1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/ext4/namei.c 4 * 5 * Copyright (C) 1992, 1993, 1994, 1995 6 * Remy Card (card@masi.ibp.fr) 7 * Laboratoire MASI - Institut Blaise Pascal 8 * Universite Pierre et Marie Curie (Paris VI) 9 * 10 * from 11 * 12 * linux/fs/minix/namei.c 13 * 14 * Copyright (C) 1991, 1992 Linus Torvalds 15 * 16 * Big-endian to little-endian byte-swapping/bitmaps by 17 * David S. Miller (davem@caip.rutgers.edu), 1995 18 * Directory entry file type support and forward compatibility hooks 19 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998 20 * Hash Tree Directory indexing (c) 21 * Daniel Phillips, 2001 22 * Hash Tree Directory indexing porting 23 * Christopher Li, 2002 24 * Hash Tree Directory indexing cleanup 25 * Theodore Ts'o, 2002 26 */ 27 28 #include <linux/fs.h> 29 #include <linux/pagemap.h> 30 #include <linux/time.h> 31 #include <linux/fcntl.h> 32 #include <linux/stat.h> 33 #include <linux/string.h> 34 #include <linux/quotaops.h> 35 #include <linux/buffer_head.h> 36 #include <linux/bio.h> 37 #include "ext4.h" 38 #include "ext4_jbd2.h" 39 40 #include "xattr.h" 41 #include "acl.h" 42 43 #include <trace/events/ext4.h> 44 /* 45 * define how far ahead to read directories while searching them. 46 */ 47 #define NAMEI_RA_CHUNKS 2 48 #define NAMEI_RA_BLOCKS 4 49 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) 50 51 static struct buffer_head *ext4_append(handle_t *handle, 52 struct inode *inode, 53 ext4_lblk_t *block) 54 { 55 struct buffer_head *bh; 56 int err; 57 58 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb && 59 ((inode->i_size >> 10) >= 60 EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) 61 return ERR_PTR(-ENOSPC); 62 63 *block = inode->i_size >> inode->i_sb->s_blocksize_bits; 64 65 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE); 66 if (IS_ERR(bh)) 67 return bh; 68 inode->i_size += inode->i_sb->s_blocksize; 69 EXT4_I(inode)->i_disksize = inode->i_size; 70 BUFFER_TRACE(bh, "get_write_access"); 71 err = ext4_journal_get_write_access(handle, bh); 72 if (err) { 73 brelse(bh); 74 ext4_std_error(inode->i_sb, err); 75 return ERR_PTR(err); 76 } 77 return bh; 78 } 79 80 static int ext4_dx_csum_verify(struct inode *inode, 81 struct ext4_dir_entry *dirent); 82 83 typedef enum { 84 EITHER, INDEX, DIRENT 85 } dirblock_type_t; 86 87 #define ext4_read_dirblock(inode, block, type) \ 88 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__) 89 90 static struct buffer_head *__ext4_read_dirblock(struct inode *inode, 91 ext4_lblk_t block, 92 dirblock_type_t type, 93 const char *func, 94 unsigned int line) 95 { 96 struct buffer_head *bh; 97 struct ext4_dir_entry *dirent; 98 int is_dx_block = 0; 99 100 bh = ext4_bread(NULL, inode, block, 0); 101 if (IS_ERR(bh)) { 102 __ext4_warning(inode->i_sb, func, line, 103 "inode #%lu: lblock %lu: comm %s: " 104 "error %ld reading directory block", 105 inode->i_ino, (unsigned long)block, 106 current->comm, PTR_ERR(bh)); 107 108 return bh; 109 } 110 if (!bh) { 111 ext4_error_inode(inode, func, line, block, 112 "Directory hole found"); 113 return ERR_PTR(-EFSCORRUPTED); 114 } 115 dirent = (struct ext4_dir_entry *) bh->b_data; 116 /* Determine whether or not we have an index block */ 117 if (is_dx(inode)) { 118 if (block == 0) 119 is_dx_block = 1; 120 else if (ext4_rec_len_from_disk(dirent->rec_len, 121 inode->i_sb->s_blocksize) == 122 inode->i_sb->s_blocksize) 123 is_dx_block = 1; 124 } 125 if (!is_dx_block && type == INDEX) { 126 ext4_error_inode(inode, func, line, block, 127 "directory leaf block found instead of index block"); 128 return ERR_PTR(-EFSCORRUPTED); 129 } 130 if (!ext4_has_metadata_csum(inode->i_sb) || 131 buffer_verified(bh)) 132 return bh; 133 134 /* 135 * An empty leaf block can get mistaken for a index block; for 136 * this reason, we can only check the index checksum when the 137 * caller is sure it should be an index block. 138 */ 139 if (is_dx_block && type == INDEX) { 140 if (ext4_dx_csum_verify(inode, dirent)) 141 set_buffer_verified(bh); 142 else { 143 ext4_error_inode(inode, func, line, block, 144 "Directory index failed checksum"); 145 brelse(bh); 146 return ERR_PTR(-EFSBADCRC); 147 } 148 } 149 if (!is_dx_block) { 150 if (ext4_dirent_csum_verify(inode, dirent)) 151 set_buffer_verified(bh); 152 else { 153 ext4_error_inode(inode, func, line, block, 154 "Directory block failed checksum"); 155 brelse(bh); 156 return ERR_PTR(-EFSBADCRC); 157 } 158 } 159 return bh; 160 } 161 162 #ifndef assert 163 #define assert(test) J_ASSERT(test) 164 #endif 165 166 #ifdef DX_DEBUG 167 #define dxtrace(command) command 168 #else 169 #define dxtrace(command) 170 #endif 171 172 struct fake_dirent 173 { 174 __le32 inode; 175 __le16 rec_len; 176 u8 name_len; 177 u8 file_type; 178 }; 179 180 struct dx_countlimit 181 { 182 __le16 limit; 183 __le16 count; 184 }; 185 186 struct dx_entry 187 { 188 __le32 hash; 189 __le32 block; 190 }; 191 192 /* 193 * dx_root_info is laid out so that if it should somehow get overlaid by a 194 * dirent the two low bits of the hash version will be zero. Therefore, the 195 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 196 */ 197 198 struct dx_root 199 { 200 struct fake_dirent dot; 201 char dot_name[4]; 202 struct fake_dirent dotdot; 203 char dotdot_name[4]; 204 struct dx_root_info 205 { 206 __le32 reserved_zero; 207 u8 hash_version; 208 u8 info_length; /* 8 */ 209 u8 indirect_levels; 210 u8 unused_flags; 211 } 212 info; 213 struct dx_entry entries[0]; 214 }; 215 216 struct dx_node 217 { 218 struct fake_dirent fake; 219 struct dx_entry entries[0]; 220 }; 221 222 223 struct dx_frame 224 { 225 struct buffer_head *bh; 226 struct dx_entry *entries; 227 struct dx_entry *at; 228 }; 229 230 struct dx_map_entry 231 { 232 u32 hash; 233 u16 offs; 234 u16 size; 235 }; 236 237 /* 238 * This goes at the end of each htree block. 239 */ 240 struct dx_tail { 241 u32 dt_reserved; 242 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */ 243 }; 244 245 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry); 246 static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value); 247 static inline unsigned dx_get_hash(struct dx_entry *entry); 248 static void dx_set_hash(struct dx_entry *entry, unsigned value); 249 static unsigned dx_get_count(struct dx_entry *entries); 250 static unsigned dx_get_limit(struct dx_entry *entries); 251 static void dx_set_count(struct dx_entry *entries, unsigned value); 252 static void dx_set_limit(struct dx_entry *entries, unsigned value); 253 static unsigned dx_root_limit(struct inode *dir, unsigned infosize); 254 static unsigned dx_node_limit(struct inode *dir); 255 static struct dx_frame *dx_probe(struct ext4_filename *fname, 256 struct inode *dir, 257 struct dx_hash_info *hinfo, 258 struct dx_frame *frame); 259 static void dx_release(struct dx_frame *frames); 260 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 261 unsigned blocksize, struct dx_hash_info *hinfo, 262 struct dx_map_entry map[]); 263 static void dx_sort_map(struct dx_map_entry *map, unsigned count); 264 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to, 265 struct dx_map_entry *offsets, int count, unsigned blocksize); 266 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize); 267 static void dx_insert_block(struct dx_frame *frame, 268 u32 hash, ext4_lblk_t block); 269 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 270 struct dx_frame *frame, 271 struct dx_frame *frames, 272 __u32 *start_hash); 273 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 274 struct ext4_filename *fname, 275 struct ext4_dir_entry_2 **res_dir); 276 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 277 struct inode *dir, struct inode *inode); 278 279 /* checksumming functions */ 280 void initialize_dirent_tail(struct ext4_dir_entry_tail *t, 281 unsigned int blocksize) 282 { 283 memset(t, 0, sizeof(struct ext4_dir_entry_tail)); 284 t->det_rec_len = ext4_rec_len_to_disk( 285 sizeof(struct ext4_dir_entry_tail), blocksize); 286 t->det_reserved_ft = EXT4_FT_DIR_CSUM; 287 } 288 289 /* Walk through a dirent block to find a checksum "dirent" at the tail */ 290 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode, 291 struct ext4_dir_entry *de) 292 { 293 struct ext4_dir_entry_tail *t; 294 295 #ifdef PARANOID 296 struct ext4_dir_entry *d, *top; 297 298 d = de; 299 top = (struct ext4_dir_entry *)(((void *)de) + 300 (EXT4_BLOCK_SIZE(inode->i_sb) - 301 sizeof(struct ext4_dir_entry_tail))); 302 while (d < top && d->rec_len) 303 d = (struct ext4_dir_entry *)(((void *)d) + 304 le16_to_cpu(d->rec_len)); 305 306 if (d != top) 307 return NULL; 308 309 t = (struct ext4_dir_entry_tail *)d; 310 #else 311 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb)); 312 #endif 313 314 if (t->det_reserved_zero1 || 315 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) || 316 t->det_reserved_zero2 || 317 t->det_reserved_ft != EXT4_FT_DIR_CSUM) 318 return NULL; 319 320 return t; 321 } 322 323 static __le32 ext4_dirent_csum(struct inode *inode, 324 struct ext4_dir_entry *dirent, int size) 325 { 326 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 327 struct ext4_inode_info *ei = EXT4_I(inode); 328 __u32 csum; 329 330 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 331 return cpu_to_le32(csum); 332 } 333 334 #define warn_no_space_for_csum(inode) \ 335 __warn_no_space_for_csum((inode), __func__, __LINE__) 336 337 static void __warn_no_space_for_csum(struct inode *inode, const char *func, 338 unsigned int line) 339 { 340 __ext4_warning_inode(inode, func, line, 341 "No space for directory leaf checksum. Please run e2fsck -D."); 342 } 343 344 int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent) 345 { 346 struct ext4_dir_entry_tail *t; 347 348 if (!ext4_has_metadata_csum(inode->i_sb)) 349 return 1; 350 351 t = get_dirent_tail(inode, dirent); 352 if (!t) { 353 warn_no_space_for_csum(inode); 354 return 0; 355 } 356 357 if (t->det_checksum != ext4_dirent_csum(inode, dirent, 358 (void *)t - (void *)dirent)) 359 return 0; 360 361 return 1; 362 } 363 364 static void ext4_dirent_csum_set(struct inode *inode, 365 struct ext4_dir_entry *dirent) 366 { 367 struct ext4_dir_entry_tail *t; 368 369 if (!ext4_has_metadata_csum(inode->i_sb)) 370 return; 371 372 t = get_dirent_tail(inode, dirent); 373 if (!t) { 374 warn_no_space_for_csum(inode); 375 return; 376 } 377 378 t->det_checksum = ext4_dirent_csum(inode, dirent, 379 (void *)t - (void *)dirent); 380 } 381 382 int ext4_handle_dirty_dirent_node(handle_t *handle, 383 struct inode *inode, 384 struct buffer_head *bh) 385 { 386 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 387 return ext4_handle_dirty_metadata(handle, inode, bh); 388 } 389 390 static struct dx_countlimit *get_dx_countlimit(struct inode *inode, 391 struct ext4_dir_entry *dirent, 392 int *offset) 393 { 394 struct ext4_dir_entry *dp; 395 struct dx_root_info *root; 396 int count_offset; 397 398 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb)) 399 count_offset = 8; 400 else if (le16_to_cpu(dirent->rec_len) == 12) { 401 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12); 402 if (le16_to_cpu(dp->rec_len) != 403 EXT4_BLOCK_SIZE(inode->i_sb) - 12) 404 return NULL; 405 root = (struct dx_root_info *)(((void *)dp + 12)); 406 if (root->reserved_zero || 407 root->info_length != sizeof(struct dx_root_info)) 408 return NULL; 409 count_offset = 32; 410 } else 411 return NULL; 412 413 if (offset) 414 *offset = count_offset; 415 return (struct dx_countlimit *)(((void *)dirent) + count_offset); 416 } 417 418 static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent, 419 int count_offset, int count, struct dx_tail *t) 420 { 421 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 422 struct ext4_inode_info *ei = EXT4_I(inode); 423 __u32 csum; 424 int size; 425 __u32 dummy_csum = 0; 426 int offset = offsetof(struct dx_tail, dt_checksum); 427 428 size = count_offset + (count * sizeof(struct dx_entry)); 429 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 430 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset); 431 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); 432 433 return cpu_to_le32(csum); 434 } 435 436 static int ext4_dx_csum_verify(struct inode *inode, 437 struct ext4_dir_entry *dirent) 438 { 439 struct dx_countlimit *c; 440 struct dx_tail *t; 441 int count_offset, limit, count; 442 443 if (!ext4_has_metadata_csum(inode->i_sb)) 444 return 1; 445 446 c = get_dx_countlimit(inode, dirent, &count_offset); 447 if (!c) { 448 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 449 return 0; 450 } 451 limit = le16_to_cpu(c->limit); 452 count = le16_to_cpu(c->count); 453 if (count_offset + (limit * sizeof(struct dx_entry)) > 454 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 455 warn_no_space_for_csum(inode); 456 return 0; 457 } 458 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 459 460 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset, 461 count, t)) 462 return 0; 463 return 1; 464 } 465 466 static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent) 467 { 468 struct dx_countlimit *c; 469 struct dx_tail *t; 470 int count_offset, limit, count; 471 472 if (!ext4_has_metadata_csum(inode->i_sb)) 473 return; 474 475 c = get_dx_countlimit(inode, dirent, &count_offset); 476 if (!c) { 477 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 478 return; 479 } 480 limit = le16_to_cpu(c->limit); 481 count = le16_to_cpu(c->count); 482 if (count_offset + (limit * sizeof(struct dx_entry)) > 483 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 484 warn_no_space_for_csum(inode); 485 return; 486 } 487 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 488 489 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t); 490 } 491 492 static inline int ext4_handle_dirty_dx_node(handle_t *handle, 493 struct inode *inode, 494 struct buffer_head *bh) 495 { 496 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 497 return ext4_handle_dirty_metadata(handle, inode, bh); 498 } 499 500 /* 501 * p is at least 6 bytes before the end of page 502 */ 503 static inline struct ext4_dir_entry_2 * 504 ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize) 505 { 506 return (struct ext4_dir_entry_2 *)((char *)p + 507 