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 <linux/iversion.h> 38 #include <linux/unicode.h> 39 #include "ext4.h" 40 #include "ext4_jbd2.h" 41 42 #include "xattr.h" 43 #include "acl.h" 44 45 #include <trace/events/ext4.h> 46 /* 47 * define how far ahead to read directories while searching them. 48 */ 49 #define NAMEI_RA_CHUNKS 2 50 #define NAMEI_RA_BLOCKS 4 51 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) 52 53 static struct buffer_head *ext4_append(handle_t *handle, 54 struct inode *inode, 55 ext4_lblk_t *block) 56 { 57 struct buffer_head *bh; 58 int err; 59 60 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb && 61 ((inode->i_size >> 10) >= 62 EXT4_SB(inode->i_sb)->s_max_dir_size_kb))) 63 return ERR_PTR(-ENOSPC); 64 65 *block = inode->i_size >> inode->i_sb->s_blocksize_bits; 66 67 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE); 68 if (IS_ERR(bh)) 69 return bh; 70 inode->i_size += inode->i_sb->s_blocksize; 71 EXT4_I(inode)->i_disksize = inode->i_size; 72 BUFFER_TRACE(bh, "get_write_access"); 73 err = ext4_journal_get_write_access(handle, bh); 74 if (err) { 75 brelse(bh); 76 ext4_std_error(inode->i_sb, err); 77 return ERR_PTR(err); 78 } 79 return bh; 80 } 81 82 static int ext4_dx_csum_verify(struct inode *inode, 83 struct ext4_dir_entry *dirent); 84 85 /* 86 * Hints to ext4_read_dirblock regarding whether we expect a directory 87 * block being read to be an index block, or a block containing 88 * directory entries (and if the latter, whether it was found via a 89 * logical block in an htree index block). This is used to control 90 * what sort of sanity checkinig ext4_read_dirblock() will do on the 91 * directory block read from the storage device. EITHER will means 92 * the caller doesn't know what kind of directory block will be read, 93 * so no specific verification will be done. 94 */ 95 typedef enum { 96 EITHER, INDEX, DIRENT, DIRENT_HTREE 97 } dirblock_type_t; 98 99 #define ext4_read_dirblock(inode, block, type) \ 100 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__) 101 102 static struct buffer_head *__ext4_read_dirblock(struct inode *inode, 103 ext4_lblk_t block, 104 dirblock_type_t type, 105 const char *func, 106 unsigned int line) 107 { 108 struct buffer_head *bh; 109 struct ext4_dir_entry *dirent; 110 int is_dx_block = 0; 111 112 if (ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_EIO)) 113 bh = ERR_PTR(-EIO); 114 else 115 bh = ext4_bread(NULL, inode, block, 0); 116 if (IS_ERR(bh)) { 117 __ext4_warning(inode->i_sb, func, line, 118 "inode #%lu: lblock %lu: comm %s: " 119 "error %ld reading directory block", 120 inode->i_ino, (unsigned long)block, 121 current->comm, PTR_ERR(bh)); 122 123 return bh; 124 } 125 if (!bh && (type == INDEX || type == DIRENT_HTREE)) { 126 ext4_error_inode(inode, func, line, block, 127 "Directory hole found for htree %s block", 128 (type == INDEX) ? "index" : "leaf"); 129 return ERR_PTR(-EFSCORRUPTED); 130 } 131 if (!bh) 132 return NULL; 133 dirent = (struct ext4_dir_entry *) bh->b_data; 134 /* Determine whether or not we have an index block */ 135 if (is_dx(inode)) { 136 if (block == 0) 137 is_dx_block = 1; 138 else if (ext4_rec_len_from_disk(dirent->rec_len, 139 inode->i_sb->s_blocksize) == 140 inode->i_sb->s_blocksize) 141 is_dx_block = 1; 142 } 143 if (!is_dx_block && type == INDEX) { 144 ext4_error_inode(inode, func, line, block, 145 "directory leaf block found instead of index block"); 146 brelse(bh); 147 return ERR_PTR(-EFSCORRUPTED); 148 } 149 if (!ext4_has_metadata_csum(inode->i_sb) || 150 buffer_verified(bh)) 151 return bh; 152 153 /* 154 * An empty leaf block can get mistaken for a index block; for 155 * this reason, we can only check the index checksum when the 156 * caller is sure it should be an index block. 157 */ 158 if (is_dx_block && type == INDEX) { 159 if (ext4_dx_csum_verify(inode, dirent) && 160 !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC)) 161 set_buffer_verified(bh); 162 else { 163 ext4_set_errno(inode->i_sb, EFSBADCRC); 164 ext4_error_inode(inode, func, line, block, 165 "Directory index failed checksum"); 166 brelse(bh); 167 return ERR_PTR(-EFSBADCRC); 168 } 169 } 170 if (!is_dx_block) { 171 if (ext4_dirblock_csum_verify(inode, bh) && 172 !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC)) 173 set_buffer_verified(bh); 174 else { 175 ext4_set_errno(inode->i_sb, EFSBADCRC); 176 ext4_error_inode(inode, func, line, block, 177 "Directory block failed checksum"); 178 brelse(bh); 179 return ERR_PTR(-EFSBADCRC); 180 } 181 } 182 return bh; 183 } 184 185 #ifndef assert 186 #define assert(test) J_ASSERT(test) 187 #endif 188 189 #ifdef DX_DEBUG 190 #define dxtrace(command) command 191 #else 192 #define dxtrace(command) 193 #endif 194 195 struct fake_dirent 196 { 197 __le32 inode; 198 __le16 rec_len; 199 u8 name_len; 200 u8 file_type; 201 }; 202 203 struct dx_countlimit 204 { 205 __le16 limit; 206 __le16 count; 207 }; 208 209 struct dx_entry 210 { 211 __le32 hash; 212 __le32 block; 213 }; 214 215 /* 216 * dx_root_info is laid out so that if it should somehow get overlaid by a 217 * dirent the two low bits of the hash version will be zero. Therefore, the 218 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 219 */ 220 221 struct dx_root 222 { 223 struct fake_dirent dot; 224 char dot_name[4]; 225 struct fake_dirent dotdot; 226 char dotdot_name[4]; 227 struct dx_root_info 228 { 229 __le32 reserved_zero; 230 u8 hash_version; 231 u8 info_length; /* 8 */ 232 u8 indirect_levels; 233 u8 unused_flags; 234 } 235 info; 236 struct dx_entry entries[0]; 237 }; 238 239 struct dx_node 240 { 241 struct fake_dirent fake; 242 struct dx_entry entries[0]; 243 }; 244 245 246 struct dx_frame 247 { 248 struct buffer_head *bh; 249 struct dx_entry *entries; 250 struct dx_entry *at; 251 }; 252 253 struct dx_map_entry 254 { 255 u32 hash; 256 u16 offs; 257 u16 size; 258 }; 259 260 /* 261 * This goes at the end of each htree block. 262 */ 263 struct dx_tail { 264 u32 dt_reserved; 265 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */ 266 }; 267 268 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry); 269 static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value); 270 static inline unsigned dx_get_hash(struct dx_entry *entry); 271 static void dx_set_hash(struct dx_entry *entry, unsigned value); 272 static unsigned dx_get_count(struct dx_entry *entries); 273 static unsigned dx_get_limit(struct dx_entry *entries); 274 static void dx_set_count(struct dx_entry *entries, unsigned value); 275 static void dx_set_limit(struct dx_entry *entries, unsigned value); 276 static unsigned dx_root_limit(struct inode *dir, unsigned infosize); 277 static unsigned dx_node_limit(struct inode *dir); 278 static struct dx_frame *dx_probe(struct ext4_filename *fname, 279 struct inode *dir, 280 struct dx_hash_info *hinfo, 281 struct dx_frame *frame); 282 static void dx_release(struct dx_frame *frames); 283 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 284 unsigned blocksize, struct dx_hash_info *hinfo, 285 struct dx_map_entry map[]); 286 static void dx_sort_map(struct dx_map_entry *map, unsigned count); 287 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to, 288 struct dx_map_entry *offsets, int count, unsigned blocksize); 289 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize); 290 static void dx_insert_block(struct dx_frame *frame, 291 u32 hash, ext4_lblk_t block); 292 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 293 struct dx_frame *frame, 294 struct dx_frame *frames, 295 __u32 *start_hash); 296 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 297 struct ext4_filename *fname, 298 struct ext4_dir_entry_2 **res_dir); 299 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 300 struct inode *dir, struct inode *inode); 301 302 /* checksumming functions */ 303 void ext4_initialize_dirent_tail(struct buffer_head *bh, 304 unsigned int blocksize) 305 { 306 struct ext4_dir_entry_tail *t = EXT4_DIRENT_TAIL(bh->b_data, blocksize); 307 308 memset(t, 0, sizeof(struct ext4_dir_entry_tail)); 309 t->det_rec_len = ext4_rec_len_to_disk( 310 sizeof(struct ext4_dir_entry_tail), blocksize); 311 t->det_reserved_ft = EXT4_FT_DIR_CSUM; 312 } 313 314 /* Walk through a dirent block to find a checksum "dirent" at the tail */ 315 static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode, 316 struct buffer_head *bh) 317 { 318 struct ext4_dir_entry_tail *t; 319 320 #ifdef PARANOID 321 struct ext4_dir_entry *d, *top; 322 323 d = (struct ext4_dir_entry *)bh->b_data; 324 top = (struct ext4_dir_entry *)(bh->b_data + 325 (EXT4_BLOCK_SIZE(inode->i_sb) - 326 sizeof(struct ext4_dir_entry_tail))); 327 while (d < top && d->rec_len) 328 d = (struct ext4_dir_entry *)(((void *)d) + 329 le16_to_cpu(d->rec_len)); 330 331 if (d != top) 332 return NULL; 333 334 t = (struct ext4_dir_entry_tail *)d; 335 #else 336 t = EXT4_DIRENT_TAIL(bh->b_data, EXT4_BLOCK_SIZE(inode->i_sb)); 337 #endif 338 339 if (t->det_reserved_zero1 || 340 le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) || 341 t->det_reserved_zero2 || 342 t->det_reserved_ft != EXT4_FT_DIR_CSUM) 343 return NULL; 344 345 return t; 346 } 347 348 static __le32 ext4_dirblock_csum(struct inode *inode, void *dirent, int size) 349 { 350 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 351 struct ext4_inode_info *ei = EXT4_I(inode); 352 __u32 csum; 353 354 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 355 return cpu_to_le32(csum); 356 } 357 358 #define warn_no_space_for_csum(inode) \ 359 __warn_no_space_for_csum((inode), __func__, __LINE__) 360 361 static void __warn_no_space_for_csum(struct inode *inode, const char *func, 362 unsigned int line) 363 { 364 __ext4_warning_inode(inode, func, line, 365 "No space for directory leaf checksum. Please run e2fsck -D."); 366 } 367 368 int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh) 369 { 370 struct ext4_dir_entry_tail *t; 371 372 if (!ext4_has_metadata_csum(inode->i_sb)) 373 return 1; 374 375 t = get_dirent_tail(inode, bh); 376 if (!t) { 377 warn_no_space_for_csum(inode); 378 return 0; 379 } 380 381 if (t->det_checksum != ext4_dirblock_csum(inode, bh->b_data, 382 (char *)t - bh->b_data)) 383 return 0; 384 385 return 1; 386 } 387 388 static void ext4_dirblock_csum_set(struct inode *inode, 389 struct buffer_head *bh) 390 { 391 struct ext4_dir_entry_tail *t; 392 393 if (!ext4_has_metadata_csum(inode->i_sb)) 394 return; 395 396 t = get_dirent_tail(inode, bh); 397 if (!t) { 398 warn_no_space_for_csum(inode); 399 return; 400 } 401 402 t->det_checksum = ext4_dirblock_csum(inode, bh->b_data, 403 (char *)t - bh->b_data); 404 } 405 406 int ext4_handle_dirty_dirblock(handle_t *handle, 407 struct inode *inode, 408 struct buffer_head *bh) 409 { 410 ext4_dirblock_csum_set(inode, bh); 411 return ext4_handle_dirty_metadata(handle, inode, bh); 412 } 413 414 static struct dx_countlimit *get_dx_countlimit(struct inode *inode, 415 struct ext4_dir_entry *dirent, 416 int *offset) 417 { 418 struct ext4_dir_entry *dp; 419 struct dx_root_info *root; 420 int count_offset; 421 422 if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb)) 423 count_offset = 8; 424 else if (le16_to_cpu(dirent->rec_len) == 12) { 425 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12); 426 if (le16_to_cpu(dp->rec_len) != 427 EXT4_BLOCK_SIZE(inode->i_sb) - 12) 428 return NULL; 429 root = (struct dx_root_info *)(((void *)dp + 12)); 430 if (root->reserved_zero || 431 root->info_length != sizeof(struct dx_root_info)) 432 return NULL; 433 count_offset = 32; 434 } else 435 return NULL; 436 437 if (offset) 438 *offset = count_offset; 439 return (struct dx_countlimit *)(((void *)dirent) + count_offset); 440 } 441 442 static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent, 443 int count_offset, int count, struct dx_tail *t) 444 { 445 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 446 struct ext4_inode_info *ei = EXT4_I(inode); 447 __u32 csum; 448 int size; 449 __u32 dummy_csum = 0; 450 int offset = offsetof(struct dx_tail, dt_checksum); 451 452 size = count_offset + (count * sizeof(struct dx_entry)); 453 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size); 454 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset); 455 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); 456 457 return cpu_to_le32(csum); 458 } 459 460 static int ext4_dx_csum_verify(struct inode *inode, 461 struct ext4_dir_entry *dirent) 462 { 463 struct dx_countlimit *c; 464 struct dx_tail *t; 465 int count_offset, limit, count; 466 467 if (!ext4_has_metadata_csum(inode->i_sb)) 468 return 1; 469 470 c = get_dx_countlimit(inode, dirent, &count_offset); 471 if (!c) { 472 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 473 return 0; 474 } 475 limit = le16_to_cpu(c->limit); 476 count = le16_to_cpu(c->count); 477 if (count_offset + (limit * sizeof(struct dx_entry)) > 478 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 479 warn_no_space_for_csum(inode); 480 return 0; 481 } 482 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 483 484 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset, 485 count, t)) 486 return 0; 487 return 1; 488 } 489 490 static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent) 491 { 492 struct dx_countlimit *c; 493 struct dx_tail *t; 494 int count_offset, limit, count; 495 496 if (!ext4_has_metadata_csum(inode->i_sb)) 497 return; 498 499 c = get_dx_countlimit(inode, dirent, &count_offset); 500 if (!c) { 501 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D."); 502 return; 503 } 504 limit = le16_to_cpu(c->limit); 505 count = le16_to_cpu(c->count); 506 if (count_offset + (limit * sizeof(struct dx_entry)) > 507 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) { 508 warn_no_space_for_csum(inode); 509 return; 510 } 511 t = (struct dx_tail *)(((struct dx_entry *)c) + limit); 512 513 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t); 514 } 515 516 static inline int ext4_handle_dirty_dx_node(handle_t *handle, 517 struct inode *inode, 518 struct buffer_head *bh) 519 { 520 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data); 521 return ext4_handle_dirty_metadata(handle, inode, bh); 522 } 523 524 /* 525 * p is at least 6 bytes before the end of page 526 */ 527 static inline struct ext4_dir_entry_2 * 528 ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize) 529 { 530 return (struct ext4_dir_entry_2 *)((char *)p + 531 ext4_rec_len_from_disk(p->rec_len, blocksize)); 532 } 533 534 /* 535 * Future: use high four bits of block for coalesce-on-delete flags 536 * Mask them off for now. 537 */ 538 539 static inline ext4_lblk_t dx_get_block(struct dx_entry *entry) 540 { 541 return le32_to_cpu(entry->block) & 0x0fffffff; 542 } 543 544 static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value) 545 { 546 entry->block = cpu_to_le32(value); 547 } 548 549 static inline unsigned dx_get_hash(struct dx_entry *entry) 