namei.c revision 734711abac46c8fee4d70cc9876ebc6d9edb4971
1/* 2 * linux/fs/ext3/namei.c 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Laboratoire MASI - Institut Blaise Pascal 7 * Universite Pierre et Marie Curie (Paris VI) 8 * 9 * from 10 * 11 * linux/fs/minix/namei.c 12 * 13 * Copyright (C) 1991, 1992 Linus Torvalds 14 * 15 * Big-endian to little-endian byte-swapping/bitmaps by 16 * David S. Miller (davem@caip.rutgers.edu), 1995 17 * Directory entry file type support and forward compatibility hooks 18 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998 19 * Hash Tree Directory indexing (c) 20 * Daniel Phillips, 2001 21 * Hash Tree Directory indexing porting 22 * Christopher Li, 2002 23 * Hash Tree Directory indexing cleanup 24 * Theodore Ts'o, 2002 25 */ 26 27#include <linux/fs.h> 28#include <linux/pagemap.h> 29#include <linux/jbd.h> 30#include <linux/time.h> 31#include <linux/ext3_fs.h> 32#include <linux/ext3_jbd.h> 33#include <linux/fcntl.h> 34#include <linux/stat.h> 35#include <linux/string.h> 36#include <linux/quotaops.h> 37#include <linux/buffer_head.h> 38#include <linux/bio.h> 39 40#include "namei.h" 41#include "xattr.h" 42#include "acl.h" 43 44/* 45 * define how far ahead to read directories while searching them. 46 */ 47#define NAMEI_RA_CHUNKS 2 48#define NAMEI_RA_BLOCKS 4 49#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) 50#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b)) 51 52static struct buffer_head *ext3_append(handle_t *handle, 53 struct inode *inode, 54 u32 *block, int *err) 55{ 56 struct buffer_head *bh; 57 58 *block = inode->i_size >> inode->i_sb->s_blocksize_bits; 59 60 bh = ext3_bread(handle, inode, *block, 1, err); 61 if (bh) { 62 inode->i_size += inode->i_sb->s_blocksize; 63 EXT3_I(inode)->i_disksize = inode->i_size; 64 *err = ext3_journal_get_write_access(handle, bh); 65 if (*err) { 66 brelse(bh); 67 bh = NULL; 68 } 69 } 70 return bh; 71} 72 73#ifndef assert 74#define assert(test) J_ASSERT(test) 75#endif 76 77#ifndef swap 78#define swap(x, y) do { typeof(x) z = x; x = y; y = z; } while (0) 79#endif 80 81#ifdef DX_DEBUG 82#define dxtrace(command) command 83#else 84#define dxtrace(command) 85#endif 86 87struct fake_dirent 88{ 89 __le32 inode; 90 __le16 rec_len; 91 u8 name_len; 92 u8 file_type; 93}; 94 95struct dx_countlimit 96{ 97 __le16 limit; 98 __le16 count; 99}; 100 101struct dx_entry 102{ 103 __le32 hash; 104 __le32 block; 105}; 106 107/* 108 * dx_root_info is laid out so that if it should somehow get overlaid by a 109 * dirent the two low bits of the hash version will be zero. Therefore, the 110 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 111 */ 112 113struct dx_root 114{ 115 struct fake_dirent dot; 116 char dot_name[4]; 117 struct fake_dirent dotdot; 118 char dotdot_name[4]; 119 struct dx_root_info 120 { 121 __le32 reserved_zero; 122 u8 hash_version; 123 u8 info_length; /* 8 */ 124 u8 indirect_levels; 125 u8 unused_flags; 126 } 127 info; 128 struct dx_entry entries[0]; 129}; 130 131struct dx_node 132{ 133 struct fake_dirent fake; 134 struct dx_entry entries[0]; 135}; 136 137 138struct dx_frame 139{ 140 struct buffer_head *bh; 141 struct dx_entry *entries; 142 struct dx_entry *at; 143}; 144 145struct dx_map_entry 146{ 147 u32 hash; 148 u16 offs; 149 u16 size; 150}; 151 152static inline unsigned dx_get_block (struct dx_entry *entry); 153static void dx_set_block (struct dx_entry *entry, unsigned value); 154static inline unsigned dx_get_hash (struct dx_entry *entry); 155static void dx_set_hash (struct dx_entry *entry, unsigned value); 156static unsigned dx_get_count (struct dx_entry *entries); 157static unsigned dx_get_limit (struct dx_entry *entries); 158static void dx_set_count (struct dx_entry *entries, unsigned value); 159static void dx_set_limit (struct dx_entry *entries, unsigned value); 160static unsigned dx_root_limit (struct inode *dir, unsigned infosize); 161static unsigned dx_node_limit (struct inode *dir); 162static struct dx_frame *dx_probe(struct qstr *entry, 163 struct inode *dir, 164 struct dx_hash_info *hinfo, 165 struct dx_frame *frame, 166 int *err); 167static void dx_release (struct dx_frame *frames); 168static int dx_make_map (struct ext3_dir_entry_2 *de, int size, 169 struct dx_hash_info *hinfo, struct dx_map_entry map[]); 170static void dx_sort_map(struct dx_map_entry *map, unsigned count); 171static struct ext3_dir_entry_2 *dx_move_dirents (char *from, char *to, 172 struct dx_map_entry *offsets, int count); 173static struct ext3_dir_entry_2* dx_pack_dirents (char *base, int size); 174static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block); 175static int ext3_htree_next_block(struct inode *dir, __u32 hash, 176 struct dx_frame *frame, 177 struct dx_frame *frames, 178 __u32 *start_hash); 179static struct buffer_head * ext3_dx_find_entry(struct inode *dir, 180 struct qstr *entry, struct ext3_dir_entry_2 **res_dir, 181 int *err); 182static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, 183 struct inode *inode); 184 185/* 186 * p is at least 6 bytes before the end of page 187 */ 188static inline struct ext3_dir_entry_2 * 189ext3_next_entry(struct ext3_dir_entry_2 *p) 190{ 191 return (struct ext3_dir_entry_2 *)((char *)p + 192 ext3_rec_len_from_disk(p->rec_len)); 193} 194 195/* 196 * Future: use high four bits of block for coalesce-on-delete flags 197 * Mask them off for now. 198 */ 199 200static inline unsigned dx_get_block (struct dx_entry *entry) 201{ 202 return le32_to_cpu(entry->block) & 0x00ffffff; 203} 204 205static inline void dx_set_block (struct dx_entry *entry, unsigned value) 206{ 207 entry->block = cpu_to_le32(value); 208} 209 210static inline unsigned dx_get_hash (struct dx_entry *entry) 211{ 212 return le32_to_cpu(entry->hash); 213} 214 215static inline void dx_set_hash (struct dx_entry *entry, unsigned value) 216{ 217 entry->hash = cpu_to_le32(value); 218} 219 220static inline unsigned dx_get_count (struct dx_entry *entries) 221{ 222 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 223} 224 225static inline unsigned dx_get_limit (struct dx_entry *entries) 226{ 227 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 228} 229 230static inline void dx_set_count (struct dx_entry *entries, unsigned value) 231{ 232 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 233} 234 235static inline void dx_set_limit (struct dx_entry *entries, unsigned value) 236{ 237 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 238} 239 240static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize) 241{ 242 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) - 243 EXT3_DIR_REC_LEN(2) - infosize; 244 return entry_space / sizeof(struct dx_entry); 245} 246 247static inline unsigned dx_node_limit (struct inode *dir) 248{ 249 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0); 250 return entry_space / sizeof(struct dx_entry); 251} 252 253/* 254 * Debug 255 */ 256#ifdef DX_DEBUG 257static void dx_show_index (char * label, struct dx_entry *entries) 258{ 259 int i, n = dx_get_count (entries); 260 printk("%s index ", label); 261 for (i = 0; i < n; i++) 262 { 263 printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i)); 264 } 265 printk("\n"); 266} 267 268struct stats 269{ 270 unsigned names; 271 unsigned space; 272 unsigned bcount; 273}; 274 275static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de, 276 int size, int show_names) 277{ 278 unsigned names = 0, space = 0; 279 char *base = (char *) de; 280 struct dx_hash_info h = *hinfo; 281 282 printk("names: "); 283 while ((char *) de < base + size) 284 { 285 if (de->inode) 286 { 287 if (show_names) 288 { 289 int len = de->name_len; 290 char *name = de->name; 291 while (len--) printk("%c", *name++); 292 ext3fs_dirhash(de->name, de->name_len, &h); 293 printk(":%x.%u ", h.hash, 294 ((char *) de - base)); 295 } 296 space += EXT3_DIR_REC_LEN(de->name_len); 297 names++; 298 } 299 de = ext3_next_entry(de); 300 } 301 printk("(%i)\n", names); 302 return (struct stats) { names, space, 1 }; 303} 304 305struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 306 struct dx_entry *entries, int levels) 307{ 308 unsigned blocksize = dir->i_sb->s_blocksize; 309 unsigned count = dx_get_count (entries), names = 0, space = 0, i; 310 unsigned bcount = 0; 311 struct buffer_head *bh; 312 int err; 313 printk("%i indexed blocks...\n", count); 314 for (i = 0; i < count; i++, entries++) 315 { 316 u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0; 317 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 318 struct stats stats; 319 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 320 if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue; 321 stats = levels? 322 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 323 dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0); 324 names += stats.names; 325 space += stats.space; 326 bcount += stats.bcount; 327 brelse (bh); 328 } 329 if (bcount) 330 printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ", 331 names, space/bcount,(space/bcount)*100/blocksize); 332 return (struct stats) { names, space, bcount}; 333} 334#endif /* DX_DEBUG */ 335 336/* 337 * Probe for a directory leaf block to search. 