424 425 set_cold_node(inode, page); 426 } 427 428 if (name) 429 init_dent_inode(name, page); 430 431 /* 432 * This file should be checkpointed during fsync. 433 * We lost i_pino from now on. 434 */ 435 if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) { 436 file_lost_pino(inode); 437 /* 438 * If link the tmpfile to alias through linkat path, 439 * we should remove this inode from orphan list. 440 */ 441 if (inode->i_nlink == 0) 442 remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino); 443 inc_nlink(inode); 444 } 445 return page; 446 447 put_error: 448 f2fs_put_page(page, 1); 449 error: 450 /* once the failed inode becomes a bad inode, i_mode is S_IFREG */ 451 truncate_inode_pages(&inode->i_data, 0); 452 truncate_blocks(inode, 0, false); 453 remove_dirty_inode(inode); 454 remove_inode_page(inode); 455 return ERR_PTR(err); 456 } 457 458 void update_parent_metadata(struct inode *dir, struct inode *inode, 459 unsigned int current_depth) 460 { 461 if (inode && is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) { 462 if (S_ISDIR(inode->i_mode)) { 463 inc_nlink(dir); 464 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 465 } 466 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE); 467 } 468 dir->i_mtime = dir->i_ctime = CURRENT_TIME; 469 mark_inode_dirty(dir); 470 471 if (F2FS_I(dir)->i_current_depth != current_depth) { 472 F2FS_I(dir)->i_current_depth = current_depth; 473 set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 474 } 475 476 if (inode && is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) 477 clear_inode_flag(F2FS_I(inode), FI_INC_LINK); 478 } 479 480 int room_for_filename(const void *bitmap, int slots, int max_slots) 481 { 482 int bit_start = 0; 483 int zero_start, zero_end; 484 next: 485 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start); 486 if (zero_start >= max_slots) 487 return max_slots; 488 489 zero_end = find_next_bit_le(bitmap, max_slots, zero_start); 490 if (zero_end - zero_start >= slots) 491 return zero_start; 492 493 bit_start = zero_end + 1; 494 495 if (zero_end + 1 >= max_slots) 496 return max_slots; 497 goto next; 498 } 499 500 void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d, 501 const struct qstr *name, f2fs_hash_t name_hash, 502 unsigned int bit_pos) 503 { 504 struct f2fs_dir_entry *de; 505 int slots = GET_DENTRY_SLOTS(name->len); 506 int i; 507 508 de = &d->dentry[bit_pos]; 509 de->hash_code = name_hash; 510 de->name_len = cpu_to_le16(name->len); 511 memcpy(d->filename[bit_pos], name->name, name->len); 512 de->ino = cpu_to_le32(ino); 513 set_de_type(de, mode); 514 for (i = 0; i < slots; i++) 515 test_and_set_bit_le(bit_pos + i, (void *)d->bitmap); 516 } 517 518 /* 519 * Caller should grab and release a rwsem by calling f2fs_lock_op() and 520 * f2fs_unlock_op(). 521 */ 522 int __f2fs_add_link(struct inode *dir, const struct qstr *name, 523 struct inode *inode, nid_t ino, umode_t mode) 524 { 525 unsigned int bit_pos; 526 unsigned int level; 527 unsigned int current_depth; 528 unsigned long bidx, block; 529 f2fs_hash_t dentry_hash; 530 unsigned int nbucket, nblock; 531 struct page *dentry_page = NULL; 532 struct f2fs_dentry_block *dentry_blk = NULL; 533 struct f2fs_dentry_ptr d; 534 struct page *page = NULL; 535 struct f2fs_filename fname; 536 struct qstr new_name; 537 int slots, err; 538 539 err = f2fs_fname_setup_filename(dir, name, 0, &fname); 540 if (err) 541 return err; 542 543 new_name.name = fname_name(&fname); 544 new_name.len = fname_len(&fname); 545 546 if (f2fs_has_inline_dentry(dir)) { 547 err = f2fs_add_inline_entry(dir, &new_name, inode, ino, mode); 548 if (!err || err != -EAGAIN) 549 goto out; 550 else 551 err = 0; 552 } 553 554 level = 0; 555 slots = GET_DENTRY_SLOTS(new_name.len); 556 dentry_hash = f2fs_dentry_hash(&new_name); 557 558 current_depth = F2FS_I(dir)->i_current_depth; 559 if (F2FS_I(dir)->chash == dentry_hash) { 560 level = F2FS_I(dir)->clevel; 561 F2FS_I(dir)->chash = 0; 562 } 563 564 start: 565 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH)) { 566 err = -ENOSPC; 567 goto out; 568 } 569 570 /* Increase the depth, if required */ 571 if (level == current_depth) 572 ++current_depth; 573 574 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level); 575 nblock = bucket_blocks(level); 576 577 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level, 578 (le32_to_cpu(dentry_hash) % nbucket)); 579 580 for (block = bidx; block <= (bidx + nblock - 1); block++) { 581 dentry_page = get_new_data_page(dir, NULL, block, true); 582 if (IS_ERR(dentry_page)) { 583 err = PTR_ERR(dentry_page); 584 goto out; 585 } 586 587 dentry_blk = kmap(dentry_page); 588 bit_pos = room_for_filename(&dentry_blk->dentry_bitmap, 589 slots, NR_DENTRY_IN_BLOCK); 590 if (bit_pos < NR_DENTRY_IN_BLOCK) 591 goto add_dentry; 592 593 kunmap(dentry_page); 594 f2fs_put_page(dentry_page, 1); 595 } 596 597 /* Move to next level to find the empty slot for new dentry */ 598 ++level; 599 goto start; 600 add_dentry: 601 f2fs_wait_on_page_writeback(dentry_page, DATA); 602 603 if (inode) { 604 down_write(&F2FS_I(inode)->i_sem); 605 page = init_inode_metadata(inode, dir, &new_name, NULL); 606 if (IS_ERR(page)) { 607 err = PTR_ERR(page); 608 goto fail; 609 } 610 if (f2fs_encrypted_inode(dir)) 611 file_set_enc_name(inode); 612 } 613 614 make_dentry_ptr(NULL, &d, (void *)dentry_blk, 1); 615 f2fs_update_dentry(ino, mode, &d, &new_name, dentry_hash, bit_pos); 616 617 set_page_dirty(dentry_page); 618 619 if (inode) { 620 /* we don't need to mark_inode_dirty now */ 621 F2FS_I(inode)->i_pino = dir->i_ino; 622 update_inode(inode, page); 623 f2fs_put_page(page, 1); 624 } 625 626 update_parent_metadata(dir, inode, current_depth); 627 fail: 628 if (inode) 629 up_write(&F2FS_I(inode)->i_sem); 630 631 if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR)) { 632 update_inode_page(dir); 633 clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR); 634 } 635 kunmap(dentry_page); 636 f2fs_put_page(dentry_page, 1); 637 out: 638 f2fs_fname_free_filename(&fname); 639 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME); 640 return err; 641 } 642 643 int f2fs_do_tmpfile(struct inode *inode, struct inode *dir) 644 { 645 struct page *page; 646 int err = 0; 647 648 down_write(&F2FS_I(inode)->i_sem); 649 page = init_inode_metadata(inode, dir, NULL, NULL); 650 if (IS_ERR(page)) { 651 err = PTR_ERR(page); 652 goto fail; 653 } 654 /* we don't need to mark_inode_dirty now */ 655 update_inode(inode, page); 656 f2fs_put_page(page, 1); 657 658 clear_inode_flag(F2FS_I(inode), FI_NEW_INODE); 659 fail: 660 up_write(&F2FS_I(inode)->i_sem); 661 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME); 662 return err; 663 } 664 665 void f2fs_drop_nlink(struct inode *dir, struct inode *inode, struct page *page) 666 { 667 struct f2fs_sb_info *sbi = F2FS_I_SB(dir); 668 669 down_write(&F2FS_I(inode)->i_sem); 670 671 if (S_ISDIR(inode->i_mode)) { 672 drop_nlink(dir); 673 if (page) 674 update_inode(dir, page); 675 else 676 update_inode_page(dir); 677 } 678 inode->i_ctime = CURRENT_TIME; 679 680 drop_nlink(inode); 681 if (S_ISDIR(inode->i_mode)) { 682 drop_nlink(inode); 683 i_size_write(inode, 0); 684 } 685 up_write(&F2FS_I(inode)->i_sem); 686 update_inode_page(inode); 687 688 if (inode->i_nlink == 0) 689 add_orphan_inode(sbi, inode->i_ino); 690 else 691 release_orphan_inode(sbi); 692 } 693 694 /* 695 * It only removes the dentry from the dentry page, corresponding name 696 * entry in name page does not need to be touched during deletion. 