550 { 551 return le32_to_cpu(entry->hash); 552 } 553 554 static inline void dx_set_hash(struct dx_entry *entry, unsigned value) 555 { 556 entry->hash = cpu_to_le32(value); 557 } 558 559 static inline unsigned dx_get_count(struct dx_entry *entries) 560 { 561 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 562 } 563 564 static inline unsigned dx_get_limit(struct dx_entry *entries) 565 { 566 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 567 } 568 569 static inline void dx_set_count(struct dx_entry *entries, unsigned value) 570 { 571 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 572 } 573 574 static inline void dx_set_limit(struct dx_entry *entries, unsigned value) 575 { 576 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 577 } 578 579 static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize) 580 { 581 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) - 582 EXT4_DIR_REC_LEN(2) - infosize; 583 584 if (ext4_has_metadata_csum(dir->i_sb)) 585 entry_space -= sizeof(struct dx_tail); 586 return entry_space / sizeof(struct dx_entry); 587 } 588 589 static inline unsigned dx_node_limit(struct inode *dir) 590 { 591 unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0); 592 593 if (ext4_has_metadata_csum(dir->i_sb)) 594 entry_space -= sizeof(struct dx_tail); 595 return entry_space / sizeof(struct dx_entry); 596 } 597 598 /* 599 * Debug 600 */ 601 #ifdef DX_DEBUG 602 static void dx_show_index(char * label, struct dx_entry *entries) 603 { 604 int i, n = dx_get_count (entries); 605 printk(KERN_DEBUG "%s index", label); 606 for (i = 0; i < n; i++) { 607 printk(KERN_CONT " %x->%lu", 608 i ? dx_get_hash(entries + i) : 0, 609 (unsigned long)dx_get_block(entries + i)); 610 } 611 printk(KERN_CONT "\n"); 612 } 613 614 struct stats 615 { 616 unsigned names; 617 unsigned space; 618 unsigned bcount; 619 }; 620 621 static struct stats dx_show_leaf(struct inode *dir, 622 struct dx_hash_info *hinfo, 623 struct ext4_dir_entry_2 *de, 624 int size, int show_names) 625 { 626 unsigned names = 0, space = 0; 627 char *base = (char *) de; 628 struct dx_hash_info h = *hinfo; 629 630 printk("names: "); 631 while ((char *) de < base + size) 632 { 633 if (de->inode) 634 { 635 if (show_names) 636 { 637 #ifdef CONFIG_FS_ENCRYPTION 638 int len; 639 char *name; 640 struct fscrypt_str fname_crypto_str = 641 FSTR_INIT(NULL, 0); 642 int res = 0; 643 644 name = de->name; 645 len = de->name_len; 646 if (IS_ENCRYPTED(dir)) 647 res = fscrypt_get_encryption_info(dir); 648 if (res) { 649 printk(KERN_WARNING "Error setting up" 650 " fname crypto: %d\n", res); 651 } 652 if (!fscrypt_has_encryption_key(dir)) { 653 /* Directory is not encrypted */ 654 ext4fs_dirhash(dir, de->name, 655 de->name_len, &h); 656 printk("%*.s:(U)%x.%u ", len, 657 name, h.hash, 658 (unsigned) ((char *) de 659 - base)); 660 } else { 661 struct fscrypt_str de_name = 662 FSTR_INIT(name, len); 663 664 /* Directory is encrypted */ 665 res = fscrypt_fname_alloc_buffer( 666 dir, len, 667 &fname_crypto_str); 668 if (res) 669 printk(KERN_WARNING "Error " 670 "allocating crypto " 671 "buffer--skipping " 672 "crypto\n"); 673 res = fscrypt_fname_disk_to_usr(dir, 674 0, 0, &de_name, 675 &fname_crypto_str); 676 if (res) { 677 printk(KERN_WARNING "Error " 678 "converting filename " 679 "from disk to usr" 680 "\n"); 681 name = "??"; 682 len = 2; 683 } else { 684 name = fname_crypto_str.name; 685 len = fname_crypto_str.len; 686 } 687 ext4fs_dirhash(dir, de->name, 688 de->name_len, &h); 689 printk("%*.s:(E)%x.%u ", len, name, 690 h.hash, (unsigned) ((char *) de 691 - base)); 692 fscrypt_fname_free_buffer( 693 &fname_crypto_str); 694 } 695 #else 696 int len = de->name_len; 697 char *name = de->name; 698 ext4fs_dirhash(dir, de->name, de->name_len, &h); 699 printk("%*.s:%x.%u ", len, name, h.hash, 700 (unsigned) ((char *) de - base)); 701 #endif 702 } 703 space += EXT4_DIR_REC_LEN(de->name_len); 704 names++; 705 } 706 de = ext4_next_entry(de, size); 707 } 708 printk(KERN_CONT "(%i)\n", names); 709 return (struct stats) { names, space, 1 }; 710 } 711 712 struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 713 struct dx_entry *entries, int levels) 714 { 715 unsigned blocksize = dir->i_sb->s_blocksize; 716 unsigned count = dx_get_count(entries), names = 0, space = 0, i; 717 unsigned bcount = 0; 718 struct buffer_head *bh; 719 printk("%i indexed blocks...\n", count); 720 for (i = 0; i < count; i++, entries++) 721 { 722 ext4_lblk_t block = dx_get_block(entries); 723 ext4_lblk_t hash = i ? dx_get_hash(entries): 0; 724 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 725 struct stats stats; 726 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 727 bh = ext4_bread(NULL,dir, block, 0); 728 if (!bh || IS_ERR(bh)) 729 continue; 730 stats = levels? 731 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 732 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) 733 bh->b_data, blocksize, 0); 734 names += stats.names; 735 space += stats.space; 736 bcount += stats.bcount; 737 brelse(bh); 738 } 739 if (bcount) 740 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n", 741 levels ? "" : " ", names, space/bcount, 742 (space/bcount)*100/blocksize); 743 return (struct stats) { names, space, bcount}; 744 } 745 #endif /* DX_DEBUG */ 746 747 /* 748 * Probe for a directory leaf block to search. 749 * 750 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 751 * error in the directory index, and the caller should fall back to 752 * searching the directory normally. The callers of dx_probe **MUST** 753 * check for this error code, and make sure it never gets reflected 754 * back to userspace. 755 */ 756 static struct dx_frame * 757 dx_probe(struct ext4_filename *fname, struct inode *dir, 758 struct dx_hash_info *hinfo, struct dx_frame *frame_in) 759 { 760 unsigned count, indirect; 761 struct dx_entry *at, *entries, *p, *q, *m; 762 struct dx_root *root; 763 struct dx_frame *frame = frame_in; 764 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR); 765 u32 hash; 766 767 memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0])); 768 frame->bh = ext4_read_dirblock(dir, 0, INDEX); 769 if (IS_ERR(frame->bh)) 770 return (struct dx_frame *) frame->bh; 771 772 root = (struct dx_root *) frame->bh->b_data; 773 if (root->info.hash_version != DX_HASH_TEA && 774 root->info.hash_version != DX_HASH_HALF_MD4 && 775 root->info.hash_version != DX_HASH_LEGACY) { 776 ext4_warning_inode(dir, "Unrecognised inode hash code %u", 777 root->info.hash_version); 778 goto fail; 779 } 780 if (fname) 781 hinfo = &fname->hinfo; 782 hinfo->hash_version = root->info.hash_version; 783 if (hinfo->hash_version <= DX_HASH_TEA) 784 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 785 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; 786 if (fname && fname_name(fname)) 787 ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), hinfo); 788 hash = hinfo->hash; 789 790 if (root->info.unused_flags & 1) { 791 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x", 792 root->info.unused_flags); 793 goto fail; 794 } 795 796 indirect = root->info.indirect_levels; 797 if (indirect >= ext4_dir_htree_level(dir->i_sb)) { 798 ext4_warning(dir->i_sb, 799 "Directory (ino: %lu) htree depth %#06x exceed" 800 "supported value", dir->i_ino, 801 ext4_dir_htree_level(dir->i_sb)); 802 if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) { 803 ext4_warning(dir->i_sb, "Enable large directory " 804 "feature to access it"); 805 } 806 goto fail; 807 } 808 809 entries = (struct dx_entry *)(((char *)&root->info) + 810 root->info.info_length); 811 812 if (dx_get_limit(entries) != dx_root_limit(dir, 813 root->info.info_length)) { 814 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u", 815 dx_get_limit(entries), 816 dx_root_limit(dir, root->info.info_length)); 817 goto fail; 818 } 819 820 dxtrace(printk("Look up %x", hash)); 821 while (1) { 822 count = dx_get_count(entries); 823 if (!count || count > dx_get_limit(entries)) { 824 ext4_warning_inode(dir, 825 "dx entry: count %u beyond limit %u", 826 count, dx_get_limit(entries)); 827 goto fail; 828 } 829 830 p = entries + 1; 831 q = entries + count - 1; 832 while (p <= q) { 833 m = p + (q - p) / 2; 834 dxtrace(printk(KERN_CONT ".")); 835 if (dx_get_hash(m) > hash) 836 q = m - 1; 837 else 838 p = m + 1; 839 } 840 841 if (0) { // linear search cross check 842 unsigned n = count - 1; 843 at = entries; 844 while (n--) 845 { 846 dxtrace(printk(KERN_CONT ",")); 847 if (dx_get_hash(++at) > hash) 848 { 849 at--; 850 break; 851 } 852 } 853 assert (at == p - 1); 854 } 855 856 at = p - 1; 857 dxtrace(printk(KERN_CONT " %x->%u\n", 858 at == entries ? 0 : dx_get_hash(at), 859 dx_get_block(at))); 860 frame->entries = entries; 861 frame->at = at; 862 if (!indirect--) 863 return frame; 864 frame++; 865 frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX); 866 if (IS_ERR(frame->bh)) { 867 ret_err = (struct dx_frame *) frame->bh; 868 frame->bh = NULL; 869 goto fail; 870 } 871 entries = ((struct dx_node *) frame->bh->b_data)->entries; 872 873 if (dx_get_limit(entries) != dx_node_limit(dir)) { 874 ext4_warning_inode(dir, 875 "dx entry: limit %u != node limit %u", 876 dx_get_limit(entries), dx_node_limit(dir)); 877 goto fail; 878 } 879 } 880 fail: 881 while (frame >= frame_in) { 882 brelse(frame->bh); 883 frame--; 884 } 885 886 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR)) 887 ext4_warning_inode(dir, 888 "Corrupt directory, running e2fsck is recommended"); 889 return ret_err; 890 } 891 892 static void dx_release(struct dx_frame *frames) 893 { 894 struct dx_root_info *info; 895 int i; 896 unsigned int indirect_levels; 897 898 if (frames[0].bh == NULL) 899 return; 900 901 info = &((struct dx_root *)frames[0].bh->b_data)->info; 902 /* save local copy, "info" may be freed after brelse() */ 903 indirect_levels = info->indirect_levels; 904 for (i = 0; i <= indirect_levels; i++) { 905 if (frames[i].bh == NULL) 906 break; 907 brelse(frames[i].bh); 908 frames[i].bh = NULL; 909 } 910 } 911 912 /* 913 * This function increments the frame pointer to search the next leaf 914 * block, and reads in the necessary intervening nodes if the search 915 * should be necessary. Whether or not the search is necessary is 916 * controlled by the hash parameter. If the hash value is even, then 917 * the search is only continued if the next block starts with that 918 * hash value. This is used if we are searching for a specific file. 919 * 920 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 921 * 922 * This function returns 1 if the caller should continue to search, 923 * or 0 if it should not. If there is an error reading one of the 924 * index blocks, it will a negative error code. 925 * 926 * If start_hash is non-null, it will be filled in with the starting 927 * hash of the next page. 928 */ 929 static int ext4_htree_next_block(struct inode *dir, __u32 hash, 930 struct dx_frame *frame, 931 struct dx_frame *frames, 932 __u32 *start_hash) 933 { 934 struct dx_frame *p; 935 struct buffer_head *bh; 936 int num_frames = 0; 937 __u32 bhash; 938 939 p = frame; 940 /* 941 * Find the next leaf page by incrementing the frame pointer. 942 * If we run out of entries in the interior node, loop around and 943 * increment pointer in the parent node. When we break out of 944 * this loop, num_frames indicates the number of interior 945 * nodes need to be read. 946 */ 947 while (1) { 948 if (++(p->at) < p->entries + dx_get_count(p->entries)) 949 break; 950 if (p == frames) 951 return 0; 952 num_frames++; 953 p--; 954 } 955 956 /* 957 * If the hash is 1, then continue only if the next page has a 958 * continuation hash of any value. This is used for readdir 959 * handling. Otherwise, check to see if the hash matches the 960 * desired contiuation hash. If it doesn't, return since 961 * there's no point to read in the successive index pages. 962 */ 963 bhash = dx_get_hash(p->at); 964 if (start_hash) 965 *start_hash = bhash; 966 if ((hash & 1) == 0) { 967 if ((bhash & ~1) != hash) 968 return 0; 969 } 970 /* 971 * If the hash is HASH_NB_ALWAYS, we always go to the next 972 * block so no check is necessary 973 */ 974 while (num_frames--) { 975 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX); 976 if (IS_ERR(bh)) 977 return PTR_ERR(bh); 978 p++; 979 brelse(p->bh); 980 p->bh = bh; 981 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 982 } 983 return 1; 984 } 985 986 987 /* 988 * This function fills a red-black tree with information from a 989 * directory block. It returns the number directory entries loaded 990 * into the tree. If there is an error it is returned in err. 991 */ 992 static int htree_dirblock_to_tree(struct file *dir_file, 993 struct inode *dir, ext4_lblk_t block, 994 struct dx_hash_info *hinfo, 995 __u32 start_hash, __u32 start_minor_hash) 996 { 997 struct buffer_head *bh; 998 struct ext4_dir_entry_2 *de, *top; 999 int err = 0, count = 0; 1000 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str; 1001 1002 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", 1003 (unsigned long)block)); 1004 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE); 1005 if (IS_ERR(bh)) 1006 return PTR_ERR(bh); 1007 1008 de = (struct ext4_dir_entry_2 *) bh->b_data; 1009 top = (struct ext4_dir_entry_2 *) ((char *) de + 1010 dir->i_sb->s_blocksize - 1011 EXT4_DIR_REC_LEN(0)); 1012 /* Check if the directory is encrypted */ 1013 if (IS_ENCRYPTED(dir)) { 1014 err = fscrypt_get_encryption_info(dir); 1015 if (err < 0) { 1016 brelse(bh); 1017 return err; 1018 } 1019 err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN, 1020 &fname_crypto_str); 1021 if (err < 0) { 1022 brelse(bh); 1023 return err; 1024 } 1025 } 1026 1027 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { 1028 if (ext4_check_dir_entry(dir, NULL, de, bh, 1029 bh->b_data, bh->b_size, 1030 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb)) 1031 + ((char *)de - bh->b_data))) { 1032 /* silently ignore the rest of the block */ 1033 break; 1034 } 1035 ext4fs_dirhash(dir, de->name, de->name_len, hinfo); 1036 if ((hinfo->hash < start_hash) || 1037 ((hinfo->hash == start_hash) && 1038 (hinfo->minor_hash < start_minor_hash))) 1039 continue; 1040 if (de->inode == 0) 1041 continue; 1042 if (!IS_ENCRYPTED(dir)) { 1043 tmp_str.name = de->name; 1044 tmp_str.len = de->name_len; 1045 err = ext4_htree_store_dirent(dir_file, 1046 hinfo->hash, hinfo->minor_hash, de, 1047 &tmp_str); 1048 } else { 1049 int save_len = fname_crypto_str.len; 1050 struct fscrypt_str de_name = FSTR_INIT(de->name, 1051 de->name_len); 1052 1053 /* Directory is encrypted */ 1054 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash, 1055 hinfo->minor_hash, &de_name, 1056 &fname_crypto_str); 1057 if (err) { 1058 count = err; 1059 goto errout; 1060 } 1061 err = ext4_htree_store_dirent(dir_file, 1062 hinfo->hash, hinfo->minor_hash, de, 1063 &fname_crypto_str); 1064 