namei.c revision 7c06a8dc64a2d1884bd19b4c6353d9267ae4e3e1
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 if ((bh = ext3_bread(handle, inode, *block, 1, err))) { 61 inode->i_size += inode->i_sb->s_blocksize; 62 EXT3_I(inode)->i_disksize = inode->i_size; 63 ext3_journal_get_write_access(handle,bh); 64 } 65 return bh; 66} 67 68#ifndef assert 69#define assert(test) J_ASSERT(test) 70#endif 71 72#ifndef swap 73#define swap(x, y) do { typeof(x) z = x; x = y; y = z; } while (0) 74#endif 75 76#ifdef DX_DEBUG 77#define dxtrace(command) command 78#else 79#define dxtrace(command) 80#endif 81 82struct fake_dirent 83{ 84 __le32 inode; 85 __le16 rec_len; 86 u8 name_len; 87 u8 file_type; 88}; 89 90struct dx_countlimit 91{ 92 __le16 limit; 93 __le16 count; 94}; 95 96struct dx_entry 97{ 98 __le32 hash; 99 __le32 block; 100}; 101 102/* 103 * dx_root_info is laid out so that if it should somehow get overlaid by a 104 * dirent the two low bits of the hash version will be zero. Therefore, the 105 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 106 */ 107 108struct dx_root 109{ 110 struct fake_dirent dot; 111 char dot_name[4]; 112 struct fake_dirent dotdot; 113 char dotdot_name[4]; 114 struct dx_root_info 115 { 116 __le32 reserved_zero; 117 u8 hash_version; 118 u8 info_length; /* 8 */ 119 u8 indirect_levels; 120 u8 unused_flags; 121 } 122 info; 123 struct dx_entry entries[0]; 124}; 125 126struct dx_node 127{ 128 struct fake_dirent fake; 129 struct dx_entry entries[0]; 130}; 131 132 133struct dx_frame 134{ 135 struct buffer_head *bh; 136 struct dx_entry *entries; 137 struct dx_entry *at; 138}; 139 140struct dx_map_entry 141{ 142 u32 hash; 143 u16 offs; 144 u16 size; 145}; 146 147static inline unsigned dx_get_block (struct dx_entry *entry); 148static void dx_set_block (struct dx_entry *entry, unsigned value); 149static inline unsigned dx_get_hash (struct dx_entry *entry); 150static void dx_set_hash (struct dx_entry *entry, unsigned value); 151static unsigned dx_get_count (struct dx_entry *entries); 152static unsigned dx_get_limit (struct dx_entry *entries); 153static void dx_set_count (struct dx_entry *entries, unsigned value); 154static void dx_set_limit (struct dx_entry *entries, unsigned value); 155static unsigned dx_root_limit (struct inode *dir, unsigned infosize); 156static unsigned dx_node_limit (struct inode *dir); 157static struct dx_frame *dx_probe(struct dentry *dentry, 158 struct inode *dir, 159 struct dx_hash_info *hinfo, 160 struct dx_frame *frame, 161 int *err); 162static void dx_release (struct dx_frame *frames); 163static int dx_make_map (struct ext3_dir_entry_2 *de, int size, 164 struct dx_hash_info *hinfo, struct dx_map_entry map[]); 165static void dx_sort_map(struct dx_map_entry *map, unsigned count); 166static struct ext3_dir_entry_2 *dx_move_dirents (char *from, char *to, 167 struct dx_map_entry *offsets, int count); 168static struct ext3_dir_entry_2* dx_pack_dirents (char *base, int size); 169static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block); 170static int ext3_htree_next_block(struct inode *dir, __u32 hash, 171 struct dx_frame *frame, 172 struct dx_frame *frames, 173 __u32 *start_hash); 174static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry, 175 struct ext3_dir_entry_2 **res_dir, int *err); 176static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, 177 struct inode *inode); 178 179/* 180 * p is at least 6 bytes before the end of page 181 */ 182static inline struct ext3_dir_entry_2 * 183ext3_next_entry(struct ext3_dir_entry_2 *p) 184{ 185 return (struct ext3_dir_entry_2 *)((char *)p + 186 ext3_rec_len_from_disk(p->rec_len)); 187} 188 189/* 190 * Future: use high four bits of block for coalesce-on-delete flags 191 * Mask them off for now. 192 */ 193 194static inline unsigned dx_get_block (struct dx_entry *entry) 195{ 196 return le32_to_cpu(entry->block) & 0x00ffffff; 197} 198 199static inline void dx_set_block (struct dx_entry *entry, unsigned value) 200{ 201 entry->block = cpu_to_le32(value); 202} 203 204static inline unsigned dx_get_hash (struct dx_entry *entry) 205{ 206 return le32_to_cpu(entry->hash); 207} 208 209static inline void dx_set_hash (struct dx_entry *entry, unsigned value) 210{ 211 entry->hash = cpu_to_le32(value); 212} 213 214static inline unsigned dx_get_count (struct dx_entry *entries) 215{ 216 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 217} 218 219static inline unsigned dx_get_limit (struct dx_entry *entries) 220{ 221 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 222} 223 224static inline void dx_set_count (struct dx_entry *entries, unsigned value) 225{ 226 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 227} 228 229static inline void dx_set_limit (struct dx_entry *entries, unsigned value) 230{ 231 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 232} 233 234static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize) 235{ 236 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) - 237 EXT3_DIR_REC_LEN(2) - infosize; 238 return 0? 20: entry_space / sizeof(struct dx_entry); 239} 240 241static inline unsigned dx_node_limit (struct inode *dir) 242{ 243 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0); 244 return 0? 22: entry_space / sizeof(struct dx_entry); 245} 246 247/* 248 * Debug 249 */ 250#ifdef DX_DEBUG 251static void dx_show_index (char * label, struct dx_entry *entries) 252{ 253 int i, n = dx_get_count (entries); 254 printk("%s index ", label); 255 for (i = 0; i < n; i++) 256 { 257 printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i)); 258 } 259 printk("\n"); 260} 261 262struct stats 263{ 264 unsigned names; 265 unsigned space; 266 unsigned bcount; 267}; 268 269static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de, 270 int size, int show_names) 271{ 272 unsigned names = 0, space = 0; 273 char *base = (char *) de; 274 struct dx_hash_info h = *hinfo; 275 276 printk("names: "); 277 while ((char *) de < base + size) 278 { 279 if (de->inode) 280 { 281 if (show_names) 282 { 283 int len = de->name_len; 284 char *name = de->name; 285 while (len--) printk("%c", *name++); 286 ext3fs_dirhash(de->name, de->name_len, &h); 287 printk(":%x.%u ", h.hash, 288 ((char *) de - base)); 289 } 290 space += EXT3_DIR_REC_LEN(de->name_len); 291 names++; 292 } 293 de = ext3_next_entry(de); 294 } 295 printk("(%i)\n", names); 296 return (struct stats) { names, space, 1 }; 297} 298 299struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 300 struct dx_entry *entries, int levels) 301{ 302 unsigned blocksize = dir->i_sb->s_blocksize; 303 unsigned count = dx_get_count (entries), names = 0, space = 0, i; 304 unsigned bcount = 0; 305 struct buffer_head *bh; 306 int err; 307 printk("%i indexed blocks...\n", count); 308 for (i = 0; i < count; i++, entries++) 309 { 310 u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0; 311 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 312 struct stats stats; 313 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 314 if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue; 315 stats = levels? 316 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 317 dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0); 318 names += stats.names; 319 space += stats.space; 320 bcount += stats.bcount; 321 brelse (bh); 322 } 323 if (bcount) 324 printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ", 325 names, space/bcount,(space/bcount)*100/blocksize); 326 return (struct stats) { names, space, bcount}; 327} 328#endif /* DX_DEBUG */ 329 330/* 331 * Probe for a directory leaf block to search. 332 * 333 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 334 * error in the directory index, and the caller should fall back to 335 * searching the directory normally. The callers of dx_probe **MUST** 336 * check for this error code, and make sure it never gets reflected 337 * back to userspace. 338 */ 339static struct dx_frame * 340dx_probe(struct dentry *dentry, struct inode *dir, 341 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err) 342{ 343 unsigned count, indirect; 344 struct dx_entry *at, *entries, *p, *q, *m; 345 struct dx_root *root; 346 struct buffer_head *bh; 347 struct dx_frame *frame = frame_in; 348 u32 hash; 349 350 frame->bh = NULL; 351 if (dentry) 352 dir = dentry->d_parent->d_inode; 353 if (!