1 /* 2 * linux/fs/ext4/namei.c 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 * 9 * from 10 * 11 * linux/fs/minix/namei.c 12 * 13 * Copyright (C) 1991, 1992 Linus Torvalds 14 * 15 * Big-endian to little-endian byte-swapping/bitmaps by 16 * David S. Miller (davem@caip.rutgers.edu), 1995 17 * Directory entry file type support and forward compatibility hooks 18 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998 19 * Hash Tree Directory indexing (c) 20 * Daniel Phillips, 2001 21 * Hash Tree Directory indexing porting 22 * Christopher Li, 2002 23 * Hash Tree Directory indexing cleanup 24 * Theodore Ts'o, 2002 25 */ 26 27 #include <linux/fs.h> 28 #include <linux/pagemap.h> 29 #include <linux/time.h> 30 #include <linux/fcntl.h> 31 #include <linux/stat.h> 32 #include <linux/string.h> 33 #include <linux/quotaops.h> 34 #include <linux/buffer_head.h> 35 #include <linux/bio.h> 36 #include "ext4.h" 37 #include "ext4_jbd2.h" 38 39 #include "xattr.h" 40 #include "acl.h" 41 42 #include <trace/events/ext4.h> 43 /* 44 * define how far ahead to read directories while searching them. 45 */ 46 #define NAMEI_RA_CHUNKS 2 47 #define NAMEI_RA_BLOCKS 4 48 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) 49 50 static struct buffer_head *ext4_append(handle_t *handle, 51 struct inode *inode, 52 ext4_lblk_t *block) 53 { 54 struct buffer_head *bh; 55 int err; 56 57 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb && 58 ((inode->i_size >> 10) >= 59 EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) 60 return ERR_PTR(-ENOSPC); 61 62 *block = inode->i_size >> inode->i_sb->s_blocksize_bits; 63 64 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE); 65 if (IS_ERR(bh)) 66 return bh; 67 inode->i_size += inode->i_sb->s_blocksize; 68 EXT4_I(inode)->i_disksize = inode->i_size; 69 BUFFER_TRACE(bh, "get_write_access"); 70 err = ext4_journal_get_write_access(handle, bh); 71 if (err) { 72 brelse(bh); 73 ext4_std_error(inode->i_sb, err); 74 return ERR_PTR(err); 75 } 76 return bh; 77 } 78 79 static int ext4_dx_csum_verify(struct inode *inode, 80 struct ext4_dir_entry *dirent); 81 82 typedef enum { 83 EITHER, INDEX, DIRENT 84 } dirblock_type_t; 85 86 #define ext4_read_dirblock(inode, block, type) \ 87 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__) 88 89 static struct buffer_head *__ext4_read_dirblock(struct inode *inode, 90 ext4_lblk_t block, 91 dirblock_type_t type, 92 const char *func, 93 unsigned int line) 94 { 95 struct buffer_head *bh; 96 struct ext4_dir_entry *dirent; 97 int is_dx_block = 0; 98 99 bh = ext4_bread(NULL, inode, block, 0); 100 if (IS_ERR(bh)) { 101 __ext4_warning(inode->i_sb, func, line, 102 "inode #%lu: lblock %lu: comm %s: " 103 "error %ld reading directory block", 104 inode->i_ino, (unsigned long)block, 105 current->comm, PTR_ERR(bh)); 106 107 return bh; 108 } 109 if (!bh) { 110 ext4_error_inode(inode, func, line, block, 111 "Directory hole found"); 112 return ERR_PTR(-EFSCORRUPTED); 113 } 114 dirent = (struct ext4_dir_entry *) bh->b_data; 115 /* Determine whether or not we have an index block */ 116 if (is_dx(inode)) { 117 if (block == 0) 118 is_dx_block = 1; 119 else if (ext4_rec_len_from_disk(dirent->rec_len, 120 inode->i_sb->s_blocksize) == 121 inode->i_sb->s_blocksize) 122 is_dx_block = 1; 123 } 124 if (!is_dx_block && type == INDEX) { 125 ext4_error_inode(inode, func, line, block, 126 "directory leaf block found instead of index block"); 127 return ERR_PTR(-EFSCORRUPTED); 128 } 129 if (!ext4_has_metadata_csum(inode->i_sb) || 130 buffer_verified(bh)) 131 return bh; 132 133 /* 134 * An empty leaf block can get mistaken for a index block; for 135 * this reason, we can only check the index checksum when the 136 * caller is sure it should be an index block. 137 */ 138 if (is_dx_block && type == INDEX) { 139 if (ext4_dx_csum_verify(inode, dirent)) 140 set_buffer_verified(bh); 141 else { 142 ext4_error_inode(inode, func, line, block, 143 "Directory index failed checksum"); 144 brelse(bh); 145 return ERR_PTR(-EFSBADCRC); 146 } 147 } 148 if (!is_dx_block) { 149 if (ext4_dirent_csum_verify(inode, dirent)) 150 set_buffer_verified(bh); 151 else { 152 ext4_error_inode(inode, func, line, block, 153 "Directory block failed checksum"); 154 brelse(bh); 155 return ERR_PTR(-EFSBADCRC); 156 } 157 } 158 return bh; 159 } 160 161 #ifndef assert 162 #define assert(test) J_ASSERT(test) 163 #endif 164 165 #ifdef DX_DEBUG 166 #define dxtrace(command) command 167 #else 168 #define dxtrace(command) 169 #endif 170 171 struct fake_dirent 172 { 173 __le32 inode; 174 __le16 rec_len; 175 u8 name_len; 176 u8 file_type; 177 }; 178 179 struct dx_countlimit 180 { 181 __le16 limit; 182 __le16 count; 183 }; 184 185 struct dx_entry 186 { 187 __le32 hash; 188 __le32 block; 189 }; 190 191 /* 192 * dx_root_info is laid out so that if it should somehow get overlaid by a 193 * dirent the two low bits of the hash version will be zero. Therefore, the 194 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 195 */ 196 197 struct dx_root 198 { 199 struct fake_dirent dot; 200 char dot_name[4]; 201 struct fake_dirent dotdot; 202 char dotdot_name[4]; 203 struct dx_root_info 204 { 205 __le32 reserved_zero; 206 u8 hash_version; 207 u8 info_length; /* 8 */ 208 u8 indirect_levels; 209 u8 unused_flags; 210 } 211 info; 212 struct dx_entry entries[0]; 213 }; 214 215 struct dx_node 216 { 217 struct fake_dirent fake; 218 struct dx_entry entries[0]; 219 }; 220 221 222 struct dx_frame 223 { 224 struct buffer_head *bh; 225 struct dx_entry *entries; 226 struct dx_entry *at; 227 }; 228 229 struct dx_map_entry 230 { 231 u32 hash; 232 u16 offs; 233 u16 size; 234 }; 235 236 /* 237 * This goes at the end of each htree block. 238 */ 239 struct dx_tail { 240 u32 dt_reserved; 241 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */ 242 }; 243 244 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry); 245 static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value); 246 static inline unsigned dx_get_hash(struct dx_entry *entry); 247 static void dx_set_hash(struct dx_entry *entry, unsigned value); 248 static unsigned dx_get_count(struct dx_entry *entries); 249 static unsigned dx_get_limit(struct dx_entry *entries); 250 static void dx_set_count(struct dx_entry *entries, unsigned value); 251 static void dx_set_limit(struct dx_entry *entries, unsigned value); 252 static unsigned dx_root_limit(struct inode *dir, unsigned infosize); 253 static unsigned dx_node_limit(struct inode *dir); 254 static struct dx_frame *dx_probe(struct ext4_filename *fname, 255 struct inode *dir, 256 struct dx_hash_info *hinfo, 257 struct dx_frame *frame); 258 static void dx_release(struct dx_frame *frames); 259 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 260 unsigned blocksize, struct dx_hash_info *hinfo, 261 struct dx_map_entry map[]); 262 static void dx_sort_map(struct dx_map_entry *map, unsigned count); 263 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to, 264 struct dx_map_entry *offsets, int count, unsigned blocksize); 265 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize); 266 static void dx_insert_block(struct dx_frame *frame, 267 u32 hash, ext4_lblk_t block); 268 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 269 struct dx_frame *frame, 270 struct dx_frame *frames, 271 __u32 *start_hash); 272 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 273 struct ext4_filename *fname, 274 struct ext4_dir_entry_2 **res_dir); 275 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 276 struct inode *dir, struct inode *inode); 277 278 /* checksumming functions */ 279 void initialize_dirent_tail(struct ext4_dir_entry_tail *t, 280 unsigned int blocksize) 281 { 282 memset(t, 0, sizeof(struct ext4_dir_entry_tail)); 283 t->det_rec_len = ext4_rec_len_to_disk( 284 sizeof(struct ext4_dir_entry_tail), blocksize); 285 t->det_reserved_ft = EXT4_FT_DIR_CSUM; 286 } 287 288 /* Walk through a dirent block to find a checksum "dirent" at the tail */ 289 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode, 290 struct ext4_dir_entry *de) 291 { 292 struct ext4_dir_entry_tail *t; 293 294 #ifdef PARANOID 295 struct ext4_dir_entry *d, *top; 296 297 d = de; 298 top = (struct ext4_dir_entry *)(((void *)de) + 299 (EXT4_BLOCK_SIZE(inode->i_sb) - 300 sizeof(struct ext4_dir_entry_tail))); 301 while (d < top && d->rec_len) 302 d = (struct ext4_dir_entry *)(((void *)d) + 303 le16_to_cpu(d->rec_len)); 304 305 if (d != top) 306 return NULL; 307 308 t = (struct ext4_dir_entry_tail *)d; 309 #else 310 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb)); 311 #endif 312 313 if (t->det_reserved_zero1 || 314 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) || 315 t->det_reserved_zero2 || 316 t->det_reserved_ft != EXT4_FT_DIR_CSUM) 317 return NULL; 318 319 return t; 320 } 321 322 static __le32 ext4_dirent_csum(struct inode *inode, 323 struct ext4_dir_entry *dirent, int size) 324 { 325 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 326 struct ext4_inode_info *ei = EXT4_I(inode); 327 __u32 csum; 328 329 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 330 return cpu_to_le32(csum); 331 } 332 333 #define warn_no_space_for_csum(inode) \ 334 __warn_no_space_for_csum((inode), __func__, __LINE__) 335 336 static void __warn_no_space_for_csum(struct inode *inode, const char *func, 337 unsigned int line) 338 { 339 __ext4_warning_inode(inode, func, line, 340 "No space for directory leaf checksum. Please run e2fsck -D."); 341 } 342 343 int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent) 344 { 345 struct ext4_dir_entry_tail *t; 346 347 if (!ext4_has_metadata_csum(inode->i_sb)) 348 return 1; 349 350 t = get_dirent_tail(inode, dirent); 351 if (!t) { 352 warn_no_space_for_csum(inode); 353 return 0; 354 } 355 356 if (t->det_checksum != ext4_dirent_csum(inode, dirent, 357 (void *)t - (void *)dirent)) 358 return 0; 359 360 return 1; 361 } 362 363 static void ext4_dirent_csum_set(struct inode *inode, 364 struct ext4_dir_entry *dirent) 365 { 366 struct ext4_dir_entry_tail *t; 367 368 if (!ext4_has_metadata_csum(inode->i_sb)) 369 return; 370 371 t = get_dirent_tail(inode, dirent); 372 if (!t) { 373 warn_no_space_for_csum(inode); 374 return; 375 } 376 377 t->det_checksum = ext4_dirent_csum(inode, dirent, 378 (void *)t - (void *)dirent); 379 } 380 381 int ext4_handle_dirty_dirent_node(handle_t *handle, 382 struct inode *inode, 383 struct buffer_head *bh) 384 { 385 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 386 return ext4_handle_dirty_metadata(handle, inode, bh); 387 } 388 389 static struct dx_countlimit *get_dx_countlimit(struct inode *inode, 390 struct ext4_dir_entry *dirent, 391 int *offset) 392 { 393 struct ext4_dir_entry *dp; 394 struct dx_root_info *root; 395 int count_offset; 396 397 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb)) 398 count_offset = 8; 399 else if (le16_to_cpu(dirent->rec_len) == 12) { 400 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12); 401 if (le16_to_cpu(dp->rec_len) != 402 EXT4_BLOCK_SIZE(inode->i_sb) - 12) 403 return NULL; 404 root = (struct dx_root_info *)(((void *)dp + 12)); 405 if (root->reserved_zero || 406 root->info_length != sizeof(struct dx_root_info)) 407 return NULL; 408 count_offset = 32; 409 } else 410 return NULL; 411 412 if (offset) 413 *offset = count_offset; 414 return (struct dx_countlimit *)(((void *)dirent) + count_offset); 415 } 416 417 static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent, 418 int count_offset, int count, struct dx_tail *t) 419 { 420 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 421 struct ext4_inode_info *ei = EXT4_I(inode); 422 __u32 csum; 423 int size; 424 __u32 dummy_csum = 0; 425 int offset = offsetof(struct dx_tail, dt_checksum); 426 427 size = count_offset + (count * sizeof(struct dx_entry)); 428 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 429 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset); 430 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); 431 432 return cpu_to_le32(csum); 433 } 434 435 static int ext4_dx_csum_verify(struct inode *inode, 436 struct ext4_dir_entry *dirent) 437 { 438 struct dx_countlimit *c; 439 struct dx_tail *t; 440 int count_offset, limit, count; 441 442 if (!ext4_has_metadata_csum(inode->i_sb)) 443 return 1; 444 445 c = get_dx_countlimit(inode, dirent, &count_offset); 446 if (!c) { 447 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 448 return 0; 449 } 450 limit = le16_to_cpu(c->limit); 451 count = le16_to_cpu(c->count); 452 if (count_offset + (limit * sizeof(struct dx_entry)) > 453 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 454 warn_no_space_for_csum(inode); 455 return 0; 456 } 457 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 458 459 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset, 460 count, t)) 461 return 0; 462 return 1; 463 } 464 465 static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent) 466 { 467 struct dx_countlimit *c; 468 struct dx_tail *t; 469 int count_offset, limit, count; 470 471 if (!ext4_has_metadata_csum(inode->i_sb)) 472 return; 473 474 c = get_dx_countlimit(inode, dirent, &count_offset); 475 if (!c) { 476 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 477 return; 478 } 479 limit = le16_to_cpu(c->limit); 480 count = le16_to_cpu(c->count); 481 if (count_offset + (limit * sizeof(struct dx_entry)) > 482 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 483 warn_no_space_for_csum(inode); 484 return; 485 } 486 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 487 488 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t); 489 } 490 491 static inline int ext4_handle_dirty_dx_node(handle_t *handle, 492 struct inode *inode, 493 struct buffer_head *bh) 494 { 495 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 496 return ext4_handle_dirty_metadata(handle, inode, bh); 497 } 498 499 /* 500 * p is at least 6 bytes before the end of page 501 */ 502 static inline struct ext4_dir_entry_2 * 503 ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize) 504 { 505 return (struct ext4_dir_entry_2 *)((char *)p + 506 ext4_rec_len_from_disk(p->rec_len, blocksize)); 507 } 508 509 /* 510 * Future: use high four bits of block for coalesce-on-delete flags 511 * Mask them off for now. 512 */ 513 514 