1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/ext4/namei.c 4 * 5 * Copyright (C) 1992, 1993, 1994, 1995 6 * Remy Card (card@masi.ibp.fr) 7 * Laboratoire MASI - Institut Blaise Pascal 8 * Universite Pierre et Marie Curie (Paris VI) 9 * 10 * from 11 * 12 * linux/fs/minix/namei.c 13 * 14 * Copyright (C) 1991, 1992 Linus Torvalds 15 * 16 * Big-endian to little-endian byte-swapping/bitmaps by 17 * David S. Miller (davem@caip.rutgers.edu), 1995 18 * Directory entry file type support and forward compatibility hooks 19 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998 20 * Hash Tree Directory indexing (c) 21 * Daniel Phillips, 2001 22 * Hash Tree Directory indexing porting 23 * Christopher Li, 2002 24 * Hash Tree Directory indexing cleanup 25 * Theodore Ts'o, 2002 26 */ 27 28 #include <linux/fs.h> 29 #include <linux/pagemap.h> 30 #include <linux/time.h> 31 #include <linux/fcntl.h> 32 #include <linux/stat.h> 33 #include <linux/string.h> 34 #include <linux/quotaops.h> 35 #include <linux/buffer_head.h> 36 #include <linux/bio.h> 37 #include "ext4.h" 38 #include "ext4_jbd2.h" 39 40 #include "xattr.h" 41 #include "acl.h" 42 43 #include <trace/events/ext4.h> 44 /* 45 * define how far ahead to read directories while searching them. 46 */ 47 #define NAMEI_RA_CHUNKS 2 48 #define NAMEI_RA_BLOCKS 4 49 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) 50 51 static struct buffer_head *ext4_append(handle_t *handle, 52 struct inode *inode, 53 ext4_lblk_t *block) 54 { 55 struct buffer_head *bh; 56 int err; 57 58 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb && 59 ((inode->i_size >> 10) >= 60 EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) 61 return ERR_PTR(-ENOSPC); 62 63 *block = inode->i_size >> inode->i_sb->s_blocksize_bits; 64 65 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE); 66 if (IS_ERR(bh)) 67 return bh; 68 inode->i_size += inode->i_sb->s_blocksize; 69 EXT4_I(inode)->i_disksize = inode->i_size; 70 BUFFER_TRACE(bh, "get_write_access"); 71 err = ext4_journal_get_write_access(handle, bh); 72 if (err) { 73 brelse(bh); 74 ext4_std_error(inode->i_sb, err); 75 return ERR_PTR(err); 76 } 77 return bh; 78 } 79 80 static int ext4_dx_csum_verify(struct inode *inode, 81 struct ext4_dir_entry *dirent); 82 83 typedef enum { 84 EITHER, INDEX, DIRENT 85 } dirblock_type_t; 86 87 #define ext4_read_dirblock(inode, block, type) \ 88 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__) 89 90 static struct buffer_head *__ext4_read_dirblock(struct inode *inode, 91 ext4_lblk_t block, 92 dirblock_type_t type, 93 const char *func, 94 unsigned int line) 95 { 96 struct buffer_head *bh; 97 struct ext4_dir_entry *dirent; 98 int is_dx_block = 0; 99 100 bh = ext4_bread(NULL, inode, block, 0); 101 if (IS_ERR(bh)) { 102 __ext4_warning(inode->i_sb, func, line, 103 "inode #%lu: lblock %lu: comm %s: " 104 "error %ld reading directory block", 105 inode->i_ino, (unsigned long)block, 106 current->comm, PTR_ERR(bh)); 107 108 return bh; 109 } 110 if (!bh) { 111 ext4_error_inode(inode, func, line, block, 112 "Directory hole found"); 113 return ERR_PTR(-EFSCORRUPTED); 114 } 115 dirent = (struct ext4_dir_entry *) bh->b_data; 116 /* Determine whether or not we have an index block */ 117 if (is_dx(inode)) { 118 if (block == 0) 119 is_dx_block = 1; 120 else if (ext4_rec_len_from_disk(dirent->rec_len, 121 inode->i_sb->s_blocksize) == 122 inode->i_sb->s_blocksize) 123 is_dx_block = 1; 124 } 125 if (!is_dx_block && type == INDEX) { 126 ext4_error_inode(inode, func, line, block, 127 "directory leaf block found instead of index block"); 128 return ERR_PTR(-EFSCORRUPTED); 129 } 130 if (!ext4_has_metadata_csum(inode->i_sb) || 131 buffer_verified(bh)) 132 return bh; 133 134 /* 135 * An empty leaf block can get mistaken for a index block; for 136 * this reason, we can only check the index checksum when the 137 * caller is sure it should be an index block. 138 */ 139 if (is_dx_block && type == INDEX) { 140 if (ext4_dx_csum_verify(inode, dirent)) 141 set_buffer_verified(bh); 142 else { 143 ext4_error_inode(inode, func, line, block, 144 "Directory index failed checksum"); 145 brelse(bh); 146 return ERR_PTR(-EFSBADCRC); 147 } 148 } 149 if (!is_dx_block) { 150 if (ext4_dirent_csum_verify(inode, dirent)) 151 set_buffer_verified(bh); 152 else { 153 ext4_error_inode(inode, func, line, block, 154 "Directory block failed checksum"); 155 brelse(bh); 156 return ERR_PTR(-EFSBADCRC); 157 } 158 } 159 return bh; 160 } 161 162 #ifndef assert 163 #define assert(test) J_ASSERT(test) 164 #endif 165 166 #ifdef DX_DEBUG 167 #define dxtrace(command) command 168 #else 169 #define dxtrace(command) 170 #endif 171 172 struct fake_dirent 173 { 174 __le32 inode; 175 __le16 rec_len; 176 u8 name_len; 177 u8 file_type; 178 }; 179 180 struct dx_countlimit 181 { 182 __le16 limit; 183 __le16 count; 184 }; 185 186 struct dx_entry 187 { 188 __le32 hash; 189 __le32 block; 190 }; 191 192 /* 193 * dx_root_info is laid out so that if it should somehow get overlaid by a 194 * dirent the two low bits of the hash version will be zero. Therefore, the 195 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 196 */ 197 198 struct dx_root 199 { 200 struct fake_dirent dot; 201 char dot_name[4]; 202 struct fake_dirent dotdot; 203 char dotdot_name[4]; 204 struct dx_root_info 205 { 206 __le32 reserved_zero; 207 u8 hash_version; 208 u8 info_length; /* 8 */ 209 u8 indirect_levels; 210 u8 unused_flags; 211 } 212 info; 213 struct dx_entry entries[0]; 214 }; 215 216 struct dx_node 217 { 218 struct fake_dirent fake; 219 struct dx_entry entries[0]; 220 }; 221 222 223 struct dx_frame 224 { 225 struct buffer_head *bh; 226 struct dx_entry *entries; 227 struct dx_entry *at; 228 }; 229 230 struct dx_map_entry 231 { 232 u32 hash; 233 u16 offs; 234 u16 size; 235 }; 236 237 /* 238 * This goes at the end of each htree block. 239 */ 240 struct dx_tail { 241 u32 dt_reserved; 242 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */ 243 }; 244 245 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry); 246 static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value); 247 static inline unsigned dx_get_hash(struct dx_entry *entry); 248 static void dx_set_hash(struct dx_entry *entry, unsigned value); 249 static unsigned dx_get_count(struct dx_entry *entries); 250 static unsigned dx_get_limit(struct dx_entry *entries); 251 static void dx_set_count(struct dx_entry *entries, unsigned value); 252 static void dx_set_limit(struct dx_entry *entries, unsigned value); 253 static unsigned dx_root_limit(struct inode *dir, unsigned infosize); 254 static unsigned dx_node_limit(struct inode *dir); 255 static struct dx_frame *dx_probe(struct ext4_filename *fname, 256 struct inode *dir, 257 struct dx_hash_info *hinfo, 258 struct dx_frame *frame); 259 static void dx_release(struct dx_frame *frames); 260 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 261 unsigned blocksize, struct dx_hash_info *hinfo, 262 struct dx_map_entry map[]); 263 static void dx_sort_map(struct dx_map_entry *map, unsigned count); 264 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to, 265 struct dx_map_entry *offsets, int count, unsigned blocksize); 266 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize); 267 static void dx_insert_block(struct dx_frame *frame, 268 u32 hash, ext4_lblk_t block); 269 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 270 struct dx_frame *frame, 271 struct dx_frame *frames, 272 __u32 *start_hash); 273 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 274 struct ext4_filename *fname, 275 struct ext4_dir_entry_2 **res_dir); 276 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 277 struct inode *dir, struct inode *inode); 278 279 /* checksumming functions */ 280 void initialize_dirent_tail(struct ext4_dir_entry_tail *t, 281 unsigned int blocksize) 282 { 283 memset(t, 0, sizeof(struct ext4_dir_entry_tail)); 284 t->det_rec_len = ext4_rec_len_to_disk( 285 sizeof(struct ext4_dir_entry_tail), blocksize); 286 t->det_reserved_ft = EXT4_FT_DIR_CSUM; 287 } 288 289 /* Walk through a dirent block to find a checksum "dirent" at the tail */ 290 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode, 291 struct ext4_dir_entry *de) 292 { 293 struct ext4_dir_entry_tail *t; 294 295 #ifdef PARANOID 296 struct ext4_dir_entry *d, *top; 297 298 d = de; 299 top = (struct ext4_dir_entry *)(((void *)de) + 300 (EXT4_BLOCK_SIZE(inode->i_sb) - 301 sizeof(struct ext4_dir_entry_tail))); 302 while (d < top && d->rec_len) 303 d = (struct ext4_dir_entry *)(((void *)d) + 304 le16_to_cpu(d->rec_len)); 305 306 if (d != top) 307 return NULL; 308 309 t = (struct ext4_dir_entry_tail *)d; 310 #else 311 t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb)); 312 #endif 313 314 if (t->det_reserved_zero1 || 315 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) || 316 t->det_reserved_zero2 || 317 t->det_reserved_ft != EXT4_FT_DIR_CSUM) 318 return NULL; 319 320 return t; 321 } 322 323 static __le32 ext4_dirent_csum(struct inode *inode, 324 struct ext4_dir_entry *dirent, int size) 325 { 326 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 327 struct ext4_inode_info *ei = EXT4_I(inode); 328 __u32 csum; 329 330 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 331 return cpu_to_le32(csum); 332 } 333 334 #define warn_no_space_for_csum(inode) \ 335 __warn_no_space_for_csum((inode), __func__, __LINE__) 336 337 static void __warn_no_space_for_csum(struct inode *inode, const char *func, 338 unsigned int line) 339 { 340 __ext4_warning_inode(inode, func, line, 341 "No space for directory leaf checksum. Please run e2fsck -D."); 342 } 343 344 int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent) 345 { 346 struct ext4_dir_entry_tail *t; 347 348 if (!ext4_has_metadata_csum(inode->i_sb)) 349 return 1; 350 351 t = get_dirent_tail(inode, dirent); 352 if (!t) { 353 warn_no_space_for_csum(inode); 354 return 0; 355 } 356 357 if (t->det_checksum != ext4_dirent_csum(inode, dirent, 358 (void *)t - (void *)dirent)) 359 return 0; 360 361 return 1; 362 } 363 364 static void ext4_dirent_csum_set(struct inode *inode, 365 struct ext4_dir_entry *dirent) 366 { 367 struct ext4_dir_entry_tail *t; 368 369 if (!ext4_has_metadata_csum(inode->i_sb)) 370 return; 371 372 t = get_dirent_tail(inode, dirent); 373 if (!t) { 374 warn_no_space_for_csum(inode); 375 return; 376 } 377 378 t->det_checksum = ext4_dirent_csum(inode, dirent, 379 (void *)t - (void *)dirent); 380 } 381 382 int ext4_handle_dirty_dirent_node(handle_t *handle, 383 struct inode *inode, 384 struct buffer_head *bh) 385 { 386 ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 387 return ext4_handle_dirty_metadata(handle, inode, bh); 388 } 389 390 static struct dx_countlimit *get_dx_countlimit(struct inode *inode, 391 struct ext4_dir_entry *dirent, 392 int *offset) 393 { 394 struct ext4_dir_entry *dp; 395 struct dx_root_info *root; 396 int count_offset; 397 398 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb)) 399 count_offset = 8; 400 else if (le16_to_cpu(dirent->rec_len) == 12) { 401 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12); 402 if (le16_to_cpu(dp->rec_len) != 403 EXT4_BLOCK_SIZE(inode->i_sb) - 12) 404 return NULL; 405 root = (struct dx_root_info *)(((void *)dp + 12)); 406 if (root->reserved_zero || 407 root->info_length != sizeof(struct dx_root_info)) 408 return NULL; 409 count_offset = 32; 410 } else 411 return NULL; 412 413 if (offset) 414 *offset = count_offset; 415 return (struct dx_countlimit *)(((void *)dirent) + count_offset); 416 } 417 418 static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent, 419 int count_offset, int count, struct dx_tail *t) 420 { 421 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 422 struct ext4_inode_info *ei = EXT4_I(inode); 423 __u32 csum; 424 int size; 425 __u32 dummy_csum = 0; 426 int offset = offsetof(struct dx_tail, dt_checksum); 427 428 size = count_offset + (count * sizeof(struct dx_entry)); 429 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 430 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset); 431 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); 432 433 return cpu_to_le32(csum); 434 } 435 436 static int ext4_dx_csum_verify(struct inode *inode, 437 struct ext4_dir_entry *dirent) 438 { 439 struct dx_countlimit *c; 440 struct dx_tail *t; 441 int count_offset, limit, count; 442 443 if (!ext4_has_metadata_csum(inode->i_sb)) 444 return 1; 445 446 c = get_dx_countlimit(inode, dirent, &count_offset); 447 if (!c) { 448 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 449 return 0; 450 } 451 limit = le16_to_cpu(c->limit); 452 count = le16_to_cpu(c->count); 453 if (count_offset + (limit * sizeof(struct dx_entry)) > 454 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 455 warn_no_space_for_csum(inode); 456 return 0; 457 } 458 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 459 460 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset, 461 count, t)) 462 return 0; 463 return 1; 464 } 465 466 static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent) 467 { 468 struct dx_countlimit *c; 469 struct dx_tail *t; 470 int count_offset, limit, count; 471 472 if (!ext4_has_metadata_csum(inode->i_sb)) 473 return; 474 475 c = get_dx_countlimit(inode, dirent, &count_offset); 476 if (!c) { 477 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 478 return; 479 } 480 limit = le16_to_cpu(c->limit); 481 count = le16_to_cpu(c->count); 482 if (count_offset + (limit * sizeof(struct dx_entry)) > 483 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 484 warn_no_space_for_csum(inode); 485 return; 486 } 487 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 488 489 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t); 490 } 491 492 static inline int ext4_handle_dirty_dx_node(handle_t *handle, 493 struct inode *inode, 494 struct buffer_head *bh) 495 { 496 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 497 return ext4_handle_dirty_metadata(handle, inode, bh); 498 } 499 500 /* 501 * p is at least 6 bytes before the end of page 502 */ 503 static inline struct ext4_dir_entry_2 * 504 ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize) 505 { 506 return (struct ext4_dir_entry_2 *)((char *)p + 507 ext4_rec_len_from_disk(p->rec_len, blocksize)); 508 } 509 510 /* 511 * Future: use high four bits of block for coalesce-on-delete flags 512 * Mask them