338 * 339 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 340 * error in the directory index, and the caller should fall back to 341 * searching the directory normally. The callers of dx_probe **MUST** 342 * check for this error code, and make sure it never gets reflected 343 * back to userspace. 344 */ 345static struct dx_frame * 346dx_probe(struct qstr *entry, struct inode *dir, 347 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err) 348{ 349 unsigned count, indirect; 350 struct dx_entry *at, *entries, *p, *q, *m; 351 struct dx_root *root; 352 struct buffer_head *bh; 353 struct dx_frame *frame = frame_in; 354 u32 hash; 355 356 frame->bh = NULL; 357 if (!(bh = ext3_bread (NULL,dir, 0, 0, err))) 358 goto fail; 359 root = (struct dx_root *) bh->b_data; 360 if (root->info.hash_version != DX_HASH_TEA && 361 root->info.hash_version != DX_HASH_HALF_MD4 && 362 root->info.hash_version != DX_HASH_LEGACY) { 363 ext3_warning(dir->i_sb, __func__, 364 "Unrecognised inode hash code %d", 365 root->info.hash_version); 366 brelse(bh); 367 *err = ERR_BAD_DX_DIR; 368 goto fail; 369 } 370 hinfo->hash_version = root->info.hash_version; 371 hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed; 372 if (entry) 373 ext3fs_dirhash(entry->name, entry->len, hinfo); 374 hash = hinfo->hash; 375 376 if (root->info.unused_flags & 1) { 377 ext3_warning(dir->i_sb, __func__, 378 "Unimplemented inode hash flags: %#06x", 379 root->info.unused_flags); 380 brelse(bh); 381 *err = ERR_BAD_DX_DIR; 382 goto fail; 383 } 384 385 if ((indirect = root->info.indirect_levels) > 1) { 386 ext3_warning(dir->i_sb, __func__, 387 "Unimplemented inode hash depth: %#06x", 388 root->info.indirect_levels); 389 brelse(bh); 390 *err = ERR_BAD_DX_DIR; 391 goto fail; 392 } 393 394 entries = (struct dx_entry *) (((char *)&root->info) + 395 root->info.info_length); 396 397 if (dx_get_limit(entries) != dx_root_limit(dir, 398 root->info.info_length)) { 399 ext3_warning(dir->i_sb, __func__, 400 "dx entry: limit != root limit"); 401 brelse(bh); 402 *err = ERR_BAD_DX_DIR; 403 goto fail; 404 } 405 406 dxtrace (printk("Look up %x", hash)); 407 while (1) 408 { 409 count = dx_get_count(entries); 410 if (!count || count > dx_get_limit(entries)) { 411 ext3_warning(dir->i_sb, __func__, 412 "dx entry: no count or count > limit"); 413 brelse(bh); 414 *err = ERR_BAD_DX_DIR; 415 goto fail2; 416 } 417 418 p = entries + 1; 419 q = entries + count - 1; 420 while (p <= q) 421 { 422 m = p + (q - p)/2; 423 dxtrace(printk(".")); 424 if (dx_get_hash(m) > hash) 425 q = m - 1; 426 else 427 p = m + 1; 428 } 429 430 if (0) // linear search cross check 431 { 432 unsigned n = count - 1; 433 at = entries; 434 while (n--) 435 { 436 dxtrace(printk(",")); 437 if (dx_get_hash(++at) > hash) 438 { 439 at--; 440 break; 441 } 442 } 443 assert (at == p - 1); 444 } 445 446 at = p - 1; 447 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at))); 448 frame->bh = bh; 449 frame->entries = entries; 450 frame->at = at; 451 if (!indirect--) return frame; 452 if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err))) 453 goto fail2; 454 at = entries = ((struct dx_node *) bh->b_data)->entries; 455 if (dx_get_limit(entries) != dx_node_limit (dir)) { 456 ext3_warning(dir->i_sb, __func__, 457 "dx entry: limit != node limit"); 458 brelse(bh); 459 *err = ERR_BAD_DX_DIR; 460 goto fail2; 461 } 462 frame++; 463 frame->bh = NULL; 464 } 465fail2: 466 while (frame >= frame_in) { 467 brelse(frame->bh); 468 frame--; 469 } 470fail: 471 if (*err == ERR_BAD_DX_DIR) 472 ext3_warning(dir->i_sb, __func__, 473 "Corrupt dir inode %ld, running e2fsck is " 474 "recommended.", dir->i_ino); 475 return NULL; 476} 477 478static void dx_release (struct dx_frame *frames) 479{ 480 if (frames[0].bh == NULL) 481 return; 482 483 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels) 484 brelse(frames[1].bh); 485 brelse(frames[0].bh); 486} 487 488/* 489 * This function increments the frame pointer to search the next leaf 490 * block, and reads in the necessary intervening nodes if the search 491 * should be necessary. Whether or not the search is necessary is 492 * controlled by the hash parameter. If the hash value is even, then 493 * the search is only continued if the next block starts with that 494 * hash value. This is used if we are searching for a specific file. 495 * 496 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 497 * 498 * This function returns 1 if the caller should continue to search, 499 * or 0 if it should not. If there is an error reading one of the 500 * index blocks, it will a negative error code. 501 * 502 * If start_hash is non-null, it will be filled in with the starting 503 * hash of the next page. 504 */ 505static int ext3_htree_next_block(struct inode *dir, __u32 hash, 506 struct dx_frame *frame, 507 struct dx_frame *frames, 508 __u32 *start_hash) 509{ 510 struct dx_frame *p; 511 struct buffer_head *bh; 512 int err, num_frames = 0; 513 __u32 bhash; 514 515 p = frame; 516 /* 517 * Find the next leaf page by incrementing the frame pointer. 518 * If we run out of entries in the interior node, loop around and 519 * increment pointer in the parent node. When we break out of 520 * this loop, num_frames indicates the number of interior 521 * nodes need to be read. 522 */ 523 while (1) { 524 if (++(p->at) < p->entries + dx_get_count(p->entries)) 525 break; 526 if (p == frames) 527 return 0; 528 num_frames++; 529 p--; 530 } 531 532 /* 533 * If the hash is 1, then continue only if the next page has a 534 * continuation hash of any value. This is used for readdir 535 * handling. Otherwise, check to see if the hash matches the 536 * desired contiuation hash. If it doesn't, return since 537 * there's no point to read in the successive index pages. 538 */ 539 bhash = dx_get_hash(p->at); 540 if (start_hash) 541 *start_hash = bhash; 542 if ((hash & 1) == 0) { 543 if ((bhash & ~1) != hash) 544 return 0; 545 } 546 /* 547 * If the hash is HASH_NB_ALWAYS, we always go to the next 548 * block so no check is necessary 549 */ 550 while (num_frames--) { 551 if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at), 552 0, &err))) 553 return err; /* Failure */ 554 p++; 555 brelse (p->bh); 556 p->bh = bh; 557 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 558 } 559 return 1; 560} 561 562 563/* 564 * This function fills a red-black tree with information from a 565 * directory block. It returns the number directory entries loaded 566 * into the tree. If there is an error it is returned in err. 567 */ 568static int htree_dirblock_to_tree(struct file *dir_file, 569 struct inode *dir, int block, 570 struct dx_hash_info *hinfo, 571 __u32 start_hash, __u32 start_minor_hash) 572{ 573 struct buffer_head *bh; 574 struct ext3_dir_entry_2 *de, *top; 575 int err, count = 0; 576 577 dxtrace(printk("In htree dirblock_to_tree: block %d\n", block)); 578 if (!(bh = ext3_bread (NULL, dir, block, 0, &err))) 579 return err; 580 581 de = (struct ext3_dir_entry_2 *) bh->b_data; 582 top = (struct ext3_dir_entry_2 *) ((char *) de + 583 dir->i_sb->s_blocksize - 584 EXT3_DIR_REC_LEN(0)); 585 for (; de < top; de = ext3_next_entry(de)) { 586 if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh, 587 (block<<EXT3_BLOCK_SIZE_BITS(dir->i_sb)) 588 +((char *)de - bh->b_data))) { 589 /* On error, skip the f_pos to the next block. */ 590 dir_file->f_pos = (dir_file->f_pos | 591 (dir->i_sb->s_blocksize - 1)) + 1; 592 brelse (bh); 593 return count; 594 } 595 ext3fs_dirhash(de->name, de->name_len, hinfo); 596 if ((hinfo->hash < start_hash) || 597 ((hinfo->hash == start_hash) && 598 (hinfo->minor_hash < start_minor_hash))) 599 continue; 600 if (de->inode == 0) 601 continue; 602 if ((err = ext3_htree_store_dirent(dir_file, 603 hinfo->hash, hinfo->minor_hash, de)) != 0) { 604 brelse(bh); 605 return err; 606 } 607 count++; 608 } 609 brelse(bh); 610 return count; 611} 612 613 614/* 615 * This function fills a red-black tree with information from a 616 * directory. We start scanning the directory in hash order, starting 617 * at start_hash and start_minor_hash. 618 * 619 * This function returns the number of entries inserted into the tree, 620 * or a negative error code. 621 */ 622int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash, 623 __u32 start_minor_hash, __u32 *next_hash) 624{ 625 struct dx_hash_info hinfo; 626 struct ext3_dir_entry_2 *de; 627 struct dx_frame frames[2], *frame; 628 struct inode *dir; 629 int block, err; 630 int count = 0; 631 int ret; 632 __u32 hashval; 633 634 dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash, 635 start_minor_hash)); 636 dir = dir_file->f_path.dentry->d_inode; 637 if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) { 638 hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 639 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 640 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 641 start_hash, start_minor_hash); 642 *next_hash = ~0; 643 return count; 644 } 645 hinfo.hash = start_hash; 646 hinfo.minor_hash = 0; 647 frame = dx_probe(NULL, dir_file->f_path.dentry->d_inode, &hinfo, frames, &err); 648 if (!frame) 649 return err; 650 651 /* Add '.' and '..' from the htree header */ 652 if (!start_hash && !start_minor_hash) { 653 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 654 if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0) 655 goto errout; 656 count++; 657 } 658 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 659 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 660 de = ext3_next_entry(de); 661 if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0) 662 goto errout; 663 count++; 664 } 665 666 while (1) { 667 block = dx_get_block(frame->at); 668 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 669 start_hash, start_minor_hash); 670 if (ret < 0) { 671 err = ret; 672 goto errout; 673 } 674 count += ret; 675 hashval = ~0; 676 ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS, 677 frame, frames, &hashval); 678 *next_hash = hashval; 679 if (ret < 0) { 680 err = ret; 681 goto errout; 682 } 683 /* 684 * Stop if: (a) there are no more entries, or 685 * (b) we have inserted at least one entry and the 686 * next hash value is not a continuation 687 */ 688 if ((ret == 0) || 689 (count && ((hashval & 1) == 0))) 690 break; 691 } 692 dx_release(frames); 693 dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n", 694 count, *next_hash)); 695 return count; 696errout: 697 dx_release(frames); 698 return (err); 699} 700 701 702/* 703 * Directory block splitting, compacting 704 */ 705 706/* 707 * Create map of hash values, offsets, and sizes, stored at end of block. 708 * Returns number of entries mapped. 709 */ 710static int dx_make_map (struct ext3_dir_entry_2 *de, int size, 711 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail) 712{ 713 int count = 0; 714 char *base = (char *) de; 715 struct dx_hash_info h = *hinfo; 716 717 while ((char *) de < base + size) 718 { 719 if (de->name_len && de->inode) { 720 ext3fs_dirhash(de->name, de->name_len, &h); 721 map_tail--; 722 map_tail->hash = h.hash; 723 map_tail->offs = (u16) ((char *) de - base); 724 map_tail->size = le16_to_cpu(de->rec_len); 725 count++; 726 cond_resched(); 727 } 728 /* XXX: do we need to check rec_len == 0 case? -Chris */ 729 de = ext3_next_entry(de); 730 } 731 return count; 732} 733 734/* Sort map by hash value */ 735static void dx_sort_map (struct dx_map_entry *map, unsigned count) 736{ 737 struct dx_map_entry *p, *q, *top = map + count - 1; 738 int more; 739 /* Combsort until bubble sort doesn't suck */ 740 while (count > 2) 741 { 742 count = count*10/13; 743 if (count - 9 < 2) /* 9, 10 -> 11 */ 744 count = 11; 745 for (p = top, q = p - count; q >= map; p--, q--) 746 if (p->hash < q->hash) 747 swap(*p, *q); 748 } 749 /* Garden variety bubble sort */ 750 do { 751 more = 0; 752 q = top; 753 while (q-- > map) 754 { 755 if (q[1].hash >= q[0].hash) 756 continue; 757 swap(*(q+1), *q); 758 more = 1; 759 } 760 } while(more); 761} 762 763static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block) 764{ 765 struct dx_entry *entries = frame->entries; 766 struct dx_entry *old = frame->at, *new = old + 1; 767 int count = dx_get_count(entries); 768 769 assert(count < dx_get_limit(entries)); 770 assert(old < entries + count); 771 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 772 dx_set_hash(new, hash); 773 dx_set_block(new, block); 774 dx_set_count(entries, count + 1); 775} 776 777static void ext3_update_dx_flag(struct inode *inode) 778{ 779 if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb, 780 EXT3_FEATURE_COMPAT_DIR_INDEX)) 781 EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL; 782} 783 784/* 785 * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure. 786 * 787 * `len <= EXT3_NAME_LEN' is guaranteed by caller. 788 * `de != NULL' is guaranteed by caller. 789 */ 790static inline int ext3_match (int len, const char * const name, 791 struct ext3_dir_entry_2 * de) 792{ 793 if (len != de->name_len) 794 return 0; 795 if (!de->inode) 796 return 0; 797 return !memcmp(name, de->name, len); 798} 799 800/* 801 * Returns 0 if not found, -1 on failure, and 1 on success 802 */ 803static inline int search_dirblock(struct buffer_head * bh, 804 struct inode *dir, 805 struct qstr *child, 806 unsigned long offset, 807 struct ext3_dir_entry_2 ** res_dir) 808{ 809 struct ext3_dir_entry_2 * de; 810 char * dlimit; 811 int de_len; 812 const char *name = child->name; 813 int namelen = child->len; 814 815 de = (struct ext3_dir_entry_2 *) bh->b_data; 816 dlimit = bh->b_data + dir->i_sb->s_blocksize; 817 while ((char *) de < dlimit) { 818 /* this code is executed quadratically often */ 819 /* do minimal checking `by hand' */ 820 821 if ((char *) de + namelen <= dlimit && 822 ext3_match (namelen, name, de)) { 823 /* found a match - just to be sure, do a full check */ 824 if (!ext3_check_dir_entry("ext3_find_entry", 825 dir, de, bh, offset)) 826 return -1; 827 *res_dir = de; 828 return 1; 829 } 830 /* prevent looping on a bad block */ 831 de_len = ext3_rec_len_from_disk(de->rec_len); 832 if (de_len <= 0) 833 return -1; 834 offset += de_len; 835 de = (struct ext3_dir_entry_2 *) ((char *) de + de_len); 836 } 837 return 0; 838} 839 840 841/* 842 * ext3_find_entry() 843 * 844 * finds an entry in the specified directory with the wanted name. It 845 * returns the cache buffer in which the entry was found, and the entry 846 * itself (as a parameter - res_dir). It does NOT read the inode of the 847 * entry - you'll have to do that yourself if you want to. 848 * 849 * The returned buffer_head has ->b_count elevated. The caller is expected 850 * to brelse() it when appropriate. 851 */ 852static struct buffer_head *ext3_find_entry(struct inode *dir, 853 struct qstr *entry, 854 struct ext3_dir_entry_2 **res_dir) 855{ 856 struct super_block * sb; 857 struct buffer_head * bh_use[NAMEI_RA_SIZE]; 858 struct buffer_head * bh, *ret = NULL; 859 unsigned long start, block, b; 860 int ra_max = 0; /* Number of bh's in the readahead 861 buffer, bh_use[] */ 862 int ra_ptr = 0; /* Current index into readahead 863 buffer */ 864 int num = 0; 865 int nblocks, i, err; 866 int namelen; 867 868 *res_dir = NULL; 869 sb = dir->i_sb; 870 namelen = entry->len; 871 if (namelen > EXT3_NAME_LEN) 872 return NULL; 873 if (is_dx(dir)) { 874 bh = ext3_dx_find_entry(dir, entry, res_dir, &err); 875 /* 876 * On success, or if the error was file not found, 877 * return. Otherwise, fall back to doing a search the 878 * old fashioned way. 879 */ 880 if (bh || (err != ERR_BAD_DX_DIR)) 881 return bh; 882 dxtrace(printk("ext3_find_entry: dx failed, falling back\n")); 883 } 884 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); 885 start = EXT3_I(dir)->i_dir_start_lookup; 886 if (start >= nblocks) 887 start = 0; 888 block = start; 889restart: 890 do { 891 /* 892 * We deal with the read-ahead logic here. 893 */ 894 if (ra_ptr >= ra_max) { 895 /* Refill the readahead buffer */ 896 ra_ptr = 0; 897 b = block; 898 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) { 899 /* 900 * Terminate if we reach the end of the 901 * directory and must wrap, or if our 902 * search has finished at this block. 903 */ 904 if (b >= nblocks || (num && block == start)) { 905 bh_use[ra_max] = NULL; 906 break; 907 } 908 num++; 909 bh = ext3_getblk(NULL, dir, b++, 0, &err); 910 bh_use[ra_max] = bh; 911 if (bh) 912 ll_rw_block(READ_META, 1, &bh); 913 } 914 } 915 if ((bh = bh_use[ra_ptr++]) == NULL) 916 goto next; 917 wait_on_buffer(bh); 918 if (!buffer_uptodate(bh)) { 919 /* read error, skip block & hope for the best */ 920 ext3_error(sb, __func__, "reading directory #%lu " 921 "offset %lu", dir->i_ino, block); 922 brelse(bh); 923 goto next; 924 } 925 i = search_dirblock(bh, dir, entry, 926 block << EXT3_BLOCK_SIZE_BITS(sb), res_dir); 927 if (i == 1) { 928 EXT3_I(dir)->i_dir_start_lookup = block; 929 ret = bh; 930 goto cleanup_and_exit; 931 } else { 932 brelse(bh); 933 if (i < 0) 934 goto cleanup_and_exit; 935 } 936 next: 937 if (++block >= nblocks) 938 block = 0; 939 } while (block != start); 940 941 /* 942 * If the directory has grown while we were searching, then 943 * search the last part of the directory before giving up. 944 */ 945 block = nblocks; 946 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); 947 if (block < nblocks) { 948 start = 0; 949 goto restart; 950 } 951 952cleanup_and_exit: 953 /* Clean up the read-ahead blocks */ 954 for (; ra_ptr < ra_max; ra_ptr++) 955 brelse (bh_use[ra_ptr]); 956 return ret; 957} 958 959static struct buffer_head * ext3_dx_find_entry(struct inode *dir, 960 struct qstr *entry, struct ext3_dir_entry_2 **res_dir, 961 int *err) 962{ 963 struct super_block * sb; 964 struct dx_hash_info hinfo; 965 u32 hash; 966 struct dx_frame frames[2], *frame; 967 struct ext3_dir_entry_2 *de, *top; 968 struct buffer_head *bh; 969 unsigned long block; 970 int retval; 971 int namelen = entry->len; 972 const u8 *name = entry->name; 973 974 sb = dir->i_sb; 975 /* NFS may look up ".." - look at dx_root directory block */ 976 if (namelen > 2 || name[0] != '.'