namei.c revision 65299a3b788bd274bed92f9fa3232082c9f3ea70
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#include <trace/events/ext3.h> 40 41#include "namei.h" 42#include "xattr.h" 43#include "acl.h" 44 45/* 46 * define how far ahead to read directories while searching them. 47 */ 48#define NAMEI_RA_CHUNKS 2 49#define NAMEI_RA_BLOCKS 4 50#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) 51#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b)) 52 53static struct buffer_head *ext3_append(handle_t *handle, 54 struct inode *inode, 55 u32 *block, int *err) 56{ 57 struct buffer_head *bh; 58 59 *block = inode->i_size >> inode->i_sb->s_blocksize_bits; 60 61 bh = ext3_bread(handle, inode, *block, 1, err); 62 if (bh) { 63 inode->i_size += inode->i_sb->s_blocksize; 64 EXT3_I(inode)->i_disksize = inode->i_size; 65 *err = ext3_journal_get_write_access(handle, bh); 66 if (*err) { 67 brelse(bh); 68 bh = NULL; 69 } 70 } 71 return bh; 72} 73 74#ifndef assert 75#define assert(test) J_ASSERT(test) 76#endif 77 78#ifdef DX_DEBUG 79#define dxtrace(command) command 80#else 81#define dxtrace(command) 82#endif 83 84struct fake_dirent 85{ 86 __le32 inode; 87 __le16 rec_len; 88 u8 name_len; 89 u8 file_type; 90}; 91 92struct dx_countlimit 93{ 94 __le16 limit; 95 __le16 count; 96}; 97 98struct dx_entry 99{ 100 __le32 hash; 101 __le32 block; 102}; 103 104/* 105 * dx_root_info is laid out so that if it should somehow get overlaid by a 106 * dirent the two low bits of the hash version will be zero. Therefore, the 107 * hash version mod 4 should never be 0. Sincerely, the paranoia department. 108 */ 109 110struct dx_root 111{ 112 struct fake_dirent dot; 113 char dot_name[4]; 114 struct fake_dirent dotdot; 115 char dotdot_name[4]; 116 struct dx_root_info 117 { 118 __le32 reserved_zero; 119 u8 hash_version; 120 u8 info_length; /* 8 */ 121 u8 indirect_levels; 122 u8 unused_flags; 123 } 124 info; 125 struct dx_entry entries[0]; 126}; 127 128struct dx_node 129{ 130 struct fake_dirent fake; 131 struct dx_entry entries[0]; 132}; 133 134 135struct dx_frame 136{ 137 struct buffer_head *bh; 138 struct dx_entry *entries; 139 struct dx_entry *at; 140}; 141 142struct dx_map_entry 143{ 144 u32 hash; 145 u16 offs; 146 u16 size; 147}; 148 149static inline unsigned dx_get_block (struct dx_entry *entry); 150static void dx_set_block (struct dx_entry *entry, unsigned value); 151static inline unsigned dx_get_hash (struct dx_entry *entry); 152static void dx_set_hash (struct dx_entry *entry, unsigned value); 153static unsigned dx_get_count (struct dx_entry *entries); 154static unsigned dx_get_limit (struct dx_entry *entries); 155static void dx_set_count (struct dx_entry *entries, unsigned value); 156static void dx_set_limit (struct dx_entry *entries, unsigned value); 157static unsigned dx_root_limit (struct inode *dir, unsigned infosize); 158static unsigned dx_node_limit (struct inode *dir); 159static struct dx_frame *dx_probe(struct qstr *entry, 160 struct inode *dir, 161 struct dx_hash_info *hinfo, 162 struct dx_frame *frame, 163 int *err); 164static void dx_release (struct dx_frame *frames); 165static int dx_make_map(struct ext3_dir_entry_2 *de, unsigned blocksize, 166 struct dx_hash_info *hinfo, struct dx_map_entry map[]); 167static void dx_sort_map(struct dx_map_entry *map, unsigned count); 168static struct ext3_dir_entry_2 *dx_move_dirents (char *from, char *to, 169 struct dx_map_entry *offsets, int count); 170static struct ext3_dir_entry_2 *dx_pack_dirents(char *base, unsigned blocksize); 171static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block); 172static int ext3_htree_next_block(struct inode *dir, __u32 hash, 173 struct dx_frame *frame, 174 struct dx_frame *frames, 175 __u32 *start_hash); 176static struct buffer_head * ext3_dx_find_entry(struct inode *dir, 177 struct qstr *entry, struct ext3_dir_entry_2 **res_dir, 178 int *err); 179static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, 180 struct inode *inode); 181 182/* 183 * p is at least 6 bytes before the end of page 184 */ 185static inline struct ext3_dir_entry_2 * 186ext3_next_entry(struct ext3_dir_entry_2 *p) 187{ 188 return (struct ext3_dir_entry_2 *)((char *)p + 189 ext3_rec_len_from_disk(p->rec_len)); 190} 191 192/* 193 * Future: use high four bits of block for coalesce-on-delete flags 194 * Mask them off for now. 195 */ 196 197static inline unsigned dx_get_block (struct dx_entry *entry) 198{ 199 return le32_to_cpu(entry->block) & 0x00ffffff; 200} 201 202static inline void dx_set_block (struct dx_entry *entry, unsigned value) 203{ 204 entry->block = cpu_to_le32(value); 205} 206 207static inline unsigned dx_get_hash (struct dx_entry *entry) 208{ 209 return le32_to_cpu(entry->hash); 210} 211 212static inline void dx_set_hash (struct dx_entry *entry, unsigned value) 213{ 214 entry->hash = cpu_to_le32(value); 215} 216 217static inline unsigned dx_get_count (struct dx_entry *entries) 218{ 219 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 220} 221 222static inline unsigned dx_get_limit (struct dx_entry *entries) 223{ 224 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 225} 226 227static inline void dx_set_count (struct dx_entry *entries, unsigned value) 228{ 229 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 230} 231 232static inline void dx_set_limit (struct dx_entry *entries, unsigned value) 233{ 234 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 235} 236 237static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize) 238{ 239 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) - 240 EXT3_DIR_REC_LEN(2) - infosize; 241 return entry_space / sizeof(struct dx_entry); 242} 243 244static inline unsigned dx_node_limit (struct inode *dir) 245{ 246 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0); 247 return entry_space / sizeof(struct dx_entry); 248} 249 250/* 251 * Debug 252 */ 253#ifdef DX_DEBUG 254static void dx_show_index (char * label, struct dx_entry *entries) 255{ 256 int i, n = dx_get_count (entries); 257 printk("%s index ", label); 258 for (i = 0; i < n; i++) 259 { 260 printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i)); 261 } 262 printk("\n"); 263} 264 265struct stats 266{ 267 unsigned names; 268 unsigned space; 269 unsigned bcount; 270}; 271 272static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de, 273 int size, int show_names) 274{ 275 unsigned names = 0, space = 0; 276 char *base = (char *) de; 277 struct dx_hash_info h = *hinfo; 278 279 printk("names: "); 280 while ((char *) de < base + size) 281 { 282 if (de->inode) 283 { 284 if (show_names) 285 { 286 int len = de->name_len; 287 char *name = de->name; 288 while (len--) printk("%c", *name++); 289 ext3fs_dirhash(de->name, de->name_len, &h); 290 printk(":%x.%u ", h.hash, 291 (unsigned) ((char *) de - base)); 292 } 293 space += EXT3_DIR_REC_LEN(de->name_len); 294 names++; 295 } 296 de = ext3_next_entry(de); 297 } 298 printk("(%i)\n", names); 299 return (struct stats) { names, space, 1 }; 300} 301 302struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 303 struct dx_entry *entries, int levels) 304{ 305 unsigned blocksize = dir->i_sb->s_blocksize; 306 unsigned count = dx_get_count (entries), names = 0, space = 0, i; 307 unsigned bcount = 0; 308 struct buffer_head *bh; 309 int err; 310 printk("%i indexed blocks...\n", count); 311 for (i = 0; i < count; i++, entries++) 312 { 313 u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0; 314 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 315 struct stats stats; 316 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 317 if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue; 318 stats = levels? 319 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 320 dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0); 321 names += stats.names; 322 space += stats.space; 323 bcount += stats.bcount; 324 brelse (bh); 325 } 326 if (bcount) 327 printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ", 328 names, space/bcount,(space/bcount)*100/blocksize); 329 return (struct stats) { names, space, bcount}; 330} 331#endif /* DX_DEBUG */ 332 333/* 334 * Probe for a directory leaf block to search. 