(bh = ext3_bread (NULL,dir, 0, 0, err))) 354 goto fail; 355 root = (struct dx_root *) bh->b_data; 356 if (root->info.hash_version != DX_HASH_TEA && 357 root->info.hash_version != DX_HASH_HALF_MD4 && 358 root->info.hash_version != DX_HASH_LEGACY) { 359 ext3_warning(dir->i_sb, __FUNCTION__, 360 "Unrecognised inode hash code %d", 361 root->info.hash_version); 362 brelse(bh); 363 *err = ERR_BAD_DX_DIR; 364 goto fail; 365 } 366 hinfo->hash_version = root->info.hash_version; 367 hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed; 368 if (dentry) 369 ext3fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo); 370 hash = hinfo->hash; 371 372 if (root->info.unused_flags & 1) { 373 ext3_warning(dir->i_sb, __FUNCTION__, 374 "Unimplemented inode hash flags: %#06x", 375 root->info.unused_flags); 376 brelse(bh); 377 *err = ERR_BAD_DX_DIR; 378 goto fail; 379 } 380 381 if ((indirect = root->info.indirect_levels) > 1) { 382 ext3_warning(dir->i_sb, __FUNCTION__, 383 "Unimplemented inode hash depth: %#06x", 384 root->info.indirect_levels); 385 brelse(bh); 386 *err = ERR_BAD_DX_DIR; 387 goto fail; 388 } 389 390 entries = (struct dx_entry *) (((char *)&root->info) + 391 root->info.info_length); 392 393 if (dx_get_limit(entries) != dx_root_limit(dir, 394 root->info.info_length)) { 395 ext3_warning(dir->i_sb, __FUNCTION__, 396 "dx entry: limit != root limit"); 397 brelse(bh); 398 *err = ERR_BAD_DX_DIR; 399 goto fail; 400 } 401 402 dxtrace (printk("Look up %x", hash)); 403 while (1) 404 { 405 count = dx_get_count(entries); 406 if (!count || count > dx_get_limit(entries)) { 407 ext3_warning(dir->i_sb, __FUNCTION__, 408 "dx entry: no count or count > limit"); 409 brelse(bh); 410 *err = ERR_BAD_DX_DIR; 411 goto fail2; 412 } 413 414 p = entries + 1; 415 q = entries + count - 1; 416 while (p <= q) 417 { 418 m = p + (q - p)/2; 419 dxtrace(printk(".")); 420 if (dx_get_hash(m) > hash) 421 q = m - 1; 422 else 423 p = m + 1; 424 } 425 426 if (0) // linear search cross check 427 { 428 unsigned n = count - 1; 429 at = entries; 430 while (n--) 431 { 432 dxtrace(printk(",")); 433 if (dx_get_hash(++at) > hash) 434 { 435 at--; 436 break; 437 } 438 } 439 assert (at == p - 1); 440 } 441 442 at = p - 1; 443 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at))); 444 frame->bh = bh; 445 frame->entries = entries; 446 frame->at = at; 447 if (!indirect--) return frame; 448 if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err))) 449 goto fail2; 450 at = entries = ((struct dx_node *) bh->b_data)->entries; 451 if (dx_get_limit(entries) != dx_node_limit (dir)) { 452 ext3_warning(dir->i_sb, __FUNCTION__, 453 "dx entry: limit != node limit"); 454 brelse(bh); 455 *err = ERR_BAD_DX_DIR; 456 goto fail2; 457 } 458 frame++; 459 frame->bh = NULL; 460 } 461fail2: 462 while (frame >= frame_in) { 463 brelse(frame->bh); 464 frame--; 465 } 466fail: 467 if (*err == ERR_BAD_DX_DIR) 468 ext3_warning(dir->i_sb, __FUNCTION__, 469 "Corrupt dir inode %ld, running e2fsck is " 470 "recommended.", dir->i_ino); 471 return NULL; 472} 473 474static void dx_release (struct dx_frame *frames) 475{ 476 if (frames[0].bh == NULL) 477 return; 478 479 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels) 480 brelse(frames[1].bh); 481 brelse(frames[0].bh); 482} 483 484/* 485 * This function increments the frame pointer to search the next leaf 486 * block, and reads in the necessary intervening nodes if the search 487 * should be necessary. Whether or not the search is necessary is 488 * controlled by the hash parameter. If the hash value is even, then 489 * the search is only continued if the next block starts with that 490 * hash value. This is used if we are searching for a specific file. 491 * 492 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 493 * 494 * This function returns 1 if the caller should continue to search, 495 * or 0 if it should not. If there is an error reading one of the 496 * index blocks, it will a negative error code. 497 * 498 * If start_hash is non-null, it will be filled in with the starting 499 * hash of the next page. 500 */ 501static int ext3_htree_next_block(struct inode *dir, __u32 hash, 502 struct dx_frame *frame, 503 struct dx_frame *frames, 504 __u32 *start_hash) 505{ 506 struct dx_frame *p; 507 struct buffer_head *bh; 508 int err, num_frames = 0; 509 __u32 bhash; 510 511 p = frame; 512 /* 513 * Find the next leaf page by incrementing the frame pointer. 514 * If we run out of entries in the interior node, loop around and 515 * increment pointer in the parent node. When we break out of 516 * this loop, num_frames indicates the number of interior 517 * nodes need to be read. 518 */ 519 while (1) { 520 if (++(p->at) < p->entries + dx_get_count(p->entries)) 521 break; 522 if (p == frames) 523 return 0; 524 num_frames++; 525 p--; 526 } 527 528 /* 529 * If the hash is 1, then continue only if the next page has a 530 * continuation hash of any value. This is used for readdir 531 * handling. Otherwise, check to see if the hash matches the 532 * desired contiuation hash. If it doesn't, return since 533 * there's no point to read in the successive index pages. 534 */ 535 bhash = dx_get_hash(p->at); 536 if (start_hash) 537 *start_hash = bhash; 538 if ((hash & 1) == 0) { 539 if ((bhash & ~1) != hash) 540 return 0; 541 } 542 /* 543 * If the hash is HASH_NB_ALWAYS, we always go to the next 544 * block so no check is necessary 545 */ 546 while (num_frames--) { 547 if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at), 548 0, &err))) 549 return err; /* Failure */ 550 p++; 551 brelse (p->bh); 552 p->bh = bh; 553 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 554 } 555 return 1; 556} 557 558 559/* 560 * This function fills a red-black tree with information from a 561 * directory block. It returns the number directory entries loaded 562 * into the tree. If there is an error it is returned in err. 563 */ 564static int htree_dirblock_to_tree(struct file *dir_file, 565 struct inode *dir, int block, 566 struct dx_hash_info *hinfo, 567 __u32 start_hash, __u32 start_minor_hash) 568{ 569 struct buffer_head *bh; 570 struct ext3_dir_entry_2 *de, *top; 571 int err, count = 0; 572 573 dxtrace(printk("In htree dirblock_to_tree: block %d\n", block)); 574 if (!(bh = ext3_bread (NULL, dir, block, 0, &err))) 575 return err; 576 577 de = (struct ext3_dir_entry_2 *) bh->b_data; 578 top = (struct ext3_dir_entry_2 *) ((char *) de + 579 dir->i_sb->s_blocksize - 580 EXT3_DIR_REC_LEN(0)); 581 for (; de < top; de = ext3_next_entry(de)) { 582 if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh, 583 (block<<EXT3_BLOCK_SIZE_BITS(dir->i_sb)) 584 +((char *)de - bh->b_data))) { 585 /* On error, skip the f_pos to the next block. */ 586 dir_file->f_pos = (dir_file->f_pos | 587 (dir->i_sb->s_blocksize - 1)) + 1; 588 brelse (bh); 589 return count; 590 } 591 ext3fs_dirhash(de->name, de->name_len, hinfo); 592 if ((hinfo->hash < start_hash) || 593 ((hinfo->hash == start_hash) && 594 (hinfo->minor_hash < start_minor_hash))) 595 continue; 596 if (de->inode == 0) 597 continue; 598 if ((err = ext3_htree_store_dirent(dir_file, 599 hinfo->hash, hinfo->minor_hash, de)) != 0) { 600 brelse(bh); 601 return err; 602 } 603 count++; 604 } 605 brelse(bh); 606 return count; 607} 608 609 610/* 611 * This function fills a red-black tree with information from a 612 * directory. We start scanning the directory in hash order, starting 613 * at start_hash and start_minor_hash. 614 * 615 * This function returns the number of entries inserted into the tree, 616 * or a negative error code. 617 */ 618int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash, 619 __u32 start_minor_hash, __u32 *next_hash) 620{ 621 struct dx_hash_info hinfo; 622 struct ext3_dir_entry_2 *de; 623 struct dx_frame frames[2], *frame; 624 struct inode *dir; 625 int block, err; 626 int count = 0; 627 int ret; 628 __u32 hashval; 629 630 dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash, 631 start_minor_hash)); 632 dir = dir_file->f_path.dentry->d_inode; 633 if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) { 634 hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 635 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 636 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 637 start_hash, start_minor_hash); 638 *next_hash = ~0; 639 return count; 640 } 641 hinfo.hash = start_hash; 642 hinfo.minor_hash = 0; 643 frame = dx_probe(NULL, dir_file->f_path.dentry->d_inode, &hinfo, frames, &err); 644 if (!frame) 645 return err; 646 647 /* Add '.' and '..' from the htree header */ 648 if (!start_hash && !start_minor_hash) { 649 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 650 if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0) 651 goto errout; 652 count++; 653 } 654 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 655 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 656 de = ext3_next_entry(de); 657 if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0) 658 goto errout; 659 count++; 660 } 661 662 while (1) { 663 block = dx_get_block(frame->at); 664 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 665 start_hash, start_minor_hash); 666 if (ret < 0) { 667 err = ret; 668 goto errout; 669 } 670 count += ret; 671 hashval = ~0; 672 ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS, 673 frame, frames, &hashval); 674 *next_hash = hashval; 675 if (ret < 0) { 676 err = ret; 677 goto errout; 678 } 679 /* 680 * Stop if: (a) there are no more entries, or 681 * (b) we have inserted at least one entry and the 682 * next hash value is not a continuation 683 */ 684 if ((ret == 0) || 685 (count && ((hashval & 1) == 0))) 686 break; 687 } 688 dx_release(frames); 689 dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n", 690 count, *next_hash)); 691 return count; 692errout: 693 dx_release(frames); 694 return (err); 695} 696 697 698/* 699 * Directory block splitting, compacting 700 */ 701 702/* 703 * Create map of hash values, offsets, and sizes, stored at end of block. 