ext4_rec_len_from_disk(p->rec_len, blocksize)); 508 } 509 510 /* 511 * Future: use high four bits of block for coalesce-on-delete flags 512 * Mask them off for now. 513 */ 514 515 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry) 516 { 517 return le32_to_cpu(entry->block) & 0x0fffffff; 518 } 519 520 static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value) 521 { 522 entry->block = cpu_to_le32(value); 523 } 524 525 static inline unsigned dx_get_hash(struct dx_entry *entry) 526 { 527 return le32_to_cpu(entry->hash); 528 } 529 530 static inline void dx_set_hash(struct dx_entry *entry, unsigned value) 531 { 532 entry->hash = cpu_to_le32(value); 533 } 534 535 static inline unsigned dx_get_count(struct dx_entry *entries) 536 { 537 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 538 } 539 540 static inline unsigned dx_get_limit(struct dx_entry *entries) 541 { 542 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 543 } 544 545 static inline void dx_set_count(struct dx_entry *entries, unsigned value) 546 { 547 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 548 } 549 550 static inline void dx_set_limit(struct dx_entry *entries, unsigned value) 551 { 552 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 553 } 554 555 static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize) 556 { 557 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) - 558 EXT4_DIR_REC_LEN(2) - infosize; 559 560 if (ext4_has_metadata_csum(dir->i_sb)) 561 entry_space -= sizeof(struct dx_tail); 562 return entry_space / sizeof(struct dx_entry); 563 } 564 565 static inline unsigned dx_node_limit(struct inode *dir) 566 { 567 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0); 568 569 if (ext4_has_metadata_csum(dir->i_sb)) 570 entry_space -= sizeof(struct dx_tail); 571 return entry_space / sizeof(struct dx_entry); 572 } 573 574 /* 575 * Debug 576 */ 577 #ifdef DX_DEBUG 578 static void dx_show_index(char * label, struct dx_entry *entries) 579 { 580 int i, n = dx_get_count (entries); 581 printk(KERN_DEBUG "%s index", label); 582 for (i = 0; i < n; i++) { 583 printk(KERN_CONT " %x->%lu", 584 i ? dx_get_hash(entries + i) : 0, 585 (unsigned long)dx_get_block(entries + i)); 586 } 587 printk(KERN_CONT "\n"); 588 } 589 590 struct stats 591 { 592 unsigned names; 593 unsigned space; 594 unsigned bcount; 595 }; 596 597 static struct stats dx_show_leaf(struct inode *dir, 598 struct dx_hash_info *hinfo, 599 struct ext4_dir_entry_2 *de, 600 int size, int show_names) 601 { 602 unsigned names = 0, space = 0; 603 char *base = (char *) de; 604 struct dx_hash_info h = *hinfo; 605 606 printk("names: "); 607 while ((char *) de < base + size) 608 { 609 if (de->inode) 610 { 611 if (show_names) 612 { 613 #ifdef CONFIG_EXT4_FS_ENCRYPTION 614 int len; 615 char *name; 616 struct fscrypt_str fname_crypto_str = 617 FSTR_INIT(NULL, 0); 618 int res = 0; 619 620 name = de->name; 621 len = de->name_len; 622 if (ext4_encrypted_inode(dir)) 623 res = fscrypt_get_encryption_info(dir); 624 if (res) { 625 printk(KERN_WARNING "Error setting up" 626 " fname crypto: %d\n", res); 627 } 628 if (!fscrypt_has_encryption_key(dir)) { 629 /* Directory is not encrypted */ 630 ext4fs_dirhash(de->name, 631 de->name_len, &h); 632 printk("%*.s:(U)%x.%u ", len, 633 name, h.hash, 634 (unsigned) ((char *) de 635 - base)); 636 } else { 637 struct fscrypt_str de_name = 638 FSTR_INIT(name, len); 639 640 /* Directory is encrypted */ 641 res = fscrypt_fname_alloc_buffer( 642 dir, len, 643 &fname_crypto_str); 644 if (res) 645 printk(KERN_WARNING "Error " 646 "allocating crypto " 647 "buffer--skipping " 648 "crypto\n"); 649 res = fscrypt_fname_disk_to_usr(dir, 650 0, 0, &de_name, 651 &fname_crypto_str); 652 if (res) { 653 printk(KERN_WARNING "Error " 654 "converting filename " 655 "from disk to usr" 656 "\n"); 657 name = "??"; 658 len = 2; 659 } else { 660 name = fname_crypto_str.name; 661 len = fname_crypto_str.len; 662 } 663 ext4fs_dirhash(de->name, de->name_len, 664 &h); 665 printk("%*.s:(E)%x.%u ", len, name, 666 h.hash, (unsigned) ((char *) de 667 - base)); 668 fscrypt_fname_free_buffer( 669 &fname_crypto_str); 670 } 671 #else 672 int len = de->name_len; 673 char *name = de->name; 674 ext4fs_dirhash(de->name, de->name_len, &h); 675 printk("%*.s:%x.%u ", len, name, h.hash, 676 (unsigned) ((char *) de - base)); 677 #endif 678 } 679 space += EXT4_DIR_REC_LEN(de->name_len); 680 names++; 681 } 682 de = ext4_next_entry(de, size); 683 } 684 printk(KERN_CONT "(%i)\n", names); 685 return (struct stats) { names, space, 1 }; 686 } 687 688 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 689 struct dx_entry *entries, int levels) 690 { 691 unsigned blocksize = dir->i_sb->s_blocksize; 692 unsigned count = dx_get_count(entries), names = 0, space = 0, i; 693 unsigned bcount = 0; 694 struct buffer_head *bh; 695 printk("%i indexed blocks...\n", count); 696 for (i = 0; i < count; i++, entries++) 697 { 698 ext4_lblk_t block = dx_get_block(entries); 699 ext4_lblk_t hash = i ? dx_get_hash(entries): 0; 700 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 701 struct stats stats; 702 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 703 bh = ext4_bread(NULL,dir, block, 0); 704 if (!bh || IS_ERR(bh)) 705 continue; 706 stats = levels? 707 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 708 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) 709 bh->b_data, blocksize, 0); 710 names += stats.names; 711 space += stats.space; 712 bcount += stats.bcount; 713 brelse(bh); 714 } 715 if (bcount) 716 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n", 717 levels ? "" : " ", names, space/bcount, 718 (space/bcount)*100/blocksize); 719 return (struct stats) { names, space, bcount}; 720 } 721 #endif /* DX_DEBUG */ 722 723 /* 724 * Probe for a directory leaf block to search. 725 * 726 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 727 * error in the directory index, and the caller should fall back to 728 * searching the directory normally. The callers of dx_probe **MUST** 729 * check for this error code, and make sure it never gets reflected 730 * back to userspace. 731 */ 732 static struct dx_frame * 733 dx_probe(struct ext4_filename *fname, struct inode *dir, 734 struct dx_hash_info *hinfo, struct dx_frame *frame_in) 735 { 736 unsigned count, indirect; 737 struct dx_entry *at, *entries, *p, *q, *m; 738 struct dx_root *root; 739 struct dx_frame *frame = frame_in; 740 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR); 741 u32 hash; 742 743 memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0])); 744 frame->bh = ext4_read_dirblock(dir, 0, INDEX); 745 if (IS_ERR(frame->bh)) 746 return (struct dx_frame *) frame->bh; 747 748 root = (struct dx_root *) frame->bh->b_data; 749 if (root->info.hash_version != DX_HASH_TEA && 750 root->info.hash_version != DX_HASH_HALF_MD4 && 751 root->info.hash_version != DX_HASH_LEGACY) { 752 ext4_warning_inode(dir, "Unrecognised inode hash code %u", 753 root->info.hash_version); 754 goto fail; 755 } 756 if (fname) 757 hinfo = &fname->hinfo; 758 hinfo->hash_version = root->info.hash_version; 759 if (hinfo->hash_version <= DX_HASH_TEA) 760 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 761 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; 762 if (fname && fname_name(fname)) 763 ext4fs_dirhash(fname_name(fname), fname_len(fname), hinfo); 764 hash = hinfo->hash; 765 766 if (root->info.unused_flags & 1) { 767 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x", 768 root->info.unused_flags); 769 goto fail; 770 } 771 772 indirect = root->info.indirect_levels; 773 if (indirect >= ext4_dir_htree_level(dir->i_sb)) { 774 ext4_warning(dir->i_sb, 775 "Directory (ino: %lu) htree depth %#06x exceed" 776 "supported value", dir->i_ino, 777 ext4_dir_htree_level(dir->i_sb)); 778 if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) { 779 ext4_warning(dir->i_sb, "Enable large directory " 780 "feature to access it"); 781 } 782 goto fail; 783 } 784 785 entries = (struct dx_entry *)(((char *)&root->info) + 786 root->info.info_length); 787 788 if (dx_get_limit(entries) != dx_root_limit(dir, 789 root->info.info_length)) { 790 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u", 791 dx_get_limit(entries), 792 dx_root_limit(dir, root->info.info_length)); 793 goto fail; 794 } 795 796 dxtrace(printk("Look up %x", hash)); 797 while (1) { 798 count = dx_get_count(entries); 799 if (!count || count > dx_get_limit(entries)) { 800 ext4_warning_inode(dir, 801 "dx entry: count %u beyond limit %u", 802 count, dx_get_limit(entries)); 803 goto fail; 804 } 805 806 p = entries + 1; 807 q = entries + count - 1; 808 while (p <= q) { 809 m = p + (q - p) / 2; 810 dxtrace(printk(KERN_CONT ".")); 811 if (dx_get_hash(m) > hash) 812 q = m - 1; 813 else 814 p = m + 1; 815 } 816 817 if (0) { // linear search cross check 818 unsigned n = count - 1; 819 at = entries; 820 while (n--) 821 { 822 dxtrace(printk(KERN_CONT ",")); 823 if (dx_get_hash(++at) > hash) 824 { 825 at--; 826 break; 827 } 828 } 829 assert (at == p - 1); 830 } 831 832 at = p - 1; 833 dxtrace(printk(KERN_CONT " %x->%u\n", 834 at == entries ? 0 : dx_get_hash(at), 835 dx_get_block(at))); 836 frame->entries = entries; 837 frame->at = at; 838 if (!indirect--) 839 return frame; 840 frame++; 841 frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX); 842 if (IS_ERR(frame->bh)) { 843 ret_err = (struct dx_frame *) frame->bh; 844 frame->bh = NULL; 845 goto fail; 846 } 847 entries = ((struct dx_node *) frame->bh->b_data)->entries; 848 849 if (dx_get_limit(entries) != dx_node_limit(dir)) { 850 ext4_warning_inode(dir, 851 "dx entry: limit %u != node limit %u", 852 dx_get_limit(entries), dx_node_limit(dir)); 853 goto fail; 854 } 855 } 856 fail: 857 while (frame >= frame_in) { 858 brelse(frame->bh); 859 frame--; 860 } 861 862 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR)) 863 ext4_warning_inode(dir, 864 "Corrupt directory, running e2fsck is recommended"); 865 return ret_err; 866 } 867 868 static void dx_release(struct dx_frame *frames) 869 { 870 struct dx_root_info *info; 871 int i; 872 873 if (frames[0].bh == NULL) 874 return; 875 876 info = &((struct dx_root *)frames[0].bh->b_data)->info; 877 for (i = 0; i <= info->indirect_levels; i++) { 878 if (frames[i].bh == NULL) 879 break; 880 brelse(frames[i].bh); 881 frames[i].bh = NULL; 882 } 883 } 884 885 /* 886 * This function increments the frame pointer to search the next leaf 887 * block, and reads in the necessary intervening nodes if the search 888 * should be necessary. Whether or not the search is necessary is 889 * controlled by the hash parameter. If the hash value is even, then 890 * the search is only continued if the next block starts with that 891 * hash value. This is used if we are searching for a specific file. 892 * 893 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 894 * 895 * This function returns 1 if the caller should continue to search, 896 * or 0 if it should not. If there is an error reading one of the 897 * index blocks, it will a negative error code. 898 * 899 * If start_hash is non-null, it will be filled in with the starting 900 * hash of the next page. 901 */ 902 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 903 struct dx_frame *frame, 904 struct dx_frame *frames, 905 __u32 *start_hash) 906 { 907 struct dx_frame *p; 908 struct buffer_head *bh; 909 int num_frames = 0; 910 __u32 bhash; 911 912 p = frame; 913 /* 914 * Find the next leaf page by incrementing the frame pointer. 915 * If we run out of entries in the interior node, loop around and 916 * increment pointer in the parent node. When we break out of 917 * this loop, num_frames indicates the number of interior 918 * nodes need to be read. 919 */ 920 while (1) { 921 if (++(p->at) < p->entries + dx_get_count(p->entries)) 922 break; 923 if (p == frames) 924 return 0; 925 num_frames++; 926 p--; 927 } 928 929 /* 930 * If the hash is 1, then continue only if the next page has a 931 * continuation hash of any value. This is used for readdir 932 * handling. Otherwise, check to see if the hash matches the 933 * desired contiuation hash. If it doesn't, return since 934 * there's no point to read in the successive index pages. 