off for now. 513 */ 514 515 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry) 516 { 517 return le32_to_cpu(entry->block) & 0x0fffffff; 518 } 519 520 static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value) 521 { 522 entry->block = cpu_to_le32(value); 523 } 524 525 static inline unsigned dx_get_hash(struct dx_entry *entry) 526 { 527 return le32_to_cpu(entry->hash); 528 } 529 530 static inline void dx_set_hash(struct dx_entry *entry, unsigned value) 531 { 532 entry->hash = cpu_to_le32(value); 533 } 534 535 static inline unsigned dx_get_count(struct dx_entry *entries) 536 { 537 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 538 } 539 540 static inline unsigned dx_get_limit(struct dx_entry *entries) 541 { 542 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 543 } 544 545 static inline void dx_set_count(struct dx_entry *entries, unsigned value) 546 { 547 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 548 } 549 550 static inline void dx_set_limit(struct dx_entry *entries, unsigned value) 551 { 552 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 553 } 554 555 static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize) 556 { 557 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) - 558 EXT4_DIR_REC_LEN(2) - infosize; 559 560 if (ext4_has_metadata_csum(dir->i_sb)) 561 entry_space -= sizeof(struct dx_tail); 562 return entry_space / sizeof(struct dx_entry); 563 } 564 565 static inline unsigned dx_node_limit(struct inode *dir) 566 { 567 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0); 568 569 if (ext4_has_metadata_csum(dir->i_sb)) 570 entry_space -= sizeof(struct dx_tail); 571 return entry_space / sizeof(struct dx_entry); 572 } 573 574 /* 575 * Debug 576 */ 577 #ifdef DX_DEBUG 578 static void dx_show_index(char * label, struct dx_entry *entries) 579 { 580 int i, n = dx_get_count (entries); 581 printk(KERN_DEBUG "%s index", label); 582 for (i = 0; i < n; i++) { 583 printk(KERN_CONT " %x->%lu", 584 i ? dx_get_hash(entries + i) : 0, 585 (unsigned long)dx_get_block(entries + i)); 586 } 587 printk(KERN_CONT "\n"); 588 } 589 590 struct stats 591 { 592 unsigned names; 593 unsigned space; 594 unsigned bcount; 595 }; 596 597 static struct stats dx_show_leaf(struct inode *dir, 598 struct dx_hash_info *hinfo, 599 struct ext4_dir_entry_2 *de, 600 int size, int show_names) 601 { 602 unsigned names = 0, space = 0; 603 char *base = (char *) de; 604 struct dx_hash_info h = *hinfo; 605 606 printk("names: "); 607 while ((char *) de < base + size) 608 { 609 if (de->inode) 610 { 611 if (show_names) 612 { 613 #ifdef CONFIG_EXT4_FS_ENCRYPTION 614 int len; 615 char *name; 616 struct fscrypt_str fname_crypto_str = 617 FSTR_INIT(NULL, 0); 618 int res = 0; 619 620 name = de->name; 621 len = de->name_len; 622 if (ext4_encrypted_inode(dir)) 623 res = fscrypt_get_encryption_info(dir); 624 if (res) { 625 printk(KERN_WARNING "Error setting up" 626 " fname crypto: %d\n", res); 627 } 628 if (!fscrypt_has_encryption_key(dir)) { 629 /* Directory is not encrypted */ 630 ext4fs_dirhash(de->name, 631 de->name_len, &h); 632 printk("%*.s:(U)%x.%u ", len, 633 name, h.hash, 634 (unsigned) ((char *) de 635 - base)); 636 } else { 637 struct fscrypt_str de_name = 638 FSTR_INIT(name, len); 639 640 /* Directory is encrypted */ 641 res = fscrypt_fname_alloc_buffer( 642 dir, len, 643 &fname_crypto_str); 644 if (res) 645 printk(KERN_WARNING "Error " 646 "allocating crypto " 647 "buffer--skipping " 648 "crypto\n"); 649 res = fscrypt_fname_disk_to_usr(dir, 650 0, 0, &de_name, 651 &fname_crypto_str); 652 if (res) { 653 printk(KERN_WARNING "Error " 654 "converting filename " 655 "from disk to usr" 656 "\n"); 657 name = "??"; 658 len = 2; 659 } else { 660 name = fname_crypto_str.name; 661 len = fname_crypto_str.len; 662 } 663 ext4fs_dirhash(de->name, de->name_len, 664 &h); 665 printk("%*.s:(E)%x.%u ", len, name, 666 h.hash, (unsigned) ((char *) de 667 - base)); 668 fscrypt_fname_free_buffer( 669 &fname_crypto_str); 670 } 671 #else 672 int len = de->name_len; 673 char *name = de->name; 674 ext4fs_dirhash(de->name, de->name_len, &h); 675 printk("%*.s:%x.%u ", len, name, h.hash, 676 (unsigned) ((char *) de - base)); 677 #endif 678 } 679 space += EXT4_DIR_REC_LEN(de->name_len); 680 names++; 681 } 682 de = ext4_next_entry(de, size); 683 } 684 printk(KERN_CONT "(%i)\n", names); 685 return (struct stats) { names, space, 1 }; 686 } 687 688 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 689 struct dx_entry *entries, int levels) 690 { 691 unsigned blocksize = dir->i_sb->s_blocksize; 692 unsigned count = dx_get_count(entries), names = 0, space = 0, i; 693 unsigned bcount = 0; 694 struct buffer_head *bh; 695 printk("%i indexed blocks...\n", count); 696 for (i = 0; i < count; i++, entries++) 697 { 698 ext4_lblk_t block = dx_get_block(entries); 699 ext4_lblk_t hash = i ? dx_get_hash(entries): 0; 700 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 701 struct stats stats; 702 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 703 bh = ext4_bread(NULL,dir, block, 0); 704 if (!bh || IS_ERR(bh)) 705 continue; 706 stats = levels? 707 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 708 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) 709 bh->b_data, blocksize, 0); 710 names += stats.names; 711 space += stats.space; 712 bcount += stats.bcount; 713 brelse(bh); 714 } 715 if (bcount) 716 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n", 717 levels ? "" : " ", names, space/bcount, 718 (space/bcount)*100/blocksize); 719 return (struct stats) { names, space, bcount}; 720 } 721 #endif /* DX_DEBUG */ 722 723 /* 724 * Probe for a directory leaf block to search. 725 * 726 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 727 * error in the directory index, and the caller should fall back to 728 * searching the directory normally. The callers of dx_probe **MUST** 729 * check for this error code, and make sure it never gets reflected 730 * back to userspace. 731 */ 732 static struct dx_frame * 733 dx_probe(struct ext4_filename *fname, struct inode *dir, 734 struct dx_hash_info *hinfo, struct dx_frame *frame_in) 735 { 736 unsigned count, indirect; 737 struct dx_entry *at, *entries, *p, *q, *m; 738 struct dx_root *root; 739 struct dx_frame *frame = frame_in; 740 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR); 741 u32 hash; 742 743 memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0])); 744 frame->bh = ext4_read_dirblock(dir, 0, INDEX); 745 if (IS_ERR(frame->bh)) 746 return (struct dx_frame *) frame->bh; 747 748 root = (struct dx_root *) frame->bh->b_data; 749 if (root->info.hash_version != DX_HASH_TEA && 750 root->info.hash_version != DX_HASH_HALF_MD4 && 751 root->info.hash_version != DX_HASH_LEGACY) { 752 ext4_warning_inode(dir, "Unrecognised inode hash code %u", 753 root->info.hash_version); 754 goto fail; 755 } 756 if (fname) 757 hinfo = &fname->hinfo; 758 hinfo->hash_version = root->info.hash_version; 759 if (hinfo->hash_version <= DX_HASH_TEA) 760 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 761 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; 762 if (fname && fname_name(fname)) 763 ext4fs_dirhash(fname_name(fname), fname_len(fname), hinfo); 764 hash = hinfo->hash; 765 766 if (root->info.unused_flags & 1) { 767 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x", 768 root->info.unused_flags); 769 goto fail; 770 } 771 772 indirect = root->info.indirect_levels; 773 if (indirect >= ext4_dir_htree_level(dir->i_sb)) { 774 ext4_warning(dir->i_sb, 775 "Directory (ino: %lu) htree depth %#06x exceed" 776 "supported value", dir->i_ino, 777 ext4_dir_htree_level(dir->i_sb)); 778 if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) { 779 ext4_warning(dir->i_sb, "Enable large directory " 780 "feature to access it"); 781 } 782 goto fail; 783 } 784 785 entries = (struct dx_entry *)(((char *)&root->info) + 786 root->info.info_length); 787 788 if (dx_get_limit(entries) != dx_root_limit(dir, 789 root->info.info_length)) { 790 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u", 791 dx_get_limit(entries), 792 dx_root_limit(dir, root->info.info_length)); 793 goto fail; 794 } 795 796 dxtrace(printk("Look up %x", hash)); 797 while (1) { 798 count = dx_get_count(entries); 799 if (!count || count > dx_get_limit(entries)) { 800 ext4_warning_inode(dir, 801 "dx entry: count %u beyond limit %u", 802 count, dx_get_limit(entries)); 803 goto fail; 804 } 805 806 p = entries + 1; 807 q = entries + count - 1; 808 while (p <= q) { 809 m = p + (q - p) / 2; 810 dxtrace(printk(KERN_CONT ".")); 811 if (dx_get_hash(m) > hash) 812 q = m - 1; 813 else 814 p = m + 1; 815 } 816 817 if (0) { // linear search cross check 818 unsigned n = count - 1; 819 at = entries; 820 while (n--) 821 { 822 dxtrace(printk(KERN_CONT ",")); 823 if (dx_get_hash(++at) > hash) 824 { 825 at--; 826 break; 827 } 828 } 829 assert (at == p - 1); 830 } 831 832 at = p - 1; 833 dxtrace(printk(KERN_CONT " %x->%u\n", 834 at == entries ? 0 : dx_get_hash(at), 835 dx_get_block(at))); 836 frame->entries = entries; 837 frame->at = at; 838 if (!indirect--) 839 return frame; 840 frame++; 841 frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX); 842 if (IS_ERR(frame->bh)) { 843 ret_err = (struct dx_frame *) frame->bh; 844 frame->bh = NULL; 845 goto fail; 846 } 847 entries = ((struct dx_node *) frame->bh->b_data)->entries; 848 849 if (dx_get_limit(entries) != dx_node_limit(dir)) { 850 ext4_warning_inode(dir, 851 "dx entry: limit %u != node limit %u", 852 dx_get_limit(entries), dx_node_limit(dir)); 853 goto fail; 854 } 855 } 856 fail: 857 while (frame >= frame_in) { 858 brelse(frame->bh); 859 frame--; 860 } 861 862 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR)) 863 ext4_warning_inode(dir, 864 "Corrupt directory, running e2fsck is recommended"); 865 return ret_err; 866 } 867 868 static void dx_release(struct dx_frame *frames) 869 { 870 struct dx_root_info *info; 871 int i; 872 873 if (frames[0].bh == NULL) 874 return; 875 876 info = &((struct dx_root *)frames[0].bh->b_data)->info; 877 for (i = 0; i <= info->indirect_levels; i++) { 878 if (frames[i].bh == NULL) 879 break; 880 brelse(frames[i].bh); 881 frames[i].bh = NULL; 882 } 883 } 884 885 /* 886 * This function increments the frame pointer to search the next leaf 887 * block, and reads in the necessary intervening nodes if the search 888 * should be necessary. Whether or not the search is necessary is 889 * controlled by the hash parameter. If the hash value is even, then 890 * the search is only continued if the next block starts with that 891 * hash value. This is used if we are searching for a specific file. 892 * 893 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 894 * 895 * This function returns 1 if the caller should continue to search, 896 * or 0 if it should not. If there is an error reading one of the 897 * index blocks, it will a negative error code. 898 * 899 * If start_hash is non-null, it will be filled in with the starting 900 * hash of the next page. 901 */ 902 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 903 struct dx_frame *frame, 904 struct dx_frame *frames, 905 __u32 *start_hash) 906 { 907 struct dx_frame *p; 908 struct buffer_head *bh; 909 int num_frames = 0; 910 __u32 bhash; 911 912 p = frame; 913 /* 914 * Find the next leaf page by incrementing the frame pointer. 915 * If we run out of entries in the interior node, loop around and 916 * increment pointer in the parent node. When we break out of 917 * this loop, num_frames indicates the number of interior 918 * nodes need to be read. 919 */ 920 while (1) { 921 if (++(p->at) < p->entries + dx_get_count(p->entries)) 922 break; 923 if (p == frames) 924 return 0; 925 num_frames++; 926 p--; 927 } 928 929 /* 930 * If the hash is 1, then continue only if the next page has a 931 * continuation hash of any value. This is used for readdir 932 * handling. Otherwise, check to see if the hash matches the 933 * desired contiuation hash. If it doesn't, return since 934 * there's no point to read in the successive index pages. 935 */ 936 bhash = dx_get_hash(p->at); 937 if (start_hash) 938 *start_hash = bhash; 939 if ((hash & 1) == 0) { 940 if ((bhash & ~1) != hash) 941 return 0; 942 } 943 /* 944 * If the hash is HASH_NB_ALWAYS, we always go to the next 945 * block so no check is necessary 946 */ 947 while (num_frames--) { 948 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX); 949 if (IS_ERR(bh)) 950 return PTR_ERR(bh); 951 p++; 952 brelse(p->bh); 953 p->bh = bh; 954 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 955 } 956 return 1; 957 } 958 959 960 /* 961 * This function fills a red-black tree with information from a 962 * directory block. It returns the number directory entries loaded 963 * into the tree. If there is an error it is returned in err. 964 */ 965 static int htree_dirblock_to_tree(struct file *dir_file, 966 struct inode *dir, ext4_lblk_t block, 967 struct dx_hash_info *hinfo, 968 __u32 start_hash, __u32 start_minor_hash) 969 { 970 struct buffer_head *bh; 971 struct ext4_dir_entry_2 *de, *top; 972 int err = 0, count = 0; 973 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str; 974 975 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", 976 (unsigned long)block)); 977 bh = ext4_read_dirblock(dir, block, DIRENT); 978 if (IS_ERR(bh)) 979 return PTR_ERR(bh); 980 981 de = (struct ext4_dir_entry_2 *) bh->b_data; 982 top = (struct ext4_dir_entry_2 *) ((char *) de + 983 dir->i_sb->s_blocksize - 984 EXT4_DIR_REC_LEN(0)); 985 #ifdef CONFIG_EXT4_FS_ENCRYPTION 986 /* Check if the directory is encrypted */ 987 if (ext4_encrypted_inode(dir)) { 988 err = fscrypt_get_encryption_info(dir); 989 if (err < 0) { 990 brelse(bh); 991 return err; 992 } 993 err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN, 994 &fname_crypto_str); 995 if (err < 0) { 996 brelse(bh); 997 return err; 998 } 999 } 1000 #endif 1001 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { 1002 if (ext4_check_dir_entry(dir, NULL, de, bh, 1003 bh->b_data, bh->b_size, 1004 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb)) 1005 + ((char *)de - bh->b_data))) { 1006 /* silently ignore the rest of the block */ 1007 break; 1008 } 1009 ext4fs_dirhash(de->name, de->name_len, hinfo); 1010 if ((hinfo->hash < start_hash) || 1011 ((hinfo->hash == start_hash) && 1012 (hinfo->minor_hash < start_minor_hash))) 