1 /* 2 * linux/fs/ext4/namei.c 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 * 9 * from 10 * 11 * linux/fs/minix/namei.c 12 * 13 * Copyright (C) 1991, 1992 Linus Torvalds 14 * 15 * Big-endian to little-endian byte-swapping/bitmaps by 16 * David S. Miller (davem@caip.rutgers.edu), 1995 17 * Directory entry file type support and forward compatibility hooks 18 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998 19 * Hash Tree Directory indexing (c) 20 * Daniel Phillips, 2001 21 * Hash Tree Directory indexing porting 22 * Christopher Li, 2002 23 * Hash Tree Directory indexing cleanup 24 * Theodore Ts'o, 2002 25 */ 26 27 #include <linux/fs.h> 28 #include <linux/pagemap.h> 29 #include <linux/time.h> 30 #include <linux/fcntl.h> 31 #include <linux/stat.h> 32 #include <linux/string.h> 33 #include <linux/quotaops.h> 34 #include <linux/buffer_head.h> 35 #include <linux/bio.h> 36 #include "ext4.h" 37 #include "ext4_jbd2.h" 38 39 #include "xattr.h" 40 #include "acl.h" 41 42 #include <trace/events/ext4.h> 43 /* 44 * define how far ahead to read directories while searching them. 45 */ 46 #define NAMEI_RA_CHUNKS 2 47 #define NAMEI_RA_BLOCKS 4 48 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) 49 50 static struct buffer_head *ext4_append(handle_t *handle, 51 struct inode *inode, 52 ext4_lblk_t *block) 53 { 54 struct buffer_head *bh; 55 int err; 56 57 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb && 58 ((inode->i_size >> 10) >= 59 EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) 60 return ERR_PTR(-ENOSPC); 61 62 *block = inode->i_size >> inode->i_sb->s_blocksize_bits; 63 64 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE); 65 if (IS_ERR(bh)) 66 return bh; 67 inode->i_size += inode->i_sb->s_blocksize; 68 EXT4_I(inode)->i_disksize = inode->i_size; 69 BUFFER_TRACE(bh, "get_write_access"); 70 err = ext4_journal_get_write_access(handle, bh); 71 if (err) { 72 brelse(bh); 73 ext4_std_error(inode->i_sb, err); 74 return ERR_PTR(err); 75 } 76 return bh; 77 } 78 79 static int ext4_dx_csum_verify(struct inode *inode, 80 struct ext4_dir_entry *dirent); 81 82 typedef enum { 83 EITHER, INDEX, DIRENT 84 } dirblock_type_t; 85 86 #define ext4_read_dirblock(inode, block, type) \ 87 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__) 88 89 static struct buffer_head *__ext4_read_dirblock(struct inode *inode, 90 ext4_lblk_t block, 91 dirblock_type_t type, 92 const char *func, 93 unsigned int line) 94 { 95 struct buffer_head *bh; 96 struct ext4_dir_entry *dirent; 97 int is_dx_block = 0; 98 99 bh = ext4_bread(NULL, inode, block, 0); 100 if (IS_ERR(bh)) { 101 __ext4_warning(inode->i_sb, func, line, 102 "inode #%lu: lblock %lu: comm %s: " 103 "error %ld reading directory block", 104 inode->i_ino, (unsigned long)block, 105 current->comm, PTR_ERR(bh)); 106 107 return bh; 108 } 109 if (!bh) { 110 ext4_error_inode(inode, func, line, block, 111 "Directory hole found"); 112 return ERR_PTR(-EFSCORRUPTED); 113 } 114 dirent = (struct ext4_dir_entry *) bh->b_data; 115 /* Determine whether or not we have an index block */ 116 if (is_dx(inode)) { 117 if (block == 0) 118 is_dx_block = 1; 119 else if (ext4_rec_len_from_disk(dirent->rec_len, 120 inode->i_sb->s_blocksize) == 121 inode->i_sb->s_blocksize) 122 is_dx_block = 1; 123 } 124 if (!is_dx_block && type == INDEX) { 125 ext4_error_inode(inode, func, line, block, 126 "directory leaf block found instead of index block"); 127 return ERR_PTR(-EFSCORRUPTED); 128 } 129 if (!ext4_has_metadata_csum(inode->i_sb) || 130 buffer_verified(bh)) 131 return bh; 132 133 /* 134 * An empty leaf block can get mistaken for a index block; for 135 * this reason, we can only check the index checksum when the 136 * caller is sure it should be an index block. 137 */ 138 if (is_dx_block && type == INDEX) { 139 if (ext4_dx_csum_verify(inode, dirent)) 140 set_buffer_verified(bh); 141 else { 142 ext4_error_inode(inode, func, line, block, 143 "Directory index failed checksum"); 144 brelse(bh); 145 return ERR_PTR(-EFSBADCRC); 146 } 147 } 148 if (!is_dx_block) { 149 if (ext4_dirent_csum_verify(inode, dirent)) 150 set_buffer_verified(bh); 151 else { 152 ext4_error_inode(inode, func, line, block, 153 "Directory block failed checksum"); 154 brelse(bh); 155 return ERR_PTR(-EFSBADCRC); 156 } 157 } 158 return bh; 159 } 160 161 #ifndef assert 162 #define assert(test) J_ASSERT(test) 163 #endif 164 165 #ifdef DX_DEBUG 166 #define dxtrace(command) command 167 #else 168 #define dxtrace(command) 169 #endif 170 171 struct fake_dirent 172 { 173 __le32 inode; 174 __le16 rec_len; 175 u8 name_len; 176 u8 file_type; 177 }; 178 179 struct dx_countlimit 180 { 181 __le16 limit; 182 __le16 count; 183 }; 184 185 struct dx_entry 186 { 187 __le32 hash; 188 __le32 block; 189 }; 190 191 /* 192 * dx_root_info is laid out so that if it should somehow get overlaid by a 193 * dirent the two low bits of the hash version will be zero. Therefore, the 194 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 195 */ 196 197 struct dx_root 198 { 199 struct fake_dirent dot; 200 char dot_name[4]; 201 struct fake_dirent dotdot; 202 char dotdot_name[4]; 203 struct dx_root_info 204 { 205 __le32 reserved_zero; 206 u8 hash_version; 207 u8 info_length; /* 8 */ 208 u8 indirect_levels; 209 u8 unused_flags; 210 } 211 info; 212 struct dx_entry entries[0]; 213 }; 214 215 struct dx_node 216 { 217 struct fake_dirent fake; 218 struct dx_entry entries[0]; 219 }; 220 221 222 struct dx_frame 223 { 224 struct buffer_head *bh; 225 struct dx_entry *entries; 226 struct dx_entry *at; 227 }; 228 229 struct dx_map_entry 230 { 231 u32 hash; 232 u16 offs; 233 u16 size; 234 }; 235 236 /* 237 * This goes at the end of each htree block. 238 */ 239 struct dx_tail { 240 u32 dt_reserved; 241 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */ 242 }; 243 244 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry); 245 static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value); 246 static inline unsigned dx_get_hash(struct dx_entry *entry); 247 static void dx_set_hash(struct dx_entry *entry, unsigned value); 248 static unsigned dx_get_count(struct dx_entry *entries); 249 static unsigned dx_get_limit(struct dx_entry *entries); 250 static void dx_set_count(struct dx_entry *entries, unsigned value); 251 static void dx_set_limit(struct dx_entry *entries, unsigned value); 252 static unsigned dx_root_limit(struct inode *dir, unsigned infosize); 253 static unsigned dx_node_limit(struct inode *dir); 254 static struct dx_frame *dx_probe(struct ext4_filename *fname, 255 struct inode *dir, 256 struct dx_hash_info *hinfo, 257 struct dx_frame *frame); 258 static void dx_release(struct dx_frame *frames); 259 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 260 unsigned blocksize, struct dx_hash_info *hinfo, 261 struct dx_map_entry map[]); 262 static void dx_sort_map(struct dx_map_entry *map, unsigned count); 263 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to, 264 struct dx_map_entry *offsets, int count, unsigned blocksize); 265 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize); 266 static void dx_insert_block(struct dx_frame *frame, 267 u32 hash, ext4_lblk_t block); 268 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 269 struct dx_frame *frame, 270 struct dx_frame *frames, 271 __u32 *start_hash); 272 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 273 struct ext4_filename *fname, 274 struct ext4_dir_entry_2 **res_dir); 275 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 276 struct inode *dir, struct inode *inode); 277 278 /* checksumming functions */ 279 void initialize_dirent_tail(struct ext4_dir_entry_tail *t, 280 unsigned int blocksize) 281 { 282 memset(t, 0, sizeof(struct ext4_dir_entry_tail)); 283 t->det_rec_len = ext4_rec_len_to_disk( 284 sizeof(struct ext4_dir_entry_tail), blocksize); 285 t->det_reserved_ft = EXT4_FT_DIR_CSUM; 286 } 287 288 /* Walk through a dirent block to find a checksum "dirent" at the tail */ 289 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode, 290 struct ext4_dir_entry *de) 291 { 292 struct ext4_dir_entry_tail *t; 293 294 #ifdef PARANOID 295 struct ext4_dir_entry *d, *top; 296 297 d = de; 298 top = (struct ext4_dir_entry *)(((void *)de) + 299 (EXT4_BLOCK_SIZE(inode->i_sb) - 300 sizeof(struct ext4_dir_entry_tail))); 301 while (d < top && d->rec_len) 302 d = (struct ext4_dir_entry *)(((void *)d) + 303 le16_to_cpu(d->rec_len)); 304 305 if (d != top) 306 return NULL; 307 308 t = (struct ext4_dir_entry_tail *)d; 309 #else 310 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb)); 311 #endif 312 313 if (t->det_reserved_zero1 || 314 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) || 315 t->det_reserved_zero2 || 316 t->det_reserved_ft != EXT4_FT_DIR_CSUM) 317 return NULL; 318 319 return t; 320 } 321 322 static __le32 ext4_dirent_csum(struct inode *inode, 323 struct ext4_dir_entry *dirent, int size) 324 { 325 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 326 struct ext4_inode_info *ei = EXT4_I(inode); 327 __u32 csum; 328 329 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 330 return cpu_to_le32(csum); 331 } 332 333 #define warn_no_space_for_csum(inode) \ 334 __warn_no_space_for_csum((inode), __func__, __LINE__) 335 336 static void __warn_no_space_for_csum(struct inode *inode, const char *func, 337 unsigned int line) 338 { 339 __ext4_warning_inode(inode, func, line, 340 "No space for directory leaf checksum. Please run e2fsck -D."); 341 } 342 343 int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent) 344 { 345 struct ext4_dir_entry_tail *t; 346 347 if (!ext4_has_metadata_csum(inode->i_sb)) 348 return 1; 349 350 t = get_dirent_tail(inode, dirent); 351 if (!t) { 352 warn_no_space_for_csum(inode); 353 return 0; 354 } 355 356 if (t->det_checksum != ext4_dirent_csum(inode, dirent, 357 (void *)t - (void *)dirent)) 358 return 0; 359 360 return 1; 361 } 362 363 static void ext4_dirent_csum_set(struct inode *inode, 364 struct ext4_dir_entry *dirent) 365 { 366 struct ext4_dir_entry_tail *t; 367 368 if (!ext4_has_metadata_csum(inode->i_sb)) 369 return; 370 371 t = get_dirent_tail(inode, dirent); 372 if (!t) { 373 warn_no_space_for_csum(inode); 374 return; 375 } 376 377 t->det_checksum = ext4_dirent_csum(inode, dirent, 378 (void *)t - (void *)dirent); 379 } 380 381 int ext4_handle_dirty_dirent_node(handle_t *handle, 382 struct inode *inode, 383 struct buffer_head *bh) 384 { 385 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 386 return ext4_handle_dirty_metadata(handle, inode, bh); 387 } 388 389 static struct dx_countlimit *get_dx_countlimit(struct inode *inode, 390 struct ext4_dir_entry *dirent, 391 int *offset) 392 { 393 struct ext4_dir_entry *dp; 394 struct dx_root_info *root; 395 int count_offset; 396 397 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb)) 398 count_offset = 8; 399 else if (le16_to_cpu(dirent->rec_len) == 12) { 400 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12); 401 if (le16_to_cpu(dp->rec_len) != 402 EXT4_BLOCK_SIZE(inode->i_sb) - 12) 403 return NULL; 404 root = (struct dx_root_info *)(((void *)dp + 12)); 405 if (root->reserved_zero || 406 root->info_length != sizeof(struct dx_root_info)) 407 return NULL; 408 count_offset = 32; 409 } else 410 return NULL; 411 412 if (offset) 413 *offset = count_offset; 414 return (struct dx_countlimit *)(((void *)dirent) + count_offset); 415 } 416 417 static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent, 418 int count_offset, int count, struct dx_tail *t) 419 { 420 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 421 struct ext4_inode_info *ei = EXT4_I(inode); 422 __u32 csum; 423 int size; 424 __u32 dummy_csum = 0; 425 int offset = offsetof(struct dx_tail, dt_checksum); 426 427 size = count_offset + (count * sizeof(struct dx_entry)); 428 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 429 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset); 430 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); 431 432 return cpu_to_le32(csum); 433 } 434 435 static int ext4_dx_csum_verify(struct inode *inode, 436 struct ext4_dir_entry *dirent) 437 { 438 struct dx_countlimit *c; 439 struct dx_tail *t; 440 int count_offset, limit, count; 441 442 if (!ext4_has_metadata_csum(inode->i_sb)) 443 return 1; 444 445 c = get_dx_countlimit(inode, dirent, &count_offset); 446 if (!c) { 447 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 448 return 0; 449 } 450 limit = le16_to_cpu(c->limit); 451 count = le16_to_cpu(c->count); 452 if (count_offset + (limit * sizeof(struct dx_entry)) > 453 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 454 warn_no_space_for_csum(inode); 455 return 0; 456 } 457 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 458 459 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset, 460 count, t)) 461 return 0; 462 return 1; 463 } 464 465 static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent) 466 { 467 struct dx_countlimit *c; 468 struct dx_tail *t; 469 int count_offset, limit, count; 470 471 if (!ext4_has_metadata_csum(inode->i_sb)) 472 return; 473 474 c = get_dx_countlimit(inode, dirent, &count_offset); 475 if (!c) { 476 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 477 return; 478 } 479 limit = le16_to_cpu(c->limit); 480 count = le16_to_cpu(c->count); 481 if (count_offset + (limit * sizeof(struct dx_entry)) > 482 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 483 warn_no_space_for_csum(inode); 484 return; 485 } 486 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 487 488 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t); 489 } 490 491 static inline int ext4_handle_dirty_dx_node(handle_t *handle, 492 struct inode *inode, 493 struct buffer_head *bh) 494 { 495 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 496 return ext4_handle_dirty_metadata(handle, inode, bh); 497 } 498 499 /* 500 * p is at least 6 bytes before the end of page 501 */ 502 static inline struct ext4_dir_entry_2 * 503 ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize) 504 { 505 return (struct ext4_dir_entry_2 *)((char *)p + 506 ext4_rec_len_from_disk(p->rec_len, blocksize)); 507 } 508 509 /* 510 * Future: use high four bits of block for coalesce-on-delete flags 511 * Mask them off for now. 512 */ 513 514 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry) 515 { 516 return le32_to_cpu(entry->block) & 0x0fffffff; 