935 */ 936 bhash = dx_get_hash(p->at); 937 if (start_hash) 938 *start_hash = bhash; 939 if ((hash & 1) == 0) { 940 if ((bhash & ~1) != hash) 941 return 0; 942 } 943 /* 944 * If the hash is HASH_NB_ALWAYS, we always go to the next 945 * block so no check is necessary 946 */ 947 while (num_frames--) { 948 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX); 949 if (IS_ERR(bh)) 950 return PTR_ERR(bh); 951 p++; 952 brelse(p->bh); 953 p->bh = bh; 954 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 955 } 956 return 1; 957 } 958 959 960 /* 961 * This function fills a red-black tree with information from a 962 * directory block. It returns the number directory entries loaded 963 * into the tree. If there is an error it is returned in err. 964 */ 965 static int htree_dirblock_to_tree(struct file *dir_file, 966 struct inode *dir, ext4_lblk_t block, 967 struct dx_hash_info *hinfo, 968 __u32 start_hash, __u32 start_minor_hash) 969 { 970 struct buffer_head *bh; 971 struct ext4_dir_entry_2 *de, *top; 972 int err = 0, count = 0; 973 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str; 974 975 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", 976 (unsigned long)block)); 977 bh = ext4_read_dirblock(dir, block, DIRENT); 978 if (IS_ERR(bh)) 979 return PTR_ERR(bh); 980 981 de = (struct ext4_dir_entry_2 *) bh->b_data; 982 top = (struct ext4_dir_entry_2 *) ((char *) de + 983 dir->i_sb->s_blocksize - 984 EXT4_DIR_REC_LEN(0)); 985 #ifdef CONFIG_EXT4_FS_ENCRYPTION 986 /* Check if the directory is encrypted */ 987 if (ext4_encrypted_inode(dir)) { 988 err = fscrypt_get_encryption_info(dir); 989 if (err < 0) { 990 brelse(bh); 991 return err; 992 } 993 err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN, 994 &fname_crypto_str); 995 if (err < 0) { 996 brelse(bh); 997 return err; 998 } 999 } 1000 #endif 1001 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { 1002 if (ext4_check_dir_entry(dir, NULL, de, bh, 1003 bh->b_data, bh->b_size, 1004 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb)) 1005 + ((char *)de - bh->b_data))) { 1006 /* silently ignore the rest of the block */ 1007 break; 1008 } 1009 ext4fs_dirhash(de->name, de->name_len, hinfo); 1010 if ((hinfo->hash < start_hash) || 1011 ((hinfo->hash == start_hash) && 1012 (hinfo->minor_hash < start_minor_hash))) 1013 continue; 1014 if (de->inode == 0) 1015 continue; 1016 if (!ext4_encrypted_inode(dir)) { 1017 tmp_str.name = de->name; 1018 tmp_str.len = de->name_len; 1019 err = ext4_htree_store_dirent(dir_file, 1020 hinfo->hash, hinfo->minor_hash, de, 1021 &tmp_str); 1022 } else { 1023 int save_len = fname_crypto_str.len; 1024 struct fscrypt_str de_name = FSTR_INIT(de->name, 1025 de->name_len); 1026 1027 /* Directory is encrypted */ 1028 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash, 1029 hinfo->minor_hash, &de_name, 1030 &fname_crypto_str); 1031 if (err) { 1032 count = err; 1033 goto errout; 1034 } 1035 err = ext4_htree_store_dirent(dir_file, 1036 hinfo->hash, hinfo->minor_hash, de, 1037 &fname_crypto_str); 1038 fname_crypto_str.len = save_len; 1039 } 1040 if (err != 0) { 1041 count = err; 1042 goto errout; 1043 } 1044 count++; 1045 } 1046 errout: 1047 brelse(bh); 1048 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1049 fscrypt_fname_free_buffer(&fname_crypto_str); 1050 #endif 1051 return count; 1052 } 1053 1054 1055 /* 1056 * This function fills a red-black tree with information from a 1057 * directory. We start scanning the directory in hash order, starting 1058 * at start_hash and start_minor_hash. 1059 * 1060 * This function returns the number of entries inserted into the tree, 1061 * or a negative error code. 1062 */ 1063 int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, 1064 __u32 start_minor_hash, __u32 *next_hash) 1065 { 1066 struct dx_hash_info hinfo; 1067 struct ext4_dir_entry_2 *de; 1068 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1069 struct inode *dir; 1070 ext4_lblk_t block; 1071 int count = 0; 1072 int ret, err; 1073 __u32 hashval; 1074 struct fscrypt_str tmp_str; 1075 1076 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n", 1077 start_hash, start_minor_hash)); 1078 dir = file_inode(dir_file); 1079 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) { 1080 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1081 if (hinfo.hash_version <= DX_HASH_TEA) 1082 hinfo.hash_version += 1083 EXT4_SB(dir->i_sb)->s_hash_unsigned; 1084 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1085 if (ext4_has_inline_data(dir)) { 1086 int has_inline_data = 1; 1087 count = htree_inlinedir_to_tree(dir_file, dir, 0, 1088 &hinfo, start_hash, 1089 start_minor_hash, 1090 &has_inline_data); 1091 if (has_inline_data) { 1092 *next_hash = ~0; 1093 return count; 1094 } 1095 } 1096 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 1097 start_hash, start_minor_hash); 1098 *next_hash = ~0; 1099 return count; 1100 } 1101 hinfo.hash = start_hash; 1102 hinfo.minor_hash = 0; 1103 frame = dx_probe(NULL, dir, &hinfo, frames); 1104 if (IS_ERR(frame)) 1105 return PTR_ERR(frame); 1106 1107 /* Add '.' and '..' from the htree header */ 1108 if (!start_hash && !start_minor_hash) { 1109 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1110 tmp_str.name = de->name; 1111 tmp_str.len = de->name_len; 1112 err = ext4_htree_store_dirent(dir_file, 0, 0, 1113 de, &tmp_str); 1114 if (err != 0) 1115 goto errout; 1116 count++; 1117 } 1118 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 1119 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1120 de = ext4_next_entry(de, dir->i_sb->s_blocksize); 1121 tmp_str.name = de->name; 1122 tmp_str.len = de->name_len; 1123 err = ext4_htree_store_dirent(dir_file, 2, 0, 1124 de, &tmp_str); 1125 if (err != 0) 1126 goto errout; 1127 count++; 1128 } 1129 1130 while (1) { 1131 if (fatal_signal_pending(current)) { 1132 err = -ERESTARTSYS; 1133 goto errout; 1134 } 1135 cond_resched(); 1136 block = dx_get_block(frame->at); 1137 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 1138 start_hash, start_minor_hash); 1139 if (ret < 0) { 1140 err = ret; 1141 goto errout; 1142 } 1143 count += ret; 1144 hashval = ~0; 1145 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS, 1146 frame, frames, &hashval); 1147 *next_hash = hashval; 1148 if (ret < 0) { 1149 err = ret; 1150 goto errout; 1151 } 1152 /* 1153 * Stop if: (a) there are no more entries, or 1154 * (b) we have inserted at least one entry and the 1155 * next hash value is not a continuation 1156 */ 1157 if ((ret == 0) || 1158 (count && ((hashval & 1) == 0))) 1159 break; 1160 } 1161 dx_release(frames); 1162 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, " 1163 "next hash: %x\n", count, *next_hash)); 1164 return count; 1165 errout: 1166 dx_release(frames); 1167 return (err); 1168 } 1169 1170 static inline int search_dirblock(struct buffer_head *bh, 1171 struct inode *dir, 1172 struct ext4_filename *fname, 1173 unsigned int offset, 1174 struct ext4_dir_entry_2 **res_dir) 1175 { 1176 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir, 1177 fname, offset, res_dir); 1178 } 1179 1180 /* 1181 * Directory block splitting, compacting 1182 */ 1183 1184 /* 1185 * Create map of hash values, offsets, and sizes, stored at end of block. 1186 * Returns number of entries mapped. 1187 */ 1188 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 1189 unsigned blocksize, struct dx_hash_info *hinfo, 1190 struct dx_map_entry *map_tail) 1191 { 1192 int count = 0; 1193 char *base = (char *) de; 1194 struct dx_hash_info h = *hinfo; 1195 1196 while ((char *) de < base + blocksize) { 1197 if (de->name_len && de->inode) { 1198 ext4fs_dirhash(de->name, de->name_len, &h); 1199 map_tail--; 1200 map_tail->hash = h.hash; 1201 map_tail->offs = ((char *) de - base)>>2; 1202 map_tail->size = le16_to_cpu(de->rec_len); 1203 count++; 1204 cond_resched(); 1205 } 1206 /* XXX: do we need to check rec_len == 0 case? -Chris */ 1207 de = ext4_next_entry(de, blocksize); 1208 } 1209 return count; 1210 } 1211 1212 /* Sort map by hash value */ 1213 static void dx_sort_map (struct dx_map_entry *map, unsigned count) 1214 { 1215 struct dx_map_entry *p, *q, *top = map + count - 1; 1216 int more; 1217 /* Combsort until bubble sort doesn't suck */ 1218 while (count > 2) { 1219 count = count*10/13; 1220 if (count - 9 < 2) /* 9, 10 -> 11 */ 1221 count = 11; 1222 for (p = top, q = p - count; q >= map; p--, q--) 1223 if (p->hash < q->hash) 1224 swap(*p, *q); 1225 } 1226 /* Garden variety bubble sort */ 1227 do { 1228 more = 0; 1229 q = top; 1230 while (q-- > map) { 1231 if (q[1].hash >= q[0].hash) 1232 continue; 1233 swap(*(q+1), *q); 1234 more = 1; 1235 } 1236 } while(more); 1237 } 1238 1239 static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) 1240 { 1241 struct dx_entry *entries = frame->entries; 1242 struct dx_entry *old = frame->at, *new = old + 1; 1243 int count = dx_get_count(entries); 1244 1245 assert(count < dx_get_limit(entries)); 1246 assert(old < entries + count); 1247 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 1248 dx_set_hash(new, hash); 1249 dx_set_block(new, block); 1250 dx_set_count(entries, count + 1); 1251 } 1252 1253 /* 1254 * Test whether a directory entry matches the filename being searched for. 1255 * 1256 * Return: %true if the directory entry matches, otherwise %false. 1257 */ 1258 static inline bool ext4_match(const struct ext4_filename *fname, 1259 const struct ext4_dir_entry_2 *de) 1260 { 1261 struct fscrypt_name f; 1262 1263 if (!de->inode) 1264 return false; 1265 1266 f.usr_fname = fname->usr_fname; 1267 f.disk_name = fname->disk_name; 1268 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1269 f.crypto_buf = fname->crypto_buf; 1270 #endif 1271 return fscrypt_match_name(&f, de->name, de->name_len); 1272 } 1273 1274 /* 1275 * Returns 0 if not found, -1 on failure, and 1 on success 1276 */ 1277 int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, 1278 struct inode *dir, struct ext4_filename *fname, 1279 unsigned int offset, struct ext4_dir_entry_2 **res_dir) 1280 { 1281 struct ext4_dir_entry_2 * de; 1282 char * dlimit; 1283 int de_len; 1284 1285 de = (struct ext4_dir_entry_2 *)search_buf; 1286 dlimit = search_buf + buf_size; 1287 while ((char *) de < dlimit) { 1288 /* this code is executed quadratically often */ 1289 /* do minimal checking `by hand' */ 1290 if ((char *) de + de->name_len <= dlimit && 1291 ext4_match(fname, de)) { 1292 /* found a match - just to be sure, do 1293 * a full check */ 1294 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, 1295 bh->b_size, offset)) 1296 return -1; 1297 *res_dir = de; 1298 return 1; 1299 } 1300 /* prevent looping on a bad block */ 1301 de_len = ext4_rec_len_from_disk(de->rec_len, 1302 dir->i_sb->s_blocksize); 1303 if (de_len <= 0) 1304 return -1; 1305 offset += de_len; 1306 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); 1307 } 1308 return 0; 1309 } 1310 1311 static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block, 1312 struct ext4_dir_entry *de) 1313 { 1314 struct super_block *sb = dir->i_sb; 1315 1316 if (!is_dx(dir)) 1317 return 0; 1318 if (block == 0) 1319 return 1; 1320 if (de->inode == 0 && 1321 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) == 1322 sb->s_blocksize) 1323 return 1; 1324 return 0; 1325 } 1326 1327 /* 1328 * ext4_find_entry() 1329 * 1330 * finds an entry in the specified directory with the wanted name. It 1331 * returns the cache buffer in which the entry was found, and the entry 1332 * itself (as a parameter - res_dir). It does NOT read the inode of the 1333 * entry - you'll have to do that yourself if you want to. 1334 * 1335 * The returned buffer_head has ->b_count elevated. The caller is expected 1336 * to brelse() it when appropriate. 1337 */ 1338 static struct buffer_head * ext4_find_entry (struct inode *dir, 1339 const struct qstr *d_name, 1340 struct ext4_dir_entry_2 **res_dir, 1341 int *inlined) 1342 { 1343 struct super_block *sb; 1344 struct buffer_head *bh_use[NAMEI_RA_SIZE]; 1345 struct buffer_head *bh, *ret = NULL; 1346 ext4_lblk_t start, block; 1347 const u8 *name = d_name->name; 1348 size_t ra_max = 0; /* Number of bh's in the readahead 1349 buffer, bh_use[] */ 1350 size_t ra_ptr = 0; /* Current index into readahead 1351 buffer */ 1352 ext4_lblk_t nblocks; 1353 int i, namelen, retval; 1354 struct ext4_filename fname; 1355 1356 *res_dir = NULL; 1357 sb = dir->i_sb; 1358 namelen = d_name->len; 1359 if (namelen > EXT4_NAME_LEN) 1360 return NULL; 1361 1362 retval = ext4_fname_setup_filename(dir, d_name, 1, &fname); 1363 if (retval == -ENOENT) 1364 return NULL; 1365 if (retval) 1366 return ERR_PTR(retval); 1367 1368 if (ext4_has_inline_data(dir)) { 1369 int has_inline_data = 1; 1370 ret = ext4_find_inline_entry(dir, &fname, res_dir, 1371 &has_inline_data); 1372 if (has_inline_data) { 1373 if (inlined) 1374 *inlined = 1; 1375 goto cleanup_and_exit; 1376 } 1377 } 1378 1379 if ((namelen <= 2) && (name[0] == '.') && 1380 (name[1] == '.' || name[1] == '\0')) { 1381 /* 1382 * "." or ".." will only be in the first block 1383 * NFS may look up ".."; "." should be handled by the VFS 1384 */ 1385 block = start = 0; 1386 nblocks = 1; 1387 goto restart; 1388 } 1389 if (is_dx(dir)) { 1390 ret = ext4_dx_find_entry(dir, &fname, res_dir); 1391 /* 1392 * On success, or if the error was file not found, 1393 * return. Otherwise, fall back to doing a search the 1394 * old fashioned way. 1395 */ 1396 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) 1397 goto cleanup_and_exit; 1398 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " 1399 "falling back\n")); 1400 } 1401 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1402 start = EXT4_I(dir)->i_dir_start_lookup; 1403 if (start >= nblocks) 1404 start = 0; 1405 block = start; 1406 restart: 1407 do { 1408 /* 1409 * We deal with the read-ahead logic here. 1410 */ 1411 if (ra_ptr >= ra_max) { 1412 /* Refill the readahead buffer */ 1413 ra_ptr = 0; 1414 if (block < start) 1415 ra_max = start - block; 1416 else 1417 ra_max = nblocks - block; 1418 ra_max = min(ra_max, ARRAY_SIZE(bh_use)); 1419 retval = ext4_bread_batch(dir, block, ra_max, 1420 false /* wait */, bh_use); 1421 if (retval) { 1422 ret = ERR_PTR(retval); 1423 ra_max = 0; 1424 goto cleanup_and_exit; 1425 } 1426 } 1427 if ((bh = bh_use[ra_ptr++]) == NULL) 1428 goto next; 1429 wait_on_buffer(bh); 1430 if (!buffer_uptodate(bh)) { 1431 EXT4_ERROR_INODE(dir, "reading directory lblock %lu", 1432 (unsigned long) block); 1433 brelse(bh); 1434 ret = ERR_PTR(-EIO); 1435 goto cleanup_and_exit; 1436 } 1437 if (!buffer_verified(bh) && 1438 !is_dx_internal_node(dir, block, 1439 (struct ext4_dir_entry *)bh->b_data) && 1440 !ext4_dirent_csum_verify(dir, 1441 (struct ext4_dir_entry *)bh->b_data)) { 1442 EXT4_ERROR_INODE(dir, "checksumming directory " 1443 "block %lu", (unsigned long)block); 1444 brelse(bh); 1445 ret = ERR_PTR(-EFSBADCRC); 1446 goto cleanup_and_exit; 1447 } 1448 set_buffer_verified(bh); 1449 i = search_dirblock(bh, dir, &fname, 1450 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); 1451 if (i == 1) { 1452 EXT4_I(dir)->i_dir_start_lookup = block; 1453 ret = bh; 1454 goto cleanup_and_exit; 1455 } else { 1456 brelse(bh); 1457 if (i < 0) 1458 goto cleanup_and_exit; 1459 } 1460 next: 1461 if (++block >= nblocks) 1462 block = 0; 1463 } while (block != start); 1464 1465 /* 1466 * If the directory has grown while we were searching, then 1467 * search the last part of the directory before giving up. 1468 */ 1469 block = nblocks; 1470 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1471 if (block < nblocks) { 1472 start = 0; 1473 goto restart; 1474 } 1475 1476 cleanup_and_exit: 1477 /* Clean up the read-ahead blocks */ 1478 for (; ra_ptr < ra_max; ra_ptr++) 1479 brelse(bh_use[ra_ptr]); 1480 ext4_fname_free_filename(&fname); 1481 return ret; 1482 } 1483 1484 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 1485 struct ext4_filename *fname, 1486 struct ext4_dir_entry_2 **res_dir) 1487 { 1488 struct super_block * sb = dir->i_sb; 1489 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1490 struct buffer_head *bh; 1491 ext4_lblk_t block; 1492 int retval; 1493 1494 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1495 *res_dir = NULL; 1496 #endif 1497 frame = dx_probe(fname, dir, NULL, frames); 1498 if (IS_ERR(frame)) 1499 return (struct buffer_head *) frame; 1500 do { 1501 block = dx_get_block(frame->at); 1502 bh = ext4_read_dirblock(dir, block, DIRENT); 1503 if (IS_ERR(bh)) 1504 goto errout; 1505 1506 retval = search_dirblock(bh, dir, fname, 1507 block << EXT4_BLOCK_SIZE_BITS(sb), 1508 res_dir); 1509 if (retval == 1) 1510 goto success; 1511 brelse(bh); 1512 if (retval == -1) { 1513 bh = ERR_PTR(ERR_BAD_DX_DIR); 1514 goto errout; 1515 } 1516 1517 /* Check to see if we should continue to search */ 1518 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame, 1519 frames, NULL); 1520 if (retval < 0) { 1521 ext4_warning_inode(dir, 1522 "error %d reading directory index block", 1523 retval); 1524 bh = ERR_PTR(retval); 1525 goto errout; 1526 } 1527 } while (retval == 1); 1528 1529 bh = NULL; 1530 errout: 1531 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name)); 1532 success: 1533 dx_release(frames); 1534 return bh; 1535 } 1536 1537 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 1538 { 1539 struct inode *inode; 1540 struct ext4_dir_entry_2 *de; 1541 struct buffer_head *bh; 1542 int err; 1543 1544 err = fscrypt_prepare_lookup(dir, dentry, flags); 1545 if (err) 1546 return ERR_PTR(err); 1547 1548 if (dentry->d_name.len > EXT4_NAME_LEN) 1549 return ERR_PTR(-ENAMETOOLONG); 1550 1551 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 1552 if (IS_ERR(bh)) 1553 return (struct dentry *) bh; 1554 inode = NULL; 1555 if (bh) { 1556 __u32 ino = le32_to_cpu(de->inode); 1557 brelse(bh); 1558 if (!ext4_valid_inum(dir->i_sb, ino)) { 1559 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); 1560 return ERR_PTR(-EFSCORRUPTED); 1561 } 1562 if (unlikely(ino == dir->i_ino)) { 1563 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir", 1564 dentry); 1565 return ERR_PTR(-EFSCORRUPTED); 1566 } 1567 inode = ext4_iget_normal(dir->i_sb, ino); 1568 if (inode == ERR_PTR(-ESTALE)) { 1569 EXT4_ERROR_INODE(dir, 1570 "deleted inode referenced: %u", 1571 ino); 1572 return ERR_PTR(-EFSCORRUPTED); 1573 } 1574 if (!IS_ERR(inode) && ext4_encrypted_inode(dir) && 1575 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && 1576 !fscrypt_has_permitted_context(dir, inode)) { 1577 ext4_warning(inode->i_sb, 1578 "Inconsistent encryption contexts: %lu/%lu", 1579 dir->i_ino, inode->i_ino); 1580 iput(inode); 1581 return ERR_PTR(-EPERM); 1582 } 1583 } 1584 return d_splice_alias(inode, dentry); 1585 } 1586 1587 1588 struct dentry *ext4_get_parent(struct dentry *child) 1589 { 1590 __u32 ino; 1591 static const struct qstr dotdot = QSTR_INIT("..", 2); 1592 struct ext4_dir_entry_2 * de; 1593 struct buffer_head *bh; 1594 1595 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL); 1596 if (IS_ERR(bh)) 1597 return (struct dentry *) bh; 1598 if (!bh) 1599 return ERR_PTR(-ENOENT); 1600 ino = le32_to_cpu(de->inode); 1601 brelse(bh); 1602 1603 if (!ext4_valid_inum(child->d_sb, ino)) { 1604 EXT4_ERROR_INODE(d_inode(child), 1605 "bad parent inode number: %u", ino); 1606 return ERR_PTR(-EFSCORRUPTED); 1607 } 1608 1609 return d_obtain_alias(ext4_iget_normal(child->d_sb, ino)); 1610 } 1611 1612 /* 1613 * Move count entries from end of map between two memory locations. 1614 * Returns pointer to last entry moved. 1615 */ 1616 static struct ext4_dir_entry_2 * 1617 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, 1618 unsigned blocksize) 1619 { 1620 unsigned rec_len = 0; 1621 1622 while (count--) { 1623 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) 1624 (from + (map->offs<<2)); 1625 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1626 memcpy (to, de, rec_len); 1627 ((struct ext4_dir_entry_2 *) to)->rec_len = 1628 ext4_rec_len_to_disk(rec_len, blocksize); 1629 de->inode = 0; 1630 map++; 1631 to += rec_len; 1632 } 1633 return (struct ext4_dir_entry_2 *) (to - rec_len); 1634 } 1635 1636 /* 1637 * Compact each dir entry in the range to the minimal rec_len. 1638 * Returns pointer to last entry in range. 1639 */ 1640 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) 1641 { 1642 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; 1643 unsigned rec_len = 0; 1644 1645 prev = to = de; 1646 while ((char*)de < base + blocksize) { 1647 next = ext4_next_entry(de, blocksize); 1648 if (de->inode && de->name_len) { 1649 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1650 if (de > to) 1651 memmove(to, de, rec_len); 1652 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); 1653 prev = to; 1654 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); 1655 } 1656 de = next; 1657 } 1658 return prev; 1659 } 1660 1661 /* 1662 * Split a full leaf block to make room for a new dir entry. 1663 * Allocate a new block, and move entries so that they are approx. equally full. 1664 * Returns pointer to de in block into which the new entry will be inserted. 1665 */ 1666 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1667 struct buffer_head **bh,struct dx_frame *frame, 1668 struct dx_hash_info *hinfo) 1669 { 1670 unsigned blocksize = dir->i_sb->s_blocksize; 1671 unsigned count, continued; 1672 struct buffer_head *bh2; 1673 ext4_lblk_t newblock; 1674 u32 hash2; 1675 struct dx_map_entry *map; 1676 char *data1 = (*bh)->b_data, *data2; 1677 unsigned split, move, size; 1678 struct ext4_dir_entry_2 *de = NULL, *de2; 1679 struct ext4_dir_entry_tail *t; 1680 int csum_size = 0; 1681 int err = 0, i; 1682 1683 if (ext4_has_metadata_csum(dir->i_sb)) 1684 csum_size = sizeof(struct ext4_dir_entry_tail); 1685 1686 bh2 = ext4_append(handle, dir, &newblock); 1687 if (IS_ERR(bh2)) { 1688 brelse(*bh); 1689 *bh = NULL; 1690 return (struct ext4_dir_entry_2 *) bh2; 1691 } 1692 1693 BUFFER_TRACE(*bh, "get_write_access"); 1694 err = ext4_journal_get_write_access(handle, *bh); 1695 if (err) 1696 goto journal_error; 1697 1698 BUFFER_TRACE(frame->bh, "get_write_access"); 1699 err = ext4_journal_get_write_access(handle, frame->bh); 1700 if (err) 1701 goto journal_error; 1702 1703 data2 = bh2->b_data; 1704 1705 /* create map in the end of data2 block */ 1706 map = (struct dx_map_entry *) (data2 + blocksize); 1707 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1, 1708 blocksize, hinfo, map); 1709 map -= count; 1710 dx_sort_map(map, count); 1711 /* Split the existing block in the middle, size-wise */ 1712 size = 0; 1713 move = 0; 1714 for (i = count-1; i >= 0; i--) { 1715 /* is more than half of this entry in 2nd half of the block? */ 1716 if (size + map[i].size/2 > blocksize/2) 1717 break; 1718 size += map[i].size; 1719 move++; 1720 } 1721 /* map index at which we will split */ 1722 split = count - move; 1723 hash2 = map[split].hash; 1724 continued = hash2 == map[split - 1].hash; 1725 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", 1726 (unsigned long)dx_get_block(frame->at), 1727 hash2, split, count-split)); 1728 1729 /* Fancy dance to stay within two buffers */ 1730 de2 = dx_move_dirents(data1, data2, map + split, count - split, 1731 blocksize); 1732 de = dx_pack_dirents(data1, blocksize); 1733 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1734 (char *) de, 1735 blocksize); 1736 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - 1737 (char *) de2, 1738 blocksize); 1739 if (csum_size) { 1740 t = EXT4_DIRENT_TAIL(data2, blocksize); 1741 initialize_dirent_tail(t, blocksize); 1742 1743 t = EXT4_DIRENT_TAIL(data1, blocksize); 1744 initialize_dirent_tail(t, blocksize); 1745 } 1746 1747 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1, 1748 blocksize, 1)); 1749 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2, 1750 blocksize, 1)); 1751 1752 /* Which block gets the new entry? */ 1753 if (hinfo->hash >= hash2) { 1754 swap(*bh, bh2); 1755 de = de2; 1756 } 1757 dx_insert_block(frame, hash2 + continued, newblock); 1758 err = ext4_handle_dirty_dirent_node(handle, dir, bh2); 1759 if (err) 1760 goto journal_error; 1761 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1762 if (err) 1763 goto journal_error; 1764 brelse(bh2); 1765 dxtrace(dx_show_index("frame", frame->entries)); 1766 return de; 1767 1768 journal_error: 1769 brelse(*bh); 1770 brelse(bh2); 1771 *bh = NULL; 1772 ext4_std_error(dir->i_sb, err); 1773 return ERR_PTR(err); 1774 } 1775 1776 int ext4_find_dest_de(struct inode *dir, struct inode *inode, 1777 struct buffer_head *bh, 1778 void *buf, int buf_size, 1779 struct ext4_filename *fname, 1780 struct ext4_dir_entry_2 **dest_de) 1781 { 1782 struct ext4_dir_entry_2 *de; 1783 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname)); 1784 int nlen, rlen; 1785 unsigned int offset = 0; 1786 char *top; 1787 1788 de = (struct ext4_dir_entry_2 *)buf; 1789 top = buf + buf_size - reclen; 1790 while ((char *) de <= top) { 1791 if (ext4_check_dir_entry(dir, NULL, de, bh, 1792 buf, buf_size, offset)) 1793 return -EFSCORRUPTED; 1794 if (ext4_match(fname, de)) 1795 return -EEXIST; 1796 nlen = EXT4_DIR_REC_LEN(de->name_len); 1797 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1798 if ((de->inode ? rlen - nlen : rlen) >= reclen) 1799 break; 1800 de = (struct ext4_dir_entry_2 *)((char *)de + rlen); 1801 offset += rlen; 1802 } 1803 if ((char *) de > top) 1804 return -ENOSPC; 1805 1806 *dest_de = de; 1807 return 0; 1808 } 1809 1810 void ext4_insert_dentry(struct inode *inode, 1811 struct ext4_dir_entry_2 *de, 1812 int buf_size, 1813 struct ext4_filename *fname) 1814 { 1815 1816 int nlen, rlen; 1817 1818 nlen = EXT4_DIR_REC_LEN(de->name_len); 1819 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1820 if (de->inode) { 1821 struct ext4_dir_entry_2 *de1 = 1822 (struct ext4_dir_entry_2 *)((char *)de + nlen); 1823 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); 1824 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); 1825 de = de1; 1826 } 1827 de->file_type = EXT4_FT_UNKNOWN; 1828 de->inode = cpu_to_le32(inode->i_ino); 1829 ext4_set_de_type(inode->i_sb, de, inode->i_mode); 1830 de->name_len = fname_len(fname); 1831 memcpy(de->name, fname_name(fname), fname_len(fname)); 1832 } 1833 1834 /* 1835 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1836 * it points to a directory entry which is guaranteed to be large 1837 * enough for new directory entry. If de is NULL, then 1838 * add_dirent_to_buf will attempt search the directory block for 1839 * space. It will return -ENOSPC if no space is available, and -EIO 1840 * and -EEXIST if directory entry already exists. 1841 */ 1842 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname, 1843 struct inode *dir, 1844 struct inode *inode, struct ext4_dir_entry_2 *de, 1845 struct buffer_head *bh) 1846 { 1847 unsigned int blocksize = dir->i_sb->s_blocksize; 1848 int csum_size = 0; 1849 int err; 1850 1851 if (ext4_has_metadata_csum(inode->i_sb)) 1852 csum_size = sizeof(struct ext4_dir_entry_tail); 1853 1854 if (!de) { 1855 err = ext4_find_dest_de(dir, inode, bh, bh->b_data, 1856 blocksize - csum_size, fname, &de); 1857 if (err) 1858 return err; 1859 } 1860 BUFFER_TRACE(bh, "get_write_access"); 1861 err = ext4_journal_get_write_access(handle, bh); 1862 if (err) { 1863 ext4_std_error(dir->i_sb, err); 1864 return err; 1865 } 1866 1867 /* By now the buffer is marked for journaling */ 1868 ext4_insert_dentry(inode, de, blocksize, fname); 1869 1870 /* 1871 * XXX shouldn't update any times until successful 1872 * completion of syscall, but too many callers depend 1873 * on this. 1874 * 1875 * XXX similarly, too many callers depend on 1876 * ext4_new_inode() setting the times, but error 1877 * recovery deletes the inode, so the worst that can 1878 * happen is that the times are slightly out of date 1879 * and/or different from the directory change time. 1880 */ 1881 dir->i_mtime = dir->i_ctime = current_time(dir); 1882 ext4_update_dx_flag(dir); 1883 inode_inc_iversion(dir); 1884 ext4_mark_inode_dirty(handle, dir); 1885 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 1886 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 1887 if (err) 1888 ext4_std_error(dir->i_sb, err); 1889 return 0; 1890 } 1891 1892 /* 1893 * This converts a one block unindexed directory to a 3 block indexed 1894 * directory, and adds the dentry to the indexed directory. 1895 */ 1896 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, 1897 struct inode *dir, 1898 struct inode *inode, struct buffer_head *bh) 1899 { 1900 struct buffer_head *bh2; 1901 struct dx_root *root; 1902 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1903 struct dx_entry *entries; 1904 struct ext4_dir_entry_2 *de, *de2; 1905 struct ext4_dir_entry_tail *t; 1906 char *data1, *top; 1907 unsigned len; 1908 int retval; 1909 unsigned blocksize; 1910 ext4_lblk_t block; 1911 struct fake_dirent *fde; 1912 int csum_size = 0; 1913 1914 if (ext4_has_metadata_csum(inode->i_sb)) 1915 csum_size = sizeof(struct ext4_dir_entry_tail); 1916 1917 blocksize = dir->i_sb->s_blocksize; 1918 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); 1919 BUFFER_TRACE(bh, "get_write_access"); 1920 retval = ext4_journal_get_write_access(handle, bh); 1921 if (retval) { 1922 ext4_std_error(dir->i_sb, retval); 1923 brelse(bh); 1924 return retval; 1925 } 1926 root = (struct dx_root *) bh->b_data; 1927 1928 /* The 0th block becomes the root, move the dirents out */ 1929 fde = &root->dotdot; 1930 de = (struct ext4_dir_entry_2 *)((char *)fde + 1931 ext4_rec_len_from_disk(fde->rec_len, blocksize)); 1932 if ((char *) de >= (((char *) root) + blocksize)) { 1933 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); 1934 brelse(bh); 1935 return -EFSCORRUPTED; 1936 } 1937 len = ((char *) root) + (blocksize - csum_size) - (char *) de; 1938 1939 /* Allocate new block for the 0th block's dirents */ 1940 bh2 = ext4_append(handle, dir, &block); 1941 if (IS_ERR(bh2)) { 1942 brelse(bh); 1943 return PTR_ERR(bh2); 1944 } 1945 ext4_set_inode_flag(dir, EXT4_INODE_INDEX); 1946 data1 = bh2->b_data; 1947 1948 memcpy (data1, de, len); 1949 de = (struct ext4_dir_entry_2 *) data1; 1950 top = data1 + len; 1951 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) 1952 de = de2; 1953 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1954 (char *) de, 1955 blocksize); 1956 1957 if (csum_size) { 1958 t = EXT4_DIRENT_TAIL(data1, blocksize); 1959 initialize_dirent_tail(t, blocksize); 1960 } 1961 1962 /* Initialize the root; the dot dirents already exist */ 1963 de = (struct ext4_dir_entry_2 *) (&root->dotdot); 1964 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), 1965 blocksize); 1966 memset (&root->info, 0, sizeof(root->info)); 1967 root->info.info_length = sizeof(root->info); 1968 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1969 entries = root->entries; 1970 dx_set_block(entries, 1); 1971 dx_set_count(entries, 1); 1972 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); 1973 1974 /* Initialize as for dx_probe */ 1975 fname->hinfo.hash_version = root->info.hash_version; 1976 if (fname->hinfo.hash_version <= DX_HASH_TEA) 1977 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 1978 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1979 ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo); 1980 1981 memset(frames, 0, sizeof(frames)); 1982 frame = frames; 1983 frame->entries = entries; 1984 frame->at = entries; 1985 frame->bh = bh; 1986 1987 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1988 if (retval) 1989 goto out_frames; 1990 retval = ext4_handle_dirty_dirent_node(handle, dir, bh2); 1991 if (retval) 1992 goto out_frames; 1993 1994 de = do_split(handle,dir, &bh2, frame, &fname->hinfo); 1995 if (IS_ERR(de)) { 1996 retval = PTR_ERR(de); 1997 goto out_frames; 1998 } 1999 2000 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2); 2001 out_frames: 2002 /* 2003 * Even if the block split failed, we have to properly write 2004 * out all the changes we did so far. Otherwise we can end up 2005 * with corrupted filesystem. 