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry) 515 { 516 return le32_to_cpu(entry->block) & 0x00ffffff; 517 } 518 519 static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value) 520 { 521 entry->block = cpu_to_le32(value); 522 } 523 524 static inline unsigned dx_get_hash(struct dx_entry *entry) 525 { 526 return le32_to_cpu(entry->hash); 527 } 528 529 static inline void dx_set_hash(struct dx_entry *entry, unsigned value) 530 { 531 entry->hash = cpu_to_le32(value); 532 } 533 534 static inline unsigned dx_get_count(struct dx_entry *entries) 535 { 536 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 537 } 538 539 static inline unsigned dx_get_limit(struct dx_entry *entries) 540 { 541 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 542 } 543 544 static inline void dx_set_count(struct dx_entry *entries, unsigned value) 545 { 546 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 547 } 548 549 static inline void dx_set_limit(struct dx_entry *entries, unsigned value) 550 { 551 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 552 } 553 554 static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize) 555 { 556 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) - 557 EXT4_DIR_REC_LEN(2) - infosize; 558 559 if (ext4_has_metadata_csum(dir->i_sb)) 560 entry_space -= sizeof(struct dx_tail); 561 return entry_space / sizeof(struct dx_entry); 562 } 563 564 static inline unsigned dx_node_limit(struct inode *dir) 565 { 566 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0); 567 568 if (ext4_has_metadata_csum(dir->i_sb)) 569 entry_space -= sizeof(struct dx_tail); 570 return entry_space / sizeof(struct dx_entry); 571 } 572 573 /* 574 * Debug 575 */ 576 #ifdef DX_DEBUG 577 static void dx_show_index(char * label, struct dx_entry *entries) 578 { 579 int i, n = dx_get_count (entries); 580 printk(KERN_DEBUG "%s index ", label); 581 for (i = 0; i < n; i++) { 582 printk("%x->%lu ", i ? dx_get_hash(entries + i) : 583 0, (unsigned long)dx_get_block(entries + i)); 584 } 585 printk("\n"); 586 } 587 588 struct stats 589 { 590 unsigned names; 591 unsigned space; 592 unsigned bcount; 593 }; 594 595 static struct stats dx_show_leaf(struct inode *dir, 596 struct dx_hash_info *hinfo, 597 struct ext4_dir_entry_2 *de, 598 int size, int show_names) 599 { 600 unsigned names = 0, space = 0; 601 char *base = (char *) de; 602 struct dx_hash_info h = *hinfo; 603 604 printk("names: "); 605 while ((char *) de < base + size) 606 { 607 if (de->inode) 608 { 609 if (show_names) 610 { 611 #ifdef CONFIG_EXT4_FS_ENCRYPTION 612 int len; 613 char *name; 614 struct fscrypt_str fname_crypto_str = 615 FSTR_INIT(NULL, 0); 616 int res = 0; 617 618 name = de->name; 619 len = de->name_len; 620 if (ext4_encrypted_inode(dir)) 621 res = fscrypt_get_encryption_info(dir); 622 if (res) { 623 printk(KERN_WARNING "Error setting up" 624 " fname crypto: %d\n", res); 625 } 626 if (!fscrypt_has_encryption_key(dir)) { 627 /* Directory is not encrypted */ 628 ext4fs_dirhash(de->name, 629 de->name_len, &h); 630 printk("%*.s:(U)%x.%u ", len, 631 name, h.hash, 632 (unsigned) ((char *) de 633 - base)); 634 } else { 635 struct fscrypt_str de_name = 636 FSTR_INIT(name, len); 637 638 /* Directory is encrypted */ 639 res = fscrypt_fname_alloc_buffer( 640 dir, len, 641 &fname_crypto_str); 642 if (res < 0) 643 printk(KERN_WARNING "Error " 644 "allocating crypto " 645 "buffer--skipping " 646 "crypto\n"); 647 res = fscrypt_fname_disk_to_usr(dir, 648 0, 0, &de_name, 649 &fname_crypto_str); 650 if (res < 0) { 651 printk(KERN_WARNING "Error " 652 "converting filename " 653 "from disk to usr" 654 "\n"); 655 name = "??"; 656 len = 2; 657 } else { 658 name = fname_crypto_str.name; 659 len = fname_crypto_str.len; 660 } 661 ext4fs_dirhash(de->name, de->name_len, 662 &h); 663 printk("%*.s:(E)%x.%u ", len, name, 664 h.hash, (unsigned) ((char *) de 665 - base)); 666 fscrypt_fname_free_buffer( 667 &fname_crypto_str); 668 } 669 #else 670 int len = de->name_len; 671 char *name = de->name; 672 ext4fs_dirhash(de->name, de->name_len, &h); 673 printk("%*.s:%x.%u ", len, name, h.hash, 674 (unsigned) ((char *) de - base)); 675 #endif 676 } 677 space += EXT4_DIR_REC_LEN(de->name_len); 678 names++; 679 } 680 de = ext4_next_entry(de, size); 681 } 682 printk("(%i)\n", names); 683 return (struct stats) { names, space, 1 }; 684 } 685 686 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 687 struct dx_entry *entries, int levels) 688 { 689 unsigned blocksize = dir->i_sb->s_blocksize; 690 unsigned count = dx_get_count(entries), names = 0, space = 0, i; 691 unsigned bcount = 0; 692 struct buffer_head *bh; 693 printk("%i indexed blocks...\n", count); 694 for (i = 0; i < count; i++, entries++) 695 { 696 ext4_lblk_t block = dx_get_block(entries); 697 ext4_lblk_t hash = i ? dx_get_hash(entries): 0; 698 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 699 struct stats stats; 700 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 701 bh = ext4_bread(NULL,dir, block, 0); 702 if (!bh || IS_ERR(bh)) 703 continue; 704 stats = levels? 705 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 706 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) 707 bh->b_data, blocksize, 0); 708 names += stats.names; 709 space += stats.space; 710 bcount += stats.bcount; 711 brelse(bh); 712 } 713 if (bcount) 714 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n", 715 levels ? "" : " ", names, space/bcount, 716 (space/bcount)*100/blocksize); 717 return (struct stats) { names, space, bcount}; 718 } 719 #endif /* DX_DEBUG */ 720 721 /* 722 * Probe for a directory leaf block to search. 723 * 724 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 725 * error in the directory index, and the caller should fall back to 726 * searching the directory normally. The callers of dx_probe **MUST** 727 * check for this error code, and make sure it never gets reflected 728 * back to userspace. 729 */ 730 static struct dx_frame * 731 dx_probe(struct ext4_filename *fname, struct inode *dir, 732 struct dx_hash_info *hinfo, struct dx_frame *frame_in) 733 { 734 unsigned count, indirect; 735 struct dx_entry *at, *entries, *p, *q, *m; 736 struct dx_root *root; 737 struct dx_frame *frame = frame_in; 738 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR); 739 u32 hash; 740 741 frame->bh = ext4_read_dirblock(dir, 0, INDEX); 742 if (IS_ERR(frame->bh)) 743 return (struct dx_frame *) frame->bh; 744 745 root = (struct dx_root *) frame->bh->b_data; 746 if (root->info.hash_version != DX_HASH_TEA && 747 root->info.hash_version != DX_HASH_HALF_MD4 && 748 root->info.hash_version != DX_HASH_LEGACY) { 749 ext4_warning_inode(dir, "Unrecognised inode hash code %u", 750 root->info.hash_version); 751 goto fail; 752 } 753 if (fname) 754 hinfo = &fname->hinfo; 755 hinfo->hash_version = root->info.hash_version; 756 if (hinfo->hash_version <= DX_HASH_TEA) 757 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 758 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; 759 if (fname && fname_name(fname)) 760 ext4fs_dirhash(fname_name(fname), fname_len(fname), hinfo); 761 hash = hinfo->hash; 762 763 if (root->info.unused_flags & 1) { 764 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x", 765 root->info.unused_flags); 766 goto fail; 767 } 768 769 indirect = root->info.indirect_levels; 770 if (indirect > 1) { 771 ext4_warning_inode(dir, "Unimplemented hash depth: %#06x", 772 root->info.indirect_levels); 773 goto fail; 774 } 775 776 entries = (struct dx_entry *)(((char *)&root->info) + 777 root->info.info_length); 778 779 if (dx_get_limit(entries) != dx_root_limit(dir, 780 root->info.info_length)) { 781 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u", 782 dx_get_limit(entries), 783 dx_root_limit(dir, root->info.info_length)); 784 goto fail; 785 } 786 787 dxtrace(printk("Look up %x", hash)); 788 while (1) { 789 count = dx_get_count(entries); 790 if (!count || count > dx_get_limit(entries)) { 791 ext4_warning_inode(dir, 792 "dx entry: count %u beyond limit %u", 793 count, dx_get_limit(entries)); 794 goto fail; 795 } 796 797 p = entries + 1; 798 q = entries + count - 1; 799 while (p <= q) { 800 m = p + (q - p) / 2; 801 dxtrace(printk(".")); 802 if (dx_get_hash(m) > hash) 803 q = m - 1; 804 else 805 p = m + 1; 806 } 807 808 if (0) { // linear search cross check 809 unsigned n = count - 1; 810 at = entries; 811 while (n--) 812 { 813 dxtrace(printk(",")); 814 if (dx_get_hash(++at) > hash) 815 { 816 at--; 817 break; 818 } 819 } 820 assert (at == p - 1); 821 } 822 823 at = p - 1; 824 dxtrace(printk(" %x->%u\n", at == entries ? 0 : dx_get_hash(at), 825 dx_get_block(at))); 826 frame->entries = entries; 827 frame->at = at; 828 if (!indirect--) 829 return frame; 830 frame++; 831 frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX); 832 if (IS_ERR(frame->bh)) { 833 ret_err = (struct dx_frame *) frame->bh; 834 frame->bh = NULL; 835 goto fail; 836 } 837 entries = ((struct dx_node *) frame->bh->b_data)->entries; 838 839 if (dx_get_limit(entries) != dx_node_limit(dir)) { 840 ext4_warning_inode(dir, 841 "dx entry: limit %u != node limit %u", 842 dx_get_limit(entries), dx_node_limit(dir)); 843 goto fail; 844 } 845 } 846 fail: 847 while (frame >= frame_in) { 848 brelse(frame->bh); 849 frame--; 850 } 851 852 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR)) 853 ext4_warning_inode(dir, 854 "Corrupt directory, running e2fsck is recommended"); 855 return ret_err; 856 } 857 858 static void dx_release(struct dx_frame *frames) 859 { 860 if (frames[0].bh == NULL) 861 return; 862 863 if (((struct dx_root *)frames[0].bh->b_data)->info.indirect_levels) 864 brelse(frames[1].bh); 865 brelse(frames[0].bh); 866 } 867 868 /* 869 * This function increments the frame pointer to search the next leaf 870 * block, and reads in the necessary intervening nodes if the search 871 * should be necessary. Whether or not the search is necessary is 872 * controlled by the hash parameter. If the hash value is even, then 873 * the search is only continued if the next block starts with that 874 * hash value. This is used if we are searching for a specific file. 875 * 876 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 877 * 878 * This function returns 1 if the caller should continue to search, 879 * or 0 if it should not. If there is an error reading one of the 880 * index blocks, it will a negative error code. 881 * 882 * If start_hash is non-null, it will be filled in with the starting 883 * hash of the next page. 884 */ 885 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 886 struct dx_frame *frame, 887 struct dx_frame *frames, 888 __u32 *start_hash) 889 { 890 struct dx_frame *p; 891 struct buffer_head *bh; 892 int num_frames = 0; 893 __u32 bhash; 894 895 p = frame; 896 /* 897 * Find the next leaf page by incrementing the frame pointer. 898 * If we run out of entries in the interior node, loop around and 899 * increment pointer in the parent node. When we break out of 900 * this loop, num_frames indicates the number of interior 901 * nodes need to be read. 902 */ 903 while (1) { 904 if (++(p->at) < p->entries + dx_get_count(p->entries)) 905 break; 906 if (p == frames) 907 return 0; 908 num_frames++; 909 p--; 910 } 911 912 /* 913 * If the hash is 1, then continue only if the next page has a 914 * continuation hash of any value. This is used for readdir 915 * handling. Otherwise, check to see if the hash matches the 916 * desired contiuation hash. If it doesn't, return since 917 * there's no point to read in the successive index pages. 918 */ 919 bhash = dx_get_hash(p->at); 920 if (start_hash) 921 *start_hash = bhash; 922 if ((hash & 1) == 0) { 923 if ((bhash & ~1) != hash) 924 return 0; 925 } 926 /* 927 * If the hash is HASH_NB_ALWAYS, we always go to the next 928 * block so no check is necessary 929 */ 930 while (num_frames--) { 931 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX); 932 if (IS_ERR(bh)) 933 return PTR_ERR(bh); 934 p++; 935 brelse(p->bh); 936 p->bh = bh; 937 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 938 } 939 return 1; 940 } 941 942 943 /* 944 * This function fills a red-black tree with information from a 945 * directory block. It returns the number directory entries loaded 946 * into the tree. If there is an error it is returned in err. 947 */ 948 static int htree_dirblock_to_tree(struct file *dir_file, 949 struct inode *dir, ext4_lblk_t block, 950 struct dx_hash_info *hinfo, 951 __u32 start_hash, __u32 start_minor_hash) 952 { 953 struct buffer_head *bh; 954 struct ext4_dir_entry_2 *de, *top; 955 int err = 0, count = 0; 956 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str; 957 958 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", 959 (unsigned long)block)); 960 bh = ext4_read_dirblock(dir, block, DIRENT); 961 if (IS_ERR(bh)) 962 return PTR_ERR(bh); 963 964 de = (struct ext4_dir_entry_2 *) bh->b_data; 965 top = (struct ext4_dir_entry_2 *) ((char *) de + 966 dir->i_sb->s_blocksize - 967 EXT4_DIR_REC_LEN(0)); 968 #ifdef CONFIG_EXT4_FS_ENCRYPTION 969 /* Check if the directory is encrypted */ 970 if (ext4_encrypted_inode(dir)) { 971 err = fscrypt_get_encryption_info(dir); 972 if (err < 0) { 973 brelse(bh); 974 return err; 975 } 976 err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN, 977 &fname_crypto_str); 978 if (err < 0) { 979 brelse(bh); 980 return err; 981 } 982 } 983 #endif 984 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { 985 if (ext4_check_dir_entry(dir, NULL, de, bh, 986 bh->b_data, bh->b_size, 987 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb)) 988 + ((char *)de - bh->b_data))) { 989 /* silently ignore the rest of the block */ 990 break; 991 } 992 ext4fs_dirhash(de->name, de->name_len, hinfo); 993 if ((hinfo->hash < start_hash) || 994 ((hinfo->hash == start_hash) && 995 (hinfo->minor_hash < start_minor_hash))) 996 continue; 997 if (de->inode == 0) 998 continue; 999 if (!ext4_encrypted_inode(dir)) { 1000 tmp_str.name = de->name; 1001 tmp_str.len = de->name_len; 1002 err = ext4_htree_store_dirent(dir_file, 1003 hinfo->hash, hinfo->minor_hash, de, 1004 &tmp_str); 1005 } else { 1006 int save_len = fname_crypto_str.len; 1007 struct fscrypt_str de_name = FSTR_INIT(de->name, 1008 de->name_len); 1009 1010 /* Directory is encrypted */ 1011 