fname_crypto_str.len = save_len; 1065 } 1066 if (err != 0) { 1067 count = err; 1068 goto errout; 1069 } 1070 count++; 1071 } 1072 errout: 1073 brelse(bh); 1074 fscrypt_fname_free_buffer(&fname_crypto_str); 1075 return count; 1076 } 1077 1078 1079 /* 1080 * This function fills a red-black tree with information from a 1081 * directory. We start scanning the directory in hash order, starting 1082 * at start_hash and start_minor_hash. 1083 * 1084 * This function returns the number of entries inserted into the tree, 1085 * or a negative error code. 1086 */ 1087 int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, 1088 __u32 start_minor_hash, __u32 *next_hash) 1089 { 1090 struct dx_hash_info hinfo; 1091 struct ext4_dir_entry_2 *de; 1092 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1093 struct inode *dir; 1094 ext4_lblk_t block; 1095 int count = 0; 1096 int ret, err; 1097 __u32 hashval; 1098 struct fscrypt_str tmp_str; 1099 1100 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n", 1101 start_hash, start_minor_hash)); 1102 dir = file_inode(dir_file); 1103 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) { 1104 hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 1105 if (hinfo.hash_version <= DX_HASH_TEA) 1106 hinfo.hash_version += 1107 EXT4_SB(dir->i_sb)->s_hash_unsigned; 1108 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 1109 if (ext4_has_inline_data(dir)) { 1110 int has_inline_data = 1; 1111 count = ext4_inlinedir_to_tree(dir_file, dir, 0, 1112 &hinfo, start_hash, 1113 start_minor_hash, 1114 &has_inline_data); 1115 if (has_inline_data) { 1116 *next_hash = ~0; 1117 return count; 1118 } 1119 } 1120 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 1121 start_hash, start_minor_hash); 1122 *next_hash = ~0; 1123 return count; 1124 } 1125 hinfo.hash = start_hash; 1126 hinfo.minor_hash = 0; 1127 frame = dx_probe(NULL, dir, &hinfo, frames); 1128 if (IS_ERR(frame)) 1129 return PTR_ERR(frame); 1130 1131 /* Add '.' and '..' from the htree header */ 1132 if (!start_hash && !start_minor_hash) { 1133 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1134 tmp_str.name = de->name; 1135 tmp_str.len = de->name_len; 1136 err = ext4_htree_store_dirent(dir_file, 0, 0, 1137 de, &tmp_str); 1138 if (err != 0) 1139 goto errout; 1140 count++; 1141 } 1142 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 1143 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; 1144 de = ext4_next_entry(de, dir->i_sb->s_blocksize); 1145 tmp_str.name = de->name; 1146 tmp_str.len = de->name_len; 1147 err = ext4_htree_store_dirent(dir_file, 2, 0, 1148 de, &tmp_str); 1149 if (err != 0) 1150 goto errout; 1151 count++; 1152 } 1153 1154 while (1) { 1155 if (fatal_signal_pending(current)) { 1156 err = -ERESTARTSYS; 1157 goto errout; 1158 } 1159 cond_resched(); 1160 block = dx_get_block(frame->at); 1161 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 1162 start_hash, start_minor_hash); 1163 if (ret < 0) { 1164 err = ret; 1165 goto errout; 1166 } 1167 count += ret; 1168 hashval = ~0; 1169 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS, 1170 frame, frames, &hashval); 1171 *next_hash = hashval; 1172 if (ret < 0) { 1173 err = ret; 1174 goto errout; 1175 } 1176 /* 1177 * Stop if: (a) there are no more entries, or 1178 * (b) we have inserted at least one entry and the 1179 * next hash value is not a continuation 1180 */ 1181 if ((ret == 0) || 1182 (count && ((hashval & 1) == 0))) 1183 break; 1184 } 1185 dx_release(frames); 1186 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, " 1187 "next hash: %x\n", count, *next_hash)); 1188 return count; 1189 errout: 1190 dx_release(frames); 1191 return (err); 1192 } 1193 1194 static inline int search_dirblock(struct buffer_head *bh, 1195 struct inode *dir, 1196 struct ext4_filename *fname, 1197 unsigned int offset, 1198 struct ext4_dir_entry_2 **res_dir) 1199 { 1200 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir, 1201 fname, offset, res_dir); 1202 } 1203 1204 /* 1205 * Directory block splitting, compacting 1206 */ 1207 1208 /* 1209 * Create map of hash values, offsets, and sizes, stored at end of block. 1210 * Returns number of entries mapped. 1211 */ 1212 static int dx_make_map(struct inode *dir, struct ext4_dir_entry_2 *de, 1213 unsigned blocksize, struct dx_hash_info *hinfo, 1214 struct dx_map_entry *map_tail) 1215 { 1216 int count = 0; 1217 char *base = (char *) de; 1218 struct dx_hash_info h = *hinfo; 1219 1220 while ((char *) de < base + blocksize) { 1221 if (de->name_len && de->inode) { 1222 ext4fs_dirhash(dir, de->name, de->name_len, &h); 1223 map_tail--; 1224 map_tail->hash = h.hash; 1225 map_tail->offs = ((char *) de - base)>>2; 1226 map_tail->size = le16_to_cpu(de->rec_len); 1227 count++; 1228 cond_resched(); 1229 } 1230 /* XXX: do we need to check rec_len == 0 case? -Chris */ 1231 de = ext4_next_entry(de, blocksize); 1232 } 1233 return count; 1234 } 1235 1236 /* Sort map by hash value */ 1237 static void dx_sort_map (struct dx_map_entry *map, unsigned count) 1238 { 1239 struct dx_map_entry *p, *q, *top = map + count - 1; 1240 int more; 1241 /* Combsort until bubble sort doesn't suck */ 1242 while (count > 2) { 1243 count = count*10/13; 1244 if (count - 9 < 2) /* 9, 10 -> 11 */ 1245 count = 11; 1246 for (p = top, q = p - count; q >= map; p--, q--) 1247 if (p->hash < q->hash) 1248 swap(*p, *q); 1249 } 1250 /* Garden variety bubble sort */ 1251 do { 1252 more = 0; 1253 q = top; 1254 while (q-- > map) { 1255 if (q[1].hash >= q[0].hash) 1256 continue; 1257 swap(*(q+1), *q); 1258 more = 1; 1259 } 1260 } while(more); 1261 } 1262 1263 static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block) 1264 { 1265 struct dx_entry *entries = frame->entries; 1266 struct dx_entry *old = frame->at, *new = old + 1; 1267 int count = dx_get_count(entries); 1268 1269 assert(count < dx_get_limit(entries)); 1270 assert(old < entries + count); 1271 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 1272 dx_set_hash(new, hash); 1273 dx_set_block(new, block); 1274 dx_set_count(entries, count + 1); 1275 } 1276 1277 #ifdef CONFIG_UNICODE 1278 /* 1279 * Test whether a case-insensitive directory entry matches the filename 1280 * being searched for. If quick is set, assume the name being looked up 1281 * is already in the casefolded form. 1282 * 1283 * Returns: 0 if the directory entry matches, more than 0 if it 1284 * doesn't match or less than zero on error. 1285 */ 1286 int ext4_ci_compare(const struct inode *parent, const struct qstr *name, 1287 const struct qstr *entry, bool quick) 1288 { 1289 const struct ext4_sb_info *sbi = EXT4_SB(parent->i_sb); 1290 const struct unicode_map *um = sbi->s_encoding; 1291 int ret; 1292 1293 if (quick) 1294 ret = utf8_strncasecmp_folded(um, name, entry); 1295 else 1296 ret = utf8_strncasecmp(um, name, entry); 1297 1298 if (ret < 0) { 1299 /* Handle invalid character sequence as either an error 1300 * or as an opaque byte sequence. 1301 */ 1302 if (ext4_has_strict_mode(sbi)) 1303 return -EINVAL; 1304 1305 if (name->len != entry->len) 1306 return 1; 1307 1308 return !!memcmp(name->name, entry->name, name->len); 1309 } 1310 1311 return ret; 1312 } 1313 1314 void ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname, 1315 struct fscrypt_str *cf_name) 1316 { 1317 int len; 1318 1319 if (!IS_CASEFOLDED(dir) || !EXT4_SB(dir->i_sb)->s_encoding) { 1320 cf_name->name = NULL; 1321 return; 1322 } 1323 1324 cf_name->name = kmalloc(EXT4_NAME_LEN, GFP_NOFS); 1325 if (!cf_name->name) 1326 return; 1327 1328 len = utf8_casefold(EXT4_SB(dir->i_sb)->s_encoding, 1329 iname, cf_name->name, 1330 EXT4_NAME_LEN); 1331 if (len <= 0) { 1332 kfree(cf_name->name); 1333 cf_name->name = NULL; 1334 return; 1335 } 1336 cf_name->len = (unsigned) len; 1337 1338 } 1339 #endif 1340 1341 /* 1342 * Test whether a directory entry matches the filename being searched for. 1343 * 1344 * Return: %true if the directory entry matches, otherwise %false. 1345 */ 1346 static inline bool ext4_match(const struct inode *parent, 1347 const struct ext4_filename *fname, 1348 const struct ext4_dir_entry_2 *de) 1349 { 1350 struct fscrypt_name f; 1351 #ifdef CONFIG_UNICODE 1352 const struct qstr entry = {.name = de->name, .len = de->name_len}; 1353 #endif 1354 1355 if (!de->inode) 1356 return false; 1357 1358 f.usr_fname = fname->usr_fname; 1359 f.disk_name = fname->disk_name; 1360 #ifdef CONFIG_FS_ENCRYPTION 1361 f.crypto_buf = fname->crypto_buf; 1362 #endif 1363 1364 #ifdef CONFIG_UNICODE 1365 if (EXT4_SB(parent->i_sb)->s_encoding && IS_CASEFOLDED(parent)) { 1366 if (fname->cf_name.name) { 1367 struct qstr cf = {.name = fname->cf_name.name, 1368 .len = fname->cf_name.len}; 1369 return !ext4_ci_compare(parent, &cf, &entry, true); 1370 } 1371 return !ext4_ci_compare(parent, fname->usr_fname, &entry, 1372 false); 1373 } 1374 #endif 1375 1376 return fscrypt_match_name(&f, de->name, de->name_len); 1377 } 1378 1379 /* 1380 * Returns 0 if not found, -1 on failure, and 1 on success 1381 */ 1382 int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size, 1383 struct inode *dir, struct ext4_filename *fname, 1384 unsigned int offset, struct ext4_dir_entry_2 **res_dir) 1385 { 1386 struct ext4_dir_entry_2 * de; 1387 char * dlimit; 1388 int de_len; 1389 1390 de = (struct ext4_dir_entry_2 *)search_buf; 1391 dlimit = search_buf + buf_size; 1392 while ((char *) de < dlimit) { 1393 /* this code is executed quadratically often */ 1394 /* do minimal checking `by hand' */ 1395 if ((char *) de + de->name_len <= dlimit && 1396 ext4_match(dir, fname, de)) { 1397 /* found a match - just to be sure, do 1398 * a full check */ 1399 if (ext4_check_dir_entry(dir, NULL, de, bh, bh->b_data, 1400 bh->b_size, offset)) 1401 return -1; 1402 *res_dir = de; 1403 return 1; 1404 } 1405 /* prevent looping on a bad block */ 1406 de_len = ext4_rec_len_from_disk(de->rec_len, 1407 dir->i_sb->s_blocksize); 1408 if (de_len <= 0) 1409 return -1; 1410 offset += de_len; 1411 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); 1412 } 1413 return 0; 1414 } 1415 1416 static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block, 1417 struct ext4_dir_entry *de) 1418 { 1419 struct super_block *sb = dir->i_sb; 1420 1421 if (!is_dx(dir)) 1422 return 0; 1423 if (block == 0) 1424 return 1; 1425 if (de->inode == 0 && 1426 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) == 1427 sb->s_blocksize) 1428 return 1; 1429 return 0; 1430 } 1431 1432 /* 1433 * __ext4_find_entry() 1434 * 1435 * finds an entry in the specified directory with the wanted name. It 1436 * returns the cache buffer in which the entry was found, and the entry 1437 * itself (as a parameter - res_dir). It does NOT read the inode of the 1438 * entry - you'll have to do that yourself if you want to. 1439 * 1440 * The returned buffer_head has ->b_count elevated. The caller is expected 1441 * to brelse() it when appropriate. 1442 */ 1443 static struct buffer_head *__ext4_find_entry(struct inode *dir, 1444 struct ext4_filename *fname, 1445 struct ext4_dir_entry_2 **res_dir, 1446 int *inlined) 1447 { 1448 struct super_block *sb; 1449 struct buffer_head *bh_use[NAMEI_RA_SIZE]; 1450 struct buffer_head *bh, *ret = NULL; 1451 ext4_lblk_t start, block; 1452 const u8 *name = fname->usr_fname->name; 1453 size_t ra_max = 0; /* Number of bh's in the readahead 1454 buffer, bh_use[] */ 1455 size_t ra_ptr = 0; /* Current index into readahead 1456 buffer */ 1457 ext4_lblk_t nblocks; 1458 int i, namelen, retval; 1459 1460 *res_dir = NULL; 1461 sb = dir->i_sb; 1462 namelen = fname->usr_fname->len; 1463 if (namelen > EXT4_NAME_LEN) 1464 return NULL; 1465 1466 if (ext4_has_inline_data(dir)) { 1467 int has_inline_data = 1; 1468 ret = ext4_find_inline_entry(dir, fname, res_dir, 1469 &has_inline_data); 1470 if (has_inline_data) { 1471 if (inlined) 1472 *inlined = 1; 1473 goto cleanup_and_exit; 1474 } 1475 } 1476 1477 if ((namelen <= 2) && (name[0] == '.') && 1478 (name[1] == '.' || name[1] == '\0')) { 1479 /* 1480 * "." or ".." will only be in the first block 1481 * NFS may look up ".."; "." should be handled by the VFS 1482 */ 1483 block = start = 0; 1484 nblocks = 1; 1485 goto restart; 1486 } 1487 if (is_dx(dir)) { 1488 ret = ext4_dx_find_entry(dir, fname, res_dir); 1489 /* 1490 * On success, or if the error was file not found, 1491 * return. Otherwise, fall back to doing a search the 1492 * old fashioned way. 1493 */ 1494 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR) 1495 goto cleanup_and_exit; 1496 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, " 1497 "falling back\n")); 1498 ret = NULL; 1499 } 1500 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1501 if (!nblocks) { 1502 ret = NULL; 1503 goto cleanup_and_exit; 1504 } 1505 start = EXT4_I(dir)->i_dir_start_lookup; 1506 if (start >= nblocks) 1507 start = 0; 1508 block = start; 1509 restart: 1510 do { 1511 /* 1512 * We deal with the read-ahead logic here. 1513 */ 1514 cond_resched(); 1515 if (ra_ptr >= ra_max) { 1516 /* Refill the readahead buffer */ 1517 ra_ptr = 0; 1518 if (block < start) 1519 ra_max = start - block; 1520 else 1521 ra_max = nblocks - block; 1522 ra_max = min(ra_max, ARRAY_SIZE(bh_use)); 1523 retval = ext4_bread_batch(dir, block, ra_max, 1524 false /* wait */, bh_use); 1525 if (retval) { 1526 ret = ERR_PTR(retval); 1527 ra_max = 0; 1528 goto cleanup_and_exit; 1529 } 1530 } 1531 if ((bh = bh_use[ra_ptr++]) == NULL) 1532 goto next; 1533 wait_on_buffer(bh); 1534 if (!buffer_uptodate(bh)) { 1535 ext4_set_errno(sb, EIO); 1536 EXT4_ERROR_INODE(dir, "reading directory lblock %lu", 1537 (unsigned long) block); 1538 brelse(bh); 1539 ret = ERR_PTR(-EIO); 1540 goto cleanup_and_exit; 1541 } 1542 if (!buffer_verified(bh) && 1543 !is_dx_internal_node(dir, block, 1544 (struct ext4_dir_entry *)bh->b_data) && 1545 !ext4_dirblock_csum_verify(dir, bh)) { 1546 ext4_set_errno(sb, EFSBADCRC); 1547 EXT4_ERROR_INODE(dir, "checksumming directory " 1548 "block %lu", (unsigned long)block); 1549 brelse(bh); 1550 ret = ERR_PTR(-EFSBADCRC); 1551 goto cleanup_and_exit; 1552 } 1553 set_buffer_verified(bh); 1554 i = search_dirblock(bh, dir, fname, 1555 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); 1556 if (i == 1) { 1557 EXT4_I(dir)->i_dir_start_lookup = block; 1558 ret = bh; 1559 goto cleanup_and_exit; 1560 } else { 1561 brelse(bh); 1562 if (i < 0) 1563 goto cleanup_and_exit; 1564 } 1565 next: 1566 if (++block >= nblocks) 1567 block = 0; 1568 } while (block != start); 1569 1570 /* 1571 * If the directory has grown while we were searching, then 1572 * search the last part of the directory before giving up. 1573 */ 1574 block = nblocks; 1575 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); 1576 if (block < nblocks) { 1577 start = 0; 1578 goto restart; 1579 } 1580 1581 cleanup_and_exit: 1582 /* Clean up the read-ahead blocks */ 1583 for (; ra_ptr < ra_max; ra_ptr++) 1584 brelse(bh_use[ra_ptr]); 1585 return