1013 continue; 1014 if (de->inode == 0) 1015 continue; 1016 if (!ext4_encrypted_inode(dir)) { 1017 tmp_str.name = de->name; 1018 tmp_str.len = de->name_len; 1019 err = ext4_htree_store_dirent(dir_file, 1020 hinfo->hash, hinfo->minor_hash, de, 1021 &tmp_str); 1022 } else { 1023 int save_len = fname_crypto_str.len; 1024 struct fscrypt_str de_name = FSTR_INIT(de->name, 1025 de->name_len); 1026 1027 /* Directory is encrypted */ 1028 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash, 1029 hinfo->minor_hash, &de_name, 1030 &fname_crypto_str); 1031 if (err) { 1032 count = err; 1033 goto errout; 1034 } 1035 err = ext4_htree_store_dirent(dir_file, 1036 hinfo->hash, hinfo->minor_hash, de, 1037 &fname_crypto_str); 1038 fname_crypto_str.len = save_len; 1039 } 1040 if (err != 0) { 1041 count = err; 1042 goto errout; 1043 } 1044 count++; 1045 } 1046 errout: 1047 brelse(bh); 1048 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1049 fscrypt_fname_free_buffer(&fname_crypto_str); 1050 #endif 1051 return count; 1052 } 1053 1054 1055 /* 1056 * This function fills a red-black tree with information from a 1057 * directory. We start scanning the directory in hash order, starting 1058 * at start_hash and start_minor_hash. 1059 * 1060 * This function returns the number of entries inserted into the tree, 1061 * or a negative error code. 1062 */ 1063 int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, 1064 __u32 start_minor_hash, __u32 *next_hash) 1065 { 1066 struct dx_hash_info hinfo; 1067 struct ext4_dir_entry_2 *de; 1068 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1069 struct inode *dir; 1070 ext4_lblk_t block; 1071 int count = 0; 1072 int ret, err; 1073 __u32 hashval; 1074 struct fscrypt_str tmp_str; 1075 1076 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n", 1077 start_hash, start_minor_hash)); 1078 dir = file_inode(dir_file); 1079 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) { 1080 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1081 if (hinfo.hash_version <= DX_HASH_TEA) 1082 hinfo.hash_version += 1083 EXT4_SB(dir->i_sb)->s_hash_unsigned; 1084 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1085 if (ext4_has_inline_data(dir)) { 1086 int has_inline_data = 1; 1087 count = htree_inlinedir_to_tree(dir_file, dir, 0, 1088 &hinfo, start_hash, 1089 start_minor_hash, 1090 &has_inline_data); 1091 if (has_inline_data) { 1092 *next_hash = ~0; 1093 return count; 1094 } 1095 } 1096 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 1097 start_hash, start_minor_hash); 1098 *next_hash = ~0; 1099 return count; 1100 } 1101 hinfo.hash = start_hash; 1102 hinfo.minor_hash = 0; 1103 frame = dx_probe(NULL, dir, &hinfo, frames); 1104 if (IS_ERR(frame)) 1105 return PTR_ERR(frame); 1106 1107 /* Add '.' and '..' from the htree header */ 1108 if (!start_hash && !start_minor_hash) { 1109 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1110 tmp_str.name = de->name; 1111 tmp_str.len = de->name_len; 1112 err = ext4_htree_store_dirent(dir_file, 0, 0, 1113 de, &tmp_str); 1114 if (err != 0) 1115 goto errout; 1116 count++; 1117 } 1118 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 1119 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1120 de = ext4_next_entry(de, dir->i_sb->s_blocksize); 1121 tmp_str.name = de->name; 1122 tmp_str.len = de->name_len; 1123 err = ext4_htree_store_dirent(dir_file, 2, 0, 1124 de, &tmp_str); 1125 if (err != 0) 1126 goto errout; 1127 count++; 1128 } 1129 1130 while (1) { 1131 if (fatal_signal_pending(current)) { 1132 err = -ERESTARTSYS; 1133 goto errout; 1134 } 1135 cond_resched(); 1136 block = dx_get_block(frame->at); 1137 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 1138 start_hash, start_minor_hash); 1139 if (ret < 0) { 1140 err = ret; 1141 goto errout; 1142 } 1143 count += ret; 1144 hashval = ~0; 1145 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS, 1146 frame, frames, &hashval); 1147 *next_hash = hashval; 1148 if (ret < 0) { 1149 err = ret; 1150 goto errout; 1151 } 1152 /* 1153 * Stop if: (a) there are no more entries, or 1154 * (b) we have inserted at least one entry and the 1155 * next hash value is not a continuation 1156 */ 1157 if ((ret == 0) || 1158 (count && ((hashval & 1) == 0))) 1159 break; 1160 } 1161 dx_release(frames); 1162 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, " 1163 "next hash: %x\n", count, *next_hash)); 1164 return count; 1165 errout: 1166 dx_release(frames); 1167 return (err); 1168 } 1169 1170 static inline int search_dirblock(struct buffer_head *bh, 1171 struct inode *dir, 1172 struct ext4_filename *fname, 1173 unsigned int offset, 1174 struct ext4_dir_entry_2 **res_dir) 1175 { 1176 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir, 1177 fname, offset, res_dir); 1178 } 1179 1180 /* 1181 * Directory block splitting, compacting 1182 */ 1183 1184 /* 1185 * Create map of hash values, offsets, and sizes, stored at end of block. 1186 * Returns number of entries mapped. 1187 */ 1188 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 1189 unsigned blocksize, struct dx_hash_info *hinfo, 1190 struct dx_map_entry *map_tail) 1191 { 1192 int count = 0; 1193 char *base = (char *) de; 1194 struct dx_hash_info h = *hinfo; 1195 1196 while ((char *) de < base + blocksize) { 1197 if (de->name_len && de->inode) { 1198 ext4fs_dirhash(de->name, de->name_len, &h); 1199 map_tail--; 1200 map_tail->hash = h.hash; 1201 map_tail->offs = ((char *) de - base)>>2; 1202 map_tail->size = le16_to_cpu(de->rec_len); 1203 count++; 1204 cond_resched(); 1205 } 1206 /* XXX: do we need to check rec_len == 0 case? -Chris */ 1207 de = ext4_next_entry(de, blocksize); 1208 } 1209 return count; 1210 } 1211 1212 /* Sort map by hash value */ 1213 static void dx_sort_map (struct dx_map_entry *map, unsigned count) 1214 { 1215 struct dx_map_entry *p, *q, *top = map + count - 1; 1216 int more; 1217 /* Combsort until bubble sort doesn't suck */ 1218 while (count > 2) { 1219 count = count*10/13; 1220 if (count - 9 < 2) /* 9, 10 -> 11 */ 1221 count = 11; 1222 for (p = top, q = p - count; q >= map; p--, q--) 1223 if (p->hash < q->hash) 1224 swap(*p, *q); 1225 } 1226 /* Garden variety bubble sort */ 1227 do { 1228 more = 0; 1229 q = top; 1230 while (q-- > map) { 1231 if (q[1].hash >= q[0].hash) 1232 continue; 1233 swap(*(q+1), *q); 1234 more = 1; 1235 } 1236 } while(more); 1237 } 1238 1239 static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) 1240 { 1241 struct dx_entry *entries = frame->entries; 1242 struct dx_entry *old = frame->at, *new = old + 1; 1243 int count = dx_get_count(entries); 1244 1245 assert(count < dx_get_limit(entries)); 1246 assert(old < entries + count); 1247 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 1248 dx_set_hash(new, hash); 1249 dx_set_block(new, block); 1250 dx_set_count(entries, count + 1); 1251 } 1252 1253 /* 1254 * Test whether a directory entry matches the filename being searched for. 1255 * 1256 * Return: %true if the directory entry matches, otherwise %false. 1257 */ 1258 static inline bool ext4_match(const struct ext4_filename *fname, 1259 const struct ext4_dir_entry_2 *de) 1260 { 1261 struct fscrypt_name f; 1262 1263 if (!de->inode) 1264 return false; 1265 1266 f.usr_fname = fname->usr_fname; 1267 f.disk_name = fname->disk_name; 1268 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1269 f.crypto_buf = fname->crypto_buf; 1270 #endif 1271 return fscrypt_match_name(&f, de->name, de->name_len); 1272 } 1273 1274 /* 1275 * Returns 0 if not found, -1 on failure, and 1 on success 1276 */ 1277 int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, 1278 struct inode *dir, struct ext4_filename *fname, 1279 unsigned int offset, struct ext4_dir_entry_2 **res_dir) 1280 { 1281 struct ext4_dir_entry_2 * de; 1282 char * dlimit; 1283 int de_len; 1284 1285 de = (struct ext4_dir_entry_2 *)search_buf; 1286 dlimit = search_buf + buf_size; 1287 while ((char *) de < dlimit) { 1288 /* this code is executed quadratically often */ 1289 /* do minimal checking `by hand' */ 1290 if ((char *) de + de->name_len <= dlimit && 1291 ext4_match(fname, de)) { 1292 /* found a match - just to be sure, do 1293 * a full check */ 1294 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, 1295 bh->b_size, offset)) 1296 return -1; 1297 *res_dir = de; 1298 return 1; 1299 } 1300 /* prevent looping on a bad block */ 1301 de_len = ext4_rec_len_from_disk(de->rec_len, 1302 dir->i_sb->s_blocksize); 1303 if (de_len <= 0) 1304 return -1; 1305 offset += de_len; 1306 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); 1307 } 1308 return 0; 1309 } 1310 1311 static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block, 1312 struct ext4_dir_entry *de) 1313 { 1314 struct super_block *sb = dir->i_sb; 1315 1316 if (!is_dx(dir)) 1317 return 0; 1318 if (block == 0) 1319 return 1; 1320 if (de->inode == 0 && 1321 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) == 1322 sb->s_blocksize) 1323 return 1; 1324 return 0; 1325 } 1326 1327 /* 1328 * ext4_find_entry() 1329 * 1330 * finds an entry in the specified directory with the wanted name. It 1331 * returns the cache buffer in which the entry was found, and the entry 1332 * itself (as a parameter - res_dir). It does NOT read the inode of the 1333 * entry - you'll have to do that yourself if you want to. 1334 * 1335 * The returned buffer_head has ->b_count elevated. The caller is expected 1336 * to brelse() it when appropriate. 1337 */ 1338 static struct buffer_head * ext4_find_entry (struct inode *dir, 1339 const struct qstr *d_name, 1340 struct ext4_dir_entry_2 **res_dir, 1341 int *inlined) 1342 { 1343 struct super_block *sb; 1344 struct buffer_head *bh_use[NAMEI_RA_SIZE]; 1345 struct buffer_head *bh, *ret = NULL; 1346 ext4_lblk_t start, block; 1347 const u8 *name = d_name->name; 1348 size_t ra_max = 0; /* Number of bh's in the readahead 1349 buffer, bh_use[] */ 1350 size_t ra_ptr = 0; /* Current index into readahead 1351 buffer */ 1352 ext4_lblk_t nblocks; 1353 int i, namelen, retval; 1354 struct ext4_filename fname; 1355 1356 *res_dir = NULL; 1357 sb = dir->i_sb; 1358 namelen = d_name->len; 1359 if (namelen > EXT4_NAME_LEN) 1360 return NULL; 1361 1362 retval = ext4_fname_setup_filename(dir, d_name, 1, &fname); 1363 if (retval == -ENOENT) 1364 return NULL; 1365 if (retval) 1366 return ERR_PTR(retval); 1367 1368 if (ext4_has_inline_data(dir)) { 1369 int has_inline_data = 1; 1370 ret = ext4_find_inline_entry(dir, &fname, res_dir, 1371 &has_inline_data); 1372 if (has_inline_data) { 1373 if (inlined) 1374 *inlined = 1; 1375 goto cleanup_and_exit; 1376 } 1377 } 1378 1379 if ((namelen <= 2) && (name[0] == '.') && 1380 (name[1] == '.' || name[1] == '\0')) { 1381 /* 1382 * "." or ".." will only be in the first block 1383 * NFS may look up ".."; "." should be handled by the VFS 1384 */ 1385 block = start = 0; 1386 nblocks = 1; 1387 goto restart; 1388 } 1389 if (is_dx(dir)) { 1390 ret = ext4_dx_find_entry(dir, &fname, res_dir); 1391 /* 1392 * On success, or if the error was file not found, 1393 * return. Otherwise, fall back to doing a search the 1394 * old fashioned way. 1395 */ 1396 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) 1397 goto cleanup_and_exit; 1398 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " 1399 "falling back\n")); 1400 } 1401 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1402 start = EXT4_I(dir)->i_dir_start_lookup; 1403 if (start >= nblocks) 1404 start = 0; 1405 block = start; 1406 restart: 1407 do { 1408 /* 1409 * We deal with the read-ahead logic here. 1410 */ 1411 if (ra_ptr >= ra_max) { 1412 /* Refill the readahead buffer */ 1413 ra_ptr = 0; 1414 if (block < start) 1415 ra_max = start - block; 1416 else 1417 ra_max = nblocks - block; 1418 ra_max = min(ra_max, ARRAY_SIZE(bh_use)); 1419 retval = ext4_bread_batch(dir, block, ra_max, 1420 false /* wait */, bh_use); 1421 if (retval) { 1422 ret = ERR_PTR(retval); 1423 ra_max = 0; 1424 goto cleanup_and_exit; 1425 } 1426 } 1427 if ((bh = bh_use[ra_ptr++]) == NULL) 1428 goto next; 1429 wait_on_buffer(bh); 1430 if (!buffer_uptodate(bh)) { 1431 EXT4_ERROR_INODE(dir, "reading directory lblock %lu", 1432 (unsigned long) block); 1433 brelse(bh); 1434 ret = ERR_PTR(-EIO); 1435 goto cleanup_and_exit; 1436 } 1437 if (!buffer_verified(bh) && 1438 !is_dx_internal_node(dir, block, 1439 (struct ext4_dir_entry *)bh->b_data) && 1440 !ext4_dirent_csum_verify(dir, 1441 (struct ext4_dir_entry *)bh->b_data)) { 1442 EXT4_ERROR_INODE(dir, "checksumming directory " 1443 "block %lu", (unsigned long)block); 1444 brelse(bh); 1445 ret = ERR_PTR(-EFSBADCRC); 1446 goto cleanup_and_exit; 1447 } 1448 set_buffer_verified(bh); 1449 i = search_dirblock(bh, dir, &fname, 1450 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); 1451 if (i == 1) { 1452 EXT4_I(dir)->i_dir_start_lookup = block; 1453 ret = bh; 1454 goto cleanup_and_exit; 1455 } else { 1456 brelse(bh); 1457 if (i < 0) 1458 goto cleanup_and_exit; 1459 } 1460 next: 1461 if (++block >= nblocks) 1462 block = 0; 1463 } while (block != start); 1464 1465 /* 1466 * If the directory has grown while we were searching, then 1467 * search the last part of the directory before giving up. 1468 */ 1469 block = nblocks; 1470 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1471 if (block < nblocks) { 1472 start = 0; 1473 goto restart; 1474 } 1475 1476 cleanup_and_exit: 1477 /* Clean up the read-ahead blocks */ 1478 for (; ra_ptr < ra_max; ra_ptr++) 1479 brelse(bh_use[ra_ptr]); 1480 ext4_fname_free_filename(&fname); 1481 return ret; 1482 } 1483 1484 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 1485 struct ext4_filename *fname, 1486 struct ext4_dir_entry_2 **res_dir) 1487 { 1488 struct super_block * sb = dir->i_sb; 1489 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1490 struct buffer_head *bh; 1491 ext4_lblk_t block; 1492 int retval; 1493 1494 #ifdef CONFIG_EXT4_FS_ENCRYPTION 1495 *res_dir = NULL; 1496 #endif 1497 frame = dx_probe(fname, dir, NULL, frames); 1498 if (IS_ERR(frame)) 1499 return (struct buffer_head *) frame; 1500 do { 1501 block = dx_get_block(frame->at); 1502 bh = ext4_read_dirblock(dir, block, DIRENT); 1503 if (IS_ERR(bh)) 1504 goto errout; 1505 1506 retval = search_dirblock(bh, dir, fname, 1507 block << EXT4_BLOCK_SIZE_BITS(sb), 1508 res_dir); 1509 if (retval == 1) 1510 goto success; 1511 brelse(bh); 1512 if (retval == -1) { 1513 bh = ERR_PTR(ERR_BAD_DX_DIR); 