704 * Returns number of entries mapped. 705 */ 706static int dx_make_map (struct ext3_dir_entry_2 *de, int size, 707 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail) 708{ 709 int count = 0; 710 char *base = (char *) de; 711 struct dx_hash_info h = *hinfo; 712 713 while ((char *) de < base + size) 714 { 715 if (de->name_len && de->inode) { 716 ext3fs_dirhash(de->name, de->name_len, &h); 717 map_tail--; 718 map_tail->hash = h.hash; 719 map_tail->offs = (u16) ((char *) de - base); 720 map_tail->size = le16_to_cpu(de->rec_len); 721 count++; 722 cond_resched(); 723 } 724 /* XXX: do we need to check rec_len == 0 case? -Chris */ 725 de = ext3_next_entry(de); 726 } 727 return count; 728} 729 730/* Sort map by hash value */ 731static void dx_sort_map (struct dx_map_entry *map, unsigned count) 732{ 733 struct dx_map_entry *p, *q, *top = map + count - 1; 734 int more; 735 /* Combsort until bubble sort doesn't suck */ 736 while (count > 2) 737 { 738 count = count*10/13; 739 if (count - 9 < 2) /* 9, 10 -> 11 */ 740 count = 11; 741 for (p = top, q = p - count; q >= map; p--, q--) 742 if (p->hash < q->hash) 743 swap(*p, *q); 744 } 745 /* Garden variety bubble sort */ 746 do { 747 more = 0; 748 q = top; 749 while (q-- > map) 750 { 751 if (q[1].hash >= q[0].hash) 752 continue; 753 swap(*(q+1), *q); 754 more = 1; 755 } 756 } while(more); 757} 758 759static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block) 760{ 761 struct dx_entry *entries = frame->entries; 762 struct dx_entry *old = frame->at, *new = old + 1; 763 int count = dx_get_count(entries); 764 765 assert(count < dx_get_limit(entries)); 766 assert(old < entries + count); 767 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 768 dx_set_hash(new, hash); 769 dx_set_block(new, block); 770 dx_set_count(entries, count + 1); 771} 772 773static void ext3_update_dx_flag(struct inode *inode) 774{ 775 if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb, 776 EXT3_FEATURE_COMPAT_DIR_INDEX)) 777 EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL; 778} 779 780/* 781 * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure. 782 * 783 * `len <= EXT3_NAME_LEN' is guaranteed by caller. 784 * `de != NULL' is guaranteed by caller. 785 */ 786static inline int ext3_match (int len, const char * const name, 787 struct ext3_dir_entry_2 * de) 788{ 789 if (len != de->name_len) 790 return 0; 791 if (!de->inode) 792 return 0; 793 return !memcmp(name, de->name, len); 794} 795 796/* 797 * Returns 0 if not found, -1 on failure, and 1 on success 798 */ 799static inline int search_dirblock(struct buffer_head * bh, 800 struct inode *dir, 801 struct dentry *dentry, 802 unsigned long offset, 803 struct ext3_dir_entry_2 ** res_dir) 804{ 805 struct ext3_dir_entry_2 * de; 806 char * dlimit; 807 int de_len; 808 const char *name = dentry->d_name.name; 809 int namelen = dentry->d_name.len; 810 811 de = (struct ext3_dir_entry_2 *) bh->b_data; 812 dlimit = bh->b_data + dir->i_sb->s_blocksize; 813 while ((char *) de < dlimit) { 814 /* this code is executed quadratically often */ 815 /* do minimal checking `by hand' */ 816 817 if ((char *) de + namelen <= dlimit && 818 ext3_match (namelen, name, de)) { 819 /* found a match - just to be sure, do a full check */ 820 if (!ext3_check_dir_entry("ext3_find_entry", 821 dir, de, bh, offset)) 822 return -1; 823 *res_dir = de; 824 return 1; 825 } 826 /* prevent looping on a bad block */ 827 de_len = ext3_rec_len_from_disk(de->rec_len); 828 if (de_len <= 0) 829 return -1; 830 offset += de_len; 831 de = (struct ext3_dir_entry_2 *) ((char *) de + de_len); 832 } 833 return 0; 834} 835 836 837/* 838 * ext3_find_entry() 839 * 840 * finds an entry in the specified directory with the wanted name. It 841 * returns the cache buffer in which the entry was found, and the entry 842 * itself (as a parameter - res_dir). It does NOT read the inode of the 843 * entry - you'll have to do that yourself if you want to. 844 * 845 * The returned buffer_head has ->b_count elevated. The caller is expected 846 * to brelse() it when appropriate. 847 */ 848static struct buffer_head * ext3_find_entry (struct dentry *dentry, 849 struct ext3_dir_entry_2 ** res_dir) 850{ 851 struct super_block * sb; 852 struct buffer_head * bh_use[NAMEI_RA_SIZE]; 853 struct buffer_head * bh, *ret = NULL; 854 unsigned long start, block, b; 855 int ra_max = 0; /* Number of bh's in the readahead 856 buffer, bh_use[] */ 857 int ra_ptr = 0; /* Current index into readahead 858 buffer */ 859 int num = 0; 860 int nblocks, i, err; 861 struct inode *dir = dentry->d_parent->d_inode; 862 int namelen; 863 const u8 *name; 864 unsigned blocksize; 865 866 *res_dir = NULL; 867 sb = dir->i_sb; 868 blocksize = sb->s_blocksize; 869 namelen = dentry->d_name.len; 870 name = dentry->d_name.name; 871 if (namelen > EXT3_NAME_LEN) 872 return NULL; 873 if (is_dx(dir)) { 874 bh = ext3_dx_find_entry(dentry, 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, __FUNCTION__, "reading directory #%lu " 921 "offset %lu", dir->i_ino, block); 922 brelse(bh); 923 goto next; 924 } 925 i = search_dirblock(bh, dir, dentry, 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 dentry *dentry, 960 struct ext3_dir_entry_2 **res_dir, int *err) 961{ 962 struct super_block * sb; 963 struct dx_hash_info hinfo; 964 u32 hash; 965 struct dx_frame frames[2], *frame; 966 struct ext3_dir_entry_2 *de, *top; 967 struct buffer_head *bh; 968 unsigned long block; 969 int retval; 970 int namelen = dentry->d_name.len; 971 const u8 *name = dentry->d_name.name; 972 struct inode *dir = dentry->d_parent->d_inode; 973 974 sb = dir->i_sb; 975 /* NFS may look up ".." - look at dx_root directory block */ 976 if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){ 977 if (!(frame = dx_probe(dentry, NULL, &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 if (ext3_match (namelen, name, de)) { 995 if (!ext3_check_dir_entry("ext3_find_entry", 996 dir, de, bh, 997 (block<<EXT3_BLOCK_SIZE_BITS(sb)) 998 +((char *)de - bh->b_data))) { 999 brelse (bh); 1000 *err = ERR_BAD_DX_DIR; 1001 goto errout; 1002 } 1003 *res_dir = de; 1004 dx_release (frames); 1005 return bh; 1006 } 1007 brelse (bh); 1008 /* Check to see if we should continue to search */ 1009 retval = ext3_htree_next_block(dir, hash, frame, 1010 frames, NULL); 1011 if (retval < 0) { 1012 ext3_warning(sb, __FUNCTION__, 1013 "error reading index page in directory #%lu", 1014 dir->i_ino); 1015 *err = retval; 1016 goto errout; 1017 } 1018 } while (retval == 1); 1019 1020 *err = -ENOENT; 1021errout: 1022 dxtrace(printk("%s not found\n", name)); 1023 dx_release (frames); 1024 return NULL; 1025} 1026 1027static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) 1028{ 1029 struct inode * inode; 1030 struct ext3_dir_entry_2 * de; 1031 struct buffer_head * bh; 1032 1033 if (dentry->d_name.len > EXT3_NAME_LEN) 1034 return ERR_PTR(-ENAMETOOLONG); 1035 1036 bh = ext3_find_entry(dentry, &de); 1037 inode = NULL; 1038 if (bh) { 1039 unsigned long ino = le32_to_cpu(de->inode); 1040 brelse (bh); 1041 if (!ext3_valid_inum(dir->i_sb, ino)) { 1042 ext3_error(dir->i_sb, "ext3_lookup", 1043 "bad inode number: %lu", ino); 1044 inode = NULL; 1045 } else 1046 inode = iget(dir->i_sb, ino); 1047 1048 if (!inode) 1049 return ERR_PTR(-EACCES); 1050 1051 if (is_bad_inode(inode)) { 1052 iput(inode); 1053 return ERR_PTR(-ENOENT); 1054 } 1055 } 1056 return d_splice_alias(inode, dentry); 1057} 1058 1059 1060struct dentry *ext3_get_parent(struct dentry *child) 1061{ 1062 unsigned long ino; 1063 struct dentry *parent; 1064 struct inode *inode; 1065 struct dentry dotdot; 