ret; 1586 } 1587 1588 static struct buffer_head *ext4_find_entry(struct inode *dir, 1589 const struct qstr *d_name, 1590 struct ext4_dir_entry_2 **res_dir, 1591 int *inlined) 1592 { 1593 int err; 1594 struct ext4_filename fname; 1595 struct buffer_head *bh; 1596 1597 err = ext4_fname_setup_filename(dir, d_name, 1, &fname); 1598 if (err == -ENOENT) 1599 return NULL; 1600 if (err) 1601 return ERR_PTR(err); 1602 1603 bh = __ext4_find_entry(dir, &fname, res_dir, inlined); 1604 1605 ext4_fname_free_filename(&fname); 1606 return bh; 1607 } 1608 1609 static struct buffer_head *ext4_lookup_entry(struct inode *dir, 1610 struct dentry *dentry, 1611 struct ext4_dir_entry_2 **res_dir) 1612 { 1613 int err; 1614 struct ext4_filename fname; 1615 struct buffer_head *bh; 1616 1617 err = ext4_fname_prepare_lookup(dir, dentry, &fname); 1618 if (err == -ENOENT) 1619 return NULL; 1620 if (err) 1621 return ERR_PTR(err); 1622 1623 bh = __ext4_find_entry(dir, &fname, res_dir, NULL); 1624 1625 ext4_fname_free_filename(&fname); 1626 return bh; 1627 } 1628 1629 static struct buffer_head * ext4_dx_find_entry(struct inode *dir, 1630 struct ext4_filename *fname, 1631 struct ext4_dir_entry_2 **res_dir) 1632 { 1633 struct super_block * sb = dir->i_sb; 1634 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 1635 struct buffer_head *bh; 1636 ext4_lblk_t block; 1637 int retval; 1638 1639 #ifdef CONFIG_FS_ENCRYPTION 1640 *res_dir = NULL; 1641 #endif 1642 frame = dx_probe(fname, dir, NULL, frames); 1643 if (IS_ERR(frame)) 1644 return (struct buffer_head *) frame; 1645 do { 1646 block = dx_get_block(frame->at); 1647 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE); 1648 if (IS_ERR(bh)) 1649 goto errout; 1650 1651 retval = search_dirblock(bh, dir, fname, 1652 block << EXT4_BLOCK_SIZE_BITS(sb), 1653 res_dir); 1654 if (retval == 1) 1655 goto success; 1656 brelse(bh); 1657 if (retval == -1) { 1658 bh = ERR_PTR(ERR_BAD_DX_DIR); 1659 goto errout; 1660 } 1661 1662 /* Check to see if we should continue to search */ 1663 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame, 1664 frames, NULL); 1665 if (retval < 0) { 1666 ext4_warning_inode(dir, 1667 "error %d reading directory index block", 1668 retval); 1669 bh = ERR_PTR(retval); 1670 goto errout; 1671 } 1672 } while (retval == 1); 1673 1674 bh = NULL; 1675 errout: 1676 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name)); 1677 success: 1678 dx_release(frames); 1679 return bh; 1680 } 1681 1682 static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 1683 { 1684 struct inode *inode; 1685 struct ext4_dir_entry_2 *de; 1686 struct buffer_head *bh; 1687 1688 if (dentry->d_name.len > EXT4_NAME_LEN) 1689 return ERR_PTR(-ENAMETOOLONG); 1690 1691 bh = ext4_lookup_entry(dir, dentry, &de); 1692 if (IS_ERR(bh)) 1693 return ERR_CAST(bh); 1694 inode = NULL; 1695 if (bh) { 1696 __u32 ino = le32_to_cpu(de->inode); 1697 brelse(bh); 1698 if (!ext4_valid_inum(dir->i_sb, ino)) { 1699 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); 1700 return ERR_PTR(-EFSCORRUPTED); 1701 } 1702 if (unlikely(ino == dir->i_ino)) { 1703 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir", 1704 dentry); 1705 return ERR_PTR(-EFSCORRUPTED); 1706 } 1707 inode = ext4_iget(dir->i_sb, ino, EXT4_IGET_NORMAL); 1708 if (inode == ERR_PTR(-ESTALE)) { 1709 EXT4_ERROR_INODE(dir, 1710 "deleted inode referenced: %u", 1711 ino); 1712 return ERR_PTR(-EFSCORRUPTED); 1713 } 1714 if (!IS_ERR(inode) && IS_ENCRYPTED(dir) && 1715 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && 1716 !fscrypt_has_permitted_context(dir, inode)) { 1717 ext4_warning(inode->i_sb, 1718 "Inconsistent encryption contexts: %lu/%lu", 1719 dir->i_ino, inode->i_ino); 1720 iput(inode); 1721 return ERR_PTR(-EPERM); 1722 } 1723 } 1724 1725 #ifdef CONFIG_UNICODE 1726 if (!inode && IS_CASEFOLDED(dir)) { 1727 /* Eventually we want to call d_add_ci(dentry, NULL) 1728 * for negative dentries in the encoding case as 1729 * well. For now, prevent the negative dentry 1730 * from being cached. 1731 */ 1732 return NULL; 1733 } 1734 #endif 1735 return d_splice_alias(inode, dentry); 1736 } 1737 1738 1739 struct dentry *ext4_get_parent(struct dentry *child) 1740 { 1741 __u32 ino; 1742 static const struct qstr dotdot = QSTR_INIT("..", 2); 1743 struct ext4_dir_entry_2 * de; 1744 struct buffer_head *bh; 1745 1746 bh = ext4_find_entry(d_inode(child), &dotdot, &de, NULL); 1747 if (IS_ERR(bh)) 1748 return ERR_CAST(bh); 1749 if (!bh) 1750 return ERR_PTR(-ENOENT); 1751 ino = le32_to_cpu(de->inode); 1752 brelse(bh); 1753 1754 if (!ext4_valid_inum(child->d_sb, ino)) { 1755 EXT4_ERROR_INODE(d_inode(child), 1756 "bad parent inode number: %u", ino); 1757 return ERR_PTR(-EFSCORRUPTED); 1758 } 1759 1760 return d_obtain_alias(ext4_iget(child->d_sb, ino, EXT4_IGET_NORMAL)); 1761 } 1762 1763 /* 1764 * Move count entries from end of map between two memory locations. 1765 * Returns pointer to last entry moved. 1766 */ 1767 static struct ext4_dir_entry_2 * 1768 dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, 1769 unsigned blocksize) 1770 { 1771 unsigned rec_len = 0; 1772 1773 while (count--) { 1774 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) 1775 (from + (map->offs<<2)); 1776 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1777 memcpy (to, de, rec_len); 1778 ((struct ext4_dir_entry_2 *) to)->rec_len = 1779 ext4_rec_len_to_disk(rec_len, blocksize); 1780 de->inode = 0; 1781 map++; 1782 to += rec_len; 1783 } 1784 return (struct ext4_dir_entry_2 *) (to - rec_len); 1785 } 1786 1787 /* 1788 * Compact each dir entry in the range to the minimal rec_len. 1789 * Returns pointer to last entry in range. 1790 */ 1791 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) 1792 { 1793 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; 1794 unsigned rec_len = 0; 1795 1796 prev = to = de; 1797 while ((char*)de < base + blocksize) { 1798 next = ext4_next_entry(de, blocksize); 1799 if (de->inode && de->name_len) { 1800 rec_len = EXT4_DIR_REC_LEN(de->name_len); 1801 if (de > to) 1802 memmove(to, de, rec_len); 1803 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); 1804 prev = to; 1805 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); 1806 } 1807 de = next; 1808 } 1809 return prev; 1810 } 1811 1812 /* 1813 * Split a full leaf block to make room for a new dir entry. 1814 * Allocate a new block, and move entries so that they are approx. equally full. 1815 * Returns pointer to de in block into which the new entry will be inserted. 1816 */ 1817 static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1818 struct buffer_head **bh,struct dx_frame *frame, 1819 struct dx_hash_info *hinfo) 1820 { 1821 unsigned blocksize = dir->i_sb->s_blocksize; 1822 unsigned count, continued; 1823 struct buffer_head *bh2; 1824 ext4_lblk_t newblock; 1825 u32 hash2; 1826 struct dx_map_entry *map; 1827 char *data1 = (*bh)->b_data, *data2; 1828 unsigned split, move, size; 1829 struct ext4_dir_entry_2 *de = NULL, *de2; 1830 int csum_size = 0; 1831 int err = 0, i; 1832 1833 if (ext4_has_metadata_csum(dir->i_sb)) 1834 csum_size = sizeof(struct ext4_dir_entry_tail); 1835 1836 bh2 = ext4_append(handle, dir, &newblock); 1837 if (IS_ERR(bh2)) { 1838 brelse(*bh); 1839 *bh = NULL; 1840 return (struct ext4_dir_entry_2 *) bh2; 1841 } 1842 1843 BUFFER_TRACE(*bh, "get_write_access"); 1844 err = ext4_journal_get_write_access(handle, *bh); 1845 if (err) 1846 goto journal_error; 1847 1848 BUFFER_TRACE(frame->bh, "get_write_access"); 1849 err = ext4_journal_get_write_access(handle, frame->bh); 1850 if (err) 1851 goto journal_error; 1852 1853 data2 = bh2->b_data; 1854 1855 /* create map in the end of data2 block */ 1856 map = (struct dx_map_entry *) (data2 + blocksize); 1857 count = dx_make_map(dir, (struct ext4_dir_entry_2 *) data1, 1858 blocksize, hinfo, map); 1859 map -= count; 1860 dx_sort_map(map, count); 1861 /* Split the existing block in the middle, size-wise */ 1862 size = 0; 1863 move = 0; 1864 for (i = count-1; i >= 0; i--) { 1865 /* is more than half of this entry in 2nd half of the block? */ 1866 if (size + map[i].size/2 > blocksize/2) 1867 break; 1868 size += map[i].size; 1869 move++; 1870 } 1871 /* map index at which we will split */ 1872 split = count - move; 1873 hash2 = map[split].hash; 1874 continued = hash2 == map[split - 1].hash; 1875 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", 1876 (unsigned long)dx_get_block(frame->at), 1877 hash2, split, count-split)); 1878 1879 /* Fancy dance to stay within two buffers */ 1880 de2 = dx_move_dirents(data1, data2, map + split, count - split, 1881 blocksize); 1882 de = dx_pack_dirents(data1, blocksize); 1883 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) - 1884 (char *) de, 1885 blocksize); 1886 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - 1887 (char *) de2, 1888 blocksize); 1889 if (csum_size) { 1890 ext4_initialize_dirent_tail(*bh, blocksize); 1891 ext4_initialize_dirent_tail(bh2, blocksize); 1892 } 1893 1894 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1, 1895 blocksize, 1)); 1896 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2, 1897 blocksize, 1)); 1898 1899 /* Which block gets the new entry? */ 1900 if (hinfo->hash >= hash2) { 1901 swap(*bh, bh2); 1902 de = de2; 1903 } 1904 dx_insert_block(frame, hash2 + continued, newblock); 1905 err = ext4_handle_dirty_dirblock(handle, dir, bh2); 1906 if (err) 1907 goto journal_error; 1908 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 1909 if (err) 1910 goto journal_error; 1911 brelse(bh2); 1912 dxtrace(dx_show_index("frame", frame->entries)); 1913 return de; 1914 1915 journal_error: 1916 brelse(*bh); 1917 brelse(bh2); 1918 *bh = NULL; 1919 ext4_std_error(dir->i_sb, err); 1920 return ERR_PTR(err); 1921 } 1922 1923 int ext4_find_dest_de(struct inode *dir, struct inode *inode, 1924 struct buffer_head *bh, 1925 void *buf, int buf_size, 1926 struct ext4_filename *fname, 1927 struct ext4_dir_entry_2 **dest_de) 1928 { 1929 struct ext4_dir_entry_2 *de; 1930 unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname)); 1931 int nlen, rlen; 1932 unsigned int offset = 0; 1933 char *top; 1934 1935 de = (struct ext4_dir_entry_2 *)buf; 1936 top = buf + buf_size - reclen; 1937 while ((char *) de <= top) { 1938 if (ext4_check_dir_entry(dir, NULL, de, bh, 1939 buf, buf_size, offset)) 1940 return -EFSCORRUPTED; 1941 if (ext4_match(dir, fname, de)) 1942 return -EEXIST; 1943 nlen = EXT4_DIR_REC_LEN(de->name_len); 1944 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1945 if ((de->inode ? rlen - nlen : rlen) >= reclen) 1946 break; 1947 de = (struct ext4_dir_entry_2 *)((char *)de + rlen); 1948 offset += rlen; 1949 } 1950 if ((char *) de > top) 1951 return -ENOSPC; 1952 1953 *dest_de = de; 1954 return 0; 1955 } 1956 1957 void ext4_insert_dentry(struct inode *inode, 1958 struct ext4_dir_entry_2 *de, 1959 int buf_size, 1960 struct ext4_filename *fname) 1961 { 1962 1963 int nlen, rlen; 1964 1965 nlen = EXT4_DIR_REC_LEN(de->name_len); 1966 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); 1967 if (de->inode) { 1968 struct ext4_dir_entry_2 *de1 = 1969 (struct ext4_dir_entry_2 *)((char *)de + nlen); 1970 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); 1971 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); 1972 de = de1; 1973 } 1974 de->file_type = EXT4_FT_UNKNOWN; 1975 de->inode = cpu_to_le32(inode->i_ino); 1976 ext4_set_de_type(inode->i_sb, de, inode->i_mode); 1977 de->name_len = fname_len(fname); 1978 memcpy(de->name, fname_name(fname), fname_len(fname)); 1979 } 1980 1981 /* 1982 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1983 * it points to a directory entry which is guaranteed to be large 1984 * enough for new directory entry. If de is NULL, then 1985 * add_dirent_to_buf will attempt search the directory block for 1986 * space. It will return -ENOSPC if no space is available, and -EIO 1987 * and -EEXIST if directory entry already exists. 1988 */ 1989 static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname, 1990 struct inode *dir, 1991 struct inode *inode, struct ext4_dir_entry_2 *de, 1992 struct buffer_head *bh) 1993 { 1994 unsigned int blocksize = dir->i_sb->s_blocksize; 1995 int csum_size = 0; 1996 int err; 1997 1998 if (ext4_has_metadata_csum(inode->i_sb)) 1999 csum_size = sizeof(struct ext4_dir_entry_tail); 2000 2001 if (!de) { 2002 err = ext4_find_dest_de(dir, inode, bh, bh->b_data, 2003 blocksize - csum_size, fname, &de); 2004 if (err) 2005 return err; 2006 } 2007 BUFFER_TRACE(bh, "get_write_access"); 2008 err = ext4_journal_get_write_access(handle, bh); 2009 if (err) { 2010 ext4_std_error(dir->i_sb, err); 2011 return err; 2012 } 2013 2014 /* By now the buffer is marked for journaling */ 2015 ext4_insert_dentry(inode, de, blocksize, fname); 2016 2017 /* 2018 * XXX shouldn't update any times until successful 2019 * completion of syscall, but too many callers depend 2020 * on this. 2021 * 2022 * XXX similarly, too many callers depend on 2023 * ext4_new_inode() setting the times, but error 2024 * recovery deletes the inode, so the worst that can 2025 * happen is that the times are slightly out of date 2026 * and/or different from the directory change time. 2027 */ 2028 dir->i_mtime = dir->i_ctime = current_time(dir); 2029 ext4_update_dx_flag(dir); 2030 inode_inc_iversion(dir); 2031 ext4_mark_inode_dirty(handle, dir); 2032 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 2033 err = ext4_handle_dirty_dirblock(handle, dir, bh); 2034 if (err) 2035 ext4_std_error(dir->i_sb, err); 2036 return 0; 2037 } 2038 2039 /* 2040 * This converts a one block unindexed directory to a 3 block indexed 2041 * directory, and adds the dentry to the indexed directory. 