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; 1346 const u8 *name = d_name->name; 1347 size_t ra_max = 0; /* Number of bh's in the readahead 1348 buffer, bh_use[] */ 1349 size_t ra_ptr = 0; /* Current index into readahead 1350 buffer */ 1351 ext4_lblk_t nblocks; 1352 int i, namelen, retval; 1353 struct ext4_filename fname; 1354 1355 *res_dir = NULL; 1356 sb = dir->i_sb; 1357 namelen = d_name->len; 1358 if (namelen > EXT4_NAME_LEN) 1359 return NULL; 1360 1361 retval = ext4_fname_setup_filename(dir, d_name, 1, &fname); 1362 if (retval == -ENOENT) 1363 return NULL; 1364 if (retval) 1365 return ERR_PTR(retval); 1366 1367 if (ext4_has_inline_data(dir)) { 1368 int has_inline_data = 1; 1369 ret = ext4_find_inline_entry(dir, &fname, res_dir, 1370 &has_inline_data); 1371 if (has_inline_data) { 1372 if (inlined) 1373 *inlined = 1; 1374 goto cleanup_and_exit; 1375 } 1376 } 1377 1378 if ((namelen <= 2) && (name[0] == '.') && 1379 (name[1] == '.' || name[1] == '\0')) { 1380 /* 1381 * "." or ".." will only be in the first block 1382 * NFS may look up ".."; "." should be handled by the VFS 1383 */ 1384 block = start = 0; 1385 nblocks = 1; 1386 goto restart; 1387 } 1388 if (is_dx(dir)) { 1389 ret = ext4_dx_find_entry(dir, &fname, res_dir); 1390 /* 1391 * On success, or if the error was file not found, 1392 * return. Otherwise, fall back to doing a search the 1393 * old fashioned way. 1394 */ 1395 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) 1396 goto cleanup_and_exit; 1397 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " 1398 "falling back\n")); 1399 } 1400 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1401 start = EXT4_I(dir)->i_dir_start_lookup; 1402 if (start >= nblocks) 1403 start = 0; 1404 block = start; 1405 restart: 1406 do { 1407 /* 1408 * We deal with the read-ahead logic here. 1409 */ 1410 if (ra_ptr >= ra_max) { 1411 /* Refill the readahead buffer */ 1412 ra_ptr = 0; 1413 if (block < start) 1414 ra_max = start - block; 1415 else 1416 ra_max = nblocks - block; 1417 ra_max = min(ra_max, ARRAY_SIZE(bh_use)); 1418 retval = ext4_bread_batch(dir, block, ra_max, 1419 false /* wait */, bh_use); 1420 if (retval) { 1421 ret = ERR_PTR(retval); 1422 ra_max = 0; 1423 goto cleanup_and_exit; 1424 } 1425 } 1426 if ((bh = bh_use[ra_ptr++]) == NULL) 1427 goto next; 1428 wait_on_buffer(bh); 1429 if (!buffer_uptodate(bh)) { 1430 EXT4_ERROR_INODE(dir, "reading directory lblock %lu", 1431 (unsigned long) block); 1432 brelse(bh); 1433 ret = ERR_PTR(-EIO); 1434 goto cleanup_and_exit; 1435 } 1436 if (!buffer_verified(bh) && 1437 !is_dx_internal_node(dir, block, 1438 (struct ext4_dir_entry *)bh->b_data) && 1439 !ext4_dirent_csum_verify(dir, 1440 (struct ext4_dir_entry *)bh->b_data)) { 1441 EXT4_ERROR_INODE(dir, "checksumming directory " 1442 "block %lu", (unsigned long)block); 1443 brelse(bh); 1444 ret = ERR_PTR(-EFSBADCRC); 1445 goto cleanup_and_exit; 1446 } 1447 set_buffer_verified(bh); 1448 i = search_dirblock(bh, dir, &fname, 1449 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); 1450 if (i == 1) { 1451 EXT4_I(dir)->i_dir_start_lookup = block; 1452 ret = bh; 1453 goto cleanup_and_exit; 1454 } else { 1455 brelse(bh); 1456 if (i < 0) 1457 goto cleanup_and_exit; 1458 } 1459 next: 1460 if (++block >= nblocks) 1461 block = 0; 1462 } while (block != start); 1463 1464 /* 1465 * If the directory has grown while we were searching, then 1466 * search the last part of the directory before giving up. 1467 */ 1468 block = nblocks; 1469 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1470 if (block < nblocks) { 1471 start = 0; 1472 goto restart; 1473 } 1474 1475 cleanup_and_exit: 1476 /* Clean up the read-ahead blocks */ 1477 for (; ra_ptr < ra_max; ra_ptr++) 1478 brelse(bh_use[ra_ptr]); 1479 ext4_fname_free_filename(&fname); 1480 return ret; 1481 } 1482 1483 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 1484 struct ext4_filename *fname, 1485 struct ext4_dir_entry_2 **res_dir) 1486 { 1487 struct super_block * sb = dir->i_sb; 1488 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1489 struct buffer_head *bh; 1490 ext4_lblk_t block; 1491 int retval; 1492 1493 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1494 *res_dir = NULL; 1495 #endif 1496 frame = dx_probe(fname, dir, NULL, frames); 1497 if (IS_ERR(frame)) 1498 return (struct buffer_head *) frame; 1499 do { 1500 block = dx_get_block(frame->at); 1501 bh = ext4_read_dirblock(dir, block, DIRENT); 1502 if (IS_ERR(bh)) 1503 goto errout; 1504 1505 retval = search_dirblock(bh, dir, fname, 1506 block << EXT4_BLOCK_SIZE_BITS(sb), 1507 res_dir); 1508 if (retval == 1) 1509 goto success; 1510 brelse(bh); 1511 if (retval == -1) { 1512 bh = ERR_PTR(ERR_BAD_DX_DIR); 1513 goto errout; 1514 } 1515 1516 /* Check to see if we should continue to search */ 1517 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame, 1518 frames, NULL); 1519 if (retval < 0) { 1520 ext4_warning_inode(dir, 1521 "error %d reading directory index block", 1522 retval); 1523 bh = ERR_PTR(retval); 1524 goto errout; 1525 } 1526 } while (retval == 1); 1527 1528 bh = NULL; 1529 errout: 1530 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name)); 1531 success: 1532 dx_release(frames); 1533 return bh; 1534 } 1535 1536 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 1537 { 1538 struct inode *inode; 1539 struct ext4_dir_entry_2 *de; 1540 struct buffer_head *bh; 1541 1542 if (ext4_encrypted_inode(dir)) { 1543 int res = fscrypt_get_encryption_info(dir); 1544 1545 /* 1546 * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is 1547 * created while the directory was encrypted and we 1548 * have access to the key. 1549 */ 1550 if (fscrypt_has_encryption_key(dir)) 1551 fscrypt_set_encrypted_dentry(dentry); 1552 fscrypt_set_d_op(dentry); 1553 if (res && res != -ENOKEY) 1554 return ERR_PTR(res); 1555 } 1556 1557 if (dentry->d_name.len > EXT4_NAME_LEN) 1558 return ERR_PTR(-ENAMETOOLONG); 1559 1560 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 1561 if (IS_ERR(bh)) 1562 return (struct dentry *) bh; 1563 inode = NULL; 1564 if (bh) { 1565 __u32 ino = le32_to_cpu(de->inode); 1566 brelse(bh); 1567 if (!ext4_valid_inum(dir->i_sb, ino)) { 1568 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); 1569 return ERR_PTR(-EFSCORRUPTED); 1570 } 1571 if (unlikely(ino == dir->i_ino)) { 1572 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir", 1573 dentry); 1574 return ERR_PTR(-EFSCORRUPTED); 1575 } 1576 inode = ext4_iget_normal(dir->i_sb, ino); 1577 if (inode == ERR_PTR(-ESTALE)) { 1578 EXT4_ERROR_INODE(dir, 1579 "deleted inode referenced: %u", 1580 ino); 1581 return ERR_PTR(-EFSCORRUPTED); 1582 } 1583 if (!IS_ERR(inode) && ext4_encrypted_inode(dir) && 1584 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && 1585 !fscrypt_has_permitted_context(dir, inode)) { 1586 ext4_warning(inode->i_sb, 1587 "Inconsistent encryption contexts: %lu/%lu", 1588 dir->i_ino, inode->i_ino); 1589 iput(inode); 1590 return ERR_PTR(-EPERM); 1591 } 1592 } 1593 return d_splice_alias(inode, dentry); 1594 } 1595 1596 1597 struct dentry *ext4_get_parent(struct dentry *child) 1598 { 1599 __u32 ino; 1600 static const struct qstr dotdot = QSTR_INIT("..", 2); 1601 struct ext4_dir_entry_2 * de; 1602 struct buffer_head *bh; 1603 1604 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL); 1605 if (IS_ERR(bh)) 1606 return (struct dentry *) bh; 1607 if (!bh) 1608 return ERR_PTR(-ENOENT); 1609 ino = le32_to_cpu(de->inode); 1610 brelse(bh); 1611 1612 if (!ext4_valid_inum(child->d_sb, ino)) { 1613 EXT4_ERROR_INODE(d_inode(child), 1614 "bad parent inode number: %u", ino); 1615 return ERR_PTR(-EFSCORRUPTED); 1616 } 1617 1618 return d_obtain_alias(ext4_iget_normal(child->d_sb, ino)); 1619 } 1620 1621 /* 1622 * Move count entries from end of map between two memory locations. 1623 * Returns pointer to last entry moved. 1624 */ 1625 static struct ext4_dir_entry_2 * 1626 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, 1627 unsigned blocksize) 1628 { 1629 unsigned rec_len = 0; 1630 1631 while (count--) { 1632 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) 1633 (from + (map->offs<<2)); 1634 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1635 memcpy (to, de, rec_len); 1636 ((struct ext4_dir_entry_2 *) to)->rec_len = 1637 ext4_rec_len_to_disk(rec_len, blocksize); 1638 de->inode = 0; 1639 map++; 1640 to += rec_len; 1641 } 1642 return (struct ext4_dir_entry_2 *) (to - rec_len); 1643 } 1644 1645 /* 1646 * Compact each dir entry in the range to the minimal rec_len. 1647 * Returns pointer to last entry in range. 1648 */ 1649 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) 1650 { 1651 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; 1652 unsigned rec_len = 0; 1653 1654 prev = to = de; 1655 while ((char*)de < base + blocksize) { 1656 next = ext4_next_entry(de, blocksize); 1657 if (de->inode && de->name_len) { 1658 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1659 if (de > to) 1660 memmove(to, de, rec_len); 1661 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); 1662 prev = to; 1663 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); 1664 } 1665 de = next; 1666 } 1667 return prev; 1668 } 1669 1670 /* 1671 * Split a full leaf block to make room for a new dir entry. 1672 * Allocate a new block, and move entries so that they are approx. equally full. 1673 * Returns pointer to de in block into which the new entry will be inserted. 