2006 */ 2007 if (retval) 2008 ext4_mark_inode_dirty(handle, dir); 2009 dx_release(frames); 2010 brelse(bh2); 2011 return retval; 2012 } 2013 2014 /* 2015 * ext4_add_entry() 2016 * 2017 * adds a file entry to the specified directory, using the same 2018 * semantics as ext4_find_entry(). It returns NULL if it failed. 2019 * 2020 * NOTE!! The inode part of 'de' is left at 0 - which means you 2021 * may not sleep between calling this and putting something into 2022 * the entry, as someone else might have used it while you slept. 2023 */ 2024 static int ext4_add_entry(handle_t *handle, struct dentry *dentry, 2025 struct inode *inode) 2026 { 2027 struct inode *dir = d_inode(dentry->d_parent); 2028 struct buffer_head *bh = NULL; 2029 struct ext4_dir_entry_2 *de; 2030 struct ext4_dir_entry_tail *t; 2031 struct super_block *sb; 2032 struct ext4_filename fname; 2033 int retval; 2034 int dx_fallback=0; 2035 unsigned blocksize; 2036 ext4_lblk_t block, blocks; 2037 int csum_size = 0; 2038 2039 if (ext4_has_metadata_csum(inode->i_sb)) 2040 csum_size = sizeof(struct ext4_dir_entry_tail); 2041 2042 sb = dir->i_sb; 2043 blocksize = sb->s_blocksize; 2044 if (!dentry->d_name.len) 2045 return -EINVAL; 2046 2047 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname); 2048 if (retval) 2049 return retval; 2050 2051 if (ext4_has_inline_data(dir)) { 2052 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode); 2053 if (retval < 0) 2054 goto out; 2055 if (retval == 1) { 2056 retval = 0; 2057 goto out; 2058 } 2059 } 2060 2061 if (is_dx(dir)) { 2062 retval = ext4_dx_add_entry(handle, &fname, dir, inode); 2063 if (!retval || (retval != ERR_BAD_DX_DIR)) 2064 goto out; 2065 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); 2066 dx_fallback++; 2067 ext4_mark_inode_dirty(handle, dir); 2068 } 2069 blocks = dir->i_size >> sb->s_blocksize_bits; 2070 for (block = 0; block < blocks; block++) { 2071 bh = ext4_read_dirblock(dir, block, DIRENT); 2072 if (IS_ERR(bh)) { 2073 retval = PTR_ERR(bh); 2074 bh = NULL; 2075 goto out; 2076 } 2077 retval = add_dirent_to_buf(handle, &fname, dir, inode, 2078 NULL, bh); 2079 if (retval != -ENOSPC) 2080 goto out; 2081 2082 if (blocks == 1 && !dx_fallback && 2083 ext4_has_feature_dir_index(sb)) { 2084 retval = make_indexed_dir(handle, &fname, dir, 2085 inode, bh); 2086 bh = NULL; /* make_indexed_dir releases bh */ 2087 goto out; 2088 } 2089 brelse(bh); 2090 } 2091 bh = ext4_append(handle, dir, &block); 2092 if (IS_ERR(bh)) { 2093 retval = PTR_ERR(bh); 2094 bh = NULL; 2095 goto out; 2096 } 2097 de = (struct ext4_dir_entry_2 *) bh->b_data; 2098 de->inode = 0; 2099 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize); 2100 2101 if (csum_size) { 2102 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize); 2103 initialize_dirent_tail(t, blocksize); 2104 } 2105 2106 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh); 2107 out: 2108 ext4_fname_free_filename(&fname); 2109 brelse(bh); 2110 if (retval == 0) 2111 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); 2112 return retval; 2113 } 2114 2115 /* 2116 * Returns 0 for success, or a negative error value 2117 */ 2118 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 2119 struct inode *dir, struct inode *inode) 2120 { 2121 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 2122 struct dx_entry *entries, *at; 2123 struct buffer_head *bh; 2124 struct super_block *sb = dir->i_sb; 2125 struct ext4_dir_entry_2 *de; 2126 int restart; 2127 int err; 2128 2129 again: 2130 restart = 0; 2131 frame = dx_probe(fname, dir, NULL, frames); 2132 if (IS_ERR(frame)) 2133 return PTR_ERR(frame); 2134 entries = frame->entries; 2135 at = frame->at; 2136 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT); 2137 if (IS_ERR(bh)) { 2138 err = PTR_ERR(bh); 2139 bh = NULL; 2140 goto cleanup; 2141 } 2142 2143 BUFFER_TRACE(bh, "get_write_access"); 2144 err = ext4_journal_get_write_access(handle, bh); 2145 if (err) 2146 goto journal_error; 2147 2148 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh); 2149 if (err != -ENOSPC) 2150 goto cleanup; 2151 2152 err = 0; 2153 /* Block full, should compress but for now just split */ 2154 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n", 2155 dx_get_count(entries), dx_get_limit(entries))); 2156 /* Need to split index? */ 2157 if (dx_get_count(entries) == dx_get_limit(entries)) { 2158 ext4_lblk_t newblock; 2159 int levels = frame - frames + 1; 2160 unsigned int icount; 2161 int add_level = 1; 2162 struct dx_entry *entries2; 2163 struct dx_node *node2; 2164 struct buffer_head *bh2; 2165 2166 while (frame > frames) { 2167 if (dx_get_count((frame - 1)->entries) < 2168 dx_get_limit((frame - 1)->entries)) { 2169 add_level = 0; 2170 break; 2171 } 2172 frame--; /* split higher index block */ 2173 at = frame->at; 2174 entries = frame->entries; 2175 restart = 1; 2176 } 2177 if (add_level && levels == ext4_dir_htree_level(sb)) { 2178 ext4_warning(sb, "Directory (ino: %lu) index full, " 2179 "reach max htree level :%d", 2180 dir->i_ino, levels); 2181 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) { 2182 ext4_warning(sb, "Large directory feature is " 2183 "not enabled on this " 2184 "filesystem"); 2185 } 2186 err = -ENOSPC; 2187 goto cleanup; 2188 } 2189 icount = dx_get_count(entries); 2190 bh2 = ext4_append(handle, dir, &newblock); 2191 if (IS_ERR(bh2)) { 2192 err = PTR_ERR(bh2); 2193 goto cleanup; 2194 } 2195 node2 = (struct dx_node *)(bh2->b_data); 2196 entries2 = node2->entries; 2197 memset(&node2->fake, 0, sizeof(struct fake_dirent)); 2198 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, 2199 sb->s_blocksize); 2200 BUFFER_TRACE(frame->bh, "get_write_access"); 2201 err = ext4_journal_get_write_access(handle, frame->bh); 2202 if (err) 2203 goto journal_error; 2204 if (!add_level) { 2205 unsigned icount1 = icount/2, icount2 = icount - icount1; 2206 unsigned hash2 = dx_get_hash(entries + icount1); 2207 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n", 2208 icount1, icount2)); 2209 2210 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 2211 err = ext4_journal_get_write_access(handle, 2212 (frame - 1)->bh); 2213 if (err) 2214 goto journal_error; 2215 2216 memcpy((char *) entries2, (char *) (entries + icount1), 2217 icount2 * sizeof(struct dx_entry)); 2218 dx_set_count(entries, icount1); 2219 dx_set_count(entries2, icount2); 2220 dx_set_limit(entries2, dx_node_limit(dir)); 2221 2222 /* Which index block gets the new entry? */ 2223 if (at - entries >= icount1) { 2224 frame->at = at = at - entries - icount1 + entries2; 2225 frame->entries = entries = entries2; 2226 swap(frame->bh, bh2); 2227 } 2228 dx_insert_block((frame - 1), hash2, newblock); 2229 dxtrace(dx_show_index("node", frame->entries)); 2230 dxtrace(dx_show_index("node", 2231 ((struct dx_node *) bh2->b_data)->entries)); 2232 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2233 if (err) 2234 goto journal_error; 2235 brelse (bh2); 2236 err = ext4_handle_dirty_dx_node(handle, dir, 2237 (frame - 1)->bh); 2238 if (err) 2239 goto journal_error; 2240 if (restart) { 2241 err = ext4_handle_dirty_dx_node(handle, dir, 2242 frame->bh); 2243 goto journal_error; 2244 } 2245 } else { 2246 struct dx_root *dxroot; 2247 memcpy((char *) entries2, (char *) entries, 2248 icount * sizeof(struct dx_entry)); 2249 dx_set_limit(entries2, dx_node_limit(dir)); 2250 2251 /* Set up root */ 2252 dx_set_count(entries, 1); 2253 dx_set_block(entries + 0, newblock); 2254 dxroot = (struct dx_root *)frames[0].bh->b_data; 2255 dxroot->info.indirect_levels += 1; 2256 dxtrace(printk(KERN_DEBUG 2257 "Creating %d level index...\n", 2258 info->indirect_levels)); 2259 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2260 if (err) 2261 goto journal_error; 2262 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2263 brelse(bh2); 2264 restart = 1; 2265 goto journal_error; 2266 } 2267 } 2268 de = do_split(handle, dir, &bh, frame, &fname->hinfo); 2269 if (IS_ERR(de)) { 2270 err = PTR_ERR(de); 2271 goto cleanup; 2272 } 2273 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh); 2274 goto cleanup; 2275 2276 journal_error: 2277 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */ 2278 cleanup: 2279 brelse(bh); 2280 dx_release(frames); 2281 /* @restart is true means htree-path has been changed, we need to 2282 * repeat dx_probe() to find out valid htree-path 2283 */ 2284 if (restart && err == 0) 2285 goto again; 2286 return err; 2287 } 2288 2289 /* 2290 * ext4_generic_delete_entry deletes a directory entry by merging it 2291 * with the previous entry 2292 */ 2293 int ext4_generic_delete_entry(handle_t *handle, 2294 struct inode *dir, 2295 struct ext4_dir_entry_2 *de_del, 2296 struct buffer_head *bh, 2297 void *entry_buf, 2298 int buf_size, 2299 int csum_size) 2300 { 2301 struct ext4_dir_entry_2 *de, *pde; 2302 unsigned int blocksize = dir->i_sb->s_blocksize; 2303 int i; 2304 2305 i = 0; 2306 pde = NULL; 2307 de = (struct ext4_dir_entry_2 *)entry_buf; 2308 while (i < buf_size - csum_size) { 2309 if (ext4_check_dir_entry(dir, NULL, de, bh, 2310 bh->b_data, bh->b_size, i)) 2311 return -EFSCORRUPTED; 2312 if (de == de_del) { 2313 if (pde) 2314 pde->rec_len = ext4_rec_len_to_disk( 2315 ext4_rec_len_from_disk(pde->rec_len, 2316 blocksize) + 2317 ext4_rec_len_from_disk(de->rec_len, 2318 blocksize), 2319 blocksize); 2320 else 2321 de->inode = 0; 2322 inode_inc_iversion(dir); 2323 return 0; 2324 } 2325 i += ext4_rec_len_from_disk(de->rec_len, blocksize); 2326 pde = de; 2327 de = ext4_next_entry(de, blocksize); 2328 } 2329 return -ENOENT; 2330 } 2331 2332 static int ext4_delete_entry(handle_t *handle, 2333 struct inode *dir, 2334 struct ext4_dir_entry_2 *de_del, 2335 struct buffer_head *bh) 2336 { 2337 int err, csum_size = 0; 2338 2339 if (ext4_has_inline_data(dir)) { 2340 int has_inline_data = 1; 2341 err = ext4_delete_inline_entry(handle, dir, de_del, bh, 2342 &has_inline_data); 2343 if (has_inline_data) 2344 return err; 2345 } 2346 2347 if (ext4_has_metadata_csum(dir->i_sb)) 2348 csum_size = sizeof(struct ext4_dir_entry_tail); 2349 2350 BUFFER_TRACE(bh, "get_write_access"); 2351 err = ext4_journal_get_write_access(handle, bh); 2352 if (unlikely(err)) 2353 goto out; 2354 2355 err = ext4_generic_delete_entry(handle, dir, de_del, 2356 bh, bh->b_data, 2357 dir->i_sb->s_blocksize, csum_size); 2358 if (err) 2359 goto out; 2360 2361 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 2362 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 2363 if (unlikely(err)) 2364 goto out; 2365 2366 return 0; 2367 out: 2368 if (err != -ENOENT) 2369 ext4_std_error(dir->i_sb, err); 2370 return err; 2371 } 2372 2373 /* 2374 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2 2375 * since this indicates that nlinks count was previously 1 to avoid overflowing 2376 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean 2377 * that subdirectory link counts are not being maintained accurately. 2378 * 2379 * The caller has already checked for i_nlink overflow in case the DIR_LINK 2380 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy 2381 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set 2382 * on regular files) and to avoid creating huge/slow non-HTREE directories. 2383 */ 2384 static void ext4_inc_count(handle_t *handle, struct inode *inode) 2385 { 2386 inc_nlink(inode); 2387 if (is_dx(inode) && 2388 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2)) 2389 set_nlink(inode, 1); 2390 } 2391 2392 /* 2393 * If a directory had nlink == 1, then we should let it be 1. This indicates 2394 * directory has >EXT4_LINK_MAX subdirs. 2395 */ 2396 static void ext4_dec_count(handle_t *handle, struct inode *inode) 2397 { 2398 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) 2399 drop_nlink(inode); 2400 } 2401 2402 2403 static int ext4_add_nondir(handle_t *handle, 2404 struct dentry *dentry, struct inode *inode) 2405 { 2406 int err = ext4_add_entry(handle, dentry, inode); 2407 if (!err) { 2408 ext4_mark_inode_dirty(handle, inode); 2409 unlock_new_inode(inode); 2410 d_instantiate(dentry, inode); 2411 return 0; 2412 } 2413 drop_nlink(inode); 2414 unlock_new_inode(inode); 2415 iput(inode); 2416 return err; 2417 } 2418 2419 /* 2420 * By the time this is called, we already have created 2421 * the directory cache entry for the new file, but it 2422 * is so far negative - it has no inode. 2423 * 2424 * If the create succeeds, we fill in the inode information 2425 * with d_instantiate(). 