2042 */ 2043 static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname, 2044 struct inode *dir, 2045 struct inode *inode, struct buffer_head *bh) 2046 { 2047 struct buffer_head *bh2; 2048 struct dx_root *root; 2049 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 2050 struct dx_entry *entries; 2051 struct ext4_dir_entry_2 *de, *de2; 2052 char *data2, *top; 2053 unsigned len; 2054 int retval; 2055 unsigned blocksize; 2056 ext4_lblk_t block; 2057 struct fake_dirent *fde; 2058 int csum_size = 0; 2059 2060 if (ext4_has_metadata_csum(inode->i_sb)) 2061 csum_size = sizeof(struct ext4_dir_entry_tail); 2062 2063 blocksize = dir->i_sb->s_blocksize; 2064 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); 2065 BUFFER_TRACE(bh, "get_write_access"); 2066 retval = ext4_journal_get_write_access(handle, bh); 2067 if (retval) { 2068 ext4_std_error(dir->i_sb, retval); 2069 brelse(bh); 2070 return retval; 2071 } 2072 root = (struct dx_root *) bh->b_data; 2073 2074 /* The 0th block becomes the root, move the dirents out */ 2075 fde = &root->dotdot; 2076 de = (struct ext4_dir_entry_2 *)((char *)fde + 2077 ext4_rec_len_from_disk(fde->rec_len, blocksize)); 2078 if ((char *) de >= (((char *) root) + blocksize)) { 2079 EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); 2080 brelse(bh); 2081 return -EFSCORRUPTED; 2082 } 2083 len = ((char *) root) + (blocksize - csum_size) - (char *) de; 2084 2085 /* Allocate new block for the 0th block's dirents */ 2086 bh2 = ext4_append(handle, dir, &block); 2087 if (IS_ERR(bh2)) { 2088 brelse(bh); 2089 return PTR_ERR(bh2); 2090 } 2091 ext4_set_inode_flag(dir, EXT4_INODE_INDEX); 2092 data2 = bh2->b_data; 2093 2094 memcpy(data2, de, len); 2095 de = (struct ext4_dir_entry_2 *) data2; 2096 top = data2 + len; 2097 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) 2098 de = de2; 2099 de->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) - 2100 (char *) de, blocksize); 2101 2102 if (csum_size) 2103 ext4_initialize_dirent_tail(bh2, blocksize); 2104 2105 /* Initialize the root; the dot dirents already exist */ 2106 de = (struct ext4_dir_entry_2 *) (&root->dotdot); 2107 de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), 2108 blocksize); 2109 memset (&root->info, 0, sizeof(root->info)); 2110 root->info.info_length = sizeof(root->info); 2111 root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; 2112 entries = root->entries; 2113 dx_set_block(entries, 1); 2114 dx_set_count(entries, 1); 2115 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); 2116 2117 /* Initialize as for dx_probe */ 2118 fname->hinfo.hash_version = root->info.hash_version; 2119 if (fname->hinfo.hash_version <= DX_HASH_TEA) 2120 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; 2121 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; 2122 ext4fs_dirhash(dir, fname_name(fname), fname_len(fname), &fname->hinfo); 2123 2124 memset(frames, 0, sizeof(frames)); 2125 frame = frames; 2126 frame->entries = entries; 2127 frame->at = entries; 2128 frame->bh = bh; 2129 2130 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2131 if (retval) 2132 goto out_frames; 2133 retval = ext4_handle_dirty_dirblock(handle, dir, bh2); 2134 if (retval) 2135 goto out_frames; 2136 2137 de = do_split(handle,dir, &bh2, frame, &fname->hinfo); 2138 if (IS_ERR(de)) { 2139 retval = PTR_ERR(de); 2140 goto out_frames; 2141 } 2142 2143 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2); 2144 out_frames: 2145 /* 2146 * Even if the block split failed, we have to properly write 2147 * out all the changes we did so far. Otherwise we can end up 2148 * with corrupted filesystem. 2149 */ 2150 if (retval) 2151 ext4_mark_inode_dirty(handle, dir); 2152 dx_release(frames); 2153 brelse(bh2); 2154 return retval; 2155 } 2156 2157 /* 2158 * ext4_add_entry() 2159 * 2160 * adds a file entry to the specified directory, using the same 2161 * semantics as ext4_find_entry(). It returns NULL if it failed. 2162 * 2163 * NOTE!! The inode part of 'de' is left at 0 - which means you 2164 * may not sleep between calling this and putting something into 2165 * the entry, as someone else might have used it while you slept. 2166 */ 2167 static int ext4_add_entry(handle_t *handle, struct dentry *dentry, 2168 struct inode *inode) 2169 { 2170 struct inode *dir = d_inode(dentry->d_parent); 2171 struct buffer_head *bh = NULL; 2172 struct ext4_dir_entry_2 *de; 2173 struct super_block *sb; 2174 #ifdef CONFIG_UNICODE 2175 struct ext4_sb_info *sbi; 2176 #endif 2177 struct ext4_filename fname; 2178 int retval; 2179 int dx_fallback=0; 2180 unsigned blocksize; 2181 ext4_lblk_t block, blocks; 2182 int csum_size = 0; 2183 2184 if (ext4_has_metadata_csum(inode->i_sb)) 2185 csum_size = sizeof(struct ext4_dir_entry_tail); 2186 2187 sb = dir->i_sb; 2188 blocksize = sb->s_blocksize; 2189 if (!dentry->d_name.len) 2190 return -EINVAL; 2191 2192 #ifdef CONFIG_UNICODE 2193 sbi = EXT4_SB(sb); 2194 if (ext4_has_strict_mode(sbi) && IS_CASEFOLDED(dir) && 2195 sbi->s_encoding && utf8_validate(sbi->s_encoding, &dentry->d_name)) 2196 return -EINVAL; 2197 #endif 2198 2199 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname); 2200 if (retval) 2201 return retval; 2202 2203 if (ext4_has_inline_data(dir)) { 2204 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode); 2205 if (retval < 0) 2206 goto out; 2207 if (retval == 1) { 2208 retval = 0; 2209 goto out; 2210 } 2211 } 2212 2213 if (is_dx(dir)) { 2214 retval = ext4_dx_add_entry(handle, &fname, dir, inode); 2215 if (!retval || (retval != ERR_BAD_DX_DIR)) 2216 goto out; 2217 /* Can we just ignore htree data? */ 2218 if (ext4_has_metadata_csum(sb)) { 2219 EXT4_ERROR_INODE(dir, 2220 "Directory has corrupted htree index."); 2221 retval = -EFSCORRUPTED; 2222 goto out; 2223 } 2224 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); 2225 dx_fallback++; 2226 ext4_mark_inode_dirty(handle, dir); 2227 } 2228 blocks = dir->i_size >> sb->s_blocksize_bits; 2229 for (block = 0; block < blocks; block++) { 2230 bh = ext4_read_dirblock(dir, block, DIRENT); 2231 if (bh == NULL) { 2232 bh = ext4_bread(handle, dir, block, 2233 EXT4_GET_BLOCKS_CREATE); 2234 goto add_to_new_block; 2235 } 2236 if (IS_ERR(bh)) { 2237 retval = PTR_ERR(bh); 2238 bh = NULL; 2239 goto out; 2240 } 2241 retval = add_dirent_to_buf(handle, &fname, dir, inode, 2242 NULL, bh); 2243 if (retval != -ENOSPC) 2244 goto out; 2245 2246 if (blocks == 1 && !dx_fallback && 2247 ext4_has_feature_dir_index(sb)) { 2248 retval = make_indexed_dir(handle, &fname, dir, 2249 inode, bh); 2250 bh = NULL; /* make_indexed_dir releases bh */ 2251 goto out; 2252 } 2253 brelse(bh); 2254 } 2255 bh = ext4_append(handle, dir, &block); 2256 add_to_new_block: 2257 if (IS_ERR(bh)) { 2258 retval = PTR_ERR(bh); 2259 bh = NULL; 2260 goto out; 2261 } 2262 de = (struct ext4_dir_entry_2 *) bh->b_data; 2263 de->inode = 0; 2264 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize); 2265 2266 if (csum_size) 2267 ext4_initialize_dirent_tail(bh, blocksize); 2268 2269 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh); 2270 out: 2271 ext4_fname_free_filename(&fname); 2272 brelse(bh); 2273 if (retval == 0) 2274 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); 2275 return retval; 2276 } 2277 2278 /* 2279 * Returns 0 for success, or a negative error value 2280 */ 2281 static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname, 2282 struct inode *dir, struct inode *inode) 2283 { 2284 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame; 2285 struct dx_entry *entries, *at; 2286 struct buffer_head *bh; 2287 struct super_block *sb = dir->i_sb; 2288 struct ext4_dir_entry_2 *de; 2289 int restart; 2290 int err; 2291 2292 again: 2293 restart = 0; 2294 frame = dx_probe(fname, dir, NULL, frames); 2295 if (IS_ERR(frame)) 2296 return PTR_ERR(frame); 2297 entries = frame->entries; 2298 at = frame->at; 2299 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT_HTREE); 2300 if (IS_ERR(bh)) { 2301 err = PTR_ERR(bh); 2302 bh = NULL; 2303 goto cleanup; 2304 } 2305 2306 BUFFER_TRACE(bh, "get_write_access"); 2307 err = ext4_journal_get_write_access(handle, bh); 2308 if (err) 2309 goto journal_error; 2310 2311 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh); 2312 if (err != -ENOSPC) 2313 goto cleanup; 2314 2315 err = 0; 2316 /* Block full, should compress but for now just split */ 2317 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n", 2318 dx_get_count(entries), dx_get_limit(entries))); 2319 /* Need to split index? */ 2320 if (dx_get_count(entries) == dx_get_limit(entries)) { 2321 ext4_lblk_t newblock; 2322 int levels = frame - frames + 1; 2323 unsigned int icount; 2324 int add_level = 1; 2325 struct dx_entry *entries2; 2326 struct dx_node *node2; 2327 struct buffer_head *bh2; 2328 2329 while (frame > frames) { 2330 if (dx_get_count((frame - 1)->entries) < 2331 dx_get_limit((frame - 1)->entries)) { 2332 add_level = 0; 2333 break; 2334 } 2335 frame--; /* split higher index block */ 2336 at = frame->at; 2337 entries = frame->entries; 2338 restart = 1; 2339 } 2340 if (add_level && levels == ext4_dir_htree_level(sb)) { 2341 ext4_warning(sb, "Directory (ino: %lu) index full, " 2342 "reach max htree level :%d", 2343 dir->i_ino, levels); 2344 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) { 2345 ext4_warning(sb, "Large directory feature is " 2346 "not enabled on this " 2347 "filesystem"); 2348 } 2349 err = -ENOSPC; 2350 goto cleanup; 2351 } 2352 icount = dx_get_count(entries); 2353 bh2 = ext4_append(handle, dir, &newblock); 2354 if (IS_ERR(bh2)) { 2355 err = PTR_ERR(bh2); 2356 goto cleanup; 2357 } 2358 node2 = (struct dx_node *)(bh2->b_data); 2359 entries2 = node2->entries; 2360 memset(&node2->fake, 0, sizeof(struct fake_dirent)); 2361 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, 2362 sb->s_blocksize); 2363 BUFFER_TRACE(frame->bh, "get_write_access"); 2364 err = ext4_journal_get_write_access(handle, frame->bh); 2365 if (err) 2366 goto journal_error; 2367 if (!add_level) { 2368 unsigned icount1 = icount/2, icount2 = icount - icount1; 2369 unsigned hash2 = dx_get_hash(entries + icount1); 2370 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n", 2371 icount1, icount2)); 2372 2373 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 2374 err = ext4_journal_get_write_access(handle, 2375 (frame - 1)->bh); 2376 if (err) 2377 goto journal_error; 2378 2379 memcpy((char *) entries2, (char *) (entries + icount1), 2380 icount2 * sizeof(struct dx_entry)); 2381 dx_set_count(entries, icount1); 2382 dx_set_count(entries2, icount2); 2383 dx_set_limit(entries2, dx_node_limit(dir)); 2384 2385 /* Which index block gets the new entry? */ 2386 if (at - entries >= icount1) { 2387 frame->at = at = at - entries - icount1 + entries2; 2388 frame->entries = entries = entries2; 2389 swap(frame->bh, bh2); 2390 } 2391 dx_insert_block((frame - 1), hash2, newblock); 2392 dxtrace(dx_show_index("node", frame->entries)); 2393 dxtrace(dx_show_index("node", 2394 ((struct dx_node *) bh2->b_data)->entries)); 2395 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2396 if (err) 2397 goto journal_error; 2398 brelse (bh2); 2399 err = ext4_handle_dirty_dx_node(handle, dir, 2400 (frame - 1)->bh); 2401 if (err) 2402 goto journal_error; 2403 if (restart) { 2404 err = ext4_handle_dirty_dx_node(handle, dir, 2405 frame->bh); 2406 goto journal_error; 2407 } 2408 } else { 2409 struct dx_root *dxroot; 2410 memcpy((char *) entries2, (char *) entries, 2411 icount * sizeof(struct dx_entry)); 2412 dx_set_limit(entries2, dx_node_limit(dir)); 2413 2414 /* Set up root */ 2415 dx_set_count(entries, 1); 2416 dx_set_block(entries + 0, newblock); 2417 dxroot = (struct dx_root *)frames[0].bh->b_data; 2418 dxroot->info.indirect_levels += 1; 2419 dxtrace(printk(KERN_DEBUG 2420 "Creating %d level index...\n", 2421 dxroot->info.indirect_levels)); 2422 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh); 2423 if (err) 2424 goto journal_error; 2425 err = ext4_handle_dirty_dx_node(handle, dir, bh2); 2426 brelse(bh2); 2427 restart = 1; 2428 goto journal_error; 2429 } 2430 } 2431 de = do_split(handle, dir, &bh, frame, &fname->hinfo); 2432 if (IS_ERR(de)) { 2433 err = PTR_ERR(de); 2434 goto cleanup; 2435 } 2436 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh); 2437 goto cleanup; 2438 2439 journal_error: 2440 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */ 2441 cleanup: 2442 brelse(bh); 2443 dx_release(frames); 2444 /* @restart is true means htree-path has been changed, we need to 2445 * repeat dx_probe() to find out valid htree-path 2446 */ 2447 if (restart && err == 0) 2448 goto again; 2449 return err; 2450 } 2451 2452 /* 2453 * ext4_generic_delete_entry deletes a directory entry by merging it 2454 * with the previous entry 2455 */ 2456 int ext4_generic_delete_entry(handle_t *handle, 2457 struct inode *dir, 2458 struct ext4_dir_entry_2 *de_del, 2459 struct buffer_head *bh, 2460 void *entry_buf, 2461 int buf_size, 2462 int csum_size) 2463 { 2464 struct ext4_dir_entry_2 *de, *pde; 2465 unsigned int blocksize = dir->i_sb->s_blocksize; 2466 int i; 2467 2468 i = 0; 2469 pde = NULL; 2470 de = (struct ext4_dir_entry_2 *)entry_buf; 2471 while (i < buf_size - csum_size) { 2472 if (ext4_check_dir_entry(dir, NULL, de, bh, 2473 bh->b_data, bh->b_size, i)) 2474 return -EFSCORRUPTED; 2475 if (de == de_del) { 2476 if (pde) 2477 pde->rec_len = ext4_rec_len_to_disk( 2478 ext4_rec_len_from_disk(pde->rec_len, 2479 blocksize) + 2480 ext4_rec_len_from_disk(de->rec_len, 2481 blocksize), 2482 blocksize); 2483 else 2484 de->inode = 0; 2485 inode_inc_iversion(dir); 2486 return 0; 2487 } 2488 i += ext4_rec_len_from_disk(de->rec_len, blocksize); 2489 pde = de; 2490 de = ext4_next_entry(de, blocksize); 2491 } 2492 return -ENOENT; 2493 } 2494 2495 static int ext4_delete_entry(handle_t *handle, 2496 struct inode *dir, 2497 struct ext4_dir_entry_2 *de_del, 2498 struct buffer_head *bh) 2499 { 2500 int err, csum_size = 0; 2501 2502 if (ext4_has_inline_data(dir)) { 2503 int has_inline_data = 1; 2504 err = ext4_delete_inline_entry(handle, dir, de_del, bh, 2505 &has_inline_data); 2506 if (has_inline_data) 2507 return err; 2508 } 2509 2510 if (ext4_has_metadata_csum(dir->i_sb)) 2511 csum_size = sizeof(struct ext4_dir_entry_tail); 2512 2513 BUFFER_TRACE(bh, "get_write_access"); 2514 err = ext4_journal_get_write_access(handle, bh); 2515 if (unlikely(err)) 2516 goto out; 2517 2518 err = ext4_generic_delete_entry(handle, dir, de_del, 2519 bh, bh->b_data, 2520 dir->i_sb->s_blocksize, csum_size); 2521 if (err) 2522 goto out; 2523 2524 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); 2525 err = ext4_handle_dirty_dirblock(handle, dir, bh); 2526 if (unlikely(err)) 2527 goto out; 2528 2529 return 0; 2530 out: 2531 if (err != -ENOENT) 2532 ext4_std_error(dir->i_sb, err); 2533 return err; 2534 } 2535 2536 /* 2537 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2 2538 * since this indicates that nlinks count was previously 1 to avoid overflowing 2539 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean 2540 * that subdirectory link counts are not being maintained accurately. 2541 * 2542 * The caller has already checked for i_nlink overflow in case the DIR_LINK 2543 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy 2544 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set 2545 * on regular files) and to avoid creating huge/slow non-HTREE directories. 2546 */ 2547 static void ext4_inc_count(handle_t *handle, struct inode *inode) 2548 { 2549 inc_nlink(inode); 2550 if (is_dx(inode) && 2551 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2)) 2552 set_nlink(inode, 1); 2553 } 2554 2555 /* 2556 * If a directory had nlink == 1, then we should let it be 1. This indicates 2557 * directory has >EXT4_LINK_MAX subdirs. 2558 */ 2559 static void ext4_dec_count(handle_t *handle, struct inode *inode) 2560 { 2561 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) 2562 drop_nlink(inode); 2563 } 2564 2565 2566 /* 2567 * Add non-directory inode to a directory. On success, the inode reference is 2568 * consumed by dentry is instantiation. This is also indicated by clearing of 2569 * *inodep pointer. On failure, the caller is responsible for dropping the 2570 * inode reference in the safe context. 