1674 */ 1675 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1676 struct buffer_head **bh,struct dx_frame *frame, 1677 struct dx_hash_info *hinfo) 1678 { 1679 unsigned blocksize = dir->i_sb->s_blocksize; 1680 unsigned count, continued; 1681 struct buffer_head *bh2; 1682 ext4_lblk_t newblock; 1683 u32 hash2; 1684 struct dx_map_entry *map; 1685 char *data1 = (*bh)->b_data, *data2; 1686 unsigned split, move, size; 1687 struct ext4_dir_entry_2 *de = NULL, *de2; 1688 struct ext4_dir_entry_tail *t; 1689 int csum_size = 0; 1690 int err = 0, i; 1691 1692 if (ext4_has_metadata_csum(dir->i_sb)) 1693 csum_size = sizeof(struct ext4_dir_entry_tail); 1694 1695 bh2 = ext4_append(handle, dir, &newblock); 1696 if (IS_ERR(bh2)) { 1697 brelse(*bh); 1698 *bh = NULL; 1699 return (struct ext4_dir_entry_2 *) bh2; 1700 } 1701 1702 BUFFER_TRACE(*bh, "get_write_access"); 1703 err = ext4_journal_get_write_access(handle, *bh); 1704 if (err) 1705 goto journal_error; 1706 1707 BUFFER_TRACE(frame->bh, "get_write_access"); 1708 err = ext4_journal_get_write_access(handle, frame->bh); 1709 if (err) 1710 goto journal_error; 1711 1712 data2 = bh2->b_data; 1713 1714 /* create map in the end of data2 block */ 1715 map = (struct dx_map_entry *) (data2 + blocksize); 1716 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1, 1717 blocksize, hinfo, map); 1718 map -= count; 1719 dx_sort_map(map, count); 1720 /* Split the existing block in the middle, size-wise */ 1721 size = 0; 1722 move = 0; 1723 for (i = count-1; i >= 0; i--) { 1724 /* is more than half of this entry in 2nd half of the block? */ 1725 if (size + map[i].size/2 > blocksize/2) 1726 break; 1727 size += map[i].size; 1728 move++; 1729 } 1730 /* map index at which we will split */ 1731 split = count - move; 1732 hash2 = map[split].hash; 1733 continued = hash2 == map[split - 1].hash; 1734 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", 1735 (unsigned long)dx_get_block(frame->at), 1736 hash2, split, count-split)); 1737 1738 /* Fancy dance to stay within two buffers */ 1739 de2 = dx_move_dirents(data1, data2, map + split, count - split, 1740 blocksize); 1741 de = dx_pack_dirents(data1, blocksize); 1742 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1743 (char *) de, 1744 blocksize); 1745 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - 1746 (char *) de2, 1747 blocksize); 1748 if (csum_size) { 1749 t = EXT4_DIRENT_TAIL(data2, blocksize); 1750 initialize_dirent_tail(t, blocksize); 1751 1752 t = EXT4_DIRENT_TAIL(data1, blocksize); 1753 initialize_dirent_tail(t, blocksize); 1754 } 1755 1756 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1, 1757 blocksize, 1)); 1758 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2, 1759 blocksize, 1)); 1760 1761 /* Which block gets the new entry? */ 1762 if (hinfo->hash >= hash2) { 1763 swap(*bh, bh2); 1764 de = de2; 1765 } 1766 dx_insert_block(frame, hash2 + continued, newblock); 1767 err = ext4_handle_dirty_dirent_node(handle, dir, bh2); 1768 if (err) 1769 goto journal_error; 1770 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1771 if (err) 1772 goto journal_error; 1773 brelse(bh2); 1774 dxtrace(dx_show_index("frame", frame->entries)); 1775 return de; 1776 1777 journal_error: 1778 brelse(*bh); 1779 brelse(bh2); 1780 *bh = NULL; 1781 ext4_std_error(dir->i_sb, err); 1782 return ERR_PTR(err); 1783 } 1784 1785 int ext4_find_dest_de(struct inode *dir, struct inode *inode, 1786 struct buffer_head *bh, 1787 void *buf, int buf_size, 1788 struct ext4_filename *fname, 1789 struct ext4_dir_entry_2 **dest_de) 1790 { 1791 struct ext4_dir_entry_2 *de; 1792 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname)); 1793 int nlen, rlen; 1794 unsigned int offset = 0; 1795 char *top; 1796 1797 de = (struct ext4_dir_entry_2 *)buf; 1798 top = buf + buf_size - reclen; 1799 while ((char *) de <= top) { 1800 if (ext4_check_dir_entry(dir, NULL, de, bh, 1801 buf, buf_size, offset)) 1802 return -EFSCORRUPTED; 1803 if (ext4_match(fname, de)) 1804 return -EEXIST; 1805 nlen = EXT4_DIR_REC_LEN(de->name_len); 1806 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1807 if ((de->inode ? rlen - nlen : rlen) >= reclen) 1808 break; 1809 de = (struct ext4_dir_entry_2 *)((char *)de + rlen); 1810 offset += rlen; 1811 } 1812 if ((char *) de > top) 1813 return -ENOSPC; 1814 1815 *dest_de = de; 1816 return 0; 1817 } 1818 1819 void ext4_insert_dentry(struct inode *inode, 1820 struct ext4_dir_entry_2 *de, 1821 int buf_size, 1822 struct ext4_filename *fname) 1823 { 1824 1825 int nlen, rlen; 1826 1827 nlen = EXT4_DIR_REC_LEN(de->name_len); 1828 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1829 if (de->inode) { 1830 struct ext4_dir_entry_2 *de1 = 1831 (struct ext4_dir_entry_2 *)((char *)de + nlen); 1832 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); 1833 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); 1834 de = de1; 1835 } 1836 de->file_type = EXT4_FT_UNKNOWN; 1837 de->inode = cpu_to_le32(inode->i_ino); 1838 ext4_set_de_type(inode->i_sb, de, inode->i_mode); 1839 de->name_len = fname_len(fname); 1840 memcpy(de->name, fname_name(fname), fname_len(fname)); 1841 } 1842 1843 /* 1844 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1845 * it points to a directory entry which is guaranteed to be large 1846 * enough for new directory entry. If de is NULL, then 1847 * add_dirent_to_buf will attempt search the directory block for 1848 * space. It will return -ENOSPC if no space is available, and -EIO 1849 * and -EEXIST if directory entry already exists. 1850 */ 1851 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname, 1852 struct inode *dir, 1853 struct inode *inode, struct ext4_dir_entry_2 *de, 1854 struct buffer_head *bh) 1855 { 1856 unsigned int blocksize = dir->i_sb->s_blocksize; 1857 int csum_size = 0; 1858 int err; 1859 1860 if (ext4_has_metadata_csum(inode->i_sb)) 1861 csum_size = sizeof(struct ext4_dir_entry_tail); 1862 1863 if (!de) { 1864 err = ext4_find_dest_de(dir, inode, bh, bh->b_data, 1865 blocksize - csum_size, fname, &de); 1866 if (err) 1867 return err; 1868 } 1869 BUFFER_TRACE(bh, "get_write_access"); 1870 err = ext4_journal_get_write_access(handle, bh); 1871 if (err) { 1872 ext4_std_error(dir->i_sb, err); 1873 return err; 1874 } 1875 1876 /* By now the buffer is marked for journaling */ 1877 ext4_insert_dentry(inode, de, blocksize, fname); 1878 1879 /* 1880 * XXX shouldn't update any times until successful 1881 * completion of syscall, but too many callers depend 1882 * on this. 1883 * 1884 * XXX similarly, too many callers depend on 1885 * ext4_new_inode() setting the times, but error 1886 * recovery deletes the inode, so the worst that can 1887 * happen is that the times are slightly out of date 1888 * and/or different from the directory change time. 1889 */ 1890 dir->i_mtime = dir->i_ctime = current_time(dir); 1891 ext4_update_dx_flag(dir); 1892 inode_inc_iversion(dir); 1893 ext4_mark_inode_dirty(handle, dir); 1894 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 1895 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 1896 if (err) 1897 ext4_std_error(dir->i_sb, err); 1898 return 0; 1899 } 1900 1901 /* 1902 * This converts a one block unindexed directory to a 3 block indexed 1903 * directory, and adds the dentry to the indexed directory. 1904 */ 1905 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, 1906 struct inode *dir, 1907 struct inode *inode, struct buffer_head *bh) 1908 { 1909 struct buffer_head *bh2; 1910 struct dx_root *root; 1911 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1912 struct dx_entry *entries; 1913 struct ext4_dir_entry_2 *de, *de2; 1914 struct ext4_dir_entry_tail *t; 1915 char *data1, *top; 1916 unsigned len; 1917 int retval; 1918 unsigned blocksize; 1919 ext4_lblk_t block; 1920 struct fake_dirent *fde; 1921 int csum_size = 0; 1922 1923 if (ext4_has_metadata_csum(inode->i_sb)) 1924 csum_size = sizeof(struct ext4_dir_entry_tail); 1925 1926 blocksize = dir->i_sb->s_blocksize; 1927 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); 1928 BUFFER_TRACE(bh, "get_write_access"); 1929 retval = ext4_journal_get_write_access(handle, bh); 1930 if (retval) { 1931 ext4_std_error(dir->i_sb, retval); 1932 brelse(bh); 1933 return retval; 1934 } 1935 root = (struct dx_root *) bh->b_data; 1936 1937 /* The 0th block becomes the root, move the dirents out */ 1938 fde = &root->dotdot; 1939 de = (struct ext4_dir_entry_2 *)((char *)fde + 1940 ext4_rec_len_from_disk(fde->rec_len, blocksize)); 1941 if ((char *) de >= (((char *) root) + blocksize)) { 1942 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); 1943 brelse(bh); 1944 return -EFSCORRUPTED; 1945 } 1946 len = ((char *) root) + (blocksize - csum_size) - (char *) de; 1947 1948 /* Allocate new block for the 0th block's dirents */ 1949 bh2 = ext4_append(handle, dir, &block); 1950 if (IS_ERR(bh2)) { 1951 brelse(bh); 1952 return PTR_ERR(bh2); 1953 } 1954 ext4_set_inode_flag(dir, EXT4_INODE_INDEX); 1955 data1 = bh2->b_data; 1956 1957 memcpy (data1, de, len); 1958 de = (struct ext4_dir_entry_2 *) data1; 1959 top = data1 + len; 1960 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) 1961 de = de2; 1962 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1963 (char *) de, 1964 blocksize); 1965 1966 if (csum_size) { 1967 t = EXT4_DIRENT_TAIL(data1, blocksize); 1968 initialize_dirent_tail(t, blocksize); 1969 } 1970 1971 /* Initialize the root; the dot dirents already exist */ 1972 de = (struct ext4_dir_entry_2 *) (&root->dotdot); 1973 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), 1974 blocksize); 1975 memset (&root->info, 0, sizeof(root->info)); 1976 root->info.info_length = sizeof(root->info); 1977 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1978 entries = root->entries; 1979 dx_set_block(entries, 1); 1980 dx_set_count(entries, 1); 1981 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); 1982 1983 /* Initialize as for dx_probe */ 1984 fname->hinfo.hash_version = root->info.hash_version; 1985 if (fname->hinfo.hash_version <= DX_HASH_TEA) 1986 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 1987 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1988 ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo); 1989 1990 memset(frames, 0, sizeof(frames)); 1991 frame = frames; 1992 frame->entries = entries; 1993 frame->at = entries; 1994 frame->bh = bh; 1995 1996 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1997 if (retval) 1998 goto out_frames; 1999 retval = ext4_handle_dirty_dirent_node(handle, dir, bh2); 2000 if (retval) 2001 goto out_frames; 2002 2003 de = do_split(handle,dir, &bh2, frame, &fname->hinfo); 2004 if (IS_ERR(de)) { 2005 retval = PTR_ERR(de); 2006 goto out_frames; 2007 } 2008 2009 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2); 2010 out_frames: 2011 /* 2012 * Even if the block split failed, we have to properly write 2013 * out all the changes we did so far. Otherwise we can end up 2014 * with corrupted filesystem. 