1066 struct ext3_dir_entry_2 * de; 1067 struct buffer_head *bh; 1068 1069 dotdot.d_name.name = ".."; 1070 dotdot.d_name.len = 2; 1071 dotdot.d_parent = child; /* confusing, isn't it! */ 1072 1073 bh = ext3_find_entry(&dotdot, &de); 1074 inode = NULL; 1075 if (!bh) 1076 return ERR_PTR(-ENOENT); 1077 ino = le32_to_cpu(de->inode); 1078 brelse(bh); 1079 1080 if (!ext3_valid_inum(child->d_inode->i_sb, ino)) { 1081 ext3_error(child->d_inode->i_sb, "ext3_get_parent", 1082 "bad inode number: %lu", ino); 1083 inode = NULL; 1084 } else 1085 inode = iget(child->d_inode->i_sb, ino); 1086 1087 if (!inode) 1088 return ERR_PTR(-EACCES); 1089 1090 if (is_bad_inode(inode)) { 1091 iput(inode); 1092 return ERR_PTR(-ENOENT); 1093 } 1094 1095 parent = d_alloc_anon(inode); 1096 if (!parent) { 1097 iput(inode); 1098 parent = ERR_PTR(-ENOMEM); 1099 } 1100 return parent; 1101} 1102 1103#define S_SHIFT 12 1104static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = { 1105 [S_IFREG >> S_SHIFT] = EXT3_FT_REG_FILE, 1106 [S_IFDIR >> S_SHIFT] = EXT3_FT_DIR, 1107 [S_IFCHR >> S_SHIFT] = EXT3_FT_CHRDEV, 1108 [S_IFBLK >> S_SHIFT] = EXT3_FT_BLKDEV, 1109 [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO, 1110 [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK, 1111 [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK, 1112}; 1113 1114static inline void ext3_set_de_type(struct super_block *sb, 1115 struct ext3_dir_entry_2 *de, 1116 umode_t mode) { 1117 if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE)) 1118 de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; 1119} 1120 1121/* 1122 * Move count entries from end of map between two memory locations. 1123 * Returns pointer to last entry moved. 1124 */ 1125static struct ext3_dir_entry_2 * 1126dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) 1127{ 1128 unsigned rec_len = 0; 1129 1130 while (count--) { 1131 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs); 1132 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1133 memcpy (to, de, rec_len); 1134 ((struct ext3_dir_entry_2 *) to)->rec_len = 1135 ext3_rec_len_to_disk(rec_len); 1136 de->inode = 0; 1137 map++; 1138 to += rec_len; 1139 } 1140 return (struct ext3_dir_entry_2 *) (to - rec_len); 1141} 1142 1143/* 1144 * Compact each dir entry in the range to the minimal rec_len. 1145 * Returns pointer to last entry in range. 1146 */ 1147static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size) 1148{ 1149 struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base; 1150 unsigned rec_len = 0; 1151 1152 prev = to = de; 1153 while ((char*)de < base + size) { 1154 next = ext3_next_entry(de); 1155 if (de->inode && de->name_len) { 1156 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1157 if (de > to) 1158 memmove(to, de, rec_len); 1159 to->rec_len = ext3_rec_len_to_disk(rec_len); 1160 prev = to; 1161 to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len); 1162 } 1163 de = next; 1164 } 1165 return prev; 1166} 1167 1168/* 1169 * Split a full leaf block to make room for a new dir entry. 1170 * Allocate a new block, and move entries so that they are approx. equally full. 1171 * Returns pointer to de in block into which the new entry will be inserted. 1172 */ 1173static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1174 struct buffer_head **bh,struct dx_frame *frame, 1175 struct dx_hash_info *hinfo, int *error) 1176{ 1177 unsigned blocksize = dir->i_sb->s_blocksize; 1178 unsigned count, continued; 1179 struct buffer_head *bh2; 1180 u32 newblock; 1181 u32 hash2; 1182 struct dx_map_entry *map; 1183 char *data1 = (*bh)->b_data, *data2; 1184 unsigned split, move, size, i; 1185 struct ext3_dir_entry_2 *de = NULL, *de2; 1186 int err = 0; 1187 1188 bh2 = ext3_append (handle, dir, &newblock, &err); 1189 if (!(bh2)) { 1190 brelse(*bh); 1191 *bh = NULL; 1192 goto errout; 1193 } 1194 1195 BUFFER_TRACE(*bh, "get_write_access"); 1196 err = ext3_journal_get_write_access(handle, *bh); 1197 if (err) 1198 goto journal_error; 1199 1200 BUFFER_TRACE(frame->bh, "get_write_access"); 1201 err = ext3_journal_get_write_access(handle, frame->bh); 1202 if (err) 1203 goto journal_error; 1204 1205 data2 = bh2->b_data; 1206 1207 /* create map in the end of data2 block */ 1208 map = (struct dx_map_entry *) (data2 + blocksize); 1209 count = dx_make_map ((struct ext3_dir_entry_2 *) data1, 1210 blocksize, hinfo, map); 1211 map -= count; 1212 dx_sort_map (map, count); 1213 /* Split the existing block in the middle, size-wise */ 1214 size = 0; 1215 move = 0; 1216 for (i = count-1; i >= 0; i--) { 1217 /* is more than half of this entry in 2nd half of the block? */ 1218 if (size + map[i].size/2 > blocksize/2) 1219 break; 1220 size += map[i].size; 1221 move++; 1222 } 1223 /* map index at which we will split */ 1224 split = count - move; 1225 hash2 = map[split].hash; 1226 continued = hash2 == map[split - 1].hash; 1227 dxtrace(printk("Split block %i at %x, %i/%i\n", 1228 dx_get_block(frame->at), hash2, split, count-split)); 1229 1230 /* Fancy dance to stay within two buffers */ 1231 de2 = dx_move_dirents(data1, data2, map + split, count - split); 1232 de = dx_pack_dirents(data1,blocksize); 1233 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de); 1234 de2->rec_len = ext3_rec_len_to_disk(data2 + blocksize - (char *) de2); 1235 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1)); 1236 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1)); 1237 1238 /* Which block gets the new entry? */ 1239 if (hinfo->hash >= hash2) 1240 { 1241 swap(*bh, bh2); 1242 de = de2; 1243 } 1244 dx_insert_block (frame, hash2 + continued, newblock); 1245 err = ext3_journal_dirty_metadata (handle, bh2); 1246 if (err) 1247 goto journal_error; 1248 err = ext3_journal_dirty_metadata (handle, frame->bh); 1249 if (err) 1250 goto journal_error; 1251 brelse (bh2); 1252 dxtrace(dx_show_index ("frame", frame->entries)); 1253 return de; 1254 1255journal_error: 1256 brelse(*bh); 1257 brelse(bh2); 1258 *bh = NULL; 1259 ext3_std_error(dir->i_sb, err); 1260errout: 1261 *error = err; 1262 return NULL; 1263} 1264 1265 1266/* 1267 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1268 * it points to a directory entry which is guaranteed to be large 1269 * enough for new directory entry. If de is NULL, then 1270 * add_dirent_to_buf will attempt search the directory block for 1271 * space. It will return -ENOSPC if no space is available, and -EIO 1272 * and -EEXIST if directory entry already exists. 1273 * 1274 * NOTE! bh is NOT released in the case where ENOSPC is returned. In 1275 * all other cases bh is released. 1276 */ 1277static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, 1278 struct inode *inode, struct ext3_dir_entry_2 *de, 1279 struct buffer_head * bh) 1280{ 1281 struct inode *dir = dentry->d_parent->d_inode; 1282 const char *name = dentry->d_name.name; 1283 int namelen = dentry->d_name.len; 1284 unsigned long offset = 0; 1285 unsigned short reclen; 1286 int nlen, rlen, err; 1287 char *top; 1288 1289 reclen = EXT3_DIR_REC_LEN(namelen); 1290 if (!de) { 1291 de = (struct ext3_dir_entry_2 *)bh->b_data; 1292 top = bh->b_data + dir->i_sb->s_blocksize - reclen; 1293 while ((char *) de <= top) { 1294 if (!ext3_check_dir_entry("ext3_add_entry", dir, de, 1295 bh, offset)) { 1296 brelse (bh); 1297 return -EIO; 1298 } 1299 if (ext3_match (namelen, name, de)) { 1300 brelse (bh); 1301 return -EEXIST; 1302 } 1303 nlen = EXT3_DIR_REC_LEN(de->name_len); 1304 rlen = ext3_rec_len_from_disk(de->rec_len); 1305 if ((de->inode? rlen - nlen: rlen) >= reclen) 1306 break; 1307 de = (struct ext3_dir_entry_2 *)((char *)de + rlen); 1308 offset += rlen; 1309 } 1310 if ((char *) de > top) 1311 return -ENOSPC; 1312 } 1313 BUFFER_TRACE(bh, "get_write_access"); 1314 err = ext3_journal_get_write_access(handle, bh); 1315 if (err) { 1316 ext3_std_error(dir->i_sb, err); 1317 brelse(bh); 1318 return err; 1319 } 1320 1321 /* By now the buffer is marked for journaling */ 1322 nlen = EXT3_DIR_REC_LEN(de->name_len); 1323 rlen = ext3_rec_len_from_disk(de->rec_len); 1324 if (de->inode) { 1325 struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen); 1326 de1->rec_len = ext3_rec_len_to_disk(rlen - nlen); 1327 de->rec_len = ext3_rec_len_to_disk(nlen); 1328 de = de1; 1329 } 1330 de->file_type = EXT3_FT_UNKNOWN; 1331 if (inode) { 1332 de->inode = cpu_to_le32(inode->i_ino); 1333 ext3_set_de_type(dir->i_sb, de, inode->i_mode); 1334 } else 1335 de->inode = 0; 1336 de->name_len = namelen; 1337 memcpy (de->name, name, namelen); 1338 /* 1339 * XXX shouldn't update any times until successful 1340 * completion of syscall, but too many callers depend 1341 * on this. 1342 * 1343 * XXX similarly, too many callers depend on 1344 * ext3_new_inode() setting the times, but error 1345 * recovery deletes the inode, so the worst that can 1346 * happen is that the times are slightly out of date 1347 * and/or different from the directory change time. 1348 */ 1349 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; 1350 ext3_update_dx_flag(dir); 1351 dir->i_version++; 1352 ext3_mark_inode_dirty(handle, dir); 1353 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1354 err = ext3_journal_dirty_metadata(handle, bh); 1355 if (err) 1356 ext3_std_error(dir->i_sb, err); 1357 brelse(bh); 1358 return 0; 1359} 1360 1361/* 1362 * This converts a one block unindexed directory to a 3 block indexed 1363 * directory, and adds the dentry to the indexed directory. 