|| (namelen == 2 && name[1] != '.')) { 977 if (!(frame = dx_probe(entry, dir, &hinfo, frames, err))) 978 return NULL; 979 } else { 980 frame = frames; 981 frame->bh = NULL; /* for dx_release() */ 982 frame->at = (struct dx_entry *)frames; /* hack for zero entry*/ 983 dx_set_block(frame->at, 0); /* dx_root block is 0 */ 984 } 985 hash = hinfo.hash; 986 do { 987 block = dx_get_block(frame->at); 988 if (!(bh = ext3_bread (NULL,dir, block, 0, err))) 989 goto errout; 990 de = (struct ext3_dir_entry_2 *) bh->b_data; 991 top = (struct ext3_dir_entry_2 *) ((char *) de + sb->s_blocksize - 992 EXT3_DIR_REC_LEN(0)); 993 for (; de < top; de = ext3_next_entry(de)) { 994 int off = (block << EXT3_BLOCK_SIZE_BITS(sb)) 995 + ((char *) de - bh->b_data); 996 997 if (!ext3_check_dir_entry(__func__, dir, de, bh, off)) { 998 brelse(bh); 999 *err = ERR_BAD_DX_DIR; 1000 goto errout; 1001 } 1002 1003 if (ext3_match(namelen, name, de)) { 1004 *res_dir = de; 1005 dx_release(frames); 1006 return bh; 1007 } 1008 } 1009 brelse (bh); 1010 /* Check to see if we should continue to search */ 1011 retval = ext3_htree_next_block(dir, hash, frame, 1012 frames, NULL); 1013 if (retval < 0) { 1014 ext3_warning(sb, __func__, 1015 "error reading index page in directory #%lu", 1016 dir->i_ino); 1017 *err = retval; 1018 goto errout; 1019 } 1020 } while (retval == 1); 1021 1022 *err = -ENOENT; 1023errout: 1024 dxtrace(printk("%s not found\n", name)); 1025 dx_release (frames); 1026 return NULL; 1027} 1028 1029static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) 1030{ 1031 struct inode * inode; 1032 struct ext3_dir_entry_2 * de; 1033 struct buffer_head * bh; 1034 1035 if (dentry->d_name.len > EXT3_NAME_LEN) 1036 return ERR_PTR(-ENAMETOOLONG); 1037 1038 bh = ext3_find_entry(dir, &dentry->d_name, &de); 1039 inode = NULL; 1040 if (bh) { 1041 unsigned long ino = le32_to_cpu(de->inode); 1042 brelse (bh); 1043 if (!ext3_valid_inum(dir->i_sb, ino)) { 1044 ext3_error(dir->i_sb, "ext3_lookup", 1045 "bad inode number: %lu", ino); 1046 return ERR_PTR(-EIO); 1047 } 1048 inode = ext3_iget(dir->i_sb, ino); 1049 if (IS_ERR(inode)) 1050 return ERR_CAST(inode); 1051 } 1052 return d_splice_alias(inode, dentry); 1053} 1054 1055 1056struct dentry *ext3_get_parent(struct dentry *child) 1057{ 1058 unsigned long ino; 1059 struct qstr dotdot = {.name = "..", .len = 2}; 1060 struct ext3_dir_entry_2 * de; 1061 struct buffer_head *bh; 1062 1063 bh = ext3_find_entry(child->d_inode, &dotdot, &de); 1064 if (!bh) 1065 return ERR_PTR(-ENOENT); 1066 ino = le32_to_cpu(de->inode); 1067 brelse(bh); 1068 1069 if (!ext3_valid_inum(child->d_inode->i_sb, ino)) { 1070 ext3_error(child->d_inode->i_sb, "ext3_get_parent", 1071 "bad inode number: %lu", ino); 1072 return ERR_PTR(-EIO); 1073 } 1074 1075 return d_obtain_alias(ext3_iget(child->d_inode->i_sb, ino)); 1076} 1077 1078#define S_SHIFT 12 1079static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = { 1080 [S_IFREG >> S_SHIFT] = EXT3_FT_REG_FILE, 1081 [S_IFDIR >> S_SHIFT] = EXT3_FT_DIR, 1082 [S_IFCHR >> S_SHIFT] = EXT3_FT_CHRDEV, 1083 [S_IFBLK >> S_SHIFT] = EXT3_FT_BLKDEV, 1084 [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO, 1085 [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK, 1086 [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK, 1087}; 1088 1089static inline void ext3_set_de_type(struct super_block *sb, 1090 struct ext3_dir_entry_2 *de, 1091 umode_t mode) { 1092 if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE)) 1093 de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; 1094} 1095 1096/* 1097 * Move count entries from end of map between two memory locations. 1098 * Returns pointer to last entry moved. 1099 */ 1100static struct ext3_dir_entry_2 * 1101dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) 1102{ 1103 unsigned rec_len = 0; 1104 1105 while (count--) { 1106 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs); 1107 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1108 memcpy (to, de, rec_len); 1109 ((struct ext3_dir_entry_2 *) to)->rec_len = 1110 ext3_rec_len_to_disk(rec_len); 1111 de->inode = 0; 1112 map++; 1113 to += rec_len; 1114 } 1115 return (struct ext3_dir_entry_2 *) (to - rec_len); 1116} 1117 1118/* 1119 * Compact each dir entry in the range to the minimal rec_len. 1120 * Returns pointer to last entry in range. 1121 */ 1122static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size) 1123{ 1124 struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base; 1125 unsigned rec_len = 0; 1126 1127 prev = to = de; 1128 while ((char*)de < base + size) { 1129 next = ext3_next_entry(de); 1130 if (de->inode && de->name_len) { 1131 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1132 if (de > to) 1133 memmove(to, de, rec_len); 1134 to->rec_len = ext3_rec_len_to_disk(rec_len); 1135 prev = to; 1136 to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len); 1137 } 1138 de = next; 1139 } 1140 return prev; 1141} 1142 1143/* 1144 * Split a full leaf block to make room for a new dir entry. 1145 * Allocate a new block, and move entries so that they are approx. equally full. 1146 * Returns pointer to de in block into which the new entry will be inserted. 1147 */ 1148static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1149 struct buffer_head **bh,struct dx_frame *frame, 1150 struct dx_hash_info *hinfo, int *error) 1151{ 1152 unsigned blocksize = dir->i_sb->s_blocksize; 1153 unsigned count, continued; 1154 struct buffer_head *bh2; 1155 u32 newblock; 1156 u32 hash2; 1157 struct dx_map_entry *map; 1158 char *data1 = (*bh)->b_data, *data2; 1159 unsigned split, move, size, i; 1160 struct ext3_dir_entry_2 *de = NULL, *de2; 1161 int err = 0; 1162 1163 bh2 = ext3_append (handle, dir, &newblock, &err); 1164 if (!(bh2)) { 1165 brelse(*bh); 1166 *bh = NULL; 1167 goto errout; 1168 } 1169 1170 BUFFER_TRACE(*bh, "get_write_access"); 1171 err = ext3_journal_get_write_access(handle, *bh); 1172 if (err) 1173 goto journal_error; 1174 1175 BUFFER_TRACE(frame->bh, "get_write_access"); 1176 err = ext3_journal_get_write_access(handle, frame->bh); 1177 if (err) 1178 goto journal_error; 1179 1180 data2 = bh2->b_data; 1181 1182 /* create map in the end of data2 block */ 1183 map = (struct dx_map_entry *) (data2 + blocksize); 1184 count = dx_make_map ((struct ext3_dir_entry_2 *) data1, 1185 blocksize, hinfo, map); 1186 map -= count; 1187 dx_sort_map (map, count); 1188 /* Split the existing block in the middle, size-wise */ 1189 size = 0; 1190 move = 0; 1191 for (i = count-1; i >= 0; i--) { 1192 /* is more than half of this entry in 2nd half of the block? */ 1193 if (size + map[i].size/2 > blocksize/2) 1194 break; 1195 size += map[i].size; 1196 move++; 1197 } 1198 /* map index at which we will split */ 1199 split = count - move; 1200 hash2 = map[split].hash; 1201 continued = hash2 == map[split - 1].hash; 1202 dxtrace(printk("Split block %i at %x, %i/%i\n", 1203 dx_get_block(frame->at), hash2, split, count-split)); 1204 1205 /* Fancy dance to stay within two buffers */ 1206 de2 = dx_move_dirents(data1, data2, map + split, count - split); 1207 de = dx_pack_dirents(data1,blocksize); 1208 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de); 1209 de2->rec_len = ext3_rec_len_to_disk(data2 + blocksize - (char *) de2); 1210 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1)); 1211 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1)); 1212 1213 /* Which block gets the new entry? */ 1214 if (hinfo->hash >= hash2) 1215 { 1216 swap(*bh, bh2); 1217 de = de2; 1218 } 1219 dx_insert_block (frame, hash2 + continued, newblock); 1220 err = ext3_journal_dirty_metadata (handle, bh2); 1221 if (err) 1222 goto journal_error; 1223 err = ext3_journal_dirty_metadata (handle, frame->bh); 1224 if (err) 1225 goto journal_error; 1226 brelse (bh2); 1227 dxtrace(dx_show_index ("frame", frame->entries)); 1228 return de; 1229 1230journal_error: 1231 brelse(*bh); 1232 brelse(bh2); 1233 *bh = NULL; 1234 ext3_std_error(dir->i_sb, err); 1235errout: 1236 *error = err; 1237 return NULL; 1238} 1239 1240 1241/* 1242 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1243 * it points to a directory entry which is guaranteed to be large 1244 * enough for new directory entry. If de is NULL, then 1245 * add_dirent_to_buf will attempt search the directory block for 1246 * space. It will return -ENOSPC if no space is available, and -EIO 1247 * and -EEXIST if directory entry already exists. 1248 * 1249 * NOTE! bh is NOT released in the case where ENOSPC is returned. In 1250 * all other cases bh is released. 