2015 */ 2016 if (retval) 2017 ext4_mark_inode_dirty(handle, dir); 2018 dx_release(frames); 2019 brelse(bh2); 2020 return retval; 2021 } 2022 2023 /* 2024 * ext4_add_entry() 2025 * 2026 * adds a file entry to the specified directory, using the same 2027 * semantics as ext4_find_entry(). It returns NULL if it failed. 2028 * 2029 * NOTE!! The inode part of 'de' is left at 0 - which means you 2030 * may not sleep between calling this and putting something into 2031 * the entry, as someone else might have used it while you slept. 2032 */ 2033 static int ext4_add_entry(handle_t *handle, struct dentry *dentry, 2034 struct inode *inode) 2035 { 2036 struct inode *dir = d_inode(dentry->d_parent); 2037 struct buffer_head *bh = NULL; 2038 struct ext4_dir_entry_2 *de; 2039 struct ext4_dir_entry_tail *t; 2040 struct super_block *sb; 2041 struct ext4_filename fname; 2042 int retval; 2043 int dx_fallback=0; 2044 unsigned blocksize; 2045 ext4_lblk_t block, blocks; 2046 int csum_size = 0; 2047 2048 if (ext4_has_metadata_csum(inode->i_sb)) 2049 csum_size = sizeof(struct ext4_dir_entry_tail); 2050 2051 sb = dir->i_sb; 2052 blocksize = sb->s_blocksize; 2053 if (!dentry->d_name.len) 2054 return -EINVAL; 2055 2056 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname); 2057 if (retval) 2058 return retval; 2059 2060 if (ext4_has_inline_data(dir)) { 2061 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode); 2062 if (retval < 0) 2063 goto out; 2064 if (retval == 1) { 2065 retval = 0; 2066 goto out; 2067 } 2068 } 2069 2070 if (is_dx(dir)) { 2071 retval = ext4_dx_add_entry(handle, &fname, dir, inode); 2072 if (!retval || (retval != ERR_BAD_DX_DIR)) 2073 goto out; 2074 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); 2075 dx_fallback++; 2076 ext4_mark_inode_dirty(handle, dir); 2077 } 2078 blocks = dir->i_size >> sb->s_blocksize_bits; 2079 for (block = 0; block < blocks; block++) { 2080 bh = ext4_read_dirblock(dir, block, DIRENT); 2081 if (IS_ERR(bh)) { 2082 retval = PTR_ERR(bh); 2083 bh = NULL; 2084 goto out; 2085 } 2086 retval = add_dirent_to_buf(handle, &fname, dir, inode, 2087 NULL, bh); 2088 if (retval != -ENOSPC) 2089 goto out; 2090 2091 if (blocks == 1 && !dx_fallback && 2092 ext4_has_feature_dir_index(sb)) { 2093 retval = make_indexed_dir(handle, &fname, dir, 2094 inode, bh); 2095 bh = NULL; /* make_indexed_dir releases bh */ 2096 goto out; 2097 } 2098 brelse(bh); 2099 } 2100 bh = ext4_append(handle, dir, &block); 2101 if (IS_ERR(bh)) { 2102 retval = PTR_ERR(bh); 2103 bh = NULL; 2104 goto out; 2105 } 2106 de = (struct ext4_dir_entry_2 *) bh->b_data; 2107 de->inode = 0; 2108 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize); 2109 2110 if (csum_size) { 2111 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize); 2112 initialize_dirent_tail(t, blocksize); 2113 } 2114 2115 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh); 2116 out: 2117 ext4_fname_free_filename(&fname); 2118 brelse(bh); 2119 if (retval == 0) 2120 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); 2121 return retval; 2122 } 2123 2124 /* 2125 * Returns 0 for success, or a negative error value 2126 */ 2127 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 2128 struct inode *dir, struct inode *inode) 2129 { 2130 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 2131 struct dx_entry *entries, *at; 2132 struct buffer_head *bh; 2133 struct super_block *sb = dir->i_sb; 2134 struct ext4_dir_entry_2 *de; 2135 int restart; 2136 int err; 2137 2138 again: 2139 restart = 0; 2140 frame = dx_probe(fname, dir, NULL, frames); 2141 if (IS_ERR(frame)) 2142 return PTR_ERR(frame); 2143 entries = frame->entries; 2144 at = frame->at; 2145 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT); 2146 if (IS_ERR(bh)) { 2147 err = PTR_ERR(bh); 2148 bh = NULL; 2149 goto cleanup; 2150 } 2151 2152 BUFFER_TRACE(bh, "get_write_access"); 2153 err = ext4_journal_get_write_access(handle, bh); 2154 if (err) 2155 goto journal_error; 2156 2157 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh); 2158 if (err != -ENOSPC) 2159 goto cleanup; 2160 2161 err = 0; 2162 /* Block full, should compress but for now just split */ 2163 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n", 2164 dx_get_count(entries), dx_get_limit(entries))); 2165 /* Need to split index? */ 2166 if (dx_get_count(entries) == dx_get_limit(entries)) { 2167 ext4_lblk_t newblock; 2168 int levels = frame - frames + 1; 2169 unsigned int icount; 2170 int add_level = 1; 2171 struct dx_entry *entries2; 2172 struct dx_node *node2; 2173 struct buffer_head *bh2; 2174 2175 while (frame > frames) { 2176 if (dx_get_count((frame - 1)->entries) < 2177 dx_get_limit((frame - 1)->entries)) { 2178 add_level = 0; 2179 break; 2180 } 2181 frame--; /* split higher index block */ 2182 at = frame->at; 2183 entries = frame->entries; 2184 restart = 1; 2185 } 2186 if (add_level && levels == ext4_dir_htree_level(sb)) { 2187 ext4_warning(sb, "Directory (ino: %lu) index full, " 2188 "reach max htree level :%d", 2189 dir->i_ino, levels); 2190 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) { 2191 ext4_warning(sb, "Large directory feature is " 2192 "not enabled on this " 2193 "filesystem"); 2194 } 2195 err = -ENOSPC; 2196 goto cleanup; 2197 } 2198 icount = dx_get_count(entries); 2199 bh2 = ext4_append(handle, dir, &newblock); 2200 if (IS_ERR(bh2)) { 2201 err = PTR_ERR(bh2); 2202 goto cleanup; 2203 } 2204 node2 = (struct dx_node *)(bh2->b_data); 2205 entries2 = node2->entries; 2206 memset(&node2->fake, 0, sizeof(struct fake_dirent)); 2207 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, 2208 sb->s_blocksize); 2209 BUFFER_TRACE(frame->bh, "get_write_access"); 2210 err = ext4_journal_get_write_access(handle, frame->bh); 2211 if (err) 2212 goto journal_error; 2213 if (!add_level) { 2214 unsigned icount1 = icount/2, icount2 = icount - icount1; 2215 unsigned hash2 = dx_get_hash(entries + icount1); 2216 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n", 2217 icount1, icount2)); 2218 2219 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 2220 err = ext4_journal_get_write_access(handle, 2221 (frame - 1)->bh); 2222 if (err) 2223 goto journal_error; 2224 2225 memcpy((char *) entries2, (char *) (entries + icount1), 2226 icount2 * sizeof(struct dx_entry)); 2227 dx_set_count(entries, icount1); 2228 dx_set_count(entries2, icount2); 2229 dx_set_limit(entries2, dx_node_limit(dir)); 2230 2231 /* Which index block gets the new entry? */ 2232 if (at - entries >= icount1) { 2233 frame->at = at = at - entries - icount1 + entries2; 2234 frame->entries = entries = entries2; 2235 swap(frame->bh, bh2); 2236 } 2237 dx_insert_block((frame - 1), hash2, newblock); 2238 dxtrace(dx_show_index("node", frame->entries)); 2239 dxtrace(dx_show_index("node", 2240 ((struct dx_node *) bh2->b_data)->entries)); 2241 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2242 if (err) 2243 goto journal_error; 2244 brelse (bh2); 2245 err = ext4_handle_dirty_dx_node(handle, dir, 2246 (frame - 1)->bh); 2247 if (err) 2248 goto journal_error; 2249 if (restart) { 2250 err = ext4_handle_dirty_dx_node(handle, dir, 2251 frame->bh); 2252 goto journal_error; 2253 } 2254 } else { 2255 struct dx_root *dxroot; 2256 memcpy((char *) entries2, (char *) entries, 2257 icount * sizeof(struct dx_entry)); 2258 dx_set_limit(entries2, dx_node_limit(dir)); 2259 2260 /* Set up root */ 2261 dx_set_count(entries, 1); 2262 dx_set_block(entries + 0, newblock); 2263 dxroot = (struct dx_root *)frames[0].bh->b_data; 2264 dxroot->info.indirect_levels += 1; 2265 dxtrace(printk(KERN_DEBUG 2266 "Creating %d level index...