1514 goto errout; 1515 } 1516 1517 /* Check to see if we should continue to search */ 1518 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame, 1519 frames, NULL); 1520 if (retval < 0) { 1521 ext4_warning_inode(dir, 1522 "error %d reading directory index block", 1523 retval); 1524 bh = ERR_PTR(retval); 1525 goto errout; 1526 } 1527 } while (retval == 1); 1528 1529 bh = NULL; 1530 errout: 1531 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name)); 1532 success: 1533 dx_release(frames); 1534 return bh; 1535 } 1536 1537 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 1538 { 1539 struct inode *inode; 1540 struct ext4_dir_entry_2 *de; 1541 struct buffer_head *bh; 1542 1543 if (ext4_encrypted_inode(dir)) { 1544 int res = fscrypt_get_encryption_info(dir); 1545 1546 /* 1547 * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is 1548 * created while the directory was encrypted and we 1549 * have access to the key. 1550 */ 1551 if (fscrypt_has_encryption_key(dir)) 1552 fscrypt_set_encrypted_dentry(dentry); 1553 fscrypt_set_d_op(dentry); 1554 if (res && res != -ENOKEY) 1555 return ERR_PTR(res); 1556 } 1557 1558 if (dentry->d_name.len > EXT4_NAME_LEN) 1559 return ERR_PTR(-ENAMETOOLONG); 1560 1561 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 1562 if (IS_ERR(bh)) 1563 return (struct dentry *) bh; 1564 inode = NULL; 1565 if (bh) { 1566 __u32 ino = le32_to_cpu(de->inode); 1567 brelse(bh); 1568 if (!ext4_valid_inum(dir->i_sb, ino)) { 1569 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); 1570 return ERR_PTR(-EFSCORRUPTED); 1571 } 1572 if (unlikely(ino == dir->i_ino)) { 1573 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir", 1574 dentry); 1575 return ERR_PTR(-EFSCORRUPTED); 1576 } 1577 inode = ext4_iget_normal(dir->i_sb, ino); 1578 if (inode == ERR_PTR(-ESTALE)) { 1579 EXT4_ERROR_INODE(dir, 1580 "deleted inode referenced: %u", 1581 ino); 1582 return ERR_PTR(-EFSCORRUPTED); 1583 } 1584 if (!IS_ERR(inode) && ext4_encrypted_inode(dir) && 1585 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && 1586 !fscrypt_has_permitted_context(dir, inode)) { 1587 ext4_warning(inode->i_sb, 1588 "Inconsistent encryption contexts: %lu/%lu", 1589 dir->i_ino, inode->i_ino); 1590 iput(inode); 1591 return ERR_PTR(-EPERM); 1592 } 1593 } 1594 return d_splice_alias(inode, dentry); 1595 } 1596 1597 1598 struct dentry *ext4_get_parent(struct dentry *child) 1599 { 1600 __u32 ino; 1601 static const struct qstr dotdot = QSTR_INIT("..", 2); 1602 struct ext4_dir_entry_2 * de; 1603 struct buffer_head *bh; 1604 1605 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL); 1606 if (IS_ERR(bh)) 1607 return (struct dentry *) bh; 1608 if (!bh) 1609 return ERR_PTR(-ENOENT); 1610 ino = le32_to_cpu(de->inode); 1611 brelse(bh); 1612 1613 if (!ext4_valid_inum(child->d_sb, ino)) { 1614 EXT4_ERROR_INODE(d_inode(child), 1615 "bad parent inode number: %u", ino); 1616 return ERR_PTR(-EFSCORRUPTED); 1617 } 1618 1619 return d_obtain_alias(ext4_iget_normal(child->d_sb, ino)); 1620 } 1621 1622 /* 1623 * Move count entries from end of map between two memory locations. 1624 * Returns pointer to last entry moved. 1625 */ 1626 static struct ext4_dir_entry_2 * 1627 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, 1628 unsigned blocksize) 1629 { 1630 unsigned rec_len = 0; 1631 1632 while (count--) { 1633 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) 1634 (from + (map->offs<<2)); 1635 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1636 memcpy (to, de, rec_len); 1637 ((struct ext4_dir_entry_2 *) to)->rec_len = 1638 ext4_rec_len_to_disk(rec_len, blocksize); 1639 de->inode = 0; 1640 map++; 1641 to += rec_len; 1642 } 1643 return (struct ext4_dir_entry_2 *) (to - rec_len); 1644 } 1645 1646 /* 1647 * Compact each dir entry in the range to the minimal rec_len. 1648 * Returns pointer to last entry in range. 1649 */ 1650 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) 1651 { 1652 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; 1653 unsigned rec_len = 0; 1654 1655 prev = to = de; 1656 while ((char*)de < base + blocksize) { 1657 next = ext4_next_entry(de, blocksize); 1658 if (de->inode && de->name_len) { 1659 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1660 if (de > to) 1661 memmove(to, de, rec_len); 1662 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); 1663 prev = to; 1664 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); 1665 } 1666 de = next; 1667 } 1668 return prev; 1669 } 1670 1671 /* 1672 * Split a full leaf block to make room for a new dir entry. 1673 * Allocate a new block, and move entries so that they are approx. equally full. 1674 * Returns pointer to de in block into which the new entry will be inserted. 1675 */ 1676 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1677 struct buffer_head **bh,struct dx_frame *frame, 1678 struct dx_hash_info *hinfo) 1679 { 1680 unsigned blocksize = dir->i_sb->s_blocksize; 1681 unsigned count, continued; 1682 struct buffer_head *bh2; 1683 ext4_lblk_t newblock; 1684 u32 hash2; 1685 struct dx_map_entry *map; 1686 char *data1 = (*bh)->b_data, *data2; 1687 unsigned split, move, size; 1688 struct ext4_dir_entry_2 *de = NULL, *de2; 1689 struct ext4_dir_entry_tail *t; 1690 int csum_size = 0; 1691 int err = 0, i; 1692 1693 if (ext4_has_metadata_csum(dir->i_sb)) 1694 csum_size = sizeof(struct ext4_dir_entry_tail); 1695 1696 bh2 = ext4_append(handle, dir, &newblock); 1697 if (IS_ERR(bh2)) { 1698 brelse(*bh); 1699 *bh = NULL; 1700 return (struct ext4_dir_entry_2 *) bh2; 1701 } 1702 1703 BUFFER_TRACE(*bh, "get_write_access"); 1704 err = ext4_journal_get_write_access(handle, *bh); 1705 if (err) 1706 goto journal_error; 1707 1708 BUFFER_TRACE(frame->bh, "get_write_access"); 1709 err = ext4_journal_get_write_access(handle, frame->bh); 1710 if (err) 1711 goto journal_error; 1712 1713 data2 = bh2->b_data; 1714 1715 /* create map in the end of data2 block */ 1716 map = (struct dx_map_entry *) (data2 + blocksize); 1717 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1, 1718 blocksize, hinfo, map); 1719 map -= count; 1720 dx_sort_map(map, count); 1721 /* Split the existing block in the middle, size-wise */ 1722 size = 0; 1723 move = 0; 1724 for (i = count-1; i >= 0; i--) { 1725 /* is more than half of this entry in 2nd half of the block? */ 1726 if (size + map[i].size/2 > blocksize/2) 1727 break; 1728 size += map[i].size; 1729 move++; 1730 } 1731 /* map index at which we will split */ 1732 split = count - move; 1733 hash2 = map[split].hash; 1734 continued = hash2 == map[split - 1].hash; 1735 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", 1736 (unsigned long)dx_get_block(frame->at), 1737 hash2, split, count-split)); 1738 1739 /* Fancy dance to stay within two buffers */ 1740 de2 = dx_move_dirents(data1, data2, map + split, count - split, 1741 blocksize); 1742 de = dx_pack_dirents(data1, blocksize); 1743 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1744 (char *) de, 1745 blocksize); 1746 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - 1747 (char *) de2, 1748 blocksize); 1749 if (csum_size) { 1750 t = EXT4_DIRENT_TAIL(data2, blocksize); 1751 initialize_dirent_tail(t, blocksize); 1752 1753 t = EXT4_DIRENT_TAIL(data1, blocksize); 1754 initialize_dirent_tail(t, blocksize); 1755 } 1756 1757 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1, 1758 blocksize, 1)); 1759 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2, 1760 blocksize, 1)); 1761 1762 /* Which block gets the new entry? */ 1763 if (hinfo->hash >= hash2) { 1764 swap(*bh, bh2); 1765 de = de2; 1766 } 1767 dx_insert_block(frame, hash2 + continued, newblock); 1768 err = ext4_handle_dirty_dirent_node(handle, dir, bh2); 1769 if (err) 1770 goto journal_error; 1771 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1772 if (err) 1773 goto journal_error; 1774 brelse(bh2); 1775 dxtrace(dx_show_index("frame", frame->entries)); 1776 return de; 1777 1778 journal_error: 1779 brelse(*bh); 1780 brelse(bh2); 1781 *bh = NULL; 1782 ext4_std_error(dir->i_sb, err); 1783 return ERR_PTR(err); 1784 } 1785 1786 int ext4_find_dest_de(struct inode *dir, struct inode *inode, 1787 struct buffer_head *bh, 1788 void *buf, int buf_size, 1789 struct ext4_filename *fname, 1790 struct ext4_dir_entry_2 **dest_de) 1791 { 1792 struct ext4_dir_entry_2 *de; 1793 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname)); 1794 int nlen, rlen; 1795 unsigned int offset = 0; 1796 char *top; 1797 1798 de = (struct ext4_dir_entry_2 *)buf; 1799 top = buf + buf_size - reclen; 1800 while ((char *) de <= top) { 1801 if (ext4_check_dir_entry(dir, NULL, de, bh, 1802 buf, buf_size, offset)) 1803 return -EFSCORRUPTED; 1804 if (ext4_match(fname, de)) 1805 return -EEXIST; 1806 nlen = EXT4_DIR_REC_LEN(de->name_len); 1807 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1808 if ((de->inode ? rlen - nlen : rlen) >= reclen) 1809 break; 1810 de = (struct ext4_dir_entry_2 *)((char *)de + rlen); 1811 offset += rlen; 1812 } 1813 if ((char *) de > top) 1814 return -ENOSPC; 1815 1816 *dest_de = de; 1817 return 0; 1818 } 1819 1820 void ext4_insert_dentry(struct inode *inode, 1821 struct ext4_dir_entry_2 *de, 1822 int buf_size, 1823 struct ext4_filename *fname) 1824 { 1825 1826 int nlen, rlen; 1827 1828 nlen = EXT4_DIR_REC_LEN(de->name_len); 1829 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1830 if (de->inode) { 1831 struct ext4_dir_entry_2 *de1 = 1832 (struct ext4_dir_entry_2 *)((char *)de + nlen); 1833 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); 1834 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); 1835 de = de1; 1836 } 1837 de->file_type = EXT4_FT_UNKNOWN; 1838 de->inode = cpu_to_le32(inode->i_ino); 1839 ext4_set_de_type(inode->i_sb, de, inode->i_mode); 1840 de->name_len = fname_len(fname); 1841 memcpy(de->name, fname_name(fname), fname_len(fname)); 1842 } 1843 1844 /* 1845 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1846 * it points to a directory entry which is guaranteed to be large 1847 * enough for new directory entry. If de is NULL, then 1848 * add_dirent_to_buf will attempt search the directory block for 1849 * space. It will return -ENOSPC if no space is available, and -EIO 1850 * and -EEXIST if directory entry already exists. 1851 */ 1852 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname, 1853 struct inode *dir, 1854 struct inode *inode, struct ext4_dir_entry_2 *de, 1855 struct buffer_head *bh) 1856 { 1857 unsigned int blocksize = dir->i_sb->s_blocksize; 1858 int csum_size = 0; 1859 int err; 1860 1861 if (ext4_has_metadata_csum(inode->i_sb)) 1862 csum_size = sizeof(struct ext4_dir_entry_tail); 1863 1864 if (!de) { 1865 err = ext4_find_dest_de(dir, inode, bh, bh->b_data, 1866 blocksize - csum_size, fname, &de); 1867 if (err) 1868 return err; 1869 } 1870 BUFFER_TRACE(bh, "get_write_access"); 1871 err = ext4_journal_get_write_access(handle, bh); 1872 if (err) { 1873 ext4_std_error(dir->i_sb, err); 1874 return err; 1875 } 1876 1877 /* By now the buffer is marked for journaling */ 1878 ext4_insert_dentry(inode, de, blocksize, fname); 1879 1880 /* 1881 * XXX shouldn't update any times until successful 1882 * completion of syscall, but too many callers depend 1883 * on this. 1884 * 1885 * XXX similarly, too many callers depend on 1886 * ext4_new_inode() setting the times, but error 1887 * recovery deletes the inode, so the worst that can 1888 * happen is that the times are slightly out of date 1889 * and/or different from the directory change time. 1890 */ 1891 dir->i_mtime = dir->i_ctime = current_time(dir); 1892 ext4_update_dx_flag(dir); 1893 inode_inc_iversion(dir); 1894 ext4_mark_inode_dirty(handle, dir); 1895 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 1896 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 1897 if (err) 1898 ext4_std_error(dir->i_sb, err); 1899 return 0; 1900 } 1901 1902 /* 1903 * This converts a one block unindexed directory to a 3 block indexed 1904 * directory, and adds the dentry to the indexed directory. 1905 */ 1906 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, 1907 struct inode *dir, 1908 struct inode *inode, struct buffer_head *bh) 1909 { 1910 struct buffer_head *bh2; 1911 struct dx_root *root; 1912 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1913 struct dx_entry *entries; 1914 struct ext4_dir_entry_2 *de, *de2; 1915 struct ext4_dir_entry_tail *t; 1916 char *data1, *top; 1917 unsigned len; 1918 int retval; 1919 unsigned blocksize; 1920 ext4_lblk_t block; 1921 struct fake_dirent *fde; 1922 int csum_size = 0; 1923 1924 if (ext4_has_metadata_csum(inode->i_sb)) 1925 csum_size = sizeof(struct ext4_dir_entry_tail); 1926 1927 blocksize = dir->i_sb->s_blocksize; 1928 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); 1929 BUFFER_TRACE(bh, "get_write_access"); 1930 retval = ext4_journal_get_write_access(handle, bh); 1931 if (retval) { 1932 ext4_std_error(dir->i_sb, retval); 1933 brelse(bh); 1934 return retval; 1935 } 1936 root = (struct dx_root *) bh->b_data; 1937 1938 /* The 0th block becomes the root, move the dirents out */ 1939 fde = &root->dotdot; 1940 de = (struct ext4_dir_entry_2 *)((char *)fde + 1941 ext4_rec_len_from_disk(fde->rec_len, blocksize)); 1942 if ((char *) de >= (((char *) root) + blocksize)) { 1943 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); 1944 brelse(bh); 1945 return -EFSCORRUPTED; 1946 } 1947 len = ((char *) root) + (blocksize - csum_size) - (char *) de; 1948 1949 /* Allocate new block for the 0th block's dirents */ 1950 bh2 = ext4_append(handle, dir, &block); 1951 if (IS_ERR(bh2)) { 1952 brelse(bh); 1953 return PTR_ERR(bh2); 1954 } 1955 ext4_set_inode_flag(dir, EXT4_INODE_INDEX); 1956 data1 = bh2->b_data; 1957 1958 memcpy (data1, de, len); 1959 de = (struct ext4_dir_entry_2 *) data1; 1960 top = data1 + len; 1961 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) 1962 de = de2; 1963 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1964 (char *) de, 1965 blocksize); 1966 1967 if (csum_size) { 1968 t = EXT4_DIRENT_TAIL(data1, blocksize); 1969 initialize_dirent_tail(t, blocksize); 1970 } 1971 1972 /* Initialize the root; the dot dirents already exist */ 1973 de = (struct ext4_dir_entry_2 *) (&root->dotdot); 1974 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), 1975 blocksize); 1976 memset (&root->info, 0, sizeof(root->info)); 1977 root->info.info_length = sizeof(root->info); 1978 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1979 entries = root->entries; 1980 dx_set_block(entries, 1); 1981 dx_set_count(entries, 1); 1982 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); 1983 1984 /* Initialize as for dx_probe */ 1985 fname->hinfo.hash_version = root->info.hash_version; 1986 if (fname->hinfo.hash_version <= DX_HASH_TEA) 1987 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 1988 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1989 ext4fs_dirhash(fname_name(fname), fname_len(fname), &fname->hinfo); 1990 1991 memset(frames, 0, sizeof(frames)); 1992 frame = frames; 1993 frame->entries = entries; 1994 frame->at = entries; 1995 frame->bh = bh; 1996 1997 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1998 if (retval) 1999 goto out_frames; 2000 retval = ext4_handle_dirty_dirent_node(handle, dir, bh2); 2001 if (retval) 2002 goto out_frames; 2003 2004 de = do_split(handle,dir, &bh2, frame, &fname->hinfo); 2005 if (IS_ERR(de)) { 2006 retval = PTR_ERR(de); 2007 goto out_frames; 2008 } 2009 2010 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2); 2011 out_frames: 2012 /* 2013 * Even if the block split failed, we have to properly write 2014 * out all the changes we did so far. Otherwise we can end up 2015 * with corrupted filesystem. 