1251 */ 1252static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, 1253 struct inode *inode, struct ext3_dir_entry_2 *de, 1254 struct buffer_head * bh) 1255{ 1256 struct inode *dir = dentry->d_parent->d_inode; 1257 const char *name = dentry->d_name.name; 1258 int namelen = dentry->d_name.len; 1259 unsigned long offset = 0; 1260 unsigned short reclen; 1261 int nlen, rlen, err; 1262 char *top; 1263 1264 reclen = EXT3_DIR_REC_LEN(namelen); 1265 if (!de) { 1266 de = (struct ext3_dir_entry_2 *)bh->b_data; 1267 top = bh->b_data + dir->i_sb->s_blocksize - reclen; 1268 while ((char *) de <= top) { 1269 if (!ext3_check_dir_entry("ext3_add_entry", dir, de, 1270 bh, offset)) { 1271 brelse (bh); 1272 return -EIO; 1273 } 1274 if (ext3_match (namelen, name, de)) { 1275 brelse (bh); 1276 return -EEXIST; 1277 } 1278 nlen = EXT3_DIR_REC_LEN(de->name_len); 1279 rlen = ext3_rec_len_from_disk(de->rec_len); 1280 if ((de->inode? rlen - nlen: rlen) >= reclen) 1281 break; 1282 de = (struct ext3_dir_entry_2 *)((char *)de + rlen); 1283 offset += rlen; 1284 } 1285 if ((char *) de > top) 1286 return -ENOSPC; 1287 } 1288 BUFFER_TRACE(bh, "get_write_access"); 1289 err = ext3_journal_get_write_access(handle, bh); 1290 if (err) { 1291 ext3_std_error(dir->i_sb, err); 1292 brelse(bh); 1293 return err; 1294 } 1295 1296 /* By now the buffer is marked for journaling */ 1297 nlen = EXT3_DIR_REC_LEN(de->name_len); 1298 rlen = ext3_rec_len_from_disk(de->rec_len); 1299 if (de->inode) { 1300 struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen); 1301 de1->rec_len = ext3_rec_len_to_disk(rlen - nlen); 1302 de->rec_len = ext3_rec_len_to_disk(nlen); 1303 de = de1; 1304 } 1305 de->file_type = EXT3_FT_UNKNOWN; 1306 if (inode) { 1307 de->inode = cpu_to_le32(inode->i_ino); 1308 ext3_set_de_type(dir->i_sb, de, inode->i_mode); 1309 } else 1310 de->inode = 0; 1311 de->name_len = namelen; 1312 memcpy (de->name, name, namelen); 1313 /* 1314 * XXX shouldn't update any times until successful 1315 * completion of syscall, but too many callers depend 1316 * on this. 1317 * 1318 * XXX similarly, too many callers depend on 1319 * ext3_new_inode() setting the times, but error 1320 * recovery deletes the inode, so the worst that can 1321 * happen is that the times are slightly out of date 1322 * and/or different from the directory change time. 1323 */ 1324 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; 1325 ext3_update_dx_flag(dir); 1326 dir->i_version++; 1327 ext3_mark_inode_dirty(handle, dir); 1328 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1329 err = ext3_journal_dirty_metadata(handle, bh); 1330 if (err) 1331 ext3_std_error(dir->i_sb, err); 1332 brelse(bh); 1333 return 0; 1334} 1335 1336/* 1337 * This converts a one block unindexed directory to a 3 block indexed 1338 * directory, and adds the dentry to the indexed directory. 1339 */ 1340static int make_indexed_dir(handle_t *handle, struct dentry *dentry, 1341 struct inode *inode, struct buffer_head *bh) 1342{ 1343 struct inode *dir = dentry->d_parent->d_inode; 1344 const char *name = dentry->d_name.name; 1345 int namelen = dentry->d_name.len; 1346 struct buffer_head *bh2; 1347 struct dx_root *root; 1348 struct dx_frame frames[2], *frame; 1349 struct dx_entry *entries; 1350 struct ext3_dir_entry_2 *de, *de2; 1351 char *data1, *top; 1352 unsigned len; 1353 int retval; 1354 unsigned blocksize; 1355 struct dx_hash_info hinfo; 1356 u32 block; 1357 struct fake_dirent *fde; 1358 1359 blocksize = dir->i_sb->s_blocksize; 1360 dxtrace(printk("Creating index\n")); 1361 retval = ext3_journal_get_write_access(handle, bh); 1362 if (retval) { 1363 ext3_std_error(dir->i_sb, retval); 1364 brelse(bh); 1365 return retval; 1366 } 1367 root = (struct dx_root *) bh->b_data; 1368 1369 bh2 = ext3_append (handle, dir, &block, &retval); 1370 if (!(bh2)) { 1371 brelse(bh); 1372 return retval; 1373 } 1374 EXT3_I(dir)->i_flags |= EXT3_INDEX_FL; 1375 data1 = bh2->b_data; 1376 1377 /* The 0th block becomes the root, move the dirents out */ 1378 fde = &root->dotdot; 1379 de = (struct ext3_dir_entry_2 *)((char *)fde + 1380 ext3_rec_len_from_disk(fde->rec_len)); 1381 len = ((char *) root) + blocksize - (char *) de; 1382 memcpy (data1, de, len); 1383 de = (struct ext3_dir_entry_2 *) data1; 1384 top = data1 + len; 1385 while ((char *)(de2 = ext3_next_entry(de)) < top) 1386 de = de2; 1387 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de); 1388 /* Initialize the root; the dot dirents already exist */ 1389 de = (struct ext3_dir_entry_2 *) (&root->dotdot); 1390 de->rec_len = ext3_rec_len_to_disk(blocksize - EXT3_DIR_REC_LEN(2)); 1391 memset (&root->info, 0, sizeof(root->info)); 1392 root->info.info_length = sizeof(root->info); 1393 root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 1394 entries = root->entries; 1395 dx_set_block (entries, 1); 1396 dx_set_count (entries, 1); 1397 dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info))); 1398 1399 /* Initialize as for dx_probe */ 1400 hinfo.hash_version = root->info.hash_version; 1401 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 1402 ext3fs_dirhash(name, namelen, &hinfo); 1403 frame = frames; 1404 frame->entries = entries; 1405 frame->at = entries; 1406 frame->bh = bh; 1407 bh = bh2; 1408 de = do_split(handle,dir, &bh, frame, &hinfo, &retval); 1409 dx_release (frames); 1410 if (!(de)) 1411 return retval; 1412 1413 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1414} 1415 1416/* 1417 * ext3_add_entry() 1418 * 1419 * adds a file entry to the specified directory, using the same 1420 * semantics as ext3_find_entry(). It returns NULL if it failed. 1421 * 1422 * NOTE!! The inode part of 'de' is left at 0 - which means you 1423 * may not sleep between calling this and putting something into 1424 * the entry, as someone else might have used it while you slept. 1425 */ 1426static int ext3_add_entry (handle_t *handle, struct dentry *dentry, 1427 struct inode *inode) 1428{ 1429 struct inode *dir = dentry->d_parent->d_inode; 1430 unsigned long offset; 1431 struct buffer_head * bh; 1432 struct ext3_dir_entry_2 *de; 1433 struct super_block * sb; 1434 int retval; 1435 int dx_fallback=0; 1436 unsigned blocksize; 1437 u32 block, blocks; 1438 1439 sb = dir->i_sb; 1440 blocksize = sb->s_blocksize; 1441 if (!dentry->d_name.len) 1442 return -EINVAL; 1443 if (is_dx(dir)) { 1444 retval = ext3_dx_add_entry(handle, dentry, inode); 1445 if (!retval || (retval != ERR_BAD_DX_DIR)) 1446 return retval; 1447 EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL; 1448 dx_fallback++; 1449 ext3_mark_inode_dirty(handle, dir); 1450 } 1451 blocks = dir->i_size >> sb->s_blocksize_bits; 1452 for (block = 0, offset = 0; block < blocks; block++) { 1453 bh = ext3_bread(handle, dir, block, 0, &retval); 1454 if(!bh) 1455 return retval; 1456 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1457 if (retval != -ENOSPC) 1458 return retval; 1459 1460 if (blocks == 1 && !dx_fallback && 1461 EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) 1462 return make_indexed_dir(handle, dentry, inode, bh); 1463 brelse(bh); 1464 } 1465 bh = ext3_append(handle, dir, &block, &retval); 1466 if (!bh) 1467 return retval; 1468 de = (struct ext3_dir_entry_2 *) bh->b_data; 1469 de->inode = 0; 1470 de->rec_len = ext3_rec_len_to_disk(blocksize); 1471 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1472} 1473 1474/* 1475 * Returns 0 for success, or a negative error value 1476 */ 1477static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, 1478 struct inode *inode) 1479{ 1480 struct dx_frame frames[2], *frame; 1481 struct dx_entry *entries, *at; 1482 struct dx_hash_info hinfo; 1483 struct buffer_head * bh; 1484 struct inode *dir = dentry->d_parent->d_inode; 1485 struct super_block * sb = dir->i_sb; 1486 struct ext3_dir_entry_2 *de; 1487 int err; 1488 1489 frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err); 1490 if (!frame) 1491 return err; 1492 entries = frame->entries; 1493 at = frame->at; 1494 1495 if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err))) 1496 goto cleanup; 1497 1498 BUFFER_TRACE(bh, "get_write_access"); 1499 err = ext3_journal_get_write_access(handle, bh); 1500 if (err) 1501 goto journal_error; 1502 1503 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1504 if (err != -ENOSPC) { 1505 bh = NULL; 1506 goto cleanup; 1507 } 1508 1509 /* Block full, should compress but for now just split */ 1510 dxtrace(printk("using %u of %u node entries\n", 1511 dx_get_count(entries), dx_get_limit(entries))); 1512 /* Need to split index? */ 1513 if (dx_get_count(entries) == dx_get_limit(entries)) { 1514 u32 newblock; 1515 unsigned icount = dx_get_count(entries); 1516 int levels = frame - frames; 1517 struct dx_entry *entries2; 1518 struct dx_node *node2; 1519 struct buffer_head *bh2; 1520 1521 if (levels && (dx_get_count(frames->entries) == 1522 dx_get_limit(frames->entries))) { 1523 ext3_warning(sb, __func__, 1524 "Directory index full!"); 1525 err = -ENOSPC; 1526 goto cleanup; 1527 } 1528 bh2 = ext3_append (handle, dir, &newblock, &err); 1529 if (!