\n", 2267 info->indirect_levels)); 2268 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2269 if (err) 2270 goto journal_error; 2271 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2272 brelse(bh2); 2273 restart = 1; 2274 goto journal_error; 2275 } 2276 } 2277 de = do_split(handle, dir, &bh, frame, &fname->hinfo); 2278 if (IS_ERR(de)) { 2279 err = PTR_ERR(de); 2280 goto cleanup; 2281 } 2282 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh); 2283 goto cleanup; 2284 2285 journal_error: 2286 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */ 2287 cleanup: 2288 brelse(bh); 2289 dx_release(frames); 2290 /* @restart is true means htree-path has been changed, we need to 2291 * repeat dx_probe() to find out valid htree-path 2292 */ 2293 if (restart && err == 0) 2294 goto again; 2295 return err; 2296 } 2297 2298 /* 2299 * ext4_generic_delete_entry deletes a directory entry by merging it 2300 * with the previous entry 2301 */ 2302 int ext4_generic_delete_entry(handle_t *handle, 2303 struct inode *dir, 2304 struct ext4_dir_entry_2 *de_del, 2305 struct buffer_head *bh, 2306 void *entry_buf, 2307 int buf_size, 2308 int csum_size) 2309 { 2310 struct ext4_dir_entry_2 *de, *pde; 2311 unsigned int blocksize = dir->i_sb->s_blocksize; 2312 int i; 2313 2314 i = 0; 2315 pde = NULL; 2316 de = (struct ext4_dir_entry_2 *)entry_buf; 2317 while (i < buf_size - csum_size) { 2318 if (ext4_check_dir_entry(dir, NULL, de, bh, 2319 bh->b_data, bh->b_size, i)) 2320 return -EFSCORRUPTED; 2321 if (de == de_del) { 2322 if (pde) 2323 pde->rec_len = ext4_rec_len_to_disk( 2324 ext4_rec_len_from_disk(pde->rec_len, 2325 blocksize) + 2326 ext4_rec_len_from_disk(de->rec_len, 2327 blocksize), 2328 blocksize); 2329 else 2330 de->inode = 0; 2331 inode_inc_iversion(dir); 2332 return 0; 2333 } 2334 i += ext4_rec_len_from_disk(de->rec_len, blocksize); 2335 pde = de; 2336 de = ext4_next_entry(de, blocksize); 2337 } 2338 return -ENOENT; 2339 } 2340 2341 static int ext4_delete_entry(handle_t *handle, 2342 struct inode *dir, 2343 struct ext4_dir_entry_2 *de_del, 2344 struct buffer_head *bh) 2345 { 2346 int err, csum_size = 0; 2347 2348 if (ext4_has_inline_data(dir)) { 2349 int has_inline_data = 1; 2350 err = ext4_delete_inline_entry(handle, dir, de_del, bh, 2351 &has_inline_data); 2352 if (has_inline_data) 2353 return err; 2354 } 2355 2356 if (ext4_has_metadata_csum(dir->i_sb)) 2357 csum_size = sizeof(struct ext4_dir_entry_tail); 2358 2359 BUFFER_TRACE(bh, "get_write_access"); 2360 err = ext4_journal_get_write_access(handle, bh); 2361 if (unlikely(err)) 2362 goto out; 2363 2364 err = ext4_generic_delete_entry(handle, dir, de_del, 2365 bh, bh->b_data, 2366 dir->i_sb->s_blocksize, csum_size); 2367 if (err) 2368 goto out; 2369 2370 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 2371 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 2372 if (unlikely(err)) 2373 goto out; 2374 2375 return 0; 2376 out: 2377 if (err != -ENOENT) 2378 ext4_std_error(dir->i_sb, err); 2379 return err; 2380 } 2381 2382 /* 2383 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2 2384 * since this indicates that nlinks count was previously 1 to avoid overflowing 2385 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean 2386 * that subdirectory link counts are not being maintained accurately. 2387 * 2388 * The caller has already checked for i_nlink overflow in case the DIR_LINK 2389 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy 2390 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set 2391 * on regular files) and to avoid creating huge/slow non-HTREE directories. 2392 */ 2393 static void ext4_inc_count(handle_t *handle, struct inode *inode) 2394 { 2395 inc_nlink(inode); 2396 if (is_dx(inode) && 2397 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2)) 2398 set_nlink(inode, 1); 2399 } 2400 2401 /* 2402 * If a directory had nlink == 1, then we should let it be 1. This indicates 2403 * directory has >EXT4_LINK_MAX subdirs. 2404 */ 2405 static void ext4_dec_count(handle_t *handle, struct inode *inode) 2406 { 2407 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) 2408 drop_nlink(inode); 2409 } 2410 2411 2412 static int ext4_add_nondir(handle_t *handle, 2413 struct dentry *dentry, struct inode *inode) 2414 { 2415 int err = ext4_add_entry(handle, dentry, inode); 2416 if (!err) { 2417 ext4_mark_inode_dirty(handle, inode); 2418 unlock_new_inode(inode); 2419 d_instantiate(dentry, inode); 2420 return 0; 2421 } 2422 drop_nlink(inode); 2423 unlock_new_inode(inode); 2424 iput(inode); 2425 return err; 2426 } 2427 2428 /* 2429 * By the time this is called, we already have created 2430 * the directory cache entry for the new file, but it 2431 * is so far negative - it has no inode. 2432 * 2433 * If the create succeeds, we fill in the inode information 2434 * with d_instantiate(). 2435 */ 2436 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, 2437 bool excl) 2438 { 2439 handle_t *handle; 2440 struct inode *inode; 2441 int err, credits, retries = 0; 2442 2443 err = dquot_initialize(dir); 2444 if (err) 2445 return err; 2446 2447 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2448 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2449 retry: 2450 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2451 NULL, EXT4_HT_DIR, credits); 2452 handle = ext4_journal_current_handle(); 2453 err = PTR_ERR(inode); 2454 if (!IS_ERR(inode)) { 2455 inode->i_op = &ext4_file_inode_operations; 2456 inode->i_fop = &ext4_file_operations; 2457 ext4_set_aops(inode); 2458 err = ext4_add_nondir(handle, dentry, inode); 2459 if (!err && IS_DIRSYNC(dir)) 2460 ext4_handle_sync(handle); 2461 } 2462 if (handle) 2463 ext4_journal_stop(handle); 2464 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2465 goto retry; 2466 return err; 2467 } 2468 2469 static int ext4_mknod(struct inode *dir, struct dentry *dentry, 2470 umode_t mode, dev_t rdev) 2471 { 2472 handle_t *handle; 2473 struct inode *inode; 2474 int err, credits, retries = 0; 2475 2476 err = dquot_initialize(dir); 2477 if (err) 2478 return err; 2479 2480 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2481 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2482 retry: 2483 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2484 NULL, EXT4_HT_DIR, credits); 2485 handle = ext4_journal_current_handle(); 2486 err = PTR_ERR(inode); 2487 if (!IS_ERR(inode)) { 2488 init_special_inode(inode, inode->i_mode, rdev); 2489 inode->i_op = &ext4_special_inode_operations; 2490 err = ext4_add_nondir(handle, dentry, inode); 2491 if (!err && IS_DIRSYNC(dir)) 2492 ext4_handle_sync(handle); 2493 } 2494 if (handle) 2495 ext4_journal_stop(handle); 2496 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2497 goto retry; 2498 return err; 2499 } 2500 2501 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 2502 { 2503 handle_t *handle; 2504 struct inode *inode; 2505 int err, retries = 0; 2506 2507 err = dquot_initialize(dir); 2508 if (err) 2509 return err; 2510 2511 retry: 2512 inode = ext4_new_inode_start_handle(dir, mode, 2513 NULL, 0, NULL, 2514 EXT4_HT_DIR, 2515 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 2516 4 + EXT4_XATTR_TRANS_BLOCKS); 2517 handle = ext4_journal_current_handle(); 2518 err = PTR_ERR(inode); 2519 if (!IS_ERR(inode)) { 2520 inode->i_op = &ext4_file_inode_operations; 2521 inode->i_fop = &ext4_file_operations; 2522 ext4_set_aops(inode); 2523 d_tmpfile(dentry, inode); 2524 err = ext4_orphan_add(handle, inode); 2525 if (err) 2526 goto err_unlock_inode; 2527 mark_inode_dirty(inode); 2528 unlock_new_inode(inode); 2529 } 2530 if (handle) 2531 ext4_journal_stop(handle); 2532 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2533 goto retry; 2534 return err; 2535 err_unlock_inode: 2536 ext4_journal_stop(handle); 2537 unlock_new_inode(inode); 2538 return err; 2539 } 2540 2541 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode, 2542 struct ext4_dir_entry_2 *de, 2543 int blocksize, int csum_size, 2544 unsigned int parent_ino, int dotdot_real_len) 2545 { 2546 de->inode = cpu_to_le32(inode->i_ino); 2547 de->name_len = 1; 2548 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), 2549 blocksize); 2550 strcpy(de->name, "."); 2551 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2552 2553 de = ext4_next_entry(de, blocksize); 2554 de->inode = cpu_to_le32(parent_ino); 2555 de->name_len = 2; 2556 if (!dotdot_real_len) 2557 de->rec_len = ext4_rec_len_to_disk(blocksize - 2558 (csum_size + EXT4_DIR_REC_LEN(1)), 2559 blocksize); 2560 else 2561 de->rec_len = ext4_rec_len_to_disk( 2562 EXT4_DIR_REC_LEN(de->name_len), blocksize); 2563 strcpy(de->name, ".."); 2564 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2565 2566 return ext4_next_entry(de, blocksize); 2567 } 2568 2569 static int ext4_init_new_dir(handle_t *handle, struct inode *dir, 2570 struct inode *inode) 2571 { 2572 struct buffer_head *dir_block = NULL; 2573 struct ext4_dir_entry_2 *de; 2574 struct ext4_dir_entry_tail *t; 2575 ext4_lblk_t block = 0; 2576 unsigned int blocksize = dir->i_sb->s_blocksize; 2577 int csum_size = 0; 2578 int err; 2579 2580 if (ext4_has_metadata_csum(dir->i_sb)) 2581 csum_size = sizeof(struct ext4_dir_entry_tail); 2582 2583 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { 2584 err = ext4_try_create_inline_dir(handle, dir, inode); 2585 if (err < 0 && err != -ENOSPC) 2586 goto out; 2587 if (!err) 2588 goto out; 2589 } 2590 2591 inode->i_size = 0; 2592 dir_block = ext4_append(handle, inode, &block); 2593 if (IS_ERR(dir_block)) 2594 return PTR_ERR(dir_block); 2595 de = (struct ext4_dir_entry_2 *)dir_block->b_data; 2596 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0); 2597 set_nlink(inode, 2); 2598 if (csum_size) { 2599 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize); 2600 initialize_dirent_tail(t, blocksize); 2601 } 2602 2603 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); 2604 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block); 2605 if (err) 2606 goto out; 2607 set_buffer_verified(dir_block); 2608 out: 2609 brelse(dir_block); 2610 return err; 2611 } 2612 2613 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2614 { 2615 handle_t *handle; 2616 struct inode *inode; 2617 int err, credits, retries = 0; 2618 2619 if (EXT4_DIR_LINK_MAX(dir)) 2620 return -EMLINK; 2621 2622 err = dquot_initialize(dir); 2623 if (err) 2624 return err; 2625 2626 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2627 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2628 retry: 2629 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode, 2630 &dentry->d_name, 2631 0, NULL, EXT4_HT_DIR, credits); 2632 handle = ext4_journal_current_handle(); 2633 err = PTR_ERR(inode); 2634 if (IS_ERR(inode)) 2635 goto out_stop; 2636 2637 inode->i_op = &ext4_dir_inode_operations; 2638 inode->i_fop = &ext4_dir_operations; 2639 err = ext4_init_new_dir(handle, dir, inode); 2640 if (err) 2641 goto out_clear_inode; 2642 err = ext4_mark_inode_dirty(handle, inode); 2643 if (!err) 2644 err = ext4_add_entry(handle, dentry, inode); 2645 if (err) { 2646 out_clear_inode: 2647 clear_nlink(inode); 2648 unlock_new_inode(inode); 2649 ext4_mark_inode_dirty(handle, inode); 2650 iput(inode); 2651 goto out_stop; 2652 } 2653 ext4_inc_count(handle, dir); 2654 ext4_update_dx_flag(dir); 2655 err = ext4_mark_inode_dirty(handle, dir); 2656 if (err) 2657 goto out_clear_inode; 2658 unlock_new_inode(inode); 2659 d_instantiate(dentry, inode); 2660 if (IS_DIRSYNC(dir)) 2661 ext4_handle_sync(handle); 2662 2663 out_stop: 2664 if (handle) 2665 ext4_journal_stop(handle); 2666 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2667 goto retry; 2668 return err; 2669 } 2670 2671 /* 2672 * routine to check that the specified directory is empty (for rmdir) 2673 */ 2674 bool ext4_empty_dir(struct inode *inode) 2675 { 2676 unsigned int offset; 2677 struct buffer_head *bh; 2678 struct ext4_dir_entry_2 *de, *de1; 2679 struct super_block *sb; 2680 2681 if (ext4_has_inline_data(inode)) { 2682 int has_inline_data = 1; 2683 int ret; 2684 2685 ret = empty_inline_dir(inode, &has_inline_data); 2686 if (has_inline_data) 2687 return ret; 2688 } 2689 2690 sb = inode->i_sb; 2691 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { 2692 EXT4_ERROR_INODE(inode, "invalid size"); 2693 return true; 2694 } 2695 bh = ext4_read_dirblock(inode, 0, EITHER); 2696 if (IS_ERR(bh)) 2697 return true; 2698 2699 de = (struct ext4_dir_entry_2 *) bh->b_data; 2700 de1 = ext4_next_entry(de, sb->s_blocksize); 2701 if (le32_to_cpu(de->inode) != inode->i_ino || 2702 le32_to_cpu(de1->inode) == 0 || 2703 strcmp(".", de->name) || strcmp("..", de1->name)) { 2704 ext4_warning_inode(inode, "directory missing '.' and/or '..'"); 2705 brelse(bh); 2706 return true; 2707 } 2708 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + 2709 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); 2710 de = ext4_next_entry(de1, sb->s_blocksize); 2711 while (offset < inode->i_size) { 2712 if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 2713 unsigned int lblock; 2714 brelse(bh); 2715 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); 2716 bh = ext4_read_dirblock(inode, lblock, EITHER); 2717 if (IS_ERR(bh)) 2718 return true; 2719 de = (struct ext4_dir_entry_2 *) bh->b_data; 2720 } 2721 if (ext4_check_dir_entry(inode, NULL, de, bh, 2722 bh->b_data, bh->b_size, offset)) { 2723 de = (struct ext4_dir_entry_2 *)(bh->b_data + 2724 sb->s_blocksize); 2725 offset = (offset | (sb->s_blocksize - 1)) + 1; 2726 continue; 2727 } 2728 if (le32_to_cpu(de->inode)) { 2729 brelse(bh); 2730 return false; 2731 } 2732 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2733 de = ext4_next_entry(de, sb->s_blocksize); 2734 } 2735 brelse(bh); 2736 return true; 2737 } 2738 2739 /* 2740 * ext4_orphan_add() links an unlinked or truncated inode into a list of 2741 * such inodes, starting at the superblock, in case we crash before the 2742 * file is closed/deleted, or in case the inode truncate spans multiple 2743 * transactions and the last transaction is not recovered after a crash. 2744 * 2745 * At filesystem recovery time, we walk this list deleting unlinked 2746 * inodes and truncating linked inodes in ext4_orphan_cleanup(). 2747 * 2748 * Orphan list manipulation functions must be called under i_mutex unless 2749 * we are just creating the inode or deleting it. 2750 */ 2751 int ext4_orphan_add(handle_t *handle, struct inode *inode) 2752 { 2753 struct super_block *sb = inode->i_sb; 2754 struct ext4_sb_info *sbi = EXT4_SB(sb); 2755 struct ext4_iloc iloc; 2756 int err = 0, rc; 2757 bool dirty = false; 2758 2759 if (!sbi->s_journal || is_bad_inode(inode)) 2760 return 0; 2761 2762 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2763 !inode_is_locked(inode)); 2764 /* 2765 * Exit early if inode already is on orphan list. This is a big speedup 2766 * since we don't have to contend on the global s_orphan_lock. 2767 */ 2768 if (!list_empty(&EXT4_I(inode)->i_orphan)) 2769 return 0; 2770 2771 /* 2772 * Orphan handling is only valid for files with data blocks 2773 * being truncated, or files being unlinked. Note that we either 2774 * hold i_mutex, or the inode can not be referenced from outside, 2775 * so i_nlink should not be bumped due to race 2776 */ 2777 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2778 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 2779 2780 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2781 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2782 if (err) 2783 goto out; 2784 2785 err = ext4_reserve_inode_write(handle, inode, &iloc); 2786 if (err) 2787 goto out; 2788 2789 mutex_lock(&sbi->s_orphan_lock); 2790 /* 2791 * Due to previous errors inode may be already a part of on-disk 2792 * orphan list. If so skip on-disk list modification. 2793 */ 2794 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) > 2795 (le32_to_cpu(sbi->s_es->s_inodes_count))) { 2796 /* Insert this inode at the head of the on-disk orphan list */ 2797 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan); 2798 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 2799 dirty = true; 2800 } 2801 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan); 2802 mutex_unlock(&sbi->s_orphan_lock); 2803 2804 if (dirty) { 2805 err = ext4_handle_dirty_super(handle, sb); 2806 rc = ext4_mark_iloc_dirty(handle, inode, &iloc); 2807 if (!err) 2808 err = rc; 2809 if (err) { 2810 /* 2811 * We have to remove inode from in-memory list if 2812 * addition to on disk orphan list failed. Stray orphan 2813 * list entries can cause panics at unmount time. 2814 */ 2815 mutex_lock(&sbi->s_orphan_lock); 2816 list_del_init(&EXT4_I(inode)->i_orphan); 2817 mutex_unlock(&sbi->s_orphan_lock); 2818 } 2819 } 2820 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 2821 jbd_debug(4, "orphan inode %lu will point to %d\n", 2822 inode->i_ino, NEXT_ORPHAN(inode)); 2823 out: 2824 ext4_std_error(sb, err); 2825 return err; 2826 } 2827 2828 /* 2829 * ext4_orphan_del() removes an unlinked or truncated inode from the list 2830 * of such inodes stored on disk, because it is finally being cleaned up. 2831 */ 2832 int ext4_orphan_del(handle_t *handle, struct inode *inode) 2833 { 2834 struct list_head *prev; 2835 struct ext4_inode_info *ei = EXT4_I(inode); 2836 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 2837 __u32 ino_next; 2838 struct ext4_iloc iloc; 2839 int err = 0; 2840 2841 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS)) 2842 return 0; 2843 2844 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2845 !inode_is_locked(inode)); 2846 /* Do this quick check before taking global s_orphan_lock. */ 2847 if (list_empty(&ei->i_orphan)) 2848 return 0; 2849 2850 if (handle) { 2851 /* Grab inode buffer early before taking global s_orphan_lock */ 2852 err = ext4_reserve_inode_write(handle, inode, &iloc); 2853 } 2854 2855 mutex_lock(&sbi->s_orphan_lock); 2856 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 2857 2858 prev = ei->i_orphan.prev; 2859 list_del_init(&ei->i_orphan); 2860 2861 /* If we're on an error path, we may not have a valid 2862 * transaction handle with which to update the orphan list on 2863 * disk, but we still need to remove the inode from the linked 2864 * list in memory. */ 2865 if (!handle || err) { 2866 mutex_unlock(&sbi->s_orphan_lock); 2867 goto out_err; 2868 } 2869 2870 ino_next = NEXT_ORPHAN(inode); 2871 if (prev == &sbi->s_orphan) { 2872 jbd_debug(4, "superblock will point to %u\n", ino_next); 2873 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2874 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2875 if (err) { 2876 mutex_unlock(&sbi->s_orphan_lock); 2877 goto out_brelse; 2878 } 2879 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 2880 mutex_unlock(&sbi->s_orphan_lock); 2881 err = ext4_handle_dirty_super(handle, inode->i_sb); 2882 } else { 2883 struct ext4_iloc iloc2; 2884 struct inode *i_prev = 2885 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; 2886 2887 jbd_debug(4, "orphan inode %lu will point to %u\n", 2888 i_prev->i_ino, ino_next); 2889 err = ext4_reserve_inode_write(handle, i_prev, &iloc2); 2890 if (err) { 2891 mutex_unlock(&sbi->s_orphan_lock); 2892 goto out_brelse; 2893 } 2894 NEXT_ORPHAN(i_prev) = ino_next; 2895 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); 2896 mutex_unlock(&sbi->s_orphan_lock); 2897 } 2898 if (err) 2899 goto out_brelse; 2900 NEXT_ORPHAN(inode) = 0; 2901 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 2902 out_err: 2903 ext4_std_error(inode->i_sb, err); 2904 return err; 2905 2906 out_brelse: 2907 brelse(iloc.bh); 2908 goto out_err; 2909 } 2910 2911 static int ext4_rmdir(struct inode *dir, struct dentry *dentry) 2912 { 2913 int retval; 2914 struct inode *inode; 2915 struct buffer_head *bh; 2916 struct ext4_dir_entry_2 *de; 2917 handle_t *handle = NULL; 2918 2919 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 2920 return -EIO; 2921 2922 /* Initialize quotas before so that eventual writes go in 2923 * separate transaction */ 2924 retval = dquot_initialize(dir); 2925 if (retval) 2926 return retval; 2927 retval = dquot_initialize(d_inode(dentry)); 2928 if (retval) 2929 return retval; 2930 2931 retval = -ENOENT; 2932 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 2933 if (IS_ERR(bh)) 2934 return PTR_ERR(bh); 2935 if (!bh) 2936 goto end_rmdir; 2937 2938 inode = d_inode(dentry); 2939 2940 retval = -EFSCORRUPTED; 2941 if (le32_to_cpu(de->inode) != inode->i_ino) 2942 goto end_rmdir; 2943 2944 retval = -ENOTEMPTY; 2945 if (!ext4_empty_dir(inode)) 2946 goto end_rmdir; 2947 2948 handle = ext4_journal_start(dir, EXT4_HT_DIR, 2949 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 2950 if (IS_ERR(handle)) { 2951 retval = PTR_ERR(handle); 2952 handle = NULL; 2953 goto end_rmdir; 2954 } 2955 2956 if (IS_DIRSYNC(dir)) 2957 ext4_handle_sync(handle); 2958 2959 retval = ext4_delete_entry(handle, dir, de, bh); 2960 if (retval) 2961 goto end_rmdir; 2962 if (!EXT4_DIR_LINK_EMPTY(inode)) 2963 ext4_warning_inode(inode, 2964 "empty directory '%.