1364 */ 1365static int make_indexed_dir(handle_t *handle, struct dentry *dentry, 1366 struct inode *inode, struct buffer_head *bh) 1367{ 1368 struct inode *dir = dentry->d_parent->d_inode; 1369 const char *name = dentry->d_name.name; 1370 int namelen = dentry->d_name.len; 1371 struct buffer_head *bh2; 1372 struct dx_root *root; 1373 struct dx_frame frames[2], *frame; 1374 struct dx_entry *entries; 1375 struct ext3_dir_entry_2 *de, *de2; 1376 char *data1, *top; 1377 unsigned len; 1378 int retval; 1379 unsigned blocksize; 1380 struct dx_hash_info hinfo; 1381 u32 block; 1382 struct fake_dirent *fde; 1383 1384 blocksize = dir->i_sb->s_blocksize; 1385 dxtrace(printk("Creating index\n")); 1386 retval = ext3_journal_get_write_access(handle, bh); 1387 if (retval) { 1388 ext3_std_error(dir->i_sb, retval); 1389 brelse(bh); 1390 return retval; 1391 } 1392 root = (struct dx_root *) bh->b_data; 1393 1394 bh2 = ext3_append (handle, dir, &block, &retval); 1395 if (!(bh2)) { 1396 brelse(bh); 1397 return retval; 1398 } 1399 EXT3_I(dir)->i_flags |= EXT3_INDEX_FL; 1400 data1 = bh2->b_data; 1401 1402 /* The 0th block becomes the root, move the dirents out */ 1403 fde = &root->dotdot; 1404 de = (struct ext3_dir_entry_2 *)((char *)fde + 1405 ext3_rec_len_from_disk(fde->rec_len)); 1406 len = ((char *) root) + blocksize - (char *) de; 1407 memcpy (data1, de, len); 1408 de = (struct ext3_dir_entry_2 *) data1; 1409 top = data1 + len; 1410 while ((char *)(de2 = ext3_next_entry(de)) < top) 1411 de = de2; 1412 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de); 1413 /* Initialize the root; the dot dirents already exist */ 1414 de = (struct ext3_dir_entry_2 *) (&root->dotdot); 1415 de->rec_len = ext3_rec_len_to_disk(blocksize - EXT3_DIR_REC_LEN(2)); 1416 memset (&root->info, 0, sizeof(root->info)); 1417 root->info.info_length = sizeof(root->info); 1418 root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 1419 entries = root->entries; 1420 dx_set_block (entries, 1); 1421 dx_set_count (entries, 1); 1422 dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info))); 1423 1424 /* Initialize as for dx_probe */ 1425 hinfo.hash_version = root->info.hash_version; 1426 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 1427 ext3fs_dirhash(name, namelen, &hinfo); 1428 frame = frames; 1429 frame->entries = entries; 1430 frame->at = entries; 1431 frame->bh = bh; 1432 bh = bh2; 1433 de = do_split(handle,dir, &bh, frame, &hinfo, &retval); 1434 dx_release (frames); 1435 if (!(de)) 1436 return retval; 1437 1438 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1439} 1440 1441/* 1442 * ext3_add_entry() 1443 * 1444 * adds a file entry to the specified directory, using the same 1445 * semantics as ext3_find_entry(). It returns NULL if it failed. 1446 * 1447 * NOTE!! The inode part of 'de' is left at 0 - which means you 1448 * may not sleep between calling this and putting something into 1449 * the entry, as someone else might have used it while you slept. 1450 */ 1451static int ext3_add_entry (handle_t *handle, struct dentry *dentry, 1452 struct inode *inode) 1453{ 1454 struct inode *dir = dentry->d_parent->d_inode; 1455 unsigned long offset; 1456 struct buffer_head * bh; 1457 struct ext3_dir_entry_2 *de; 1458 struct super_block * sb; 1459 int retval; 1460 int dx_fallback=0; 1461 unsigned blocksize; 1462 u32 block, blocks; 1463 1464 sb = dir->i_sb; 1465 blocksize = sb->s_blocksize; 1466 if (!dentry->d_name.len) 1467 return -EINVAL; 1468 if (is_dx(dir)) { 1469 retval = ext3_dx_add_entry(handle, dentry, inode); 1470 if (!retval || (retval != ERR_BAD_DX_DIR)) 1471 return retval; 1472 EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL; 1473 dx_fallback++; 1474 ext3_mark_inode_dirty(handle, dir); 1475 } 1476 blocks = dir->i_size >> sb->s_blocksize_bits; 1477 for (block = 0, offset = 0; block < blocks; block++) { 1478 bh = ext3_bread(handle, dir, block, 0, &retval); 1479 if(!bh) 1480 return retval; 1481 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1482 if (retval != -ENOSPC) 1483 return retval; 1484 1485 if (blocks == 1 && !dx_fallback && 1486 EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) 1487 return make_indexed_dir(handle, dentry, inode, bh); 1488 brelse(bh); 1489 } 1490 bh = ext3_append(handle, dir, &block, &retval); 1491 if (!bh) 1492 return retval; 1493 de = (struct ext3_dir_entry_2 *) bh->b_data; 1494 de->inode = 0; 1495 de->rec_len = ext3_rec_len_to_disk(blocksize); 1496 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1497} 1498 1499/* 1500 * Returns 0 for success, or a negative error value 1501 */ 1502static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, 1503 struct inode *inode) 1504{ 1505 struct dx_frame frames[2], *frame; 1506 struct dx_entry *entries, *at; 1507 struct dx_hash_info hinfo; 1508 struct buffer_head * bh; 1509 struct inode *dir = dentry->d_parent->d_inode; 1510 struct super_block * sb = dir->i_sb; 1511 struct ext3_dir_entry_2 *de; 1512 int err; 1513 1514 frame = dx_probe(dentry, NULL, &hinfo, frames, &err); 1515 if (!frame) 1516 return err; 1517 entries = frame->entries; 1518 at = frame->at; 1519 1520 if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err))) 1521 goto cleanup; 1522 1523 BUFFER_TRACE(bh, "get_write_access"); 1524 err = ext3_journal_get_write_access(handle, bh); 1525 if (err) 1526 goto journal_error; 1527 1528 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1529 if (err != -ENOSPC) { 1530 bh = NULL; 1531 goto cleanup; 1532 } 1533 1534 /* Block full, should compress but for now just split */ 1535 dxtrace(printk("using %u of %u node entries\n", 1536 dx_get_count(entries), dx_get_limit(entries))); 1537 /* Need to split index? */ 1538 if (dx_get_count(entries) == dx_get_limit(entries)) { 1539 u32 newblock; 1540 unsigned icount = dx_get_count(entries); 1541 int levels = frame - frames; 1542 struct dx_entry *entries2; 1543 struct dx_node *node2; 1544 struct buffer_head *bh2; 1545 1546 if (levels && (dx_get_count(frames->entries) == 1547 dx_get_limit(frames->entries))) { 1548 ext3_warning(sb, __FUNCTION__, 1549 "Directory index full!"); 1550 err = -ENOSPC; 1551 goto cleanup; 1552 } 1553 bh2 = ext3_append (handle, dir, &newblock, &err); 1554 if (!(bh2)) 1555 goto cleanup; 1556 node2 = (struct dx_node *)(bh2->b_data); 1557 entries2 = node2->entries; 1558 node2->fake.rec_len = ext3_rec_len_to_disk(sb->s_blocksize); 1559 node2->fake.inode = 0; 1560 BUFFER_TRACE(frame->bh, "get_write_access"); 1561 err = ext3_journal_get_write_access(handle, frame->bh); 1562 if (err) 1563 goto journal_error; 1564 if (levels) { 1565 unsigned icount1 = icount/2, icount2 = icount - icount1; 1566 unsigned hash2 = dx_get_hash(entries + icount1); 1567 dxtrace(printk("Split index %i/%i\n", icount1, icount2)); 1568 1569 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 1570 err = ext3_journal_get_write_access(handle, 1571 frames[0].bh); 1572 if (err) 1573 goto journal_error; 1574 1575 memcpy ((char *) entries2, (char *) (entries + icount1), 1576 icount2 * sizeof(struct dx_entry)); 1577 dx_set_count (entries, icount1); 1578 dx_set_count (entries2, icount2); 1579 dx_set_limit (entries2, dx_node_limit(dir)); 1580 1581 /* Which index block gets the new entry? */ 1582 if (at - entries >= icount1) { 1583 frame->at = at = at - entries - icount1 + entries2; 1584 frame->entries = entries = entries2; 1585 swap(frame->bh, bh2); 1586 } 1587 dx_insert_block (frames + 0, hash2, newblock); 1588 dxtrace(dx_show_index ("node", frames[1].entries)); 1589 dxtrace(dx_show_index ("node", 1590 ((struct dx_node *) bh2->b_data)->entries)); 1591 err = ext3_journal_dirty_metadata(handle, bh2); 1592 if (err) 1593 goto journal_error; 1594 brelse (bh2); 1595 } else { 1596 dxtrace(printk("Creating second level index...