(bh2)) 1530 goto cleanup; 1531 node2 = (struct dx_node *)(bh2->b_data); 1532 entries2 = node2->entries; 1533 node2->fake.rec_len = ext3_rec_len_to_disk(sb->s_blocksize); 1534 node2->fake.inode = 0; 1535 BUFFER_TRACE(frame->bh, "get_write_access"); 1536 err = ext3_journal_get_write_access(handle, frame->bh); 1537 if (err) 1538 goto journal_error; 1539 if (levels) { 1540 unsigned icount1 = icount/2, icount2 = icount - icount1; 1541 unsigned hash2 = dx_get_hash(entries + icount1); 1542 dxtrace(printk("Split index %i/%i\n", icount1, icount2)); 1543 1544 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 1545 err = ext3_journal_get_write_access(handle, 1546 frames[0].bh); 1547 if (err) 1548 goto journal_error; 1549 1550 memcpy ((char *) entries2, (char *) (entries + icount1), 1551 icount2 * sizeof(struct dx_entry)); 1552 dx_set_count (entries, icount1); 1553 dx_set_count (entries2, icount2); 1554 dx_set_limit (entries2, dx_node_limit(dir)); 1555 1556 /* Which index block gets the new entry? */ 1557 if (at - entries >= icount1) { 1558 frame->at = at = at - entries - icount1 + entries2; 1559 frame->entries = entries = entries2; 1560 swap(frame->bh, bh2); 1561 } 1562 dx_insert_block (frames + 0, hash2, newblock); 1563 dxtrace(dx_show_index ("node", frames[1].entries)); 1564 dxtrace(dx_show_index ("node", 1565 ((struct dx_node *) bh2->b_data)->entries)); 1566 err = ext3_journal_dirty_metadata(handle, bh2); 1567 if (err) 1568 goto journal_error; 1569 brelse (bh2); 1570 } else { 1571 dxtrace(printk("Creating second level index...\n")); 1572 memcpy((char *) entries2, (char *) entries, 1573 icount * sizeof(struct dx_entry)); 1574 dx_set_limit(entries2, dx_node_limit(dir)); 1575 1576 /* Set up root */ 1577 dx_set_count(entries, 1); 1578 dx_set_block(entries + 0, newblock); 1579 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1; 1580 1581 /* Add new access path frame */ 1582 frame = frames + 1; 1583 frame->at = at = at - entries + entries2; 1584 frame->entries = entries = entries2; 1585 frame->bh = bh2; 1586 err = ext3_journal_get_write_access(handle, 1587 frame->bh); 1588 if (err) 1589 goto journal_error; 1590 } 1591 ext3_journal_dirty_metadata(handle, frames[0].bh); 1592 } 1593 de = do_split(handle, dir, &bh, frame, &hinfo, &err); 1594 if (!de) 1595 goto cleanup; 1596 err = add_dirent_to_buf(handle, dentry, inode, de, bh); 1597 bh = NULL; 1598 goto cleanup; 1599 1600journal_error: 1601 ext3_std_error(dir->i_sb, err); 1602cleanup: 1603 if (bh) 1604 brelse(bh); 1605 dx_release(frames); 1606 return err; 1607} 1608 1609/* 1610 * ext3_delete_entry deletes a directory entry by merging it with the 1611 * previous entry 1612 */ 1613static int ext3_delete_entry (handle_t *handle, 1614 struct inode * dir, 1615 struct ext3_dir_entry_2 * de_del, 1616 struct buffer_head * bh) 1617{ 1618 struct ext3_dir_entry_2 * de, * pde; 1619 int i; 1620 1621 i = 0; 1622 pde = NULL; 1623 de = (struct ext3_dir_entry_2 *) bh->b_data; 1624 while (i < bh->b_size) { 1625 if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i)) 1626 return -EIO; 1627 if (de == de_del) { 1628 BUFFER_TRACE(bh, "get_write_access"); 1629 ext3_journal_get_write_access(handle, bh); 1630 if (pde) 1631 pde->rec_len = ext3_rec_len_to_disk( 1632 ext3_rec_len_from_disk(pde->rec_len) + 1633 ext3_rec_len_from_disk(de->rec_len)); 1634 else 1635 de->inode = 0; 1636 dir->i_version++; 1637 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1638 ext3_journal_dirty_metadata(handle, bh); 1639 return 0; 1640 } 1641 i += ext3_rec_len_from_disk(de->rec_len); 1642 pde = de; 1643 de = ext3_next_entry(de); 1644 } 1645 return -ENOENT; 1646} 1647 1648static int ext3_add_nondir(handle_t *handle, 1649 struct dentry *dentry, struct inode *inode) 1650{ 1651 int err = ext3_add_entry(handle, dentry, inode); 1652 if (!err) { 1653 ext3_mark_inode_dirty(handle, inode); 1654 d_instantiate(dentry, inode); 1655 return 0; 1656 } 1657 drop_nlink(inode); 1658 iput(inode); 1659 return err; 1660} 1661 1662/* 1663 * By the time this is called, we already have created 1664 * the directory cache entry for the new file, but it 1665 * is so far negative - it has no inode. 1666 * 1667 * If the create succeeds, we fill in the inode information 1668 * with d_instantiate(). 1669 */ 1670static int ext3_create (struct inode * dir, struct dentry * dentry, int mode, 1671 struct nameidata *nd) 1672{ 1673 handle_t *handle; 1674 struct inode * inode; 1675 int err, retries = 0; 1676 1677retry: 1678 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1679 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1680 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1681 if (IS_ERR(handle)) 1682 return PTR_ERR(handle); 1683 1684 if (IS_DIRSYNC(dir)) 1685 handle->h_sync = 1; 1686 1687 inode = ext3_new_inode (handle, dir, mode); 1688 err = PTR_ERR(inode); 1689 if (!IS_ERR(inode)) { 1690 inode->i_op = &ext3_file_inode_operations; 1691 inode->i_fop = &ext3_file_operations; 1692 ext3_set_aops(inode); 1693 err = ext3_add_nondir(handle, dentry, inode); 1694 } 1695 ext3_journal_stop(handle); 1696 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1697 goto retry; 1698 return err; 1699} 1700 1701static int ext3_mknod (struct inode * dir, struct dentry *dentry, 1702 int mode, dev_t rdev) 1703{ 1704 handle_t *handle; 1705 struct inode *inode; 1706 int err, retries = 0; 1707 1708 if (!new_valid_dev(rdev)) 1709 return -EINVAL; 1710 1711retry: 1712 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1713 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1714 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1715 if (IS_ERR(handle)) 1716 return PTR_ERR(handle); 1717 1718 if (IS_DIRSYNC(dir)) 1719 handle->h_sync = 1; 1720 1721 inode = ext3_new_inode (handle, dir, mode); 1722 err = PTR_ERR(inode); 1723 if (!IS_ERR(inode)) { 1724 init_special_inode(inode, inode->i_mode, rdev); 1725#ifdef CONFIG_EXT3_FS_XATTR 1726 inode->i_op = &ext3_special_inode_operations; 1727#endif 1728 err = ext3_add_nondir(handle, dentry, inode); 1729 } 1730 ext3_journal_stop(handle); 1731 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1732 goto retry; 1733 return err; 1734} 1735 1736static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode) 1737{ 1738 handle_t *handle; 1739 struct inode * inode; 1740 struct buffer_head * dir_block; 1741 struct ext3_dir_entry_2 * de; 1742 int err, retries = 0; 1743 1744 if (dir->i_nlink >= EXT3_LINK_MAX) 1745 return -EMLINK; 1746 1747retry: 1748 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1749 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1750 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1751 if (IS_ERR(handle)) 1752 return PTR_ERR(handle); 1753 1754 if (IS_DIRSYNC(dir)) 1755 handle->h_sync = 1; 1756 1757 inode = ext3_new_inode (handle, dir, S_IFDIR | mode); 1758 err = PTR_ERR(inode); 1759 if (IS_ERR(inode)) 1760 goto out_stop; 1761 1762 inode->i_op = &ext3_dir_inode_operations; 1763 inode->i_fop = &ext3_dir_operations; 1764 inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize; 1765 dir_block = ext3_bread (handle, inode, 0, 1, &err); 1766 if (!dir_block) { 1767 drop_nlink(inode); /* is this nlink == 0? */ 1768 ext3_mark_inode_dirty(handle, inode); 1769 iput (inode); 1770 goto out_stop; 1771 } 1772 BUFFER_TRACE(dir_block, "get_write_access"); 1773 ext3_journal_get_write_access(handle, dir_block); 1774 de = (struct ext3_dir_entry_2 *) dir_block->b_data; 1775 de->inode = cpu_to_le32(inode->i_ino); 1776 de->name_len = 1; 1777 de->rec_len = ext3_rec_len_to_disk(EXT3_DIR_REC_LEN(de->name_len)); 1778 strcpy (de->name, "."); 1779 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1780 de = ext3_next_entry(de); 1781 de->inode = cpu_to_le32(dir->i_ino); 1782 de->rec_len = ext3_rec_len_to_disk(inode->i_sb->s_blocksize - 1783 EXT3_DIR_REC_LEN(1)); 1784 de->name_len = 2; 1785 strcpy (de->name, ".."); 1786 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1787 inode->i_nlink = 2; 1788 BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata"); 1789 ext3_journal_dirty_metadata(handle, dir_block); 1790 brelse (dir_block); 1791 ext3_mark_inode_dirty(handle, inode); 1792 err = ext3_add_entry (handle, dentry, inode); 1793 if (err) { 1794 inode->i_nlink = 0; 1795 ext3_mark_inode_dirty(handle, inode); 1796 iput (inode); 1797 goto out_stop; 1798 } 1799 inc_nlink(dir); 1800 ext3_update_dx_flag(dir); 1801 ext3_mark_inode_dirty(handle, dir); 1802 d_instantiate(dentry, inode); 1803out_stop: 1804 ext3_journal_stop(handle); 1805 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1806 goto retry; 1807 return err; 1808} 1809 1810/* 1811 * routine to check that the specified directory is empty (for rmdir) 1812 */ 1813static int empty_dir (struct inode * inode) 1814{ 1815 unsigned long offset; 1816 struct buffer_head * bh; 1817 struct ext3_dir_entry_2 * de, * de1; 1818 struct super_block * sb; 1819 int err = 0; 1820 1821 sb = inode->i_sb; 1822 if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) || 1823 !