2571 */ 2572 static int ext4_add_nondir(handle_t *handle, 2573 struct dentry *dentry, struct inode **inodep) 2574 { 2575 struct inode *dir = d_inode(dentry->d_parent); 2576 struct inode *inode = *inodep; 2577 int err = ext4_add_entry(handle, dentry, inode); 2578 if (!err) { 2579 ext4_mark_inode_dirty(handle, inode); 2580 if (IS_DIRSYNC(dir)) 2581 ext4_handle_sync(handle); 2582 d_instantiate_new(dentry, inode); 2583 *inodep = NULL; 2584 return 0; 2585 } 2586 drop_nlink(inode); 2587 ext4_orphan_add(handle, inode); 2588 unlock_new_inode(inode); 2589 return err; 2590 } 2591 2592 /* 2593 * By the time this is called, we already have created 2594 * the directory cache entry for the new file, but it 2595 * is so far negative - it has no inode. 2596 * 2597 * If the create succeeds, we fill in the inode information 2598 * with d_instantiate(). 2599 */ 2600 static int ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, 2601 bool excl) 2602 { 2603 handle_t *handle; 2604 struct inode *inode; 2605 int err, credits, retries = 0; 2606 2607 err = dquot_initialize(dir); 2608 if (err) 2609 return err; 2610 2611 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2612 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2613 retry: 2614 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2615 NULL, EXT4_HT_DIR, credits); 2616 handle = ext4_journal_current_handle(); 2617 err = PTR_ERR(inode); 2618 if (!IS_ERR(inode)) { 2619 inode->i_op = &ext4_file_inode_operations; 2620 inode->i_fop = &ext4_file_operations; 2621 ext4_set_aops(inode); 2622 err = ext4_add_nondir(handle, dentry, &inode); 2623 } 2624 if (handle) 2625 ext4_journal_stop(handle); 2626 if (!IS_ERR_OR_NULL(inode)) 2627 iput(inode); 2628 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2629 goto retry; 2630 return err; 2631 } 2632 2633 static int ext4_mknod(struct inode *dir, struct dentry *dentry, 2634 umode_t mode, dev_t rdev) 2635 { 2636 handle_t *handle; 2637 struct inode *inode; 2638 int err, credits, retries = 0; 2639 2640 err = dquot_initialize(dir); 2641 if (err) 2642 return err; 2643 2644 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2645 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2646 retry: 2647 inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0, 2648 NULL, EXT4_HT_DIR, credits); 2649 handle = ext4_journal_current_handle(); 2650 err = PTR_ERR(inode); 2651 if (!IS_ERR(inode)) { 2652 init_special_inode(inode, inode->i_mode, rdev); 2653 inode->i_op = &ext4_special_inode_operations; 2654 err = ext4_add_nondir(handle, dentry, &inode); 2655 } 2656 if (handle) 2657 ext4_journal_stop(handle); 2658 if (!IS_ERR_OR_NULL(inode)) 2659 iput(inode); 2660 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2661 goto retry; 2662 return err; 2663 } 2664 2665 static int ext4_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) 2666 { 2667 handle_t *handle; 2668 struct inode *inode; 2669 int err, retries = 0; 2670 2671 err = dquot_initialize(dir); 2672 if (err) 2673 return err; 2674 2675 retry: 2676 inode = ext4_new_inode_start_handle(dir, mode, 2677 NULL, 0, NULL, 2678 EXT4_HT_DIR, 2679 EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 2680 4 + EXT4_XATTR_TRANS_BLOCKS); 2681 handle = ext4_journal_current_handle(); 2682 err = PTR_ERR(inode); 2683 if (!IS_ERR(inode)) { 2684 inode->i_op = &ext4_file_inode_operations; 2685 inode->i_fop = &ext4_file_operations; 2686 ext4_set_aops(inode); 2687 d_tmpfile(dentry, inode); 2688 err = ext4_orphan_add(handle, inode); 2689 if (err) 2690 goto err_unlock_inode; 2691 mark_inode_dirty(inode); 2692 unlock_new_inode(inode); 2693 } 2694 if (handle) 2695 ext4_journal_stop(handle); 2696 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2697 goto retry; 2698 return err; 2699 err_unlock_inode: 2700 ext4_journal_stop(handle); 2701 unlock_new_inode(inode); 2702 return err; 2703 } 2704 2705 struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode, 2706 struct ext4_dir_entry_2 *de, 2707 int blocksize, int csum_size, 2708 unsigned int parent_ino, int dotdot_real_len) 2709 { 2710 de->inode = cpu_to_le32(inode->i_ino); 2711 de->name_len = 1; 2712 de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), 2713 blocksize); 2714 strcpy(de->name, "."); 2715 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2716 2717 de = ext4_next_entry(de, blocksize); 2718 de->inode = cpu_to_le32(parent_ino); 2719 de->name_len = 2; 2720 if (!dotdot_real_len) 2721 de->rec_len = ext4_rec_len_to_disk(blocksize - 2722 (csum_size + EXT4_DIR_REC_LEN(1)), 2723 blocksize); 2724 else 2725 de->rec_len = ext4_rec_len_to_disk( 2726 EXT4_DIR_REC_LEN(de->name_len), blocksize); 2727 strcpy(de->name, ".."); 2728 ext4_set_de_type(inode->i_sb, de, S_IFDIR); 2729 2730 return ext4_next_entry(de, blocksize); 2731 } 2732 2733 static int ext4_init_new_dir(handle_t *handle, struct inode *dir, 2734 struct inode *inode) 2735 { 2736 struct buffer_head *dir_block = NULL; 2737 struct ext4_dir_entry_2 *de; 2738 ext4_lblk_t block = 0; 2739 unsigned int blocksize = dir->i_sb->s_blocksize; 2740 int csum_size = 0; 2741 int err; 2742 2743 if (ext4_has_metadata_csum(dir->i_sb)) 2744 csum_size = sizeof(struct ext4_dir_entry_tail); 2745 2746 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { 2747 err = ext4_try_create_inline_dir(handle, dir, inode); 2748 if (err < 0 && err != -ENOSPC) 2749 goto out; 2750 if (!err) 2751 goto out; 2752 } 2753 2754 inode->i_size = 0; 2755 dir_block = ext4_append(handle, inode, &block); 2756 if (IS_ERR(dir_block)) 2757 return PTR_ERR(dir_block); 2758 de = (struct ext4_dir_entry_2 *)dir_block->b_data; 2759 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0); 2760 set_nlink(inode, 2); 2761 if (csum_size) 2762 ext4_initialize_dirent_tail(dir_block, blocksize); 2763 2764 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); 2765 err = ext4_handle_dirty_dirblock(handle, inode, dir_block); 2766 if (err) 2767 goto out; 2768 set_buffer_verified(dir_block); 2769 out: 2770 brelse(dir_block); 2771 return err; 2772 } 2773 2774 static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) 2775 { 2776 handle_t *handle; 2777 struct inode *inode; 2778 int err, credits, retries = 0; 2779 2780 if (EXT4_DIR_LINK_MAX(dir)) 2781 return -EMLINK; 2782 2783 err = dquot_initialize(dir); 2784 if (err) 2785 return err; 2786 2787 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 2788 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3); 2789 retry: 2790 inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode, 2791 &dentry->d_name, 2792 0, NULL, EXT4_HT_DIR, credits); 2793 handle = ext4_journal_current_handle(); 2794 err = PTR_ERR(inode); 2795 if (IS_ERR(inode)) 2796 goto out_stop; 2797 2798 inode->i_op = &ext4_dir_inode_operations; 2799 inode->i_fop = &ext4_dir_operations; 2800 err = ext4_init_new_dir(handle, dir, inode); 2801 if (err) 2802 goto out_clear_inode; 2803 err = ext4_mark_inode_dirty(handle, inode); 2804 if (!err) 2805 err = ext4_add_entry(handle, dentry, inode); 2806 if (err) { 2807 out_clear_inode: 2808 clear_nlink(inode); 2809 ext4_orphan_add(handle, inode); 2810 unlock_new_inode(inode); 2811 ext4_mark_inode_dirty(handle, inode); 2812 ext4_journal_stop(handle); 2813 iput(inode); 2814 goto out_retry; 2815 } 2816 ext4_inc_count(handle, dir); 2817 ext4_update_dx_flag(dir); 2818 err = ext4_mark_inode_dirty(handle, dir); 2819 if (err) 2820 goto out_clear_inode; 2821 d_instantiate_new(dentry, inode); 2822 if (IS_DIRSYNC(dir)) 2823 ext4_handle_sync(handle); 2824 2825 out_stop: 2826 if (handle) 2827 ext4_journal_stop(handle); 2828 out_retry: 2829 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 2830 goto retry; 2831 return err; 2832 } 2833 2834 /* 2835 * routine to check that the specified directory is empty (for rmdir) 2836 */ 2837 bool ext4_empty_dir(struct inode *inode) 2838 { 2839 unsigned int offset; 2840 struct buffer_head *bh; 2841 struct ext4_dir_entry_2 *de; 2842 struct super_block *sb; 2843 2844 if (ext4_has_inline_data(inode)) { 2845 int has_inline_data = 1; 2846 int ret; 2847 2848 ret = empty_inline_dir(inode, &has_inline_data); 2849 if (has_inline_data) 2850 return ret; 2851 } 2852 2853 sb = inode->i_sb; 2854 if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) { 2855 EXT4_ERROR_INODE(inode, "invalid size"); 2856 return true; 2857 } 2858 /* The first directory block must not be a hole, 2859 * so treat it as DIRENT_HTREE 2860 */ 2861 bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE); 2862 if (IS_ERR(bh)) 2863 return true; 2864 2865 de = (struct ext4_dir_entry_2 *) bh->b_data; 2866 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size, 2867 0) || 2868 le32_to_cpu(de->inode) != inode->i_ino || strcmp(".", de->name)) { 2869 ext4_warning_inode(inode, "directory missing '.'"); 2870 brelse(bh); 2871 return true; 2872 } 2873 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2874 de = ext4_next_entry(de, sb->s_blocksize); 2875 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size, 2876 offset) || 2877 le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) { 2878 ext4_warning_inode(inode, "directory missing '..'"); 2879 brelse(bh); 2880 return true; 2881 } 2882 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2883 while (offset < inode->i_size) { 2884 if (!(offset & (sb->s_blocksize - 1))) { 2885 unsigned int lblock; 2886 brelse(bh); 2887 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); 2888 bh = ext4_read_dirblock(inode, lblock, EITHER); 2889 if (bh == NULL) { 2890 offset += sb->s_blocksize; 2891 continue; 2892 } 2893 if (IS_ERR(bh)) 2894 return true; 2895 } 2896 de = (struct ext4_dir_entry_2 *) (bh->b_data + 2897 (offset & (sb->s_blocksize - 1))); 2898 if (ext4_check_dir_entry(inode, NULL, de, bh, 2899 bh->b_data, bh->b_size, offset)) { 2900 offset = (offset | (sb->s_blocksize - 1)) + 1; 2901 continue; 2902 } 2903 if (le32_to_cpu(de->inode)) { 2904 brelse(bh); 2905 return false; 2906 } 2907 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); 2908 } 2909 brelse(bh); 2910 return true; 2911 } 2912 2913 /* 2914 * ext4_orphan_add() links an unlinked or truncated inode into a list of 2915 * such inodes, starting at the superblock, in case we crash before the 2916 * file is closed/deleted, or in case the inode truncate spans multiple 2917 * transactions and the last transaction is not recovered after a crash. 2918 * 2919 * At filesystem recovery time, we walk this list deleting unlinked 2920 * inodes and truncating linked inodes in ext4_orphan_cleanup(). 2921 * 2922 * Orphan list manipulation functions must be called under i_mutex unless 2923 * we are just creating the inode or deleting it. 2924 */ 2925 int ext4_orphan_add(handle_t *handle, struct inode *inode) 2926 { 2927 struct super_block *sb = inode->i_sb; 2928 struct ext4_sb_info *sbi = EXT4_SB(sb); 2929 struct ext4_iloc iloc; 2930 int err = 0, rc; 2931 bool dirty = false; 2932 2933 if (!sbi->s_journal || is_bad_inode(inode)) 2934 return 0; 2935 2936 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 2937 !inode_is_locked(inode)); 2938 /* 2939 * Exit early if inode already is on orphan list. This is a big speedup 2940 * since we don't have to contend on the global s_orphan_lock. 2941 */ 2942 if (!list_empty(&EXT4_I(inode)->i_orphan)) 2943 return 0; 2944 2945 /* 2946 * Orphan handling is only valid for files with data blocks 2947 * being truncated, or files being unlinked. Note that we either 2948 * hold i_mutex, or the inode can not be referenced from outside, 2949 * so i_nlink should not be bumped due to race 2950 */ 2951 J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 2952 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 2953 2954 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2955 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 2956 if (err) 2957 goto out; 2958 2959 err = ext4_reserve_inode_write(handle, inode, &iloc); 2960 if (err) 2961 goto out; 2962 2963 mutex_lock(&sbi->s_orphan_lock); 2964 /* 2965 * Due to previous errors inode may be already a part of on-disk 2966 * orphan list. If so skip on-disk list modification. 2967 */ 2968 if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) > 2969 (le32_to_cpu(sbi->s_es->s_inodes_count))) { 2970 /* Insert this inode at the head of the on-disk orphan list */ 2971 NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan); 2972 sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 2973 dirty = true; 2974 } 2975 list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan); 2976 mutex_unlock(&sbi->s_orphan_lock); 2977 2978 if (dirty) { 2979 err = ext4_handle_dirty_super(handle, sb); 2980 rc = ext4_mark_iloc_dirty(handle, inode, &iloc); 2981 if (!err) 2982 err = rc; 2983 if (err) { 2984 /* 2985 * We have to remove inode from in-memory list if 2986 * addition to on disk orphan list failed. Stray orphan 2987 * list entries can cause panics at unmount time. 2988 */ 2989 mutex_lock(&sbi->s_orphan_lock); 2990 list_del_init(&EXT4_I(inode)->i_orphan); 2991 mutex_unlock(&sbi->s_orphan_lock); 2992 } 2993 } else 2994 brelse(iloc.bh); 2995 2996 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 2997 jbd_debug(4, "orphan inode %lu will point to %d\n", 2998 inode->i_ino, NEXT_ORPHAN(inode)); 2999 out: 3000 ext4_std_error(sb, err); 3001 return err; 3002 } 3003 3004 /* 3005 * ext4_orphan_del() removes an unlinked or truncated inode from the list 3006 * of such inodes stored on disk, because it is finally being cleaned up. 3007 */ 3008 int ext4_orphan_del(handle_t *handle, struct inode *inode) 3009 { 3010 struct list_head *prev; 3011 struct ext4_inode_info *ei = EXT4_I(inode); 3012 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 3013 __u32 ino_next; 3014 struct ext4_iloc iloc; 3015 int err = 0; 3016 3017 if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS)) 3018 return 0; 3019 3020 WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) && 3021 !inode_is_locked(inode)); 3022 /* Do this quick check before taking global s_orphan_lock. */ 3023 if (list_empty(&ei->i_orphan)) 3024 return 0; 3025 3026 if (handle) { 3027 /* Grab inode buffer early before taking global s_orphan_lock */ 3028 err = ext4_reserve_inode_write(handle, inode, &iloc); 3029 } 3030 3031 mutex_lock(&sbi->s_orphan_lock); 3032 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 3033 3034 prev = ei->i_orphan.prev; 3035 list_del_init(&ei->i_orphan); 3036 3037 /* If we're on an error path, we may not have a valid 3038 * transaction handle with which to update the orphan list on 3039 * disk, but we still need to remove the inode from the linked 3040 * list in memory. */ 3041 if (!handle || err) { 3042 mutex_unlock(&sbi->s_orphan_lock); 3043 goto out_err; 3044 } 3045 3046 ino_next = NEXT_ORPHAN(inode); 3047 if (prev == &sbi->s_orphan) { 