335 * 336 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 337 * error in the directory index, and the caller should fall back to 338 * searching the directory normally. The callers of dx_probe **MUST** 339 * check for this error code, and make sure it never gets reflected 340 * back to userspace. 341 */ 342static struct dx_frame * 343dx_probe(struct qstr *entry, struct inode *dir, 344 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err) 345{ 346 unsigned count, indirect; 347 struct dx_entry *at, *entries, *p, *q, *m; 348 struct dx_root *root; 349 struct buffer_head *bh; 350 struct dx_frame *frame = frame_in; 351 u32 hash; 352 353 frame->bh = NULL; 354 if (!(bh = ext3_bread (NULL,dir, 0, 0, err))) 355 goto fail; 356 root = (struct dx_root *) bh->b_data; 357 if (root->info.hash_version != DX_HASH_TEA && 358 root->info.hash_version != DX_HASH_HALF_MD4 && 359 root->info.hash_version != DX_HASH_LEGACY) { 360 ext3_warning(dir->i_sb, __func__, 361 "Unrecognised inode hash code %d", 362 root->info.hash_version); 363 brelse(bh); 364 *err = ERR_BAD_DX_DIR; 365 goto fail; 366 } 367 hinfo->hash_version = root->info.hash_version; 368 if (hinfo->hash_version <= DX_HASH_TEA) 369 hinfo->hash_version += EXT3_SB(dir->i_sb)->s_hash_unsigned; 370 hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed; 371 if (entry) 372 ext3fs_dirhash(entry->name, entry->len, hinfo); 373 hash = hinfo->hash; 374 375 if (root->info.unused_flags & 1) { 376 ext3_warning(dir->i_sb, __func__, 377 "Unimplemented inode hash flags: %#06x", 378 root->info.unused_flags); 379 brelse(bh); 380 *err = ERR_BAD_DX_DIR; 381 goto fail; 382 } 383 384 if ((indirect = root->info.indirect_levels) > 1) { 385 ext3_warning(dir->i_sb, __func__, 386 "Unimplemented inode hash depth: %#06x", 387 root->info.indirect_levels); 388 brelse(bh); 389 *err = ERR_BAD_DX_DIR; 390 goto fail; 391 } 392 393 entries = (struct dx_entry *) (((char *)&root->info) + 394 root->info.info_length); 395 396 if (dx_get_limit(entries) != dx_root_limit(dir, 397 root->info.info_length)) { 398 ext3_warning(dir->i_sb, __func__, 399 "dx entry: limit != root limit"); 400 brelse(bh); 401 *err = ERR_BAD_DX_DIR; 402 goto fail; 403 } 404 405 dxtrace (printk("Look up %x", hash)); 406 while (1) 407 { 408 count = dx_get_count(entries); 409 if (!count || count > dx_get_limit(entries)) { 410 ext3_warning(dir->i_sb, __func__, 411 "dx entry: no count or count > limit"); 412 brelse(bh); 413 *err = ERR_BAD_DX_DIR; 414 goto fail2; 415 } 416 417 p = entries + 1; 418 q = entries + count - 1; 419 while (p <= q) 420 { 421 m = p + (q - p)/2; 422 dxtrace(printk(".")); 423 if (dx_get_hash(m) > hash) 424 q = m - 1; 425 else 426 p = m + 1; 427 } 428 429 if (0) // linear search cross check 430 { 431 unsigned n = count - 1; 432 at = entries; 433 while (n--) 434 { 435 dxtrace(printk(",")); 436 if (dx_get_hash(++at) > hash) 437 { 438 at--; 439 break; 440 } 441 } 442 assert (at == p - 1); 443 } 444 445 at = p - 1; 446 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at))); 447 frame->bh = bh; 448 frame->entries = entries; 449 frame->at = at; 450 if (!indirect--) return frame; 451 if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err))) 452 goto fail2; 453 at = entries = ((struct dx_node *) bh->b_data)->entries; 454 if (dx_get_limit(entries) != dx_node_limit (dir)) { 455 ext3_warning(dir->i_sb, __func__, 456 "dx entry: limit != node limit"); 457 brelse(bh); 458 *err = ERR_BAD_DX_DIR; 459 goto fail2; 460 } 461 frame++; 462 frame->bh = NULL; 463 } 464fail2: 465 while (frame >= frame_in) { 466 brelse(frame->bh); 467 frame--; 468 } 469fail: 470 if (*err == ERR_BAD_DX_DIR) 471 ext3_warning(dir->i_sb, __func__, 472 "Corrupt dir inode %ld, running e2fsck is " 473 "recommended.", dir->i_ino); 474 return NULL; 475} 476 477static void dx_release (struct dx_frame *frames) 478{ 479 if (frames[0].bh == NULL) 480 return; 481 482 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels) 483 brelse(frames[1].bh); 484 brelse(frames[0].bh); 485} 486 487/* 488 * This function increments the frame pointer to search the next leaf 489 * block, and reads in the necessary intervening nodes if the search 490 * should be necessary. Whether or not the search is necessary is 491 * controlled by the hash parameter. If the hash value is even, then 492 * the search is only continued if the next block starts with that 493 * hash value. This is used if we are searching for a specific file. 494 * 495 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 496 * 497 * This function returns 1 if the caller should continue to search, 498 * or 0 if it should not. If there is an error reading one of the 499 * index blocks, it will a negative error code. 500 * 501 * If start_hash is non-null, it will be filled in with the starting 502 * hash of the next page. 503 */ 504static int ext3_htree_next_block(struct inode *dir, __u32 hash, 505 struct dx_frame *frame, 506 struct dx_frame *frames, 507 __u32 *start_hash) 508{ 509 struct dx_frame *p; 510 struct buffer_head *bh; 511 int err, num_frames = 0; 512 __u32 bhash; 513 514 p = frame; 515 /* 516 * Find the next leaf page by incrementing the frame pointer. 517 * If we run out of entries in the interior node, loop around and 518 * increment pointer in the parent node. When we break out of 519 * this loop, num_frames indicates the number of interior 520 * nodes need to be read. 521 */ 522 while (1) { 523 if (++(p->at) < p->entries + dx_get_count(p->entries)) 524 break; 525 if (p == frames) 526 return 0; 527 num_frames++; 528 p--; 529 } 530 531 /* 532 * If the hash is 1, then continue only if the next page has a 533 * continuation hash of any value. This is used for readdir 534 * handling. Otherwise, check to see if the hash matches the 535 * desired contiuation hash. If it doesn't, return since 536 * there's no point to read in the successive index pages. 537 */ 538 bhash = dx_get_hash(p->at); 539 if (start_hash) 540 *start_hash = bhash; 541 if ((hash & 1) == 0) { 542 if ((bhash & ~1) != hash) 543 return 0; 544 } 545 /* 546 * If the hash is HASH_NB_ALWAYS, we always go to the next 547 * block so no check is necessary 548 */ 549 while (num_frames--) { 550 if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at), 551 0, &err))) 552 return err; /* Failure */ 553 p++; 554 brelse (p->bh); 555 p->bh = bh; 556 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 557 } 558 return 1; 559} 560 561 562/* 563 * This function fills a red-black tree with information from a 564 * directory block. It returns the number directory entries loaded 565 * into the tree. If there is an error it is returned in err. 566 */ 567static int htree_dirblock_to_tree(struct file *dir_file, 568 struct inode *dir, int block, 569 struct dx_hash_info *hinfo, 570 __u32 start_hash, __u32 start_minor_hash) 571{ 572 struct buffer_head *bh; 573 struct ext3_dir_entry_2 *de, *top; 574 int err, count = 0; 575 576 dxtrace(printk("In htree dirblock_to_tree: block %d\n", block)); 577 if (!