2016 */ 2017 if (retval) 2018 ext4_mark_inode_dirty(handle, dir); 2019 dx_release(frames); 2020 brelse(bh2); 2021 return retval; 2022 } 2023 2024 /* 2025 * ext4_add_entry() 2026 * 2027 * adds a file entry to the specified directory, using the same 2028 * semantics as ext4_find_entry(). It returns NULL if it failed. 2029 * 2030 * NOTE!! The inode part of 'de' is left at 0 - which means you 2031 * may not sleep between calling this and putting something into 2032 * the entry, as someone else might have used it while you slept. 2033 */ 2034 static int ext4_add_entry(handle_t *handle, struct dentry *dentry, 2035 struct inode *inode) 2036 { 2037 struct inode *dir = d_inode(dentry->d_parent); 2038 struct buffer_head *bh = NULL; 2039 struct ext4_dir_entry_2 *de; 2040 struct ext4_dir_entry_tail *t; 2041 struct super_block *sb; 2042 struct ext4_filename fname; 2043 int retval; 2044 int dx_fallback=0; 2045 unsigned blocksize; 2046 ext4_lblk_t block, blocks; 2047 int csum_size = 0; 2048 2049 if (ext4_has_metadata_csum(inode->i_sb)) 2050 csum_size = sizeof(struct ext4_dir_entry_tail); 2051 2052 sb = dir->i_sb; 2053 blocksize = sb->s_blocksize; 2054 if (!dentry->d_name.len) 2055 return -EINVAL; 2056 2057 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname); 2058 if (retval) 2059 return retval; 2060 2061 if (ext4_has_inline_data(dir)) { 2062 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode); 2063 if (retval < 0) 2064 goto out; 2065 if (retval == 1) { 2066 retval = 0; 2067 goto out; 2068 } 2069 } 2070 2071 if (is_dx(dir)) { 2072 retval = ext4_dx_add_entry(handle, &fname, dir, inode); 2073 if (!retval || (retval != ERR_BAD_DX_DIR)) 2074 goto out; 2075 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); 2076 dx_fallback++; 2077 ext4_mark_inode_dirty(handle, dir); 2078 } 2079 blocks = dir->i_size >> sb->s_blocksize_bits; 2080 for (block = 0; block < blocks; block++) { 2081 bh = ext4_read_dirblock(dir, block, DIRENT); 2082 if (IS_ERR(bh)) { 2083 retval = PTR_ERR(bh); 2084 bh = NULL; 2085 goto out; 2086 } 2087 retval = add_dirent_to_buf(handle, &fname, dir, inode, 2088 NULL, bh); 2089 if (retval != -ENOSPC) 2090 goto out; 2091 2092 if (blocks == 1 && !dx_fallback && 2093 ext4_has_feature_dir_index(sb)) { 2094 retval = make_indexed_dir(handle, &fname, dir, 2095 inode, bh); 2096 bh = NULL; /* make_indexed_dir releases bh */ 2097 goto out; 2098 } 2099 brelse(bh); 2100 } 2101 bh = ext4_append(handle, dir, &block); 2102 if (IS_ERR(bh)) { 2103 retval = PTR_ERR(bh); 2104 bh = NULL; 2105 goto out; 2106 } 2107 de = (struct ext4_dir_entry_2 *) bh->b_data; 2108 de->inode = 0; 2109 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize); 2110 2111 if (csum_size) { 2112 t = EXT4_DIRENT_TAIL(bh->b_data, blocksize); 2113 initialize_dirent_tail(t, blocksize); 2114 } 2115 2116 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh); 2117 out: 2118 ext4_fname_free_filename(&fname); 2119 brelse(bh); 2120 if (retval == 0) 2121 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); 2122 return retval; 2123 } 2124 2125 /* 2126 * Returns 0 for success, or a negative error value 2127 */ 2128 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 2129 struct inode *dir, struct inode *inode) 2130 { 2131 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 2132 struct dx_entry *entries, *at; 2133 struct buffer_head *bh; 2134 struct super_block *sb = dir->i_sb; 2135 struct ext4_dir_entry_2 *de; 2136 int restart; 2137 int err; 2138 2139 again: 2140 restart = 0; 2141 frame = dx_probe(fname, dir, NULL, frames); 2142 if (IS_ERR(frame)) 2143 return PTR_ERR(frame); 2144 entries = frame->entries; 2145 at = frame->at; 2146 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT); 2147 if (IS_ERR(bh)) { 2148 err = PTR_ERR(bh); 2149 bh = NULL; 2150 goto cleanup; 2151 } 2152 2153 BUFFER_TRACE(bh, "get_write_access"); 2154 err = ext4_journal_get_write_access(handle, bh); 2155 if (err) 2156 goto journal_error; 2157 2158 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh); 2159 if (err != -ENOSPC) 2160 goto cleanup; 2161 2162 err = 0; 2163 /* Block full, should compress but for now just split */ 2164 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n", 2165 dx_get_count(entries), dx_get_limit(entries))); 2166 /* Need to split index? */ 2167 if (dx_get_count(entries) == dx_get_limit(entries)) { 2168 ext4_lblk_t newblock; 2169 int levels = frame - frames + 1; 2170 unsigned int icount; 2171 int add_level = 1; 2172 struct dx_entry *entries2; 2173 struct dx_node *node2; 2174 struct buffer_head *bh2; 2175 2176 while (frame > frames) { 2177 if (dx_get_count((frame - 1)->entries) < 2178 dx_get_limit((frame - 1)->entries)) { 2179 add_level = 0; 2180 break; 2181 } 2182 frame--; /* split higher index block */ 2183 at = frame->at; 2184 entries = frame->entries; 2185 restart = 1; 2186 } 2187 if (add_level && levels == ext4_dir_htree_level(sb)) { 2188 ext4_warning(sb, "Directory (ino: %lu) index full, " 2189 "reach max htree level :%d", 2190 dir->i_ino, levels); 2191 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) { 2192 ext4_warning(sb, "Large directory feature is " 2193 "not enabled on this " 2194 "filesystem"); 2195 } 2196 err = -ENOSPC; 2197 goto cleanup; 2198 } 2199 icount = dx_get_count(entries); 2200 bh2 = ext4_append(handle, dir, &newblock); 2201 if (IS_ERR(bh2)) { 2202 err = PTR_ERR(bh2); 2203 goto cleanup; 2204 } 2205 node2 = (struct dx_node *)(bh2->b_data); 2206 entries2 = node2->entries; 2207 memset(&node2->fake, 0, sizeof(struct fake_dirent)); 2208 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, 2209 sb->s_blocksize); 2210 BUFFER_TRACE(frame->bh, "get_write_access"); 2211 err = ext4_journal_get_write_access(handle, frame->bh); 2212 if (err) 2213 goto journal_error; 2214 if (!add_level) { 2215 unsigned icount1 = icount/2, icount2 = icount - icount1; 2216 unsigned hash2 = dx_get_hash(entries + icount1); 2217 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n", 2218 icount1, icount2)); 2219 2220 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 2221 err = ext4_journal_get_write_access(handle, 2222 (frame - 1)->bh); 2223 if (err) 2224 goto journal_error; 2225 2226 memcpy((char *) entries2, (char *) (entries + icount1), 2227 icount2 * sizeof(struct dx_entry)); 2228 dx_set_count(entries, icount1); 2229 dx_set_count(entries2, icount2); 2230 dx_set_limit(entries2, dx_node_limit(dir)); 2231 2232 /* Which index block gets the new entry? */ 2233 if (at - entries >= icount1) { 2234 frame->at = at = at - entries - icount1 + entries2; 2235 frame->entries = entries = entries2; 2236 swap(frame->bh, bh2); 2237 } 2238 dx_insert_block((frame - 1), hash2, newblock); 2239 dxtrace(dx_show_index("node", frame->entries)); 2240 dxtrace(dx_show_index("node", 2241 ((struct dx_node *) bh2->b_data)->entries)); 2242 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2243 if (err) 2244 goto journal_error; 2245 brelse (bh2); 2246 err = ext4_handle_dirty_dx_node(handle, dir, 2247 (frame - 1)->bh); 2248 if (err) 2249 goto journal_error; 2250 if (restart) { 2251 err = ext4_handle_dirty_dx_node(handle, dir, 2252 frame->bh); 2253 goto journal_error; 2254 } 2255 } else { 2256 struct dx_root *dxroot; 2257 memcpy((char *) entries2, (char *) entries, 2258 icount * sizeof(struct dx_entry)); 2259 dx_set_limit(entries2, dx_node_limit(dir)); 2260 2261 /* Set up root */ 2262 dx_set_count(entries, 1); 2263 dx_set_block(entries + 0, newblock); 2264 dxroot = (struct dx_root *)frames[0].bh->b_data; 2265 dxroot->info.indirect_levels += 1; 2266 dxtrace(printk(KERN_DEBUG 2267 "Creating %d level index...\n", 2268 info->indirect_levels)); 2269 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2270 if (err) 2271 goto journal_error; 2272 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2273 brelse(bh2); 2274 restart = 1; 2275 goto journal_error; 2276 } 2277 } 2278 de = do_split(handle, dir, &bh, frame, &fname->hinfo); 2279 if (IS_ERR(de)) { 2280 err = PTR_ERR(de); 2281 goto cleanup; 2282 } 2283 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh); 2284 goto cleanup; 2285 2286 journal_error: 2287 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */ 2288 cleanup: 2289 brelse(bh); 2290 dx_release(frames); 2291 /* @restart is true means htree-path has been changed, we need to 2292 * repeat dx_probe() to find out valid htree-path 2293 */ 2294 if (restart && err == 0) 2295 goto again; 2296 return err; 2297 } 2298 2299 /* 2300 * ext4_generic_delete_entry deletes a directory entry by merging it 2301 * with the previous entry 2302 */ 2303 int ext4_generic_delete_entry(handle_t *handle, 2304 struct inode *dir, 2305 struct ext4_dir_entry_2 *de_del, 2306 struct buffer_head *bh, 2307 void *entry_buf, 2308 int buf_size, 2309 int csum_size) 2310 { 2311 struct ext4_dir_entry_2 *de, *pde; 2312 unsigned int blocksize = dir->i_sb->s_blocksize; 2313 int i; 2314 2315 i = 0; 2316 pde = NULL; 2317 de = (struct ext4_dir_entry_2 *)entry_buf; 2318 while (i < buf_size - csum_size) { 2319 if (ext4_check_dir_entry(dir, NULL, de, bh, 2320 bh->b_data, bh->b_size, i)) 2321 return -EFSCORRUPTED; 2322 if (de == de_del) { 2323 if (pde) 2324 pde->rec_len = ext4_rec_len_to_disk( 2325 ext4_rec_len_from_disk(pde->rec_len, 2326 blocksize) + 2327 ext4_rec_len_from_disk(de->rec_len, 2328 blocksize), 2329 blocksize); 2330 else 2331 de->inode = 0; 2332 inode_inc_iversion(dir); 2333 return 0; 2334 } 2335 i += ext4_rec_len_from_disk(de->rec_len, blocksize); 2336 pde = de; 2337 de = ext4_next_entry(de, blocksize); 2338 } 2339 return -ENOENT; 2340 } 2341 2342 static int ext4_delete_entry(handle_t *handle, 2343 struct inode *dir, 2344 struct ext4_dir_entry_2 *de_del, 2345 struct buffer_head *bh) 2346 { 2347 int err, csum_size = 0; 2348 2349 if (ext4_has_inline_data(dir)) { 2350 int has_inline_data = 1; 2351 err = ext4_delete_inline_entry(handle, dir, de_del, bh, 2352 &has_inline_data); 2353 if (has_inline_data) 2354 return err; 2355 } 2356 2357 if (ext4_has_metadata_csum(dir->i_sb)) 2358 csum_size = sizeof(struct ext4_dir_entry_tail); 2359 2360 BUFFER_TRACE(bh, "get_write_access"); 2361 err = ext4_journal_get_write_access(handle, bh); 2362 if (unlikely(err)) 2363 goto out; 2364 2365 err = ext4_generic_delete_entry(handle, dir, de_del, 2366 bh, bh->b_data, 2367 dir->i_sb->s_blocksize, csum_size); 2368 if (err) 2369 goto out; 2370 2371 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 2372 err = ext4_handle_dirty_dirent_node(handle, dir, bh); 2373 if (unlikely(err)) 2374 goto out; 2375 2376 return 0; 2377 out: 2378 if (err != -ENOENT) 2379 ext4_std_error(dir->i_sb, err); 2380 return err; 2381 } 2382 2383 /* 2384 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2 2385 * since this indicates that nlinks count was previously 1 to avoid overflowing 2386 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean 2387 * that subdirectory link counts are not being maintained accurately. 2388 * 2389 * The caller has already checked for i_nlink overflow in case the DIR_LINK 2390 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy 2391 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set 2392 * on regular files) and to avoid creating huge/slow non-HTREE directories. 2393 */ 2394 static void ext4_inc_count(handle_t *handle, struct inode *inode) 2395 { 2396 inc_nlink(inode); 2397 if (is_dx(inode) && 2398 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2)) 2399 set_nlink(inode, 1); 2400 } 2401 2402 /* 2403 * If a directory had nlink == 1, then we should let it be 1. This indicates 2404 * directory has >EXT4_LINK_MAX subdirs. 2405 */ 2406 static void ext4_dec_count(handle_t *handle, struct inode *inode) 2407 { 2408 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) 2409 drop_nlink(inode); 2410 } 2411 2412 2413 static int ext4_add_nondir(handle_t *handle, 2414 struct dentry *dentry, struct inode *inode) 2415 { 2416 int err = ext4_add_entry(handle, dentry, inode); 2417 if (!err) { 2418 ext4_mark_inode_dirty(handle, inode); 2419 unlock_new_inode(inode); 2420 d_instantiate(dentry, inode); 2421 return 0; 2422 } 2423 drop_nlink(inode); 2424 unlock_new_inode(inode); 2425 iput(inode); 2426 return err; 2427 } 2428 2429 /* 2430 * By the time this is called, we already have created 2431 * the directory cache entry for the new file, but it 2432 * is so far negative - it has no inode. 2433 * 2434 * If the create succeeds, we fill in the inode information 2435 * with d_instantiate(). 