2426 */ 2427 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, 2428 bool excl) 2429 { 2430 handle_t *handle; 2431 struct inode *inode; 2432 int err, credits, retries = 0; 2433 2434 err = dquot_initialize(dir); 2435 if (err) 2436 return err; 2437 2438 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2439 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2440 retry: 2441 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2442 NULL, EXT4_HT_DIR, credits); 2443 handle = ext4_journal_current_handle(); 2444 err = PTR_ERR(inode); 2445 if (!IS_ERR(inode)) { 2446 inode->i_op = &ext4_file_inode_operations; 2447 inode->i_fop = &ext4_file_operations; 2448 ext4_set_aops(inode); 2449 err = ext4_add_nondir(handle, dentry, inode); 2450 if (!err && IS_DIRSYNC(dir)) 2451 ext4_handle_sync(handle); 2452 } 2453 if (handle) 2454 ext4_journal_stop(handle); 2455 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2456 goto retry; 2457 return err; 2458 } 2459 2460 static int ext4_mknod(struct inode *dir, struct dentry *dentry, 2461 umode_t mode, dev_t rdev) 2462 { 2463 handle_t *handle; 2464 struct inode *inode; 2465 int err, credits, retries = 0; 2466 2467 err = dquot_initialize(dir); 2468 if (err) 2469 return err; 2470 2471 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2472 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2473 retry: 2474 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2475 NULL, EXT4_HT_DIR, credits); 2476 handle = ext4_journal_current_handle(); 2477 err = PTR_ERR(inode); 2478 if (!IS_ERR(inode)) { 2479 init_special_inode(inode, inode->i_mode, rdev); 2480 inode->i_op = &ext4_special_inode_operations; 2481 err = ext4_add_nondir(handle, dentry, inode); 2482 if (!err && IS_DIRSYNC(dir)) 2483 ext4_handle_sync(handle); 2484 } 2485 if (handle) 2486 ext4_journal_stop(handle); 2487 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2488 goto retry; 2489 return err; 2490 } 2491 2492 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 2493 { 2494 handle_t *handle; 2495 struct inode *inode; 2496 int err, retries = 0; 2497 2498 err = dquot_initialize(dir); 2499 if (err) 2500 return err; 2501 2502 retry: 2503 inode = ext4_new_inode_start_handle(dir, mode, 2504 NULL, 0, NULL, 2505 EXT4_HT_DIR, 2506 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 2507 4 + EXT4_XATTR_TRANS_BLOCKS); 2508 handle = ext4_journal_current_handle(); 2509 err = PTR_ERR(inode); 2510 if (!IS_ERR(inode)) { 2511 inode->i_op = &ext4_file_inode_operations; 2512 inode->i_fop = &ext4_file_operations; 2513 ext4_set_aops(inode); 2514 d_tmpfile(dentry, inode); 2515 err = ext4_orphan_add(handle, inode); 2516 if (err) 2517 goto err_unlock_inode; 2518 mark_inode_dirty(inode); 2519 unlock_new_inode(inode); 2520 } 2521 if (handle) 2522 ext4_journal_stop(handle); 2523 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2524 goto retry; 2525 return err; 2526 err_unlock_inode: 2527 ext4_journal_stop(handle); 2528 unlock_new_inode(inode); 2529 return err; 2530 } 2531 2532 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode, 2533 struct ext4_dir_entry_2 *de, 2534 int blocksize, int csum_size, 2535 unsigned int parent_ino, int dotdot_real_len) 2536 { 2537 de->inode = cpu_to_le32(inode->i_ino); 2538 de->name_len = 1; 2539 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), 2540 blocksize); 2541 strcpy(de->name, "."); 2542 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2543 2544 de = ext4_next_entry(de, blocksize); 2545 de->inode = cpu_to_le32(parent_ino); 2546 de->name_len = 2; 2547 if (!dotdot_real_len) 2548 de->rec_len = ext4_rec_len_to_disk(blocksize - 2549 (csum_size + EXT4_DIR_REC_LEN(1)), 2550 blocksize); 2551 else 2552 de->rec_len = ext4_rec_len_to_disk( 2553 EXT4_DIR_REC_LEN(de->name_len), blocksize); 2554 strcpy(de->name, ".."); 2555 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2556 2557 return ext4_next_entry(de, blocksize); 2558 } 2559 2560 static int ext4_init_new_dir(handle_t *handle, struct inode *dir, 2561 struct inode *inode) 2562 { 2563 struct buffer_head *dir_block = NULL; 2564 struct ext4_dir_entry_2 *de; 2565 struct ext4_dir_entry_tail *t; 2566 ext4_lblk_t block = 0; 2567 unsigned int blocksize = dir->i_sb->s_blocksize; 2568 int csum_size = 0; 2569 int err; 2570 2571 if (ext4_has_metadata_csum(dir->i_sb)) 2572 csum_size = sizeof(struct ext4_dir_entry_tail); 2573 2574 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { 2575 err = ext4_try_create_inline_dir(handle, dir, inode); 2576 if (err < 0 && err != -ENOSPC) 2577 goto out; 2578 if (!err) 2579 goto out; 2580 } 2581 2582 inode->i_size = 0; 2583 dir_block = ext4_append(handle, inode, &block); 2584 if (IS_ERR(dir_block)) 2585 return PTR_ERR(dir_block); 2586 de = (struct ext4_dir_entry_2 *)dir_block->b_data; 2587 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0); 2588 set_nlink(inode, 2); 2589 if (csum_size) { 2590 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize); 2591 initialize_dirent_tail(t, blocksize); 2592 } 2593 2594 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); 2595 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block); 2596 if (err) 2597 goto out; 2598 set_buffer_verified(dir_block); 2599 out: 2600 brelse(dir_block); 2601 return err; 2602 } 2603 2604 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2605 { 2606 handle_t *handle; 2607 struct inode *inode; 2608 int err, credits, retries = 0; 2609 2610 if (EXT4_DIR_LINK_MAX(dir)) 2611 return -EMLINK; 2612 2613 err = dquot_initialize(dir); 2614 if (err) 2615 return err; 2616 2617 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2618 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2619 retry: 2620 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode, 2621 &dentry->d_name, 2622 0, NULL, EXT4_HT_DIR, credits); 2623 handle = ext4_journal_current_handle(); 2624 err = PTR_ERR(inode); 2625 if (IS_ERR(inode)) 2626 goto out_stop; 2627 2628 inode->i_op = &ext4_dir_inode_operations; 2629 inode->i_fop = &ext4_dir_operations; 2630 err = ext4_init_new_dir(handle, dir, inode); 2631 if (err) 2632 goto out_clear_inode; 2633 err = ext4_mark_inode_dirty(handle, inode); 2634 if (!err) 2635 err = ext4_add_entry(handle, dentry, inode); 2636 if (err) { 2637 out_clear_inode: 2638 clear_nlink(inode); 2639 unlock_new_inode(inode); 2640 ext4_mark_inode_dirty(handle, inode); 2641 iput(inode); 2642 goto out_stop; 2643 } 2644 ext4_inc_count(handle, dir); 2645 ext4_update_dx_flag(dir); 2646 err = ext4_mark_inode_dirty(handle, dir); 2647 if (err) 2648 goto out_clear_inode; 2649 unlock_new_inode(inode); 2650 d_instantiate(dentry, inode); 2651 if (IS_DIRSYNC(dir)) 2652 ext4_handle_sync(handle); 2653 2654 out_stop: 2655 if (handle) 2656 ext4_journal_stop(handle); 2657 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2658 goto retry; 2659 return err; 2660 } 2661 2662 /* 2663 * routine to check that the specified directory is empty (for rmdir) 2664 */ 2665 bool ext4_empty_dir(struct inode *inode) 2666 { 2667 unsigned int offset; 2668 struct buffer_head *bh; 2669 struct ext4_dir_entry_2 *de, *de1; 2670 struct super_block *sb; 2671 2672 if (ext4_has_inline_data(inode)) { 2673 int has_inline_data = 1; 2674 int ret; 2675 2676 ret = empty_inline_dir(inode, &has_inline_data); 2677 if (has_inline_data) 2678 return ret; 2679 } 2680 2681 sb = inode->i_sb; 2682 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { 2683 EXT4_ERROR_INODE(inode, "invalid size"); 2684 return true; 2685 } 2686 bh = ext4_read_dirblock(inode, 0, EITHER); 2687 if (IS_ERR(bh)) 2688 return true; 2689 2690 de = (struct ext4_dir_entry_2 *) bh->b_data; 2691 de1 = ext4_next_entry(de, sb->s_blocksize); 2692 if (le32_to_cpu(de->inode) != inode->i_ino || 2693 le32_to_cpu(de1->inode) == 0 || 2694 strcmp(".", de->name) || strcmp("..", de1->name)) { 2695 ext4_warning_inode(inode, "directory missing '.' and/or '..'"); 2696 brelse(bh); 2697 return true; 2698 } 2699 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + 2700 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); 2701 de = ext4_next_entry(de1, sb->s_blocksize); 2702 while (offset < inode->i_size) { 2703 if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 2704 unsigned int lblock; 2705 brelse(bh); 2706 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); 2707 bh = ext4_read_dirblock(inode, lblock, EITHER); 2708 if (IS_ERR(bh)) 2709 return true; 2710 de = (struct ext4_dir_entry_2 *) bh->b_data; 2711 } 2712 if (ext4_check_dir_entry(inode, NULL, de, bh, 2713 bh->b_data, bh->b_size, offset)) { 2714 de = (struct ext4_dir_entry_2 *)(bh->b_data + 2715 sb->s_blocksize); 2716 offset = (offset | (sb->s_blocksize - 1)) + 1; 2717 continue; 2718 } 2719 if (le32_to_cpu(de->inode)) { 2720 brelse(bh); 2721 return false; 2722 } 2723 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2724 de = ext4_next_entry(de, sb->s_blocksize); 2725 } 2726 brelse(bh); 2727 return true; 2728 } 2729 2730 /* 2731 * ext4_orphan_add() links an unlinked or truncated inode into a list of 2732 * such inodes, starting at the superblock, in case we crash before the 2733 * file is closed/deleted, or in case the inode truncate spans multiple 2734 * transactions and the last transaction is not recovered after a crash. 2735 * 2736 * At filesystem recovery time, we walk this list deleting unlinked 2737 * inodes and truncating linked inodes in ext4_orphan_cleanup(). 2738 * 2739 * Orphan list manipulation functions must be called under i_mutex unless 2740 * we are just creating the inode or deleting it. 2741 */ 2742 int ext4_orphan_add(handle_t *handle, struct inode *inode) 2743 { 2744 struct super_block *sb = inode->i_sb; 2745 struct ext4_sb_info *sbi = EXT4_SB(sb); 2746 struct ext4_iloc iloc; 2747 int err = 0, rc; 2748 bool dirty = false; 2749 2750 if (!sbi->s_journal || is_bad_inode(inode)) 2751 return 0; 2752 2753 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2754 !inode_is_locked(inode)); 2755 /* 2756 * Exit early if inode already is on orphan list. This is a big speedup 2757 * since we don't have to contend on the global s_orphan_lock. 2758 */ 2759 if (!list_empty(&EXT4_I(inode)->i_orphan)) 2760 return 0; 2761 2762 /* 2763 * Orphan handling is only valid for files with data blocks 2764 * being truncated, or files being unlinked. Note that we either 2765 * hold i_mutex, or the inode can not be referenced from outside, 2766 * so i_nlink should not be bumped due to race 2767 */ 2768 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2769 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 2770 2771 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2772 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2773 if (err) 2774 goto out; 2775 2776 err = ext4_reserve_inode_write(handle, inode, &iloc); 2777 if (err) 2778 goto out; 2779 2780 mutex_lock(&sbi->s_orphan_lock); 2781 /* 2782 * Due to previous errors inode may be already a part of on-disk 2783 * orphan list. If so skip on-disk list modification. 2784 */ 2785 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) > 2786 (le32_to_cpu(sbi->s_es->s_inodes_count))) { 2787 /* Insert this inode at the head of the on-disk orphan list */ 2788 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan); 2789 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 2790 dirty = true; 2791 } 2792 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan); 2793 mutex_unlock(&sbi->s_orphan_lock); 2794 2795 if (dirty) { 2796 err = ext4_handle_dirty_super(handle, sb); 2797 rc = ext4_mark_iloc_dirty(handle, inode, &iloc); 2798 if (!err) 2799 err = rc; 2800 if (err) { 2801 /* 2802 * We have to remove inode from in-memory list if 2803 * addition to on disk orphan list failed. Stray orphan 2804 * list entries can cause panics at unmount time. 2805 */ 2806 mutex_lock(&sbi->s_orphan_lock); 2807 list_del_init(&EXT4_I(inode)->i_orphan); 2808 mutex_unlock(&sbi->s_orphan_lock); 2809 } 2810 } 2811 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 2812 jbd_debug(4, "orphan inode %lu will point to %d\n", 2813 inode->i_ino, NEXT_ORPHAN(inode)); 2814 out: 2815 ext4_std_error(sb, err); 2816 return err; 2817 } 2818 2819 /* 2820 * ext4_orphan_del() removes an unlinked or truncated inode from the list 2821 * of such inodes stored on disk, because it is finally being cleaned up. 2822 */ 2823 int ext4_orphan_del(handle_t *handle, struct inode *inode) 2824 { 2825 struct list_head *prev; 2826 struct ext4_inode_info *ei = EXT4_I(inode); 2827 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 2828 __u32 ino_next; 2829 struct ext4_iloc iloc; 2830 int err = 0; 2831 2832 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS)) 2833 return 0; 2834 2835 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2836 !inode_is_locked(inode)); 2837 /* Do this quick check before taking global s_orphan_lock. */ 2838 if (list_empty(&ei->i_orphan)) 2839 return 0; 2840 2841 if (handle) { 2842 /* Grab inode buffer early before taking global s_orphan_lock */ 2843 err = ext4_reserve_inode_write(handle, inode, &iloc); 2844 } 2845 2846 mutex_lock(&sbi->s_orphan_lock); 2847 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 2848 2849 prev = ei->i_orphan.prev; 2850 list_del_init(&ei->i_orphan); 2851 2852 /* If we're on an error path, we may not have a valid 2853 * transaction handle with which to update the orphan list on 2854 * disk, but we still need to remove the inode from the linked 2855 * list in memory. */ 2856 if (!handle || err) { 2857 mutex_unlock(&sbi->s_orphan_lock); 2858 goto out_err; 2859 } 2860 2861 ino_next = NEXT_ORPHAN(inode); 2862 if (prev == &sbi->s_orphan) { 2863 jbd_debug(4, "superblock will point to %u\n", ino_next); 2864 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2865 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2866 if (err) { 2867 mutex_unlock(&sbi->s_orphan_lock); 2868 goto out_brelse; 2869 } 2870 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 2871 mutex_unlock(&sbi->s_orphan_lock); 2872 err = ext4_handle_dirty_super(handle, inode->i_sb); 2873 } else { 2874 struct ext4_iloc iloc2; 2875 struct inode *i_prev = 2876 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; 2877 2878 jbd_debug(4, "orphan inode %lu will point to %u\n", 2879 i_prev->i_ino, ino_next); 2880 err = ext4_reserve_inode_write(handle, i_prev, &iloc2); 2881 if (err) { 2882 mutex_unlock(&sbi->s_orphan_lock); 2883 goto out_brelse; 2884 } 2885 NEXT_ORPHAN(i_prev) = ino_next; 2886 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); 2887 mutex_unlock(&sbi->s_orphan_lock); 2888 } 2889 if (err) 2890 goto out_brelse; 2891 NEXT_ORPHAN(inode) = 0; 2892 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 2893 out_err: 2894 ext4_std_error(inode->i_sb, err); 2895 return err; 2896 2897 out_brelse: 2898 brelse(iloc.bh); 2899 goto out_err; 2900 } 2901 2902 static int ext4_rmdir(struct inode *dir, struct dentry *dentry) 2903 { 2904 int retval; 2905 struct inode *inode; 2906 struct buffer_head *bh; 2907 struct ext4_dir_entry_2 *de; 2908 handle_t *handle = NULL; 2909 2910 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 2911 return -EIO; 2912 2913 /* Initialize quotas before so that eventual writes go in 2914 * separate transaction */ 2915 retval = dquot_initialize(dir); 2916 if (retval) 2917 return retval; 2918 retval = dquot_initialize(d_inode(dentry)); 2919 if (retval) 2920 return retval; 2921 2922 retval = -ENOENT; 2923 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 2924 if (IS_ERR(bh)) 2925 return PTR_ERR(bh); 2926 if (!bh) 2927 goto end_rmdir; 2928 2929 inode = d_inode(dentry); 2930 2931 retval = -EFSCORRUPTED; 2932 if (le32_to_cpu(de->inode) != inode->i_ino) 2933 goto end_rmdir; 2934 2935 retval = -ENOTEMPTY; 2936 if (!ext4_empty_dir(inode)) 2937 goto end_rmdir; 2938 2939 handle = ext4_journal_start(dir, EXT4_HT_DIR, 2940 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 2941 if (IS_ERR(handle)) { 2942 retval = PTR_ERR(handle); 2943 handle = NULL; 2944 goto end_rmdir; 2945 } 2946 2947 if (IS_DIRSYNC(dir)) 2948 ext4_handle_sync(handle); 2949 2950 retval = ext4_delete_entry(handle, dir, de, bh); 2951 if (retval) 2952 goto end_rmdir; 2953 if (!EXT4_DIR_LINK_EMPTY(inode)) 2954 ext4_warning_inode(inode, 2955 "empty directory '%.