(bh = ext3_bread (NULL, dir, block, 0, &err))) 578 return err; 579 580 de = (struct ext3_dir_entry_2 *) bh->b_data; 581 top = (struct ext3_dir_entry_2 *) ((char *) de + 582 dir->i_sb->s_blocksize - 583 EXT3_DIR_REC_LEN(0)); 584 for (; de < top; de = ext3_next_entry(de)) { 585 if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh, 586 (block<<EXT3_BLOCK_SIZE_BITS(dir->i_sb)) 587 +((char *)de - bh->b_data))) { 588 /* On error, skip the f_pos to the next block. */ 589 dir_file->f_pos = (dir_file->f_pos | 590 (dir->i_sb->s_blocksize - 1)) + 1; 591 brelse (bh); 592 return count; 593 } 594 ext3fs_dirhash(de->name, de->name_len, hinfo); 595 if ((hinfo->hash < start_hash) || 596 ((hinfo->hash == start_hash) && 597 (hinfo->minor_hash < start_minor_hash))) 598 continue; 599 if (de->inode == 0) 600 continue; 601 if ((err = ext3_htree_store_dirent(dir_file, 602 hinfo->hash, hinfo->minor_hash, de)) != 0) { 603 brelse(bh); 604 return err; 605 } 606 count++; 607 } 608 brelse(bh); 609 return count; 610} 611 612 613/* 614 * This function fills a red-black tree with information from a 615 * directory. We start scanning the directory in hash order, starting 616 * at start_hash and start_minor_hash. 617 * 618 * This function returns the number of entries inserted into the tree, 619 * or a negative error code. 620 */ 621int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash, 622 __u32 start_minor_hash, __u32 *next_hash) 623{ 624 struct dx_hash_info hinfo; 625 struct ext3_dir_entry_2 *de; 626 struct dx_frame frames[2], *frame; 627 struct inode *dir; 628 int block, err; 629 int count = 0; 630 int ret; 631 __u32 hashval; 632 633 dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash, 634 start_minor_hash)); 635 dir = dir_file->f_path.dentry->d_inode; 636 if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) { 637 hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 638 if (hinfo.hash_version <= DX_HASH_TEA) 639 hinfo.hash_version += 640 EXT3_SB(dir->i_sb)->s_hash_unsigned; 641 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 642 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 643 start_hash, start_minor_hash); 644 *next_hash = ~0; 645 return count; 646 } 647 hinfo.hash = start_hash; 648 hinfo.minor_hash = 0; 649 frame = dx_probe(NULL, dir_file->f_path.dentry->d_inode, &hinfo, frames, &err); 650 if (!frame) 651 return err; 652 653 /* Add '.' and '..' from the htree header */ 654 if (!start_hash && !start_minor_hash) { 655 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 656 if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0) 657 goto errout; 658 count++; 659 } 660 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 661 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 662 de = ext3_next_entry(de); 663 if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0) 664 goto errout; 665 count++; 666 } 667 668 while (1) { 669 block = dx_get_block(frame->at); 670 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 671 start_hash, start_minor_hash); 672 if (ret < 0) { 673 err = ret; 674 goto errout; 675 } 676 count += ret; 677 hashval = ~0; 678 ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS, 679 frame, frames, &hashval); 680 *next_hash = hashval; 681 if (ret < 0) { 682 err = ret; 683 goto errout; 684 } 685 /* 686 * Stop if: (a) there are no more entries, or 687 * (b) we have inserted at least one entry and the 688 * next hash value is not a continuation 689 */ 690 if ((ret == 0) || 691 (count && ((hashval & 1) == 0))) 692 break; 693 } 694 dx_release(frames); 695 dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n", 696 count, *next_hash)); 697 return count; 698errout: 699 dx_release(frames); 700 return (err); 701} 702 703 704/* 705 * Directory block splitting, compacting 706 */ 707 708/* 709 * Create map of hash values, offsets, and sizes, stored at end of block. 710 * Returns number of entries mapped. 711 */ 712static int dx_make_map(struct ext3_dir_entry_2 *de, unsigned blocksize, 713 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail) 714{ 715 int count = 0; 716 char *base = (char *) de; 717 struct dx_hash_info h = *hinfo; 718 719 while ((char *) de < base + blocksize) 720 { 721 if (de->name_len && de->inode) { 722 ext3fs_dirhash(de->name, de->name_len, &h); 723 map_tail--; 724 map_tail->hash = h.hash; 725 map_tail->offs = (u16) ((char *) de - base); 726 map_tail->size = le16_to_cpu(de->rec_len); 727 count++; 728 cond_resched(); 729 } 730 /* XXX: do we need to check rec_len == 0 case? -Chris */ 731 de = ext3_next_entry(de); 732 } 733 return count; 734} 735 736/* Sort map by hash value */ 737static void dx_sort_map (struct dx_map_entry *map, unsigned count) 738{ 739 struct dx_map_entry *p, *q, *top = map + count - 1; 740 int more; 741 /* Combsort until bubble sort doesn't suck */ 742 while (count > 2) 743 { 744 count = count*10/13; 745 if (count - 9 < 2) /* 9, 10 -> 11 */ 746 count = 11; 747 for (p = top, q = p - count; q >= map; p--, q--) 748 if (p->hash < q->hash) 749 swap(*p, *q); 750 } 751 /* Garden variety bubble sort */ 752 do { 753 more = 0; 754 q = top; 755 while (q-- > map) 756 { 757 if (q[1].hash >= q[0].hash) 758 continue; 759 swap(*(q+1), *q); 760 more = 1; 761 } 762 } while(more); 763} 764 765static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block) 766{ 767 struct dx_entry *entries = frame->entries; 768 struct dx_entry *old = frame->at, *new = old + 1; 769 int count = dx_get_count(entries); 770 771 assert(count < dx_get_limit(entries)); 772 assert(old < entries + count); 773 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 774 dx_set_hash(new, hash); 775 dx_set_block(new, block); 776 dx_set_count(entries, count + 1); 777} 778 779static void ext3_update_dx_flag(struct inode *inode) 780{ 781 if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb, 782 EXT3_FEATURE_COMPAT_DIR_INDEX)) 783 EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL; 784} 785 786/* 787 * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure. 788 * 789 * `len <= EXT3_NAME_LEN' is guaranteed by caller. 790 * `de != NULL' is guaranteed by caller. 791 */ 792static inline int ext3_match (int len, const char * const name, 793 struct ext3_dir_entry_2 * de) 794{ 795 if (len != de->name_len) 796 return 0; 797 if (!de->inode) 798 return 0; 799 return !memcmp(name, de->name, len); 800} 801 802/* 803 * Returns 0 if not found, -1 on failure, and 1 on success 804 */ 805static inline int search_dirblock(struct buffer_head * bh, 806 struct inode *dir, 807 struct qstr *child, 808 unsigned long offset, 809 struct ext3_dir_entry_2 ** res_dir) 810{ 811 struct ext3_dir_entry_2 * de; 812 char * dlimit; 813 int de_len; 814 const char *name = child->name; 815 int namelen = child->len; 816 817 de = (struct ext3_dir_entry_2 *) bh->b_data; 818 dlimit = bh->b_data + dir->i_sb->s_blocksize; 819 while ((char *) de < dlimit) { 820 /* this code is executed quadratically often */ 821 /* do minimal checking `by hand' */ 822 823 if ((char *) de + namelen <= dlimit && 824 ext3_match (namelen, name, de)) { 825 /* found a match - just to be sure, do a full check */ 826 if (!ext3_check_dir_entry("ext3_find_entry", 827 dir, de, bh, offset)) 828 return -1; 829 *res_dir = de; 830 return 1; 831 } 832 /* prevent looping on a bad block */ 833 de_len = ext3_rec_len_from_disk(de->rec_len); 834 if (de_len <= 0) 835 return -1; 836 offset += de_len; 837 de = (struct ext3_dir_entry_2 *) ((char *) de + de_len); 838 } 839 return 0; 840} 841 842 843/* 844 * ext3_find_entry() 845 * 846 * finds an entry in the specified directory with the wanted name. It 847 * returns the cache buffer in which the entry was found, and the entry 848 * itself (as a parameter - res_dir). It does NOT read the inode of the 849 * entry - you'll have to do that yourself if you want to. 850 * 851 * The returned buffer_head has ->b_count elevated. The caller is expected 852 * to brelse() it when appropriate. 853 */ 854static struct buffer_head *ext3_find_entry(struct inode *dir, 855 struct qstr *entry, 856 struct ext3_dir_entry_2 **res_dir) 857{ 858 struct super_block * sb; 859 struct buffer_head * bh_use[NAMEI_RA_SIZE]; 860 struct buffer_head * bh, *ret = NULL; 861 unsigned long start, block, b; 862 const u8 *name = entry->name; 863 int ra_max = 0; /* Number of bh's in the readahead 864 buffer, bh_use[] */ 865 int ra_ptr = 0; /* Current index into readahead 866 buffer */ 867 int num = 0; 868 int nblocks, i, err; 869 int namelen; 870 871 *res_dir = NULL; 872 sb = dir->i_sb; 873 namelen = entry->len; 874 if (namelen > EXT3_NAME_LEN) 875 return NULL; 876 if ((namelen <= 2) && (name[0] == '.') && 877 (name[1] == '.' || name[1] == 0)) { 878 /* 879 * "." or ".." will only be in the first block 880 * NFS may look up ".."; "." should be handled by the VFS 881 */ 882 block = start = 0; 883 nblocks = 1; 884 goto restart; 885 } 886 if (is_dx(dir)) { 887 bh = ext3_dx_find_entry(dir, entry, res_dir, &err); 888 /* 889 * On success, or if the error was file not found, 890 * return. Otherwise, fall back to doing a search the 891 * old fashioned way. 892 */ 893 if (bh || (err != ERR_BAD_DX_DIR)) 894 return bh; 895 dxtrace(printk("ext3_find_entry: dx failed, falling back\n")); 896 } 897 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); 898 start = EXT3_I(dir)->i_dir_start_lookup; 899 if (start >= nblocks) 900 start = 0; 901 block = start; 902restart: 903 do { 904 /* 905 * We deal with the read-ahead logic here. 906 */ 907 if (ra_ptr >= ra_max) { 908 /* Refill the readahead buffer */ 909 ra_ptr = 0; 910 b = block; 911 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) { 912 /* 913 * Terminate if we reach the end of the 914 * directory and must wrap, or if our 915 * search has finished at this block. 