3048 jbd_debug(4, "superblock will point to %u\n", ino_next); 3049 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 3050 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 3051 if (err) { 3052 mutex_unlock(&sbi->s_orphan_lock); 3053 goto out_brelse; 3054 } 3055 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 3056 mutex_unlock(&sbi->s_orphan_lock); 3057 err = ext4_handle_dirty_super(handle, inode->i_sb); 3058 } else { 3059 struct ext4_iloc iloc2; 3060 struct inode *i_prev = 3061 &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; 3062 3063 jbd_debug(4, "orphan inode %lu will point to %u\n", 3064 i_prev->i_ino, ino_next); 3065 err = ext4_reserve_inode_write(handle, i_prev, &iloc2); 3066 if (err) { 3067 mutex_unlock(&sbi->s_orphan_lock); 3068 goto out_brelse; 3069 } 3070 NEXT_ORPHAN(i_prev) = ino_next; 3071 err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); 3072 mutex_unlock(&sbi->s_orphan_lock); 3073 } 3074 if (err) 3075 goto out_brelse; 3076 NEXT_ORPHAN(inode) = 0; 3077 err = ext4_mark_iloc_dirty(handle, inode, &iloc); 3078 out_err: 3079 ext4_std_error(inode->i_sb, err); 3080 return err; 3081 3082 out_brelse: 3083 brelse(iloc.bh); 3084 goto out_err; 3085 } 3086 3087 static int ext4_rmdir(struct inode *dir, struct dentry *dentry) 3088 { 3089 int retval; 3090 struct inode *inode; 3091 struct buffer_head *bh; 3092 struct ext4_dir_entry_2 *de; 3093 handle_t *handle = NULL; 3094 3095 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3096 return -EIO; 3097 3098 /* Initialize quotas before so that eventual writes go in 3099 * separate transaction */ 3100 retval = dquot_initialize(dir); 3101 if (retval) 3102 return retval; 3103 retval = dquot_initialize(d_inode(dentry)); 3104 if (retval) 3105 return retval; 3106 3107 retval = -ENOENT; 3108 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 3109 if (IS_ERR(bh)) 3110 return PTR_ERR(bh); 3111 if (!bh) 3112 goto end_rmdir; 3113 3114 inode = d_inode(dentry); 3115 3116 retval = -EFSCORRUPTED; 3117 if (le32_to_cpu(de->inode) != inode->i_ino) 3118 goto end_rmdir; 3119 3120 retval = -ENOTEMPTY; 3121 if (!ext4_empty_dir(inode)) 3122 goto end_rmdir; 3123 3124 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3125 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 3126 if (IS_ERR(handle)) { 3127 retval = PTR_ERR(handle); 3128 handle = NULL; 3129 goto end_rmdir; 3130 } 3131 3132 if (IS_DIRSYNC(dir)) 3133 ext4_handle_sync(handle); 3134 3135 retval = ext4_delete_entry(handle, dir, de, bh); 3136 if (retval) 3137 goto end_rmdir; 3138 if (!EXT4_DIR_LINK_EMPTY(inode)) 3139 ext4_warning_inode(inode, 3140 "empty directory '%.*s' has too many links (%u)", 3141 dentry->d_name.len, dentry->d_name.name, 3142 inode->i_nlink); 3143 inode_inc_iversion(inode); 3144 clear_nlink(inode); 3145 /* There's no need to set i_disksize: the fact that i_nlink is 3146 * zero will ensure that the right thing happens during any 3147 * recovery. */ 3148 inode->i_size = 0; 3149 ext4_orphan_add(handle, inode); 3150 inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); 3151 ext4_mark_inode_dirty(handle, inode); 3152 ext4_dec_count(handle, dir); 3153 ext4_update_dx_flag(dir); 3154 ext4_mark_inode_dirty(handle, dir); 3155 3156 #ifdef CONFIG_UNICODE 3157 /* VFS negative dentries are incompatible with Encoding and 3158 * Case-insensitiveness. Eventually we'll want avoid 3159 * invalidating the dentries here, alongside with returning the 3160 * negative dentries at ext4_lookup(), when it is better 3161 * supported by the VFS for the CI case. 3162 */ 3163 if (IS_CASEFOLDED(dir)) 3164 d_invalidate(dentry); 3165 #endif 3166 3167 end_rmdir: 3168 brelse(bh); 3169 if (handle) 3170 ext4_journal_stop(handle); 3171 return retval; 3172 } 3173 3174 static int ext4_unlink(struct inode *dir, struct dentry *dentry) 3175 { 3176 int retval; 3177 struct inode *inode; 3178 struct buffer_head *bh; 3179 struct ext4_dir_entry_2 *de; 3180 handle_t *handle = NULL; 3181 3182 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3183 return -EIO; 3184 3185 trace_ext4_unlink_enter(dir, dentry); 3186 /* Initialize quotas before so that eventual writes go 3187 * in separate transaction */ 3188 retval = dquot_initialize(dir); 3189 if (retval) 3190 return retval; 3191 retval = dquot_initialize(d_inode(dentry)); 3192 if (retval) 3193 return retval; 3194 3195 retval = -ENOENT; 3196 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL); 3197 if (IS_ERR(bh)) 3198 return PTR_ERR(bh); 3199 if (!bh) 3200 goto end_unlink; 3201 3202 inode = d_inode(dentry); 3203 3204 retval = -EFSCORRUPTED; 3205 if (le32_to_cpu(de->inode) != inode->i_ino) 3206 goto end_unlink; 3207 3208 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3209 EXT4_DATA_TRANS_BLOCKS(dir->i_sb)); 3210 if (IS_ERR(handle)) { 3211 retval = PTR_ERR(handle); 3212 handle = NULL; 3213 goto end_unlink; 3214 } 3215 3216 if (IS_DIRSYNC(dir)) 3217 ext4_handle_sync(handle); 3218 3219 retval = ext4_delete_entry(handle, dir, de, bh); 3220 if (retval) 3221 goto end_unlink; 3222 dir->i_ctime = dir->i_mtime = current_time(dir); 3223 ext4_update_dx_flag(dir); 3224 ext4_mark_inode_dirty(handle, dir); 3225 if (inode->i_nlink == 0) 3226 ext4_warning_inode(inode, "Deleting file '%.*s' with no links", 3227 dentry->d_name.len, dentry->d_name.name); 3228 else 3229 drop_nlink(inode); 3230 if (!inode->i_nlink) 3231 ext4_orphan_add(handle, inode); 3232 inode->i_ctime = current_time(inode); 3233 ext4_mark_inode_dirty(handle, inode); 3234 3235 #ifdef CONFIG_UNICODE 3236 /* VFS negative dentries are incompatible with Encoding and 3237 * Case-insensitiveness. Eventually we'll want avoid 3238 * invalidating the dentries here, alongside with returning the 3239 * negative dentries at ext4_lookup(), when it is better 3240 * supported by the VFS for the CI case. 3241 */ 3242 if (IS_CASEFOLDED(dir)) 3243 d_invalidate(dentry); 3244 #endif 3245 3246 end_unlink: 3247 brelse(bh); 3248 if (handle) 3249 ext4_journal_stop(handle); 3250 trace_ext4_unlink_exit(dentry, retval); 3251 return retval; 3252 } 3253 3254 static int ext4_symlink(struct inode *dir, 3255 struct dentry *dentry, const char *symname) 3256 { 3257 handle_t *handle; 3258 struct inode *inode; 3259 int err, len = strlen(symname); 3260 int credits; 3261 struct fscrypt_str disk_link; 3262 3263 if (unlikely(ext4_forced_shutdown(EXT4_SB(dir->i_sb)))) 3264 return -EIO; 3265 3266 err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize, 3267 &disk_link); 3268 if (err) 3269 return err; 3270 3271 err = dquot_initialize(dir); 3272 if (err) 3273 return err; 3274 3275 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3276 /* 3277 * For non-fast symlinks, we just allocate inode and put it on 3278 * orphan list in the first transaction => we need bitmap, 3279 * group descriptor, sb, inode block, quota blocks, and 3280 * possibly selinux xattr blocks. 3281 */ 3282 credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 3283 EXT4_XATTR_TRANS_BLOCKS; 3284 } else { 3285 /* 3286 * Fast symlink. We have to add entry to directory 3287 * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), 3288 * allocate new inode (bitmap, group descriptor, inode block, 3289 * quota blocks, sb is already counted in previous macros). 3290 */ 3291 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3292 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3; 3293 } 3294 3295 inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO, 3296 &dentry->d_name, 0, NULL, 3297 EXT4_HT_DIR, credits); 3298 handle = ext4_journal_current_handle(); 3299 if (IS_ERR(inode)) { 3300 if (handle) 3301 ext4_journal_stop(handle); 3302 return PTR_ERR(inode); 3303 } 3304 3305 if (IS_ENCRYPTED(inode)) { 3306 err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link); 3307 if (err) 3308 goto err_drop_inode; 3309 inode->i_op = &ext4_encrypted_symlink_inode_operations; 3310 } 3311 3312 if ((disk_link.len > EXT4_N_BLOCKS * 4)) { 3313 if (!IS_ENCRYPTED(inode)) 3314 inode->i_op = &ext4_symlink_inode_operations; 3315 inode_nohighmem(inode); 3316 ext4_set_aops(inode); 3317 /* 3318 * We cannot call page_symlink() with transaction started 3319 * because it calls into ext4_write_begin() which can wait 3320 * for transaction commit if we are running out of space 3321 * and thus we deadlock. So we have to stop transaction now 3322 * and restart it when symlink contents is written. 3323 * 3324 * To keep fs consistent in case of crash, we have to put inode 3325 * to orphan list in the mean time. 3326 */ 3327 drop_nlink(inode); 3328 err = ext4_orphan_add(handle, inode); 3329 ext4_journal_stop(handle); 3330 handle = NULL; 3331 if (err) 3332 goto err_drop_inode; 3333 err = __page_symlink(inode, disk_link.name, disk_link.len, 1); 3334 if (err) 3335 goto err_drop_inode; 3336 /* 3337 * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS 3338 * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified 3339 */ 3340 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3341 EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3342 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); 3343 if (IS_ERR(handle)) { 3344 err = PTR_ERR(handle); 3345 handle = NULL; 3346 goto err_drop_inode; 3347 } 3348 set_nlink(inode, 1); 3349 err = ext4_orphan_del(handle, inode); 3350 if (err) 3351 goto err_drop_inode; 3352 } else { 3353 /* clear the extent format for fast symlink */ 3354 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); 3355 if (!IS_ENCRYPTED(inode)) { 3356 inode->i_op = &ext4_fast_symlink_inode_operations; 3357 inode->i_link = (char *)&EXT4_I(inode)->i_data; 3358 } 3359 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name, 3360 disk_link.len); 3361 inode->i_size = disk_link.len - 1; 3362 } 3363 EXT4_I(inode)->i_disksize = inode->i_size; 3364 err = ext4_add_nondir(handle, dentry, &inode); 3365 if (handle) 3366 ext4_journal_stop(handle); 3367 if (inode) 3368 iput(inode); 3369 goto out_free_encrypted_link; 3370 3371 err_drop_inode: 3372 if (handle) 3373 ext4_journal_stop(handle); 3374 clear_nlink(inode); 3375 unlock_new_inode(inode); 3376 iput(inode); 3377 out_free_encrypted_link: 3378 if (disk_link.name != (unsigned char *)symname) 3379 kfree(disk_link.name); 3380 return err; 3381 } 3382 3383 static int ext4_link(struct dentry *old_dentry, 3384 struct inode *dir, struct dentry *dentry) 3385 { 3386 handle_t *handle; 3387 struct inode *inode = d_inode(old_dentry); 3388 int err, retries = 0; 3389 3390 if (inode->i_nlink >= EXT4_LINK_MAX) 3391 return -EMLINK; 3392 3393 err = fscrypt_prepare_link(old_dentry, dir, dentry); 3394 if (err) 3395 return err; 3396 3397 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) && 3398 (!projid_eq(EXT4_I(dir)->i_projid, 3399 EXT4_I(old_dentry->d_inode)->i_projid))) 3400 return -EXDEV; 3401 3402 err = dquot_initialize(dir); 3403 if (err) 3404 return err; 3405 3406 retry: 3407 handle = ext4_journal_start(dir, EXT4_HT_DIR, 3408 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + 3409 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1); 3410 if (IS_ERR(handle)) 3411 return PTR_ERR(handle); 3412 3413 if (IS_DIRSYNC(dir)) 3414 ext4_handle_sync(handle); 3415 3416 inode->i_ctime = current_time(inode); 3417 ext4_inc_count(handle, inode); 3418 ihold(inode); 3419 3420 err = ext4_add_entry(handle, dentry, inode); 3421 if (!err) { 3422 ext4_mark_inode_dirty(handle, inode); 3423 /* this can happen only for tmpfile being 3424 * linked the first time 3425 */ 3426 if (inode->i_nlink == 1) 3427 ext4_orphan_del(handle, inode); 3428 d_instantiate(dentry, inode); 3429 } else { 3430 drop_nlink(inode); 3431 iput(inode); 3432 } 3433 ext4_journal_stop(handle); 3434 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) 3435 goto retry; 3436 return err; 3437 } 3438 3439 3440 /* 3441 * Try to find buffer head where contains the parent block. 3442 * It should be the inode block if it is inlined or the 1st block 3443 * if it is a normal dir. 3444 */ 3445 static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, 3446 struct inode *inode, 3447 int *retval, 3448 struct ext4_dir_entry_2 **parent_de, 3449 int *inlined) 3450 { 3451 struct buffer_head *bh; 3452 3453 if (!ext4_has_inline_data(inode)) { 3454 /* The first directory block must not be a hole, so 3455 * treat it as DIRENT_HTREE 3456 */ 3457 bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE); 3458 if (IS_ERR(bh)) { 3459 *retval = PTR_ERR(bh); 3460 return NULL; 3461 } 3462 *parent_de = ext4_next_entry( 3463 (struct ext4_dir_entry_2 *)bh->b_data, 3464 inode->i_sb->s_blocksize); 3465 return bh; 3466 } 3467 3468 *inlined = 1; 3469 return ext4_get_first_inline_block(inode, parent_de, retval); 3470 } 3471 3472 struct ext4_renament { 3473 struct inode *dir; 3474 struct dentry *dentry; 3475 struct inode *inode; 3476 bool is_dir; 3477 int dir_nlink_delta; 3478 3479 /* entry for "dentry" */ 3480 struct buffer_head *bh; 3481 struct ext4_dir_entry_2 *de; 3482 int inlined; 3483 3484 /* entry for ".." in inode if it's a directory */ 3485 struct buffer_head *dir_bh; 3486 struct ext4_dir_entry_2 *parent_de; 3487 int dir_inlined; 3488 }; 3489 3490 static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) 3491 { 3492 int retval; 3493 3494 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, 3495 &retval, &ent->parent_de, 3496 &ent->dir_inlined); 3497 if (!ent->dir_bh) 3498 return retval; 3499 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino) 3500 return -EFSCORRUPTED; 3501 BUFFER_TRACE(ent->dir_bh, "get_write_access"); 3502 return ext4_journal_get_write_access(handle, ent->dir_bh); 3503 } 3504 3505 static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, 3506 unsigned dir_ino) 3507 { 3508 int retval; 3509 3510 ent->parent_de->inode = cpu_to_le32(dir_ino); 3511 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); 3512 if (!ent->dir_inlined) { 3513 if (is_dx(ent->inode)) { 3514 retval = ext4_handle_dirty_dx_node(handle, 3515 ent->inode, 3516 ent->dir_bh); 3517 } else { 3518 retval = ext4_handle_dirty_dirblock(handle, ent->inode, 3519 ent->dir_bh); 3520 } 3521 } else { 3522 retval = ext4_mark_inode_dirty(handle, ent->inode); 3523 } 3524 if (retval) { 3525 ext4_std_error(ent->dir->i_sb, retval); 3526 return retval; 3527 } 3528 return 0; 3529 } 3530 3531 static int ext4_setent(handle_t *handle, struct ext4_renament *ent, 3532 unsigned ino, unsigned file_type) 3533 { 3534 int retval; 3535 3536 BUFFER_TRACE(ent->bh, "get write access"); 3537 retval = ext4_journal_get_write_access(handle, ent->bh); 3538 if (retval) 3539 return retval; 3540 ent->de->inode = cpu_to_le32(ino); 3541 if (ext4_has_feature_filetype(ent->dir->i_sb)) 3542 ent->de->file_type = file_type; 3543 inode_inc_iversion(ent->dir); 3544 ent->dir->i_ctime = ent->dir->i_mtime = 3545 current_time(ent->dir); 3546 ext4_mark_inode_dirty(handle, ent->dir); 3547 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata"); 3548 if (!ent->inlined) { 3549 retval = ext4_handle_dirty_dirblock(handle, ent->dir, ent->bh); 3550 if (unlikely(retval)) { 3551 ext4_std_error(ent->dir->i_sb, retval); 3552 return retval; 3553 } 3554 } 3555 brelse(ent->bh); 3556 ent->bh = NULL; 3557 3558 return 0; 3559 } 3560 3561 static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, 3562 const struct qstr *d_name) 3563 { 3564 int retval = -ENOENT; 3565 struct buffer_head *bh; 3566 struct ext4_dir_entry_2 *de; 3567 3568 bh = ext4_find_entry(dir, d_name, &de, NULL); 3569 if (IS_ERR(bh)) 3570 return PTR_ERR(bh); 3571 if (bh) { 3572 retval = ext4_delete_entry(handle, dir, de, bh); 3573 brelse(bh); 3574 } 3575 return retval; 3576 } 3577 3578 static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent, 3579 int force_reread) 3580 { 3581 int retval; 3582 /* 3583 * ent->de could have moved from under us during htree split, so make 3584 * sure that we are deleting the right entry. We might also be pointing 3585 * to a stale entry in the unused part of ent->bh so just checking inum 3586 * and the name isn't enough. 