(bh = ext3_bread (NULL, inode, 0, 0, &err))) { 1824 if (err) 1825 ext3_error(inode->i_sb, __func__, 1826 "error %d reading directory #%lu offset 0", 1827 err, inode->i_ino); 1828 else 1829 ext3_warning(inode->i_sb, __func__, 1830 "bad directory (dir #%lu) - no data block", 1831 inode->i_ino); 1832 return 1; 1833 } 1834 de = (struct ext3_dir_entry_2 *) bh->b_data; 1835 de1 = ext3_next_entry(de); 1836 if (le32_to_cpu(de->inode) != inode->i_ino || 1837 !le32_to_cpu(de1->inode) || 1838 strcmp (".", de->name) || 1839 strcmp ("..", de1->name)) { 1840 ext3_warning (inode->i_sb, "empty_dir", 1841 "bad directory (dir #%lu) - no `.' or `..'", 1842 inode->i_ino); 1843 brelse (bh); 1844 return 1; 1845 } 1846 offset = ext3_rec_len_from_disk(de->rec_len) + 1847 ext3_rec_len_from_disk(de1->rec_len); 1848 de = ext3_next_entry(de1); 1849 while (offset < inode->i_size ) { 1850 if (!bh || 1851 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 1852 err = 0; 1853 brelse (bh); 1854 bh = ext3_bread (NULL, inode, 1855 offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err); 1856 if (!bh) { 1857 if (err) 1858 ext3_error(sb, __func__, 1859 "error %d reading directory" 1860 " #%lu offset %lu", 1861 err, inode->i_ino, offset); 1862 offset += sb->s_blocksize; 1863 continue; 1864 } 1865 de = (struct ext3_dir_entry_2 *) bh->b_data; 1866 } 1867 if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) { 1868 de = (struct ext3_dir_entry_2 *)(bh->b_data + 1869 sb->s_blocksize); 1870 offset = (offset | (sb->s_blocksize - 1)) + 1; 1871 continue; 1872 } 1873 if (le32_to_cpu(de->inode)) { 1874 brelse (bh); 1875 return 0; 1876 } 1877 offset += ext3_rec_len_from_disk(de->rec_len); 1878 de = ext3_next_entry(de); 1879 } 1880 brelse (bh); 1881 return 1; 1882} 1883 1884/* ext3_orphan_add() links an unlinked or truncated inode into a list of 1885 * such inodes, starting at the superblock, in case we crash before the 1886 * file is closed/deleted, or in case the inode truncate spans multiple 1887 * transactions and the last transaction is not recovered after a crash. 1888 * 1889 * At filesystem recovery time, we walk this list deleting unlinked 1890 * inodes and truncating linked inodes in ext3_orphan_cleanup(). 1891 */ 1892int ext3_orphan_add(handle_t *handle, struct inode *inode) 1893{ 1894 struct super_block *sb = inode->i_sb; 1895 struct ext3_iloc iloc; 1896 int err = 0, rc; 1897 1898 lock_super(sb); 1899 if (!list_empty(&EXT3_I(inode)->i_orphan)) 1900 goto out_unlock; 1901 1902 /* Orphan handling is only valid for files with data blocks 1903 * being truncated, or files being unlinked. */ 1904 1905 /* @@@ FIXME: Observation from aviro: 1906 * I think I can trigger J_ASSERT in ext3_orphan_add(). We block 1907 * here (on lock_super()), so race with ext3_link() which might bump 1908 * ->i_nlink. For, say it, character device. Not a regular file, 1909 * not a directory, not a symlink and ->i_nlink > 0. 1910 */ 1911 J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 1912 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 1913 1914 BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access"); 1915 err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh); 1916 if (err) 1917 goto out_unlock; 1918 1919 err = ext3_reserve_inode_write(handle, inode, &iloc); 1920 if (err) 1921 goto out_unlock; 1922 1923 /* Insert this inode at the head of the on-disk orphan list... */ 1924 NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan); 1925 EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 1926 err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh); 1927 rc = ext3_mark_iloc_dirty(handle, inode, &iloc); 1928 if (!err) 1929 err = rc; 1930 1931 /* Only add to the head of the in-memory list if all the 1932 * previous operations succeeded. If the orphan_add is going to 1933 * fail (possibly taking the journal offline), we can't risk 1934 * leaving the inode on the orphan list: stray orphan-list 1935 * entries can cause panics at unmount time. 1936 * 1937 * This is safe: on error we're going to ignore the orphan list 1938 * anyway on the next recovery. */ 1939 if (!err) 1940 list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan); 1941 1942 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 1943 jbd_debug(4, "orphan inode %lu will point to %d\n", 1944 inode->i_ino, NEXT_ORPHAN(inode)); 1945out_unlock: 1946 unlock_super(sb); 1947 ext3_std_error(inode->i_sb, err); 1948 return err; 1949} 1950 1951/* 1952 * ext3_orphan_del() removes an unlinked or truncated inode from the list 1953 * of such inodes stored on disk, because it is finally being cleaned up. 1954 */ 1955int ext3_orphan_del(handle_t *handle, struct inode *inode) 1956{ 1957 struct list_head *prev; 1958 struct ext3_inode_info *ei = EXT3_I(inode); 1959 struct ext3_sb_info *sbi; 1960 unsigned long ino_next; 1961 struct ext3_iloc iloc; 1962 int err = 0; 1963 1964 lock_super(inode->i_sb); 1965 if (list_empty(&ei->i_orphan)) { 1966 unlock_super(inode->i_sb); 1967 return 0; 1968 } 1969 1970 ino_next = NEXT_ORPHAN(inode); 1971 prev = ei->i_orphan.prev; 1972 sbi = EXT3_SB(inode->i_sb); 1973 1974 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 1975 1976 list_del_init(&ei->i_orphan); 1977 1978 /* If we're on an error path, we may not have a valid 1979 * transaction handle with which to update the orphan list on 1980 * disk, but we still need to remove the inode from the linked 1981 * list in memory. */ 1982 if (!handle) 1983 goto out; 1984 1985 err = ext3_reserve_inode_write(handle, inode, &iloc); 1986 if (err) 1987 goto out_err; 1988 1989 if (prev == &sbi->s_orphan) { 1990 jbd_debug(4, "superblock will point to %lu\n", ino_next); 1991 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 1992 err = ext3_journal_get_write_access(handle, sbi->s_sbh); 1993 if (err) 1994 goto out_brelse; 1995 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 1996 err = ext3_journal_dirty_metadata(handle, sbi->s_sbh); 1997 } else { 1998 struct ext3_iloc iloc2; 1999 struct inode *i_prev = 2000 &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode; 2001 2002 jbd_debug(4, "orphan inode %lu will point to %lu\n", 2003 i_prev->i_ino, ino_next); 2004 err = ext3_reserve_inode_write(handle, i_prev, &iloc2); 2005 if (err) 2006 goto out_brelse; 2007 NEXT_ORPHAN(i_prev) = ino_next; 2008 err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2); 2009 } 2010 if (err) 2011 goto out_brelse; 2012 NEXT_ORPHAN(inode) = 0; 2013 err = ext3_mark_iloc_dirty(handle, inode, &iloc); 2014 2015out_err: 2016 ext3_std_error(inode->i_sb, err); 2017out: 2018 unlock_super(inode->i_sb); 2019 return err; 2020 2021out_brelse: 2022 brelse(iloc.bh); 2023 goto out_err; 2024} 2025 2026static int ext3_rmdir (struct inode * dir, struct dentry *dentry) 2027{ 2028 int retval; 2029 struct inode * inode; 2030 struct buffer_head * bh; 2031 struct ext3_dir_entry_2 * de; 2032 handle_t *handle; 2033 2034 /* Initialize quotas before so that eventual writes go in 2035 * separate transaction */ 2036 DQUOT_INIT(dentry->d_inode); 2037 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2038 if (IS_ERR(handle)) 2039 return PTR_ERR(handle); 2040 2041 retval = -ENOENT; 2042 bh = ext3_find_entry(dir, &dentry->d_name, &de); 2043 if (!bh) 2044 goto end_rmdir; 2045 2046 if (IS_DIRSYNC(dir)) 2047 handle->h_sync = 1; 2048 2049 inode = dentry->d_inode; 2050 2051 retval = -EIO; 2052 if (le32_to_cpu(de->inode) != inode->i_ino) 2053 goto end_rmdir; 2054 2055 retval = -ENOTEMPTY; 2056 if (!empty_dir (inode)) 2057 goto end_rmdir; 2058 2059 retval = ext3_delete_entry(handle, dir, de, bh); 2060 if (retval) 2061 goto end_rmdir; 2062 if (inode->i_nlink != 2) 2063 ext3_warning (inode->i_sb, "ext3_rmdir", 2064 "empty directory has nlink!=2 (%d)", 2065 inode->i_nlink); 2066 inode->i_version++; 2067 clear_nlink(inode); 2068 /* There's no need to set i_disksize: the fact that i_nlink is 2069 * zero will ensure that the right thing happens during any 2070 * recovery. */ 2071 inode->i_size = 0; 2072 ext3_orphan_add(handle, inode); 2073 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2074 ext3_mark_inode_dirty(handle, inode); 2075 drop_nlink(dir); 2076 ext3_update_dx_flag(dir); 2077 ext3_mark_inode_dirty(handle, dir); 2078 2079end_rmdir: 2080 ext3_journal_stop(handle); 2081 brelse (bh); 2082 return retval; 2083} 2084 2085static int ext3_unlink(struct inode * dir, struct dentry *dentry) 2086{ 2087 int retval; 2088 struct inode * inode; 2089 struct buffer_head * bh; 2090 struct ext3_dir_entry_2 * de; 2091 handle_t *handle; 2092 2093 /* Initialize quotas before so that eventual writes go 2094 * in separate transaction */ 2095 DQUOT_INIT(dentry->d_inode); 2096 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2097 if (IS_ERR(handle)) 2098 return PTR_ERR(handle); 2099 2100 if (IS_DIRSYNC(dir)) 2101 handle->h_sync = 1; 2102 2103 retval = -ENOENT; 2104 bh = ext3_find_entry(dir, &dentry->d_name, &de); 2105 if (!bh) 2106 goto end_unlink; 2107 2108 inode = dentry->d_inode; 2109 2110 retval = -EIO; 2111 if (le32_to_cpu(de->inode) != inode->i_ino) 2112 goto end_unlink; 2113 2114 if (!inode->i_nlink) { 2115 ext3_warning (inode->i_sb, "ext3_unlink", 2116 "Deleting nonexistent file (%lu), %d", 2117 inode->i_ino, inode->i_nlink); 2118 inode->i_nlink = 1; 2119 } 2120 retval = ext3_delete_entry(handle, dir, de, bh); 2121 if (retval) 2122 goto end_unlink; 2123 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2124 ext3_update_dx_flag(dir); 2125 ext3_mark_inode_dirty(handle, dir); 2126 drop_nlink(inode); 2127 if (!inode->i_nlink) 2128 ext3_orphan_add(handle, inode); 2129 inode->i_ctime = dir->i_ctime; 2130 ext3_mark_inode_dirty(handle, inode); 2131 retval = 0; 2132 2133end_unlink: 2134 ext3_journal_stop(handle); 2135 brelse (bh); 2136 return retval; 2137} 2138 2139static int ext3_symlink (struct inode * dir, 2140 struct dentry *dentry, const char * symname) 2141{ 2142 handle_t *handle; 2143 struct inode * inode; 2144 int l, err, retries = 0; 2145 2146 l = strlen(symname)+1; 2147 if (l > dir->i_sb->s_blocksize) 2148 return -ENAMETOOLONG; 2149 2150retry: 2151 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2152 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 5 + 2153 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 2154 if (IS_ERR(handle)) 2155 return PTR_ERR(handle); 2156 2157 if (IS_DIRSYNC(dir)) 2158 handle->h_sync = 1; 2159 2160 inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO); 2161 err = PTR_ERR(inode); 2162 if (IS_ERR(inode)) 2163 goto out_stop; 2164 2165 if (l > sizeof (EXT3_I(inode)->i_data)) { 2166 inode->i_op = &ext3_symlink_inode_operations; 2167 ext3_set_aops(inode); 2168 /* 2169 * page_symlink() calls into ext3_prepare/commit_write. 