916 */ 917 if (b >= nblocks || (num && block == start)) { 918 bh_use[ra_max] = NULL; 919 break; 920 } 921 num++; 922 bh = ext3_getblk(NULL, dir, b++, 0, &err); 923 bh_use[ra_max] = bh; 924 if (bh) 925 ll_rw_block(READ | REQ_META | REQ_PRIO, 926 1, &bh); 927 } 928 } 929 if ((bh = bh_use[ra_ptr++]) == NULL) 930 goto next; 931 wait_on_buffer(bh); 932 if (!buffer_uptodate(bh)) { 933 /* read error, skip block & hope for the best */ 934 ext3_error(sb, __func__, "reading directory #%lu " 935 "offset %lu", dir->i_ino, block); 936 brelse(bh); 937 goto next; 938 } 939 i = search_dirblock(bh, dir, entry, 940 block << EXT3_BLOCK_SIZE_BITS(sb), res_dir); 941 if (i == 1) { 942 EXT3_I(dir)->i_dir_start_lookup = block; 943 ret = bh; 944 goto cleanup_and_exit; 945 } else { 946 brelse(bh); 947 if (i < 0) 948 goto cleanup_and_exit; 949 } 950 next: 951 if (++block >= nblocks) 952 block = 0; 953 } while (block != start); 954 955 /* 956 * If the directory has grown while we were searching, then 957 * search the last part of the directory before giving up. 958 */ 959 block = nblocks; 960 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); 961 if (block < nblocks) { 962 start = 0; 963 goto restart; 964 } 965 966cleanup_and_exit: 967 /* Clean up the read-ahead blocks */ 968 for (; ra_ptr < ra_max; ra_ptr++) 969 brelse (bh_use[ra_ptr]); 970 return ret; 971} 972 973static struct buffer_head * ext3_dx_find_entry(struct inode *dir, 974 struct qstr *entry, struct ext3_dir_entry_2 **res_dir, 975 int *err) 976{ 977 struct super_block *sb = dir->i_sb; 978 struct dx_hash_info hinfo; 979 struct dx_frame frames[2], *frame; 980 struct buffer_head *bh; 981 unsigned long block; 982 int retval; 983 984 if (!(frame = dx_probe(entry, dir, &hinfo, frames, err))) 985 return NULL; 986 do { 987 block = dx_get_block(frame->at); 988 if (!(bh = ext3_bread (NULL,dir, block, 0, err))) 989 goto errout; 990 991 retval = search_dirblock(bh, dir, entry, 992 block << EXT3_BLOCK_SIZE_BITS(sb), 993 res_dir); 994 if (retval == 1) { 995 dx_release(frames); 996 return bh; 997 } 998 brelse(bh); 999 if (retval == -1) { 1000 *err = ERR_BAD_DX_DIR; 1001 goto errout; 1002 } 1003 1004 /* Check to see if we should continue to search */ 1005 retval = ext3_htree_next_block(dir, hinfo.hash, frame, 1006 frames, NULL); 1007 if (retval < 0) { 1008 ext3_warning(sb, __func__, 1009 "error reading index page in directory #%lu", 1010 dir->i_ino); 1011 *err = retval; 1012 goto errout; 1013 } 1014 } while (retval == 1); 1015 1016 *err = -ENOENT; 1017errout: 1018 dxtrace(printk("%s not found\n", entry->name)); 1019 dx_release (frames); 1020 return NULL; 1021} 1022 1023static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) 1024{ 1025 struct inode * inode; 1026 struct ext3_dir_entry_2 * de; 1027 struct buffer_head * bh; 1028 1029 if (dentry->d_name.len > EXT3_NAME_LEN) 1030 return ERR_PTR(-ENAMETOOLONG); 1031 1032 bh = ext3_find_entry(dir, &dentry->d_name, &de); 1033 inode = NULL; 1034 if (bh) { 1035 unsigned long ino = le32_to_cpu(de->inode); 1036 brelse (bh); 1037 if (!ext3_valid_inum(dir->i_sb, ino)) { 1038 ext3_error(dir->i_sb, "ext3_lookup", 1039 "bad inode number: %lu", ino); 1040 return ERR_PTR(-EIO); 1041 } 1042 inode = ext3_iget(dir->i_sb, ino); 1043 if (inode == ERR_PTR(-ESTALE)) { 1044 ext3_error(dir->i_sb, __func__, 1045 "deleted inode referenced: %lu", 1046 ino); 1047 return ERR_PTR(-EIO); 1048 } 1049 } 1050 return d_splice_alias(inode, dentry); 1051} 1052 1053 1054struct dentry *ext3_get_parent(struct dentry *child) 1055{ 1056 unsigned long ino; 1057 struct qstr dotdot = {.name = "..", .len = 2}; 1058 struct ext3_dir_entry_2 * de; 1059 struct buffer_head *bh; 1060 1061 bh = ext3_find_entry(child->d_inode, &dotdot, &de); 1062 if (!bh) 1063 return ERR_PTR(-ENOENT); 1064 ino = le32_to_cpu(de->inode); 1065 brelse(bh); 1066 1067 if (!ext3_valid_inum(child->d_inode->i_sb, ino)) { 1068 ext3_error(child->d_inode->i_sb, "ext3_get_parent", 1069 "bad inode number: %lu", ino); 1070 return ERR_PTR(-EIO); 1071 } 1072 1073 return d_obtain_alias(ext3_iget(child->d_inode->i_sb, ino)); 1074} 1075 1076#define S_SHIFT 12 1077static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = { 1078 [S_IFREG >> S_SHIFT] = EXT3_FT_REG_FILE, 1079 [S_IFDIR >> S_SHIFT] = EXT3_FT_DIR, 1080 [S_IFCHR >> S_SHIFT] = EXT3_FT_CHRDEV, 1081 [S_IFBLK >> S_SHIFT] = EXT3_FT_BLKDEV, 1082 [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO, 1083 [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK, 1084 [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK, 1085}; 1086 1087static inline void ext3_set_de_type(struct super_block *sb, 1088 struct ext3_dir_entry_2 *de, 1089 umode_t mode) { 1090 if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE)) 1091 de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; 1092} 1093 1094/* 1095 * Move count entries from end of map between two memory locations. 1096 * Returns pointer to last entry moved. 1097 */ 1098static struct ext3_dir_entry_2 * 1099dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) 1100{ 1101 unsigned rec_len = 0; 1102 1103 while (count--) { 1104 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs); 1105 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1106 memcpy (to, de, rec_len); 1107 ((struct ext3_dir_entry_2 *) to)->rec_len = 1108 ext3_rec_len_to_disk(rec_len); 1109 de->inode = 0; 1110 map++; 1111 to += rec_len; 1112 } 1113 return (struct ext3_dir_entry_2 *) (to - rec_len); 1114} 1115 1116/* 1117 * Compact each dir entry in the range to the minimal rec_len. 1118 * Returns pointer to last entry in range. 1119 */ 1120static struct ext3_dir_entry_2 *dx_pack_dirents(char *base, unsigned blocksize) 1121{ 1122 struct ext3_dir_entry_2 *next, *to, *prev; 1123 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *)base; 1124 unsigned rec_len = 0; 1125 1126 prev = to = de; 1127 while ((char *)de < base + blocksize) { 1128 next = ext3_next_entry(de); 1129 if (de->inode && de->name_len) { 1130 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1131 if (de > to) 1132 memmove(to, de, rec_len); 1133 to->rec_len = ext3_rec_len_to_disk(rec_len); 1134 prev = to; 1135 to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len); 1136 } 1137 de = next; 1138 } 1139 return prev; 1140} 1141 1142/* 1143 * Split a full leaf block to make room for a new dir entry. 1144 * Allocate a new block, and move entries so that they are approx. equally full. 1145 * Returns pointer to de in block into which the new entry will be inserted. 1146 */ 1147static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1148 struct buffer_head **bh,struct dx_frame *frame, 1149 struct dx_hash_info *hinfo, int *error) 1150{ 1151 unsigned blocksize = dir->i_sb->s_blocksize; 1152 unsigned count, continued; 1153 struct buffer_head *bh2; 1154 u32 newblock; 1155 u32 hash2; 1156 struct dx_map_entry *map; 1157 char *data1 = (*bh)->b_data, *data2; 1158 unsigned split, move, size; 1159 struct ext3_dir_entry_2 *de = NULL, *de2; 1160 int err = 0, i; 1161 1162 bh2 = ext3_append (handle, dir, &newblock, &err); 1163 if (!