*s' has too many links (%u)", 2956 dentry->d_name.len, dentry->d_name.name, 2957 inode->i_nlink); 2958 inode->i_version++; 2959 clear_nlink(inode); 2960 /* There's no need to set i_disksize: the fact that i_nlink is 2961 * zero will ensure that the right thing happens during any 2962 * recovery. */ 2963 inode->i_size = 0; 2964 ext4_orphan_add(handle, inode); 2965 inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); 2966 ext4_mark_inode_dirty(handle, inode); 2967 ext4_dec_count(handle, dir); 2968 ext4_update_dx_flag(dir); 2969 ext4_mark_inode_dirty(handle, dir); 2970 2971 end_rmdir: 2972 brelse(bh); 2973 if (handle) 2974 ext4_journal_stop(handle); 2975 return retval; 2976 } 2977 2978 static int ext4_unlink(struct inode *dir, struct dentry *dentry) 2979 { 2980 int retval; 2981 struct inode *inode; 2982 struct buffer_head *bh; 2983 struct ext4_dir_entry_2 *de; 2984 handle_t *handle = NULL; 2985 2986 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 2987 return -EIO; 2988 2989 trace_ext4_unlink_enter(dir, dentry); 2990 /* Initialize quotas before so that eventual writes go 2991 * in separate transaction */ 2992 retval = dquot_initialize(dir); 2993 if (retval) 2994 return retval; 2995 retval = dquot_initialize(d_inode(dentry)); 2996 if (retval) 2997 return retval; 2998 2999 retval = -ENOENT; 3000 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 3001 if (IS_ERR(bh)) 3002 return PTR_ERR(bh); 3003 if (!bh) 3004 goto end_unlink; 3005 3006 inode = d_inode(dentry); 3007 3008 retval = -EFSCORRUPTED; 3009 if (le32_to_cpu(de->inode) != inode->i_ino) 3010 goto end_unlink; 3011 3012 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3013 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 3014 if (IS_ERR(handle)) { 3015 retval = PTR_ERR(handle); 3016 handle = NULL; 3017 goto end_unlink; 3018 } 3019 3020 if (IS_DIRSYNC(dir)) 3021 ext4_handle_sync(handle); 3022 3023 if (inode->i_nlink == 0) { 3024 ext4_warning_inode(inode, "Deleting file '%.*s' with no links", 3025 dentry->d_name.len, dentry->d_name.name); 3026 set_nlink(inode, 1); 3027 } 3028 retval = ext4_delete_entry(handle, dir, de, bh); 3029 if (retval) 3030 goto end_unlink; 3031 dir->i_ctime = dir->i_mtime = current_time(dir); 3032 ext4_update_dx_flag(dir); 3033 ext4_mark_inode_dirty(handle, dir); 3034 drop_nlink(inode); 3035 if (!inode->i_nlink) 3036 ext4_orphan_add(handle, inode); 3037 inode->i_ctime = current_time(inode); 3038 ext4_mark_inode_dirty(handle, inode); 3039 3040 end_unlink: 3041 brelse(bh); 3042 if (handle) 3043 ext4_journal_stop(handle); 3044 trace_ext4_unlink_exit(dentry, retval); 3045 return retval; 3046 } 3047 3048 static int ext4_symlink(struct inode *dir, 3049 struct dentry *dentry, const char *symname) 3050 { 3051 handle_t *handle; 3052 struct inode *inode; 3053 int err, len = strlen(symname); 3054 int credits; 3055 bool encryption_required; 3056 struct fscrypt_str disk_link; 3057 struct fscrypt_symlink_data *sd = NULL; 3058 3059 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3060 return -EIO; 3061 3062 disk_link.len = len + 1; 3063 disk_link.name = (char *) symname; 3064 3065 encryption_required = (ext4_encrypted_inode(dir) || 3066 DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb))); 3067 if (encryption_required) { 3068 err = fscrypt_get_encryption_info(dir); 3069 if (err) 3070 return err; 3071 if (!fscrypt_has_encryption_key(dir)) 3072 return -ENOKEY; 3073 disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + 3074 sizeof(struct fscrypt_symlink_data)); 3075 sd = kzalloc(disk_link.len, GFP_KERNEL); 3076 if (!sd) 3077 return -ENOMEM; 3078 } 3079 3080 if (disk_link.len > dir->i_sb->s_blocksize) { 3081 err = -ENAMETOOLONG; 3082 goto err_free_sd; 3083 } 3084 3085 err = dquot_initialize(dir); 3086 if (err) 3087 goto err_free_sd; 3088 3089 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3090 /* 3091 * For non-fast symlinks, we just allocate inode and put it on 3092 * orphan list in the first transaction => we need bitmap, 3093 * group descriptor, sb, inode block, quota blocks, and 3094 * possibly selinux xattr blocks. 3095 */ 3096 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 3097 EXT4_XATTR_TRANS_BLOCKS; 3098 } else { 3099 /* 3100 * Fast symlink. We have to add entry to directory 3101 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), 3102 * allocate new inode (bitmap, group descriptor, inode block, 3103 * quota blocks, sb is already counted in previous macros). 3104 */ 3105 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3106 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3; 3107 } 3108 3109 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO, 3110 &dentry->d_name, 0, NULL, 3111 EXT4_HT_DIR, credits); 3112 handle = ext4_journal_current_handle(); 3113 if (IS_ERR(inode)) { 3114 if (handle) 3115 ext4_journal_stop(handle); 3116 err = PTR_ERR(inode); 3117 goto err_free_sd; 3118 } 3119 3120 if (encryption_required) { 3121 struct qstr istr; 3122 struct fscrypt_str ostr = 3123 FSTR_INIT(sd->encrypted_path, disk_link.len); 3124 3125 istr.name = (const unsigned char *) symname; 3126 istr.len = len; 3127 err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); 3128 if (err) 3129 goto err_drop_inode; 3130 sd->len = cpu_to_le16(ostr.len); 3131 disk_link.name = (char *) sd; 3132 inode->i_op = &ext4_encrypted_symlink_inode_operations; 3133 } 3134 3135 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3136 if (!encryption_required) 3137 inode->i_op = &ext4_symlink_inode_operations; 3138 inode_nohighmem(inode); 3139 ext4_set_aops(inode); 3140 /* 3141 * We cannot call page_symlink() with transaction started 3142 * because it calls into ext4_write_begin() which can wait 3143 * for transaction commit if we are running out of space 3144 * and thus we deadlock. So we have to stop transaction now 3145 * and restart it when symlink contents is written. 3146 * 3147 * To keep fs consistent in case of crash, we have to put inode 3148 * to orphan list in the mean time. 3149 */ 3150 drop_nlink(inode); 3151 err = ext4_orphan_add(handle, inode); 3152 ext4_journal_stop(handle); 3153 handle = NULL; 3154 if (err) 3155 goto err_drop_inode; 3156 err = __page_symlink(inode, disk_link.name, disk_link.len, 1); 3157 if (err) 3158 goto err_drop_inode; 3159 /* 3160 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS 3161 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified 3162 */ 3163 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3164 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3165 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); 3166 if (IS_ERR(handle)) { 3167 err = PTR_ERR(handle); 3168 handle = NULL; 3169 goto err_drop_inode; 3170 } 3171 set_nlink(inode, 1); 3172 err = ext4_orphan_del(handle, inode); 3173 if (err) 3174 goto err_drop_inode; 3175 } else { 3176 /* clear the extent format for fast symlink */ 3177 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); 3178 if (!encryption_required) { 3179 inode->i_op = &ext4_fast_symlink_inode_operations; 3180 inode->i_link = (char *)&EXT4_I(inode)->i_data; 3181 } 3182 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name, 3183 disk_link.len); 3184 inode->i_size = disk_link.len - 1; 3185 } 3186 EXT4_I(inode)->i_disksize = inode->i_size; 3187 err = ext4_add_nondir(handle, dentry, inode); 3188 if (!err && IS_DIRSYNC(dir)) 3189 ext4_handle_sync(handle); 3190 3191 if (handle) 3192 ext4_journal_stop(handle); 3193 kfree(sd); 3194 return err; 3195 err_drop_inode: 3196 if (handle) 3197 ext4_journal_stop(handle); 3198 clear_nlink(inode); 3199 unlock_new_inode(inode); 3200 iput(inode); 3201 err_free_sd: 3202 kfree(sd); 3203 return err; 3204 } 3205 3206 static int ext4_link(struct dentry *old_dentry, 3207 struct inode *dir, struct dentry *dentry) 3208 { 3209 handle_t *handle; 3210 struct inode *inode = d_inode(old_dentry); 3211 int err, retries = 0; 3212 3213 if (inode->i_nlink >= EXT4_LINK_MAX) 3214 return -EMLINK; 3215 3216 err = fscrypt_prepare_link(old_dentry, dir, dentry); 3217 if (err) 3218 return err; 3219 3220 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) && 3221 (!projid_eq(EXT4_I(dir)->i_projid, 3222 EXT4_I(old_dentry->d_inode)->i_projid))) 3223 return -EXDEV; 3224 3225 err = dquot_initialize(dir); 3226 if (err) 3227 return err; 3228 3229 retry: 3230 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3231 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3232 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1); 3233 if (IS_ERR(handle)) 3234 return PTR_ERR(handle); 3235 3236 if (IS_DIRSYNC(dir)) 3237 ext4_handle_sync(handle); 3238 3239 inode->i_ctime = current_time(inode); 3240 ext4_inc_count(handle, inode); 3241 ihold(inode); 3242 3243 err = ext4_add_entry(handle, dentry, inode); 3244 if (!err) { 3245 ext4_mark_inode_dirty(handle, inode); 3246 /* this can happen only for tmpfile being 3247 * linked the first time 3248 */ 3249 if (inode->i_nlink == 1) 3250 ext4_orphan_del(handle, inode); 3251 d_instantiate(dentry, inode); 3252 } else { 3253 drop_nlink(inode); 3254 iput(inode); 3255 } 3256 ext4_journal_stop(handle); 3257 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 3258 goto retry; 3259 return err; 3260 } 3261 3262 3263 /* 3264 * Try to find buffer head where contains the parent block. 3265 * It should be the inode block if it is inlined or the 1st block 3266 * if it is a normal dir. 3267 */ 3268 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, 3269 struct inode *inode, 3270 int *retval, 3271 struct ext4_dir_entry_2 **parent_de, 3272 int *inlined) 3273 { 3274 struct buffer_head *bh; 3275 3276 if (!ext4_has_inline_data(inode)) { 3277 bh = ext4_read_dirblock(inode, 0, EITHER); 3278 if (IS_ERR(bh)) { 3279 *retval = PTR_ERR(bh); 3280 return NULL; 3281 } 3282 *parent_de = ext4_next_entry( 3283 (struct ext4_dir_entry_2 *)bh->b_data, 3284 inode->i_sb->s_blocksize); 3285 return bh; 3286 } 3287 3288 *inlined = 1; 3289 return ext4_get_first_inline_block(inode, parent_de, retval); 3290 } 3291 3292 struct ext4_renament { 3293 struct inode *dir; 3294 struct dentry *dentry; 3295 struct inode *inode; 3296 bool is_dir; 3297 int dir_nlink_delta; 3298 3299 /* entry for "dentry" */ 3300 struct buffer_head *bh; 3301 struct ext4_dir_entry_2 *de; 3302 int inlined; 3303 3304 /* entry for ".." in inode if it's a directory */ 3305 struct buffer_head *dir_bh; 3306 struct ext4_dir_entry_2 *parent_de; 3307 int dir_inlined; 3308 }; 3309 3310 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) 3311 { 3312 int retval; 3313 3314 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, 3315 &retval, &ent->parent_de, 3316 &ent->dir_inlined); 3317 if (!ent->dir_bh) 3318 return retval; 3319 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) 3320 return -EFSCORRUPTED; 3321 BUFFER_TRACE(ent->dir_bh, "get_write_access"); 3322 return ext4_journal_get_write_access(handle, ent->dir_bh); 3323 } 3324 3325 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, 3326 unsigned dir_ino) 3327 { 3328 int retval; 3329 3330 ent->parent_de->inode = cpu_to_le32(dir_ino); 3331 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); 3332 if (!ent->dir_inlined) { 3333 if (is_dx(ent->inode)) { 3334 retval = ext4_handle_dirty_dx_node(handle, 3335 ent->inode, 3336 ent->dir_bh); 3337 } else { 3338 retval = ext4_handle_dirty_dirent_node(handle, 3339 ent->inode, 3340 ent->dir_bh); 3341 } 3342 } else { 3343 retval = ext4_mark_inode_dirty(handle, ent->inode); 3344 } 3345 if (retval) { 3346 ext4_std_error(ent->dir->i_sb, retval); 3347 return retval; 3348 } 3349 return 0; 3350 } 3351 3352 static int ext4_setent(handle_t *handle, struct ext4_renament *ent, 3353 unsigned ino, unsigned file_type) 3354 { 3355 int retval; 3356 3357 BUFFER_TRACE(ent->bh, "get write access"); 3358 retval = ext4_journal_get_write_access(handle, ent->bh); 3359 if (retval) 3360 return retval; 3361 ent->de->inode = cpu_to_le32(ino); 3362 if (ext4_has_feature_filetype(ent->dir->i_sb)) 3363 ent->de->file_type = file_type; 3364 ent->dir->i_version++; 3365 ent->dir->i_ctime = ent->dir->i_mtime = 3366 current_time(ent->dir); 3367 ext4_mark_inode_dirty(handle, ent->dir); 3368 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); 3369 if (!ent->inlined) { 3370 retval = ext4_handle_dirty_dirent_node(handle, 3371 ent->dir, ent->bh); 3372 if (unlikely(retval)) { 3373 ext4_std_error(ent->dir->i_sb, retval); 3374 return retval; 3375 } 3376 } 3377 brelse(ent->bh); 3378 ent->bh = NULL; 3379 3380 return 0; 3381 } 3382 3383 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, 3384 const struct qstr *d_name) 3385 { 3386 int retval = -ENOENT; 3387 struct buffer_head *bh; 3388 struct ext4_dir_entry_2 *de; 3389 3390 bh = ext4_find_entry(dir, d_name, &de, NULL); 3391 if (IS_ERR(bh)) 3392 return PTR_ERR(bh); 3393 if (bh) { 3394 retval = ext4_delete_entry(handle, dir, de, bh); 3395 brelse(bh); 3396 } 3397 return retval; 3398 } 3399 3400 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent, 3401 int force_reread) 3402 { 3403 int retval; 3404 /* 3405 * ent->de could have moved from under us during htree split, so make 3406 * sure that we are deleting the right entry. We might also be pointing 3407 * to a stale entry in the unused part of ent->bh so just checking inum 3408 * and the name isn't enough. 