\n")); 1597 memcpy((char *) entries2, (char *) entries, 1598 icount * sizeof(struct dx_entry)); 1599 dx_set_limit(entries2, dx_node_limit(dir)); 1600 1601 /* Set up root */ 1602 dx_set_count(entries, 1); 1603 dx_set_block(entries + 0, newblock); 1604 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1; 1605 1606 /* Add new access path frame */ 1607 frame = frames + 1; 1608 frame->at = at = at - entries + entries2; 1609 frame->entries = entries = entries2; 1610 frame->bh = bh2; 1611 err = ext3_journal_get_write_access(handle, 1612 frame->bh); 1613 if (err) 1614 goto journal_error; 1615 } 1616 ext3_journal_dirty_metadata(handle, frames[0].bh); 1617 } 1618 de = do_split(handle, dir, &bh, frame, &hinfo, &err); 1619 if (!de) 1620 goto cleanup; 1621 err = add_dirent_to_buf(handle, dentry, inode, de, bh); 1622 bh = NULL; 1623 goto cleanup; 1624 1625journal_error: 1626 ext3_std_error(dir->i_sb, err); 1627cleanup: 1628 if (bh) 1629 brelse(bh); 1630 dx_release(frames); 1631 return err; 1632} 1633 1634/* 1635 * ext3_delete_entry deletes a directory entry by merging it with the 1636 * previous entry 1637 */ 1638static int ext3_delete_entry (handle_t *handle, 1639 struct inode * dir, 1640 struct ext3_dir_entry_2 * de_del, 1641 struct buffer_head * bh) 1642{ 1643 struct ext3_dir_entry_2 * de, * pde; 1644 int i; 1645 1646 i = 0; 1647 pde = NULL; 1648 de = (struct ext3_dir_entry_2 *) bh->b_data; 1649 while (i < bh->b_size) { 1650 if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i)) 1651 return -EIO; 1652 if (de == de_del) { 1653 BUFFER_TRACE(bh, "get_write_access"); 1654 ext3_journal_get_write_access(handle, bh); 1655 if (pde) 1656 pde->rec_len = ext3_rec_len_to_disk( 1657 ext3_rec_len_from_disk(pde->rec_len) + 1658 ext3_rec_len_from_disk(de->rec_len)); 1659 else 1660 de->inode = 0; 1661 dir->i_version++; 1662 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1663 ext3_journal_dirty_metadata(handle, bh); 1664 return 0; 1665 } 1666 i += ext3_rec_len_from_disk(de->rec_len); 1667 pde = de; 1668 de = ext3_next_entry(de); 1669 } 1670 return -ENOENT; 1671} 1672 1673static int ext3_add_nondir(handle_t *handle, 1674 struct dentry *dentry, struct inode *inode) 1675{ 1676 int err = ext3_add_entry(handle, dentry, inode); 1677 if (!err) { 1678 ext3_mark_inode_dirty(handle, inode); 1679 d_instantiate(dentry, inode); 1680 return 0; 1681 } 1682 drop_nlink(inode); 1683 iput(inode); 1684 return err; 1685} 1686 1687/* 1688 * By the time this is called, we already have created 1689 * the directory cache entry for the new file, but it 1690 * is so far negative - it has no inode. 1691 * 1692 * If the create succeeds, we fill in the inode information 1693 * with d_instantiate(). 1694 */ 1695static int ext3_create (struct inode * dir, struct dentry * dentry, int mode, 1696 struct nameidata *nd) 1697{ 1698 handle_t *handle; 1699 struct inode * inode; 1700 int err, retries = 0; 1701 1702retry: 1703 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1704 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1705 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1706 if (IS_ERR(handle)) 1707 return PTR_ERR(handle); 1708 1709 if (IS_DIRSYNC(dir)) 1710 handle->h_sync = 1; 1711 1712 inode = ext3_new_inode (handle, dir, mode); 1713 err = PTR_ERR(inode); 1714 if (!IS_ERR(inode)) { 1715 inode->i_op = &ext3_file_inode_operations; 1716 inode->i_fop = &ext3_file_operations; 1717 ext3_set_aops(inode); 1718 err = ext3_add_nondir(handle, dentry, inode); 1719 } 1720 ext3_journal_stop(handle); 1721 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1722 goto retry; 1723 return err; 1724} 1725 1726static int ext3_mknod (struct inode * dir, struct dentry *dentry, 1727 int mode, dev_t rdev) 1728{ 1729 handle_t *handle; 1730 struct inode *inode; 1731 int err, retries = 0; 1732 1733 if (!new_valid_dev(rdev)) 1734 return -EINVAL; 1735 1736retry: 1737 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1738 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1739 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1740 if (IS_ERR(handle)) 1741 return PTR_ERR(handle); 1742 1743 if (IS_DIRSYNC(dir)) 1744 handle->h_sync = 1; 1745 1746 inode = ext3_new_inode (handle, dir, mode); 1747 err = PTR_ERR(inode); 1748 if (!IS_ERR(inode)) { 1749 init_special_inode(inode, inode->i_mode, rdev); 1750#ifdef CONFIG_EXT3_FS_XATTR 1751 inode->i_op = &ext3_special_inode_operations; 1752#endif 1753 err = ext3_add_nondir(handle, dentry, inode); 1754 } 1755 ext3_journal_stop(handle); 1756 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1757 goto retry; 1758 return err; 1759} 1760 1761static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode) 1762{ 1763 handle_t *handle; 1764 struct inode * inode; 1765 struct buffer_head * dir_block; 1766 struct ext3_dir_entry_2 * de; 1767 int err, retries = 0; 1768 1769 if (dir->i_nlink >= EXT3_LINK_MAX) 1770 return -EMLINK; 1771 1772retry: 1773 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1774 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1775 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1776 if (IS_ERR(handle)) 1777 return PTR_ERR(handle); 1778 1779 if (IS_DIRSYNC(dir)) 1780 handle->h_sync = 1; 1781 1782 inode = ext3_new_inode (handle, dir, S_IFDIR | mode); 1783 err = PTR_ERR(inode); 1784 if (IS_ERR(inode)) 1785 goto out_stop; 1786 1787 inode->i_op = &ext3_dir_inode_operations; 1788 inode->i_fop = &ext3_dir_operations; 1789 inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize; 1790 dir_block = ext3_bread (handle, inode, 0, 1, &err); 1791 if (!dir_block) { 1792 drop_nlink(inode); /* is this nlink == 0? */ 1793 ext3_mark_inode_dirty(handle, inode); 1794 iput (inode); 1795 goto out_stop; 1796 } 1797 BUFFER_TRACE(dir_block, "get_write_access"); 1798 ext3_journal_get_write_access(handle, dir_block); 1799 de = (struct ext3_dir_entry_2 *) dir_block->b_data; 1800 de->inode = cpu_to_le32(inode->i_ino); 1801 de->name_len = 1; 1802 de->rec_len = ext3_rec_len_to_disk(EXT3_DIR_REC_LEN(de->name_len)); 1803 strcpy (de->name, "."); 1804 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1805 de = ext3_next_entry(de); 1806 de->inode = cpu_to_le32(dir->i_ino); 1807 de->rec_len = ext3_rec_len_to_disk(inode->i_sb->s_blocksize - 1808 EXT3_DIR_REC_LEN(1)); 1809 de->name_len = 2; 1810 strcpy (de->name, ".."); 1811 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1812 inode->i_nlink = 2; 1813 BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata"); 1814 ext3_journal_dirty_metadata(handle, dir_block); 1815 brelse (dir_block); 1816 ext3_mark_inode_dirty(handle, inode); 1817 err = ext3_add_entry (handle, dentry, inode); 1818 if (err) { 1819 inode->i_nlink = 0; 1820 ext3_mark_inode_dirty(handle, inode); 1821 iput (inode); 1822 goto out_stop; 1823 } 1824 inc_nlink(dir); 1825 ext3_update_dx_flag(dir); 1826 ext3_mark_inode_dirty(handle, dir); 1827 d_instantiate(dentry, inode); 1828out_stop: 1829 ext3_journal_stop(handle); 1830 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1831 goto retry; 1832 return err; 1833} 1834 1835/* 1836 * routine to check that the specified directory is empty (for rmdir) 1837 */ 1838static int empty_dir (struct inode * inode) 1839{ 1840 unsigned long offset; 1841 struct buffer_head * bh; 1842 struct ext3_dir_entry_2 * de, * de1; 1843 struct super_block * sb; 1844 int err = 0; 1845 1846 sb = inode->i_sb; 1847 if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) || 1848 !(bh = ext3_bread (NULL, inode, 0, 0, &err))) { 1849 if (err) 1850 ext3_error(inode->i_sb, __FUNCTION__, 1851 "error %d reading directory #%lu offset 0", 1852 err, inode->i_ino); 1853 else 1854 ext3_warning(inode->i_sb, __FUNCTION__, 1855 "bad directory (dir #%lu) - no data block", 1856 inode->i_ino); 1857 return 1; 1858 } 1859 de = (struct ext3_dir_entry_2 *) bh->b_data; 1860 de1 = ext3_next_entry(de); 1861 if (le32_to_cpu(de->inode) != inode->i_ino || 1862 !le32_to_cpu(de1->inode) || 1863 strcmp (".", de->name) || 1864 strcmp ("..", de1->name)) { 1865 ext3_warning (inode->i_sb, "empty_dir", 1866 "bad directory (dir #%lu) - no `.' or `..'", 1867 inode->i_ino); 1868 brelse (bh); 1869 return 1; 1870 } 1871 offset = ext3_rec_len_from_disk(de->rec_len) + 1872 ext3_rec_len_from_disk(de1->rec_len); 1873 de = ext3_next_entry(de1); 1874 while (offset < inode->i_size ) { 1875 if (!bh || 1876 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 1877 err = 0; 1878 brelse (bh); 1879 bh = ext3_bread (NULL, inode, 1880 offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err); 1881 if (!bh) { 1882 if (err) 1883 ext3_error(sb, __FUNCTION__, 1884 "error %d reading directory" 1885 " #%lu offset %lu", 1886 err, inode->i_ino, offset); 1887 offset += sb->s_blocksize; 1888 continue; 1889 } 1890 de = (struct ext3_dir_entry_2 *) bh->b_data; 1891 } 1892 if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) { 1893 de = (struct ext3_dir_entry_2 *)(bh->b_data + 1894 sb->s_blocksize); 1895 offset = (offset | (sb->s_blocksize - 1)) + 1; 1896 continue; 1897 } 1898 if (le32_to_cpu(de->inode)) { 1899 brelse (bh); 1900 return 0; 1901 } 1902 offset += ext3_rec_len_from_disk(de->rec_len); 1903 de = ext3_next_entry(de); 1904 } 1905 brelse (bh); 1906 return 1; 1907} 1908 1909/* ext3_orphan_add() links an unlinked or truncated inode into a list of 1910 * such inodes, starting at the superblock, in case we crash before the 1911 * file is closed/deleted, or in case the inode truncate spans multiple 1912 * transactions and the last transaction is not recovered after a crash. 