517 } 518 519 static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value) 520 { 521 entry->block = cpu_to_le32(value); 522 } 523 524 static inline unsigned dx_get_hash(struct dx_entry *entry) 525 { 526 return le32_to_cpu(entry->hash); 527 } 528 529 static inline void dx_set_hash(struct dx_entry *entry, unsigned value) 530 { 531 entry->hash = cpu_to_le32(value); 532 } 533 534 static inline unsigned dx_get_count(struct dx_entry *entries) 535 { 536 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 537 } 538 539 static inline unsigned dx_get_limit(struct dx_entry *entries) 540 { 541 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 542 } 543 544 static inline void dx_set_count(struct dx_entry *entries, unsigned value) 545 { 546 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 547 } 548 549 static inline void dx_set_limit(struct dx_entry *entries, unsigned value) 550 { 551 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 552 } 553 554 static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize) 555 { 556 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) - 557 EXT4_DIR_REC_LEN(2) - infosize; 558 559 if (ext4_has_metadata_csum(dir->i_sb)) 560 entry_space -= sizeof(struct dx_tail); 561 return entry_space / sizeof(struct dx_entry); 562 } 563 564 static inline unsigned dx_node_limit(struct inode *dir) 565 { 566 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0); 567 568 if (ext4_has_metadata_csum(dir->i_sb)) 569 entry_space -= sizeof(struct dx_tail); 570 return entry_space / sizeof(struct dx_entry); 571 } 572 573 /* 574 * Debug 575 */ 576 #ifdef DX_DEBUG 577 static void dx_show_index(char * label, struct dx_entry *entries) 578 { 579 int i, n = dx_get_count (entries); 580 printk(KERN_DEBUG "%s index", label); 581 for (i = 0; i < n; i++) { 582 printk(KERN_CONT " %x->%lu", 583 i ? dx_get_hash(entries + i) : 0, 584 (unsigned long)dx_get_block(entries + i)); 585 } 586 printk(KERN_CONT "\n"); 587 } 588 589 struct stats 590 { 591 unsigned names; 592 unsigned space; 593 unsigned bcount; 594 }; 595 596 static struct stats dx_show_leaf(struct inode *dir, 597 struct dx_hash_info *hinfo, 598 struct ext4_dir_entry_2 *de, 599 int size, int show_names) 600 { 601 unsigned names = 0, space = 0; 602 char *base = (char *) de; 603 struct dx_hash_info h = *hinfo; 604 605 printk("names: "); 606 while ((char *) de < base + size) 607 { 608 if (de->inode) 609 { 610 if (show_names) 611 { 612 #ifdef CONFIG_EXT4_FS_ENCRYPTION 613 int len; 614 char *name; 615 struct fscrypt_str fname_crypto_str = 616 FSTR_INIT(NULL, 0); 617 int res = 0; 618 619 name = de->name; 620 len = de->name_len; 621 if (ext4_encrypted_inode(dir)) 622 res = fscrypt_get_encryption_info(dir); 623 if (res) { 624 printk(KERN_WARNING "Error setting up" 625 " fname crypto: %d\n", res); 626 } 627 if (!fscrypt_has_encryption_key(dir)) { 628 /* Directory is not encrypted */ 629 ext4fs_dirhash(de->name, 630 de->name_len, &h); 631 printk("%*.s:(U)%x.%u ", len, 632 name, h.hash, 633 (unsigned) ((char *) de 634 - base)); 635 } else { 636 struct fscrypt_str de_name = 637 FSTR_INIT(name, len); 638 639 /* Directory is encrypted */ 640 res = fscrypt_fname_alloc_buffer( 641 dir, len, 642 &fname_crypto_str); 643 if (res) 644 printk(KERN_WARNING "Error " 645 "allocating crypto " 646 "buffer--skipping " 647 "crypto\n"); 648 res = fscrypt_fname_disk_to_usr(dir, 649 0, 0, &de_name, 650 &fname_crypto_str); 651 if (res) { 652 printk(KERN_WARNING "Error " 653 "converting filename " 654 "from disk to usr" 655 "\n"); 656 name = "??"; 657 len = 2; 658 } else { 659 name = fname_crypto_str.name; 660 len = fname_crypto_str.len; 661 } 662 ext4fs_dirhash(de->name, de->name_len, 663 &h); 664 printk("%*.s:(E)%x.%u ", len, name, 665 h.hash, (unsigned) ((char *) de 666 - base)); 667 fscrypt_fname_free_buffer( 668 &fname_crypto_str); 669 } 670 #else 671 int len = de->name_len; 672 char *name = de->name; 673 ext4fs_dirhash(de->name, de->name_len, &h); 674 printk("%*.s:%x.%u ", len, name, h.hash, 675 (unsigned) ((char *) de - base)); 676 #endif 677 } 678 space += EXT4_DIR_REC_LEN(de->name_len); 679 names++; 680 } 681 de = ext4_next_entry(de, size); 682 } 683 printk(KERN_CONT "(%i)\n", names); 684 return (struct stats) { names, space, 1 }; 685 } 686 687 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 688 struct dx_entry *entries, int levels) 689 { 690 unsigned blocksize = dir->i_sb->s_blocksize; 691 unsigned count = dx_get_count(entries), names = 0, space = 0, i; 692 unsigned bcount = 0; 693 struct buffer_head *bh; 694 printk("%i indexed blocks...\n", count); 695 for (i = 0; i < count; i++, entries++) 696 { 697 ext4_lblk_t block = dx_get_block(entries); 698 ext4_lblk_t hash = i ? dx_get_hash(entries): 0; 699 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 700 struct stats stats; 701 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 702 bh = ext4_bread(NULL,dir, block, 0); 703 if (!bh || IS_ERR(bh)) 704 continue; 705 stats = levels? 706 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 707 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) 708 bh->b_data, blocksize, 0); 709 names += stats.names; 710 space += stats.space; 711 bcount += stats.bcount; 712 brelse(bh); 713 } 714 if (bcount) 715 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n", 716 levels ? "" : " ", names, space/bcount, 717 (space/bcount)*100/blocksize); 718 return (struct stats) { names, space, bcount}; 719 } 720 #endif /* DX_DEBUG */ 721 722 /* 723 * Probe for a directory leaf block to search. 724 * 725 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 726 * error in the directory index, and the caller should fall back to 727 * searching the directory normally. The callers of dx_probe **MUST** 728 * check for this error code, and make sure it never gets reflected 729 * back to userspace. 730 */ 731 static struct dx_frame * 732 dx_probe(struct ext4_filename *fname, struct inode *dir, 733 struct dx_hash_info *hinfo, struct dx_frame *frame_in) 734 { 735 unsigned count, indirect; 736 struct dx_entry *at, *entries, *p, *q, *m; 737 struct dx_root *root; 738 struct dx_frame *frame = frame_in; 739 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR); 740 u32 hash; 741 742 memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0])); 743 frame->bh = ext4_read_dirblock(dir, 0, INDEX); 744 if (IS_ERR(frame->bh)) 745 return (struct dx_frame *) frame->bh; 746 747 root = (struct dx_root *) frame->bh->b_data; 748 if (root->info.hash_version != DX_HASH_TEA && 749 root->info.hash_version != DX_HASH_HALF_MD4 && 750 root->info.hash_version != DX_HASH_LEGACY) { 751 ext4_warning_inode(dir, "Unrecognised inode hash code %u", 752 root->info.hash_version); 753 goto fail; 754 } 755 if (fname) 756 hinfo = &fname->hinfo; 757 hinfo->hash_version = root->info.hash_version; 758 if (hinfo->hash_version <= DX_HASH_TEA) 759 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 760 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; 761 if (fname && fname_name(fname)) 762 ext4fs_dirhash(fname_name(fname), fname_len(fname), hinfo); 763 hash = hinfo->hash; 764 765 if (root->info.unused_flags & 1) { 766 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x", 767 root->info.unused_flags); 768 goto fail; 769 } 770 771 indirect = root->info.indirect_levels; 772 if (indirect >= ext4_dir_htree_level(dir->i_sb)) { 773 ext4_warning(dir->i_sb, 774 "Directory (ino: %lu) htree depth %#06x exceed" 775 "supported value", dir->i_ino, 776 ext4_dir_htree_level(dir->i_sb)); 777 if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) { 778 ext4_warning(dir->i_sb, "Enable large directory " 779 "feature to access it"); 780 } 781 goto fail; 782 } 783 784 entries = (struct dx_entry *)(((char *)&root->info) + 785 root->info.info_length); 786 787 if (dx_get_limit(entries) != dx_root_limit(dir, 788 root->info.info_length)) { 789 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u", 790 dx_get_limit(entries), 791 dx_root_limit(dir, root->info.info_length)); 792 goto fail; 793 } 794 795 dxtrace(printk("Look up %x", hash)); 796 while (1) { 797 count = dx_get_count(entries); 798 if (!count || count > dx_get_limit(entries)) { 799 ext4_warning_inode(dir, 800 "dx entry: count %u beyond limit %u", 801 count, dx_get_limit(entries)); 802 goto fail; 803 } 804 805 p = entries + 1; 806 q = entries + count - 1; 807 while (p <= q) { 808 m = p + (q - p) / 2; 809 dxtrace(printk(KERN_CONT ".")); 810 if (dx_get_hash(m) > hash) 811 q = m - 1; 812 else 813 p = m + 1; 814 } 815 816 if (0) { // linear search cross check 817 unsigned n = count - 1; 818 at = entries; 819 while (n--) 820 { 821 dxtrace(printk(KERN_CONT ",")); 822 if (dx_get_hash(++at) > hash) 823 { 824 at--; 825 break; 826 } 827 } 828 assert (at == p - 1); 829 } 830 831 at = p - 1; 832 dxtrace(printk(KERN_CONT " %x->%u\n", 833 at == entries ? 0 : dx_get_hash(at), 834 dx_get_block(at))); 835 frame->entries = entries; 836 frame->at = at; 837 if (!indirect--) 838 return frame; 839 frame++; 840 frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX); 841 if (IS_ERR(frame->bh)) { 842 ret_err = (struct dx_frame *) frame->bh; 843 frame->bh = NULL; 844 goto fail; 845 } 846 entries = ((struct dx_node *) frame->bh->b_data)->entries; 847 848 if (dx_get_limit(entries) != dx_node_limit(dir)) { 849 ext4_warning_inode(dir, 850 "dx entry: limit %u != node limit %u", 851 dx_get_limit(entries), dx_node_limit(dir)); 852 goto fail; 853 } 854 } 855 fail: 856 while (frame >= frame_in) { 857 brelse(frame->bh); 858 frame--; 859 } 860 861 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR)) 862 ext4_warning_inode(dir, 863 "Corrupt directory, running e2fsck is recommended"); 864 return ret_err; 865 } 866 867 static void dx_release(struct dx_frame *frames) 868 { 869 struct dx_root_info *info; 870 int i; 871 872 if (frames[0].bh == NULL) 873 return; 874 875 info = &((struct dx_root *)frames[0].bh->b_data)->info; 876 for (i = 0; i <= info->indirect_levels; i++) { 877 if (frames[i].bh == NULL) 878 break; 879 brelse(frames[i].bh); 880 frames[i].bh = NULL; 881 } 882 } 883 884 /* 885 * This function increments the frame pointer to search the next leaf 886 * block, and reads in the necessary intervening nodes if the search 887 * should be necessary. Whether or not the search is necessary is 888 * controlled by the hash parameter. If the hash value is even, then 889 * the search is only continued if the next block starts with that 890 * hash value. This is used if we are searching for a specific file. 891 * 892 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 893 * 894 * This function returns 1 if the caller should continue to search, 895 * or 0 if it should not. If there is an error reading one of the 896 * index blocks, it will a negative error code. 897 * 898 * If start_hash is non-null, it will be filled in with the starting 899 * hash of the next page. 900 */ 901 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 902 struct dx_frame *frame, 903 struct dx_frame *frames, 904 __u32 *start_hash) 905 { 906 struct dx_frame *p; 907 struct buffer_head *bh; 908 int num_frames = 0; 909 __u32 bhash; 910 911 p = frame; 912 /* 913 * Find the next leaf page by incrementing the frame pointer. 914 * If we run out of entries in the interior node, loop around and 915 * increment pointer in the parent node. When we break out of 916 * this loop, num_frames indicates the number of interior 917 * nodes need to be read. 918 */ 919 while (1) { 920 if (++(p->at) < p->entries + dx_get_count(p->entries)) 921 break; 922 if (p == frames) 923 return 0; 924 num_frames++; 925 p--; 926 } 927 928 /* 929 * If the hash is 1, then continue only if the next page has a 930 * continuation hash of any value. This is used for readdir 931 * handling. Otherwise, check to see if the hash matches the 932 * desired contiuation hash. If it doesn't, return since 933 * there's no point to read in the successive index pages. 934 */ 935 bhash = dx_get_hash(p->at); 936 if (start_hash) 937 *start_hash = bhash; 938 if ((hash & 1) == 0) { 939 if ((bhash & ~1) != hash) 940 return 0; 941 } 942 /* 943 * If the hash is HASH_NB_ALWAYS, we always go to the next 944 * block so no check is necessary 945 */ 946 while (num_frames--) { 947 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX); 948 if (IS_ERR(bh)) 949 return PTR_ERR(bh); 950 p++; 951 brelse(p->bh); 952 p->bh = bh; 953 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 954 } 955 return 1; 956 } 957 958 959 /* 960 * This function fills a red-black tree with information from a 961 * directory block. It returns the number directory entries loaded 962 * into the tree. If there is an error it is returned in err. 963 */ 964 static int htree_dirblock_to_tree(struct file *dir_file, 965 struct inode *dir, ext4_lblk_t block, 966 struct dx_hash_info *hinfo, 967 __u32 start_hash, __u32 start_minor_hash) 968 { 969 struct buffer_head *bh; 970 struct ext4_dir_entry_2 *de, *top; 971 int err = 0, count = 0; 972 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str; 973 974 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", 975 (unsigned long)block)); 976 bh = ext4_read_dirblock(dir, block, DIRENT); 977 if (IS_ERR(bh)) 978 return PTR_ERR(bh); 979 980 de = (struct ext4_dir_entry_2 *) bh->b_data; 981 top = (struct ext4_dir_entry_2 *) ((char *) de + 982 dir->i_sb->s_blocksize - 983 EXT4_DIR_REC_LEN(0)); 984 #ifdef CONFIG_EXT4_FS_ENCRYPTION 985 /* Check if the directory is encrypted */ 986 if (ext4_encrypted_inode(dir)) { 987 err = fscrypt_get_encryption_info(dir); 988 if (err < 0) { 989 brelse(bh); 990 return err; 991 } 992 err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN, 993 &fname_crypto_str); 994 if (err < 0) { 995 brelse(bh); 996 return err; 997 } 998 } 999 #endif 1000 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { 1001 if (ext4_check_dir_entry(dir, NULL, de, bh, 1002 bh->b_data, bh->b_size, 1003 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb)) 1004 + ((char *)de - bh->b_data))) { 1005 /* silently ignore the rest of the block */ 1006 break; 1007 } 1008 ext4fs_dirhash(de->name, de->name_len, hinfo); 1009 if ((hinfo->hash < start_hash) || 1010 ((hinfo->hash == start_hash) && 1011 (hinfo->minor_hash < start_minor_hash))) 1012 continue; 1013 if (de->inode == 0) 1014 continue; 1015 if (!ext4_encrypted_inode(dir)) { 1016 tmp_str.name = de->name; 