*s' has too many links (%u)", 2965 dentry->d_name.len, dentry->d_name.name, 2966 inode->i_nlink); 2967 inode->i_version++; 2968 clear_nlink(inode); 2969 /* There's no need to set i_disksize: the fact that i_nlink is 2970 * zero will ensure that the right thing happens during any 2971 * recovery. */ 2972 inode->i_size = 0; 2973 ext4_orphan_add(handle, inode); 2974 inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); 2975 ext4_mark_inode_dirty(handle, inode); 2976 ext4_dec_count(handle, dir); 2977 ext4_update_dx_flag(dir); 2978 ext4_mark_inode_dirty(handle, dir); 2979 2980 end_rmdir: 2981 brelse(bh); 2982 if (handle) 2983 ext4_journal_stop(handle); 2984 return retval; 2985 } 2986 2987 static int ext4_unlink(struct inode *dir, struct dentry *dentry) 2988 { 2989 int retval; 2990 struct inode *inode; 2991 struct buffer_head *bh; 2992 struct ext4_dir_entry_2 *de; 2993 handle_t *handle = NULL; 2994 2995 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 2996 return -EIO; 2997 2998 trace_ext4_unlink_enter(dir, dentry); 2999 /* Initialize quotas before so that eventual writes go 3000 * in separate transaction */ 3001 retval = dquot_initialize(dir); 3002 if (retval) 3003 return retval; 3004 retval = dquot_initialize(d_inode(dentry)); 3005 if (retval) 3006 return retval; 3007 3008 retval = -ENOENT; 3009 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 3010 if (IS_ERR(bh)) 3011 return PTR_ERR(bh); 3012 if (!bh) 3013 goto end_unlink; 3014 3015 inode = d_inode(dentry); 3016 3017 retval = -EFSCORRUPTED; 3018 if (le32_to_cpu(de->inode) != inode->i_ino) 3019 goto end_unlink; 3020 3021 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3022 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 3023 if (IS_ERR(handle)) { 3024 retval = PTR_ERR(handle); 3025 handle = NULL; 3026 goto end_unlink; 3027 } 3028 3029 if (IS_DIRSYNC(dir)) 3030 ext4_handle_sync(handle); 3031 3032 if (inode->i_nlink == 0) { 3033 ext4_warning_inode(inode, "Deleting file '%.*s' with no links", 3034 dentry->d_name.len, dentry->d_name.name); 3035 set_nlink(inode, 1); 3036 } 3037 retval = ext4_delete_entry(handle, dir, de, bh); 3038 if (retval) 3039 goto end_unlink; 3040 dir->i_ctime = dir->i_mtime = current_time(dir); 3041 ext4_update_dx_flag(dir); 3042 ext4_mark_inode_dirty(handle, dir); 3043 drop_nlink(inode); 3044 if (!inode->i_nlink) 3045 ext4_orphan_add(handle, inode); 3046 inode->i_ctime = current_time(inode); 3047 ext4_mark_inode_dirty(handle, inode); 3048 3049 end_unlink: 3050 brelse(bh); 3051 if (handle) 3052 ext4_journal_stop(handle); 3053 trace_ext4_unlink_exit(dentry, retval); 3054 return retval; 3055 } 3056 3057 static int ext4_symlink(struct inode *dir, 3058 struct dentry *dentry, const char *symname) 3059 { 3060 handle_t *handle; 3061 struct inode *inode; 3062 int err, len = strlen(symname); 3063 int credits; 3064 bool encryption_required; 3065 struct fscrypt_str disk_link; 3066 struct fscrypt_symlink_data *sd = NULL; 3067 3068 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3069 return -EIO; 3070 3071 disk_link.len = len + 1; 3072 disk_link.name = (char *) symname; 3073 3074 encryption_required = (ext4_encrypted_inode(dir) || 3075 DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb))); 3076 if (encryption_required) { 3077 err = fscrypt_get_encryption_info(dir); 3078 if (err) 3079 return err; 3080 if (!fscrypt_has_encryption_key(dir)) 3081 return -ENOKEY; 3082 disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + 3083 sizeof(struct fscrypt_symlink_data)); 3084 sd = kzalloc(disk_link.len, GFP_KERNEL); 3085 if (!sd) 3086 return -ENOMEM; 3087 } 3088 3089 if (disk_link.len > dir->i_sb->s_blocksize) { 3090 err = -ENAMETOOLONG; 3091 goto err_free_sd; 3092 } 3093 3094 err = dquot_initialize(dir); 3095 if (err) 3096 goto err_free_sd; 3097 3098 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3099 /* 3100 * For non-fast symlinks, we just allocate inode and put it on 3101 * orphan list in the first transaction => we need bitmap, 3102 * group descriptor, sb, inode block, quota blocks, and 3103 * possibly selinux xattr blocks. 3104 */ 3105 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 3106 EXT4_XATTR_TRANS_BLOCKS; 3107 } else { 3108 /* 3109 * Fast symlink. We have to add entry to directory 3110 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), 3111 * allocate new inode (bitmap, group descriptor, inode block, 3112 * quota blocks, sb is already counted in previous macros). 3113 */ 3114 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3115 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3; 3116 } 3117 3118 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO, 3119 &dentry->d_name, 0, NULL, 3120 EXT4_HT_DIR, credits); 3121 handle = ext4_journal_current_handle(); 3122 if (IS_ERR(inode)) { 3123 if (handle) 3124 ext4_journal_stop(handle); 3125 err = PTR_ERR(inode); 3126 goto err_free_sd; 3127 } 3128 3129 if (encryption_required) { 3130 struct qstr istr; 3131 struct fscrypt_str ostr = 3132 FSTR_INIT(sd->encrypted_path, disk_link.len); 3133 3134 istr.name = (const unsigned char *) symname; 3135 istr.len = len; 3136 err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); 3137 if (err) 3138 goto err_drop_inode; 3139 sd->len = cpu_to_le16(ostr.len); 3140 disk_link.name = (char *) sd; 3141 inode->i_op = &ext4_encrypted_symlink_inode_operations; 3142 } 3143 3144 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3145 if (!encryption_required) 3146 inode->i_op = &ext4_symlink_inode_operations; 3147 inode_nohighmem(inode); 3148 ext4_set_aops(inode); 3149 /* 3150 * We cannot call page_symlink() with transaction started 3151 * because it calls into ext4_write_begin() which can wait 3152 * for transaction commit if we are running out of space 3153 * and thus we deadlock. So we have to stop transaction now 3154 * and restart it when symlink contents is written. 3155 * 3156 * To keep fs consistent in case of crash, we have to put inode 3157 * to orphan list in the mean time. 3158 */ 3159 drop_nlink(inode); 3160 err = ext4_orphan_add(handle, inode); 3161 ext4_journal_stop(handle); 3162 handle = NULL; 3163 if (err) 3164 goto err_drop_inode; 3165 err = __page_symlink(inode, disk_link.name, disk_link.len, 1); 3166 if (err) 3167 goto err_drop_inode; 3168 /* 3169 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS 3170 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified 3171 */ 3172 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3173 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3174 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); 3175 if (IS_ERR(handle)) { 3176 err = PTR_ERR(handle); 3177 handle = NULL; 3178 goto err_drop_inode; 3179 } 3180 set_nlink(inode, 1); 3181 err = ext4_orphan_del(handle, inode); 3182 if (err) 3183 goto err_drop_inode; 3184 } else { 3185 /* clear the extent format for fast symlink */ 3186 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); 3187 if (!encryption_required) { 3188 inode->i_op = &ext4_fast_symlink_inode_operations; 3189 inode->i_link = (char *)&EXT4_I(inode)->i_data; 3190 } 3191 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name, 3192 disk_link.len); 3193 inode->i_size = disk_link.len - 1; 3194 } 3195 EXT4_I(inode)->i_disksize = inode->i_size; 3196 err = ext4_add_nondir(handle, dentry, inode); 3197 if (!err && IS_DIRSYNC(dir)) 3198 ext4_handle_sync(handle); 3199 3200 if (handle) 3201 ext4_journal_stop(handle); 3202 kfree(sd); 3203 return err; 3204 err_drop_inode: 3205 if (handle) 3206 ext4_journal_stop(handle); 3207 clear_nlink(inode); 3208 unlock_new_inode(inode); 3209 iput(inode); 3210 err_free_sd: 3211 kfree(sd); 3212 return err; 3213 } 3214 3215 static int ext4_link(struct dentry *old_dentry, 3216 struct inode *dir, struct dentry *dentry) 3217 { 3218 handle_t *handle; 3219 struct inode *inode = d_inode(old_dentry); 3220 int err, retries = 0; 3221 3222 if (inode->i_nlink >= EXT4_LINK_MAX) 3223 return -EMLINK; 3224 if (ext4_encrypted_inode(dir) && 3225 !fscrypt_has_permitted_context(dir, inode)) 3226 return -EPERM; 3227 3228 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) && 3229 (!projid_eq(EXT4_I(dir)->i_projid, 3230 EXT4_I(old_dentry->d_inode)->i_projid))) 3231 return -EXDEV; 3232 3233 err = dquot_initialize(dir); 3234 if (err) 3235 return err; 3236 3237 retry: 3238 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3239 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3240 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1); 3241 if (IS_ERR(handle)) 3242 return PTR_ERR(handle); 3243 3244 if (IS_DIRSYNC(dir)) 3245 ext4_handle_sync(handle); 3246 3247 inode->i_ctime = current_time(inode); 3248 ext4_inc_count(handle, inode); 3249 ihold(inode); 3250 3251 err = ext4_add_entry(handle, dentry, inode); 3252 if (!err) { 3253 ext4_mark_inode_dirty(handle, inode); 3254 /* this can happen only for tmpfile being 3255 * linked the first time 3256 */ 3257 if (inode->i_nlink == 1) 3258 ext4_orphan_del(handle, inode); 3259 d_instantiate(dentry, inode); 3260 } else { 3261 drop_nlink(inode); 3262 iput(inode); 3263 } 3264 ext4_journal_stop(handle); 3265 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 3266 goto retry; 3267 return err; 3268 } 3269 3270 3271 /* 3272 * Try to find buffer head where contains the parent block. 