(bh2)) { 1164 brelse(*bh); 1165 *bh = NULL; 1166 goto errout; 1167 } 1168 1169 BUFFER_TRACE(*bh, "get_write_access"); 1170 err = ext3_journal_get_write_access(handle, *bh); 1171 if (err) 1172 goto journal_error; 1173 1174 BUFFER_TRACE(frame->bh, "get_write_access"); 1175 err = ext3_journal_get_write_access(handle, frame->bh); 1176 if (err) 1177 goto journal_error; 1178 1179 data2 = bh2->b_data; 1180 1181 /* create map in the end of data2 block */ 1182 map = (struct dx_map_entry *) (data2 + blocksize); 1183 count = dx_make_map ((struct ext3_dir_entry_2 *) data1, 1184 blocksize, hinfo, map); 1185 map -= count; 1186 dx_sort_map (map, count); 1187 /* Split the existing block in the middle, size-wise */ 1188 size = 0; 1189 move = 0; 1190 for (i = count-1; i >= 0; i--) { 1191 /* is more than half of this entry in 2nd half of the block? */ 1192 if (size + map[i].size/2 > blocksize/2) 1193 break; 1194 size += map[i].size; 1195 move++; 1196 } 1197 /* map index at which we will split */ 1198 split = count - move; 1199 hash2 = map[split].hash; 1200 continued = hash2 == map[split - 1].hash; 1201 dxtrace(printk("Split block %i at %x, %i/%i\n", 1202 dx_get_block(frame->at), hash2, split, count-split)); 1203 1204 /* Fancy dance to stay within two buffers */ 1205 de2 = dx_move_dirents(data1, data2, map + split, count - split); 1206 de = dx_pack_dirents(data1,blocksize); 1207 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de); 1208 de2->rec_len = ext3_rec_len_to_disk(data2 + blocksize - (char *) de2); 1209 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1)); 1210 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1)); 1211 1212 /* Which block gets the new entry? */ 1213 if (hinfo->hash >= hash2) 1214 { 1215 swap(*bh, bh2); 1216 de = de2; 1217 } 1218 dx_insert_block (frame, hash2 + continued, newblock); 1219 err = ext3_journal_dirty_metadata (handle, bh2); 1220 if (err) 1221 goto journal_error; 1222 err = ext3_journal_dirty_metadata (handle, frame->bh); 1223 if (err) 1224 goto journal_error; 1225 brelse (bh2); 1226 dxtrace(dx_show_index ("frame", frame->entries)); 1227 return de; 1228 1229journal_error: 1230 brelse(*bh); 1231 brelse(bh2); 1232 *bh = NULL; 1233 ext3_std_error(dir->i_sb, err); 1234errout: 1235 *error = err; 1236 return NULL; 1237} 1238 1239 1240/* 1241 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1242 * it points to a directory entry which is guaranteed to be large 1243 * enough for new directory entry. If de is NULL, then 1244 * add_dirent_to_buf will attempt search the directory block for 1245 * space. It will return -ENOSPC if no space is available, and -EIO 1246 * and -EEXIST if directory entry already exists. 1247 * 1248 * NOTE! bh is NOT released in the case where ENOSPC is returned. In 1249 * all other cases bh is released. 1250 */ 1251static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, 1252 struct inode *inode, struct ext3_dir_entry_2 *de, 1253 struct buffer_head * bh) 1254{ 1255 struct inode *dir = dentry->d_parent->d_inode; 1256 const char *name = dentry->d_name.name; 1257 int namelen = dentry->d_name.len; 1258 unsigned long offset = 0; 1259 unsigned short reclen; 1260 int nlen, rlen, err; 1261 char *top; 1262 1263 reclen = EXT3_DIR_REC_LEN(namelen); 1264 if (!de) { 1265 de = (struct ext3_dir_entry_2 *)bh->b_data; 1266 top = bh->b_data + dir->i_sb->s_blocksize - reclen; 1267 while ((char *) de <= top) { 1268 if (!ext3_check_dir_entry("ext3_add_entry", dir, de, 1269 bh, offset)) { 1270 brelse (bh); 1271 return -EIO; 1272 } 1273 if (ext3_match (namelen, name, de)) { 1274 brelse (bh); 1275 return -EEXIST; 1276 } 1277 nlen = EXT3_DIR_REC_LEN(de->name_len); 1278 rlen = ext3_rec_len_from_disk(de->rec_len); 1279 if ((de->inode? rlen - nlen: rlen) >= reclen) 1280 break; 1281 de = (struct ext3_dir_entry_2 *)((char *)de + rlen); 1282 offset += rlen; 1283 } 1284 if ((char *) de > top) 1285 return -ENOSPC; 1286 } 1287 BUFFER_TRACE(bh, "get_write_access"); 1288 err = ext3_journal_get_write_access(handle, bh); 1289 if (err) { 1290 ext3_std_error(dir->i_sb, err); 1291 brelse(bh); 1292 return err; 1293 } 1294 1295 /* By now the buffer is marked for journaling */ 1296 nlen = EXT3_DIR_REC_LEN(de->name_len); 1297 rlen = ext3_rec_len_from_disk(de->rec_len); 1298 if (de->inode) { 1299 struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen); 1300 de1->rec_len = ext3_rec_len_to_disk(rlen - nlen); 1301 de->rec_len = ext3_rec_len_to_disk(nlen); 1302 de = de1; 1303 } 1304 de->file_type = EXT3_FT_UNKNOWN; 1305 if (inode) { 1306 de->inode = cpu_to_le32(inode->i_ino); 1307 ext3_set_de_type(dir->i_sb, de, inode->i_mode); 1308 } else 1309 de->inode = 0; 1310 de->name_len = namelen; 1311 memcpy (de->name, name, namelen); 1312 /* 1313 * XXX shouldn't update any times until successful 1314 * completion of syscall, but too many callers depend 1315 * on this. 1316 * 1317 * XXX similarly, too many callers depend on 1318 * ext3_new_inode() setting the times, but error 1319 * recovery deletes the inode, so the worst that can 1320 * happen is that the times are slightly out of date 1321 * and/or different from the directory change time. 1322 */ 1323 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; 1324 ext3_update_dx_flag(dir); 1325 dir->i_version++; 1326 ext3_mark_inode_dirty(handle, dir); 1327 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1328 err = ext3_journal_dirty_metadata(handle, bh); 1329 if (err) 1330 ext3_std_error(dir->i_sb, err); 1331 brelse(bh); 1332 return 0; 1333} 1334 1335/* 1336 * This converts a one block unindexed directory to a 3 block indexed 1337 * directory, and adds the dentry to the indexed directory. 1338 */ 1339static int make_indexed_dir(handle_t *handle, struct dentry *dentry, 1340 struct inode *inode, struct buffer_head *bh) 1341{ 1342 struct inode *dir = dentry->d_parent->d_inode; 1343 const char *name = dentry->d_name.name; 1344 int namelen = dentry->d_name.len; 1345 struct buffer_head *bh2; 1346 struct dx_root *root; 1347 struct dx_frame frames[2], *frame; 1348 struct dx_entry *entries; 1349 struct ext3_dir_entry_2 *de, *de2; 1350 char *data1, *top; 1351 unsigned len; 1352 int retval; 1353 unsigned blocksize; 1354 struct dx_hash_info hinfo; 1355 u32 block; 1356 struct fake_dirent *fde; 1357 1358 blocksize = dir->i_sb->s_blocksize; 1359 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); 1360 retval = ext3_journal_get_write_access(handle, bh); 1361 if (retval) { 1362 ext3_std_error(dir->i_sb, retval); 1363 brelse(bh); 1364 return retval; 1365 } 1366 root = (struct dx_root *) bh->b_data; 1367 1368 /* The 0th block becomes the root, move the dirents out */ 1369 fde = &root->dotdot; 1370 de = (struct ext3_dir_entry_2 *)((char *)fde + 1371 ext3_rec_len_from_disk(fde->rec_len)); 1372 if ((char *) de >= (((char *) root) + blocksize)) { 1373 ext3_error(dir->i_sb, __func__, 1374 "invalid rec_len for '..' in inode %lu", 1375 dir->i_ino); 1376 brelse(bh); 1377 return -EIO; 1378 } 1379 len = ((char *) root) + blocksize - (char *) de; 1380 1381 bh2 = ext3_append (handle, dir, &block, &retval); 1382 if (!(bh2)) { 1383 brelse(bh); 1384 return retval; 1385 } 1386 EXT3_I(dir)->i_flags |= EXT3_INDEX_FL; 1387 data1 = bh2->b_data; 1388 1389 memcpy (data1, de, len); 1390 de = (struct ext3_dir_entry_2 *) data1; 1391 top = data1 + len; 1392 while ((char *)(de2 = ext3_next_entry(de)) < top) 1393 de = de2; 1394 de->rec_len = ext3_rec_len_to_disk(data1 + blocksize - (char *) de); 1395 /* Initialize the root; the dot dirents already exist */ 1396 de = (struct ext3_dir_entry_2 *) (&root->dotdot); 1397 de->rec_len = ext3_rec_len_to_disk(blocksize - EXT3_DIR_REC_LEN(2)); 1398 memset (&root->info, 0, sizeof(root->info)); 1399 root->info.info_length = sizeof(root->info); 1400 root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 1401 entries = root->entries; 1402 dx_set_block (entries, 1); 1403 dx_set_count (entries, 1); 1404 dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info))); 1405 1406 /* Initialize as for dx_probe */ 1407 hinfo.hash_version = root->info.hash_version; 1408 if (hinfo.hash_version <= DX_HASH_TEA) 1409 hinfo.hash_version += EXT3_SB(dir->i_sb)->s_hash_unsigned; 1410 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 1411 ext3fs_dirhash(name, namelen, &hinfo); 1412 frame = frames; 1413 frame->entries = entries; 1414 frame->at = entries; 1415 frame->bh = bh; 1416 bh = bh2; 1417 /* 1418 * Mark buffers dirty here so that if do_split() fails we write a 1419 * consistent set of buffers to disk. 1420 */ 1421 ext3_journal_dirty_metadata(handle, frame->bh); 1422 ext3_journal_dirty_metadata(handle, bh); 1423 de = do_split(handle,dir, &bh, frame, &hinfo, &retval); 1424 if (!de) { 1425 ext3_mark_inode_dirty(handle, dir); 1426 dx_release(frames); 1427 return retval; 1428 } 1429 dx_release(frames); 1430 1431 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1432} 1433 1434/* 1435 * ext3_add_entry() 1436 * 1437 * adds a file entry to the specified directory, using the same 1438 * semantics as ext3_find_entry(). It returns NULL if it failed. 