1017 tmp_str.len = de->name_len; 1018 err = ext4_htree_store_dirent(dir_file, 1019 hinfo->hash, hinfo->minor_hash, de, 1020 &tmp_str); 1021 } else { 1022 int save_len = fname_crypto_str.len; 1023 struct fscrypt_str de_name = FSTR_INIT(de->name, 1024 de->name_len); 1025 1026 /* Directory is encrypted */ 1027 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash, 1028 hinfo->minor_hash, &de_name, 1029 &fname_crypto_str); 1030 if (err) { 1031 count = err; 1032 goto errout; 1033 } 1034 err = ext4_htree_store_dirent(dir_file, 1035 hinfo->hash, hinfo->minor_hash, de, 1036 &fname_crypto_str); 1037 fname_crypto_str.len = save_len; 1038 } 1039 if (err != 0) { 1040 count = err; 1041 goto errout; 1042 } 1043 count++; 1044 } 1045 errout: 1046 brelse(bh); 1047 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1048 fscrypt_fname_free_buffer(&fname_crypto_str); 1049 #endif 1050 return count; 1051 } 1052 1053 1054 /* 1055 * This function fills a red-black tree with information from a 1056 * directory. We start scanning the directory in hash order, starting 1057 * at start_hash and start_minor_hash. 1058 * 1059 * This function returns the number of entries inserted into the tree, 1060 * or a negative error code. 1061 */ 1062 int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, 1063 __u32 start_minor_hash, __u32 *next_hash) 1064 { 1065 struct dx_hash_info hinfo; 1066 struct ext4_dir_entry_2 *de; 1067 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1068 struct inode *dir; 1069 ext4_lblk_t block; 1070 int count = 0; 1071 int ret, err; 1072 __u32 hashval; 1073 struct fscrypt_str tmp_str; 1074 1075 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n", 1076 start_hash, start_minor_hash)); 1077 dir = file_inode(dir_file); 1078 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) { 1079 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1080 if (hinfo.hash_version <= DX_HASH_TEA) 1081 hinfo.hash_version += 1082 EXT4_SB(dir->i_sb)->s_hash_unsigned; 1083 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1084 if (ext4_has_inline_data(dir)) { 1085 int has_inline_data = 1; 1086 count = htree_inlinedir_to_tree(dir_file, dir, 0, 1087 &hinfo, start_hash, 1088 start_minor_hash, 1089 &has_inline_data); 1090 if (has_inline_data) { 1091 *next_hash = ~0; 1092 return count; 1093 } 1094 } 1095 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 1096 start_hash, start_minor_hash); 1097 *next_hash = ~0; 1098 return count; 1099 } 1100 hinfo.hash = start_hash; 1101 hinfo.minor_hash = 0; 1102 frame = dx_probe(NULL, dir, &hinfo, frames); 1103 if (IS_ERR(frame)) 1104 return PTR_ERR(frame); 1105 1106 /* Add '.' and '..' from the htree header */ 1107 if (!start_hash && !start_minor_hash) { 1108 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1109 tmp_str.name = de->name; 1110 tmp_str.len = de->name_len; 1111 err = ext4_htree_store_dirent(dir_file, 0, 0, 1112 de, &tmp_str); 1113 if (err != 0) 1114 goto errout; 1115 count++; 1116 } 1117 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 1118 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1119 de = ext4_next_entry(de, dir->i_sb->s_blocksize); 1120 tmp_str.name = de->name; 1121 tmp_str.len = de->name_len; 1122 err = ext4_htree_store_dirent(dir_file, 2, 0, 1123 de, &tmp_str); 1124 if (err != 0) 1125 goto errout; 1126 count++; 1127 } 1128 1129 while (1) { 1130 if (fatal_signal_pending(current)) { 1131 err = -ERESTARTSYS; 1132 goto errout; 1133 } 1134 cond_resched(); 1135 block = dx_get_block(frame->at); 1136 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 1137 start_hash, start_minor_hash); 1138 if (ret < 0) { 1139 err = ret; 1140 goto errout; 1141 } 1142 count += ret; 1143 hashval = ~0; 1144 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS, 1145 frame, frames, &hashval); 1146 *next_hash = hashval; 1147 if (ret < 0) { 1148 err = ret; 1149 goto errout; 1150 } 1151 /* 1152 * Stop if: (a) there are no more entries, or 1153 * (b) we have inserted at least one entry and the 1154 * next hash value is not a continuation 1155 */ 1156 if ((ret == 0) || 1157 (count && ((hashval & 1) == 0))) 1158 break; 1159 } 1160 dx_release(frames); 1161 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, " 1162 "next hash: %x\n", count, *next_hash)); 1163 return count; 1164 errout: 1165 dx_release(frames); 1166 return (err); 1167 } 1168 1169 static inline int search_dirblock(struct buffer_head *bh, 1170 struct inode *dir, 1171 struct ext4_filename *fname, 1172 unsigned int offset, 1173 struct ext4_dir_entry_2 **res_dir) 1174 { 1175 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir, 1176 fname, offset, res_dir); 1177 } 1178 1179 /* 1180 * Directory block splitting, compacting 1181 */ 1182 1183 /* 1184 * Create map of hash values, offsets, and sizes, stored at end of block. 1185 * Returns number of entries mapped. 1186 */ 1187 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 1188 unsigned blocksize, struct dx_hash_info *hinfo, 1189 struct dx_map_entry *map_tail) 1190 { 1191 int count = 0; 1192 char *base = (char *) de; 1193 struct dx_hash_info h = *hinfo; 1194 1195 while ((char *) de < base + blocksize) { 1196 if (de->name_len && de->inode) { 1197 ext4fs_dirhash(de->name, de->name_len, &h); 1198 map_tail--; 1199 map_tail->hash = h.hash; 1200 map_tail->offs = ((char *) de - base)>>2; 1201 map_tail->size = le16_to_cpu(de->rec_len); 1202 count++; 1203 cond_resched(); 1204 } 1205 /* XXX: do we need to check rec_len == 0 case? -Chris */ 1206 de = ext4_next_entry(de, blocksize); 1207 } 1208 return count; 1209 } 1210 1211 /* Sort map by hash value */ 1212 static void dx_sort_map (struct dx_map_entry *map, unsigned count) 1213 { 1214 struct dx_map_entry *p, *q, *top = map + count - 1; 1215 int more; 1216 /* Combsort until bubble sort doesn't suck */ 1217 while (count > 2) { 1218 count = count*10/13; 1219 if (count - 9 < 2) /* 9, 10 -> 11 */ 1220 count = 11; 1221 for (p = top, q = p - count; q >= map; p--, q--) 1222 if (p->hash < q->hash) 1223 swap(*p, *q); 1224 } 1225 /* Garden variety bubble sort */ 1226 do { 1227 more = 0; 1228 q = top; 1229 while (q-- > map) { 1230 if (q[1].hash >= q[0].hash) 1231 continue; 1232 swap(*(q+1), *q); 1233 more = 1; 1234 } 1235 } while(more); 1236 } 1237 1238 static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) 1239 { 1240 struct dx_entry *entries = frame->entries; 1241 struct dx_entry *old = frame->at, *new = old + 1; 1242 int count = dx_get_count(entries); 1243 1244 assert(count < dx_get_limit(entries)); 1245 assert(old < entries + count); 1246 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 1247 dx_set_hash(new, hash); 1248 dx_set_block(new, block); 1249 dx_set_count(entries, count + 1); 1250 } 1251 1252 /* 1253 * Test whether a directory entry matches the filename being searched for. 1254 * 1255 * Return: %true if the directory entry matches, otherwise %false. 1256 */ 1257 static inline bool ext4_match(const struct ext4_filename *fname, 1258 const struct ext4_dir_entry_2 *de) 1259 { 1260 struct fscrypt_name f; 1261 1262 if (!de->inode) 1263 return false; 1264 1265 f.usr_fname = fname->usr_fname; 1266 f.disk_name = fname->disk_name; 1267 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1268 f.crypto_buf = fname->crypto_buf; 1269 #endif 1270 return fscrypt_match_name(&f, de->name, de->name_len); 1271 } 1272 1273 /* 1274 * Returns 0 if not found, -1 on failure, and 1 on success 1275 */ 1276 int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, 1277 struct inode *dir, struct ext4_filename *fname, 1278 unsigned int offset, struct ext4_dir_entry_2 **res_dir) 1279 { 1280 struct ext4_dir_entry_2 * de; 1281 char * dlimit; 1282 int de_len; 1283 1284 de = (struct ext4_dir_entry_2 *)search_buf; 1285 dlimit = search_buf + buf_size; 1286 while ((char *) de < dlimit) { 1287 /* this code is executed quadratically often */ 1288 /* do minimal checking `by hand' */ 1289 if ((char *) de + de->name_len <= dlimit && 1290 ext4_match(fname, de)) { 1291 /* found a match - just to be sure, do 1292 * a full check */ 1293 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, 1294 bh->b_size, offset)) 1295 return -1; 1296 *res_dir = de; 1297 return 1; 1298 } 1299 /* prevent looping on a bad block */ 1300 de_len = ext4_rec_len_from_disk(de->rec_len, 1301 dir->i_sb->s_blocksize); 1302 if (de_len <= 0) 1303 return -1; 1304 offset += de_len; 1305 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); 1306 } 1307 return 0; 1308 } 1309 1310 static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block, 1311 struct ext4_dir_entry *de) 1312 { 1313 struct super_block *sb = dir->i_sb; 1314 1315 if (!is_dx(dir)) 1316 return 0; 1317 if (block == 0) 1318 return 1; 1319 if (de->inode == 0 && 1320 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) == 1321 sb->s_blocksize) 1322 return 1; 1323 return 0; 1324 } 1325 1326 /* 1327 * ext4_find_entry() 1328 * 1329 * finds an entry in the specified directory with the wanted name. It 1330 * returns the cache buffer in which the entry was found, and the entry 1331 * itself (as a parameter - res_dir). It does NOT read the inode of the 1332 * entry - you'll have to do that yourself if you want to. 1333 * 1334 * The returned buffer_head has ->b_count elevated. The caller is expected 1335 * to brelse() it when appropriate. 1336 */ 1337 static struct buffer_head * ext4_find_entry (struct inode *dir, 1338 const struct qstr *d_name, 1339 struct ext4_dir_entry_2 **res_dir, 1340 int *inlined) 1341 { 1342 struct super_block *sb; 1343 struct buffer_head *bh_use[NAMEI_RA_SIZE]; 1344 struct buffer_head *bh, *ret = NULL; 1345 ext4_lblk_t start, block, b; 1346 const u8 *name = d_name->name; 1347 int ra_max = 0; /* Number of bh's in the readahead 1348 buffer, bh_use[] */ 1349 int ra_ptr = 0; /* Current index into readahead 1350 buffer */ 1351 int num = 0; 1352 ext4_lblk_t nblocks; 1353 int i, namelen, retval; 1354 struct ext4_filename fname; 1355 1356 *res_dir = NULL; 1357 sb = dir->i_sb; 1358 namelen = d_name->len; 1359 if (namelen > EXT4_NAME_LEN) 1360 return NULL; 1361 1362 retval = ext4_fname_setup_filename(dir, d_name, 1, &fname); 1363 if (retval == -ENOENT) 1364 return NULL; 1365 if (retval) 1366 return ERR_PTR(retval); 1367 1368 if (ext4_has_inline_data(dir)) { 1369 int has_inline_data = 1; 1370 ret = ext4_find_inline_entry(dir, &fname, res_dir, 1371 &has_inline_data); 1372 if (has_inline_data) { 1373 if (inlined) 1374 *inlined = 1; 1375 goto cleanup_and_exit; 1376 } 1377 } 1378 1379 if ((namelen <= 2) && (name[0] == '.') && 1380 (name[1] == '.' || name[1] == '\0')) { 1381 /* 1382 * "." or ".." will only be in the first block 1383 * NFS may look up ".."; "." should be handled by the VFS 1384 */ 1385 block = start = 0; 1386 nblocks = 1; 1387 goto restart; 1388 } 1389 if (is_dx(dir)) { 1390 ret = ext4_dx_find_entry(dir, &fname, res_dir); 1391 /* 1392 * On success, or if the error was file not found, 1393 * return. Otherwise, fall back to doing a search the 1394 * old fashioned way. 1395 */ 1396 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) 1397 goto cleanup_and_exit; 1398 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " 1399 "falling back\n")); 1400 } 1401 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1402 start = EXT4_I(dir)->i_dir_start_lookup; 1403 if (start >= nblocks) 1404 start = 0; 1405 block = start; 1406 restart: 1407 do { 1408 /* 1409 * We deal with the read-ahead logic here. 1410 */ 1411 if (ra_ptr >= ra_max) { 1412 /* Refill the readahead buffer */ 1413 ra_ptr = 0; 1414 b = block; 1415 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) { 1416 /* 1417 * Terminate if we reach the end of the 1418 * directory and must wrap, or if our 1419 * search has finished at this block. 1420 */ 1421 if (b >= nblocks || (num && block == start)) { 1422 bh_use[ra_max] = NULL; 1423 break; 1424 } 1425 num++; 1426 bh = ext4_getblk(NULL, dir, b++, 0); 1427 if (IS_ERR(bh)) { 1428 if (ra_max == 0) { 1429 ret = bh; 1430 goto cleanup_and_exit; 1431 } 1432 break; 1433 } 1434 bh_use[ra_max] = bh; 1435 if (bh) 1436 ll_rw_block(REQ_OP_READ, 1437 REQ_META | REQ_PRIO, 1438 1, &bh); 1439 } 1440 } 1441 if ((bh = bh_use[ra_ptr++]) == NULL) 1442 goto next; 1443 wait_on_buffer(bh); 1444 if (!buffer_uptodate(bh)) { 1445 EXT4_ERROR_INODE(dir, "reading directory lblock %lu", 1446 (unsigned long) block); 1447 brelse(bh); 1448 ret = ERR_PTR(-EIO); 1449 goto cleanup_and_exit; 1450 } 1451 if (!buffer_verified(bh) && 1452 !is_dx_internal_node(dir, block, 1453 (struct ext4_dir_entry *)bh->b_data) && 1454 !ext4_dirent_csum_verify(dir, 1455 (struct ext4_dir_entry *)bh->b_data)) { 1456 EXT4_ERROR_INODE(dir, "checksumming directory " 1457 "block %lu", (unsigned long)block); 1458 brelse(bh); 1459 ret = ERR_PTR(-EFSBADCRC); 1460 goto cleanup_and_exit; 1461 } 1462 set_buffer_verified(bh); 1463 i = search_dirblock(bh, dir, &fname, 1464 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); 1465 if (i == 1) { 1466 EXT4_I(dir)->i_dir_start_lookup = block; 1467 ret = bh; 1468 goto cleanup_and_exit; 1469 } else { 1470 brelse(bh); 1471 if (i < 0) 1472 goto cleanup_and_exit; 1473 } 1474 next: 1475 if (++block >= nblocks) 1476 block = 0; 1477 } while (block != start); 1478 1479 /* 1480 * If the directory has grown while we were searching, then 1481 * search the last part of the directory before giving up. 1482 */ 1483 block = nblocks; 1484 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1485 if (block < nblocks) { 1486 start = 0; 1487 goto restart; 1488 } 1489 1490 cleanup_and_exit: 1491 /* Clean up the read-ahead blocks */ 1492 for (; ra_ptr < ra_max; ra_ptr++) 1493 brelse(bh_use[ra_ptr]); 1494 ext4_fname_free_filename(&fname); 1495 return ret; 1496 } 1497 1498 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 1499 struct ext4_filename *fname, 1500 struct ext4_dir_entry_2 **res_dir) 1501 { 1502 struct super_block * sb = dir->i_sb; 1503 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1504 struct buffer_head *bh; 1505 ext4_lblk_t block; 1506 int retval; 1507 1508 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1509 *res_dir = NULL; 1510 #endif 1511 frame = dx_probe(fname, dir, NULL, frames); 1512 if (IS_ERR(frame)) 1513 return (struct buffer_head *) frame; 1514 do { 1515 block = dx_get_block(frame->at); 1516 bh = ext4_read_dirblock(dir, block, DIRENT); 1517 if (IS_ERR(bh)) 1518 goto errout; 