3273 * It should be the inode block if it is inlined or the 1st block 3274 * if it is a normal dir. 3275 */ 3276 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, 3277 struct inode *inode, 3278 int *retval, 3279 struct ext4_dir_entry_2 **parent_de, 3280 int *inlined) 3281 { 3282 struct buffer_head *bh; 3283 3284 if (!ext4_has_inline_data(inode)) { 3285 bh = ext4_read_dirblock(inode, 0, EITHER); 3286 if (IS_ERR(bh)) { 3287 *retval = PTR_ERR(bh); 3288 return NULL; 3289 } 3290 *parent_de = ext4_next_entry( 3291 (struct ext4_dir_entry_2 *)bh->b_data, 3292 inode->i_sb->s_blocksize); 3293 return bh; 3294 } 3295 3296 *inlined = 1; 3297 return ext4_get_first_inline_block(inode, parent_de, retval); 3298 } 3299 3300 struct ext4_renament { 3301 struct inode *dir; 3302 struct dentry *dentry; 3303 struct inode *inode; 3304 bool is_dir; 3305 int dir_nlink_delta; 3306 3307 /* entry for "dentry" */ 3308 struct buffer_head *bh; 3309 struct ext4_dir_entry_2 *de; 3310 int inlined; 3311 3312 /* entry for ".." in inode if it's a directory */ 3313 struct buffer_head *dir_bh; 3314 struct ext4_dir_entry_2 *parent_de; 3315 int dir_inlined; 3316 }; 3317 3318 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) 3319 { 3320 int retval; 3321 3322 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, 3323 &retval, &ent->parent_de, 3324 &ent->dir_inlined); 3325 if (!ent->dir_bh) 3326 return retval; 3327 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) 3328 return -EFSCORRUPTED; 3329 BUFFER_TRACE(ent->dir_bh, "get_write_access"); 3330 return ext4_journal_get_write_access(handle, ent->dir_bh); 3331 } 3332 3333 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, 3334 unsigned dir_ino) 3335 { 3336 int retval; 3337 3338 ent->parent_de->inode = cpu_to_le32(dir_ino); 3339 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); 3340 if (!ent->dir_inlined) { 3341 if (is_dx(ent->inode)) { 3342 retval = ext4_handle_dirty_dx_node(handle, 3343 ent->inode, 3344 ent->dir_bh); 3345 } else { 3346 retval = ext4_handle_dirty_dirent_node(handle, 3347 ent->inode, 3348 ent->dir_bh); 3349 } 3350 } else { 3351 retval = ext4_mark_inode_dirty(handle, ent->inode); 3352 } 3353 if (retval) { 3354 ext4_std_error(ent->dir->i_sb, retval); 3355 return retval; 3356 } 3357 return 0; 3358 } 3359 3360 static int ext4_setent(handle_t *handle, struct ext4_renament *ent, 3361 unsigned ino, unsigned file_type) 3362 { 3363 int retval; 3364 3365 BUFFER_TRACE(ent->bh, "get write access"); 3366 retval = ext4_journal_get_write_access(handle, ent->bh); 3367 if (retval) 3368 return retval; 3369 ent->de->inode = cpu_to_le32(ino); 3370 if (ext4_has_feature_filetype(ent->dir->i_sb)) 3371 ent->de->file_type = file_type; 3372 ent->dir->i_version++; 3373 ent->dir->i_ctime = ent->dir->i_mtime = 3374 current_time(ent->dir); 3375 ext4_mark_inode_dirty(handle, ent->dir); 3376 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); 3377 if (!ent->inlined) { 3378 retval = ext4_handle_dirty_dirent_node(handle, 3379 ent->dir, ent->bh); 3380 if (unlikely(retval)) { 3381 ext4_std_error(ent->dir->i_sb, retval); 3382 return retval; 3383 } 3384 } 3385 brelse(ent->bh); 3386 ent->bh = NULL; 3387 3388 return 0; 3389 } 3390 3391 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, 3392 const struct qstr *d_name) 3393 { 3394 int retval = -ENOENT; 3395 struct buffer_head *bh; 3396 struct ext4_dir_entry_2 *de; 3397 3398 bh = ext4_find_entry(dir, d_name, &de, NULL); 3399 if (IS_ERR(bh)) 3400 return PTR_ERR(bh); 3401 if (bh) { 3402 retval = ext4_delete_entry(handle, dir, de, bh); 3403 brelse(bh); 3404 } 3405 return retval; 3406 } 3407 3408 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent, 3409 int force_reread) 3410 { 3411 int retval; 3412 /* 3413 * ent->de could have moved from under us during htree split, so make 3414 * sure that we are deleting the right entry. We might also be pointing 3415 * to a stale entry in the unused part of ent->bh so just checking inum 3416 * and the name isn't enough. 3417 */ 3418 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || 3419 ent->de->name_len != ent->dentry->d_name.len || 3420 strncmp(ent->de->name, ent->dentry->d_name.name, 3421 ent->de->name_len) || 3422 force_reread) { 3423 retval = ext4_find_delete_entry(handle, ent->dir, 3424 &ent->dentry->d_name); 3425 } else { 3426 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); 3427 if (retval == -ENOENT) { 3428 retval = ext4_find_delete_entry(handle, ent->dir, 3429 &ent->dentry->d_name); 3430 } 3431 } 3432 3433 if (retval) { 3434 ext4_warning_inode(ent->dir, 3435 "Deleting old file: nlink %d, error=%d", 3436 ent->dir->i_nlink, retval); 3437 } 3438 } 3439 3440 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) 3441 { 3442 if (ent->dir_nlink_delta) { 3443 if (ent->dir_nlink_delta == -1) 3444 ext4_dec_count(handle, ent->dir); 3445 else 3446 ext4_inc_count(handle, ent->dir); 3447 ext4_mark_inode_dirty(handle, ent->dir); 3448 } 3449 } 3450 3451 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, 3452 int credits, handle_t **h) 3453 { 3454 struct inode *wh; 3455 handle_t *handle; 3456 int retries = 0; 3457 3458 /* 3459 * for inode block, sb block, group summaries, 3460 * and inode bitmap 3461 */ 3462 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + 3463 EXT4_XATTR_TRANS_BLOCKS + 4); 3464 retry: 3465 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, 3466 &ent->dentry->d_name, 0, NULL, 3467 EXT4_HT_DIR, credits); 3468 3469 handle = ext4_journal_current_handle(); 3470 if (IS_ERR(wh)) { 3471 if (handle) 3472 ext4_journal_stop(handle); 3473 if (PTR_ERR(wh) == -ENOSPC && 3474 ext4_should_retry_alloc(ent->dir->i_sb, &retries)) 3475 goto retry; 3476 } else { 3477 *h = handle; 3478 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); 3479 wh->i_op = &ext4_special_inode_operations; 3480 } 3481 return wh; 3482 } 3483 3484 /* 3485 * Anybody can rename anything with this: the permission checks are left to the 3486 * higher-level routines. 3487 * 3488 * n.b. old_{dentry,inode) refers to the source dentry/inode 3489 * while new_{dentry,inode) refers to the destination dentry/inode 3490 * This comes from rename(const char *oldpath, const char *newpath) 3491 */ 3492 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, 3493 struct inode *new_dir, struct dentry *new_dentry, 3494 unsigned int flags) 3495 { 3496 handle_t *handle = NULL; 3497 struct ext4_renament old = { 3498 .dir = old_dir, 3499 .dentry = old_dentry, 3500 .inode = d_inode(old_dentry), 3501 }; 3502 struct ext4_renament new = { 3503 .dir = new_dir, 3504 .dentry = new_dentry, 3505 .inode = d_inode(new_dentry), 3506 }; 3507 int force_reread; 3508 int retval; 3509 struct inode *whiteout = NULL; 3510 int credits; 3511 u8 old_file_type; 3512 3513 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && 3514 (!projid_eq(EXT4_I(new_dir)->i_projid, 3515 EXT4_I(old_dentry->d_inode)->i_projid))) 3516 return -EXDEV; 3517 3518 if ((ext4_encrypted_inode(old_dir) && 3519 !fscrypt_has_encryption_key(old_dir)) || 3520 (ext4_encrypted_inode(new_dir) && 3521 !fscrypt_has_encryption_key(new_dir))) 3522 return -ENOKEY; 3523 3524 retval = dquot_initialize(old.dir); 3525 if (retval) 3526 return retval; 3527 retval = dquot_initialize(new.dir); 3528 if (retval) 3529 return retval; 3530 3531 /* Initialize quotas before so that eventual writes go 3532 * in separate transaction */ 3533 if (new.inode) { 3534 retval = dquot_initialize(new.inode); 3535 if (retval) 3536 return retval; 3537 } 3538 3539 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); 3540 if (IS_ERR(old.bh)) 3541 return PTR_ERR(old.bh); 3542 /* 3543 * Check for inode number is _not_ due to possible IO errors. 3544 * We might rmdir the source, keep it as pwd of some process 3545 * and merrily kill the link to whatever was created under the 3546 * same name. Goodbye sticky bit ;-< 3547 */ 3548 retval = -ENOENT; 3549 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3550 goto end_rename; 3551 3552 if ((old.dir != new.dir) && 3553 ext4_encrypted_inode(new.dir) && 3554 !fscrypt_has_permitted_context(new.dir, old.inode)) { 3555 retval = -EPERM; 3556 goto end_rename; 3557 } 3558 3559 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3560 &new.de, &new.inlined); 3561 if (IS_ERR(new.bh)) { 3562 retval = PTR_ERR(new.bh); 3563 new.bh = NULL; 3564 goto end_rename; 3565 } 3566 if (new.bh) { 3567 if (!new.inode) { 3568 brelse(new.bh); 3569 new.bh = NULL; 3570 } 3571 } 3572 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) 3573 ext4_alloc_da_blocks(old.inode); 3574 3575 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3576 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); 3577 if (!