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash, 1012 hinfo->minor_hash, &de_name, 1013 &fname_crypto_str); 1014 if (err < 0) { 1015 count = err; 1016 goto errout; 1017 } 1018 err = ext4_htree_store_dirent(dir_file, 1019 hinfo->hash, hinfo->minor_hash, de, 1020 &fname_crypto_str); 1021 fname_crypto_str.len = save_len; 1022 } 1023 if (err != 0) { 1024 count = err; 1025 goto errout; 1026 } 1027 count++; 1028 } 1029 errout: 1030 brelse(bh); 1031 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1032 fscrypt_fname_free_buffer(&fname_crypto_str); 1033 #endif 1034 return count; 1035 } 1036 1037 1038 /* 1039 * This function fills a red-black tree with information from a 1040 * directory. We start scanning the directory in hash order, starting 1041 * at start_hash and start_minor_hash. 1042 * 1043 * This function returns the number of entries inserted into the tree, 1044 * or a negative error code. 1045 */ 1046 int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, 1047 __u32 start_minor_hash, __u32 *next_hash) 1048 { 1049 struct dx_hash_info hinfo; 1050 struct ext4_dir_entry_2 *de; 1051 struct dx_frame frames[2], *frame; 1052 struct inode *dir; 1053 ext4_lblk_t block; 1054 int count = 0; 1055 int ret, err; 1056 __u32 hashval; 1057 struct fscrypt_str tmp_str; 1058 1059 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n", 1060 start_hash, start_minor_hash)); 1061 dir = file_inode(dir_file); 1062 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) { 1063 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1064 if (hinfo.hash_version <= DX_HASH_TEA) 1065 hinfo.hash_version += 1066 EXT4_SB(dir->i_sb)->s_hash_unsigned; 1067 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1068 if (ext4_has_inline_data(dir)) { 1069 int has_inline_data = 1; 1070 count = htree_inlinedir_to_tree(dir_file, dir, 0, 1071 &hinfo, start_hash, 1072 start_minor_hash, 1073 &has_inline_data); 1074 if (has_inline_data) { 1075 *next_hash = ~0; 1076 return count; 1077 } 1078 } 1079 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 1080 start_hash, start_minor_hash); 1081 *next_hash = ~0; 1082 return count; 1083 } 1084 hinfo.hash = start_hash; 1085 hinfo.minor_hash = 0; 1086 frame = dx_probe(NULL, dir, &hinfo, frames); 1087 if (IS_ERR(frame)) 1088 return PTR_ERR(frame); 1089 1090 /* Add '.' and '..' from the htree header */ 1091 if (!start_hash && !start_minor_hash) { 1092 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1093 tmp_str.name = de->name; 1094 tmp_str.len = de->name_len; 1095 err = ext4_htree_store_dirent(dir_file, 0, 0, 1096 de, &tmp_str); 1097 if (err != 0) 1098 goto errout; 1099 count++; 1100 } 1101 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 1102 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1103 de = ext4_next_entry(de, dir->i_sb->s_blocksize); 1104 tmp_str.name = de->name; 1105 tmp_str.len = de->name_len; 1106 err = ext4_htree_store_dirent(dir_file, 2, 0, 1107 de, &tmp_str); 1108 if (err != 0) 1109 goto errout; 1110 count++; 1111 } 1112 1113 while (1) { 1114 if (fatal_signal_pending(current)) { 1115 err = -ERESTARTSYS; 1116 goto errout; 1117 } 1118 cond_resched(); 1119 block = dx_get_block(frame->at); 1120 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 1121 start_hash, start_minor_hash); 1122 if (ret < 0) { 1123 err = ret; 1124 goto errout; 1125 } 1126 count += ret; 1127 hashval = ~0; 1128 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS, 1129 frame, frames, &hashval); 1130 *next_hash = hashval; 1131 if (ret < 0) { 1132 err = ret; 1133 goto errout; 1134 } 1135 /* 1136 * Stop if: (a) there are no more entries, or 1137 * (b) we have inserted at least one entry and the 1138 * next hash value is not a continuation 1139 */ 1140 if ((ret == 0) || 1141 (count && ((hashval & 1) == 0))) 1142 break; 1143 } 1144 dx_release(frames); 1145 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, " 1146 "next hash: %x\n", count, *next_hash)); 1147 return count; 1148 errout: 1149 dx_release(frames); 1150 return (err); 1151 } 1152 1153 static inline int search_dirblock(struct buffer_head *bh, 1154 struct inode *dir, 1155 struct ext4_filename *fname, 1156 const struct qstr *d_name, 1157 unsigned int offset, 1158 struct ext4_dir_entry_2 **res_dir) 1159 { 1160 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir, 1161 fname, d_name, offset, res_dir); 1162 } 1163 1164 /* 1165 * Directory block splitting, compacting 1166 */ 1167 1168 /* 1169 * Create map of hash values, offsets, and sizes, stored at end of block. 1170 * Returns number of entries mapped. 1171 */ 1172 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 1173 unsigned blocksize, struct dx_hash_info *hinfo, 1174 struct dx_map_entry *map_tail) 1175 { 1176 int count = 0; 1177 char *base = (char *) de; 1178 struct dx_hash_info h = *hinfo; 1179 1180 while ((char *) de < base + blocksize) { 1181 if (de->name_len && de->inode) { 1182 ext4fs_dirhash(de->name, de->name_len, &h); 1183 map_tail--; 1184 map_tail->hash = h.hash; 1185 map_tail->offs = ((char *) de - base)>>2; 1186 map_tail->size = le16_to_cpu(de->rec_len); 1187 count++; 1188 cond_resched(); 1189 } 1190 /* XXX: do we need to check rec_len == 0 case? -Chris */ 1191 de = ext4_next_entry(de, blocksize); 1192 } 1193 return count; 1194 } 1195 1196 /* Sort map by hash value */ 1197 static void dx_sort_map (struct dx_map_entry *map, unsigned count) 1198 { 1199 struct dx_map_entry *p, *q, *top = map + count - 1; 1200 int more; 1201 /* Combsort until bubble sort doesn't suck */ 1202 while (count > 2) { 1203 count = count*10/13; 1204 if (count - 9 < 2) /* 9, 10 -> 11 */ 1205 count = 11; 1206 for (p = top, q = p - count; q >= map; p--, q--) 1207 if (p->hash < q->hash) 1208 swap(*p, *q); 1209 } 1210 /* Garden variety bubble sort */ 1211 do { 1212 more = 0; 1213 q = top; 1214 while (q-- > map) { 1215 if (q[1].hash >= q[0].hash) 1216 continue; 1217 swap(*(q+1), *q); 1218 more = 1; 1219 } 1220 } while(more); 1221 } 1222 1223 static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) 1224 { 1225 struct dx_entry *entries = frame->entries; 1226 struct dx_entry *old = frame->at, *new = old + 1; 1227 int count = dx_get_count(entries); 1228 1229 assert(count < dx_get_limit(entries)); 1230 assert(old < entries + count); 1231 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 1232 dx_set_hash(new, hash); 1233 dx_set_block(new, block); 1234 dx_set_count(entries, count + 1); 1235 } 1236 1237 /* 1238 * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure. 1239 * 1240 * `len <= EXT4_NAME_LEN' is guaranteed by caller. 1241 * `de != NULL' is guaranteed by caller. 1242 */ 1243 static inline int ext4_match(struct ext4_filename *fname, 1244 struct ext4_dir_entry_2 *de) 1245 { 1246 const void *name = fname_name(fname); 1247 u32 len = fname_len(fname); 1248 1249 if (!de->inode) 1250 return 0; 1251 1252 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1253 if (unlikely(!name)) { 1254 if (fname->usr_fname->name[0] == '_') { 1255 int ret; 1256 if (de->name_len < 16) 1257 return 0; 1258 ret = memcmp(de->name + de->name_len - 16, 1259 fname->crypto_buf.name + 8, 16); 1260 return (ret == 0) ? 1 : 0; 1261 } 1262 name = fname->crypto_buf.name; 1263 len = fname->crypto_buf.len; 1264 } 1265 #endif 1266 if (de->name_len != len) 1267 return 0; 1268 return (memcmp(de->name, name, len) == 0) ? 1 : 0; 1269 } 1270 1271 /* 1272 * Returns 0 if not found, -1 on failure, and 1 on success 1273 */ 1274 int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, 1275 struct inode *dir, struct ext4_filename *fname, 1276 const struct qstr *d_name, 1277 unsigned int offset, struct ext4_dir_entry_2 **res_dir) 1278 { 1279 struct ext4_dir_entry_2 * de; 1280 char * dlimit; 1281 int de_len; 1282 int res; 1283 1284 de = (struct ext4_dir_entry_2 *)search_buf; 1285 dlimit = search_buf + buf_size; 1286 while ((char *) de < dlimit) { 1287 /* this code is executed quadratically often */ 1288 /* do minimal checking `by hand' */ 1289 if ((char *) de + de->name_len <= dlimit) { 1290 res = ext4_match(fname, de); 1291 if (res < 0) { 1292 res = -1; 1293 goto return_result; 1294 } 1295 if (res > 0) { 1296 /* found a match - just to be sure, do 1297 * a full check */ 1298 if (ext4_check_dir_entry(dir, NULL, de, bh, 1299 bh->b_data, 1300 bh->b_size, offset)) { 1301 res = -1; 1302 goto return_result; 1303 } 1304 *res_dir = de; 1305 res = 1; 1306 goto return_result; 1307 } 1308 1309 } 1310 /* prevent looping on a bad block */ 1311 de_len = ext4_rec_len_from_disk(de->rec_len, 1312 dir->i_sb->s_blocksize); 1313 if (de_len <= 0) { 1314 res = -1; 1315 goto return_result; 1316 } 1317 offset += de_len; 1318 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); 1319 } 1320 1321 res = 0; 1322 return_result: 1323 return res; 1324 } 1325 1326 static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block, 1327 struct ext4_dir_entry *de) 1328 { 1329 struct super_block *sb = dir->i_sb; 1330 1331 if (!is_dx(dir)) 1332 return 0; 1333 if (block == 0) 1334 return 1; 1335 if (de->inode == 0 && 1336 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) == 1337 sb->s_blocksize) 1338 return 1; 1339 return 0; 1340 } 1341 1342 /* 1343 * ext4_find_entry() 1344 * 1345 * finds an entry in the specified directory with the wanted name. It 1346 * returns the cache buffer in which the entry was found, and the entry 1347 * itself (as a parameter - res_dir). It does NOT read the inode of the 1348 * entry - you'll have to do that yourself if you want to. 1349 * 1350 * The returned buffer_head has ->b_count elevated. The caller is expected 1351 * to brelse() it when appropriate. 1352 */ 1353 static struct buffer_head * ext4_find_entry (struct inode *dir, 1354 const struct qstr *d_name, 1355 struct ext4_dir_entry_2 **res_dir, 1356 int *inlined) 1357 { 1358 struct super_block *sb; 1359 struct buffer_head *bh_use[NAMEI_RA_SIZE]; 1360 struct buffer_head *bh, *ret = NULL; 1361 ext4_lblk_t start, block, b; 1362 const u8 *name = d_name->name; 1363 int ra_max = 0; /* Number of bh's in the readahead 1364 buffer, bh_use[] */ 1365 int ra_ptr = 0; /* Current index into readahead 1366 buffer */ 1367 int num = 0; 1368 ext4_lblk_t nblocks; 1369 int i, namelen, retval; 1370 struct ext4_filename fname; 1371 1372 *res_dir = NULL; 1373 sb = dir->i_sb; 1374 namelen = d_name->len; 1375 if (namelen > EXT4_NAME_LEN) 1376 return NULL; 1377 1378 retval = ext4_fname_setup_filename(dir, d_name, 1, &fname); 1379 if (retval) 1380 return ERR_PTR(retval); 1381 1382 if (ext4_has_inline_data(dir)) { 1383 int has_inline_data = 1; 1384 ret = ext4_find_inline_entry(dir, &fname, d_name, res_dir, 1385 &has_inline_data); 1386 if (has_inline_data) { 1387 if (inlined) 1388 *inlined = 1; 1389 goto cleanup_and_exit; 1390 } 1391 } 1392 1393 if ((namelen <= 2) && (name[0] == '.') && 1394 (name[1] == '.' || name[1] == '\0')) { 1395 /* 1396 * "." or ".." will only be in the first block 1397 * NFS may look up ".."; "." should be handled by the VFS 1398 */ 1399 block = start = 0; 1400 nblocks = 1; 1401 goto restart; 1402 } 1403 if (is_dx(dir)) { 1404 ret = ext4_dx_find_entry(dir, &fname, res_dir); 1405 /* 1406 * On success, or if the error was file not found, 1407 * return. Otherwise, fall back to doing a search the 1408 * old fashioned way. 1409 */ 1410 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) 1411 goto cleanup_and_exit; 1412 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " 1413 "falling back\n")); 1414 } 1415 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1416 start = EXT4_I(dir)->i_dir_start_lookup; 1417 if (start >= nblocks) 1418 start = 0; 1419 block = start; 1420 restart: 1421 do { 1422 /* 1423 * We deal with the read-ahead logic here. 1424 */ 1425 if (ra_ptr >= ra_max) { 1426 /* Refill the readahead buffer */ 1427 ra_ptr = 0; 1428 b = block; 1429 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) { 1430 /* 1431 * Terminate if we reach the end of the 1432 * directory and must wrap, or if our 1433 * search has finished at this block. 1434 */ 1435 if (b >= nblocks || (num && block == start)) { 1436 bh_use[ra_max] = NULL; 1437 break; 1438 } 1439 num++; 1440 bh = ext4_getblk(NULL, dir, b++, 0); 1441 if (IS_ERR(bh)) { 1442 if (ra_max == 0) { 1443 ret = bh; 1444 goto cleanup_and_exit; 1445 } 1446 break; 1447 } 1448 bh_use[ra_max] = bh; 1449 if (bh) 1450 ll_rw_block(REQ_OP_READ, 1451 REQ_META | REQ_PRIO, 1452 1, &bh); 1453 } 1454 } 1455 if ((bh = bh_use[ra_ptr++]) == NULL) 1456 goto next; 1457 wait_on_buffer(bh); 1458 if (!buffer_uptodate(bh)) { 1459 /* read error, skip block & hope for the best */ 1460 EXT4_ERROR_INODE(dir, "reading directory lblock %lu", 1461 (unsigned long) block); 1462 brelse(bh); 1463 goto next; 1464 } 1465 if (!buffer_verified(bh) && 1466 !is_dx_internal_node(dir, block, 1467 (struct ext4_dir_entry *)bh->b_data) && 1468 !ext4_dirent_csum_verify(dir, 1469 (struct ext4_dir_entry *)bh->b_data)) { 1470 EXT4_ERROR_INODE(dir, "checksumming directory " 1471 "block %lu", (unsigned long)block); 1472 brelse(bh); 1473 goto next; 1474 } 1475 set_buffer_verified(bh); 1476 i = search_dirblock(bh, dir, &fname, d_name, 1477 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); 1478 if (i == 1) { 1479 EXT4_I(dir)->i_dir_start_lookup = block; 1480 ret = bh; 1481 goto cleanup_and_exit; 1482 } else { 1483 brelse(bh); 1484 if (i < 0) 1485 goto cleanup_and_exit; 1486 } 1487 next: 1488 if (++block >= nblocks) 1489 block = 0; 1490 } while (block != start); 1491 1492 /* 1493 * If the directory has grown while we were searching, then 1494 * search the last part of the directory before giving up. 1495 */ 1496 block = nblocks; 1497 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1498 if (block < nblocks) { 1499 start = 0; 1500 goto restart; 1501 } 1502 1503 cleanup_and_exit: 1504 /* Clean up the read-ahead blocks */ 1505 for (; ra_ptr < ra_max; ra_ptr++) 1506 brelse(bh_use[ra_ptr]); 1507 ext4_fname_free_filename(&fname); 1508 return ret; 1509 } 1510 1511 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 1512 struct ext4_filename *fname, 1513 struct ext4_dir_entry_2 **res_dir) 1514 { 1515 struct super_block * sb = dir->i_sb; 1516 struct dx_frame frames[2], *frame; 1517 const struct qstr *d_name = fname->usr_fname; 1518 struct buffer_head *bh; 1519 ext4_lblk_t