2436 */ 2437 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, 2438 bool excl) 2439 { 2440 handle_t *handle; 2441 struct inode *inode; 2442 int err, credits, retries = 0; 2443 2444 err = dquot_initialize(dir); 2445 if (err) 2446 return err; 2447 2448 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2449 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2450 retry: 2451 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2452 NULL, EXT4_HT_DIR, credits); 2453 handle = ext4_journal_current_handle(); 2454 err = PTR_ERR(inode); 2455 if (!IS_ERR(inode)) { 2456 inode->i_op = &ext4_file_inode_operations; 2457 inode->i_fop = &ext4_file_operations; 2458 ext4_set_aops(inode); 2459 err = ext4_add_nondir(handle, dentry, inode); 2460 if (!err && IS_DIRSYNC(dir)) 2461 ext4_handle_sync(handle); 2462 } 2463 if (handle) 2464 ext4_journal_stop(handle); 2465 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2466 goto retry; 2467 return err; 2468 } 2469 2470 static int ext4_mknod(struct inode *dir, struct dentry *dentry, 2471 umode_t mode, dev_t rdev) 2472 { 2473 handle_t *handle; 2474 struct inode *inode; 2475 int err, credits, retries = 0; 2476 2477 err = dquot_initialize(dir); 2478 if (err) 2479 return err; 2480 2481 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2482 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2483 retry: 2484 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2485 NULL, EXT4_HT_DIR, credits); 2486 handle = ext4_journal_current_handle(); 2487 err = PTR_ERR(inode); 2488 if (!IS_ERR(inode)) { 2489 init_special_inode(inode, inode->i_mode, rdev); 2490 inode->i_op = &ext4_special_inode_operations; 2491 err = ext4_add_nondir(handle, dentry, inode); 2492 if (!err && IS_DIRSYNC(dir)) 2493 ext4_handle_sync(handle); 2494 } 2495 if (handle) 2496 ext4_journal_stop(handle); 2497 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2498 goto retry; 2499 return err; 2500 } 2501 2502 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 2503 { 2504 handle_t *handle; 2505 struct inode *inode; 2506 int err, retries = 0; 2507 2508 err = dquot_initialize(dir); 2509 if (err) 2510 return err; 2511 2512 retry: 2513 inode = ext4_new_inode_start_handle(dir, mode, 2514 NULL, 0, NULL, 2515 EXT4_HT_DIR, 2516 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 2517 4 + EXT4_XATTR_TRANS_BLOCKS); 2518 handle = ext4_journal_current_handle(); 2519 err = PTR_ERR(inode); 2520 if (!IS_ERR(inode)) { 2521 inode->i_op = &ext4_file_inode_operations; 2522 inode->i_fop = &ext4_file_operations; 2523 ext4_set_aops(inode); 2524 d_tmpfile(dentry, inode); 2525 err = ext4_orphan_add(handle, inode); 2526 if (err) 2527 goto err_unlock_inode; 2528 mark_inode_dirty(inode); 2529 unlock_new_inode(inode); 2530 } 2531 if (handle) 2532 ext4_journal_stop(handle); 2533 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2534 goto retry; 2535 return err; 2536 err_unlock_inode: 2537 ext4_journal_stop(handle); 2538 unlock_new_inode(inode); 2539 return err; 2540 } 2541 2542 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode, 2543 struct ext4_dir_entry_2 *de, 2544 int blocksize, int csum_size, 2545 unsigned int parent_ino, int dotdot_real_len) 2546 { 2547 de->inode = cpu_to_le32(inode->i_ino); 2548 de->name_len = 1; 2549 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), 2550 blocksize); 2551 strcpy(de->name, "."); 2552 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2553 2554 de = ext4_next_entry(de, blocksize); 2555 de->inode = cpu_to_le32(parent_ino); 2556 de->name_len = 2; 2557 if (!dotdot_real_len) 2558 de->rec_len = ext4_rec_len_to_disk(blocksize - 2559 (csum_size + EXT4_DIR_REC_LEN(1)), 2560 blocksize); 2561 else 2562 de->rec_len = ext4_rec_len_to_disk( 2563 EXT4_DIR_REC_LEN(de->name_len), blocksize); 2564 strcpy(de->name, ".."); 2565 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2566 2567 return ext4_next_entry(de, blocksize); 2568 } 2569 2570 static int ext4_init_new_dir(handle_t *handle, struct inode *dir, 2571 struct inode *inode) 2572 { 2573 struct buffer_head *dir_block = NULL; 2574 struct ext4_dir_entry_2 *de; 2575 struct ext4_dir_entry_tail *t; 2576 ext4_lblk_t block = 0; 2577 unsigned int blocksize = dir->i_sb->s_blocksize; 2578 int csum_size = 0; 2579 int err; 2580 2581 if (ext4_has_metadata_csum(dir->i_sb)) 2582 csum_size = sizeof(struct ext4_dir_entry_tail); 2583 2584 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { 2585 err = ext4_try_create_inline_dir(handle, dir, inode); 2586 if (err < 0 && err != -ENOSPC) 2587 goto out; 2588 if (!err) 2589 goto out; 2590 } 2591 2592 inode->i_size = 0; 2593 dir_block = ext4_append(handle, inode, &block); 2594 if (IS_ERR(dir_block)) 2595 return PTR_ERR(dir_block); 2596 de = (struct ext4_dir_entry_2 *)dir_block->b_data; 2597 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0); 2598 set_nlink(inode, 2); 2599 if (csum_size) { 2600 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize); 2601 initialize_dirent_tail(t, blocksize); 2602 } 2603 2604 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); 2605 err = ext4_handle_dirty_dirent_node(handle, inode, dir_block); 2606 if (err) 2607 goto out; 2608 set_buffer_verified(dir_block); 2609 out: 2610 brelse(dir_block); 2611 return err; 2612 } 2613 2614 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2615 { 2616 handle_t *handle; 2617 struct inode *inode; 2618 int err, credits, retries = 0; 2619 2620 if (EXT4_DIR_LINK_MAX(dir)) 2621 return -EMLINK; 2622 2623 err = dquot_initialize(dir); 2624 if (err) 2625 return err; 2626 2627 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2628 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2629 retry: 2630 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode, 2631 &dentry->d_name, 2632 0, NULL, EXT4_HT_DIR, credits); 2633 handle = ext4_journal_current_handle(); 2634 err = PTR_ERR(inode); 2635 if (IS_ERR(inode)) 2636 goto out_stop; 2637 2638 inode->i_op = &ext4_dir_inode_operations; 2639 inode->i_fop = &ext4_dir_operations; 2640 err = ext4_init_new_dir(handle, dir, inode); 2641 if (err) 2642 goto out_clear_inode; 2643 err = ext4_mark_inode_dirty(handle, inode); 2644 if (!err) 2645 err = ext4_add_entry(handle, dentry, inode); 2646 if (err) { 2647 out_clear_inode: 2648 clear_nlink(inode); 2649 unlock_new_inode(inode); 2650 ext4_mark_inode_dirty(handle, inode); 2651 iput(inode); 2652 goto out_stop; 2653 } 2654 ext4_inc_count(handle, dir); 2655 ext4_update_dx_flag(dir); 2656 err = ext4_mark_inode_dirty(handle, dir); 2657 if (err) 2658 goto out_clear_inode; 2659 unlock_new_inode(inode); 2660 d_instantiate(dentry, inode); 2661 if (IS_DIRSYNC(dir)) 2662 ext4_handle_sync(handle); 2663 2664 out_stop: 2665 if (handle) 2666 ext4_journal_stop(handle); 2667 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2668 goto retry; 2669 return err; 2670 } 2671 2672 /* 2673 * routine to check that the specified directory is empty (for rmdir) 2674 */ 2675 bool ext4_empty_dir(struct inode *inode) 2676 { 2677 unsigned int offset; 2678 struct buffer_head *bh; 2679 struct ext4_dir_entry_2 *de, *de1; 2680 struct super_block *sb; 2681 2682 if (ext4_has_inline_data(inode)) { 2683 int has_inline_data = 1; 2684 int ret; 2685 2686 ret = empty_inline_dir(inode, &has_inline_data); 2687 if (has_inline_data) 2688 return ret; 2689 } 2690 2691 sb = inode->i_sb; 2692 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { 2693 EXT4_ERROR_INODE(inode, "invalid size"); 2694 return true; 2695 } 2696 bh = ext4_read_dirblock(inode, 0, EITHER); 2697 if (IS_ERR(bh)) 2698 return true; 2699 2700 de = (struct ext4_dir_entry_2 *) bh->b_data; 2701 de1 = ext4_next_entry(de, sb->s_blocksize); 2702 if (le32_to_cpu(de->inode) != inode->i_ino || 2703 le32_to_cpu(de1->inode) == 0 || 2704 strcmp(".", de->name) || strcmp("..", de1->name)) { 2705 ext4_warning_inode(inode, "directory missing '.' and/or '..'"); 2706 brelse(bh); 2707 return true; 2708 } 2709 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + 2710 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); 2711 de = ext4_next_entry(de1, sb->s_blocksize); 2712 while (offset < inode->i_size) { 2713 if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 2714 unsigned int lblock; 2715 brelse(bh); 2716 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); 2717 bh = ext4_read_dirblock(inode, lblock, EITHER); 2718 if (IS_ERR(bh)) 2719 return true; 2720 de = (struct ext4_dir_entry_2 *) bh->b_data; 2721 } 2722 if (ext4_check_dir_entry(inode, NULL, de, bh, 2723 bh->b_data, bh->b_size, offset)) { 2724 de = (struct ext4_dir_entry_2 *)(bh->b_data + 2725 sb->s_blocksize); 2726 offset = (offset | (sb->s_blocksize - 1)) + 1; 2727 continue; 2728 } 2729 if (le32_to_cpu(de->inode)) { 2730 brelse(bh); 2731 return false; 2732 } 2733 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2734 de = ext4_next_entry(de, sb->s_blocksize); 2735 } 2736 brelse(bh); 2737 return true; 2738 } 2739 2740 /* 2741 * ext4_orphan_add() links an unlinked or truncated inode into a list of 2742 * such inodes, starting at the superblock, in case we crash before the 2743 * file is closed/deleted, or in case the inode truncate spans multiple 2744 * transactions and the last transaction is not recovered after a crash. 2745 * 2746 * At filesystem recovery time, we walk this list deleting unlinked 2747 * inodes and truncating linked inodes in ext4_orphan_cleanup(). 2748 * 2749 * Orphan list manipulation functions must be called under i_mutex unless 2750 * we are just creating the inode or deleting it. 2751 */ 2752 int ext4_orphan_add(handle_t *handle, struct inode *inode) 2753 { 2754 struct super_block *sb = inode->i_sb; 2755 struct ext4_sb_info *sbi = EXT4_SB(sb); 2756 struct ext4_iloc iloc; 2757 int err = 0, rc; 2758 bool dirty = false; 2759 2760 if (!sbi->s_journal || is_bad_inode(inode)) 2761 return 0; 2762 2763 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2764 !inode_is_locked(inode)); 2765 /* 2766 * Exit early if inode already is on orphan list. This is a big speedup 2767 * since we don't have to contend on the global s_orphan_lock. 2768 */ 2769 if (!list_empty(&EXT4_I(inode)->i_orphan)) 2770 return 0; 2771 2772 /* 2773 * Orphan handling is only valid for files with data blocks 2774 * being truncated, or files being unlinked. Note that we either 2775 * hold i_mutex, or the inode can not be referenced from outside, 2776 * so i_nlink should not be bumped due to race 2777 */ 2778 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2779 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 2780 2781 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2782 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2783 if (err) 2784 goto out; 2785 2786 err = ext4_reserve_inode_write(handle, inode, &iloc); 2787 if (err) 2788 goto out; 2789 2790 mutex_lock(&sbi->s_orphan_lock); 2791 /* 2792 * Due to previous errors inode may be already a part of on-disk 2793 * orphan list. If so skip on-disk list modification. 2794 */ 2795 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) > 2796 (le32_to_cpu(sbi->s_es->s_inodes_count))) { 2797 /* Insert this inode at the head of the on-disk orphan list */ 2798 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan); 2799 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 2800 dirty = true; 2801 } 2802 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan); 2803 mutex_unlock(&sbi->s_orphan_lock); 2804 2805 if (dirty) { 2806 err = ext4_handle_dirty_super(handle, sb); 2807 rc = ext4_mark_iloc_dirty(handle, inode, &iloc); 2808 if (!err) 2809 err = rc; 2810 if (err) { 2811 /* 2812 * We have to remove inode from in-memory list if 2813 * addition to on disk orphan list failed. Stray orphan 2814 * list entries can cause panics at unmount time. 2815 */ 2816 mutex_lock(&sbi->s_orphan_lock); 2817 list_del_init(&EXT4_I(inode)->i_orphan); 2818 mutex_unlock(&sbi->s_orphan_lock); 2819 } 2820 } 2821 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 2822 jbd_debug(4, "orphan inode %lu will point to %d\n", 2823 inode->i_ino, NEXT_ORPHAN(inode)); 2824 out: 2825 ext4_std_error(sb, err); 2826 return err; 2827 } 2828 2829 /* 2830 * ext4_orphan_del() removes an unlinked or truncated inode from the list 2831 * of such inodes stored on disk, because it is finally being cleaned up. 2832 */ 2833 int ext4_orphan_del(handle_t *handle, struct inode *inode) 2834 { 2835 struct list_head *prev; 2836 struct ext4_inode_info *ei = EXT4_I(inode); 2837 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 2838 __u32 ino_next; 2839 struct ext4_iloc iloc; 2840 int err = 0; 2841 2842 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS)) 2843 return 0; 2844 2845 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2846 !inode_is_locked(inode)); 2847 /* Do this quick check before taking global s_orphan_lock. */ 2848 if (list_empty(&ei->i_orphan)) 2849 return 0; 2850 2851 if (handle) { 2852 /* Grab inode buffer early before taking global s_orphan_lock */ 2853 err = ext4_reserve_inode_write(handle, inode, &iloc); 2854 } 2855 2856 mutex_lock(&sbi->s_orphan_lock); 2857 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 2858 2859 prev = ei->i_orphan.prev; 2860 list_del_init(&ei->i_orphan); 2861 2862 /* If we're on an error path, we may not have a valid 2863 * transaction handle with which to update the orphan list on 2864 * disk, but we still need to remove the inode from the linked 2865 * list in memory. */ 2866 if (!handle || err) { 2867 mutex_unlock(&sbi->s_orphan_lock); 2868 goto out_err; 2869 } 2870 2871 ino_next = NEXT_ORPHAN(inode); 2872 if (prev == &sbi->s_orphan) { 2873 jbd_debug(4, "superblock will point to %u\n", ino_next); 2874 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2875 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2876 if (err) { 2877 mutex_unlock(&sbi->s_orphan_lock); 2878 goto out_brelse; 2879 } 2880 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 2881 mutex_unlock(&sbi->s_orphan_lock); 2882 err = ext4_handle_dirty_super(handle, inode->i_sb); 2883 } else { 2884 struct ext4_iloc iloc2; 2885 struct inode *i_prev = 2886 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; 2887 2888 jbd_debug(4, "orphan inode %lu will point to %u\n", 2889 i_prev->i_ino, ino_next); 2890 err = ext4_reserve_inode_write(handle, i_prev, &iloc2); 2891 if (err) { 2892 mutex_unlock(&sbi->s_orphan_lock); 2893 goto out_brelse; 2894 } 2895 NEXT_ORPHAN(i_prev) = ino_next; 2896 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); 2897 mutex_unlock(&sbi->s_orphan_lock); 2898 } 2899 if (err) 2900 goto out_brelse; 2901 NEXT_ORPHAN(inode) = 0; 2902 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 2903 out_err: 2904 ext4_std_error(inode->i_sb, err); 2905 return err; 2906 2907 out_brelse: 2908 brelse(iloc.bh); 2909 goto out_err; 2910 } 2911 2912 static int ext4_rmdir(struct inode *dir, struct dentry *dentry) 2913 { 2914 int retval; 2915 struct inode *inode; 2916 struct buffer_head *bh; 2917 struct ext4_dir_entry_2 *de; 2918 handle_t *handle = NULL; 2919 2920 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 2921 return -EIO; 2922 2923 /* Initialize quotas before so that eventual writes go in 2924 * separate transaction */ 2925 retval = dquot_initialize(dir); 2926 if (retval) 2927 return retval; 2928 retval = dquot_initialize(d_inode(dentry)); 2929 if (retval) 2930 return retval; 2931 2932 retval = -ENOENT; 2933 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 2934 if (IS_ERR(bh)) 2935 return PTR_ERR(bh); 2936 if (!bh) 2937 goto end_rmdir; 2938 2939 inode = d_inode(dentry); 2940 2941 retval = -EFSCORRUPTED; 2942 if (le32_to_cpu(de->inode) != inode->i_ino) 2943 goto end_rmdir; 2944 2945 retval = -ENOTEMPTY; 2946 if (!ext4_empty_dir(inode)) 2947 goto end_rmdir; 2948 2949 handle = ext4_journal_start(dir, EXT4_HT_DIR, 2950 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 2951 if (IS_ERR(handle)) { 2952 retval = PTR_ERR(handle); 2953 handle = NULL; 2954 goto end_rmdir; 2955 } 2956 2957 if (IS_DIRSYNC(dir)) 2958 ext4_handle_sync(handle); 2959 2960 retval = ext4_delete_entry(handle, dir, de, bh); 2961 if (retval) 2962 goto end_rmdir; 2963 if (!EXT4_DIR_LINK_EMPTY(inode)) 2964 ext4_warning_inode(inode, 2965 "empty directory '%.