3587 */ 3588 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino || 3589 ent->de->name_len != ent->dentry->d_name.len || 3590 strncmp(ent->de->name, ent->dentry->d_name.name, 3591 ent->de->name_len) || 3592 force_reread) { 3593 retval = ext4_find_delete_entry(handle, ent->dir, 3594 &ent->dentry->d_name); 3595 } else { 3596 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh); 3597 if (retval == -ENOENT) { 3598 retval = ext4_find_delete_entry(handle, ent->dir, 3599 &ent->dentry->d_name); 3600 } 3601 } 3602 3603 if (retval) { 3604 ext4_warning_inode(ent->dir, 3605 "Deleting old file: nlink %d, error=%d", 3606 ent->dir->i_nlink, retval); 3607 } 3608 } 3609 3610 static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent) 3611 { 3612 if (ent->dir_nlink_delta) { 3613 if (ent->dir_nlink_delta == -1) 3614 ext4_dec_count(handle, ent->dir); 3615 else 3616 ext4_inc_count(handle, ent->dir); 3617 ext4_mark_inode_dirty(handle, ent->dir); 3618 } 3619 } 3620 3621 static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent, 3622 int credits, handle_t **h) 3623 { 3624 struct inode *wh; 3625 handle_t *handle; 3626 int retries = 0; 3627 3628 /* 3629 * for inode block, sb block, group summaries, 3630 * and inode bitmap 3631 */ 3632 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) + 3633 EXT4_XATTR_TRANS_BLOCKS + 4); 3634 retry: 3635 wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE, 3636 &ent->dentry->d_name, 0, NULL, 3637 EXT4_HT_DIR, credits); 3638 3639 handle = ext4_journal_current_handle(); 3640 if (IS_ERR(wh)) { 3641 if (handle) 3642 ext4_journal_stop(handle); 3643 if (PTR_ERR(wh) == -ENOSPC && 3644 ext4_should_retry_alloc(ent->dir->i_sb, &retries)) 3645 goto retry; 3646 } else { 3647 *h = handle; 3648 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV); 3649 wh->i_op = &ext4_special_inode_operations; 3650 } 3651 return wh; 3652 } 3653 3654 /* 3655 * Anybody can rename anything with this: the permission checks are left to the 3656 * higher-level routines. 3657 * 3658 * n.b. old_{dentry,inode) refers to the source dentry/inode 3659 * while new_{dentry,inode) refers to the destination dentry/inode 3660 * This comes from rename(const char *oldpath, const char *newpath) 3661 */ 3662 static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, 3663 struct inode *new_dir, struct dentry *new_dentry, 3664 unsigned int flags) 3665 { 3666 handle_t *handle = NULL; 3667 struct ext4_renament old = { 3668 .dir = old_dir, 3669 .dentry = old_dentry, 3670 .inode = d_inode(old_dentry), 3671 }; 3672 struct ext4_renament new = { 3673 .dir = new_dir, 3674 .dentry = new_dentry, 3675 .inode = d_inode(new_dentry), 3676 }; 3677 int force_reread; 3678 int retval; 3679 struct inode *whiteout = NULL; 3680 int credits; 3681 u8 old_file_type; 3682 3683 if (new.inode && new.inode->i_nlink == 0) { 3684 EXT4_ERROR_INODE(new.inode, 3685 "target of rename is already freed"); 3686 return -EFSCORRUPTED; 3687 } 3688 3689 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) && 3690 (!projid_eq(EXT4_I(new_dir)->i_projid, 3691 EXT4_I(old_dentry->d_inode)->i_projid))) 3692 return -EXDEV; 3693 3694 retval = dquot_initialize(old.dir); 3695 if (retval) 3696 return retval; 3697 retval = dquot_initialize(new.dir); 3698 if (retval) 3699 return retval; 3700 3701 /* Initialize quotas before so that eventual writes go 3702 * in separate transaction */ 3703 if (new.inode) { 3704 retval = dquot_initialize(new.inode); 3705 if (retval) 3706 return retval; 3707 } 3708 3709 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); 3710 if (IS_ERR(old.bh)) 3711 return PTR_ERR(old.bh); 3712 /* 3713 * Check for inode number is _not_ due to possible IO errors. 3714 * We might rmdir the source, keep it as pwd of some process 3715 * and merrily kill the link to whatever was created under the 3716 * same name. Goodbye sticky bit ;-< 3717 */ 3718 retval = -ENOENT; 3719 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3720 goto end_rename; 3721 3722 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3723 &new.de, &new.inlined); 3724 if (IS_ERR(new.bh)) { 3725 retval = PTR_ERR(new.bh); 3726 new.bh = NULL; 3727 goto end_rename; 3728 } 3729 if (new.bh) { 3730 if (!new.inode) { 3731 brelse(new.bh); 3732 new.bh = NULL; 3733 } 3734 } 3735 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC)) 3736 ext4_alloc_da_blocks(old.inode); 3737 3738 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3739 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); 3740 if (!(flags & RENAME_WHITEOUT)) { 3741 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits); 3742 if (IS_ERR(handle)) { 3743 retval = PTR_ERR(handle); 3744 handle = NULL; 3745 goto end_rename; 3746 } 3747 } else { 3748 whiteout = ext4_whiteout_for_rename(&old, credits, &handle); 3749 if (IS_ERR(whiteout)) { 3750 retval = PTR_ERR(whiteout); 3751 whiteout = NULL; 3752 goto end_rename; 3753 } 3754 } 3755 3756 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3757 ext4_handle_sync(handle); 3758 3759 if (S_ISDIR(old.inode->i_mode)) { 3760 if (new.inode) { 3761 retval = -ENOTEMPTY; 3762 if (!ext4_empty_dir(new.inode)) 3763 goto end_rename; 3764 } else { 3765 retval = -EMLINK; 3766 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) 3767 goto end_rename; 3768 } 3769 retval = ext4_rename_dir_prepare(handle, &old); 3770 if (retval) 3771 goto end_rename; 3772 } 3773 /* 3774 * If we're renaming a file within an inline_data dir and adding or 3775 * setting the new dirent causes a conversion from inline_data to 3776 * extents/blockmap, we need to force the dirent delete code to 3777 * re-read the directory, or else we end up trying to delete a dirent 3778 * from what is now the extent tree root (or a block map). 3779 */ 3780 force_reread = (new.dir->i_ino == old.dir->i_ino && 3781 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA)); 3782 3783 old_file_type = old.de->file_type; 3784 if (whiteout) { 3785 /* 3786 * Do this before adding a new entry, so the old entry is sure 3787 * to be still pointing to the valid old entry. 3788 */ 3789 retval = ext4_setent(handle, &old, whiteout->i_ino, 3790 EXT4_FT_CHRDEV); 3791 if (retval) 3792 goto end_rename; 3793 ext4_mark_inode_dirty(handle, whiteout); 3794 } 3795 if (!new.bh) { 3796 retval = ext4_add_entry(handle, new.dentry, old.inode); 3797 if (retval) 3798 goto end_rename; 3799 } else { 3800 retval = ext4_setent(handle, &new, 3801 old.inode->i_ino, old_file_type); 3802 if (retval) 3803 goto end_rename; 3804 } 3805 if (force_reread) 3806 force_reread = !ext4_test_inode_flag(new.dir, 3807 EXT4_INODE_INLINE_DATA); 3808 3809 /* 3810 * Like most other Unix systems, set the ctime for inodes on a 3811 * rename. 3812 */ 3813 old.inode->i_ctime = current_time(old.inode); 3814 ext4_mark_inode_dirty(handle, old.inode); 3815 3816 if (!whiteout) { 3817 /* 3818 * ok, that's it 3819 */ 3820 ext4_rename_delete(handle, &old, force_reread); 3821 } 3822 3823 if (new.inode) { 3824 ext4_dec_count(handle, new.inode); 3825 new.inode->i_ctime = current_time(new.inode); 3826 } 3827 old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir); 3828 ext4_update_dx_flag(old.dir); 3829 if (old.dir_bh) { 3830 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3831 if (retval) 3832 goto end_rename; 3833 3834 ext4_dec_count(handle, old.dir); 3835 if (new.inode) { 3836 /* checked ext4_empty_dir above, can't have another 3837 * parent, ext4_dec_count() won't work for many-linked 3838 * dirs */ 3839 clear_nlink(new.inode); 3840 } else { 3841 ext4_inc_count(handle, new.dir); 3842 ext4_update_dx_flag(new.dir); 3843 ext4_mark_inode_dirty(handle, new.dir); 3844 } 3845 } 3846 ext4_mark_inode_dirty(handle, old.dir); 3847 if (new.inode) { 3848 ext4_mark_inode_dirty(handle, new.inode); 3849 if (!new.inode->i_nlink) 3850 ext4_orphan_add(handle, new.inode); 3851 } 3852 retval = 0; 3853 3854 end_rename: 3855 brelse(old.dir_bh); 3856 brelse(old.bh); 3857 brelse(new.bh); 3858 if (whiteout) { 3859 if (retval) 3860 drop_nlink(whiteout); 3861 unlock_new_inode(whiteout); 3862 iput(whiteout); 3863 } 3864 if (handle) 3865 ext4_journal_stop(handle); 3866 return retval; 3867 } 3868 3869 static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, 3870 struct inode *new_dir, struct dentry *new_dentry) 3871 { 3872 handle_t *handle = NULL; 3873 struct ext4_renament old = { 3874 .dir = old_dir, 3875 .dentry = old_dentry, 3876 .inode = d_inode(old_dentry), 3877 }; 3878 struct ext4_renament new = { 3879 .dir = new_dir, 3880 .dentry = new_dentry, 3881 .inode = d_inode(new_dentry), 3882 }; 3883 u8 new_file_type; 3884 int retval; 3885 struct timespec64 ctime; 3886 3887 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) && 3888 !projid_eq(EXT4_I(new_dir)->i_projid, 3889 EXT4_I(old_dentry->d_inode)->i_projid)) || 3890 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) && 3891 !projid_eq(EXT4_I(old_dir)->i_projid, 3892 EXT4_I(new_dentry->d_inode)->i_projid))) 3893 return -EXDEV; 3894 3895 retval = dquot_initialize(old.dir); 3896 if (retval) 3897 return retval; 3898 retval = dquot_initialize(new.dir); 3899 if (retval) 3900 return retval; 3901 3902 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, 3903 &old.de, &old.inlined); 3904 if (IS_ERR(old.bh)) 3905 return PTR_ERR(old.bh); 3906 /* 3907 * Check for inode number is _not_ due to possible IO errors. 3908 * We might rmdir the source, keep it as pwd of some process 3909 * and merrily kill the link to whatever was created under the 3910 * same name. Goodbye sticky bit ;-< 3911 */ 3912 retval = -ENOENT; 3913 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino) 3914 goto end_rename; 3915 3916 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name, 3917 &new.de, &new.inlined); 3918 if (IS_ERR(new.bh)) { 3919 retval = PTR_ERR(new.bh); 3920 new.bh = NULL; 3921 goto end_rename; 3922 } 3923 3924 /* RENAME_EXCHANGE case: old *and* new must both exist */ 3925 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino) 3926 goto end_rename; 3927 3928 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, 3929 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) + 3930 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2)); 3931 if (IS_ERR(handle)) { 3932 retval = PTR_ERR(handle); 3933 handle = NULL; 3934 goto end_rename; 3935 } 3936 3937 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir)) 3938 ext4_handle_sync(handle); 3939 3940 if (S_ISDIR(old.inode->i_mode)) { 3941 old.is_dir = true; 3942 retval = ext4_rename_dir_prepare(handle, &old); 3943 if (retval) 3944 goto end_rename; 3945 } 3946 if (S_ISDIR(new.inode->i_mode)) { 3947 new.is_dir = true; 3948 retval = ext4_rename_dir_prepare(handle, &new); 3949 if (retval) 3950 goto end_rename; 3951 } 3952 3953 /* 3954 * Other than the special case of overwriting a directory, parents' 3955 * nlink only needs to be modified if this is a cross directory rename. 3956 */ 3957 if (old.dir != new.dir && old.is_dir != new.is_dir) { 3958 old.dir_nlink_delta = old.is_dir ? -1 : 1; 3959 new.dir_nlink_delta = -old.dir_nlink_delta; 3960 retval = -EMLINK; 3961 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) || 3962 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir))) 3963 goto end_rename; 3964 } 3965 3966 new_file_type = new.de->file_type; 3967 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type); 3968 if (retval) 3969 goto end_rename; 3970 3971 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type); 3972 if (retval) 3973 goto end_rename; 3974 3975 /* 3976 * Like most other Unix systems, set the ctime for inodes on a 3977 * rename. 3978 */ 3979 ctime = current_time(old.inode); 3980 old.inode->i_ctime = ctime; 3981 new.inode->i_ctime = ctime; 3982 ext4_mark_inode_dirty(handle, old.inode); 3983 ext4_mark_inode_dirty(handle, new.inode); 3984 3985 if (old.dir_bh) { 3986 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); 3987 if (retval) 3988 goto end_rename; 3989 } 3990 if (new.dir_bh) { 3991 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino); 3992 if (retval) 3993 goto end_rename; 3994 } 3995 ext4_update_dir_count(handle, &old); 3996 ext4_update_dir_count(handle, &new); 3997 retval = 0; 3998 3999 end_rename: 4000 brelse(old.dir_bh); 4001 brelse(new.dir_bh); 4002 brelse(old.bh); 4003 brelse(new.bh); 4004 if (handle) 4005 ext4_journal_stop(handle); 4006 return retval; 4007 } 4008 4009 static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry, 4010 struct inode *new_dir, struct dentry *new_dentry, 4011 unsigned int flags) 4012 { 4013 int err; 4014 4015 if (unlikely(ext4_forced_shutdown(EXT4_SB(old_dir->i_sb)))) 4016 return -EIO; 4017 4018 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) 4019 return -EINVAL; 4020 4021 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry, 4022 flags); 4023 if (err) 4024 return err; 4025 4026 if (flags & RENAME_EXCHANGE) { 4027 return ext4_cross_rename(old_dir, old_dentry, 4028 new_dir, new_dentry); 4029 } 4030 4031 return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags); 4032 } 4033 4034 /* 4035 * directories can handle most operations... 4036 */ 4037 const struct inode_operations ext4_dir_inode_operations = { 4038 .create = ext4_create, 4039 .lookup = ext4_lookup, 4040 .link = ext4_link, 4041 .unlink = ext4_unlink, 4042 .symlink = ext4_symlink, 4043 .mkdir = ext4_mkdir, 4044 .rmdir = ext4_rmdir, 4045 .mknod = ext4_mknod, 4046 .tmpfile = ext4_tmpfile, 4047 .rename = ext4_rename2, 4048 .setattr = ext4_setattr, 4049 .getattr = ext4_getattr, 4050 .listxattr = ext4_listxattr, 4051 .get_acl = ext4_get_acl, 4052 .set_acl = ext4_set_acl, 4053 .fiemap = ext4_fiemap, 4054 }; 4055 4056 const struct inode_operations ext4_special_inode_operations = { 4057 .setattr = ext4_setattr, 4058 .getattr = ext4_getattr, 4059 .listxattr = ext4_listxattr, 4060 .get_acl = ext4_get_acl, 4061 .set_acl = ext4_set_acl, 4062 }; 4063