block; 1520 int retval; 1521 1522 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1523 *res_dir = NULL; 1524 #endif 1525 frame = dx_probe(fname, dir, NULL, frames); 1526 if (IS_ERR(frame)) 1527 return (struct buffer_head *) frame; 1528 do { 1529 block = dx_get_block(frame->at); 1530 bh = ext4_read_dirblock(dir, block, DIRENT); 1531 if (IS_ERR(bh)) 1532 goto errout; 1533 1534 retval = search_dirblock(bh, dir, fname, d_name, 1535 block << EXT4_BLOCK_SIZE_BITS(sb), 1536 res_dir); 1537 if (retval == 1) 1538 goto success; 1539 brelse(bh); 1540 if (retval == -1) { 1541 bh = ERR_PTR(ERR_BAD_DX_DIR); 1542 goto errout; 1543 } 1544 1545 /* Check to see if we should continue to search */ 1546 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame, 1547 frames, NULL); 1548 if (retval < 0) { 1549 ext4_warning_inode(dir, 1550 "error %d reading directory index block", 1551 retval); 1552 bh = ERR_PTR(retval); 1553 goto errout; 1554 } 1555 } while (retval == 1); 1556 1557 bh = NULL; 1558 errout: 1559 dxtrace(printk(KERN_DEBUG "%s not found\n", d_name->name)); 1560 success: 1561 dx_release(frames); 1562 return bh; 1563 } 1564 1565 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 1566 { 1567 struct inode *inode; 1568 struct ext4_dir_entry_2 *de; 1569 struct buffer_head *bh; 1570 1571 if (ext4_encrypted_inode(dir)) { 1572 int res = fscrypt_get_encryption_info(dir); 1573 1574 /* 1575 * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is 1576 * created while the directory was encrypted and we 1577 * have access to the key. 1578 */ 1579 if (fscrypt_has_encryption_key(dir)) 1580 fscrypt_set_encrypted_dentry(dentry); 1581 fscrypt_set_d_op(dentry); 1582 if (res && res != -ENOKEY) 1583 return ERR_PTR(res); 1584 } 1585 1586 if (dentry->d_name.len > EXT4_NAME_LEN) 1587 return ERR_PTR(-ENAMETOOLONG); 1588 1589 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 1590 if (IS_ERR(bh)) 1591 return (struct dentry *) bh; 1592 inode = NULL; 1593 if (bh) { 1594 __u32 ino = le32_to_cpu(de->inode); 1595 brelse(bh); 1596 if (!ext4_valid_inum(dir->i_sb, ino)) { 1597 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); 1598 return ERR_PTR(-EFSCORRUPTED); 1599 } 1600 if (unlikely(ino == dir->i_ino)) { 1601 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir", 1602 dentry); 1603 return ERR_PTR(-EFSCORRUPTED); 1604 } 1605 inode = ext4_iget_normal(dir->i_sb, ino); 1606 if (inode == ERR_PTR(-ESTALE)) { 1607 EXT4_ERROR_INODE(dir, 1608 "deleted inode referenced: %u", 1609 ino); 1610 return ERR_PTR(-EFSCORRUPTED); 1611 } 1612 if (!IS_ERR(inode) && ext4_encrypted_inode(dir) && 1613 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && 1614 !fscrypt_has_permitted_context(dir, inode)) { 1615 int nokey = ext4_encrypted_inode(inode) && 1616 !fscrypt_has_encryption_key(inode); 1617 iput(inode); 1618 if (nokey) 1619 return ERR_PTR(-ENOKEY); 1620 ext4_warning(inode->i_sb, 1621 "Inconsistent encryption contexts: %lu/%lu", 1622 (unsigned long) dir->i_ino, 1623 (unsigned long) inode->i_ino); 1624 return ERR_PTR(-EPERM); 1625 } 1626 } 1627 return d_splice_alias(inode, dentry); 1628 } 1629 1630 1631 struct dentry *ext4_get_parent(struct dentry *child) 1632 { 1633 __u32 ino; 1634 static const struct qstr dotdot = QSTR_INIT("..", 2); 1635 struct ext4_dir_entry_2 * de; 1636 struct buffer_head *bh; 1637 1638 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL); 1639 if (IS_ERR(bh)) 1640 return (struct dentry *) bh; 1641 if (!bh) 1642 return ERR_PTR(-ENOENT); 1643 ino = le32_to_cpu(de->inode); 1644 brelse(bh); 1645 1646 if (!ext4_valid_inum(child->d_sb, ino)) { 1647 EXT4_ERROR_INODE(d_inode(child), 1648 "bad parent inode number: %u", ino); 1649 return ERR_PTR(-EFSCORRUPTED); 1650 } 1651 1652 return d_obtain_alias(ext4_iget_normal(child->d_sb, ino)); 1653 } 1654 1655 /* 1656 * Move count entries from end of map between two memory locations. 1657 * Returns pointer to last entry moved. 1658 */ 1659 static struct ext4_dir_entry_2 * 1660 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, 1661 unsigned blocksize) 1662 { 1663 unsigned rec_len = 0; 1664 1665 while (count--) { 1666 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) 1667 (from + (map->offs<<2)); 1668 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1669 memcpy (to, de, rec_len); 1670 ((struct ext4_dir_entry_2 *) to)->rec_len = 1671 ext4_rec_len_to_disk(rec_len, blocksize); 1672 de->inode = 0; 1673 map++; 1674 to += rec_len; 1675 } 1676 return (struct ext4_dir_entry_2 *) (to - rec_len); 1677 } 1678 1679 /* 1680 * Compact each dir entry in the range to the minimal rec_len. 1681 * Returns pointer to last entry in range. 1682 */ 1683 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) 1684 { 1685 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; 1686 unsigned rec_len = 0; 1687 1688 prev = to = de; 1689 while ((char*)de < base + blocksize) { 1690 next = ext4_next_entry(de, blocksize); 1691 if (de->inode && de->name_len) { 1692 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1693 if (de > to) 1694 memmove(to, de, rec_len); 1695 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); 1696 prev = to; 1697 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); 1698 } 1699 de = next; 1700 } 1701 return prev; 1702 } 1703 1704 /* 1705 * Split a full leaf block to make room for a new dir entry. 1706 * Allocate a new block, and move entries so that they are approx. equally full. 1707 * Returns pointer to de in block into which the new entry will be inserted. 1708 */ 1709 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1710 struct buffer_head **bh,struct dx_frame *frame, 1711 struct dx_hash_info *hinfo) 1712 { 1713 unsigned blocksize = dir->i_sb->s_blocksize; 1714 unsigned count, continued; 1715 struct buffer_head *bh2; 1716 ext4_lblk_t newblock; 1717 u32 hash2; 1718 struct dx_map_entry *map; 1719 char *data1 = (*bh)->b_data, *data2; 1720 unsigned split, move, size; 1721 struct ext4_dir_entry_2 *de = NULL, *de2; 1722 struct ext4_dir_entry_tail *t; 1723 int csum_size = 0; 1724 int err = 0, i; 1725 1726 if (ext4_has_metadata_csum(dir->i_sb)) 1727 csum_size = sizeof(struct ext4_dir_entry_tail); 1728 1729 bh2 = ext4_append(handle, dir, &newblock); 1730 if (IS_ERR(bh2)) { 1731 brelse(*bh); 1732 *bh = NULL; 1733 return (struct ext4_dir_entry_2 *) bh2; 1734 } 1735 1736 BUFFER_TRACE(*bh, "get_write_access"); 1737 err = ext4_journal_get_write_access(handle, *bh); 1738 if (err) 1739 goto journal_error; 1740 1741 BUFFER_TRACE(frame->bh, "get_write_access"); 1742 err = ext4_journal_get_write_access(handle, frame->bh); 1743 if (err) 1744 goto journal_error; 1745 1746 data2 = bh2->b_data; 1747 1748 /* create map in the end of data2 block */ 1749 map = (struct dx_map_entry *) (data2 + blocksize); 1750 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1, 1751 blocksize, hinfo, map); 1752 map -= count; 1753 dx_sort_map(map, count); 1754 /* Split the existing block in the middle, size-wise */ 1755 size = 0; 1756 move = 0; 1757 for (i = count-1; i >= 0; i--) { 1758 /* is more than half of this entry in 2nd half of the block? */ 1759 if (size + map[i].size/2 > blocksize/2) 1760 break; 1761 size += map[i].size; 1762 move++; 1763 } 1764 /* map index at which we will split */ 1765 split = count - move; 1766 hash2 = map[split].hash; 1767 continued = hash2 == map[split - 1].hash; 1768 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", 1769 (unsigned long)dx_get_block(frame->at), 1770 hash2, split, count-split)); 1771 1772 /* Fancy dance to stay within two buffers */ 1773 de2 = dx_move_dirents(data1, data2, map + split, count - split, 1774 blocksize); 1775 de = dx_pack_dirents(data1, blocksize); 1776 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1777 (char *) de, 1778 blocksize); 1779 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - 1780 (char *) de2, 1781 blocksize); 1782 if (csum_size) { 1783 t = EXT4_DIRENT_TAIL(data2, blocksize); 1784 initialize_dirent_tail(t, blocksize); 1785 1786 t = EXT4_DIRENT_TAIL(data1, blocksize); 1787 initialize_dirent_tail(t, blocksize); 1788 } 1789 1790 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1, 1791 blocksize, 1)); 1792 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2, 1793 blocksize, 1)); 1794 1795 /* Which block gets the new entry? */ 1796 if (hinfo->hash >= hash2) { 1797 swap(*bh, bh2); 1798 de = de2; 1799 } 1800 dx_insert_block(frame, hash2 + continued, newblock); 1801 err = ext4_handle_dirty_dirent_node(handle, dir, bh2); 1802 if (err) 1803 goto journal_error; 1804 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1805 if (err) 1806 goto journal_error; 1807 brelse(bh2); 1808 dxtrace(dx_show_index("frame", frame->entries)); 1809 return de; 1810 1811 journal_error: 1812 brelse(*bh); 1813 brelse(bh2); 1814 *bh = NULL; 1815 ext4_std_error(dir->i_sb, err); 1816 return ERR_PTR(err); 1817 } 1818 1819 int ext4_find_dest_de(struct inode *dir, struct inode *inode, 1820 struct buffer_head *bh, 1821 void *buf, int buf_size, 1822 struct ext4_filename *fname, 1823 struct ext4_dir_entry_2 **dest_de) 1824 { 1825 struct ext4_dir_entry_2 *de; 1826 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname)); 1827 int nlen, rlen; 1828 unsigned int offset = 0; 1829 char *top; 1830 int res; 1831 1832 de = (struct ext4_dir_entry_2 *)buf; 1833 top = buf + buf_size - reclen; 1834 while ((char *) de <= top) { 1835 if (ext4_check_dir_entry(dir, NULL, de, bh, 1836 buf, buf_size, offset)) { 1837 res = -EFSCORRUPTED; 1838 goto return_result; 1839 } 1840 /* Provide crypto context and crypto buffer to ext4 match */ 1841 res = ext4_match(fname, de); 1842 if (res < 0) 1843 goto return_result; 1844 if (res > 0) { 1845 res = -EEXIST; 1846 goto return_result; 1847 } 1848 nlen = EXT4_DIR_REC_LEN(de->name_len); 1849 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1850 if ((de->inode ? rlen - nlen : rlen) >= reclen) 1851 break; 1852 de = (struct ext4_dir_entry_2 *)((char *)de + rlen); 1853 offset += rlen; 1854 } 1855 1856 if ((char *) de > top) 1857 res = -ENOSPC; 1858 else { 1859 *dest_de = de; 1860 res = 0; 1861 } 1862 return_result: 1863 return res; 1864 } 1865 1866 int ext4_insert_dentry(struct inode *dir, 1867 struct inode *inode, 1868 struct ext4_dir_entry_2 *de, 1869 int buf_size, 1870 struct ext4_filename *fname) 1871 { 1872 1873 int nlen, rlen; 1874 1875 nlen = EXT4_DIR_REC_LEN(de->name_len); 1876 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1877 if (de->inode) { 1878 struct ext4_dir_entry_2 *de1 = 1879 (struct ext4_dir_entry_2 *)((char *)de + nlen); 1880 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); 1881 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); 1882 de = de1; 1883 } 1884 de->file_type = EXT4_FT_UNKNOWN; 1885 de->inode = cpu_to_le32(inode->i_ino); 1886 ext4_set_de_type(inode->i_sb, de, inode->i_mode); 1887 de->name_len = fname_len(fname); 1888 memcpy(de->name, fname_name(fname), fname_len(fname)); 1889 return 0; 1890 } 1891 1892 /* 1893 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1894 * it points to a directory entry which is guaranteed to be large 1895 * enough for new directory entry. If de is NULL, then 1896 * add_dirent_to_buf will attempt search the directory block for 1897 * space. It will return -ENOSPC if no space is available, and -EIO 1898 * and -EEXIST if directory entry already exists. 1899 */ 1900 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname, 1901 struct inode *dir, 1902 struct inode *inode, struct ext4_dir_entry_2 *de, 1903 struct buffer_head *bh) 1904 { 1905 unsigned int blocksize = dir->i_sb->s_blocksize; 1906 int csum_size = 0; 1907 int err; 1908 1909 if (ext4_has_metadata_csum(inode->i_sb)) 1910 csum_size = sizeof(struct ext4_dir_entry_tail); 1911 1912 if (!de) { 1913 err = ext4_find_dest_de(dir, inode, bh, bh->b_data, 1914 blocksize - csum_size, fname, &de); 1915 if (err) 1916 return err; 1917 } 1918 BUFFER_TRACE(bh, "get_write_access"); 1919 err = ext4_journal_get_write_access(handle, bh); 1920 if (err) { 1921 ext4_std_error(dir->i_sb, err); 1922 return err; 1923 } 1924 1925 /* By now the buffer is marked for journaling. Due to crypto operations, 1926 * the following function call may fail */ 1927 err = ext4_insert_dentry(dir, inode, de, blocksize, fname); 1928 if (err < 0) 1929 return err; 1930 1931 /* 1932 * XXX shouldn't update any times until successful 1933 * completion of syscall, but too many callers depend 1934 * on this. 1935 * 1936 * XXX similarly, too many callers depend on 1937 * ext4_new_inode() setting the times, but error 1938 * recovery deletes the inode, so the worst that can 1939 * happen is that the times are slightly out of date 1940 * and/or different from the directory change time. 1941 */ 1942 dir->i_mtime = dir->i_ctime = ext4_current_time(dir); 1943 ext4_update_dx_flag(dir); 1944 dir->i_version++; 1945 ext4_mark_inode_dirty(handle, dir); 1946 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 1947 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 1948 if (err) 1949 ext4_std_error(dir->i_sb, err); 1950 return 0; 1951 } 1952 1953 /* 1954 * This converts a one block unindexed directory to a 3 block indexed 1955 * directory, and adds the dentry to the indexed directory. 