*s' has too many links (%u)", 2966 dentry->d_name.len, dentry->d_name.name, 2967 inode->i_nlink); 2968 inode->i_version++; 2969 clear_nlink(inode); 2970 /* There's no need to set i_disksize: the fact that i_nlink is 2971 * zero will ensure that the right thing happens during any 2972 * recovery. */ 2973 inode->i_size = 0; 2974 ext4_orphan_add(handle, inode); 2975 inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); 2976 ext4_mark_inode_dirty(handle, inode); 2977 ext4_dec_count(handle, dir); 2978 ext4_update_dx_flag(dir); 2979 ext4_mark_inode_dirty(handle, dir); 2980 2981 end_rmdir: 2982 brelse(bh); 2983 if (handle) 2984 ext4_journal_stop(handle); 2985 return retval; 2986 } 2987 2988 static int ext4_unlink(struct inode *dir, struct dentry *dentry) 2989 { 2990 int retval; 2991 struct inode *inode; 2992 struct buffer_head *bh; 2993 struct ext4_dir_entry_2 *de; 2994 handle_t *handle = NULL; 2995 2996 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 2997 return -EIO; 2998 2999 trace_ext4_unlink_enter(dir, dentry); 3000 /* Initialize quotas before so that eventual writes go 3001 * in separate transaction */ 3002 retval = dquot_initialize(dir); 3003 if (retval) 3004 return retval; 3005 retval = dquot_initialize(d_inode(dentry)); 3006 if (retval) 3007 return retval; 3008 3009 retval = -ENOENT; 3010 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 3011 if (IS_ERR(bh)) 3012 return PTR_ERR(bh); 3013 if (!bh) 3014 goto end_unlink; 3015 3016 inode = d_inode(dentry); 3017 3018 retval = -EFSCORRUPTED; 3019 if (le32_to_cpu(de->inode) != inode->i_ino) 3020 goto end_unlink; 3021 3022 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3023 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 3024 if (IS_ERR(handle)) { 3025 retval = PTR_ERR(handle); 3026 handle = NULL; 3027 goto end_unlink; 3028 } 3029 3030 if (IS_DIRSYNC(dir)) 3031 ext4_handle_sync(handle); 3032 3033 if (inode->i_nlink == 0) { 3034 ext4_warning_inode(inode, "Deleting file '%.*s' with no links", 3035 dentry->d_name.len, dentry->d_name.name); 3036 set_nlink(inode, 1); 3037 } 3038 retval = ext4_delete_entry(handle, dir, de, bh); 3039 if (retval) 3040 goto end_unlink; 3041 dir->i_ctime = dir->i_mtime = current_time(dir); 3042 ext4_update_dx_flag(dir); 3043 ext4_mark_inode_dirty(handle, dir); 3044 drop_nlink(inode); 3045 if (!inode->i_nlink) 3046 ext4_orphan_add(handle, inode); 3047 inode->i_ctime = current_time(inode); 3048 ext4_mark_inode_dirty(handle, inode); 3049 3050 end_unlink: 3051 brelse(bh); 3052 if (handle) 3053 ext4_journal_stop(handle); 3054 trace_ext4_unlink_exit(dentry, retval); 3055 return retval; 3056 } 3057 3058 static int ext4_symlink(struct inode *dir, 3059 struct dentry *dentry, const char *symname) 3060 { 3061 handle_t *handle; 3062 struct inode *inode; 3063 int err, len = strlen(symname); 3064 int credits; 3065 bool encryption_required; 3066 struct fscrypt_str disk_link; 3067 struct fscrypt_symlink_data *sd = NULL; 3068 3069 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3070 return -EIO; 3071 3072 disk_link.len = len + 1; 3073 disk_link.name = (char *) symname; 3074 3075 encryption_required = (ext4_encrypted_inode(dir) || 3076 DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb))); 3077 if (encryption_required) { 3078 err = fscrypt_get_encryption_info(dir); 3079 if (err) 3080 return err; 3081 if (!fscrypt_has_encryption_key(dir)) 3082 return -ENOKEY; 3083 disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + 3084 sizeof(struct fscrypt_symlink_data)); 3085 sd = kzalloc(disk_link.len, GFP_KERNEL); 3086 if (!sd) 3087 return -ENOMEM; 3088 } 3089 3090 if (disk_link.len > dir->i_sb->s_blocksize) { 3091 err = -ENAMETOOLONG; 3092 goto err_free_sd; 3093 } 3094 3095 err = dquot_initialize(dir); 3096 if (err) 3097 goto err_free_sd; 3098 3099 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3100 /* 3101 * For non-fast symlinks, we just allocate inode and put it on 3102 * orphan list in the first transaction => we need bitmap, 3103 * group descriptor, sb, inode block, quota blocks, and 3104 * possibly selinux xattr blocks. 3105 */ 3106 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 3107 EXT4_XATTR_TRANS_BLOCKS; 3108 } else { 3109 /* 3110 * Fast symlink. We have to add entry to directory 3111 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), 3112 * allocate new inode (bitmap, group descriptor, inode block, 3113 * quota blocks, sb is already counted in previous macros). 3114 */ 3115 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3116 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3; 3117 } 3118 3119 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO, 3120 &dentry->d_name, 0, NULL, 3121 EXT4_HT_DIR, credits); 3122 handle = ext4_journal_current_handle(); 3123 if (IS_ERR(inode)) { 3124 if (handle) 3125 ext4_journal_stop(handle); 3126 err = PTR_ERR(inode); 3127 goto err_free_sd; 3128 } 3129 3130 if (encryption_required) { 3131 struct qstr istr; 3132 struct fscrypt_str ostr = 3133 FSTR_INIT(sd->encrypted_path, disk_link.len); 3134 3135 istr.name = (const unsigned char *) symname; 3136 istr.len = len; 3137 err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); 3138 if (err) 3139 goto err_drop_inode; 3140 sd->len = cpu_to_le16(ostr.len); 3141 disk_link.name = (char *) sd; 3142 inode->i_op = &ext4_encrypted_symlink_inode_operations; 3143 } 3144 3145 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3146 if (!encryption_required) 3147 inode->i_op = &ext4_symlink_inode_operations; 3148 inode_nohighmem(inode); 3149 ext4_set_aops(inode); 3150 /* 3151 * We cannot call page_symlink() with transaction started 3152 * because it calls into ext4_write_begin() which can wait 3153 * for transaction commit if we are running out of space 3154 * and thus we deadlock. So we have to stop transaction now 3155 * and restart it when symlink contents is written. 3156 * 3157 * To keep fs consistent in case of crash, we have to put inode 3158 * to orphan list in the mean time. 3159 */ 3160 drop_nlink(inode); 3161 err = ext4_orphan_add(handle, inode); 3162 ext4_journal_stop(handle); 3163 handle = NULL; 3164 if (err) 3165 goto err_drop_inode; 3166 err = __page_symlink(inode, disk_link.name, disk_link.len, 1); 3167 if (err) 3168 goto err_drop_inode; 3169 /* 3170 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS 3171 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified 3172 */ 3173 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3174 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3175 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); 3176 if (IS_ERR(handle)) { 3177 err = PTR_ERR(handle); 3178 handle = NULL; 3179 goto err_drop_inode; 3180 } 3181 set_nlink(inode, 1); 3182 err = ext4_orphan_del(handle, inode); 3183 if (err) 3184 goto err_drop_inode; 3185 } else { 3186 /* clear the extent format for fast symlink */ 3187 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); 3188 if (!encryption_required) { 3189 inode->i_op = &ext4_fast_symlink_inode_operations; 3190 inode->i_link = (char *)&EXT4_I(inode)->i_data; 3191 } 3192 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name, 3193 disk_link.len); 3194 inode->i_size = disk_link.len - 1; 3195 } 3196 EXT4_I(inode)->i_disksize = inode->i_size; 3197 err = ext4_add_nondir(handle, dentry, inode); 3198 if (!err && IS_DIRSYNC(dir)) 3199 ext4_handle_sync(handle); 3200 3201 if (handle) 3202 ext4_journal_stop(handle); 3203 kfree(sd); 3204 return err; 3205 err_drop_inode: 3206 if (handle) 3207 ext4_journal_stop(handle); 3208 clear_nlink(inode); 3209 unlock_new_inode(inode); 3210 iput(inode); 3211 err_free_sd: 3212 kfree(sd); 3213 return err; 3214 } 3215 3216 static int ext4_link(struct dentry *old_dentry, 3217 struct inode *dir, struct dentry *dentry) 3218 { 3219 handle_t *handle; 3220 struct inode *inode = d_inode(old_dentry); 3221 int err, retries = 0; 3222 3223 if (inode->i_nlink >= EXT4_LINK_MAX) 3224 return -EMLINK; 3225 if (ext4_encrypted_inode(dir) && 3226 !fscrypt_has_permitted_context(dir, inode)) 3227 return -EPERM; 3228 3229 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) && 3230 (!projid_eq(EXT4_I(dir)->i_projid, 3231 EXT4_I(old_dentry->d_inode)->i_projid))) 3232 return -EXDEV; 3233 3234 err = dquot_initialize(dir); 3235 if (err) 3236 return err; 3237 3238 retry: 3239 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3240 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3241 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1); 3242 if (IS_ERR(handle)) 3243 return PTR_ERR(handle); 3244 3245 if (IS_DIRSYNC(dir)) 3246 ext4_handle_sync(handle); 3247 3248 inode->i_ctime = current_time(inode); 3249 ext4_inc_count(handle, inode); 3250 ihold(inode); 3251 3252 err = ext4_add_entry(handle, dentry, inode); 3253 if (!err) { 3254 ext4_mark_inode_dirty(handle, inode); 3255 /* this can happen only for tmpfile being 3256 * linked the first time 3257 */ 3258 if (inode->i_nlink == 1) 3259 ext4_orphan_del(handle, inode); 3260 d_instantiate(dentry, inode); 3261 } else { 3262 drop_nlink(inode); 3263 iput(inode); 3264 } 3265 ext4_journal_stop(handle); 3266 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 3267 goto retry; 3268 return err; 3269 } 3270 3271 3272 /* 3273 * Try to find buffer head where contains the parent block. 3274 * It should be the inode block if it is inlined or the 1st block 3275 * if it is a normal dir. 3276 */ 3277 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, 3278 struct inode *inode, 3279 int *retval, 3280 struct ext4_dir_entry_2 **parent_de, 3281 int *inlined) 3282 { 3283 struct buffer_head *bh; 3284 3285 if (!ext4_has_inline_data(inode)) { 3286 bh = ext4_read_dirblock(inode, 0, EITHER); 3287 if (IS_ERR(bh)) { 3288 *retval = PTR_ERR(bh); 3289 return NULL; 3290 } 3291 *parent_de = ext4_next_entry( 3292 (struct ext4_dir_entry_2 *)bh->b_data, 3293 inode->i_sb->s_blocksize); 3294 return bh; 3295 } 3296 3297 *inlined = 1; 3298 return ext4_get_first_inline_block(inode, parent_de, retval); 3299 } 3300 3301 struct ext4_renament { 3302 struct inode *dir; 3303 struct dentry *dentry; 3304 struct inode *inode; 3305 bool is_dir; 3306 int dir_nlink_delta; 3307 3308 /* entry for "dentry" */ 3309 struct buffer_head *bh; 3310 struct ext4_dir_entry_2 *de; 3311 int inlined; 3312 3313 /* entry for ".." in inode if it's a directory */ 3314 struct buffer_head *dir_bh; 3315 struct ext4_dir_entry_2 *parent_de; 3316 int dir_inlined; 3317 }; 3318 3319 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) 3320 { 3321 int retval; 3322 3323 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, 3324 &retval, &ent->parent_de, 3325 &ent->dir_inlined); 3326 if (!ent->dir_bh) 3327 return retval; 3328 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) 3329 return -EFSCORRUPTED; 3330 BUFFER_TRACE(ent->dir_bh, "get_write_access"); 3331 return ext4_journal_get_write_access(handle, ent->dir_bh); 3332 } 3333 3334 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, 3335 unsigned dir_ino) 3336 { 3337 int retval; 3338 3339 ent->parent_de->inode = cpu_to_le32(dir_ino); 3340 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); 3341 if (!ent->dir_inlined) { 3342 if (is_dx(ent->inode)) { 3343 retval = ext4_handle_dirty_dx_node(handle, 3344 ent->inode, 3345 ent->dir_bh); 3346 } else { 3347 retval = ext4_handle_dirty_dirent_node(handle, 3348 ent->inode, 3349 ent->dir_bh); 3350 } 3351 } else { 3352 retval = ext4_mark_inode_dirty(handle, ent->inode); 3353 } 3354 if (retval) { 3355 ext4_std_error(ent->dir->i_sb, retval); 3356 return retval; 3357 } 3358 return 0; 3359 } 3360 3361 static int ext4_setent(handle_t *handle, struct ext4_renament *ent, 3362 unsigned ino, unsigned file_type) 3363 { 3364 int retval; 3365 3366 BUFFER_TRACE(ent->bh, "get write access"); 3367 retval = ext4_journal_get_write_access(handle, ent->bh); 3368 if (retval) 3369 return retval; 3370 ent->de->inode = cpu_to_le32(ino); 3371 if (ext4_has_feature_filetype(ent->dir->i_sb)) 3372 ent->de->file_type = file_type; 3373 ent->dir->i_version++; 3374 ent->dir->i_ctime = ent->dir->i_mtime = 3375 current_time(ent->dir); 3376 ext4_mark_inode_dirty(handle, ent->dir); 3377 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); 3378 if (!ent->inlined) { 3379 retval = ext4_handle_dirty_dirent_node(handle, 3380 ent->dir, ent->bh); 3381 if (unlikely(retval)) { 3382 ext4_std_error(ent->dir->i_sb, retval); 3383 return retval; 3384 } 3385 } 3386 brelse(ent->bh); 3387 ent->bh = NULL; 3388 3389 return 0; 3390 } 3391 3392 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, 3393 const struct qstr *d_name) 3394 { 3395 int retval = -ENOENT; 3396 struct buffer_head *bh; 3397 struct ext4_dir_entry_2 *de; 3398 3399 bh = ext4_find_entry(dir, d_name, &de, NULL); 3400 if (IS_ERR(bh)) 3401 return PTR_ERR(bh); 3402 if (bh) { 3403 retval = ext4_delete_entry(handle, dir, de, bh); 3404 brelse(bh); 3405 } 3406 return retval; 3407 } 3408 3409 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent, 3410 int force_reread) 3411 { 3412 int retval; 3413 /* 3414 * ent->de could have moved from under us during htree split, so make 3415 * sure that we are deleting the right entry. We might also be pointing 3416 * to a stale entry in the unused part of ent->bh so just checking inum 3417 * and the name isn't enough. 