1439 * 1440 * NOTE!! The inode part of 'de' is left at 0 - which means you 1441 * may not sleep between calling this and putting something into 1442 * the entry, as someone else might have used it while you slept. 1443 */ 1444static int ext3_add_entry (handle_t *handle, struct dentry *dentry, 1445 struct inode *inode) 1446{ 1447 struct inode *dir = dentry->d_parent->d_inode; 1448 struct buffer_head * bh; 1449 struct ext3_dir_entry_2 *de; 1450 struct super_block * sb; 1451 int retval; 1452 int dx_fallback=0; 1453 unsigned blocksize; 1454 u32 block, blocks; 1455 1456 sb = dir->i_sb; 1457 blocksize = sb->s_blocksize; 1458 if (!dentry->d_name.len) 1459 return -EINVAL; 1460 if (is_dx(dir)) { 1461 retval = ext3_dx_add_entry(handle, dentry, inode); 1462 if (!retval || (retval != ERR_BAD_DX_DIR)) 1463 return retval; 1464 EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL; 1465 dx_fallback++; 1466 ext3_mark_inode_dirty(handle, dir); 1467 } 1468 blocks = dir->i_size >> sb->s_blocksize_bits; 1469 for (block = 0; block < blocks; block++) { 1470 bh = ext3_bread(handle, dir, block, 0, &retval); 1471 if(!bh) 1472 return retval; 1473 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1474 if (retval != -ENOSPC) 1475 return retval; 1476 1477 if (blocks == 1 && !dx_fallback && 1478 EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) 1479 return make_indexed_dir(handle, dentry, inode, bh); 1480 brelse(bh); 1481 } 1482 bh = ext3_append(handle, dir, &block, &retval); 1483 if (!bh) 1484 return retval; 1485 de = (struct ext3_dir_entry_2 *) bh->b_data; 1486 de->inode = 0; 1487 de->rec_len = ext3_rec_len_to_disk(blocksize); 1488 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1489} 1490 1491/* 1492 * Returns 0 for success, or a negative error value 1493 */ 1494static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, 1495 struct inode *inode) 1496{ 1497 struct dx_frame frames[2], *frame; 1498 struct dx_entry *entries, *at; 1499 struct dx_hash_info hinfo; 1500 struct buffer_head * bh; 1501 struct inode *dir = dentry->d_parent->d_inode; 1502 struct super_block * sb = dir->i_sb; 1503 struct ext3_dir_entry_2 *de; 1504 int err; 1505 1506 frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err); 1507 if (!frame) 1508 return err; 1509 entries = frame->entries; 1510 at = frame->at; 1511 1512 if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err))) 1513 goto cleanup; 1514 1515 BUFFER_TRACE(bh, "get_write_access"); 1516 err = ext3_journal_get_write_access(handle, bh); 1517 if (err) 1518 goto journal_error; 1519 1520 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1521 if (err != -ENOSPC) { 1522 bh = NULL; 1523 goto cleanup; 1524 } 1525 1526 /* Block full, should compress but for now just split */ 1527 dxtrace(printk("using %u of %u node entries\n", 1528 dx_get_count(entries), dx_get_limit(entries))); 1529 /* Need to split index? */ 1530 if (dx_get_count(entries) == dx_get_limit(entries)) { 1531 u32 newblock; 1532 unsigned icount = dx_get_count(entries); 1533 int levels = frame - frames; 1534 struct dx_entry *entries2; 1535 struct dx_node *node2; 1536 struct buffer_head *bh2; 1537 1538 if (levels && (dx_get_count(frames->entries) == 1539 dx_get_limit(frames->entries))) { 1540 ext3_warning(sb, __func__, 1541 "Directory index full!"); 1542 err = -ENOSPC; 1543 goto cleanup; 1544 } 1545 bh2 = ext3_append (handle, dir, &newblock, &err); 1546 if (!(bh2)) 1547 goto cleanup; 1548 node2 = (struct dx_node *)(bh2->b_data); 1549 entries2 = node2->entries; 1550 memset(&node2->fake, 0, sizeof(struct fake_dirent)); 1551 node2->fake.rec_len = ext3_rec_len_to_disk(sb->s_blocksize); 1552 BUFFER_TRACE(frame->bh, "get_write_access"); 1553 err = ext3_journal_get_write_access(handle, frame->bh); 1554 if (err) 1555 goto journal_error; 1556 if (levels) { 1557 unsigned icount1 = icount/2, icount2 = icount - icount1; 1558 unsigned hash2 = dx_get_hash(entries + icount1); 1559 dxtrace(printk("Split index %i/%i\n", icount1, icount2)); 1560 1561 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 1562 err = ext3_journal_get_write_access(handle, 1563 frames[0].bh); 1564 if (err) 1565 goto journal_error; 1566 1567 memcpy ((char *) entries2, (char *) (entries + icount1), 1568 icount2 * sizeof(struct dx_entry)); 1569 dx_set_count (entries, icount1); 1570 dx_set_count (entries2, icount2); 1571 dx_set_limit (entries2, dx_node_limit(dir)); 1572 1573 /* Which index block gets the new entry? */ 1574 if (at - entries >= icount1) { 1575 frame->at = at = at - entries - icount1 + entries2; 1576 frame->entries = entries = entries2; 1577 swap(frame->bh, bh2); 1578 } 1579 dx_insert_block (frames + 0, hash2, newblock); 1580 dxtrace(dx_show_index ("node", frames[1].entries)); 1581 dxtrace(dx_show_index ("node", 1582 ((struct dx_node *) bh2->b_data)->entries)); 1583 err = ext3_journal_dirty_metadata(handle, bh2); 1584 if (err) 1585 goto journal_error; 1586 brelse (bh2); 1587 } else { 1588 dxtrace(printk("Creating second level index...\n")); 1589 memcpy((char *) entries2, (char *) entries, 1590 icount * sizeof(struct dx_entry)); 1591 dx_set_limit(entries2, dx_node_limit(dir)); 1592 1593 /* Set up root */ 1594 dx_set_count(entries, 1); 1595 dx_set_block(entries + 0, newblock); 1596 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1; 1597 1598 /* Add new access path frame */ 1599 frame = frames + 1; 1600 frame->at = at = at - entries + entries2; 1601 frame->entries = entries = entries2; 1602 frame->bh = bh2; 1603 err = ext3_journal_get_write_access(handle, 1604 frame->bh); 1605 if (err) 1606 goto journal_error; 1607 } 1608 err = ext3_journal_dirty_metadata(handle, frames[0].bh); 1609 if (err) 1610 goto journal_error; 1611 } 1612 de = do_split(handle, dir, &bh, frame, &hinfo, &err); 1613 if (!de) 1614 goto cleanup; 1615 err = add_dirent_to_buf(handle, dentry, inode, de, bh); 1616 bh = NULL; 1617 goto cleanup; 1618 1619journal_error: 1620 ext3_std_error(dir->i_sb, err); 1621cleanup: 1622 if (bh) 1623 brelse(bh); 1624 dx_release(frames); 1625 return err; 1626} 1627 1628/* 1629 * ext3_delete_entry deletes a directory entry by merging it with the 1630 * previous entry 1631 */ 1632static int ext3_delete_entry (handle_t *handle, 1633 struct inode * dir, 1634 struct ext3_dir_entry_2 * de_del, 1635 struct buffer_head * bh) 1636{ 1637 struct ext3_dir_entry_2 * de, * pde; 1638 int i; 1639 1640 i = 0; 1641 pde = NULL; 1642 de = (struct ext3_dir_entry_2 *) bh->b_data; 1643 while (i < bh->b_size) { 1644 if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i)) 1645 return -EIO; 1646 if (de == de_del) { 1647 int err; 1648 1649 BUFFER_TRACE(bh, "get_write_access"); 1650 err = ext3_journal_get_write_access(handle, bh); 1651 if (err) 1652 goto journal_error; 1653 1654 if (pde) 1655 pde->rec_len = ext3_rec_len_to_disk( 1656 ext3_rec_len_from_disk(pde->rec_len) + 1657 ext3_rec_len_from_disk(de->rec_len)); 1658 else 1659 de->inode = 0; 1660 dir->i_version++; 1661 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1662 err = ext3_journal_dirty_metadata(handle, bh); 1663 if (err) { 1664journal_error: 1665 ext3_std_error(dir->i_sb, err); 1666 return err; 1667 } 1668 return 0; 1669 } 1670 i += ext3_rec_len_from_disk(de->rec_len); 1671 pde = de; 1672 de = ext3_next_entry(de); 1673 } 1674 return -ENOENT; 1675} 1676 1677static int ext3_add_nondir(handle_t *handle, 1678 struct dentry *dentry, struct inode *inode) 1679{ 1680 int err = ext3_add_entry(handle, dentry, inode); 1681 if (!err) { 1682 ext3_mark_inode_dirty(handle, inode); 1683 d_instantiate(dentry, inode); 1684 unlock_new_inode(inode); 1685 return 0; 1686 } 1687 drop_nlink(inode); 1688 unlock_new_inode(inode); 1689 iput(inode); 1690 return err; 1691} 1692 1693/* 1694 * By the time this is called, we already have created 1695 * the directory cache entry for the new file, but it 1696 * is so far negative - it has no inode. 