1519 1520 retval = search_dirblock(bh, dir, fname, 1521 block << EXT4_BLOCK_SIZE_BITS(sb), 1522 res_dir); 1523 if (retval == 1) 1524 goto success; 1525 brelse(bh); 1526 if (retval == -1) { 1527 bh = ERR_PTR(ERR_BAD_DX_DIR); 1528 goto errout; 1529 } 1530 1531 /* Check to see if we should continue to search */ 1532 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame, 1533 frames, NULL); 1534 if (retval < 0) { 1535 ext4_warning_inode(dir, 1536 "error %d reading directory index block", 1537 retval); 1538 bh = ERR_PTR(retval); 1539 goto errout; 1540 } 1541 } while (retval == 1); 1542 1543 bh = NULL; 1544 errout: 1545 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name)); 1546 success: 1547 dx_release(frames); 1548 return bh; 1549 } 1550 1551 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 1552 { 1553 struct inode *inode; 1554 struct ext4_dir_entry_2 *de; 1555 struct buffer_head *bh; 1556 1557 if (ext4_encrypted_inode(dir)) { 1558 int res = fscrypt_get_encryption_info(dir); 1559 1560 /* 1561 * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is 1562 * created while the directory was encrypted and we 1563 * have access to the key. 1564 */ 1565 if (fscrypt_has_encryption_key(dir)) 1566 fscrypt_set_encrypted_dentry(dentry); 1567 fscrypt_set_d_op(dentry); 1568 if (res && res != -ENOKEY) 1569 return ERR_PTR(res); 1570 } 1571 1572 if (dentry->d_name.len > EXT4_NAME_LEN) 1573 return ERR_PTR(-ENAMETOOLONG); 1574 1575 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 1576 if (IS_ERR(bh)) 1577 return (struct dentry *) bh; 1578 inode = NULL; 1579 if (bh) { 1580 __u32 ino = le32_to_cpu(de->inode); 1581 brelse(bh); 1582 if (!ext4_valid_inum(dir->i_sb, ino)) { 1583 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); 1584 return ERR_PTR(-EFSCORRUPTED); 1585 } 1586 if (unlikely(ino == dir->i_ino)) { 1587 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir", 1588 dentry); 1589 return ERR_PTR(-EFSCORRUPTED); 1590 } 1591 inode = ext4_iget_normal(dir->i_sb, ino); 1592 if (inode == ERR_PTR(-ESTALE)) { 1593 EXT4_ERROR_INODE(dir, 1594 "deleted inode referenced: %u", 1595 ino); 1596 return ERR_PTR(-EFSCORRUPTED); 1597 } 1598 if (!IS_ERR(inode) && ext4_encrypted_inode(dir) && 1599 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && 1600 !fscrypt_has_permitted_context(dir, inode)) { 1601 ext4_warning(inode->i_sb, 1602 "Inconsistent encryption contexts: %lu/%lu", 1603 dir->i_ino, inode->i_ino); 1604 iput(inode); 1605 return ERR_PTR(-EPERM); 1606 } 1607 } 1608 return d_splice_alias(inode, dentry); 1609 } 1610 1611 1612 struct dentry *ext4_get_parent(struct dentry *child) 1613 { 1614 __u32 ino; 1615 static const struct qstr dotdot = QSTR_INIT("..", 2); 1616 struct ext4_dir_entry_2 * de; 1617 struct buffer_head *bh; 1618 1619 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL); 1620 if (IS_ERR(bh)) 1621 return (struct dentry *) bh; 1622 if (!bh) 1623 return ERR_PTR(-ENOENT); 1624 ino = le32_to_cpu(de->inode); 1625 brelse(bh); 1626 1627 if (!ext4_valid_inum(child->d_sb, ino)) { 1628 EXT4_ERROR_INODE(d_inode(child), 1629 "bad parent inode number: %u", ino); 1630 return ERR_PTR(-EFSCORRUPTED); 1631 } 1632 1633 return d_obtain_alias(ext4_iget_normal(child->d_sb, ino)); 1634 } 1635 1636 /* 1637 * Move count entries from end of map between two memory locations. 1638 * Returns pointer to last entry moved. 1639 */ 1640 static struct ext4_dir_entry_2 * 1641 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, 1642 unsigned blocksize) 1643 { 1644 unsigned rec_len = 0; 1645 1646 while (count--) { 1647 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) 1648 (from + (map->offs<<2)); 1649 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1650 memcpy (to, de, rec_len); 1651 ((struct ext4_dir_entry_2 *) to)->rec_len = 1652 ext4_rec_len_to_disk(rec_len, blocksize); 1653 de->inode = 0; 1654 map++; 1655 to += rec_len; 1656 } 1657 return (struct ext4_dir_entry_2 *) (to - rec_len); 1658 } 1659 1660 /* 1661 * Compact each dir entry in the range to the minimal rec_len. 1662 * Returns pointer to last entry in range. 1663 */ 1664 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) 1665 { 1666 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; 1667 unsigned rec_len = 0; 1668 1669 prev = to = de; 1670 while ((char*)de < base + blocksize) { 1671 next = ext4_next_entry(de, blocksize); 1672 if (de->inode && de->name_len) { 1673 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1674 if (de > to) 1675 memmove(to, de, rec_len); 1676 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); 1677 prev = to; 1678 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); 1679 } 1680 de = next; 1681 } 1682 return prev; 1683 } 1684 1685 /* 1686 * Split a full leaf block to make room for a new dir entry. 1687 * Allocate a new block, and move entries so that they are approx. equally full. 1688 * Returns pointer to de in block into which the new entry will be inserted. 1689 */ 1690 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1691 struct buffer_head **bh,struct dx_frame *frame, 1692 struct dx_hash_info *hinfo) 1693 { 1694 unsigned blocksize = dir->i_sb->s_blocksize; 1695 unsigned count, continued; 1696 struct buffer_head *bh2; 1697 ext4_lblk_t newblock; 1698 u32 hash2; 1699 struct dx_map_entry *map; 1700 char *data1 = (*bh)->b_data, *data2; 1701 unsigned split, move, size; 1702 struct ext4_dir_entry_2 *de = NULL, *de2; 1703 struct ext4_dir_entry_tail *t; 1704 int csum_size = 0; 1705 int err = 0, i; 1706 1707 if (ext4_has_metadata_csum(dir->i_sb)) 1708 csum_size = sizeof(struct ext4_dir_entry_tail); 1709 1710 bh2 = ext4_append(handle, dir, &newblock); 1711 if (IS_ERR(bh2)) { 1712 brelse(*bh); 1713 *bh = NULL; 1714 return (struct ext4_dir_entry_2 *) bh2; 1715 } 1716 1717 BUFFER_TRACE(*bh, "get_write_access"); 1718 err = ext4_journal_get_write_access(handle, *bh); 1719 if (err) 1720 goto journal_error; 1721 1722 BUFFER_TRACE(frame->bh, "get_write_access"); 1723 err = ext4_journal_get_write_access(handle, frame->bh); 1724 if (err) 1725 goto journal_error; 1726 1727 data2 = bh2->b_data; 1728 1729 /* create map in the end of data2 block */ 1730 map = (struct dx_map_entry *) (data2 + blocksize); 1731 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1, 1732 blocksize, hinfo, map); 1733 map -= count; 1734 dx_sort_map(map, count); 1735 /* Split the existing block in the middle, size-wise */ 1736 size = 0; 1737 move = 0; 1738 for (i = count-1; i >= 0; i--) { 1739 /* is more than half of this entry in 2nd half of the block? */ 1740 if (size + map[i].size/2 > blocksize/2) 1741 break; 1742 size += map[i].size; 1743 move++; 1744 } 1745 /* map index at which we will split */ 1746 split = count - move; 1747 hash2 = map[split].hash; 1748 continued = hash2 == map[split - 1].hash; 1749 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", 1750 (unsigned long)dx_get_block(frame->at), 1751 hash2, split, count-split)); 1752 1753 /* Fancy dance to stay within two buffers */ 1754 de2 = dx_move_dirents(data1, data2, map + split, count - split, 1755 blocksize); 1756 de = dx_pack_dirents(data1, blocksize); 1757 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1758 (char *) de, 1759 blocksize); 1760 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - 1761 (char *) de2, 1762 blocksize); 1763 if (csum_size) { 1764 t = EXT4_DIRENT_TAIL(data2, blocksize); 1765 initialize_dirent_tail(t, blocksize); 1766 1767 t = EXT4_DIRENT_TAIL(data1, blocksize); 1768 initialize_dirent_tail(t, blocksize); 1769 } 1770 1771 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1, 1772 blocksize, 1)); 1773 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2, 1774 blocksize, 1)); 1775 1776 /* Which block gets the new entry? */ 1777 if (hinfo->hash >= hash2) { 1778 swap(*bh, bh2); 1779 de = de2; 1780 } 1781 dx_insert_block(frame, hash2 + continued, newblock); 1782 err = ext4_handle_dirty_dirent_node(handle, dir, bh2); 1783 if (err) 1784 goto journal_error; 1785 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1786 if (err) 1787 goto journal_error; 1788 brelse(bh2); 1789 dxtrace(dx_show_index("frame", frame->entries)); 1790 return de; 1791 1792 journal_error: 1793 brelse(*bh); 1794 brelse(bh2); 1795 *bh = NULL; 1796 ext4_std_error(dir->i_sb, err); 1797 return ERR_PTR(err); 1798 } 1799 1800 int ext4_find_dest_de(struct inode *dir, struct inode *inode, 1801 struct buffer_head *bh, 1802 void *buf, int buf_size, 1803 struct ext4_filename *fname, 1804 struct ext4_dir_entry_2 **dest_de) 1805 { 1806 struct ext4_dir_entry_2 *de; 1807 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname)); 1808 int nlen, rlen; 1809 unsigned int offset = 0; 1810 char *top; 1811 1812 de = (struct ext4_dir_entry_2 *)buf; 1813 top = buf + buf_size - reclen; 1814 while ((char *) de <= top) { 1815 if (ext4_check_dir_entry(dir, NULL, de, bh, 1816 buf, buf_size, offset)) 1817 return -EFSCORRUPTED; 1818 if (ext4_match(fname, de)) 1819 return -EEXIST; 1820 nlen = EXT4_DIR_REC_LEN(de->name_len); 1821 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1822 if ((de->inode ? rlen - nlen : rlen) >= reclen) 1823 break; 1824 de = (struct ext4_dir_entry_2 *)((char *)de + rlen); 1825 offset += rlen; 1826 } 1827 if ((char *) de > top) 1828 return -ENOSPC; 1829 1830 *dest_de = de; 1831 return 0; 1832 } 1833 1834 void ext4_insert_dentry(struct inode *inode, 1835 struct ext4_dir_entry_2 *de, 1836 int buf_size, 1837 struct ext4_filename *fname) 1838 { 1839 1840 int nlen, rlen; 1841 1842 nlen = EXT4_DIR_REC_LEN(de->name_len); 1843 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1844 if (de->inode) { 1845 struct ext4_dir_entry_2 *de1 = 1846 (struct ext4_dir_entry_2 *)((char *)de + nlen); 1847 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); 1848 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); 1849 de = de1; 1850 } 1851 de->file_type = EXT4_FT_UNKNOWN; 1852 de->inode = cpu_to_le32(inode->i_ino); 1853 ext4_set_de_type(inode->i_sb, de, inode->i_mode); 1854 de->name_len = fname_len(fname); 1855 memcpy(de->name, fname_name(fname), fname_len(fname)); 1856 } 1857 1858 /* 1859 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1860 * it points to a directory entry which is guaranteed to be large 1861 * enough for new directory entry. If de is NULL, then 1862 * add_dirent_to_buf will attempt search the directory block for 1863 * space. It will return -ENOSPC if no space is available, and -EIO 1864 * and -EEXIST if directory entry already exists. 1865 */ 1866 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname, 1867 struct inode *dir, 1868 struct inode *inode, struct ext4_dir_entry_2 *de, 1869 struct buffer_head *bh) 1870 { 1871 unsigned int blocksize = dir->i_sb->s_blocksize; 1872 int csum_size = 0; 1873 int err; 1874 1875 if (ext4_has_metadata_csum(inode->i_sb)) 1876 csum_size = sizeof(struct ext4_dir_entry_tail); 1877 1878 if (!de) { 1879 err = ext4_find_dest_de(dir, inode, bh, bh->b_data, 1880 blocksize - csum_size, fname, &de); 1881 if (err) 1882 return err; 1883 } 1884 BUFFER_TRACE(bh, "get_write_access"); 1885 err = ext4_journal_get_write_access(handle, bh); 1886 if (err) { 1887 ext4_std_error(dir->i_sb, err); 1888 return err; 1889 } 1890 1891 /* By now the buffer is marked for journaling */ 1892 ext4_insert_dentry(inode, de, blocksize, fname); 1893 1894 /* 1895 * XXX shouldn't update any times until successful 1896 * completion of syscall, but too many callers depend 1897 * on this. 1898 * 1899 * XXX similarly, too many callers depend on 1900 * ext4_new_inode() setting the times, but error 1901 * recovery deletes the inode, so the worst that can 1902 * happen is that the times are slightly out of date 1903 * and/or different from the directory change time. 1904 */ 1905 dir->i_mtime = dir->i_ctime = current_time(dir); 1906 ext4_update_dx_flag(dir); 1907 inode_inc_iversion(dir); 1908 ext4_mark_inode_dirty(handle, dir); 1909 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 1910 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 1911 if (err) 1912 ext4_std_error(dir->i_sb, err); 1913 return 0; 1914 } 1915 1916 /* 1917 * This converts a one block unindexed directory to a 3 block indexed 1918 * directory, and adds the dentry to the indexed directory. 1919 */ 1920 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, 1921 struct inode *dir, 1922 struct inode *inode, struct buffer_head *bh) 1923 { 1924 struct buffer_head *bh2; 1925 struct dx_root *root; 1926 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1927 struct dx_entry *entries; 1928 struct ext4_dir_entry_2 *de, *de2; 1929 struct ext4_dir_entry_tail *t; 1930 char *data1, *top; 1931 unsigned len; 1932 int retval; 1933 unsigned blocksize; 1934 ext4_lblk_t block; 1935 struct fake_dirent *fde; 1936 int csum_size = 0; 1937 1938 if (ext4_has_metadata_csum(inode->i_sb)) 1939 csum_size = sizeof(struct ext4_dir_entry_tail); 1940 1941 blocksize = dir->i_sb->s_blocksize; 1942 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); 1943 BUFFER_TRACE(bh, "get_write_access"); 1944 retval = ext4_journal_get_write_access(handle, bh); 1945 if (retval) { 1946 ext4_std_error(dir->i_sb, retval); 1947 brelse(bh); 1948 return retval; 1949 } 1950 root = (struct dx_root *) bh->b_data; 1951 1952 /* The 0th block becomes the root, move the dirents out */ 1953 fde = &root->dotdot; 1954 de = (struct ext4_dir_entry_2 *)((char *)fde + 1955 ext4_rec_len_from_disk(fde->rec_len, blocksize)); 1956 if ((char *) de >= (((char *) root) + blocksize)) { 1957 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); 1958 brelse(bh); 1959 return -EFSCORRUPTED; 1960 } 1961 len = ((char *) root) + (blocksize - csum_size) - (char *) de; 1962 1963 /* Allocate new block for the 0th block's dirents */ 1964 bh2 = ext4_append(handle, dir, &block); 1965 if (IS_ERR(bh2)) { 1966 brelse(bh); 1967 return PTR_ERR(bh2); 1968 } 1969 ext4_set_inode_flag(dir, EXT4_INODE_INDEX); 1970 data1 = bh2->b_data; 1971 1972 memcpy (data1, de, len); 1973 de = (struct ext4_dir_entry_2 *) data1; 1974 top = data1 + len; 1975 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) 1976 de = de2; 1977 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1978 (char *) de, 1979 blocksize); 1980 1981 if (csum_size) { 1982 t = EXT4_DIRENT_TAIL(data1, blocksize); 1983 initialize_dirent_tail(t, blocksize); 1984 } 1985 1986 /* Initialize the root; the dot dirents already exist */ 1987 de = (struct ext4_dir_entry_2 *) (&root->dotdot); 1988 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), 1989 blocksize); 1990 memset (&root->info, 0, sizeof(root->info)); 1991 root->info.info_length = sizeof(root->info); 1992 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1993 entries = root->entries; 1994 dx_set_block(entries, 1); 1995 dx_set_count(entries, 1); 1996 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); 1997 1998 /* Initialize as for dx_probe */ 1999 fname->hinfo.hash_version = root->info.hash_version; 2000 if (fname->hinfo.hash_version <= DX_HASH_TEA) 2001 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 2002 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 2003 ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo); 2004 2005 memset(frames, 0, sizeof(frames)); 2006 frame = frames; 2007 frame->entries = entries; 2008 frame->at = entries; 2009 frame->bh = bh; 2010 2011 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2012 if (retval) 2013 goto out_frames; 2014 retval = ext4_handle_dirty_dirent_node(handle, dir, bh2); 2015 if (retval) 2016 goto out_frames; 2017 2018 de = do_split(handle,dir, &bh2, frame, &fname->hinfo); 2019 if (IS_ERR(de)) { 2020 retval = PTR_ERR(de); 2021 goto out_frames; 2022 } 2023 2024 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2); 2025 out_frames: 2026 /* 2027 * Even if the block split failed, we have to properly write 2028 * out all the changes we did so far. Otherwise we can end up 2029 * with corrupted filesystem. 