(flags & RENAME_WHITEOUT)) { 3578 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); 3579 if (IS_ERR(handle)) { 3580 retval = PTR_ERR(handle); 3581 handle = NULL; 3582 goto end_rename; 3583 } 3584 } else { 3585 whiteout = ext4_whiteout_for_rename(&old, credits, &handle); 3586 if (IS_ERR(whiteout)) { 3587 retval = PTR_ERR(whiteout); 3588 whiteout = NULL; 3589 goto end_rename; 3590 } 3591 } 3592 3593 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3594 ext4_handle_sync(handle); 3595 3596 if (S_ISDIR(old.inode->i_mode)) { 3597 if (new.inode) { 3598 retval = -ENOTEMPTY; 3599 if (!ext4_empty_dir(new.inode)) 3600 goto end_rename; 3601 } else { 3602 retval = -EMLINK; 3603 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) 3604 goto end_rename; 3605 } 3606 retval = ext4_rename_dir_prepare(handle, &old); 3607 if (retval) 3608 goto end_rename; 3609 } 3610 /* 3611 * If we're renaming a file within an inline_data dir and adding or 3612 * setting the new dirent causes a conversion from inline_data to 3613 * extents/blockmap, we need to force the dirent delete code to 3614 * re-read the directory, or else we end up trying to delete a dirent 3615 * from what is now the extent tree root (or a block map). 3616 */ 3617 force_reread = (new.dir->i_ino == old.dir->i_ino && 3618 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); 3619 3620 old_file_type = old.de->file_type; 3621 if (whiteout) { 3622 /* 3623 * Do this before adding a new entry, so the old entry is sure 3624 * to be still pointing to the valid old entry. 3625 */ 3626 retval = ext4_setent(handle, &old, whiteout->i_ino, 3627 EXT4_FT_CHRDEV); 3628 if (retval) 3629 goto end_rename; 3630 ext4_mark_inode_dirty(handle, whiteout); 3631 } 3632 if (!new.bh) { 3633 retval = ext4_add_entry(handle, new.dentry, old.inode); 3634 if (retval) 3635 goto end_rename; 3636 } else { 3637 retval = ext4_setent(handle, &new, 3638 old.inode->i_ino, old_file_type); 3639 if (retval) 3640 goto end_rename; 3641 } 3642 if (force_reread) 3643 force_reread = !ext4_test_inode_flag(new.dir, 3644 EXT4_INODE_INLINE_DATA); 3645 3646 /* 3647 * Like most other Unix systems, set the ctime for inodes on a 3648 * rename. 3649 */ 3650 old.inode->i_ctime = current_time(old.inode); 3651 ext4_mark_inode_dirty(handle, old.inode); 3652 3653 if (!whiteout) { 3654 /* 3655 * ok, that's it 3656 */ 3657 ext4_rename_delete(handle, &old, force_reread); 3658 } 3659 3660 if (new.inode) { 3661 ext4_dec_count(handle, new.inode); 3662 new.inode->i_ctime = current_time(new.inode); 3663 } 3664 old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir); 3665 ext4_update_dx_flag(old.dir); 3666 if (old.dir_bh) { 3667 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3668 if (retval) 3669 goto end_rename; 3670 3671 ext4_dec_count(handle, old.dir); 3672 if (new.inode) { 3673 /* checked ext4_empty_dir above, can't have another 3674 * parent, ext4_dec_count() won't work for many-linked 3675 * dirs */ 3676 clear_nlink(new.inode); 3677 } else { 3678 ext4_inc_count(handle, new.dir); 3679 ext4_update_dx_flag(new.dir); 3680 ext4_mark_inode_dirty(handle, new.dir); 3681 } 3682 } 3683 ext4_mark_inode_dirty(handle, old.dir); 3684 if (new.inode) { 3685 ext4_mark_inode_dirty(handle, new.inode); 3686 if (!new.inode->i_nlink) 3687 ext4_orphan_add(handle, new.inode); 3688 } 3689 retval = 0; 3690 3691 end_rename: 3692 brelse(old.dir_bh); 3693 brelse(old.bh); 3694 brelse(new.bh); 3695 if (whiteout) { 3696 if (retval) 3697 drop_nlink(whiteout); 3698 unlock_new_inode(whiteout); 3699 iput(whiteout); 3700 } 3701 if (handle) 3702 ext4_journal_stop(handle); 3703 return retval; 3704 } 3705 3706 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, 3707 struct inode *new_dir, struct dentry *new_dentry) 3708 { 3709 handle_t *handle = NULL; 3710 struct ext4_renament old = { 3711 .dir = old_dir, 3712 .dentry = old_dentry, 3713 .inode = d_inode(old_dentry), 3714 }; 3715 struct ext4_renament new = { 3716 .dir = new_dir, 3717 .dentry = new_dentry, 3718 .inode = d_inode(new_dentry), 3719 }; 3720 u8 new_file_type; 3721 int retval; 3722 struct timespec ctime; 3723 3724 if ((ext4_encrypted_inode(old_dir) && 3725 !fscrypt_has_encryption_key(old_dir)) || 3726 (ext4_encrypted_inode(new_dir) && 3727 !fscrypt_has_encryption_key(new_dir))) 3728 return -ENOKEY; 3729 3730 if ((ext4_encrypted_inode(old_dir) || 3731 ext4_encrypted_inode(new_dir)) && 3732 (old_dir != new_dir) && 3733 (!fscrypt_has_permitted_context(new_dir, old.inode) || 3734 !fscrypt_has_permitted_context(old_dir, new.inode))) 3735 return -EPERM; 3736 3737 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) && 3738 !projid_eq(EXT4_I(new_dir)->i_projid, 3739 EXT4_I(old_dentry->d_inode)->i_projid)) || 3740 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) && 3741 !projid_eq(EXT4_I(old_dir)->i_projid, 3742 EXT4_I(new_dentry->d_inode)->i_projid))) 3743 return -EXDEV; 3744 3745 retval = dquot_initialize(old.dir); 3746 if (retval) 3747 return retval; 3748 retval = dquot_initialize(new.dir); 3749 if (retval) 3750 return retval; 3751 3752 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, 3753 &old.de, &old.inlined); 3754 if (IS_ERR(old.bh)) 3755 return PTR_ERR(old.bh); 3756 /* 3757 * Check for inode number is _not_ due to possible IO errors. 3758 * We might rmdir the source, keep it as pwd of some process 3759 * and merrily kill the link to whatever was created under the 3760 * same name. Goodbye sticky bit ;-< 3761 */ 3762 retval = -ENOENT; 3763 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3764 goto end_rename; 3765 3766 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3767 &new.de, &new.inlined); 3768 if (IS_ERR(new.bh)) { 3769 retval = PTR_ERR(new.bh); 3770 new.bh = NULL; 3771 goto end_rename; 3772 } 3773 3774 /* RENAME_EXCHANGE case: old *and* new must both exist */ 3775 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) 3776 goto end_rename; 3777 3778 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, 3779 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3780 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); 3781 if (IS_ERR(handle)) { 3782 retval = PTR_ERR(handle); 3783 handle = NULL; 3784 goto end_rename; 3785 } 3786 3787 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3788 ext4_handle_sync(handle); 3789 3790 if (S_ISDIR(old.inode->i_mode)) { 3791 old.is_dir = true; 3792 retval = ext4_rename_dir_prepare(handle, &old); 3793 if (retval) 3794 goto end_rename; 3795 } 3796 if (S_ISDIR(new.inode->i_mode)) { 3797 new.is_dir = true; 3798 retval = ext4_rename_dir_prepare(handle, &new); 3799 if (retval) 3800 goto end_rename; 3801 } 3802 3803 /* 3804 * Other than the special case of overwriting a directory, parents' 3805 * nlink only needs to be modified if this is a cross directory rename. 3806 */ 3807 if (old.dir != new.dir && old.is_dir != new.is_dir) { 3808 old.dir_nlink_delta = old.is_dir ? -1 : 1; 3809 new.dir_nlink_delta = -old.dir_nlink_delta; 3810 retval = -EMLINK; 3811 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || 3812 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) 3813 goto end_rename; 3814 } 3815 3816 new_file_type = new.de->file_type; 3817 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); 3818 if (retval) 3819 goto end_rename; 3820 3821 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); 3822 if (retval) 3823 goto end_rename; 3824 3825 /* 3826 * Like most other Unix systems, set the ctime for inodes on a 3827 * rename. 3828 */ 3829 ctime = current_time(old.inode); 3830 old.inode->i_ctime = ctime; 3831 new.inode->i_ctime = ctime; 3832 ext4_mark_inode_dirty(handle, old.inode); 3833 ext4_mark_inode_dirty(handle, new.inode); 3834 3835 if (old.dir_bh) { 3836 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3837 if (retval) 3838 goto end_rename; 3839 } 3840 if (new.dir_bh) { 3841 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); 3842 if (retval) 3843 goto end_rename; 3844 } 3845 ext4_update_dir_count(handle, &old); 3846 ext4_update_dir_count(handle, &new); 3847 retval = 0; 3848 3849 end_rename: 3850 brelse(old.dir_bh); 3851 brelse(new.dir_bh); 3852 brelse(old.bh); 3853 brelse(new.bh); 3854 if (handle) 3855 ext4_journal_stop(handle); 3856 return retval; 3857 } 3858 3859 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, 3860 struct inode *new_dir, struct dentry *new_dentry, 3861 unsigned int flags) 3862 { 3863 if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb)))) 3864 return -EIO; 3865 3866 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 3867 return -EINVAL; 3868 3869 if (flags & RENAME_EXCHANGE) { 3870 return ext4_cross_rename(old_dir, old_dentry, 3871 new_dir, new_dentry); 3872 } 3873 3874 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 3875 } 3876 3877 /* 3878 * directories can handle most operations... 3879 */ 3880 const struct inode_operations ext4_dir_inode_operations = { 3881 .create = ext4_create, 3882 .lookup = ext4_lookup, 3883 .link = ext4_link, 3884 .unlink = ext4_unlink, 3885 .symlink = ext4_symlink, 3886 .mkdir = ext4_mkdir, 3887 .rmdir = ext4_rmdir, 3888 .mknod = ext4_mknod, 3889 .tmpfile = ext4_tmpfile, 3890 .rename = ext4_rename2, 3891 .setattr = ext4_setattr, 3892 .getattr = ext4_getattr, 3893 .listxattr = ext4_listxattr, 3894 .get_acl = ext4_get_acl, 3895 .set_acl = ext4_set_acl, 3896 .fiemap = ext4_fiemap, 3897 }; 3898 3899 const struct inode_operations ext4_special_inode_operations = { 3900 .setattr = ext4_setattr, 3901 .getattr = ext4_getattr, 3902 .listxattr = ext4_listxattr, 3903 .get_acl = ext4_get_acl, 3904 .set_acl = ext4_set_acl, 3905 }; 3906