697 */ 698 void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page, 699 struct inode *dir, struct inode *inode) 700 { 701 struct f2fs_dentry_block *dentry_blk; 702 unsigned int bit_pos; 703 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len)); 704 int i; 705 706 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME); 707 708 if (f2fs_has_inline_dentry(dir)) 709 return f2fs_delete_inline_entry(dentry, page, dir, inode); 710 711 lock_page(page); 712 f2fs_wait_on_page_writeback(page, DATA); 713 714 dentry_blk = page_address(page); 715 bit_pos = dentry - dentry_blk->dentry; 716 for (i = 0; i < slots; i++) 717 clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap); 718 719 /* Let's check and deallocate this dentry page */ 720 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap, 721 NR_DENTRY_IN_BLOCK, 722 0); 723 kunmap(page); /* kunmap - pair of f2fs_find_entry */ 724 set_page_dirty(page); 725 726 dir->i_ctime = dir->i_mtime = CURRENT_TIME; 727 728 if (inode) 729 f2fs_drop_nlink(dir, inode, NULL); 730 731 if (bit_pos == NR_DENTRY_IN_BLOCK && 732 !truncate_hole(dir, page->index, page->index + 1)) { 733 clear_page_dirty_for_io(page); 734 ClearPagePrivate(page); 735 ClearPageUptodate(page); 736 inode_dec_dirty_pages(dir); 737 } 738 f2fs_put_page(page, 1); 739 } 740 741 bool f2fs_empty_dir(struct inode *dir) 742 { 743 unsigned long bidx; 744 struct page *dentry_page; 745 unsigned int bit_pos; 746 struct f2fs_dentry_block *dentry_blk; 747 unsigned long nblock = dir_blocks(dir); 748 749 if (f2fs_has_inline_dentry(dir)) 750 return f2fs_empty_inline_dir(dir); 751 752 for (bidx = 0; bidx < nblock; bidx++) { 753 dentry_page = get_lock_data_page(dir, bidx, false); 754 if (IS_ERR(dentry_page)) { 755 if (PTR_ERR(dentry_page) == -ENOENT) 756 continue; 757 else 758 return false; 759 } 760 761 dentry_blk = kmap_atomic(dentry_page); 762 if (bidx == 0) 763 bit_pos = 2; 764 else 765 bit_pos = 0; 766 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap, 767 NR_DENTRY_IN_BLOCK, 768 bit_pos); 769 kunmap_atomic(dentry_blk); 770 771 f2fs_put_page(dentry_page, 1); 772 773 if (bit_pos < NR_DENTRY_IN_BLOCK) 774 return false; 775 } 776 return true; 777 } 778 779 bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, 780 unsigned int start_pos, struct f2fs_str *fstr) 781 { 782 unsigned char d_type = DT_UNKNOWN; 783 unsigned int bit_pos; 784 struct f2fs_dir_entry *de = NULL; 785 struct f2fs_str de_name = FSTR_INIT(NULL, 0); 786 787 bit_pos = ((unsigned long)ctx->pos % d->max); 788 789 while (bit_pos < d->max) { 790 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos); 791 if (bit_pos >= d->max) 792 break; 793 794 de = &d->dentry[bit_pos]; 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 = f2fs_fname_disk_to_usr(d->inode, &de->hash_code, 814 &de_name, fstr); 815 kfree(de_name.name); 816 if (ret < 0) 817 return true; 818 819 de_name = *fstr; 820 fstr->len = save_len; 821 } 822 823 if (!dir_emit(ctx, de_name.name, de_name.len, 824 le32_to_cpu(de->ino), d_type)) 825 return true; 826 827 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); 828 ctx->pos = start_pos + bit_pos; 829 } 830 return false; 831 } 832 833 static int f2fs_readdir(struct file *file, struct dir_context *ctx) 834 { 835 struct inode *inode = file_inode(file); 836 unsigned long npages = dir_blocks(inode); 837 struct f2fs_dentry_block *dentry_blk = NULL; 838 struct page *dentry_page = NULL; 839 struct file_ra_state *ra = &file->f_ra; 840 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK); 841 struct f2fs_dentry_ptr d; 842 struct f2fs_str fstr = FSTR_INIT(NULL, 0); 843 int err = 0; 844 845 if (f2fs_encrypted_inode(inode)) { 846 err = f2fs_get_encryption_info(inode); 847 if (err) 848 return err; 849 850 err = f2fs_fname_crypto_alloc_buffer(inode, F2FS_NAME_LEN, 851 &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 f2fs_fname_crypto_free_buffer(&fstr); 892 return err; 893 } 894 895 const struct file_operations f2fs_dir_operations = { 896 .llseek = generic_file_llseek, 897 .read = generic_read_dir, 898 .iterate = f2fs_readdir, 899 .fsync = f2fs_sync_file, 900 .unlocked_ioctl = f2fs_ioctl, 901 #ifdef CONFIG_COMPAT 902 .compat_ioctl = f2fs_compat_ioctl, 903 #endif 904 }; 905