3418 */ 3419 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || 3420 ent->de->name_len != ent->dentry->d_name.len || 3421 strncmp(ent->de->name, ent->dentry->d_name.name, 3422 ent->de->name_len) || 3423 force_reread) { 3424 retval = ext4_find_delete_entry(handle, ent->dir, 3425 &ent->dentry->d_name); 3426 } else { 3427 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); 3428 if (retval == -ENOENT) { 3429 retval = ext4_find_delete_entry(handle, ent->dir, 3430 &ent->dentry->d_name); 3431 } 3432 } 3433 3434 if (retval) { 3435 ext4_warning_inode(ent->dir, 3436 "Deleting old file: nlink %d, error=%d", 3437 ent->dir->i_nlink, retval); 3438 } 3439 } 3440 3441 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) 3442 { 3443 if (ent->dir_nlink_delta) { 3444 if (ent->dir_nlink_delta == -1) 3445 ext4_dec_count(handle, ent->dir); 3446 else 3447 ext4_inc_count(handle, ent->dir); 3448 ext4_mark_inode_dirty(handle, ent->dir); 3449 } 3450 } 3451 3452 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, 3453 int credits, handle_t **h) 3454 { 3455 struct inode *wh; 3456 handle_t *handle; 3457 int retries = 0; 3458 3459 /* 3460 * for inode block, sb block, group summaries, 3461 * and inode bitmap 3462 */ 3463 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + 3464 EXT4_XATTR_TRANS_BLOCKS + 4); 3465 retry: 3466 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, 3467 &ent->dentry->d_name, 0, NULL, 3468 EXT4_HT_DIR, credits); 3469 3470 handle = ext4_journal_current_handle(); 3471 if (IS_ERR(wh)) { 3472 if (handle) 3473 ext4_journal_stop(handle); 3474 if (PTR_ERR(wh) == -ENOSPC && 3475 ext4_should_retry_alloc(ent->dir->i_sb, &retries)) 3476 goto retry; 3477 } else { 3478 *h = handle; 3479 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); 3480 wh->i_op = &ext4_special_inode_operations; 3481 } 3482 return wh; 3483 } 3484 3485 /* 3486 * Anybody can rename anything with this: the permission checks are left to the 3487 * higher-level routines. 3488 * 3489 * n.b. old_{dentry,inode) refers to the source dentry/inode 3490 * while new_{dentry,inode) refers to the destination dentry/inode 3491 * This comes from rename(const char *oldpath, const char *newpath) 3492 */ 3493 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, 3494 struct inode *new_dir, struct dentry *new_dentry, 3495 unsigned int flags) 3496 { 3497 handle_t *handle = NULL; 3498 struct ext4_renament old = { 3499 .dir = old_dir, 3500 .dentry = old_dentry, 3501 .inode = d_inode(old_dentry), 3502 }; 3503 struct ext4_renament new = { 3504 .dir = new_dir, 3505 .dentry = new_dentry, 3506 .inode = d_inode(new_dentry), 3507 }; 3508 int force_reread; 3509 int retval; 3510 struct inode *whiteout = NULL; 3511 int credits; 3512 u8 old_file_type; 3513 3514 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && 3515 (!projid_eq(EXT4_I(new_dir)->i_projid, 3516 EXT4_I(old_dentry->d_inode)->i_projid))) 3517 return -EXDEV; 3518 3519 if ((ext4_encrypted_inode(old_dir) && 3520 !fscrypt_has_encryption_key(old_dir)) || 3521 (ext4_encrypted_inode(new_dir) && 3522 !fscrypt_has_encryption_key(new_dir))) 3523 return -ENOKEY; 3524 3525 retval = dquot_initialize(old.dir); 3526 if (retval) 3527 return retval; 3528 retval = dquot_initialize(new.dir); 3529 if (retval) 3530 return retval; 3531 3532 /* Initialize quotas before so that eventual writes go 3533 * in separate transaction */ 3534 if (new.inode) { 3535 retval = dquot_initialize(new.inode); 3536 if (retval) 3537 return retval; 3538 } 3539 3540 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); 3541 if (IS_ERR(old.bh)) 3542 return PTR_ERR(old.bh); 3543 /* 3544 * Check for inode number is _not_ due to possible IO errors. 3545 * We might rmdir the source, keep it as pwd of some process 3546 * and merrily kill the link to whatever was created under the 3547 * same name. Goodbye sticky bit ;-< 3548 */ 3549 retval = -ENOENT; 3550 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3551 goto end_rename; 3552 3553 if ((old.dir != new.dir) && 3554 ext4_encrypted_inode(new.dir) && 3555 !fscrypt_has_permitted_context(new.dir, old.inode)) { 3556 retval = -EPERM; 3557 goto end_rename; 3558 } 3559 3560 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3561 &new.de, &new.inlined); 3562 if (IS_ERR(new.bh)) { 3563 retval = PTR_ERR(new.bh); 3564 new.bh = NULL; 3565 goto end_rename; 3566 } 3567 if (new.bh) { 3568 if (!new.inode) { 3569 brelse(new.bh); 3570 new.bh = NULL; 3571 } 3572 } 3573 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) 3574 ext4_alloc_da_blocks(old.inode); 3575 3576 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3577 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); 3578 if (!(flags & RENAME_WHITEOUT)) { 3579 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); 3580 if (IS_ERR(handle)) { 3581 retval = PTR_ERR(handle); 3582 handle = NULL; 3583 goto end_rename; 3584 } 3585 } else { 3586 whiteout = ext4_whiteout_for_rename(&old, credits, &handle); 3587 if (IS_ERR(whiteout)) { 3588 retval = PTR_ERR(whiteout); 3589 whiteout = NULL; 3590 goto end_rename; 3591 } 3592 } 3593 3594 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3595 ext4_handle_sync(handle); 3596 3597 if (S_ISDIR(old.inode->i_mode)) { 3598 if (new.inode) { 3599 retval = -ENOTEMPTY; 3600 if (!ext4_empty_dir(new.inode)) 3601 goto end_rename; 3602 } else { 3603 retval = -EMLINK; 3604 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) 3605 goto end_rename; 3606 } 3607 retval = ext4_rename_dir_prepare(handle, &old); 3608 if (retval) 3609 goto end_rename; 3610 } 3611 /* 3612 * If we're renaming a file within an inline_data dir and adding or 3613 * setting the new dirent causes a conversion from inline_data to 3614 * extents/blockmap, we need to force the dirent delete code to 3615 * re-read the directory, or else we end up trying to delete a dirent 3616 * from what is now the extent tree root (or a block map). 3617 */ 3618 force_reread = (new.dir->i_ino == old.dir->i_ino && 3619 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); 3620 3621 old_file_type = old.de->file_type; 3622 if (whiteout) { 3623 /* 3624 * Do this before adding a new entry, so the old entry is sure 3625 * to be still pointing to the valid old entry. 3626 */ 3627 retval = ext4_setent(handle, &old, whiteout->i_ino, 3628 EXT4_FT_CHRDEV); 3629 if (retval) 3630 goto end_rename; 3631 ext4_mark_inode_dirty(handle, whiteout); 3632 } 3633 if (!new.bh) { 3634 retval = ext4_add_entry(handle, new.dentry, old.inode); 3635 if (retval) 3636 goto end_rename; 3637 } else { 3638 retval = ext4_setent(handle, &new, 3639 old.inode->i_ino, old_file_type); 3640 if (retval) 3641 goto end_rename; 3642 } 3643 if (force_reread) 3644 force_reread = !ext4_test_inode_flag(new.dir, 3645 EXT4_INODE_INLINE_DATA); 3646 3647 /* 3648 * Like most other Unix systems, set the ctime for inodes on a 3649 * rename. 3650 */ 3651 old.inode->i_ctime = current_time(old.inode); 3652 ext4_mark_inode_dirty(handle, old.inode); 3653 3654 if (!whiteout) { 3655 /* 3656 * ok, that's it 3657 */ 3658 ext4_rename_delete(handle, &old, force_reread); 3659 } 3660 3661 if (new.inode) { 3662 ext4_dec_count(handle, new.inode); 3663 new.inode->i_ctime = current_time(new.inode); 3664 } 3665 old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir); 3666 ext4_update_dx_flag(old.dir); 3667 if (old.dir_bh) { 3668 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3669 if (retval) 3670 goto end_rename; 3671 3672 ext4_dec_count(handle, old.dir); 3673 if (new.inode) { 3674 /* checked ext4_empty_dir above, can't have another 3675 * parent, ext4_dec_count() won't work for many-linked 3676 * dirs */ 3677 clear_nlink(new.inode); 3678 } else { 3679 ext4_inc_count(handle, new.dir); 3680 ext4_update_dx_flag(new.dir); 3681 ext4_mark_inode_dirty(handle, new.dir); 3682 } 3683 } 3684 ext4_mark_inode_dirty(handle, old.dir); 3685 if (new.inode) { 3686 ext4_mark_inode_dirty(handle, new.inode); 3687 if (!new.inode->i_nlink) 3688 ext4_orphan_add(handle, new.inode); 3689 } 3690 retval = 0; 3691 3692 end_rename: 3693 brelse(old.dir_bh); 3694 brelse(old.bh); 3695 brelse(new.bh); 3696 if (whiteout) { 3697 if (retval) 3698 drop_nlink(whiteout); 3699 unlock_new_inode(whiteout); 3700 iput(whiteout); 3701 } 3702 if (handle) 3703 ext4_journal_stop(handle); 3704 return retval; 3705 } 3706 3707 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, 3708 struct inode *new_dir, struct dentry *new_dentry) 3709 { 3710 handle_t *handle = NULL; 3711 struct ext4_renament old = { 3712 .dir = old_dir, 3713 .dentry = old_dentry, 3714 .inode = d_inode(old_dentry), 3715 }; 3716 struct ext4_renament new = { 3717 .dir = new_dir, 3718 .dentry = new_dentry, 3719 .inode = d_inode(new_dentry), 3720 }; 3721 u8 new_file_type; 3722 int retval; 3723 struct timespec ctime; 3724 3725 if ((ext4_encrypted_inode(old_dir) && 3726 !fscrypt_has_encryption_key(old_dir)) || 3727 (ext4_encrypted_inode(new_dir) && 3728 !fscrypt_has_encryption_key(new_dir))) 3729 return -ENOKEY; 3730 3731 if ((ext4_encrypted_inode(old_dir) || 3732 ext4_encrypted_inode(new_dir)) && 3733 (old_dir != new_dir) && 3734 (!fscrypt_has_permitted_context(new_dir, old.inode) || 3735 !fscrypt_has_permitted_context(old_dir, new.inode))) 3736 return -EPERM; 3737 3738 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) && 3739 !projid_eq(EXT4_I(new_dir)->i_projid, 3740 EXT4_I(old_dentry->d_inode)->i_projid)) || 3741 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) && 3742 !projid_eq(EXT4_I(old_dir)->i_projid, 3743 EXT4_I(new_dentry->d_inode)->i_projid))) 3744 return -EXDEV; 3745 3746 retval = dquot_initialize(old.dir); 3747 if (retval) 3748 return retval; 3749 retval = dquot_initialize(new.dir); 3750 if (retval) 3751 return retval; 3752 3753 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, 3754 &old.de, &old.inlined); 3755 if (IS_ERR(old.bh)) 3756 return PTR_ERR(old.bh); 3757 /* 3758 * Check for inode number is _not_ due to possible IO errors. 3759 * We might rmdir the source, keep it as pwd of some process 3760 * and merrily kill the link to whatever was created under the 3761 * same name. Goodbye sticky bit ;-< 3762 */ 3763 retval = -ENOENT; 3764 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3765 goto end_rename; 3766 3767 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3768 &new.de, &new.inlined); 3769 if (IS_ERR(new.bh)) { 3770 retval = PTR_ERR(new.bh); 3771 new.bh = NULL; 3772 goto end_rename; 3773 } 3774 3775 /* RENAME_EXCHANGE case: old *and* new must both exist */ 3776 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) 3777 goto end_rename; 3778 3779 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, 3780 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3781 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); 3782 if (IS_ERR(handle)) { 3783 retval = PTR_ERR(handle); 3784 handle = NULL; 3785 goto end_rename; 3786 } 3787 3788 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3789 ext4_handle_sync(handle); 3790 3791 if (S_ISDIR(old.inode->i_mode)) { 3792 old.is_dir = true; 3793 retval = ext4_rename_dir_prepare(handle, &old); 3794 if (retval) 3795 goto end_rename; 3796 } 3797 if (S_ISDIR(new.inode->i_mode)) { 3798 new.is_dir = true; 3799 retval = ext4_rename_dir_prepare(handle, &new); 3800 if (retval) 3801 goto end_rename; 3802 } 3803 3804 /* 3805 * Other than the special case of overwriting a directory, parents' 3806 * nlink only needs to be modified if this is a cross directory rename. 3807 */ 3808 if (old.dir != new.dir && old.is_dir != new.is_dir) { 3809 old.dir_nlink_delta = old.is_dir ? -1 : 1; 3810 new.dir_nlink_delta = -old.dir_nlink_delta; 3811 retval = -EMLINK; 3812 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || 3813 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) 3814 goto end_rename; 3815 } 3816 3817 new_file_type = new.de->file_type; 3818 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); 3819 if (retval) 3820 goto end_rename; 3821 3822 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); 3823 if (retval) 3824 goto end_rename; 3825 3826 /* 3827 * Like most other Unix systems, set the ctime for inodes on a 3828 * rename. 3829 */ 3830 ctime = current_time(old.inode); 3831 old.inode->i_ctime = ctime; 3832 new.inode->i_ctime = ctime; 3833 ext4_mark_inode_dirty(handle, old.inode); 3834 ext4_mark_inode_dirty(handle, new.inode); 3835 3836 if (old.dir_bh) { 3837 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3838 if (retval) 3839 goto end_rename; 3840 } 3841 if (new.dir_bh) { 3842 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); 3843 if (retval) 3844 goto end_rename; 3845 } 3846 ext4_update_dir_count(handle, &old); 3847 ext4_update_dir_count(handle, &new); 3848 retval = 0; 3849 3850 end_rename: 3851 brelse(old.dir_bh); 3852 brelse(new.dir_bh); 3853 brelse(old.bh); 3854 brelse(new.bh); 3855 if (handle) 3856 ext4_journal_stop(handle); 3857 return retval; 3858 } 3859 3860 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, 3861 struct inode *new_dir, struct dentry *new_dentry, 3862 unsigned int flags) 3863 { 3864 if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb)))) 3865 return -EIO; 3866 3867 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 3868 return -EINVAL; 3869 3870 if (flags & RENAME_EXCHANGE) { 3871 return ext4_cross_rename(old_dir, old_dentry, 3872 new_dir, new_dentry); 3873 } 3874 3875 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 3876 } 3877 3878 /* 3879 * directories can handle most operations... 3880 */ 3881 const struct inode_operations ext4_dir_inode_operations = { 3882 .create = ext4_create, 3883 .lookup = ext4_lookup, 3884 .link = ext4_link, 3885 .unlink = ext4_unlink, 3886 .symlink = ext4_symlink, 3887 .mkdir = ext4_mkdir, 3888 .rmdir = ext4_rmdir, 3889 .mknod = ext4_mknod, 3890 .tmpfile = ext4_tmpfile, 3891 .rename = ext4_rename2, 3892 .setattr = ext4_setattr, 3893 .getattr = ext4_getattr, 3894 .listxattr = ext4_listxattr, 3895 .get_acl = ext4_get_acl, 3896 .set_acl = ext4_set_acl, 3897 .fiemap = ext4_fiemap, 3898 }; 3899 3900 const struct inode_operations ext4_special_inode_operations = { 3901 .setattr = ext4_setattr, 3902 .getattr = ext4_getattr, 3903 .listxattr = ext4_listxattr, 3904 .get_acl = ext4_get_acl, 3905 .set_acl = ext4_set_acl, 3906 }; 3907