1956 */ 1957 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, 1958 struct inode *dir, 1959 struct inode *inode, struct buffer_head *bh) 1960 { 1961 struct buffer_head *bh2; 1962 struct dx_root *root; 1963 struct dx_frame frames[2], *frame; 1964 struct dx_entry *entries; 1965 struct ext4_dir_entry_2 *de, *de2; 1966 struct ext4_dir_entry_tail *t; 1967 char *data1, *top; 1968 unsigned len; 1969 int retval; 1970 unsigned blocksize; 1971 ext4_lblk_t block; 1972 struct fake_dirent *fde; 1973 int csum_size = 0; 1974 1975 if (ext4_has_metadata_csum(inode->i_sb)) 1976 csum_size = sizeof(struct ext4_dir_entry_tail); 1977 1978 blocksize = dir->i_sb->s_blocksize; 1979 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); 1980 BUFFER_TRACE(bh, "get_write_access"); 1981 retval = ext4_journal_get_write_access(handle, bh); 1982 if (retval) { 1983 ext4_std_error(dir->i_sb, retval); 1984 brelse(bh); 1985 return retval; 1986 } 1987 root = (struct dx_root *) bh->b_data; 1988 1989 /* The 0th block becomes the root, move the dirents out */ 1990 fde = &root->dotdot; 1991 de = (struct ext4_dir_entry_2 *)((char *)fde + 1992 ext4_rec_len_from_disk(fde->rec_len, blocksize)); 1993 if ((char *) de >= (((char *) root) + blocksize)) { 1994 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); 1995 brelse(bh); 1996 return -EFSCORRUPTED; 1997 } 1998 len = ((char *) root) + (blocksize - csum_size) - (char *) de; 1999 2000 /* Allocate new block for the 0th block's dirents */ 2001 bh2 = ext4_append(handle, dir, &block); 2002 if (IS_ERR(bh2)) { 2003 brelse(bh); 2004 return PTR_ERR(bh2); 2005 } 2006 ext4_set_inode_flag(dir, EXT4_INODE_INDEX); 2007 data1 = bh2->b_data; 2008 2009 memcpy (data1, de, len); 2010 de = (struct ext4_dir_entry_2 *) data1; 2011 top = data1 + len; 2012 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) 2013 de = de2; 2014 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 2015 (char *) de, 2016 blocksize); 2017 2018 if (csum_size) { 2019 t = EXT4_DIRENT_TAIL(data1, blocksize); 2020 initialize_dirent_tail(t, blocksize); 2021 } 2022 2023 /* Initialize the root; the dot dirents already exist */ 2024 de = (struct ext4_dir_entry_2 *) (&root->dotdot); 2025 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), 2026 blocksize); 2027 memset (&root->info, 0, sizeof(root->info)); 2028 root->info.info_length = sizeof(root->info); 2029 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 2030 entries = root->entries; 2031 dx_set_block(entries, 1); 2032 dx_set_count(entries, 1); 2033 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); 2034 2035 /* Initialize as for dx_probe */ 2036 fname->hinfo.hash_version = root->info.hash_version; 2037 if (fname->hinfo.hash_version <= DX_HASH_TEA) 2038 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 2039 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 2040 ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo); 2041 2042 memset(frames, 0, sizeof(frames)); 2043 frame = frames; 2044 frame->entries = entries; 2045 frame->at = entries; 2046 frame->bh = bh; 2047 bh = bh2; 2048 2049 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2050 if (retval) 2051 goto out_frames; 2052 retval = ext4_handle_dirty_dirent_node(handle, dir, bh); 2053 if (retval) 2054 goto out_frames; 2055 2056 de = do_split(handle,dir, &bh, frame, &fname->hinfo); 2057 if (IS_ERR(de)) { 2058 retval = PTR_ERR(de); 2059 goto out_frames; 2060 } 2061 dx_release(frames); 2062 2063 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh); 2064 brelse(bh); 2065 return retval; 2066 out_frames: 2067 /* 2068 * Even if the block split failed, we have to properly write 2069 * out all the changes we did so far. Otherwise we can end up 2070 * with corrupted filesystem. 2071 */ 2072 ext4_mark_inode_dirty(handle, dir); 2073 dx_release(frames); 2074 return retval; 2075 } 2076 2077 /* 2078 * ext4_add_entry() 2079 * 2080 * adds a file entry to the specified directory, using the same 2081 * semantics as ext4_find_entry(). It returns NULL if it failed. 2082 * 2083 * NOTE!! The inode part of 'de' is left at 0 - which means you 2084 * may not sleep between calling this and putting something into 2085 * the entry, as someone else might have used it while you slept. 2086 */ 2087 static int ext4_add_entry(handle_t *handle, struct dentry *dentry, 2088 struct inode *inode) 2089 { 2090 struct inode *dir = d_inode(dentry->d_parent); 2091 struct buffer_head *bh = NULL; 2092 struct ext4_dir_entry_2 *de; 2093 struct ext4_dir_entry_tail *t; 2094 struct super_block *sb; 2095 struct ext4_filename fname; 2096 int retval; 2097 int dx_fallback=0; 2098 unsigned blocksize; 2099 ext4_lblk_t block, blocks; 2100 int csum_size = 0; 2101 2102 if (ext4_has_metadata_csum(inode->i_sb)) 2103 csum_size = sizeof(struct ext4_dir_entry_tail); 2104 2105 sb = dir->i_sb; 2106 blocksize = sb->s_blocksize; 2107 if (!dentry->d_name.len) 2108 return -EINVAL; 2109 2110 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname); 2111 if (retval) 2112 return retval; 2113 2114 if (ext4_has_inline_data(dir)) { 2115 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode); 2116 if (retval < 0) 2117 goto out; 2118 if (retval == 1) { 2119 retval = 0; 2120 goto out; 2121 } 2122 } 2123 2124 if (is_dx(dir)) { 2125 retval = ext4_dx_add_entry(handle, &fname, dir, inode); 2126 if (!retval || (retval != ERR_BAD_DX_DIR)) 2127 goto out; 2128 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); 2129 dx_fallback++; 2130 ext4_mark_inode_dirty(handle, dir); 2131 } 2132 blocks = dir->i_size >> sb->s_blocksize_bits; 2133 for (block = 0; block < blocks; block++) { 2134 bh = ext4_read_dirblock(dir, block, DIRENT); 2135 if (IS_ERR(bh)) { 2136 retval = PTR_ERR(bh); 2137 bh = NULL; 2138 goto out; 2139 } 2140 retval = add_dirent_to_buf(handle, &fname, dir, inode, 2141 NULL, bh); 2142 if (retval != -ENOSPC) 2143 goto out; 2144 2145 if (blocks == 1 && !dx_fallback && 2146 ext4_has_feature_dir_index(sb)) { 2147 retval = make_indexed_dir(handle, &fname, dir, 2148 inode, bh); 2149 bh = NULL; /* make_indexed_dir releases bh */ 2150 goto out; 2151 } 2152 brelse(bh); 2153 } 2154 bh = ext4_append(handle, dir, &block); 2155 if (IS_ERR(bh)) { 2156 retval = PTR_ERR(bh); 2157 bh = NULL; 2158 goto out; 2159 } 2160 de = (struct ext4_dir_entry_2 *) bh->b_data; 2161 de->inode = 0; 2162 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize); 2163 2164 if (csum_size) { 2165 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize); 2166 initialize_dirent_tail(t, blocksize); 2167 } 2168 2169 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh); 2170 out: 2171 ext4_fname_free_filename(&fname); 2172 brelse(bh); 2173 if (retval == 0) 2174 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); 2175 return retval; 2176 } 2177 2178 /* 2179 * Returns 0 for success, or a negative error value 2180 */ 2181 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 2182 struct inode *dir, struct inode *inode) 2183 { 2184 struct dx_frame frames[2], *frame; 2185 struct dx_entry *entries, *at; 2186 struct buffer_head *bh; 2187 struct super_block *sb = dir->i_sb; 2188 struct ext4_dir_entry_2 *de; 2189 int err; 2190 2191 frame = dx_probe(fname, dir, NULL, frames); 2192 if (IS_ERR(frame)) 2193 return PTR_ERR(frame); 2194 entries = frame->entries; 2195 at = frame->at; 2196 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT); 2197 if (IS_ERR(bh)) { 2198 err = PTR_ERR(bh); 2199 bh = NULL; 2200 goto cleanup; 2201 } 2202 2203 BUFFER_TRACE(bh, "get_write_access"); 2204 err = ext4_journal_get_write_access(handle, bh); 2205 if (err) 2206 goto journal_error; 2207 2208 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh); 2209 if (err != -ENOSPC) 2210 goto cleanup; 2211 2212 /* Block full, should compress but for now just split */ 2213 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n", 2214 dx_get_count(entries), dx_get_limit(entries))); 2215 /* Need to split index? */ 2216 if (dx_get_count(entries) == dx_get_limit(entries)) { 2217 ext4_lblk_t newblock; 2218 unsigned icount = dx_get_count(entries); 2219 int levels = frame - frames; 2220 struct dx_entry *entries2; 2221 struct dx_node *node2; 2222 struct buffer_head *bh2; 2223 2224 if (levels && (dx_get_count(frames->entries) == 2225 dx_get_limit(frames->entries))) { 2226 ext4_warning_inode(dir, "Directory index full!"); 2227 err = -ENOSPC; 2228 goto cleanup; 2229 } 2230 bh2 = ext4_append(handle, dir, &newblock); 2231 if (IS_ERR(bh2)) { 2232 err = PTR_ERR(bh2); 2233 goto cleanup; 2234 } 2235 node2 = (struct dx_node *)(bh2->b_data); 2236 entries2 = node2->entries; 2237 memset(&node2->fake, 0, sizeof(struct fake_dirent)); 2238 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, 2239 sb->s_blocksize); 2240 BUFFER_TRACE(frame->bh, "get_write_access"); 2241 err = ext4_journal_get_write_access(handle, frame->bh); 2242 if (err) 2243 goto journal_error; 2244 if (levels) { 2245 unsigned icount1 = icount/2, icount2 = icount - icount1; 2246 unsigned hash2 = dx_get_hash(entries + icount1); 2247 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n", 2248 icount1, icount2)); 2249 2250 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 2251 err = ext4_journal_get_write_access(handle, 2252 frames[0].bh); 2253 if (err) 2254 goto journal_error; 2255 2256 memcpy((char *) entries2, (char *) (entries + icount1), 2257 icount2 * sizeof(struct dx_entry)); 2258 dx_set_count(entries, icount1); 2259 dx_set_count(entries2, icount2); 2260 dx_set_limit(entries2, dx_node_limit(dir)); 2261 2262 /* Which index block gets the new entry? */ 2263 if (at - entries >= icount1) { 2264 frame->at = at = at - entries - icount1 + entries2; 2265 frame->entries = entries = entries2; 2266 swap(frame->bh, bh2); 2267 } 2268 dx_insert_block(frames + 0, hash2, newblock); 2269 dxtrace(dx_show_index("node", frames[1].entries)); 2270 dxtrace(dx_show_index("node", 2271 ((struct dx_node *) bh2->b_data)->entries)); 2272 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2273 if (err) 2274 goto journal_error; 2275 brelse (bh2); 2276 } else { 2277 dxtrace(printk(KERN_DEBUG 2278 "Creating second level index...\n")); 2279 memcpy((char *) entries2, (char *) entries, 2280 icount * sizeof(struct dx_entry)); 2281 dx_set_limit(entries2, dx_node_limit(dir)); 2282 2283 /* Set up root */ 2284 dx_set_count(entries, 1); 2285 dx_set_block(entries + 0, newblock); 2286 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1; 2287 2288 /* Add new access path frame */ 2289 frame = frames + 1; 2290 frame->at = at = at - entries + entries2; 2291 frame->entries = entries = entries2; 2292 frame->bh = bh2; 2293 err = ext4_journal_get_write_access(handle, 2294 frame->bh); 2295 if (err) 2296 goto journal_error; 2297 } 2298 err = ext4_handle_dirty_dx_node(handle, dir, frames[0].bh); 2299 if (err) { 2300 ext4_std_error(inode->i_sb, err); 2301 goto cleanup; 2302 } 2303 } 2304 de = do_split(handle, dir, &bh, frame, &fname->hinfo); 2305 if (IS_ERR(de)) { 2306 err = PTR_ERR(de); 2307 goto cleanup; 2308 } 2309 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh); 2310 goto cleanup; 2311 2312 journal_error: 2313 ext4_std_error(dir->i_sb, err); 2314 cleanup: 2315 brelse(bh); 2316 dx_release(frames); 2317 return err; 2318 } 2319 2320 /* 2321 * ext4_generic_delete_entry deletes a directory entry by merging it 2322 * with the previous entry 2323 */ 2324 int ext4_generic_delete_entry(handle_t *handle, 2325 struct inode *dir, 2326 struct ext4_dir_entry_2 *de_del, 2327 struct buffer_head *bh, 2328 void *entry_buf, 2329 int buf_size, 2330 int csum_size) 2331 { 2332 struct ext4_dir_entry_2 *de, *pde; 2333 unsigned int blocksize = dir->i_sb->s_blocksize; 2334 int i; 2335 2336 i = 0; 2337 pde = NULL; 2338 de = (struct ext4_dir_entry_2 *)entry_buf; 2339 while (i < buf_size - csum_size) { 2340 if (ext4_check_dir_entry(dir, NULL, de, bh, 2341 bh->b_data, bh->b_size, i)) 2342 return -EFSCORRUPTED; 2343 if (de == de_del) { 2344 if (pde) 2345 pde->rec_len = ext4_rec_len_to_disk( 2346 ext4_rec_len_from_disk(pde->rec_len, 2347 blocksize) + 2348 ext4_rec_len_from_disk(de->rec_len, 2349 blocksize), 2350 blocksize); 2351 else 2352 de->inode = 0; 2353 dir->i_version++; 2354 return 0; 2355 } 2356 i += ext4_rec_len_from_disk(de->rec_len, blocksize); 2357 pde = de; 2358 de = ext4_next_entry(de, blocksize); 2359 } 2360 return -ENOENT; 2361 } 2362 2363 static int ext4_delete_entry(handle_t *handle, 2364 struct inode *dir, 2365 struct ext4_dir_entry_2 *de_del, 2366 struct buffer_head *bh) 2367 { 2368 int err, csum_size = 0; 2369 2370 if (ext4_has_inline_data(dir)) { 2371 int has_inline_data = 1; 2372 err = ext4_delete_inline_entry(handle, dir, de_del, bh, 2373 &has_inline_data); 2374 if (has_inline_data) 2375 return err; 2376 } 2377 2378 if (ext4_has_metadata_csum(dir->i_sb)) 2379 csum_size = sizeof(struct ext4_dir_entry_tail); 2380 2381 BUFFER_TRACE(bh, "get_write_access"); 2382 err = ext4_journal_get_write_access(handle, bh); 2383 if (unlikely(err)) 2384 goto out; 2385 2386 err = ext4_generic_delete_entry(handle, dir, de_del, 2387 bh, bh->b_data, 2388 dir->i_sb->s_blocksize, csum_size); 2389 if (err) 2390 goto out; 2391 2392 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 2393 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 2394 if (unlikely(err)) 2395 goto out; 2396 2397 return 0; 2398 out: 2399 if (err != -ENOENT) 2400 ext4_std_error(dir->i_sb, err); 2401 return err; 2402 } 2403 2404 /* 2405 * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2, 2406 * since this indicates that nlinks count was previously 1. 2407 */ 2408 static void ext4_inc_count(handle_t *handle, struct inode *inode) 2409 { 2410 inc_nlink(inode); 2411 if (is_dx(inode) && inode->i_nlink > 1) { 2412 /* limit is 16-bit i_links_count */ 2413 if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) { 2414 set_nlink(inode, 1); 2415 ext4_set_feature_dir_nlink(inode->i_sb); 2416 } 2417 } 2418 } 2419 2420 /* 2421 * If a directory had nlink == 1, then we should let it be 1. This indicates 2422 * directory has >EXT4_LINK_MAX subdirs. 2423 */ 2424 static void ext4_dec_count(handle_t *handle, struct inode *inode) 2425 { 2426 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) 2427 drop_nlink(inode); 2428 } 2429 2430 2431 static int ext4_add_nondir(handle_t *handle, 2432 struct dentry *dentry, struct inode *inode) 2433 { 2434 int err = ext4_add_entry(handle, dentry, inode); 2435 if (!err) { 2436 ext4_mark_inode_dirty(handle, inode); 2437 unlock_new_inode(inode); 2438 d_instantiate(dentry, inode); 2439 return 0; 2440 } 2441 drop_nlink(inode); 2442 unlock_new_inode(inode); 2443 iput(inode); 2444 return err; 2445 } 2446 2447 /* 2448 * By the time this is called, we already have created 2449 * the directory cache entry for the new file, but it 2450 * is so far negative - it has no inode. 2451 * 2452 * If the create succeeds, we fill in the inode information 2453 * with d_instantiate(). 