2030 */ 2031 if (retval) 2032 ext4_mark_inode_dirty(handle, dir); 2033 dx_release(frames); 2034 brelse(bh2); 2035 return retval; 2036 } 2037 2038 /* 2039 * ext4_add_entry() 2040 * 2041 * adds a file entry to the specified directory, using the same 2042 * semantics as ext4_find_entry(). It returns NULL if it failed. 2043 * 2044 * NOTE!! The inode part of 'de' is left at 0 - which means you 2045 * may not sleep between calling this and putting something into 2046 * the entry, as someone else might have used it while you slept. 2047 */ 2048 static int ext4_add_entry(handle_t *handle, struct dentry *dentry, 2049 struct inode *inode) 2050 { 2051 struct inode *dir = d_inode(dentry->d_parent); 2052 struct buffer_head *bh = NULL; 2053 struct ext4_dir_entry_2 *de; 2054 struct ext4_dir_entry_tail *t; 2055 struct super_block *sb; 2056 struct ext4_filename fname; 2057 int retval; 2058 int dx_fallback=0; 2059 unsigned blocksize; 2060 ext4_lblk_t block, blocks; 2061 int csum_size = 0; 2062 2063 if (ext4_has_metadata_csum(inode->i_sb)) 2064 csum_size = sizeof(struct ext4_dir_entry_tail); 2065 2066 sb = dir->i_sb; 2067 blocksize = sb->s_blocksize; 2068 if (!dentry->d_name.len) 2069 return -EINVAL; 2070 2071 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname); 2072 if (retval) 2073 return retval; 2074 2075 if (ext4_has_inline_data(dir)) { 2076 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode); 2077 if (retval < 0) 2078 goto out; 2079 if (retval == 1) { 2080 retval = 0; 2081 goto out; 2082 } 2083 } 2084 2085 if (is_dx(dir)) { 2086 retval = ext4_dx_add_entry(handle, &fname, dir, inode); 2087 if (!retval || (retval != ERR_BAD_DX_DIR)) 2088 goto out; 2089 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); 2090 dx_fallback++; 2091 ext4_mark_inode_dirty(handle, dir); 2092 } 2093 blocks = dir->i_size >> sb->s_blocksize_bits; 2094 for (block = 0; block < blocks; block++) { 2095 bh = ext4_read_dirblock(dir, block, DIRENT); 2096 if (IS_ERR(bh)) { 2097 retval = PTR_ERR(bh); 2098 bh = NULL; 2099 goto out; 2100 } 2101 retval = add_dirent_to_buf(handle, &fname, dir, inode, 2102 NULL, bh); 2103 if (retval != -ENOSPC) 2104 goto out; 2105 2106 if (blocks == 1 && !dx_fallback && 2107 ext4_has_feature_dir_index(sb)) { 2108 retval = make_indexed_dir(handle, &fname, dir, 2109 inode, bh); 2110 bh = NULL; /* make_indexed_dir releases bh */ 2111 goto out; 2112 } 2113 brelse(bh); 2114 } 2115 bh = ext4_append(handle, dir, &block); 2116 if (IS_ERR(bh)) { 2117 retval = PTR_ERR(bh); 2118 bh = NULL; 2119 goto out; 2120 } 2121 de = (struct ext4_dir_entry_2 *) bh->b_data; 2122 de->inode = 0; 2123 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize); 2124 2125 if (csum_size) { 2126 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize); 2127 initialize_dirent_tail(t, blocksize); 2128 } 2129 2130 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh); 2131 out: 2132 ext4_fname_free_filename(&fname); 2133 brelse(bh); 2134 if (retval == 0) 2135 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); 2136 return retval; 2137 } 2138 2139 /* 2140 * Returns 0 for success, or a negative error value 2141 */ 2142 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 2143 struct inode *dir, struct inode *inode) 2144 { 2145 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 2146 struct dx_entry *entries, *at; 2147 struct buffer_head *bh; 2148 struct super_block *sb = dir->i_sb; 2149 struct ext4_dir_entry_2 *de; 2150 int restart; 2151 int err; 2152 2153 again: 2154 restart = 0; 2155 frame = dx_probe(fname, dir, NULL, frames); 2156 if (IS_ERR(frame)) 2157 return PTR_ERR(frame); 2158 entries = frame->entries; 2159 at = frame->at; 2160 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT); 2161 if (IS_ERR(bh)) { 2162 err = PTR_ERR(bh); 2163 bh = NULL; 2164 goto cleanup; 2165 } 2166 2167 BUFFER_TRACE(bh, "get_write_access"); 2168 err = ext4_journal_get_write_access(handle, bh); 2169 if (err) 2170 goto journal_error; 2171 2172 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh); 2173 if (err != -ENOSPC) 2174 goto cleanup; 2175 2176 err = 0; 2177 /* Block full, should compress but for now just split */ 2178 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n", 2179 dx_get_count(entries), dx_get_limit(entries))); 2180 /* Need to split index? */ 2181 if (dx_get_count(entries) == dx_get_limit(entries)) { 2182 ext4_lblk_t newblock; 2183 int levels = frame - frames + 1; 2184 unsigned int icount; 2185 int add_level = 1; 2186 struct dx_entry *entries2; 2187 struct dx_node *node2; 2188 struct buffer_head *bh2; 2189 2190 while (frame > frames) { 2191 if (dx_get_count((frame - 1)->entries) < 2192 dx_get_limit((frame - 1)->entries)) { 2193 add_level = 0; 2194 break; 2195 } 2196 frame--; /* split higher index block */ 2197 at = frame->at; 2198 entries = frame->entries; 2199 restart = 1; 2200 } 2201 if (add_level && levels == ext4_dir_htree_level(sb)) { 2202 ext4_warning(sb, "Directory (ino: %lu) index full, " 2203 "reach max htree level :%d", 2204 dir->i_ino, levels); 2205 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) { 2206 ext4_warning(sb, "Large directory feature is " 2207 "not enabled on this " 2208 "filesystem"); 2209 } 2210 err = -ENOSPC; 2211 goto cleanup; 2212 } 2213 icount = dx_get_count(entries); 2214 bh2 = ext4_append(handle, dir, &newblock); 2215 if (IS_ERR(bh2)) { 2216 err = PTR_ERR(bh2); 2217 goto cleanup; 2218 } 2219 node2 = (struct dx_node *)(bh2->b_data); 2220 entries2 = node2->entries; 2221 memset(&node2->fake, 0, sizeof(struct fake_dirent)); 2222 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, 2223 sb->s_blocksize); 2224 BUFFER_TRACE(frame->bh, "get_write_access"); 2225 err = ext4_journal_get_write_access(handle, frame->bh); 2226 if (err) 2227 goto journal_error; 2228 if (!add_level) { 2229 unsigned icount1 = icount/2, icount2 = icount - icount1; 2230 unsigned hash2 = dx_get_hash(entries + icount1); 2231 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n", 2232 icount1, icount2)); 2233 2234 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 2235 err = ext4_journal_get_write_access(handle, 2236 (frame - 1)->bh); 2237 if (err) 2238 goto journal_error; 2239 2240 memcpy((char *) entries2, (char *) (entries + icount1), 2241 icount2 * sizeof(struct dx_entry)); 2242 dx_set_count(entries, icount1); 2243 dx_set_count(entries2, icount2); 2244 dx_set_limit(entries2, dx_node_limit(dir)); 2245 2246 /* Which index block gets the new entry? */ 2247 if (at - entries >= icount1) { 2248 frame->at = at = at - entries - icount1 + entries2; 2249 frame->entries = entries = entries2; 2250 swap(frame->bh, bh2); 2251 } 2252 dx_insert_block((frame - 1), hash2, newblock); 2253 dxtrace(dx_show_index("node", frame->entries)); 2254 dxtrace(dx_show_index("node", 2255 ((struct dx_node *) bh2->b_data)->entries)); 2256 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2257 if (err) 2258 goto journal_error; 2259 brelse (bh2); 2260 err = ext4_handle_dirty_dx_node(handle, dir, 2261 (frame - 1)->bh); 2262 if (err) 2263 goto journal_error; 2264 if (restart) { 2265 err = ext4_handle_dirty_dx_node(handle, dir, 2266 frame->bh); 2267 goto journal_error; 2268 } 2269 } else { 2270 struct dx_root *dxroot; 2271 memcpy((char *) entries2, (char *) entries, 2272 icount * sizeof(struct dx_entry)); 2273 dx_set_limit(entries2, dx_node_limit(dir)); 2274 2275 /* Set up root */ 2276 dx_set_count(entries, 1); 2277 dx_set_block(entries + 0, newblock); 2278 dxroot = (struct dx_root *)frames[0].bh->b_data; 2279 dxroot->info.indirect_levels += 1; 2280 dxtrace(printk(KERN_DEBUG 2281 "Creating %d level index...\n", 2282 info->indirect_levels)); 2283 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2284 if (err) 2285 goto journal_error; 2286 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2287 brelse(bh2); 2288 restart = 1; 2289 goto journal_error; 2290 } 2291 } 2292 de = do_split(handle, dir, &bh, frame, &fname->hinfo); 2293 if (IS_ERR(de)) { 2294 err = PTR_ERR(de); 2295 goto cleanup; 2296 } 2297 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh); 2298 goto cleanup; 2299 2300 journal_error: 2301 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */ 2302 cleanup: 2303 brelse(bh); 2304 dx_release(frames); 2305 /* @restart is true means htree-path has been changed, we need to 2306 * repeat dx_probe() to find out valid htree-path 2307 */ 2308 if (restart && err == 0) 2309 goto again; 2310 return err; 2311 } 2312 2313 /* 2314 * ext4_generic_delete_entry deletes a directory entry by merging it 2315 * with the previous entry 2316 */ 2317 int ext4_generic_delete_entry(handle_t *handle, 2318 struct inode *dir, 2319 struct ext4_dir_entry_2 *de_del, 2320 struct buffer_head *bh, 2321 void *entry_buf, 2322 int buf_size, 2323 int csum_size) 2324 { 2325 struct ext4_dir_entry_2 *de, *pde; 2326 unsigned int blocksize = dir->i_sb->s_blocksize; 2327 int i; 2328 2329 i = 0; 2330 pde = NULL; 2331 de = (struct ext4_dir_entry_2 *)entry_buf; 2332 while (i < buf_size - csum_size) { 2333 if (ext4_check_dir_entry(dir, NULL, de, bh, 2334 bh->b_data, bh->b_size, i)) 2335 return -EFSCORRUPTED; 2336 if (de == de_del) { 2337 if (pde) 2338 pde->rec_len = ext4_rec_len_to_disk( 2339 ext4_rec_len_from_disk(pde->rec_len, 2340 blocksize) + 2341 ext4_rec_len_from_disk(de->rec_len, 2342 blocksize), 2343 blocksize); 2344 else 2345 de->inode = 0; 2346 inode_inc_iversion(dir); 2347 return 0; 2348 } 2349 i += ext4_rec_len_from_disk(de->rec_len, blocksize); 2350 pde = de; 2351 de = ext4_next_entry(de, blocksize); 2352 } 2353 return -ENOENT; 2354 } 2355 2356 static int ext4_delete_entry(handle_t *handle, 2357 struct inode *dir, 2358 struct ext4_dir_entry_2 *de_del, 2359 struct buffer_head *bh) 2360 { 2361 int err, csum_size = 0; 2362 2363 if (ext4_has_inline_data(dir)) { 2364 int has_inline_data = 1; 2365 err = ext4_delete_inline_entry(handle, dir, de_del, bh, 2366 &has_inline_data); 2367 if (has_inline_data) 2368 return err; 2369 } 2370 2371 if (ext4_has_metadata_csum(dir->i_sb)) 2372 csum_size = sizeof(struct ext4_dir_entry_tail); 2373 2374 BUFFER_TRACE(bh, "get_write_access"); 2375 err = ext4_journal_get_write_access(handle, bh); 2376 if (unlikely(err)) 2377 goto out; 2378 2379 err = ext4_generic_delete_entry(handle, dir, de_del, 2380 bh, bh->b_data, 2381 dir->i_sb->s_blocksize, csum_size); 2382 if (err) 2383 goto out; 2384 2385 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 2386 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 2387 if (unlikely(err)) 2388 goto out; 2389 2390 return 0; 2391 out: 2392 if (err != -ENOENT) 2393 ext4_std_error(dir->i_sb, err); 2394 return err; 2395 } 2396 2397 /* 2398 * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2, 2399 * since this indicates that nlinks count was previously 1. 2400 */ 2401 static void ext4_inc_count(handle_t *handle, struct inode *inode) 2402 { 2403 inc_nlink(inode); 2404 if (is_dx(inode) && inode->i_nlink > 1) { 2405 /* limit is 16-bit i_links_count */ 2406 if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) { 2407 set_nlink(inode, 1); 2408 ext4_set_feature_dir_nlink(inode->i_sb); 2409 } 2410 } 2411 } 2412 2413 /* 2414 * If a directory had nlink == 1, then we should let it be 1. This indicates 2415 * directory has >EXT4_LINK_MAX subdirs. 2416 */ 2417 static void ext4_dec_count(handle_t *handle, struct inode *inode) 2418 { 2419 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) 2420 drop_nlink(inode); 2421 } 2422 2423 2424 static int ext4_add_nondir(handle_t *handle, 2425 struct dentry *dentry, struct inode *inode) 2426 { 2427 int err = ext4_add_entry(handle, dentry, inode); 2428 if (!err) { 2429 ext4_mark_inode_dirty(handle, inode); 2430 unlock_new_inode(inode); 2431 d_instantiate(dentry, inode); 2432 return 0; 2433 } 2434 drop_nlink(inode); 2435 unlock_new_inode(inode); 2436 iput(inode); 2437 return err; 2438 } 2439 2440 /* 2441 * By the time this is called, we already have created 2442 * the directory cache entry for the new file, but it 2443 * is so far negative - it has no inode. 2444 * 2445 * If the create succeeds, we fill in the inode information 2446 * with d_instantiate(). 