1697 * 1698 * If the create succeeds, we fill in the inode information 1699 * with d_instantiate(). 1700 */ 1701static int ext3_create (struct inode * dir, struct dentry * dentry, int mode, 1702 struct nameidata *nd) 1703{ 1704 handle_t *handle; 1705 struct inode * inode; 1706 int err, retries = 0; 1707 1708 dquot_initialize(dir); 1709 1710retry: 1711 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1712 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1713 EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb)); 1714 if (IS_ERR(handle)) 1715 return PTR_ERR(handle); 1716 1717 if (IS_DIRSYNC(dir)) 1718 handle->h_sync = 1; 1719 1720 inode = ext3_new_inode (handle, dir, &dentry->d_name, mode); 1721 err = PTR_ERR(inode); 1722 if (!IS_ERR(inode)) { 1723 inode->i_op = &ext3_file_inode_operations; 1724 inode->i_fop = &ext3_file_operations; 1725 ext3_set_aops(inode); 1726 err = ext3_add_nondir(handle, dentry, inode); 1727 } 1728 ext3_journal_stop(handle); 1729 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1730 goto retry; 1731 return err; 1732} 1733 1734static int ext3_mknod (struct inode * dir, struct dentry *dentry, 1735 int mode, dev_t rdev) 1736{ 1737 handle_t *handle; 1738 struct inode *inode; 1739 int err, retries = 0; 1740 1741 if (!new_valid_dev(rdev)) 1742 return -EINVAL; 1743 1744 dquot_initialize(dir); 1745 1746retry: 1747 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1748 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1749 EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb)); 1750 if (IS_ERR(handle)) 1751 return PTR_ERR(handle); 1752 1753 if (IS_DIRSYNC(dir)) 1754 handle->h_sync = 1; 1755 1756 inode = ext3_new_inode (handle, dir, &dentry->d_name, mode); 1757 err = PTR_ERR(inode); 1758 if (!IS_ERR(inode)) { 1759 init_special_inode(inode, inode->i_mode, rdev); 1760#ifdef CONFIG_EXT3_FS_XATTR 1761 inode->i_op = &ext3_special_inode_operations; 1762#endif 1763 err = ext3_add_nondir(handle, dentry, inode); 1764 } 1765 ext3_journal_stop(handle); 1766 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1767 goto retry; 1768 return err; 1769} 1770 1771static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode) 1772{ 1773 handle_t *handle; 1774 struct inode * inode; 1775 struct buffer_head * dir_block = NULL; 1776 struct ext3_dir_entry_2 * de; 1777 int err, retries = 0; 1778 1779 if (dir->i_nlink >= EXT3_LINK_MAX) 1780 return -EMLINK; 1781 1782 dquot_initialize(dir); 1783 1784retry: 1785 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1786 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1787 EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb)); 1788 if (IS_ERR(handle)) 1789 return PTR_ERR(handle); 1790 1791 if (IS_DIRSYNC(dir)) 1792 handle->h_sync = 1; 1793 1794 inode = ext3_new_inode (handle, dir, &dentry->d_name, S_IFDIR | mode); 1795 err = PTR_ERR(inode); 1796 if (IS_ERR(inode)) 1797 goto out_stop; 1798 1799 inode->i_op = &ext3_dir_inode_operations; 1800 inode->i_fop = &ext3_dir_operations; 1801 inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize; 1802 dir_block = ext3_bread (handle, inode, 0, 1, &err); 1803 if (!dir_block) 1804 goto out_clear_inode; 1805 1806 BUFFER_TRACE(dir_block, "get_write_access"); 1807 err = ext3_journal_get_write_access(handle, dir_block); 1808 if (err) 1809 goto out_clear_inode; 1810 1811 de = (struct ext3_dir_entry_2 *) dir_block->b_data; 1812 de->inode = cpu_to_le32(inode->i_ino); 1813 de->name_len = 1; 1814 de->rec_len = ext3_rec_len_to_disk(EXT3_DIR_REC_LEN(de->name_len)); 1815 strcpy (de->name, "."); 1816 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1817 de = ext3_next_entry(de); 1818 de->inode = cpu_to_le32(dir->i_ino); 1819 de->rec_len = ext3_rec_len_to_disk(inode->i_sb->s_blocksize - 1820 EXT3_DIR_REC_LEN(1)); 1821 de->name_len = 2; 1822 strcpy (de->name, ".."); 1823 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1824 inode->i_nlink = 2; 1825 BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata"); 1826 err = ext3_journal_dirty_metadata(handle, dir_block); 1827 if (err) 1828 goto out_clear_inode; 1829 1830 err = ext3_mark_inode_dirty(handle, inode); 1831 if (!err) 1832 err = ext3_add_entry (handle, dentry, inode); 1833 1834 if (err) { 1835out_clear_inode: 1836 inode->i_nlink = 0; 1837 unlock_new_inode(inode); 1838 ext3_mark_inode_dirty(handle, inode); 1839 iput (inode); 1840 goto out_stop; 1841 } 1842 inc_nlink(dir); 1843 ext3_update_dx_flag(dir); 1844 err = ext3_mark_inode_dirty(handle, dir); 1845 if (err) 1846 goto out_clear_inode; 1847 1848 d_instantiate(dentry, inode); 1849 unlock_new_inode(inode); 1850out_stop: 1851 brelse(dir_block); 1852 ext3_journal_stop(handle); 1853 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1854 goto retry; 1855 return err; 1856} 1857 1858/* 1859 * routine to check that the specified directory is empty (for rmdir) 1860 */ 1861static int empty_dir (struct inode * inode) 1862{ 1863 unsigned long offset; 1864 struct buffer_head * bh; 1865 struct ext3_dir_entry_2 * de, * de1; 1866 struct super_block * sb; 1867 int err = 0; 1868 1869 sb = inode->i_sb; 1870 if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) || 1871 !(bh = ext3_bread (NULL, inode, 0, 0, &err))) { 1872 if (err) 1873 ext3_error(inode->i_sb, __func__, 1874 "error %d reading directory #%lu offset 0", 1875 err, inode->i_ino); 1876 else 1877 ext3_warning(inode->i_sb, __func__, 1878 "bad directory (dir #%lu) - no data block", 1879 inode->i_ino); 1880 return 1; 1881 } 1882 de = (struct ext3_dir_entry_2 *) bh->b_data; 1883 de1 = ext3_next_entry(de); 1884 if (le32_to_cpu(de->inode) != inode->i_ino || 1885 !le32_to_cpu(de1->inode) || 1886 strcmp (".", de->name) || 1887 strcmp ("..", de1->name)) { 1888 ext3_warning (inode->i_sb, "empty_dir", 1889 "bad directory (dir #%lu) - no `.' or `..'", 1890 inode->i_ino); 1891 brelse (bh); 1892 return 1; 1893 } 1894 offset = ext3_rec_len_from_disk(de->rec_len) + 1895 ext3_rec_len_from_disk(de1->rec_len); 1896 de = ext3_next_entry(de1); 1897 while (offset < inode->i_size ) { 1898 if (!bh || 1899 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 1900 err = 0; 1901 brelse (bh); 1902 bh = ext3_bread (NULL, inode, 1903 offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err); 1904 if (!bh) { 1905 if (err) 1906 ext3_error(sb, __func__, 1907 "error %d reading directory" 1908 " #%lu offset %lu", 1909 err, inode->i_ino, offset); 1910 offset += sb->s_blocksize; 1911 continue; 1912 } 1913 de = (struct ext3_dir_entry_2 *) bh->b_data; 1914 } 1915 if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) { 1916 de = (struct ext3_dir_entry_2 *)(bh->b_data + 1917 sb->s_blocksize); 1918 offset = (offset | (sb->s_blocksize - 1)) + 1; 1919 continue; 1920 } 1921 if (le32_to_cpu(de->inode)) { 1922 brelse (bh); 1923 return 0; 1924 } 1925 offset += ext3_rec_len_from_disk(de->rec_len); 1926 de = ext3_next_entry(de); 1927 } 1928 brelse (bh); 1929 return 1; 1930} 1931 1932/* ext3_orphan_add() links an unlinked or truncated inode into a list of 1933 * such inodes, starting at the superblock, in case we crash before the 1934 * file is closed/deleted, or in case the inode truncate spans multiple 1935 * transactions and the last transaction is not recovered after a crash. 1936 * 1937 * At filesystem recovery time, we walk this list deleting unlinked 1938 * inodes and truncating linked inodes in ext3_orphan_cleanup(). 