2454 */ 2455 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, 2456 bool excl) 2457 { 2458 handle_t *handle; 2459 struct inode *inode; 2460 int err, credits, retries = 0; 2461 2462 err = dquot_initialize(dir); 2463 if (err) 2464 return err; 2465 2466 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2467 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2468 retry: 2469 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2470 NULL, EXT4_HT_DIR, credits); 2471 handle = ext4_journal_current_handle(); 2472 err = PTR_ERR(inode); 2473 if (!IS_ERR(inode)) { 2474 inode->i_op = &ext4_file_inode_operations; 2475 inode->i_fop = &ext4_file_operations; 2476 ext4_set_aops(inode); 2477 err = ext4_add_nondir(handle, dentry, inode); 2478 if (!err && IS_DIRSYNC(dir)) 2479 ext4_handle_sync(handle); 2480 } 2481 if (handle) 2482 ext4_journal_stop(handle); 2483 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2484 goto retry; 2485 return err; 2486 } 2487 2488 static int ext4_mknod(struct inode *dir, struct dentry *dentry, 2489 umode_t mode, dev_t rdev) 2490 { 2491 handle_t *handle; 2492 struct inode *inode; 2493 int err, credits, retries = 0; 2494 2495 err = dquot_initialize(dir); 2496 if (err) 2497 return err; 2498 2499 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2500 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2501 retry: 2502 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2503 NULL, EXT4_HT_DIR, credits); 2504 handle = ext4_journal_current_handle(); 2505 err = PTR_ERR(inode); 2506 if (!IS_ERR(inode)) { 2507 init_special_inode(inode, inode->i_mode, rdev); 2508 inode->i_op = &ext4_special_inode_operations; 2509 err = ext4_add_nondir(handle, dentry, inode); 2510 if (!err && IS_DIRSYNC(dir)) 2511 ext4_handle_sync(handle); 2512 } 2513 if (handle) 2514 ext4_journal_stop(handle); 2515 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2516 goto retry; 2517 return err; 2518 } 2519 2520 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 2521 { 2522 handle_t *handle; 2523 struct inode *inode; 2524 int err, retries = 0; 2525 2526 err = dquot_initialize(dir); 2527 if (err) 2528 return err; 2529 2530 retry: 2531 inode = ext4_new_inode_start_handle(dir, mode, 2532 NULL, 0, NULL, 2533 EXT4_HT_DIR, 2534 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 2535 4 + EXT4_XATTR_TRANS_BLOCKS); 2536 handle = ext4_journal_current_handle(); 2537 err = PTR_ERR(inode); 2538 if (!IS_ERR(inode)) { 2539 inode->i_op = &ext4_file_inode_operations; 2540 inode->i_fop = &ext4_file_operations; 2541 ext4_set_aops(inode); 2542 d_tmpfile(dentry, inode); 2543 err = ext4_orphan_add(handle, inode); 2544 if (err) 2545 goto err_unlock_inode; 2546 mark_inode_dirty(inode); 2547 unlock_new_inode(inode); 2548 } 2549 if (handle) 2550 ext4_journal_stop(handle); 2551 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2552 goto retry; 2553 return err; 2554 err_unlock_inode: 2555 ext4_journal_stop(handle); 2556 unlock_new_inode(inode); 2557 return err; 2558 } 2559 2560 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode, 2561 struct ext4_dir_entry_2 *de, 2562 int blocksize, int csum_size, 2563 unsigned int parent_ino, int dotdot_real_len) 2564 { 2565 de->inode = cpu_to_le32(inode->i_ino); 2566 de->name_len = 1; 2567 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), 2568 blocksize); 2569 strcpy(de->name, "."); 2570 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2571 2572 de = ext4_next_entry(de, blocksize); 2573 de->inode = cpu_to_le32(parent_ino); 2574 de->name_len = 2; 2575 if (!dotdot_real_len) 2576 de->rec_len = ext4_rec_len_to_disk(blocksize - 2577 (csum_size + EXT4_DIR_REC_LEN(1)), 2578 blocksize); 2579 else 2580 de->rec_len = ext4_rec_len_to_disk( 2581 EXT4_DIR_REC_LEN(de->name_len), blocksize); 2582 strcpy(de->name, ".."); 2583 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2584 2585 return ext4_next_entry(de, blocksize); 2586 } 2587 2588 static int ext4_init_new_dir(handle_t *handle, struct inode *dir, 2589 struct inode *inode) 2590 { 2591 struct buffer_head *dir_block = NULL; 2592 struct ext4_dir_entry_2 *de; 2593 struct ext4_dir_entry_tail *t; 2594 ext4_lblk_t block = 0; 2595 unsigned int blocksize = dir->i_sb->s_blocksize; 2596 int csum_size = 0; 2597 int err; 2598 2599 if (ext4_has_metadata_csum(dir->i_sb)) 2600 csum_size = sizeof(struct ext4_dir_entry_tail); 2601 2602 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { 2603 err = ext4_try_create_inline_dir(handle, dir, inode); 2604 if (err < 0 && err != -ENOSPC) 2605 goto out; 2606 if (!err) 2607 goto out; 2608 } 2609 2610 inode->i_size = 0; 2611 dir_block = ext4_append(handle, inode, &block); 2612 if (IS_ERR(dir_block)) 2613 return PTR_ERR(dir_block); 2614 de = (struct ext4_dir_entry_2 *)dir_block->b_data; 2615 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0); 2616 set_nlink(inode, 2); 2617 if (csum_size) { 2618 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize); 2619 initialize_dirent_tail(t, blocksize); 2620 } 2621 2622 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); 2623 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block); 2624 if (err) 2625 goto out; 2626 set_buffer_verified(dir_block); 2627 out: 2628 brelse(dir_block); 2629 return err; 2630 } 2631 2632 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2633 { 2634 handle_t *handle; 2635 struct inode *inode; 2636 int err, credits, retries = 0; 2637 2638 if (EXT4_DIR_LINK_MAX(dir)) 2639 return -EMLINK; 2640 2641 err = dquot_initialize(dir); 2642 if (err) 2643 return err; 2644 2645 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2646 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2647 retry: 2648 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode, 2649 &dentry->d_name, 2650 0, NULL, EXT4_HT_DIR, credits); 2651 handle = ext4_journal_current_handle(); 2652 err = PTR_ERR(inode); 2653 if (IS_ERR(inode)) 2654 goto out_stop; 2655 2656 inode->i_op = &ext4_dir_inode_operations; 2657 inode->i_fop = &ext4_dir_operations; 2658 err = ext4_init_new_dir(handle, dir, inode); 2659 if (err) 2660 goto out_clear_inode; 2661 err = ext4_mark_inode_dirty(handle, inode); 2662 if (!err) 2663 err = ext4_add_entry(handle, dentry, inode); 2664 if (err) { 2665 out_clear_inode: 2666 clear_nlink(inode); 2667 unlock_new_inode(inode); 2668 ext4_mark_inode_dirty(handle, inode); 2669 iput(inode); 2670 goto out_stop; 2671 } 2672 ext4_inc_count(handle, dir); 2673 ext4_update_dx_flag(dir); 2674 err = ext4_mark_inode_dirty(handle, dir); 2675 if (err) 2676 goto out_clear_inode; 2677 unlock_new_inode(inode); 2678 d_instantiate(dentry, inode); 2679 if (IS_DIRSYNC(dir)) 2680 ext4_handle_sync(handle); 2681 2682 out_stop: 2683 if (handle) 2684 ext4_journal_stop(handle); 2685 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2686 goto retry; 2687 return err; 2688 } 2689 2690 /* 2691 * routine to check that the specified directory is empty (for rmdir) 2692 */ 2693 bool ext4_empty_dir(struct inode *inode) 2694 { 2695 unsigned int offset; 2696 struct buffer_head *bh; 2697 struct ext4_dir_entry_2 *de, *de1; 2698 struct super_block *sb; 2699 2700 if (ext4_has_inline_data(inode)) { 2701 int has_inline_data = 1; 2702 int ret; 2703 2704 ret = empty_inline_dir(inode, &has_inline_data); 2705 if (has_inline_data) 2706 return ret; 2707 } 2708 2709 sb = inode->i_sb; 2710 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { 2711 EXT4_ERROR_INODE(inode, "invalid size"); 2712 return true; 2713 } 2714 bh = ext4_read_dirblock(inode, 0, EITHER); 2715 if (IS_ERR(bh)) 2716 return true; 2717 2718 de = (struct ext4_dir_entry_2 *) bh->b_data; 2719 de1 = ext4_next_entry(de, sb->s_blocksize); 2720 if (le32_to_cpu(de->inode) != inode->i_ino || 2721 le32_to_cpu(de1->inode) == 0 || 2722 strcmp(".", de->name) || strcmp("..", de1->name)) { 2723 ext4_warning_inode(inode, "directory missing '.' and/or '..'"); 2724 brelse(bh); 2725 return true; 2726 } 2727 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + 2728 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); 2729 de = ext4_next_entry(de1, sb->s_blocksize); 2730 while (offset < inode->i_size) { 2731 if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 2732 unsigned int lblock; 2733 brelse(bh); 2734 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); 2735 bh = ext4_read_dirblock(inode, lblock, EITHER); 2736 if (IS_ERR(bh)) 2737 return true; 2738 de = (struct ext4_dir_entry_2 *) bh->b_data; 2739 } 2740 if (ext4_check_dir_entry(inode, NULL, de, bh, 2741 bh->b_data, bh->b_size, offset)) { 2742 de = (struct ext4_dir_entry_2 *)(bh->b_data + 2743 sb->s_blocksize); 2744 offset = (offset | (sb->s_blocksize - 1)) + 1; 2745 continue; 2746 } 2747 if (le32_to_cpu(de->inode)) { 2748 brelse(bh); 2749 return false; 2750 } 2751 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2752 de = ext4_next_entry(de, sb->s_blocksize); 2753 } 2754 brelse(bh); 2755 return true; 2756 } 2757 2758 /* 2759 * ext4_orphan_add() links an unlinked or truncated inode into a list of 2760 * such inodes, starting at the superblock, in case we crash before the 2761 * file is closed/deleted, or in case the inode truncate spans multiple 2762 * transactions and the last transaction is not recovered after a crash. 2763 * 2764 * At filesystem recovery time, we walk this list deleting unlinked 2765 * inodes and truncating linked inodes in ext4_orphan_cleanup(). 2766 * 2767 * Orphan list manipulation functions must be called under i_mutex unless 2768 * we are just creating the inode or deleting it. 2769 */ 2770 int ext4_orphan_add(handle_t *handle, struct inode *inode) 2771 { 2772 struct super_block *sb = inode->i_sb; 2773 struct ext4_sb_info *sbi = EXT4_SB(sb); 2774 struct ext4_iloc iloc; 2775 int err = 0, rc; 2776 bool dirty = false; 2777 2778 if (!sbi->s_journal || is_bad_inode(inode)) 2779 return 0; 2780 2781 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2782 !inode_is_locked(inode)); 2783 /* 2784 * Exit early if inode already is on orphan list. This is a big speedup 2785 * since we don't have to contend on the global s_orphan_lock. 2786 */ 2787 if (!list_empty(&EXT4_I(inode)->i_orphan)) 2788 return 0; 2789 2790 /* 2791 * Orphan handling is only valid for files with data blocks 2792 * being truncated, or files being unlinked. Note that we either 2793 * hold i_mutex, or the inode can not be referenced from outside, 2794 * so i_nlink should not be bumped due to race 2795 */ 2796 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2797 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 2798 2799 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2800 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2801 if (err) 2802 goto out; 2803 2804 err = ext4_reserve_inode_write(handle, inode, &iloc); 2805 if (err) 2806 goto out; 2807 2808 mutex_lock(&sbi->s_orphan_lock); 2809 /* 2810 * Due to previous errors inode may be already a part of on-disk 2811 * orphan list. If so skip on-disk list modification. 2812 */ 2813 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) > 2814 (le32_to_cpu(sbi->s_es->s_inodes_count))) { 2815 /* Insert this inode at the head of the on-disk orphan list */ 2816 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan); 2817 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 2818 dirty = true; 2819 } 2820 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan); 2821 mutex_unlock(&sbi->s_orphan_lock); 2822 2823 if (dirty) { 2824 err = ext4_handle_dirty_super(handle, sb); 2825 rc = ext4_mark_iloc_dirty(handle, inode, &iloc); 2826 if (!err) 2827 err = rc; 2828 if (err) { 2829 /* 2830 * We have to remove inode from in-memory list if 2831 * addition to on disk orphan list failed. Stray orphan 2832 * list entries can cause panics at unmount time. 2833 */ 2834 mutex_lock(&sbi->s_orphan_lock); 2835 list_del_init(&EXT4_I(inode)->i_orphan); 2836 mutex_unlock(&sbi->s_orphan_lock); 2837 } 2838 } 2839 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 2840 jbd_debug(4, "orphan inode %lu will point to %d\n", 2841 inode->i_ino, NEXT_ORPHAN(inode)); 2842 out: 2843 ext4_std_error(sb, err); 2844 return err; 2845 } 2846 2847 /* 2848 * ext4_orphan_del() removes an unlinked or truncated inode from the list 2849 * of such inodes stored on disk, because it is finally being cleaned up. 2850 */ 2851 int ext4_orphan_del(handle_t *handle, struct inode *inode) 2852 { 2853 struct list_head *prev; 2854 struct ext4_inode_info *ei = EXT4_I(inode); 2855 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 2856 __u32 ino_next; 2857 struct ext4_iloc iloc; 2858 int err = 0; 2859 2860 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS)) 2861 return 0; 2862 2863 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2864 !inode_is_locked(inode)); 2865 /* Do this quick check before taking global s_orphan_lock. */ 2866 if (list_empty(&ei->i_orphan)) 2867 return 0; 2868 2869 if (handle) { 2870 /* Grab inode buffer early before taking global s_orphan_lock */ 2871 err = ext4_reserve_inode_write(handle, inode, &iloc); 2872 } 2873 2874 mutex_lock(&sbi->s_orphan_lock); 2875 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 2876 2877 prev = ei->i_orphan.prev; 2878 list_del_init(&ei->i_orphan); 2879 2880 /* If we're on an error path, we may not have a valid 2881 * transaction handle with which to update the orphan list on 2882 * disk, but we still need to remove the inode from the linked 2883 * list in memory. */ 2884 if (!handle || err) { 2885 mutex_unlock(&sbi->s_orphan_lock); 2886 goto out_err; 2887 } 2888 2889 ino_next = NEXT_ORPHAN(inode); 2890 if (prev == &sbi->s_orphan) { 2891 jbd_debug(4, "superblock will point to %u\n", ino_next); 2892 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2893 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2894 if (err) { 2895 mutex_unlock(&sbi->s_orphan_lock); 2896 goto out_brelse; 2897 } 2898 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 2899 mutex_unlock(&sbi->s_orphan_lock); 2900 err = ext4_handle_dirty_super(handle, inode->i_sb); 2901 } else { 2902 struct ext4_iloc iloc2; 2903 struct inode *i_prev = 2904 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; 2905 2906 jbd_debug(4, "orphan inode %lu will point to %u\n", 2907 i_prev->i_ino, ino_next); 2908 err = ext4_reserve_inode_write(handle, i_prev, &iloc2); 2909 if (err) { 2910 mutex_unlock(&sbi->s_orphan_lock); 2911 goto out_brelse; 2912 } 2913 NEXT_ORPHAN(i_prev) = ino_next; 2914 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); 2915 mutex_unlock(&sbi->s_orphan_lock); 2916 } 2917 if (err) 2918 goto out_brelse; 2919 NEXT_ORPHAN(inode) = 0; 2920 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 2921 out_err: 2922 ext4_std_error(inode->i_sb, err); 2923 return err; 2924 2925 out_brelse: 2926 brelse(iloc.bh); 2927 goto out_err; 2928 } 2929 2930 static int ext4_rmdir(struct inode *dir, struct dentry *dentry) 2931 { 2932 int retval; 2933 struct inode *inode; 2934 struct buffer_head *bh; 2935 struct ext4_dir_entry_2 *de; 2936 handle_t *handle = NULL; 2937 2938 /* Initialize quotas before so that eventual writes go in 2939 * separate transaction */ 2940 retval = dquot_initialize(dir); 2941 if (retval) 2942 return retval; 2943 retval = dquot_initialize(d_inode(dentry)); 2944 if (retval) 2945 return retval; 2946 2947 retval = -ENOENT; 2948 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 2949 if (IS_ERR(bh)) 2950 return PTR_ERR(bh); 2951 if (!bh) 2952 goto end_rmdir; 2953 2954 inode = d_inode(dentry); 2955 2956 retval = -EFSCORRUPTED; 2957 if (le32_to_cpu(de->inode) != inode->i_ino) 2958 goto end_rmdir; 2959 2960 retval = -ENOTEMPTY; 2961 if (!ext4_empty_dir(inode)) 2962 goto end_rmdir; 2963 2964 handle = ext4_journal_start(dir, EXT4_HT_DIR, 2965 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 2966 if (IS_ERR(handle)) { 2967 retval = PTR_ERR(handle); 2968 handle = NULL; 2969 goto end_rmdir; 2970 } 2971 2972 if (IS_DIRSYNC(dir)) 2973 ext4_handle_sync(handle); 2974 2975 retval = ext4_delete_entry(handle, dir, de, bh); 2976 if (retval) 2977 goto end_rmdir; 2978 if (!EXT4_DIR_LINK_EMPTY(inode)) 2979 ext4_warning_inode(inode, 2980 "empty directory '%.