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