2170 * We have a transaction open. All is sweetness. It also sets 2171 * i_size in generic_commit_write(). 2172 */ 2173 err = __page_symlink(inode, symname, l, 2174 mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS); 2175 if (err) { 2176 drop_nlink(inode); 2177 ext3_mark_inode_dirty(handle, inode); 2178 iput (inode); 2179 goto out_stop; 2180 } 2181 } else { 2182 inode->i_op = &ext3_fast_symlink_inode_operations; 2183 memcpy((char*)&EXT3_I(inode)->i_data,symname,l); 2184 inode->i_size = l-1; 2185 } 2186 EXT3_I(inode)->i_disksize = inode->i_size; 2187 err = ext3_add_nondir(handle, dentry, inode); 2188out_stop: 2189 ext3_journal_stop(handle); 2190 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2191 goto retry; 2192 return err; 2193} 2194 2195static int ext3_link (struct dentry * old_dentry, 2196 struct inode * dir, struct dentry *dentry) 2197{ 2198 handle_t *handle; 2199 struct inode *inode = old_dentry->d_inode; 2200 int err, retries = 0; 2201 2202 if (inode->i_nlink >= EXT3_LINK_MAX) 2203 return -EMLINK; 2204 /* 2205 * Return -ENOENT if we've raced with unlink and i_nlink is 0. Doing 2206 * otherwise has the potential to corrupt the orphan inode list. 2207 */ 2208 if (inode->i_nlink == 0) 2209 return -ENOENT; 2210 2211retry: 2212 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2213 EXT3_INDEX_EXTRA_TRANS_BLOCKS); 2214 if (IS_ERR(handle)) 2215 return PTR_ERR(handle); 2216 2217 if (IS_DIRSYNC(dir)) 2218 handle->h_sync = 1; 2219 2220 inode->i_ctime = CURRENT_TIME_SEC; 2221 inc_nlink(inode); 2222 atomic_inc(&inode->i_count); 2223 2224 err = ext3_add_nondir(handle, dentry, inode); 2225 ext3_journal_stop(handle); 2226 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2227 goto retry; 2228 return err; 2229} 2230 2231#define PARENT_INO(buffer) \ 2232 (ext3_next_entry((struct ext3_dir_entry_2 *)(buffer))->inode) 2233 2234/* 2235 * Anybody can rename anything with this: the permission checks are left to the 2236 * higher-level routines. 2237 */ 2238static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, 2239 struct inode * new_dir,struct dentry *new_dentry) 2240{ 2241 handle_t *handle; 2242 struct inode * old_inode, * new_inode; 2243 struct buffer_head * old_bh, * new_bh, * dir_bh; 2244 struct ext3_dir_entry_2 * old_de, * new_de; 2245 int retval; 2246 2247 old_bh = new_bh = dir_bh = NULL; 2248 2249 /* Initialize quotas before so that eventual writes go 2250 * in separate transaction */ 2251 if (new_dentry->d_inode) 2252 DQUOT_INIT(new_dentry->d_inode); 2253 handle = ext3_journal_start(old_dir, 2 * 2254 EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) + 2255 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2); 2256 if (IS_ERR(handle)) 2257 return PTR_ERR(handle); 2258 2259 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) 2260 handle->h_sync = 1; 2261 2262 old_bh = ext3_find_entry(old_dir, &old_dentry->d_name, &old_de); 2263 /* 2264 * Check for inode number is _not_ due to possible IO errors. 2265 * We might rmdir the source, keep it as pwd of some process 2266 * and merrily kill the link to whatever was created under the 2267 * same name. Goodbye sticky bit ;-< 2268 */ 2269 old_inode = old_dentry->d_inode; 2270 retval = -ENOENT; 2271 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino) 2272 goto end_rename; 2273 2274 new_inode = new_dentry->d_inode; 2275 new_bh = ext3_find_entry(new_dir, &new_dentry->d_name, &new_de); 2276 if (new_bh) { 2277 if (!new_inode) { 2278 brelse (new_bh); 2279 new_bh = NULL; 2280 } 2281 } 2282 if (S_ISDIR(old_inode->i_mode)) { 2283 if (new_inode) { 2284 retval = -ENOTEMPTY; 2285 if (!empty_dir (new_inode)) 2286 goto end_rename; 2287 } 2288 retval = -EIO; 2289 dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval); 2290 if (!dir_bh) 2291 goto end_rename; 2292 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino) 2293 goto end_rename; 2294 retval = -EMLINK; 2295 if (!new_inode && new_dir!=old_dir && 2296 new_dir->i_nlink >= EXT3_LINK_MAX) 2297 goto end_rename; 2298 } 2299 if (!new_bh) { 2300 retval = ext3_add_entry (handle, new_dentry, old_inode); 2301 if (retval) 2302 goto end_rename; 2303 } else { 2304 BUFFER_TRACE(new_bh, "get write access"); 2305 ext3_journal_get_write_access(handle, new_bh); 2306 new_de->inode = cpu_to_le32(old_inode->i_ino); 2307 if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb, 2308 EXT3_FEATURE_INCOMPAT_FILETYPE)) 2309 new_de->file_type = old_de->file_type; 2310 new_dir->i_version++; 2311 new_dir->i_ctime = new_dir->i_mtime = CURRENT_TIME_SEC; 2312 ext3_mark_inode_dirty(handle, new_dir); 2313 BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata"); 2314 ext3_journal_dirty_metadata(handle, new_bh); 2315 brelse(new_bh); 2316 new_bh = NULL; 2317 } 2318 2319 /* 2320 * Like most other Unix systems, set the ctime for inodes on a 2321 * rename. 2322 */ 2323 old_inode->i_ctime = CURRENT_TIME_SEC; 2324 ext3_mark_inode_dirty(handle, old_inode); 2325 2326 /* 2327 * ok, that's it 2328 */ 2329 if (le32_to_cpu(old_de->inode) != old_inode->i_ino || 2330 old_de->name_len != old_dentry->d_name.len || 2331 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) || 2332 (retval = ext3_delete_entry(handle, old_dir, 2333 old_de, old_bh)) == -ENOENT) { 2334 /* old_de could have moved from under us during htree split, so 2335 * make sure that we are deleting the right entry. We might 2336 * also be pointing to a stale entry in the unused part of 2337 * old_bh so just checking inum and the name isn't enough. */ 2338 struct buffer_head *old_bh2; 2339 struct ext3_dir_entry_2 *old_de2; 2340 2341 old_bh2 = ext3_find_entry(old_dir, &old_dentry->d_name, 2342 &old_de2); 2343 if (old_bh2) { 2344 retval = ext3_delete_entry(handle, old_dir, 2345 old_de2, old_bh2); 2346 brelse(old_bh2); 2347 } 2348 } 2349 if (retval) { 2350 ext3_warning(old_dir->i_sb, "ext3_rename", 2351 "Deleting old file (%lu), %d, error=%d", 2352 old_dir->i_ino, old_dir->i_nlink, retval); 2353 } 2354 2355 if (new_inode) { 2356 drop_nlink(new_inode); 2357 new_inode->i_ctime = CURRENT_TIME_SEC; 2358 } 2359 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; 2360 ext3_update_dx_flag(old_dir); 2361 if (dir_bh) { 2362 BUFFER_TRACE(dir_bh, "get_write_access"); 2363 ext3_journal_get_write_access(handle, dir_bh); 2364 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino); 2365 BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata"); 2366 ext3_journal_dirty_metadata(handle, dir_bh); 2367 drop_nlink(old_dir); 2368 if (new_inode) { 2369 drop_nlink(new_inode); 2370 } else { 2371 inc_nlink(new_dir); 2372 ext3_update_dx_flag(new_dir); 2373 ext3_mark_inode_dirty(handle, new_dir); 2374 } 2375 } 2376 ext3_mark_inode_dirty(handle, old_dir); 2377 if (new_inode) { 2378 ext3_mark_inode_dirty(handle, new_inode); 2379 if (!new_inode->i_nlink) 2380 ext3_orphan_add(handle, new_inode); 2381 } 2382 retval = 0; 2383 2384end_rename: 2385 brelse (dir_bh); 2386 brelse (old_bh); 2387 brelse (new_bh); 2388 ext3_journal_stop(handle); 2389 return retval; 2390} 2391 2392/* 2393 * directories can handle most operations... 2394 */ 2395const struct inode_operations ext3_dir_inode_operations = { 2396 .create = ext3_create, 2397 .lookup = ext3_lookup, 2398 .link = ext3_link, 2399 .unlink = ext3_unlink, 2400 .symlink = ext3_symlink, 2401 .mkdir = ext3_mkdir, 2402 .rmdir = ext3_rmdir, 2403 .mknod = ext3_mknod, 2404 .rename = ext3_rename, 2405 .setattr = ext3_setattr, 2406#ifdef CONFIG_EXT3_FS_XATTR 2407 .setxattr = generic_setxattr, 2408 .getxattr = generic_getxattr, 2409 .listxattr = ext3_listxattr, 2410 .removexattr = generic_removexattr, 2411#endif 2412 .permission = ext3_permission, 2413}; 2414 2415const struct inode_operations ext3_special_inode_operations = { 2416 .setattr = ext3_setattr, 2417#ifdef CONFIG_EXT3_FS_XATTR 2418 .setxattr = generic_setxattr, 2419 .getxattr = generic_getxattr, 2420 .listxattr = ext3_listxattr, 2421 .removexattr = generic_removexattr, 2422#endif 2423 .permission = ext3_permission, 2424}; 2425