*s' has too many links (%u)", 2981 dentry->d_name.len, dentry->d_name.name, 2982 inode->i_nlink); 2983 inode->i_version++; 2984 clear_nlink(inode); 2985 /* There's no need to set i_disksize: the fact that i_nlink is 2986 * zero will ensure that the right thing happens during any 2987 * recovery. */ 2988 inode->i_size = 0; 2989 ext4_orphan_add(handle, inode); 2990 inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode); 2991 ext4_mark_inode_dirty(handle, inode); 2992 ext4_dec_count(handle, dir); 2993 ext4_update_dx_flag(dir); 2994 ext4_mark_inode_dirty(handle, dir); 2995 2996 end_rmdir: 2997 brelse(bh); 2998 if (handle) 2999 ext4_journal_stop(handle); 3000 return retval; 3001 } 3002 3003 static int ext4_unlink(struct inode *dir, struct dentry *dentry) 3004 { 3005 int retval; 3006 struct inode *inode; 3007 struct buffer_head *bh; 3008 struct ext4_dir_entry_2 *de; 3009 handle_t *handle = NULL; 3010 3011 trace_ext4_unlink_enter(dir, dentry); 3012 /* Initialize quotas before so that eventual writes go 3013 * in separate transaction */ 3014 retval = dquot_initialize(dir); 3015 if (retval) 3016 return retval; 3017 retval = dquot_initialize(d_inode(dentry)); 3018 if (retval) 3019 return retval; 3020 3021 retval = -ENOENT; 3022 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 3023 if (IS_ERR(bh)) 3024 return PTR_ERR(bh); 3025 if (!bh) 3026 goto end_unlink; 3027 3028 inode = d_inode(dentry); 3029 3030 retval = -EFSCORRUPTED; 3031 if (le32_to_cpu(de->inode) != inode->i_ino) 3032 goto end_unlink; 3033 3034 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3035 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 3036 if (IS_ERR(handle)) { 3037 retval = PTR_ERR(handle); 3038 handle = NULL; 3039 goto end_unlink; 3040 } 3041 3042 if (IS_DIRSYNC(dir)) 3043 ext4_handle_sync(handle); 3044 3045 if (inode->i_nlink == 0) { 3046 ext4_warning_inode(inode, "Deleting file '%.*s' with no links", 3047 dentry->d_name.len, dentry->d_name.name); 3048 set_nlink(inode, 1); 3049 } 3050 retval = ext4_delete_entry(handle, dir, de, bh); 3051 if (retval) 3052 goto end_unlink; 3053 dir->i_ctime = dir->i_mtime = ext4_current_time(dir); 3054 ext4_update_dx_flag(dir); 3055 ext4_mark_inode_dirty(handle, dir); 3056 drop_nlink(inode); 3057 if (!inode->i_nlink) 3058 ext4_orphan_add(handle, inode); 3059 inode->i_ctime = ext4_current_time(inode); 3060 ext4_mark_inode_dirty(handle, inode); 3061 3062 end_unlink: 3063 brelse(bh); 3064 if (handle) 3065 ext4_journal_stop(handle); 3066 trace_ext4_unlink_exit(dentry, retval); 3067 return retval; 3068 } 3069 3070 static int ext4_symlink(struct inode *dir, 3071 struct dentry *dentry, const char *symname) 3072 { 3073 handle_t *handle; 3074 struct inode *inode; 3075 int err, len = strlen(symname); 3076 int credits; 3077 bool encryption_required; 3078 struct fscrypt_str disk_link; 3079 struct fscrypt_symlink_data *sd = NULL; 3080 3081 disk_link.len = len + 1; 3082 disk_link.name = (char *) symname; 3083 3084 encryption_required = (ext4_encrypted_inode(dir) || 3085 DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb))); 3086 if (encryption_required) { 3087 err = fscrypt_get_encryption_info(dir); 3088 if (err) 3089 return err; 3090 if (!fscrypt_has_encryption_key(dir)) 3091 return -EPERM; 3092 disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + 3093 sizeof(struct fscrypt_symlink_data)); 3094 sd = kzalloc(disk_link.len, GFP_KERNEL); 3095 if (!sd) 3096 return -ENOMEM; 3097 } 3098 3099 if (disk_link.len > dir->i_sb->s_blocksize) { 3100 err = -ENAMETOOLONG; 3101 goto err_free_sd; 3102 } 3103 3104 err = dquot_initialize(dir); 3105 if (err) 3106 goto err_free_sd; 3107 3108 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3109 /* 3110 * For non-fast symlinks, we just allocate inode and put it on 3111 * orphan list in the first transaction => we need bitmap, 3112 * group descriptor, sb, inode block, quota blocks, and 3113 * possibly selinux xattr blocks. 3114 */ 3115 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 3116 EXT4_XATTR_TRANS_BLOCKS; 3117 } else { 3118 /* 3119 * Fast symlink. We have to add entry to directory 3120 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), 3121 * allocate new inode (bitmap, group descriptor, inode block, 3122 * quota blocks, sb is already counted in previous macros). 3123 */ 3124 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3125 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3; 3126 } 3127 3128 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO, 3129 &dentry->d_name, 0, NULL, 3130 EXT4_HT_DIR, credits); 3131 handle = ext4_journal_current_handle(); 3132 if (IS_ERR(inode)) { 3133 if (handle) 3134 ext4_journal_stop(handle); 3135 err = PTR_ERR(inode); 3136 goto err_free_sd; 3137 } 3138 3139 if (encryption_required) { 3140 struct qstr istr; 3141 struct fscrypt_str ostr = 3142 FSTR_INIT(sd->encrypted_path, disk_link.len); 3143 3144 istr.name = (const unsigned char *) symname; 3145 istr.len = len; 3146 err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); 3147 if (err < 0) 3148 goto err_drop_inode; 3149 sd->len = cpu_to_le16(ostr.len); 3150 disk_link.name = (char *) sd; 3151 inode->i_op = &ext4_encrypted_symlink_inode_operations; 3152 } 3153 3154 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3155 if (!encryption_required) 3156 inode->i_op = &ext4_symlink_inode_operations; 3157 inode_nohighmem(inode); 3158 ext4_set_aops(inode); 3159 /* 3160 * We cannot call page_symlink() with transaction started 3161 * because it calls into ext4_write_begin() which can wait 3162 * for transaction commit if we are running out of space 3163 * and thus we deadlock. So we have to stop transaction now 3164 * and restart it when symlink contents is written. 3165 * 3166 * To keep fs consistent in case of crash, we have to put inode 3167 * to orphan list in the mean time. 3168 */ 3169 drop_nlink(inode); 3170 err = ext4_orphan_add(handle, inode); 3171 ext4_journal_stop(handle); 3172 handle = NULL; 3173 if (err) 3174 goto err_drop_inode; 3175 err = __page_symlink(inode, disk_link.name, disk_link.len, 1); 3176 if (err) 3177 goto err_drop_inode; 3178 /* 3179 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS 3180 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified 3181 */ 3182 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3183 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3184 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); 3185 if (IS_ERR(handle)) { 3186 err = PTR_ERR(handle); 3187 handle = NULL; 3188 goto err_drop_inode; 3189 } 3190 set_nlink(inode, 1); 3191 err = ext4_orphan_del(handle, inode); 3192 if (err) 3193 goto err_drop_inode; 3194 } else { 3195 /* clear the extent format for fast symlink */ 3196 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); 3197 if (!encryption_required) { 3198 inode->i_op = &ext4_fast_symlink_inode_operations; 3199 inode->i_link = (char *)&EXT4_I(inode)->i_data; 3200 } 3201 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name, 3202 disk_link.len); 3203 inode->i_size = disk_link.len - 1; 3204 } 3205 EXT4_I(inode)->i_disksize = inode->i_size; 3206 err = ext4_add_nondir(handle, dentry, inode); 3207 if (!err && IS_DIRSYNC(dir)) 3208 ext4_handle_sync(handle); 3209 3210 if (handle) 3211 ext4_journal_stop(handle); 3212 kfree(sd); 3213 return err; 3214 err_drop_inode: 3215 if (handle) 3216 ext4_journal_stop(handle); 3217 clear_nlink(inode); 3218 unlock_new_inode(inode); 3219 iput(inode); 3220 err_free_sd: 3221 kfree(sd); 3222 return err; 3223 } 3224 3225 static int ext4_link(struct dentry *old_dentry, 3226 struct inode *dir, struct dentry *dentry) 3227 { 3228 handle_t *handle; 3229 struct inode *inode = d_inode(old_dentry); 3230 int err, retries = 0; 3231 3232 if (inode->i_nlink >= EXT4_LINK_MAX) 3233 return -EMLINK; 3234 if (ext4_encrypted_inode(dir) && 3235 !fscrypt_has_permitted_context(dir, inode)) 3236 return -EPERM; 3237 3238 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) && 3239 (!projid_eq(EXT4_I(dir)->i_projid, 3240 EXT4_I(old_dentry->d_inode)->i_projid))) 3241 return -EXDEV; 3242 3243 err = dquot_initialize(dir); 3244 if (err) 3245 return err; 3246 3247 retry: 3248 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3249 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3250 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1); 3251 if (IS_ERR(handle)) 3252 return PTR_ERR(handle); 3253 3254 if (IS_DIRSYNC(dir)) 3255 ext4_handle_sync(handle); 3256 3257 inode->i_ctime = ext4_current_time(inode); 3258 ext4_inc_count(handle, inode); 3259 ihold(inode); 3260 3261 err = ext4_add_entry(handle, dentry, inode); 3262 if (!err) { 3263 ext4_mark_inode_dirty(handle, inode); 3264 /* this can happen only for tmpfile being 3265 * linked the first time 3266 */ 3267 if (inode->i_nlink == 1) 3268 ext4_orphan_del(handle, inode); 3269 d_instantiate(dentry, inode); 3270 } else { 3271 drop_nlink(inode); 3272 iput(inode); 3273 } 3274 ext4_journal_stop(handle); 3275 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 3276 goto retry; 3277 return err; 3278 } 3279 3280 3281 /* 3282 * Try to find buffer head where contains the parent block. 3283 * It should be the inode block if it is inlined or the 1st block 3284 * if it is a normal dir. 3285 */ 3286 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, 3287 struct inode *inode, 3288 int *retval, 3289 struct ext4_dir_entry_2 **parent_de, 3290 int *inlined) 3291 { 3292 struct buffer_head *bh; 3293 3294 if (!ext4_has_inline_data(inode)) { 3295 bh = ext4_read_dirblock(inode, 0, EITHER); 3296 if (IS_ERR(bh)) { 3297 *retval = PTR_ERR(bh); 3298 return NULL; 3299 } 3300 *parent_de = ext4_next_entry( 3301 (struct ext4_dir_entry_2 *)bh->b_data, 3302 inode->i_sb->s_blocksize); 3303 return bh; 3304 } 3305 3306 *inlined = 1; 3307 return ext4_get_first_inline_block(inode, parent_de, retval); 3308 } 3309 3310 struct ext4_renament { 3311 struct inode *dir; 3312 struct dentry *dentry; 3313 struct inode *inode; 3314 bool is_dir; 3315 int dir_nlink_delta; 3316 3317 /* entry for "dentry" */ 3318 struct buffer_head *bh; 3319 struct ext4_dir_entry_2 *de; 3320 int inlined; 3321 3322 /* entry for ".." in inode if it's a directory */ 3323 struct buffer_head *dir_bh; 3324 struct ext4_dir_entry_2 *parent_de; 3325 int dir_inlined; 3326 }; 3327 3328 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) 3329 { 3330 int retval; 3331 3332 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, 3333 &retval, &ent->parent_de, 3334 &ent->dir_inlined); 3335 if (!ent->dir_bh) 3336 return retval; 3337 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) 3338 return -EFSCORRUPTED; 3339 BUFFER_TRACE(ent->dir_bh, "get_write_access"); 3340 return ext4_journal_get_write_access(handle, ent->dir_bh); 3341 } 3342 3343 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, 3344 unsigned dir_ino) 3345 { 3346 int retval; 3347 3348 ent->parent_de->inode = cpu_to_le32(dir_ino); 3349 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); 3350 if (!ent->dir_inlined) { 3351 if (is_dx(ent->inode)) { 3352 retval = ext4_handle_dirty_dx_node(handle, 3353 ent->inode, 3354 ent->dir_bh); 3355 } else { 3356 retval = ext4_handle_dirty_dirent_node(handle, 3357 ent->inode, 3358 ent->dir_bh); 3359 } 3360 } else { 3361 retval = ext4_mark_inode_dirty(handle, ent->inode); 3362 } 3363 if (retval) { 3364 ext4_std_error(ent->dir->i_sb, retval); 3365 return retval; 3366 } 3367 return 0; 3368 } 3369 3370 static int ext4_setent(handle_t *handle, struct ext4_renament *ent, 3371 unsigned ino, unsigned file_type) 3372 { 3373 int retval; 3374 3375 BUFFER_TRACE(ent->bh, "get write access"); 3376 retval = ext4_journal_get_write_access(handle, ent->bh); 3377 if (retval) 3378 return retval; 3379 ent->de->inode = cpu_to_le32(ino); 3380 if (ext4_has_feature_filetype(ent->dir->i_sb)) 3381 ent->de->file_type = file_type; 3382 ent->dir->i_version++; 3383 ent->dir->i_ctime = ent->dir->i_mtime = 3384 ext4_current_time(ent->dir); 3385 ext4_mark_inode_dirty(handle, ent->dir); 3386 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); 3387 if (!ent->inlined) { 3388 retval = ext4_handle_dirty_dirent_node(handle, 3389 ent->dir, ent->bh); 3390 if (unlikely(retval)) { 3391 ext4_std_error(ent->dir->i_sb, retval); 3392 return retval; 3393 } 3394 } 3395 brelse(ent->bh); 3396 ent->bh = NULL; 3397 3398 return 0; 3399 } 3400 3401 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, 3402 const struct qstr *d_name) 3403 { 3404 int retval = -ENOENT; 3405 struct buffer_head *bh; 3406 struct ext4_dir_entry_2 *de; 3407 3408 bh = ext4_find_entry(dir, d_name, &de, NULL); 3409 if (IS_ERR(bh)) 3410 return PTR_ERR(bh); 3411 if (bh) { 3412 retval = ext4_delete_entry(handle, dir, de, bh); 3413 brelse(bh); 3414 } 3415 return retval; 3416 } 3417 3418 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent, 3419 int force_reread) 3420 { 3421 int retval; 3422 /* 3423 * ent->de could have moved from under us during htree split, so make 3424 * sure that we are deleting the right entry. We might also be pointing 3425 * to a stale entry in the unused part of ent->bh so just checking inum 3426 * and the name isn't enough. 