2447 */ 2448 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, 2449 bool excl) 2450 { 2451 handle_t *handle; 2452 struct inode *inode; 2453 int err, credits, retries = 0; 2454 2455 err = dquot_initialize(dir); 2456 if (err) 2457 return err; 2458 2459 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2460 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2461 retry: 2462 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2463 NULL, EXT4_HT_DIR, credits); 2464 handle = ext4_journal_current_handle(); 2465 err = PTR_ERR(inode); 2466 if (!IS_ERR(inode)) { 2467 inode->i_op = &ext4_file_inode_operations; 2468 inode->i_fop = &ext4_file_operations; 2469 ext4_set_aops(inode); 2470 err = ext4_add_nondir(handle, dentry, inode); 2471 if (!err && IS_DIRSYNC(dir)) 2472 ext4_handle_sync(handle); 2473 } 2474 if (handle) 2475 ext4_journal_stop(handle); 2476 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2477 goto retry; 2478 return err; 2479 } 2480 2481 static int ext4_mknod(struct inode *dir, struct dentry *dentry, 2482 umode_t mode, dev_t rdev) 2483 { 2484 handle_t *handle; 2485 struct inode *inode; 2486 int err, credits, retries = 0; 2487 2488 err = dquot_initialize(dir); 2489 if (err) 2490 return err; 2491 2492 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2493 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2494 retry: 2495 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2496 NULL, EXT4_HT_DIR, credits); 2497 handle = ext4_journal_current_handle(); 2498 err = PTR_ERR(inode); 2499 if (!IS_ERR(inode)) { 2500 init_special_inode(inode, inode->i_mode, rdev); 2501 inode->i_op = &ext4_special_inode_operations; 2502 err = ext4_add_nondir(handle, dentry, inode); 2503 if (!err && IS_DIRSYNC(dir)) 2504 ext4_handle_sync(handle); 2505 } 2506 if (handle) 2507 ext4_journal_stop(handle); 2508 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2509 goto retry; 2510 return err; 2511 } 2512 2513 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 2514 { 2515 handle_t *handle; 2516 struct inode *inode; 2517 int err, retries = 0; 2518 2519 err = dquot_initialize(dir); 2520 if (err) 2521 return err; 2522 2523 retry: 2524 inode = ext4_new_inode_start_handle(dir, mode, 2525 NULL, 0, NULL, 2526 EXT4_HT_DIR, 2527 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 2528 4 + EXT4_XATTR_TRANS_BLOCKS); 2529 handle = ext4_journal_current_handle(); 2530 err = PTR_ERR(inode); 2531 if (!IS_ERR(inode)) { 2532 inode->i_op = &ext4_file_inode_operations; 2533 inode->i_fop = &ext4_file_operations; 2534 ext4_set_aops(inode); 2535 d_tmpfile(dentry, inode); 2536 err = ext4_orphan_add(handle, inode); 2537 if (err) 2538 goto err_unlock_inode; 2539 mark_inode_dirty(inode); 2540 unlock_new_inode(inode); 2541 } 2542 if (handle) 2543 ext4_journal_stop(handle); 2544 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2545 goto retry; 2546 return err; 2547 err_unlock_inode: 2548 ext4_journal_stop(handle); 2549 unlock_new_inode(inode); 2550 return err; 2551 } 2552 2553 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode, 2554 struct ext4_dir_entry_2 *de, 2555 int blocksize, int csum_size, 2556 unsigned int parent_ino, int dotdot_real_len) 2557 { 2558 de->inode = cpu_to_le32(inode->i_ino); 2559 de->name_len = 1; 2560 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), 2561 blocksize); 2562 strcpy(de->name, "."); 2563 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2564 2565 de = ext4_next_entry(de, blocksize); 2566 de->inode = cpu_to_le32(parent_ino); 2567 de->name_len = 2; 2568 if (!dotdot_real_len) 2569 de->rec_len = ext4_rec_len_to_disk(blocksize - 2570 (csum_size + EXT4_DIR_REC_LEN(1)), 2571 blocksize); 2572 else 2573 de->rec_len = ext4_rec_len_to_disk( 2574 EXT4_DIR_REC_LEN(de->name_len), blocksize); 2575 strcpy(de->name, ".."); 2576 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2577 2578 return ext4_next_entry(de, blocksize); 2579 } 2580 2581 static int ext4_init_new_dir(handle_t *handle, struct inode *dir, 2582 struct inode *inode) 2583 { 2584 struct buffer_head *dir_block = NULL; 2585 struct ext4_dir_entry_2 *de; 2586 struct ext4_dir_entry_tail *t; 2587 ext4_lblk_t block = 0; 2588 unsigned int blocksize = dir->i_sb->s_blocksize; 2589 int csum_size = 0; 2590 int err; 2591 2592 if (ext4_has_metadata_csum(dir->i_sb)) 2593 csum_size = sizeof(struct ext4_dir_entry_tail); 2594 2595 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { 2596 err = ext4_try_create_inline_dir(handle, dir, inode); 2597 if (err < 0 && err != -ENOSPC) 2598 goto out; 2599 if (!err) 2600 goto out; 2601 } 2602 2603 inode->i_size = 0; 2604 dir_block = ext4_append(handle, inode, &block); 2605 if (IS_ERR(dir_block)) 2606 return PTR_ERR(dir_block); 2607 de = (struct ext4_dir_entry_2 *)dir_block->b_data; 2608 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0); 2609 set_nlink(inode, 2); 2610 if (csum_size) { 2611 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize); 2612 initialize_dirent_tail(t, blocksize); 2613 } 2614 2615 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); 2616 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block); 2617 if (err) 2618 goto out; 2619 set_buffer_verified(dir_block); 2620 out: 2621 brelse(dir_block); 2622 return err; 2623 } 2624 2625 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2626 { 2627 handle_t *handle; 2628 struct inode *inode; 2629 int err, credits, retries = 0; 2630 2631 if (EXT4_DIR_LINK_MAX(dir)) 2632 return -EMLINK; 2633 2634 err = dquot_initialize(dir); 2635 if (err) 2636 return err; 2637 2638 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2639 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2640 retry: 2641 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode, 2642 &dentry->d_name, 2643 0, NULL, EXT4_HT_DIR, credits); 2644 handle = ext4_journal_current_handle(); 2645 err = PTR_ERR(inode); 2646 if (IS_ERR(inode)) 2647 goto out_stop; 2648 2649 inode->i_op = &ext4_dir_inode_operations; 2650 inode->i_fop = &ext4_dir_operations; 2651 err = ext4_init_new_dir(handle, dir, inode); 2652 if (err) 2653 goto out_clear_inode; 2654 err = ext4_mark_inode_dirty(handle, inode); 2655 if (!err) 2656 err = ext4_add_entry(handle, dentry, inode); 2657 if (err) { 2658 out_clear_inode: 2659 clear_nlink(inode); 2660 unlock_new_inode(inode); 2661 ext4_mark_inode_dirty(handle, inode); 2662 iput(inode); 2663 goto out_stop; 2664 } 2665 ext4_inc_count(handle, dir); 2666 ext4_update_dx_flag(dir); 2667 err = ext4_mark_inode_dirty(handle, dir); 2668 if (err) 2669 goto out_clear_inode; 2670 unlock_new_inode(inode); 2671 d_instantiate(dentry, inode); 2672 if (IS_DIRSYNC(dir)) 2673 ext4_handle_sync(handle); 2674 2675 out_stop: 2676 if (handle) 2677 ext4_journal_stop(handle); 2678 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2679 goto retry; 2680 return err; 2681 } 2682 2683 /* 2684 * routine to check that the specified directory is empty (for rmdir) 2685 */ 2686 bool ext4_empty_dir(struct inode *inode) 2687 { 2688 unsigned int offset; 2689 struct buffer_head *bh; 2690 struct ext4_dir_entry_2 *de, *de1; 2691 struct super_block *sb; 2692 2693 if (ext4_has_inline_data(inode)) { 2694 int has_inline_data = 1; 2695 int ret; 2696 2697 ret = empty_inline_dir(inode, &has_inline_data); 2698 if (has_inline_data) 2699 return ret; 2700 } 2701 2702 sb = inode->i_sb; 2703 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { 2704 EXT4_ERROR_INODE(inode, "invalid size"); 2705 return true; 2706 } 2707 bh = ext4_read_dirblock(inode, 0, EITHER); 2708 if (IS_ERR(bh)) 2709 return true; 2710 2711 de = (struct ext4_dir_entry_2 *) bh->b_data; 2712 de1 = ext4_next_entry(de, sb->s_blocksize); 2713 if (le32_to_cpu(de->inode) != inode->i_ino || 2714 le32_to_cpu(de1->inode) == 0 || 2715 strcmp(".", de->name) || strcmp("..", de1->name)) { 2716 ext4_warning_inode(inode, "directory missing '.' and/or '..'"); 2717 brelse(bh); 2718 return true; 2719 } 2720 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + 2721 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); 2722 de = ext4_next_entry(de1, sb->s_blocksize); 2723 while (offset < inode->i_size) { 2724 if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 2725 unsigned int lblock; 2726 brelse(bh); 2727 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); 2728 bh = ext4_read_dirblock(inode, lblock, EITHER); 2729 if (IS_ERR(bh)) 2730 return true; 2731 de = (struct ext4_dir_entry_2 *) bh->b_data; 2732 } 2733 if (ext4_check_dir_entry(inode, NULL, de, bh, 2734 bh->b_data, bh->b_size, offset)) { 2735 de = (struct ext4_dir_entry_2 *)(bh->b_data + 2736 sb->s_blocksize); 2737 offset = (offset | (sb->s_blocksize - 1)) + 1; 2738 continue; 2739 } 2740 if (le32_to_cpu(de->inode)) { 2741 brelse(bh); 2742 return false; 2743 } 2744 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2745 de = ext4_next_entry(de, sb->s_blocksize); 2746 } 2747 brelse(bh); 2748 return true; 2749 } 2750 2751 /* 2752 * ext4_orphan_add() links an unlinked or truncated inode into a list of 2753 * such inodes, starting at the superblock, in case we crash before the 2754 * file is closed/deleted, or in case the inode truncate spans multiple 2755 * transactions and the last transaction is not recovered after a crash. 2756 * 2757 * At filesystem recovery time, we walk this list deleting unlinked 2758 * inodes and truncating linked inodes in ext4_orphan_cleanup(). 2759 * 2760 * Orphan list manipulation functions must be called under i_mutex unless 2761 * we are just creating the inode or deleting it. 2762 */ 2763 int ext4_orphan_add(handle_t *handle, struct inode *inode) 2764 { 2765 struct super_block *sb = inode->i_sb; 2766 struct ext4_sb_info *sbi = EXT4_SB(sb); 2767 struct ext4_iloc iloc; 2768 int err = 0, rc; 2769 bool dirty = false; 2770 2771 if (!sbi->s_journal || is_bad_inode(inode)) 2772 return 0; 2773 2774 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2775 !inode_is_locked(inode)); 2776 /* 2777 * Exit early if inode already is on orphan list. This is a big speedup 2778 * since we don't have to contend on the global s_orphan_lock. 2779 */ 2780 if (!list_empty(&EXT4_I(inode)->i_orphan)) 2781 return 0; 2782 2783 /* 2784 * Orphan handling is only valid for files with data blocks 2785 * being truncated, or files being unlinked. Note that we either 2786 * hold i_mutex, or the inode can not be referenced from outside, 2787 * so i_nlink should not be bumped due to race 2788 */ 2789 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2790 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 2791 2792 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2793 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2794 if (err) 2795 goto out; 2796 2797 err = ext4_reserve_inode_write(handle, inode, &iloc); 2798 if (err) 2799 goto out; 2800 2801 mutex_lock(&sbi->s_orphan_lock); 2802 /* 2803 * Due to previous errors inode may be already a part of on-disk 2804 * orphan list. If so skip on-disk list modification. 2805 */ 2806 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) > 2807 (le32_to_cpu(sbi->s_es->s_inodes_count))) { 2808 /* Insert this inode at the head of the on-disk orphan list */ 2809 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan); 2810 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 2811 dirty = true; 2812 } 2813 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan); 2814 mutex_unlock(&sbi->s_orphan_lock); 2815 2816 if (dirty) { 2817 err = ext4_handle_dirty_super(handle, sb); 2818 rc = ext4_mark_iloc_dirty(handle, inode, &iloc); 2819 if (!err) 2820 err = rc; 2821 if (err) { 2822 /* 2823 * We have to remove inode from in-memory list if 2824 * addition to on disk orphan list failed. Stray orphan 2825 * list entries can cause panics at unmount time. 2826 */ 2827 mutex_lock(&sbi->s_orphan_lock); 2828 list_del_init(&EXT4_I(inode)->i_orphan); 2829 mutex_unlock(&sbi->s_orphan_lock); 2830 } 2831 } 2832 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 2833 jbd_debug(4, "orphan inode %lu will point to %d\n", 2834 inode->i_ino, NEXT_ORPHAN(inode)); 2835 out: 2836 ext4_std_error(sb, err); 2837 return err; 2838 } 2839 2840 /* 2841 * ext4_orphan_del() removes an unlinked or truncated inode from the list 2842 * of such inodes stored on disk, because it is finally being cleaned up. 2843 */ 2844 int ext4_orphan_del(handle_t *handle, struct inode *inode) 2845 { 2846 struct list_head *prev; 2847 struct ext4_inode_info *ei = EXT4_I(inode); 2848 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 2849 __u32 ino_next; 2850 struct ext4_iloc iloc; 2851 int err = 0; 2852 2853 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS)) 2854 return 0; 2855 2856 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2857 !inode_is_locked(inode)); 2858 /* Do this quick check before taking global s_orphan_lock. */ 2859 if (list_empty(&ei->i_orphan)) 2860 return 0; 2861 2862 if (handle) { 2863 /* Grab inode buffer early before taking global s_orphan_lock */ 2864 err = ext4_reserve_inode_write(handle, inode, &iloc); 2865 } 2866 2867 mutex_lock(&sbi->s_orphan_lock); 2868 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 2869 2870 prev = ei->i_orphan.prev; 2871 list_del_init(&ei->i_orphan); 2872 2873 /* If we're on an error path, we may not have a valid 2874 * transaction handle with which to update the orphan list on 2875 * disk, but we still need to remove the inode from the linked 2876 * list in memory. */ 2877 if (!handle || err) { 2878 mutex_unlock(&sbi->s_orphan_lock); 2879 goto out_err; 2880 } 2881 2882 ino_next = NEXT_ORPHAN(inode); 2883 if (prev == &sbi->s_orphan) { 2884 jbd_debug(4, "superblock will point to %u\n", ino_next); 2885 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2886 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2887 if (err) { 2888 mutex_unlock(&sbi->s_orphan_lock); 2889 goto out_brelse; 2890 } 2891 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 2892 mutex_unlock(&sbi->s_orphan_lock); 2893 err = ext4_handle_dirty_super(handle, inode->i_sb); 2894 } else { 2895 struct ext4_iloc iloc2; 2896 struct inode *i_prev = 2897 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; 2898 2899 jbd_debug(4, "orphan inode %lu will point to %u\n", 2900 i_prev->i_ino, ino_next); 2901 err = ext4_reserve_inode_write(handle, i_prev, &iloc2); 2902 if (err) { 2903 mutex_unlock(&sbi->s_orphan_lock); 2904 goto out_brelse; 2905 } 2906 NEXT_ORPHAN(i_prev) = ino_next; 2907 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); 2908 mutex_unlock(&sbi->s_orphan_lock); 2909 } 2910 if (err) 2911 goto out_brelse; 2912 NEXT_ORPHAN(inode) = 0; 2913 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 2914 out_err: 2915 ext4_std_error(inode->i_sb, err); 2916 return err; 2917 2918 out_brelse: 2919 brelse(iloc.bh); 2920 goto out_err; 2921 } 2922 2923 static int ext4_rmdir(struct inode *dir, struct dentry *dentry) 2924 { 2925 int retval; 2926 struct inode *inode; 2927 struct buffer_head *bh; 2928 struct ext4_dir_entry_2 *de; 2929 handle_t *handle = NULL; 2930 2931 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 2932 return -EIO; 2933 2934 /* Initialize quotas before so that eventual writes go in 2935 * separate transaction */ 2936 retval = dquot_initialize(dir); 2937 if (retval) 2938 return retval; 2939 retval = dquot_initialize(d_inode(dentry)); 2940 if (retval) 2941 return retval; 2942 2943 retval = -ENOENT; 2944 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 2945 if (IS_ERR(bh)) 2946 return PTR_ERR(bh); 2947 if (!bh) 2948 goto end_rmdir; 2949 2950 inode = d_inode(dentry); 2951 2952 retval = -EFSCORRUPTED; 2953 if (le32_to_cpu(de->inode) != inode->i_ino) 2954 goto end_rmdir; 2955 2956 retval = -ENOTEMPTY; 2957 if (!ext4_empty_dir(inode)) 2958 goto end_rmdir; 2959 2960 handle = ext4_journal_start(dir, EXT4_HT_DIR, 2961 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 2962 if (IS_ERR(handle)) { 2963 retval = PTR_ERR(handle); 2964 handle = NULL; 2965 goto end_rmdir; 2966 } 2967 2968 if (IS_DIRSYNC(dir)) 2969 ext4_handle_sync(handle); 2970 2971 retval = ext4_delete_entry(handle, dir, de, bh); 2972 if (retval) 2973 goto end_rmdir; 2974 if (!EXT4_DIR_LINK_EMPTY(inode)) 2975 ext4_warning_inode(inode, 2976 "empty directory '%.