3409 */ 3410 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || 3411 ent->de->name_len != ent->dentry->d_name.len || 3412 strncmp(ent->de->name, ent->dentry->d_name.name, 3413 ent->de->name_len) || 3414 force_reread) { 3415 retval = ext4_find_delete_entry(handle, ent->dir, 3416 &ent->dentry->d_name); 3417 } else { 3418 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); 3419 if (retval == -ENOENT) { 3420 retval = ext4_find_delete_entry(handle, ent->dir, 3421 &ent->dentry->d_name); 3422 } 3423 } 3424 3425 if (retval) { 3426 ext4_warning_inode(ent->dir, 3427 "Deleting old file: nlink %d, error=%d", 3428 ent->dir->i_nlink, retval); 3429 } 3430 } 3431 3432 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) 3433 { 3434 if (ent->dir_nlink_delta) { 3435 if (ent->dir_nlink_delta == -1) 3436 ext4_dec_count(handle, ent->dir); 3437 else 3438 ext4_inc_count(handle, ent->dir); 3439 ext4_mark_inode_dirty(handle, ent->dir); 3440 } 3441 } 3442 3443 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, 3444 int credits, handle_t **h) 3445 { 3446 struct inode *wh; 3447 handle_t *handle; 3448 int retries = 0; 3449 3450 /* 3451 * for inode block, sb block, group summaries, 3452 * and inode bitmap 3453 */ 3454 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + 3455 EXT4_XATTR_TRANS_BLOCKS + 4); 3456 retry: 3457 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, 3458 &ent->dentry->d_name, 0, NULL, 3459 EXT4_HT_DIR, credits); 3460 3461 handle = ext4_journal_current_handle(); 3462 if (IS_ERR(wh)) { 3463 if (handle) 3464 ext4_journal_stop(handle); 3465 if (PTR_ERR(wh) == -ENOSPC && 3466 ext4_should_retry_alloc(ent->dir->i_sb, &retries)) 3467 goto retry; 3468 } else { 3469 *h = handle; 3470 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); 3471 wh->i_op = &ext4_special_inode_operations; 3472 } 3473 return wh; 3474 } 3475 3476 /* 3477 * Anybody can rename anything with this: the permission checks are left to the 3478 * higher-level routines. 3479 * 3480 * n.b. old_{dentry,inode) refers to the source dentry/inode 3481 * while new_{dentry,inode) refers to the destination dentry/inode 3482 * This comes from rename(const char *oldpath, const char *newpath) 3483 */ 3484 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, 3485 struct inode *new_dir, struct dentry *new_dentry, 3486 unsigned int flags) 3487 { 3488 handle_t *handle = NULL; 3489 struct ext4_renament old = { 3490 .dir = old_dir, 3491 .dentry = old_dentry, 3492 .inode = d_inode(old_dentry), 3493 }; 3494 struct ext4_renament new = { 3495 .dir = new_dir, 3496 .dentry = new_dentry, 3497 .inode = d_inode(new_dentry), 3498 }; 3499 int force_reread; 3500 int retval; 3501 struct inode *whiteout = NULL; 3502 int credits; 3503 u8 old_file_type; 3504 3505 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && 3506 (!projid_eq(EXT4_I(new_dir)->i_projid, 3507 EXT4_I(old_dentry->d_inode)->i_projid))) 3508 return -EXDEV; 3509 3510 retval = dquot_initialize(old.dir); 3511 if (retval) 3512 return retval; 3513 retval = dquot_initialize(new.dir); 3514 if (retval) 3515 return retval; 3516 3517 /* Initialize quotas before so that eventual writes go 3518 * in separate transaction */ 3519 if (new.inode) { 3520 retval = dquot_initialize(new.inode); 3521 if (retval) 3522 return retval; 3523 } 3524 3525 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); 3526 if (IS_ERR(old.bh)) 3527 return PTR_ERR(old.bh); 3528 /* 3529 * Check for inode number is _not_ due to possible IO errors. 3530 * We might rmdir the source, keep it as pwd of some process 3531 * and merrily kill the link to whatever was created under the 3532 * same name. Goodbye sticky bit ;-< 3533 */ 3534 retval = -ENOENT; 3535 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3536 goto end_rename; 3537 3538 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3539 &new.de, &new.inlined); 3540 if (IS_ERR(new.bh)) { 3541 retval = PTR_ERR(new.bh); 3542 new.bh = NULL; 3543 goto end_rename; 3544 } 3545 if (new.bh) { 3546 if (!new.inode) { 3547 brelse(new.bh); 3548 new.bh = NULL; 3549 } 3550 } 3551 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) 3552 ext4_alloc_da_blocks(old.inode); 3553 3554 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3555 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); 3556 if (!(flags & RENAME_WHITEOUT)) { 3557 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); 3558 if (IS_ERR(handle)) { 3559 retval = PTR_ERR(handle); 3560 handle = NULL; 3561 goto end_rename; 3562 } 3563 } else { 3564 whiteout = ext4_whiteout_for_rename(&old, credits, &handle); 3565 if (IS_ERR(whiteout)) { 3566 retval = PTR_ERR(whiteout); 3567 whiteout = NULL; 3568 goto end_rename; 3569 } 3570 } 3571 3572 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3573 ext4_handle_sync(handle); 3574 3575 if (S_ISDIR(old.inode->i_mode)) { 3576 if (new.inode) { 3577 retval = -ENOTEMPTY; 3578 if (!ext4_empty_dir(new.inode)) 3579 goto end_rename; 3580 } else { 3581 retval = -EMLINK; 3582 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) 3583 goto end_rename; 3584 } 3585 retval = ext4_rename_dir_prepare(handle, &old); 3586 if (retval) 3587 goto end_rename; 3588 } 3589 /* 3590 * If we're renaming a file within an inline_data dir and adding or 3591 * setting the new dirent causes a conversion from inline_data to 3592 * extents/blockmap, we need to force the dirent delete code to 3593 * re-read the directory, or else we end up trying to delete a dirent 3594 * from what is now the extent tree root (or a block map). 3595 */ 3596 force_reread = (new.dir->i_ino == old.dir->i_ino && 3597 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); 3598 3599 old_file_type = old.de->file_type; 3600 if (whiteout) { 3601 /* 3602 * Do this before adding a new entry, so the old entry is sure 3603 * to be still pointing to the valid old entry. 3604 */ 3605 retval = ext4_setent(handle, &old, whiteout->i_ino, 3606 EXT4_FT_CHRDEV); 3607 if (retval) 3608 goto end_rename; 3609 ext4_mark_inode_dirty(handle, whiteout); 3610 } 3611 if (!new.bh) { 3612 retval = ext4_add_entry(handle, new.dentry, old.inode); 3613 if (retval) 3614 goto end_rename; 3615 } else { 3616 retval = ext4_setent(handle, &new, 3617 old.inode->i_ino, old_file_type); 3618 if (retval) 3619 goto end_rename; 3620 } 3621 if (force_reread) 3622 force_reread = !ext4_test_inode_flag(new.dir, 3623 EXT4_INODE_INLINE_DATA); 3624 3625 /* 3626 * Like most other Unix systems, set the ctime for inodes on a 3627 * rename. 3628 */ 3629 old.inode->i_ctime = current_time(old.inode); 3630 ext4_mark_inode_dirty(handle, old.inode); 3631 3632 if (!whiteout) { 3633 /* 3634 * ok, that's it 3635 */ 3636 ext4_rename_delete(handle, &old, force_reread); 3637 } 3638 3639 if (new.inode) { 3640 ext4_dec_count(handle, new.inode); 3641 new.inode->i_ctime = current_time(new.inode); 3642 } 3643 old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir); 3644 ext4_update_dx_flag(old.dir); 3645 if (old.dir_bh) { 3646 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3647 if (retval) 3648 goto end_rename; 3649 3650 ext4_dec_count(handle, old.dir); 3651 if (new.inode) { 3652 /* checked ext4_empty_dir above, can't have another 3653 * parent, ext4_dec_count() won't work for many-linked 3654 * dirs */ 3655 clear_nlink(new.inode); 3656 } else { 3657 ext4_inc_count(handle, new.dir); 3658 ext4_update_dx_flag(new.dir); 3659 ext4_mark_inode_dirty(handle, new.dir); 3660 } 3661 } 3662 ext4_mark_inode_dirty(handle, old.dir); 3663 if (new.inode) { 3664 ext4_mark_inode_dirty(handle, new.inode); 3665 if (!new.inode->i_nlink) 3666 ext4_orphan_add(handle, new.inode); 3667 } 3668 retval = 0; 3669 3670 end_rename: 3671 brelse(old.dir_bh); 3672 brelse(old.bh); 3673 brelse(new.bh); 3674 if (whiteout) { 3675 if (retval) 3676 drop_nlink(whiteout); 3677 unlock_new_inode(whiteout); 3678 iput(whiteout); 3679 } 3680 if (handle) 3681 ext4_journal_stop(handle); 3682 return retval; 3683 } 3684 3685 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, 3686 struct inode *new_dir, struct dentry *new_dentry) 3687 { 3688 handle_t *handle = NULL; 3689 struct ext4_renament old = { 3690 .dir = old_dir, 3691 .dentry = old_dentry, 3692 .inode = d_inode(old_dentry), 3693 }; 3694 struct ext4_renament new = { 3695 .dir = new_dir, 3696 .dentry = new_dentry, 3697 .inode = d_inode(new_dentry), 3698 }; 3699 u8 new_file_type; 3700 int retval; 3701 struct timespec ctime; 3702 3703 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) && 3704 !projid_eq(EXT4_I(new_dir)->i_projid, 3705 EXT4_I(old_dentry->d_inode)->i_projid)) || 3706 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) && 3707 !projid_eq(EXT4_I(old_dir)->i_projid, 3708 EXT4_I(new_dentry->d_inode)->i_projid))) 3709 return -EXDEV; 3710 3711 retval = dquot_initialize(old.dir); 3712 if (retval) 3713 return retval; 3714 retval = dquot_initialize(new.dir); 3715 if (retval) 3716 return retval; 3717 3718 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, 3719 &old.de, &old.inlined); 3720 if (IS_ERR(old.bh)) 3721 return PTR_ERR(old.bh); 3722 /* 3723 * Check for inode number is _not_ due to possible IO errors. 3724 * We might rmdir the source, keep it as pwd of some process 3725 * and merrily kill the link to whatever was created under the 3726 * same name. Goodbye sticky bit ;-< 3727 */ 3728 retval = -ENOENT; 3729 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3730 goto end_rename; 3731 3732 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3733 &new.de, &new.inlined); 3734 if (IS_ERR(new.bh)) { 3735 retval = PTR_ERR(new.bh); 3736 new.bh = NULL; 3737 goto end_rename; 3738 } 3739 3740 /* RENAME_EXCHANGE case: old *and* new must both exist */ 3741 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) 3742 goto end_rename; 3743 3744 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, 3745 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3746 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); 3747 if (IS_ERR(handle)) { 3748 retval = PTR_ERR(handle); 3749 handle = NULL; 3750 goto end_rename; 3751 } 3752 3753 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3754 ext4_handle_sync(handle); 3755 3756 if (S_ISDIR(old.inode->i_mode)) { 3757 old.is_dir = true; 3758 retval = ext4_rename_dir_prepare(handle, &old); 3759 if (retval) 3760 goto end_rename; 3761 } 3762 if (S_ISDIR(new.inode->i_mode)) { 3763 new.is_dir = true; 3764 retval = ext4_rename_dir_prepare(handle, &new); 3765 if (retval) 3766 goto end_rename; 3767 } 3768 3769 /* 3770 * Other than the special case of overwriting a directory, parents' 3771 * nlink only needs to be modified if this is a cross directory rename. 3772 */ 3773 if (old.dir != new.dir && old.is_dir != new.is_dir) { 3774 old.dir_nlink_delta = old.is_dir ? -1 : 1; 3775 new.dir_nlink_delta = -old.dir_nlink_delta; 3776 retval = -EMLINK; 3777 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || 3778 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) 3779 goto end_rename; 3780 } 3781 3782 new_file_type = new.de->file_type; 3783 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); 3784 if (retval) 3785 goto end_rename; 3786 3787 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); 3788 if (retval) 3789 goto end_rename; 3790 3791 /* 3792 * Like most other Unix systems, set the ctime for inodes on a 3793 * rename. 3794 */ 3795 ctime = current_time(old.inode); 3796 old.inode->i_ctime = ctime; 3797 new.inode->i_ctime = ctime; 3798 ext4_mark_inode_dirty(handle, old.inode); 3799 ext4_mark_inode_dirty(handle, new.inode); 3800 3801 if (old.dir_bh) { 3802 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3803 if (retval) 3804 goto end_rename; 3805 } 3806 if (new.dir_bh) { 3807 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); 3808 if (retval) 3809 goto end_rename; 3810 } 3811 ext4_update_dir_count(handle, &old); 3812 ext4_update_dir_count(handle, &new); 3813 retval = 0; 3814 3815 end_rename: 3816 brelse(old.dir_bh); 3817 brelse(new.dir_bh); 3818 brelse(old.bh); 3819 brelse(new.bh); 3820 if (handle) 3821 ext4_journal_stop(handle); 3822 return retval; 3823 } 3824 3825 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, 3826 struct inode *new_dir, struct dentry *new_dentry, 3827 unsigned int flags) 3828 { 3829 int err; 3830 3831 if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb)))) 3832 return -EIO; 3833 3834 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 3835 return -EINVAL; 3836 3837 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry, 3838 flags); 3839 if (err) 3840 return err; 3841 3842 if (flags & RENAME_EXCHANGE) { 3843 return ext4_cross_rename(old_dir, old_dentry, 3844 new_dir, new_dentry); 3845 } 3846 3847 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 3848 } 3849 3850 /* 3851 * directories can handle most operations... 3852 */ 3853 const struct inode_operations ext4_dir_inode_operations = { 3854 .create = ext4_create, 3855 .lookup = ext4_lookup, 3856 .link = ext4_link, 3857 .unlink = ext4_unlink, 3858 .symlink = ext4_symlink, 3859 .mkdir = ext4_mkdir, 3860 .rmdir = ext4_rmdir, 3861 .mknod = ext4_mknod, 3862 .tmpfile = ext4_tmpfile, 3863 .rename = ext4_rename2, 3864 .setattr = ext4_setattr, 3865 .getattr = ext4_getattr, 3866 .listxattr = ext4_listxattr, 3867 .get_acl = ext4_get_acl, 3868 .set_acl = ext4_set_acl, 3869 .fiemap = ext4_fiemap, 3870 }; 3871 3872 const struct inode_operations ext4_special_inode_operations = { 3873 .setattr = ext4_setattr, 3874 .getattr = ext4_getattr, 3875 .listxattr = ext4_listxattr, 3876 .get_acl = ext4_get_acl, 3877 .set_acl = ext4_set_acl, 3878 }; 3879