3427 */ 3428 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || 3429 ent->de->name_len != ent->dentry->d_name.len || 3430 strncmp(ent->de->name, ent->dentry->d_name.name, 3431 ent->de->name_len) || 3432 force_reread) { 3433 retval = ext4_find_delete_entry(handle, ent->dir, 3434 &ent->dentry->d_name); 3435 } else { 3436 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); 3437 if (retval == -ENOENT) { 3438 retval = ext4_find_delete_entry(handle, ent->dir, 3439 &ent->dentry->d_name); 3440 } 3441 } 3442 3443 if (retval) { 3444 ext4_warning_inode(ent->dir, 3445 "Deleting old file: nlink %d, error=%d", 3446 ent->dir->i_nlink, retval); 3447 } 3448 } 3449 3450 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) 3451 { 3452 if (ent->dir_nlink_delta) { 3453 if (ent->dir_nlink_delta == -1) 3454 ext4_dec_count(handle, ent->dir); 3455 else 3456 ext4_inc_count(handle, ent->dir); 3457 ext4_mark_inode_dirty(handle, ent->dir); 3458 } 3459 } 3460 3461 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, 3462 int credits, handle_t **h) 3463 { 3464 struct inode *wh; 3465 handle_t *handle; 3466 int retries = 0; 3467 3468 /* 3469 * for inode block, sb block, group summaries, 3470 * and inode bitmap 3471 */ 3472 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + 3473 EXT4_XATTR_TRANS_BLOCKS + 4); 3474 retry: 3475 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, 3476 &ent->dentry->d_name, 0, NULL, 3477 EXT4_HT_DIR, credits); 3478 3479 handle = ext4_journal_current_handle(); 3480 if (IS_ERR(wh)) { 3481 if (handle) 3482 ext4_journal_stop(handle); 3483 if (PTR_ERR(wh) == -ENOSPC && 3484 ext4_should_retry_alloc(ent->dir->i_sb, &retries)) 3485 goto retry; 3486 } else { 3487 *h = handle; 3488 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); 3489 wh->i_op = &ext4_special_inode_operations; 3490 } 3491 return wh; 3492 } 3493 3494 /* 3495 * Anybody can rename anything with this: the permission checks are left to the 3496 * higher-level routines. 3497 * 3498 * n.b. old_{dentry,inode) refers to the source dentry/inode 3499 * while new_{dentry,inode) refers to the destination dentry/inode 3500 * This comes from rename(const char *oldpath, const char *newpath) 3501 */ 3502 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, 3503 struct inode *new_dir, struct dentry *new_dentry, 3504 unsigned int flags) 3505 { 3506 handle_t *handle = NULL; 3507 struct ext4_renament old = { 3508 .dir = old_dir, 3509 .dentry = old_dentry, 3510 .inode = d_inode(old_dentry), 3511 }; 3512 struct ext4_renament new = { 3513 .dir = new_dir, 3514 .dentry = new_dentry, 3515 .inode = d_inode(new_dentry), 3516 }; 3517 int force_reread; 3518 int retval; 3519 struct inode *whiteout = NULL; 3520 int credits; 3521 u8 old_file_type; 3522 3523 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && 3524 (!projid_eq(EXT4_I(new_dir)->i_projid, 3525 EXT4_I(old_dentry->d_inode)->i_projid))) 3526 return -EXDEV; 3527 3528 retval = dquot_initialize(old.dir); 3529 if (retval) 3530 return retval; 3531 retval = dquot_initialize(new.dir); 3532 if (retval) 3533 return retval; 3534 3535 /* Initialize quotas before so that eventual writes go 3536 * in separate transaction */ 3537 if (new.inode) { 3538 retval = dquot_initialize(new.inode); 3539 if (retval) 3540 return retval; 3541 } 3542 3543 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); 3544 if (IS_ERR(old.bh)) 3545 return PTR_ERR(old.bh); 3546 /* 3547 * Check for inode number is _not_ due to possible IO errors. 3548 * We might rmdir the source, keep it as pwd of some process 3549 * and merrily kill the link to whatever was created under the 3550 * same name. Goodbye sticky bit ;-< 3551 */ 3552 retval = -ENOENT; 3553 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3554 goto end_rename; 3555 3556 if ((old.dir != new.dir) && 3557 ext4_encrypted_inode(new.dir) && 3558 !fscrypt_has_permitted_context(new.dir, old.inode)) { 3559 retval = -EPERM; 3560 goto end_rename; 3561 } 3562 3563 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3564 &new.de, &new.inlined); 3565 if (IS_ERR(new.bh)) { 3566 retval = PTR_ERR(new.bh); 3567 new.bh = NULL; 3568 goto end_rename; 3569 } 3570 if (new.bh) { 3571 if (!new.inode) { 3572 brelse(new.bh); 3573 new.bh = NULL; 3574 } 3575 } 3576 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) 3577 ext4_alloc_da_blocks(old.inode); 3578 3579 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3580 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); 3581 if (!(flags & RENAME_WHITEOUT)) { 3582 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); 3583 if (IS_ERR(handle)) { 3584 retval = PTR_ERR(handle); 3585 handle = NULL; 3586 goto end_rename; 3587 } 3588 } else { 3589 whiteout = ext4_whiteout_for_rename(&old, credits, &handle); 3590 if (IS_ERR(whiteout)) { 3591 retval = PTR_ERR(whiteout); 3592 whiteout = NULL; 3593 goto end_rename; 3594 } 3595 } 3596 3597 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3598 ext4_handle_sync(handle); 3599 3600 if (S_ISDIR(old.inode->i_mode)) { 3601 if (new.inode) { 3602 retval = -ENOTEMPTY; 3603 if (!ext4_empty_dir(new.inode)) 3604 goto end_rename; 3605 } else { 3606 retval = -EMLINK; 3607 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) 3608 goto end_rename; 3609 } 3610 retval = ext4_rename_dir_prepare(handle, &old); 3611 if (retval) 3612 goto end_rename; 3613 } 3614 /* 3615 * If we're renaming a file within an inline_data dir and adding or 3616 * setting the new dirent causes a conversion from inline_data to 3617 * extents/blockmap, we need to force the dirent delete code to 3618 * re-read the directory, or else we end up trying to delete a dirent 3619 * from what is now the extent tree root (or a block map). 3620 */ 3621 force_reread = (new.dir->i_ino == old.dir->i_ino && 3622 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); 3623 3624 old_file_type = old.de->file_type; 3625 if (whiteout) { 3626 /* 3627 * Do this before adding a new entry, so the old entry is sure 3628 * to be still pointing to the valid old entry. 3629 */ 3630 retval = ext4_setent(handle, &old, whiteout->i_ino, 3631 EXT4_FT_CHRDEV); 3632 if (retval) 3633 goto end_rename; 3634 ext4_mark_inode_dirty(handle, whiteout); 3635 } 3636 if (!new.bh) { 3637 retval = ext4_add_entry(handle, new.dentry, old.inode); 3638 if (retval) 3639 goto end_rename; 3640 } else { 3641 retval = ext4_setent(handle, &new, 3642 old.inode->i_ino, old_file_type); 3643 if (retval) 3644 goto end_rename; 3645 } 3646 if (force_reread) 3647 force_reread = !ext4_test_inode_flag(new.dir, 3648 EXT4_INODE_INLINE_DATA); 3649 3650 /* 3651 * Like most other Unix systems, set the ctime for inodes on a 3652 * rename. 3653 */ 3654 old.inode->i_ctime = ext4_current_time(old.inode); 3655 ext4_mark_inode_dirty(handle, old.inode); 3656 3657 if (!whiteout) { 3658 /* 3659 * ok, that's it 3660 */ 3661 ext4_rename_delete(handle, &old, force_reread); 3662 } 3663 3664 if (new.inode) { 3665 ext4_dec_count(handle, new.inode); 3666 new.inode->i_ctime = ext4_current_time(new.inode); 3667 } 3668 old.dir->i_ctime = old.dir->i_mtime = ext4_current_time(old.dir); 3669 ext4_update_dx_flag(old.dir); 3670 if (old.dir_bh) { 3671 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3672 if (retval) 3673 goto end_rename; 3674 3675 ext4_dec_count(handle, old.dir); 3676 if (new.inode) { 3677 /* checked ext4_empty_dir above, can't have another 3678 * parent, ext4_dec_count() won't work for many-linked 3679 * dirs */ 3680 clear_nlink(new.inode); 3681 } else { 3682 ext4_inc_count(handle, new.dir); 3683 ext4_update_dx_flag(new.dir); 3684 ext4_mark_inode_dirty(handle, new.dir); 3685 } 3686 } 3687 ext4_mark_inode_dirty(handle, old.dir); 3688 if (new.inode) { 3689 ext4_mark_inode_dirty(handle, new.inode); 3690 if (!new.inode->i_nlink) 3691 ext4_orphan_add(handle, new.inode); 3692 } 3693 retval = 0; 3694 3695 end_rename: 3696 brelse(old.dir_bh); 3697 brelse(old.bh); 3698 brelse(new.bh); 3699 if (whiteout) { 3700 if (retval) 3701 drop_nlink(whiteout); 3702 unlock_new_inode(whiteout); 3703 iput(whiteout); 3704 } 3705 if (handle) 3706 ext4_journal_stop(handle); 3707 return retval; 3708 } 3709 3710 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, 3711 struct inode *new_dir, struct dentry *new_dentry) 3712 { 3713 handle_t *handle = NULL; 3714 struct ext4_renament old = { 3715 .dir = old_dir, 3716 .dentry = old_dentry, 3717 .inode = d_inode(old_dentry), 3718 }; 3719 struct ext4_renament new = { 3720 .dir = new_dir, 3721 .dentry = new_dentry, 3722 .inode = d_inode(new_dentry), 3723 }; 3724 u8 new_file_type; 3725 int retval; 3726 3727 if ((ext4_encrypted_inode(old_dir) || 3728 ext4_encrypted_inode(new_dir)) && 3729 (old_dir != new_dir) && 3730 (!fscrypt_has_permitted_context(new_dir, old.inode) || 3731 !fscrypt_has_permitted_context(old_dir, new.inode))) 3732 return -EPERM; 3733 3734 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) && 3735 !projid_eq(EXT4_I(new_dir)->i_projid, 3736 EXT4_I(old_dentry->d_inode)->i_projid)) || 3737 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) && 3738 !projid_eq(EXT4_I(old_dir)->i_projid, 3739 EXT4_I(new_dentry->d_inode)->i_projid))) 3740 return -EXDEV; 3741 3742 retval = dquot_initialize(old.dir); 3743 if (retval) 3744 return retval; 3745 retval = dquot_initialize(new.dir); 3746 if (retval) 3747 return retval; 3748 3749 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, 3750 &old.de, &old.inlined); 3751 if (IS_ERR(old.bh)) 3752 return PTR_ERR(old.bh); 3753 /* 3754 * Check for inode number is _not_ due to possible IO errors. 3755 * We might rmdir the source, keep it as pwd of some process 3756 * and merrily kill the link to whatever was created under the 3757 * same name. Goodbye sticky bit ;-< 3758 */ 3759 retval = -ENOENT; 3760 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3761 goto end_rename; 3762 3763 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3764 &new.de, &new.inlined); 3765 if (IS_ERR(new.bh)) { 3766 retval = PTR_ERR(new.bh); 3767 new.bh = NULL; 3768 goto end_rename; 3769 } 3770 3771 /* RENAME_EXCHANGE case: old *and* new must both exist */ 3772 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) 3773 goto end_rename; 3774 3775 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, 3776 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3777 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); 3778 if (IS_ERR(handle)) { 3779 retval = PTR_ERR(handle); 3780 handle = NULL; 3781 goto end_rename; 3782 } 3783 3784 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3785 ext4_handle_sync(handle); 3786 3787 if (S_ISDIR(old.inode->i_mode)) { 3788 old.is_dir = true; 3789 retval = ext4_rename_dir_prepare(handle, &old); 3790 if (retval) 3791 goto end_rename; 3792 } 3793 if (S_ISDIR(new.inode->i_mode)) { 3794 new.is_dir = true; 3795 retval = ext4_rename_dir_prepare(handle, &new); 3796 if (retval) 3797 goto end_rename; 3798 } 3799 3800 /* 3801 * Other than the special case of overwriting a directory, parents' 3802 * nlink only needs to be modified if this is a cross directory rename. 3803 */ 3804 if (old.dir != new.dir && old.is_dir != new.is_dir) { 3805 old.dir_nlink_delta = old.is_dir ? -1 : 1; 3806 new.dir_nlink_delta = -old.dir_nlink_delta; 3807 retval = -EMLINK; 3808 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || 3809 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) 3810 goto end_rename; 3811 } 3812 3813 new_file_type = new.de->file_type; 3814 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); 3815 if (retval) 3816 goto end_rename; 3817 3818 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); 3819 if (retval) 3820 goto end_rename; 3821 3822 /* 3823 * Like most other Unix systems, set the ctime for inodes on a 3824 * rename. 3825 */ 3826 old.inode->i_ctime = ext4_current_time(old.inode); 3827 new.inode->i_ctime = ext4_current_time(new.inode); 3828 ext4_mark_inode_dirty(handle, old.inode); 3829 ext4_mark_inode_dirty(handle, new.inode); 3830 3831 if (old.dir_bh) { 3832 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3833 if (retval) 3834 goto end_rename; 3835 } 3836 if (new.dir_bh) { 3837 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); 3838 if (retval) 3839 goto end_rename; 3840 } 3841 ext4_update_dir_count(handle, &old); 3842 ext4_update_dir_count(handle, &new); 3843 retval = 0; 3844 3845 end_rename: 3846 brelse(old.dir_bh); 3847 brelse(new.dir_bh); 3848 brelse(old.bh); 3849 brelse(new.bh); 3850 if (handle) 3851 ext4_journal_stop(handle); 3852 return retval; 3853 } 3854 3855 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, 3856 struct inode *new_dir, struct dentry *new_dentry, 3857 unsigned int flags) 3858 { 3859 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 3860 return -EINVAL; 3861 3862 if (flags & RENAME_EXCHANGE) { 3863 return ext4_cross_rename(old_dir, old_dentry, 3864 new_dir, new_dentry); 3865 } 3866 3867 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 3868 } 3869 3870 /* 3871 * directories can handle most operations... 3872 */ 3873 const struct inode_operations ext4_dir_inode_operations = { 3874 .create = ext4_create, 3875 .lookup = ext4_lookup, 3876 .link = ext4_link, 3877 .unlink = ext4_unlink, 3878 .symlink = ext4_symlink, 3879 .mkdir = ext4_mkdir, 3880 .rmdir = ext4_rmdir, 3881 .mknod = ext4_mknod, 3882 .tmpfile = ext4_tmpfile, 3883 .rename2 = ext4_rename2, 3884 .setattr = ext4_setattr, 3885 .setxattr = generic_setxattr, 3886 .getxattr = generic_getxattr, 3887 .listxattr = ext4_listxattr, 3888 .removexattr = generic_removexattr, 3889 .get_acl = ext4_get_acl, 3890 .set_acl = ext4_set_acl, 3891 .fiemap = ext4_fiemap, 3892 }; 3893 3894 const struct inode_operations ext4_special_inode_operations = { 3895 .setattr = ext4_setattr, 3896 .setxattr = generic_setxattr, 3897 .getxattr = generic_getxattr, 3898 .listxattr = ext4_listxattr, 3899 .removexattr = generic_removexattr, 3900 .get_acl = ext4_get_acl, 3901 .set_acl = ext4_set_acl, 3902 }; 3903