*s' has too many links (%u)", 2977 dentry->d_name.len, dentry->d_name.name, 2978 inode->i_nlink); 2979 inode->i_version++; 2980 clear_nlink(inode); 2981 /* There's no need to set i_disksize: the fact that i_nlink is 2982 * zero will ensure that the right thing happens during any 2983 * recovery. */ 2984 inode->i_size = 0; 2985 ext4_orphan_add(handle, inode); 2986 inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); 2987 ext4_mark_inode_dirty(handle, inode); 2988 ext4_dec_count(handle, dir); 2989 ext4_update_dx_flag(dir); 2990 ext4_mark_inode_dirty(handle, dir); 2991 2992 end_rmdir: 2993 brelse(bh); 2994 if (handle) 2995 ext4_journal_stop(handle); 2996 return retval; 2997 } 2998 2999 static int ext4_unlink(struct inode *dir, struct dentry *dentry) 3000 { 3001 int retval; 3002 struct inode *inode; 3003 struct buffer_head *bh; 3004 struct ext4_dir_entry_2 *de; 3005 handle_t *handle = NULL; 3006 3007 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3008 return -EIO; 3009 3010 trace_ext4_unlink_enter(dir, dentry); 3011 /* Initialize quotas before so that eventual writes go 3012 * in separate transaction */ 3013 retval = dquot_initialize(dir); 3014 if (retval) 3015 return retval; 3016 retval = dquot_initialize(d_inode(dentry)); 3017 if (retval) 3018 return retval; 3019 3020 retval = -ENOENT; 3021 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 3022 if (IS_ERR(bh)) 3023 return PTR_ERR(bh); 3024 if (!bh) 3025 goto end_unlink; 3026 3027 inode = d_inode(dentry); 3028 3029 retval = -EFSCORRUPTED; 3030 if (le32_to_cpu(de->inode) != inode->i_ino) 3031 goto end_unlink; 3032 3033 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3034 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 3035 if (IS_ERR(handle)) { 3036 retval = PTR_ERR(handle); 3037 handle = NULL; 3038 goto end_unlink; 3039 } 3040 3041 if (IS_DIRSYNC(dir)) 3042 ext4_handle_sync(handle); 3043 3044 if (inode->i_nlink == 0) { 3045 ext4_warning_inode(inode, "Deleting file '%.*s' with no links", 3046 dentry->d_name.len, dentry->d_name.name); 3047 set_nlink(inode, 1); 3048 } 3049 retval = ext4_delete_entry(handle, dir, de, bh); 3050 if (retval) 3051 goto end_unlink; 3052 dir->i_ctime = dir->i_mtime = current_time(dir); 3053 ext4_update_dx_flag(dir); 3054 ext4_mark_inode_dirty(handle, dir); 3055 drop_nlink(inode); 3056 if (!inode->i_nlink) 3057 ext4_orphan_add(handle, inode); 3058 inode->i_ctime = current_time(inode); 3059 ext4_mark_inode_dirty(handle, inode); 3060 3061 end_unlink: 3062 brelse(bh); 3063 if (handle) 3064 ext4_journal_stop(handle); 3065 trace_ext4_unlink_exit(dentry, retval); 3066 return retval; 3067 } 3068 3069 static int ext4_symlink(struct inode *dir, 3070 struct dentry *dentry, const char *symname) 3071 { 3072 handle_t *handle; 3073 struct inode *inode; 3074 int err, len = strlen(symname); 3075 int credits; 3076 bool encryption_required; 3077 struct fscrypt_str disk_link; 3078 struct fscrypt_symlink_data *sd = NULL; 3079 3080 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3081 return -EIO; 3082 3083 disk_link.len = len + 1; 3084 disk_link.name = (char *) symname; 3085 3086 encryption_required = (ext4_encrypted_inode(dir) || 3087 DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb))); 3088 if (encryption_required) { 3089 err = fscrypt_get_encryption_info(dir); 3090 if (err) 3091 return err; 3092 if (!fscrypt_has_encryption_key(dir)) 3093 return -ENOKEY; 3094 disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + 3095 sizeof(struct fscrypt_symlink_data)); 3096 sd = kzalloc(disk_link.len, GFP_KERNEL); 3097 if (!sd) 3098 return -ENOMEM; 3099 } 3100 3101 if (disk_link.len > dir->i_sb->s_blocksize) { 3102 err = -ENAMETOOLONG; 3103 goto err_free_sd; 3104 } 3105 3106 err = dquot_initialize(dir); 3107 if (err) 3108 goto err_free_sd; 3109 3110 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3111 /* 3112 * For non-fast symlinks, we just allocate inode and put it on 3113 * orphan list in the first transaction => we need bitmap, 3114 * group descriptor, sb, inode block, quota blocks, and 3115 * possibly selinux xattr blocks. 3116 */ 3117 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 3118 EXT4_XATTR_TRANS_BLOCKS; 3119 } else { 3120 /* 3121 * Fast symlink. We have to add entry to directory 3122 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), 3123 * allocate new inode (bitmap, group descriptor, inode block, 3124 * quota blocks, sb is already counted in previous macros). 3125 */ 3126 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3127 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3; 3128 } 3129 3130 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO, 3131 &dentry->d_name, 0, NULL, 3132 EXT4_HT_DIR, credits); 3133 handle = ext4_journal_current_handle(); 3134 if (IS_ERR(inode)) { 3135 if (handle) 3136 ext4_journal_stop(handle); 3137 err = PTR_ERR(inode); 3138 goto err_free_sd; 3139 } 3140 3141 if (encryption_required) { 3142 struct qstr istr; 3143 struct fscrypt_str ostr = 3144 FSTR_INIT(sd->encrypted_path, disk_link.len); 3145 3146 istr.name = (const unsigned char *) symname; 3147 istr.len = len; 3148 err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); 3149 if (err) 3150 goto err_drop_inode; 3151 sd->len = cpu_to_le16(ostr.len); 3152 disk_link.name = (char *) sd; 3153 inode->i_op = &ext4_encrypted_symlink_inode_operations; 3154 } 3155 3156 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3157 if (!encryption_required) 3158 inode->i_op = &ext4_symlink_inode_operations; 3159 inode_nohighmem(inode); 3160 ext4_set_aops(inode); 3161 /* 3162 * We cannot call page_symlink() with transaction started 3163 * because it calls into ext4_write_begin() which can wait 3164 * for transaction commit if we are running out of space 3165 * and thus we deadlock. So we have to stop transaction now 3166 * and restart it when symlink contents is written. 3167 * 3168 * To keep fs consistent in case of crash, we have to put inode 3169 * to orphan list in the mean time. 3170 */ 3171 drop_nlink(inode); 3172 err = ext4_orphan_add(handle, inode); 3173 ext4_journal_stop(handle); 3174 handle = NULL; 3175 if (err) 3176 goto err_drop_inode; 3177 err = __page_symlink(inode, disk_link.name, disk_link.len, 1); 3178 if (err) 3179 goto err_drop_inode; 3180 /* 3181 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS 3182 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified 3183 */ 3184 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3185 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3186 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); 3187 if (IS_ERR(handle)) { 3188 err = PTR_ERR(handle); 3189 handle = NULL; 3190 goto err_drop_inode; 3191 } 3192 set_nlink(inode, 1); 3193 err = ext4_orphan_del(handle, inode); 3194 if (err) 3195 goto err_drop_inode; 3196 } else { 3197 /* clear the extent format for fast symlink */ 3198 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); 3199 if (!encryption_required) { 3200 inode->i_op = &ext4_fast_symlink_inode_operations; 3201 inode->i_link = (char *)&EXT4_I(inode)->i_data; 3202 } 3203 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name, 3204 disk_link.len); 3205 inode->i_size = disk_link.len - 1; 3206 } 3207 EXT4_I(inode)->i_disksize = inode->i_size; 3208 err = ext4_add_nondir(handle, dentry, inode); 3209 if (!err && IS_DIRSYNC(dir)) 3210 ext4_handle_sync(handle); 3211 3212 if (handle) 3213 ext4_journal_stop(handle); 3214 kfree(sd); 3215 return err; 3216 err_drop_inode: 3217 if (handle) 3218 ext4_journal_stop(handle); 3219 clear_nlink(inode); 3220 unlock_new_inode(inode); 3221 iput(inode); 3222 err_free_sd: 3223 kfree(sd); 3224 return err; 3225 } 3226 3227 static int ext4_link(struct dentry *old_dentry, 3228 struct inode *dir, struct dentry *dentry) 3229 { 3230 handle_t *handle; 3231 struct inode *inode = d_inode(old_dentry); 3232 int err, retries = 0; 3233 3234 if (inode->i_nlink >= EXT4_LINK_MAX) 3235 return -EMLINK; 3236 if (ext4_encrypted_inode(dir) && 3237 !fscrypt_has_permitted_context(dir, inode)) 3238 return -EPERM; 3239 3240 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) && 3241 (!projid_eq(EXT4_I(dir)->i_projid, 3242 EXT4_I(old_dentry->d_inode)->i_projid))) 3243 return -EXDEV; 3244 3245 err = dquot_initialize(dir); 3246 if (err) 3247 return err; 3248 3249 retry: 3250 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3251 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3252 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1); 3253 if (IS_ERR(handle)) 3254 return PTR_ERR(handle); 3255 3256 if (IS_DIRSYNC(dir)) 3257 ext4_handle_sync(handle); 3258 3259 inode->i_ctime = current_time(inode); 3260 ext4_inc_count(handle, inode); 3261 ihold(inode); 3262 3263 err = ext4_add_entry(handle, dentry, inode); 3264 if (!err) { 3265 ext4_mark_inode_dirty(handle, inode); 3266 /* this can happen only for tmpfile being 3267 * linked the first time 3268 */ 3269 if (inode->i_nlink == 1) 3270 ext4_orphan_del(handle, inode); 3271 d_instantiate(dentry, inode); 3272 } else { 3273 drop_nlink(inode); 3274 iput(inode); 3275 } 3276 ext4_journal_stop(handle); 3277 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 3278 goto retry; 3279 return err; 3280 } 3281 3282 3283 /* 3284 * Try to find buffer head where contains the parent block. 3285 * It should be the inode block if it is inlined or the 1st block 3286 * if it is a normal dir. 3287 */ 3288 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, 3289 struct inode *inode, 3290 int *retval, 3291 struct ext4_dir_entry_2 **parent_de, 3292 int *inlined) 3293 { 3294 struct buffer_head *bh; 3295 3296 if (!ext4_has_inline_data(inode)) { 3297 bh = ext4_read_dirblock(inode, 0, EITHER); 3298 if (IS_ERR(bh)) { 3299 *retval = PTR_ERR(bh); 3300 return NULL; 3301 } 3302 *parent_de = ext4_next_entry( 3303 (struct ext4_dir_entry_2 *)bh->b_data, 3304 inode->i_sb->s_blocksize); 3305 return bh; 3306 } 3307 3308 *inlined = 1; 3309 return ext4_get_first_inline_block(inode, parent_de, retval); 3310 } 3311 3312 struct ext4_renament { 3313 struct inode *dir; 3314 struct dentry *dentry; 3315 struct inode *inode; 3316 bool is_dir; 3317 int dir_nlink_delta; 3318 3319 /* entry for "dentry" */ 3320 struct buffer_head *bh; 3321 struct ext4_dir_entry_2 *de; 3322 int inlined; 3323 3324 /* entry for ".." in inode if it's a directory */ 3325 struct buffer_head *dir_bh; 3326 struct ext4_dir_entry_2 *parent_de; 3327 int dir_inlined; 3328 }; 3329 3330 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) 3331 { 3332 int retval; 3333 3334 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, 3335 &retval, &ent->parent_de, 3336 &ent->dir_inlined); 3337 if (!ent->dir_bh) 3338 return retval; 3339 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) 3340 return -EFSCORRUPTED; 3341 BUFFER_TRACE(ent->dir_bh, "get_write_access"); 3342 return ext4_journal_get_write_access(handle, ent->dir_bh); 3343 } 3344 3345 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, 3346 unsigned dir_ino) 3347 { 3348 int retval; 3349 3350 ent->parent_de->inode = cpu_to_le32(dir_ino); 3351 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); 3352 if (!ent->dir_inlined) { 3353 if (is_dx(ent->inode)) { 3354 retval = ext4_handle_dirty_dx_node(handle, 3355 ent->inode, 3356 ent->dir_bh); 3357 } else { 3358 retval = ext4_handle_dirty_dirent_node(handle, 3359 ent->inode, 3360 ent->dir_bh); 3361 } 3362 } else { 3363 retval = ext4_mark_inode_dirty(handle, ent->inode); 3364 } 3365 if (retval) { 3366 ext4_std_error(ent->dir->i_sb, retval); 3367 return retval; 3368 } 3369 return 0; 3370 } 3371 3372 static int ext4_setent(handle_t *handle, struct ext4_renament *ent, 3373 unsigned ino, unsigned file_type) 3374 { 3375 int retval; 3376 3377 BUFFER_TRACE(ent->bh, "get write access"); 3378 retval = ext4_journal_get_write_access(handle, ent->bh); 3379 if (retval) 3380 return retval; 3381 ent->de->inode = cpu_to_le32(ino); 3382 if (ext4_has_feature_filetype(ent->dir->i_sb)) 3383 ent->de->file_type = file_type; 3384 ent->dir->i_version++; 3385 ent->dir->i_ctime = ent->dir->i_mtime = 3386 current_time(ent->dir); 3387 ext4_mark_inode_dirty(handle, ent->dir); 3388 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); 3389 if (!ent->inlined) { 3390 retval = ext4_handle_dirty_dirent_node(handle, 3391 ent->dir, ent->bh); 3392 if (unlikely(retval)) { 3393 ext4_std_error(ent->dir->i_sb, retval); 3394 return retval; 3395 } 3396 } 3397 brelse(ent->bh); 3398 ent->bh = NULL; 3399 3400 return 0; 3401 } 3402 3403 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, 3404 const struct qstr *d_name) 3405 { 3406 int retval = -ENOENT; 3407 struct buffer_head *bh; 3408 struct ext4_dir_entry_2 *de; 3409 3410 bh = ext4_find_entry(dir, d_name, &de, NULL); 3411 if (IS_ERR(bh)) 3412 return PTR_ERR(bh); 3413 if (bh) { 3414 retval = ext4_delete_entry(handle, dir, de, bh); 3415 brelse(bh); 3416 } 3417 return retval; 3418 } 3419 3420 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent, 3421 int force_reread) 3422 { 3423 int retval; 3424 /* 3425 * ent->de could have moved from under us during htree split, so make 3426 * sure that we are deleting the right entry. We might also be pointing 3427 * to a stale entry in the unused part of ent->bh so just checking inum 3428 * and the name isn't enough. 