1913 * 1914 * At filesystem recovery time, we walk this list deleting unlinked 1915 * inodes and truncating linked inodes in ext3_orphan_cleanup(). 1916 */ 1917int ext3_orphan_add(handle_t *handle, struct inode *inode) 1918{ 1919 struct super_block *sb = inode->i_sb; 1920 struct ext3_iloc iloc; 1921 int err = 0, rc; 1922 1923 lock_super(sb); 1924 if (!list_empty(&EXT3_I(inode)->i_orphan)) 1925 goto out_unlock; 1926 1927 /* Orphan handling is only valid for files with data blocks 1928 * being truncated, or files being unlinked. */ 1929 1930 /* @@@ FIXME: Observation from aviro: 1931 * I think I can trigger J_ASSERT in ext3_orphan_add(). We block 1932 * here (on lock_super()), so race with ext3_link() which might bump 1933 * ->i_nlink. For, say it, character device. Not a regular file, 1934 * not a directory, not a symlink and ->i_nlink > 0. 1935 */ 1936 J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 1937 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 1938 1939 BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access"); 1940 err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh); 1941 if (err) 1942 goto out_unlock; 1943 1944 err = ext3_reserve_inode_write(handle, inode, &iloc); 1945 if (err) 1946 goto out_unlock; 1947 1948 /* Insert this inode at the head of the on-disk orphan list... */ 1949 NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan); 1950 EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 1951 err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh); 1952 rc = ext3_mark_iloc_dirty(handle, inode, &iloc); 1953 if (!err) 1954 err = rc; 1955 1956 /* Only add to the head of the in-memory list if all the 1957 * previous operations succeeded. If the orphan_add is going to 1958 * fail (possibly taking the journal offline), we can't risk 1959 * leaving the inode on the orphan list: stray orphan-list 1960 * entries can cause panics at unmount time. 1961 * 1962 * This is safe: on error we're going to ignore the orphan list 1963 * anyway on the next recovery. */ 1964 if (!err) 1965 list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan); 1966 1967 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 1968 jbd_debug(4, "orphan inode %lu will point to %d\n", 1969 inode->i_ino, NEXT_ORPHAN(inode)); 1970out_unlock: 1971 unlock_super(sb); 1972 ext3_std_error(inode->i_sb, err); 1973 return err; 1974} 1975 1976/* 1977 * ext3_orphan_del() removes an unlinked or truncated inode from the list 1978 * of such inodes stored on disk, because it is finally being cleaned up. 1979 */ 1980int ext3_orphan_del(handle_t *handle, struct inode *inode) 1981{ 1982 struct list_head *prev; 1983 struct ext3_inode_info *ei = EXT3_I(inode); 1984 struct ext3_sb_info *sbi; 1985 unsigned long ino_next; 1986 struct ext3_iloc iloc; 1987 int err = 0; 1988 1989 lock_super(inode->i_sb); 1990 if (list_empty(&ei->i_orphan)) { 1991 unlock_super(inode->i_sb); 1992 return 0; 1993 } 1994 1995 ino_next = NEXT_ORPHAN(inode); 1996 prev = ei->i_orphan.prev; 1997 sbi = EXT3_SB(inode->i_sb); 1998 1999 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 2000 2001 list_del_init(&ei->i_orphan); 2002 2003 /* If we're on an error path, we may not have a valid 2004 * transaction handle with which to update the orphan list on 2005 * disk, but we still need to remove the inode from the linked 2006 * list in memory. */ 2007 if (!handle) 2008 goto out; 2009 2010 err = ext3_reserve_inode_write(handle, inode, &iloc); 2011 if (err) 2012 goto out_err; 2013 2014 if (prev == &sbi->s_orphan) { 2015 jbd_debug(4, "superblock will point to %lu\n", ino_next); 2016 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2017 err = ext3_journal_get_write_access(handle, sbi->s_sbh); 2018 if (err) 2019 goto out_brelse; 2020 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 2021 err = ext3_journal_dirty_metadata(handle, sbi->s_sbh); 2022 } else { 2023 struct ext3_iloc iloc2; 2024 struct inode *i_prev = 2025 &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode; 2026 2027 jbd_debug(4, "orphan inode %lu will point to %lu\n", 2028 i_prev->i_ino, ino_next); 2029 err = ext3_reserve_inode_write(handle, i_prev, &iloc2); 2030 if (err) 2031 goto out_brelse; 2032 NEXT_ORPHAN(i_prev) = ino_next; 2033 err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2); 2034 } 2035 if (err) 2036 goto out_brelse; 2037 NEXT_ORPHAN(inode) = 0; 2038 err = ext3_mark_iloc_dirty(handle, inode, &iloc); 2039 2040out_err: 2041 ext3_std_error(inode->i_sb, err); 2042out: 2043 unlock_super(inode->i_sb); 2044 return err; 2045 2046out_brelse: 2047 brelse(iloc.bh); 2048 goto out_err; 2049} 2050 2051static int ext3_rmdir (struct inode * dir, struct dentry *dentry) 2052{ 2053 int retval; 2054 struct inode * inode; 2055 struct buffer_head * bh; 2056 struct ext3_dir_entry_2 * de; 2057 handle_t *handle; 2058 2059 /* Initialize quotas before so that eventual writes go in 2060 * separate transaction */ 2061 DQUOT_INIT(dentry->d_inode); 2062 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2063 if (IS_ERR(handle)) 2064 return PTR_ERR(handle); 2065 2066 retval = -ENOENT; 2067 bh = ext3_find_entry (dentry, &de); 2068 if (!bh) 2069 goto end_rmdir; 2070 2071 if (IS_DIRSYNC(dir)) 2072 handle->h_sync = 1; 2073 2074 inode = dentry->d_inode; 2075 2076 retval = -EIO; 2077 if (le32_to_cpu(de->inode) != inode->i_ino) 2078 goto end_rmdir; 2079 2080 retval = -ENOTEMPTY; 2081 if (!empty_dir (inode)) 2082 goto end_rmdir; 2083 2084 retval = ext3_delete_entry(handle, dir, de, bh); 2085 if (retval) 2086 goto end_rmdir; 2087 if (inode->i_nlink != 2) 2088 ext3_warning (inode->i_sb, "ext3_rmdir", 2089 "empty directory has nlink!=2 (%d)", 2090 inode->i_nlink); 2091 inode->i_version++; 2092 clear_nlink(inode); 2093 /* There's no need to set i_disksize: the fact that i_nlink is 2094 * zero will ensure that the right thing happens during any 2095 * recovery. */ 2096 inode->i_size = 0; 2097 ext3_orphan_add(handle, inode); 2098 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2099 ext3_mark_inode_dirty(handle, inode); 2100 drop_nlink(dir); 2101 ext3_update_dx_flag(dir); 2102 ext3_mark_inode_dirty(handle, dir); 2103 2104end_rmdir: 2105 ext3_journal_stop(handle); 2106 brelse (bh); 2107 return retval; 2108} 2109 2110static int ext3_unlink(struct inode * dir, struct dentry *dentry) 2111{ 2112 int retval; 2113 struct inode * inode; 2114 struct buffer_head * bh; 2115 struct ext3_dir_entry_2 * de; 2116 handle_t *handle; 2117 2118 /* Initialize quotas before so that eventual writes go 2119 * in separate transaction */ 2120 DQUOT_INIT(dentry->d_inode); 2121 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2122 if (IS_ERR(handle)) 2123 return PTR_ERR(handle); 2124 2125 if (IS_DIRSYNC(dir)) 2126 handle->h_sync = 1; 2127 2128 retval = -ENOENT; 2129 bh = ext3_find_entry (dentry, &de); 2130 if (!bh) 2131 goto end_unlink; 2132 2133 inode = dentry->d_inode; 2134 2135 retval = -EIO; 2136 if (le32_to_cpu(de->inode) != inode->i_ino) 2137 goto end_unlink; 2138 2139 if (!inode->i_nlink) { 2140 ext3_warning (inode->i_sb, "ext3_unlink", 2141 "Deleting nonexistent file (%lu), %d", 2142 inode->i_ino, inode->i_nlink); 2143 inode->i_nlink = 1; 2144 } 2145 retval = ext3_delete_entry(handle, dir, de, bh); 2146 if (retval) 2147 goto end_unlink; 2148 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2149 ext3_update_dx_flag(dir); 2150 ext3_mark_inode_dirty(handle, dir); 2151 drop_nlink(inode); 2152 if (!inode->i_nlink) 2153 ext3_orphan_add(handle, inode); 2154 inode->i_ctime = dir->i_ctime; 2155 ext3_mark_inode_dirty(handle, inode); 2156 retval = 0; 2157 2158end_unlink: 2159 ext3_journal_stop(handle); 2160 brelse (bh); 2161 return retval; 2162} 2163 2164static int ext3_symlink (struct inode * dir, 2165 struct dentry *dentry, const char * symname) 2166{ 2167 handle_t *handle; 2168 struct inode * inode; 2169 int l, err, retries = 0; 2170 2171 l = strlen(symname)+1; 2172 if (l > dir->i_sb->s_blocksize) 2173 return -ENAMETOOLONG; 2174 2175retry: 2176 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2177 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 5 + 2178 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 2179 if (IS_ERR(handle)) 2180 return PTR_ERR(handle); 2181 2182 if (IS_DIRSYNC(dir)) 2183 handle->h_sync = 1; 2184 2185 inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO); 2186 err = PTR_ERR(inode); 2187 if (IS_ERR(inode)) 2188 goto out_stop; 2189 2190 if (l > sizeof (EXT3_I(inode)->i_data)) { 2191 inode->i_op = &ext3_symlink_inode_operations; 2192 ext3_set_aops(inode); 2193 /* 2194 * page_symlink() calls into ext3_prepare/commit_write. 