3429 */ 3430 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || 3431 ent->de->name_len != ent->dentry->d_name.len || 3432 strncmp(ent->de->name, ent->dentry->d_name.name, 3433 ent->de->name_len) || 3434 force_reread) { 3435 retval = ext4_find_delete_entry(handle, ent->dir, 3436 &ent->dentry->d_name); 3437 } else { 3438 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); 3439 if (retval == -ENOENT) { 3440 retval = ext4_find_delete_entry(handle, ent->dir, 3441 &ent->dentry->d_name); 3442 } 3443 } 3444 3445 if (retval) { 3446 ext4_warning_inode(ent->dir, 3447 "Deleting old file: nlink %d, error=%d", 3448 ent->dir->i_nlink, retval); 3449 } 3450 } 3451 3452 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) 3453 { 3454 if (ent->dir_nlink_delta) { 3455 if (ent->dir_nlink_delta == -1) 3456 ext4_dec_count(handle, ent->dir); 3457 else 3458 ext4_inc_count(handle, ent->dir); 3459 ext4_mark_inode_dirty(handle, ent->dir); 3460 } 3461 } 3462 3463 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, 3464 int credits, handle_t **h) 3465 { 3466 struct inode *wh; 3467 handle_t *handle; 3468 int retries = 0; 3469 3470 /* 3471 * for inode block, sb block, group summaries, 3472 * and inode bitmap 3473 */ 3474 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + 3475 EXT4_XATTR_TRANS_BLOCKS + 4); 3476 retry: 3477 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, 3478 &ent->dentry->d_name, 0, NULL, 3479 EXT4_HT_DIR, credits); 3480 3481 handle = ext4_journal_current_handle(); 3482 if (IS_ERR(wh)) { 3483 if (handle) 3484 ext4_journal_stop(handle); 3485 if (PTR_ERR(wh) == -ENOSPC && 3486 ext4_should_retry_alloc(ent->dir->i_sb, &retries)) 3487 goto retry; 3488 } else { 3489 *h = handle; 3490 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); 3491 wh->i_op = &ext4_special_inode_operations; 3492 } 3493 return wh; 3494 } 3495 3496 /* 3497 * Anybody can rename anything with this: the permission checks are left to the 3498 * higher-level routines. 3499 * 3500 * n.b. old_{dentry,inode) refers to the source dentry/inode 3501 * while new_{dentry,inode) refers to the destination dentry/inode 3502 * This comes from rename(const char *oldpath, const char *newpath) 3503 */ 3504 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, 3505 struct inode *new_dir, struct dentry *new_dentry, 3506 unsigned int flags) 3507 { 3508 handle_t *handle = NULL; 3509 struct ext4_renament old = { 3510 .dir = old_dir, 3511 .dentry = old_dentry, 3512 .inode = d_inode(old_dentry), 3513 }; 3514 struct ext4_renament new = { 3515 .dir = new_dir, 3516 .dentry = new_dentry, 3517 .inode = d_inode(new_dentry), 3518 }; 3519 int force_reread; 3520 int retval; 3521 struct inode *whiteout = NULL; 3522 int credits; 3523 u8 old_file_type; 3524 3525 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && 3526 (!projid_eq(EXT4_I(new_dir)->i_projid, 3527 EXT4_I(old_dentry->d_inode)->i_projid))) 3528 return -EXDEV; 3529 3530 if ((ext4_encrypted_inode(old_dir) && 3531 !fscrypt_has_encryption_key(old_dir)) || 3532 (ext4_encrypted_inode(new_dir) && 3533 !fscrypt_has_encryption_key(new_dir))) 3534 return -ENOKEY; 3535 3536 retval = dquot_initialize(old.dir); 3537 if (retval) 3538 return retval; 3539 retval = dquot_initialize(new.dir); 3540 if (retval) 3541 return retval; 3542 3543 /* Initialize quotas before so that eventual writes go 3544 * in separate transaction */ 3545 if (new.inode) { 3546 retval = dquot_initialize(new.inode); 3547 if (retval) 3548 return retval; 3549 } 3550 3551 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); 3552 if (IS_ERR(old.bh)) 3553 return PTR_ERR(old.bh); 3554 /* 3555 * Check for inode number is _not_ due to possible IO errors. 3556 * We might rmdir the source, keep it as pwd of some process 3557 * and merrily kill the link to whatever was created under the 3558 * same name. Goodbye sticky bit ;-< 3559 */ 3560 retval = -ENOENT; 3561 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3562 goto end_rename; 3563 3564 if ((old.dir != new.dir) && 3565 ext4_encrypted_inode(new.dir) && 3566 !fscrypt_has_permitted_context(new.dir, old.inode)) { 3567 retval = -EPERM; 3568 goto end_rename; 3569 } 3570 3571 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3572 &new.de, &new.inlined); 3573 if (IS_ERR(new.bh)) { 3574 retval = PTR_ERR(new.bh); 3575 new.bh = NULL; 3576 goto end_rename; 3577 } 3578 if (new.bh) { 3579 if (!new.inode) { 3580 brelse(new.bh); 3581 new.bh = NULL; 3582 } 3583 } 3584 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) 3585 ext4_alloc_da_blocks(old.inode); 3586 3587 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3588 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); 3589 if (!(flags & RENAME_WHITEOUT)) { 3590 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); 3591 if (IS_ERR(handle)) { 3592 retval = PTR_ERR(handle); 3593 handle = NULL; 3594 goto end_rename; 3595 } 3596 } else { 3597 whiteout = ext4_whiteout_for_rename(&old, credits, &handle); 3598 if (IS_ERR(whiteout)) { 3599 retval = PTR_ERR(whiteout); 3600 whiteout = NULL; 3601 goto end_rename; 3602 } 3603 } 3604 3605 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3606 ext4_handle_sync(handle); 3607 3608 if (S_ISDIR(old.inode->i_mode)) { 3609 if (new.inode) { 3610 retval = -ENOTEMPTY; 3611 if (!ext4_empty_dir(new.inode)) 3612 goto end_rename; 3613 } else { 3614 retval = -EMLINK; 3615 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) 3616 goto end_rename; 3617 } 3618 retval = ext4_rename_dir_prepare(handle, &old); 3619 if (retval) 3620 goto end_rename; 3621 } 3622 /* 3623 * If we're renaming a file within an inline_data dir and adding or 3624 * setting the new dirent causes a conversion from inline_data to 3625 * extents/blockmap, we need to force the dirent delete code to 3626 * re-read the directory, or else we end up trying to delete a dirent 3627 * from what is now the extent tree root (or a block map). 3628 */ 3629 force_reread = (new.dir->i_ino == old.dir->i_ino && 3630 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); 3631 3632 old_file_type = old.de->file_type; 3633 if (whiteout) { 3634 /* 3635 * Do this before adding a new entry, so the old entry is sure 3636 * to be still pointing to the valid old entry. 3637 */ 3638 retval = ext4_setent(handle, &old, whiteout->i_ino, 3639 EXT4_FT_CHRDEV); 3640 if (retval) 3641 goto end_rename; 3642 ext4_mark_inode_dirty(handle, whiteout); 3643 } 3644 if (!new.bh) { 3645 retval = ext4_add_entry(handle, new.dentry, old.inode); 3646 if (retval) 3647 goto end_rename; 3648 } else { 3649 retval = ext4_setent(handle, &new, 3650 old.inode->i_ino, old_file_type); 3651 if (retval) 3652 goto end_rename; 3653 } 3654 if (force_reread) 3655 force_reread = !ext4_test_inode_flag(new.dir, 3656 EXT4_INODE_INLINE_DATA); 3657 3658 /* 3659 * Like most other Unix systems, set the ctime for inodes on a 3660 * rename. 3661 */ 3662 old.inode->i_ctime = current_time(old.inode); 3663 ext4_mark_inode_dirty(handle, old.inode); 3664 3665 if (!whiteout) { 3666 /* 3667 * ok, that's it 3668 */ 3669 ext4_rename_delete(handle, &old, force_reread); 3670 } 3671 3672 if (new.inode) { 3673 ext4_dec_count(handle, new.inode); 3674 new.inode->i_ctime = current_time(new.inode); 3675 } 3676 old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir); 3677 ext4_update_dx_flag(old.dir); 3678 if (old.dir_bh) { 3679 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3680 if (retval) 3681 goto end_rename; 3682 3683 ext4_dec_count(handle, old.dir); 3684 if (new.inode) { 3685 /* checked ext4_empty_dir above, can't have another 3686 * parent, ext4_dec_count() won't work for many-linked 3687 * dirs */ 3688 clear_nlink(new.inode); 3689 } else { 3690 ext4_inc_count(handle, new.dir); 3691 ext4_update_dx_flag(new.dir); 3692 ext4_mark_inode_dirty(handle, new.dir); 3693 } 3694 } 3695 ext4_mark_inode_dirty(handle, old.dir); 3696 if (new.inode) { 3697 ext4_mark_inode_dirty(handle, new.inode); 3698 if (!new.inode->i_nlink) 3699 ext4_orphan_add(handle, new.inode); 3700 } 3701 retval = 0; 3702 3703 end_rename: 3704 brelse(old.dir_bh); 3705 brelse(old.bh); 3706 brelse(new.bh); 3707 if (whiteout) { 3708 if (retval) 3709 drop_nlink(whiteout); 3710 unlock_new_inode(whiteout); 3711 iput(whiteout); 3712 } 3713 if (handle) 3714 ext4_journal_stop(handle); 3715 return retval; 3716 } 3717 3718 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, 3719 struct inode *new_dir, struct dentry *new_dentry) 3720 { 3721 handle_t *handle = NULL; 3722 struct ext4_renament old = { 3723 .dir = old_dir, 3724 .dentry = old_dentry, 3725 .inode = d_inode(old_dentry), 3726 }; 3727 struct ext4_renament new = { 3728 .dir = new_dir, 3729 .dentry = new_dentry, 3730 .inode = d_inode(new_dentry), 3731 }; 3732 u8 new_file_type; 3733 int retval; 3734 struct timespec ctime; 3735 3736 if ((ext4_encrypted_inode(old_dir) && 3737 !fscrypt_has_encryption_key(old_dir)) || 3738 (ext4_encrypted_inode(new_dir) && 3739 !fscrypt_has_encryption_key(new_dir))) 3740 return -ENOKEY; 3741 3742 if ((ext4_encrypted_inode(old_dir) || 3743 ext4_encrypted_inode(new_dir)) && 3744 (old_dir != new_dir) && 3745 (!fscrypt_has_permitted_context(new_dir, old.inode) || 3746 !fscrypt_has_permitted_context(old_dir, new.inode))) 3747 return -EPERM; 3748 3749 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) && 3750 !projid_eq(EXT4_I(new_dir)->i_projid, 3751 EXT4_I(old_dentry->d_inode)->i_projid)) || 3752 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) && 3753 !projid_eq(EXT4_I(old_dir)->i_projid, 3754 EXT4_I(new_dentry->d_inode)->i_projid))) 3755 return -EXDEV; 3756 3757 retval = dquot_initialize(old.dir); 3758 if (retval) 3759 return retval; 3760 retval = dquot_initialize(new.dir); 3761 if (retval) 3762 return retval; 3763 3764 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, 3765 &old.de, &old.inlined); 3766 if (IS_ERR(old.bh)) 3767 return PTR_ERR(old.bh); 3768 /* 3769 * Check for inode number is _not_ due to possible IO errors. 3770 * We might rmdir the source, keep it as pwd of some process 3771 * and merrily kill the link to whatever was created under the 3772 * same name. Goodbye sticky bit ;-< 3773 */ 3774 retval = -ENOENT; 3775 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3776 goto end_rename; 3777 3778 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3779 &new.de, &new.inlined); 3780 if (IS_ERR(new.bh)) { 3781 retval = PTR_ERR(new.bh); 3782 new.bh = NULL; 3783 goto end_rename; 3784 } 3785 3786 /* RENAME_EXCHANGE case: old *and* new must both exist */ 3787 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) 3788 goto end_rename; 3789 3790 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, 3791 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3792 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); 3793 if (IS_ERR(handle)) { 3794 retval = PTR_ERR(handle); 3795 handle = NULL; 3796 goto end_rename; 3797 } 3798 3799 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3800 ext4_handle_sync(handle); 3801 3802 if (S_ISDIR(old.inode->i_mode)) { 3803 old.is_dir = true; 3804 retval = ext4_rename_dir_prepare(handle, &old); 3805 if (retval) 3806 goto end_rename; 3807 } 3808 if (S_ISDIR(new.inode->i_mode)) { 3809 new.is_dir = true; 3810 retval = ext4_rename_dir_prepare(handle, &new); 3811 if (retval) 3812 goto end_rename; 3813 } 3814 3815 /* 3816 * Other than the special case of overwriting a directory, parents' 3817 * nlink only needs to be modified if this is a cross directory rename. 3818 */ 3819 if (old.dir != new.dir && old.is_dir != new.is_dir) { 3820 old.dir_nlink_delta = old.is_dir ? -1 : 1; 3821 new.dir_nlink_delta = -old.dir_nlink_delta; 3822 retval = -EMLINK; 3823 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || 3824 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) 3825 goto end_rename; 3826 } 3827 3828 new_file_type = new.de->file_type; 3829 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); 3830 if (retval) 3831 goto end_rename; 3832 3833 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); 3834 if (retval) 3835 goto end_rename; 3836 3837 /* 3838 * Like most other Unix systems, set the ctime for inodes on a 3839 * rename. 3840 */ 3841 ctime = current_time(old.inode); 3842 old.inode->i_ctime = ctime; 3843 new.inode->i_ctime = ctime; 3844 ext4_mark_inode_dirty(handle, old.inode); 3845 ext4_mark_inode_dirty(handle, new.inode); 3846 3847 if (old.dir_bh) { 3848 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3849 if (retval) 3850 goto end_rename; 3851 } 3852 if (new.dir_bh) { 3853 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); 3854 if (retval) 3855 goto end_rename; 3856 } 3857 ext4_update_dir_count(handle, &old); 3858 ext4_update_dir_count(handle, &new); 3859 retval = 0; 3860 3861 end_rename: 3862 brelse(old.dir_bh); 3863 brelse(new.dir_bh); 3864 brelse(old.bh); 3865 brelse(new.bh); 3866 if (handle) 3867 ext4_journal_stop(handle); 3868 return retval; 3869 } 3870 3871 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, 3872 struct inode *new_dir, struct dentry *new_dentry, 3873 unsigned int flags) 3874 { 3875 if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb)))) 3876 return -EIO; 3877 3878 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 3879 return -EINVAL; 3880 3881 if (flags & RENAME_EXCHANGE) { 3882 return ext4_cross_rename(old_dir, old_dentry, 3883 new_dir, new_dentry); 3884 } 3885 3886 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 3887 } 3888 3889 /* 3890 * directories can handle most operations... 3891 */ 3892 const struct inode_operations ext4_dir_inode_operations = { 3893 .create = ext4_create, 3894 .lookup = ext4_lookup, 3895 .link = ext4_link, 3896 .unlink = ext4_unlink, 3897 .symlink = ext4_symlink, 3898 .mkdir = ext4_mkdir, 3899 .rmdir = ext4_rmdir, 3900 .mknod = ext4_mknod, 3901 .tmpfile = ext4_tmpfile, 3902 .rename = ext4_rename2, 3903 .setattr = ext4_setattr, 3904 .getattr = ext4_getattr, 3905 .listxattr = ext4_listxattr, 3906 .get_acl = ext4_get_acl, 3907 .set_acl = ext4_set_acl, 3908 .fiemap = ext4_fiemap, 3909 }; 3910 3911 const struct inode_operations ext4_special_inode_operations = { 3912 .setattr = ext4_setattr, 3913 .getattr = ext4_getattr, 3914 .listxattr = ext4_listxattr, 3915 .get_acl = ext4_get_acl, 3916 .set_acl = ext4_set_acl, 3917 }; 3918