2195 * We have a transaction open. All is sweetness. It also sets 2196 * i_size in generic_commit_write(). 2197 */ 2198 err = __page_symlink(inode, symname, l, 2199 mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS); 2200 if (err) { 2201 drop_nlink(inode); 2202 ext3_mark_inode_dirty(handle, inode); 2203 iput (inode); 2204 goto out_stop; 2205 } 2206 } else { 2207 inode->i_op = &ext3_fast_symlink_inode_operations; 2208 memcpy((char*)&EXT3_I(inode)->i_data,symname,l); 2209 inode->i_size = l-1; 2210 } 2211 EXT3_I(inode)->i_disksize = inode->i_size; 2212 err = ext3_add_nondir(handle, dentry, inode); 2213out_stop: 2214 ext3_journal_stop(handle); 2215 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2216 goto retry; 2217 return err; 2218} 2219 2220static int ext3_link (struct dentry * old_dentry, 2221 struct inode * dir, struct dentry *dentry) 2222{ 2223 handle_t *handle; 2224 struct inode *inode = old_dentry->d_inode; 2225 int err, retries = 0; 2226 2227 if (inode->i_nlink >= EXT3_LINK_MAX) 2228 return -EMLINK; 2229 /* 2230 * Return -ENOENT if we've raced with unlink and i_nlink is 0. Doing 2231 * otherwise has the potential to corrupt the orphan inode list. 2232 */ 2233 if (inode->i_nlink == 0) 2234 return -ENOENT; 2235 2236retry: 2237 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2238 EXT3_INDEX_EXTRA_TRANS_BLOCKS); 2239 if (IS_ERR(handle)) 2240 return PTR_ERR(handle); 2241 2242 if (IS_DIRSYNC(dir)) 2243 handle->h_sync = 1; 2244 2245 inode->i_ctime = CURRENT_TIME_SEC; 2246 inc_nlink(inode); 2247 atomic_inc(&inode->i_count); 2248 2249 err = ext3_add_nondir(handle, dentry, inode); 2250 ext3_journal_stop(handle); 2251 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2252 goto retry; 2253 return err; 2254} 2255 2256#define PARENT_INO(buffer) \ 2257 (ext3_next_entry((struct ext3_dir_entry_2 *)(buffer))->inode) 2258 2259/* 2260 * Anybody can rename anything with this: the permission checks are left to the 2261 * higher-level routines. 2262 */ 2263static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, 2264 struct inode * new_dir,struct dentry *new_dentry) 2265{ 2266 handle_t *handle; 2267 struct inode * old_inode, * new_inode; 2268 struct buffer_head * old_bh, * new_bh, * dir_bh; 2269 struct ext3_dir_entry_2 * old_de, * new_de; 2270 int retval; 2271 2272 old_bh = new_bh = dir_bh = NULL; 2273 2274 /* Initialize quotas before so that eventual writes go 2275 * in separate transaction */ 2276 if (new_dentry->d_inode) 2277 DQUOT_INIT(new_dentry->d_inode); 2278 handle = ext3_journal_start(old_dir, 2 * 2279 EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) + 2280 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2); 2281 if (IS_ERR(handle)) 2282 return PTR_ERR(handle); 2283 2284 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) 2285 handle->h_sync = 1; 2286 2287 old_bh = ext3_find_entry (old_dentry, &old_de); 2288 /* 2289 * Check for inode number is _not_ due to possible IO errors. 2290 * We might rmdir the source, keep it as pwd of some process 2291 * and merrily kill the link to whatever was created under the 2292 * same name. Goodbye sticky bit ;-< 2293 */ 2294 old_inode = old_dentry->d_inode; 2295 retval = -ENOENT; 2296 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino) 2297 goto end_rename; 2298 2299 new_inode = new_dentry->d_inode; 2300 new_bh = ext3_find_entry (new_dentry, &new_de); 2301 if (new_bh) { 2302 if (!new_inode) { 2303 brelse (new_bh); 2304 new_bh = NULL; 2305 } 2306 } 2307 if (S_ISDIR(old_inode->i_mode)) { 2308 if (new_inode) { 2309 retval = -ENOTEMPTY; 2310 if (!empty_dir (new_inode)) 2311 goto end_rename; 2312 } 2313 retval = -EIO; 2314 dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval); 2315 if (!dir_bh) 2316 goto end_rename; 2317 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino) 2318 goto end_rename; 2319 retval = -EMLINK; 2320 if (!new_inode && new_dir!=old_dir && 2321 new_dir->i_nlink >= EXT3_LINK_MAX) 2322 goto end_rename; 2323 } 2324 if (!new_bh) { 2325 retval = ext3_add_entry (handle, new_dentry, old_inode); 2326 if (retval) 2327 goto end_rename; 2328 } else { 2329 BUFFER_TRACE(new_bh, "get write access"); 2330 ext3_journal_get_write_access(handle, new_bh); 2331 new_de->inode = cpu_to_le32(old_inode->i_ino); 2332 if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb, 2333 EXT3_FEATURE_INCOMPAT_FILETYPE)) 2334 new_de->file_type = old_de->file_type; 2335 new_dir->i_version++; 2336 BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata"); 2337 ext3_journal_dirty_metadata(handle, new_bh); 2338 brelse(new_bh); 2339 new_bh = NULL; 2340 } 2341 2342 /* 2343 * Like most other Unix systems, set the ctime for inodes on a 2344 * rename. 2345 */ 2346 old_inode->i_ctime = CURRENT_TIME_SEC; 2347 ext3_mark_inode_dirty(handle, old_inode); 2348 2349 /* 2350 * ok, that's it 2351 */ 2352 if (le32_to_cpu(old_de->inode) != old_inode->i_ino || 2353 old_de->name_len != old_dentry->d_name.len || 2354 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) || 2355 (retval = ext3_delete_entry(handle, old_dir, 2356 old_de, old_bh)) == -ENOENT) { 2357 /* old_de could have moved from under us during htree split, so 2358 * make sure that we are deleting the right entry. We might 2359 * also be pointing to a stale entry in the unused part of 2360 * old_bh so just checking inum and the name isn't enough. */ 2361 struct buffer_head *old_bh2; 2362 struct ext3_dir_entry_2 *old_de2; 2363 2364 old_bh2 = ext3_find_entry(old_dentry, &old_de2); 2365 if (old_bh2) { 2366 retval = ext3_delete_entry(handle, old_dir, 2367 old_de2, old_bh2); 2368 brelse(old_bh2); 2369 } 2370 } 2371 if (retval) { 2372 ext3_warning(old_dir->i_sb, "ext3_rename", 2373 "Deleting old file (%lu), %d, error=%d", 2374 old_dir->i_ino, old_dir->i_nlink, retval); 2375 } 2376 2377 if (new_inode) { 2378 drop_nlink(new_inode); 2379 new_inode->i_ctime = CURRENT_TIME_SEC; 2380 } 2381 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; 2382 ext3_update_dx_flag(old_dir); 2383 if (dir_bh) { 2384 BUFFER_TRACE(dir_bh, "get_write_access"); 2385 ext3_journal_get_write_access(handle, dir_bh); 2386 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino); 2387 BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata"); 2388 ext3_journal_dirty_metadata(handle, dir_bh); 2389 drop_nlink(old_dir); 2390 if (new_inode) { 2391 drop_nlink(new_inode); 2392 } else { 2393 inc_nlink(new_dir); 2394 ext3_update_dx_flag(new_dir); 2395 ext3_mark_inode_dirty(handle, new_dir); 2396 } 2397 } 2398 ext3_mark_inode_dirty(handle, old_dir); 2399 if (new_inode) { 2400 ext3_mark_inode_dirty(handle, new_inode); 2401 if (!new_inode->i_nlink) 2402 ext3_orphan_add(handle, new_inode); 2403 } 2404 retval = 0; 2405 2406end_rename: 2407 brelse (dir_bh); 2408 brelse (old_bh); 2409 brelse (new_bh); 2410 ext3_journal_stop(handle); 2411 return retval; 2412} 2413 2414/* 2415 * directories can handle most operations... 2416 */ 2417const struct inode_operations ext3_dir_inode_operations = { 2418 .create = ext3_create, 2419 .lookup = ext3_lookup, 2420 .link = ext3_link, 2421 .unlink = ext3_unlink, 2422 .symlink = ext3_symlink, 2423 .mkdir = ext3_mkdir, 2424 .rmdir = ext3_rmdir, 2425 .mknod = ext3_mknod, 2426 .rename = ext3_rename, 2427 .setattr = ext3_setattr, 2428#ifdef CONFIG_EXT3_FS_XATTR 2429 .setxattr = generic_setxattr, 2430 .getxattr = generic_getxattr, 2431 .listxattr = ext3_listxattr, 2432 .removexattr = generic_removexattr, 2433#endif 2434 .permission = ext3_permission, 2435}; 2436 2437const struct inode_operations ext3_special_inode_operations = { 2438 .setattr = ext3_setattr, 2439#ifdef CONFIG_EXT3_FS_XATTR 2440 .setxattr = generic_setxattr, 2441 .getxattr = generic_getxattr, 2442 .listxattr = ext3_listxattr, 2443 .removexattr = generic_removexattr, 2444#endif 2445 .permission = ext3_permission, 2446}; 2447