1939 */ 1940int ext3_orphan_add(handle_t *handle, struct inode *inode) 1941{ 1942 struct super_block *sb = inode->i_sb; 1943 struct ext3_iloc iloc; 1944 int err = 0, rc; 1945 1946 mutex_lock(&EXT3_SB(sb)->s_orphan_lock); 1947 if (!list_empty(&EXT3_I(inode)->i_orphan)) 1948 goto out_unlock; 1949 1950 /* Orphan handling is only valid for files with data blocks 1951 * being truncated, or files being unlinked. */ 1952 1953 /* @@@ FIXME: Observation from aviro: 1954 * I think I can trigger J_ASSERT in ext3_orphan_add(). We block 1955 * here (on s_orphan_lock), so race with ext3_link() which might bump 1956 * ->i_nlink. For, say it, character device. Not a regular file, 1957 * not a directory, not a symlink and ->i_nlink > 0. 1958 * 1959 * tytso, 4/25/2009: I'm not sure how that could happen; 1960 * shouldn't the fs core protect us from these sort of 1961 * unlink()/link() races? 1962 */ 1963 J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 1964 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 1965 1966 BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access"); 1967 err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh); 1968 if (err) 1969 goto out_unlock; 1970 1971 err = ext3_reserve_inode_write(handle, inode, &iloc); 1972 if (err) 1973 goto out_unlock; 1974 1975 /* Insert this inode at the head of the on-disk orphan list... */ 1976 NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan); 1977 EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 1978 err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh); 1979 rc = ext3_mark_iloc_dirty(handle, inode, &iloc); 1980 if (!err) 1981 err = rc; 1982 1983 /* Only add to the head of the in-memory list if all the 1984 * previous operations succeeded. If the orphan_add is going to 1985 * fail (possibly taking the journal offline), we can't risk 1986 * leaving the inode on the orphan list: stray orphan-list 1987 * entries can cause panics at unmount time. 1988 * 1989 * This is safe: on error we're going to ignore the orphan list 1990 * anyway on the next recovery. */ 1991 if (!err) 1992 list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan); 1993 1994 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 1995 jbd_debug(4, "orphan inode %lu will point to %d\n", 1996 inode->i_ino, NEXT_ORPHAN(inode)); 1997out_unlock: 1998 mutex_unlock(&EXT3_SB(sb)->s_orphan_lock); 1999 ext3_std_error(inode->i_sb, err); 2000 return err; 2001} 2002 2003/* 2004 * ext3_orphan_del() removes an unlinked or truncated inode from the list 2005 * of such inodes stored on disk, because it is finally being cleaned up. 2006 */ 2007int ext3_orphan_del(handle_t *handle, struct inode *inode) 2008{ 2009 struct list_head *prev; 2010 struct ext3_inode_info *ei = EXT3_I(inode); 2011 struct ext3_sb_info *sbi; 2012 unsigned long ino_next; 2013 struct ext3_iloc iloc; 2014 int err = 0; 2015 2016 mutex_lock(&EXT3_SB(inode->i_sb)->s_orphan_lock); 2017 if (list_empty(&ei->i_orphan)) 2018 goto out; 2019 2020 ino_next = NEXT_ORPHAN(inode); 2021 prev = ei->i_orphan.prev; 2022 sbi = EXT3_SB(inode->i_sb); 2023 2024 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 2025 2026 list_del_init(&ei->i_orphan); 2027 2028 /* If we're on an error path, we may not have a valid 2029 * transaction handle with which to update the orphan list on 2030 * disk, but we still need to remove the inode from the linked 2031 * list in memory. */ 2032 if (!handle) 2033 goto out; 2034 2035 err = ext3_reserve_inode_write(handle, inode, &iloc); 2036 if (err) 2037 goto out_err; 2038 2039 if (prev == &sbi->s_orphan) { 2040 jbd_debug(4, "superblock will point to %lu\n", ino_next); 2041 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 2042 err = ext3_journal_get_write_access(handle, sbi->s_sbh); 2043 if (err) 2044 goto out_brelse; 2045 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 2046 err = ext3_journal_dirty_metadata(handle, sbi->s_sbh); 2047 } else { 2048 struct ext3_iloc iloc2; 2049 struct inode *i_prev = 2050 &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode; 2051 2052 jbd_debug(4, "orphan inode %lu will point to %lu\n", 2053 i_prev->i_ino, ino_next); 2054 err = ext3_reserve_inode_write(handle, i_prev, &iloc2); 2055 if (err) 2056 goto out_brelse; 2057 NEXT_ORPHAN(i_prev) = ino_next; 2058 err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2); 2059 } 2060 if (err) 2061 goto out_brelse; 2062 NEXT_ORPHAN(inode) = 0; 2063 err = ext3_mark_iloc_dirty(handle, inode, &iloc); 2064 2065out_err: 2066 ext3_std_error(inode->i_sb, err); 2067out: 2068 mutex_unlock(&EXT3_SB(inode->i_sb)->s_orphan_lock); 2069 return err; 2070 2071out_brelse: 2072 brelse(iloc.bh); 2073 goto out_err; 2074} 2075 2076static int ext3_rmdir (struct inode * dir, struct dentry *dentry) 2077{ 2078 int retval; 2079 struct inode * inode; 2080 struct buffer_head * bh; 2081 struct ext3_dir_entry_2 * de; 2082 handle_t *handle; 2083 2084 /* Initialize quotas before so that eventual writes go in 2085 * separate transaction */ 2086 dquot_initialize(dir); 2087 dquot_initialize(dentry->d_inode); 2088 2089 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2090 if (IS_ERR(handle)) 2091 return PTR_ERR(handle); 2092 2093 retval = -ENOENT; 2094 bh = ext3_find_entry(dir, &dentry->d_name, &de); 2095 if (!bh) 2096 goto end_rmdir; 2097 2098 if (IS_DIRSYNC(dir)) 2099 handle->h_sync = 1; 2100 2101 inode = dentry->d_inode; 2102 2103 retval = -EIO; 2104 if (le32_to_cpu(de->inode) != inode->i_ino) 2105 goto end_rmdir; 2106 2107 retval = -ENOTEMPTY; 2108 if (!empty_dir (inode)) 2109 goto end_rmdir; 2110 2111 retval = ext3_delete_entry(handle, dir, de, bh); 2112 if (retval) 2113 goto end_rmdir; 2114 if (inode->i_nlink != 2) 2115 ext3_warning (inode->i_sb, "ext3_rmdir", 2116 "empty directory has nlink!=2 (%d)", 2117 inode->i_nlink); 2118 inode->i_version++; 2119 clear_nlink(inode); 2120 /* There's no need to set i_disksize: the fact that i_nlink is 2121 * zero will ensure that the right thing happens during any 2122 * recovery. */ 2123 inode->i_size = 0; 2124 ext3_orphan_add(handle, inode); 2125 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2126 ext3_mark_inode_dirty(handle, inode); 2127 drop_nlink(dir); 2128 ext3_update_dx_flag(dir); 2129 ext3_mark_inode_dirty(handle, dir); 2130 2131end_rmdir: 2132 ext3_journal_stop(handle); 2133 brelse (bh); 2134 return retval; 2135} 2136 2137static int ext3_unlink(struct inode * dir, struct dentry *dentry) 2138{ 2139 int retval; 2140 struct inode * inode; 2141 struct buffer_head * bh; 2142 struct ext3_dir_entry_2 * de; 2143 handle_t *handle; 2144 2145 trace_ext3_unlink_enter(dir, dentry); 2146 /* Initialize quotas before so that eventual writes go 2147 * in separate transaction */ 2148 dquot_initialize(dir); 2149 dquot_initialize(dentry->d_inode); 2150 2151 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2152 if (IS_ERR(handle)) 2153 return PTR_ERR(handle); 2154 2155 if (IS_DIRSYNC(dir)) 2156 handle->h_sync = 1; 2157 2158 retval = -ENOENT; 2159 bh = ext3_find_entry(dir, &dentry->d_name, &de); 2160 if (!bh) 2161 goto end_unlink; 2162 2163 inode = dentry->d_inode; 2164 2165 retval = -EIO; 2166 if (le32_to_cpu(de->inode) != inode->i_ino) 2167 goto end_unlink; 2168 2169 if (!inode->i_nlink) { 2170 ext3_warning (inode->i_sb, "ext3_unlink", 2171 "Deleting nonexistent file (%lu), %d", 2172 inode->i_ino, inode->i_nlink); 2173 inode->i_nlink = 1; 2174 } 2175 retval = ext3_delete_entry(handle, dir, de, bh); 2176 if (retval) 2177 goto end_unlink; 2178 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2179 ext3_update_dx_flag(dir); 2180 ext3_mark_inode_dirty(handle, dir); 2181 drop_nlink(inode); 2182 if (!inode->i_nlink) 2183 ext3_orphan_add(handle, inode); 2184 inode->i_ctime = dir->i_ctime; 2185 ext3_mark_inode_dirty(handle, inode); 2186 retval = 0; 2187 2188end_unlink: 2189 ext3_journal_stop(handle); 2190 brelse (bh); 2191 trace_ext3_unlink_exit(dentry, retval); 2192 return retval; 2193} 2194 2195static int ext3_symlink (struct inode * dir, 2196 struct dentry *dentry, const char * symname) 2197{ 2198 handle_t *handle; 2199 struct inode * inode; 2200 int l, err, retries = 0; 2201 int credits; 2202 2203 l = strlen(symname)+1; 2204 if (l > dir->i_sb->s_blocksize) 2205 return -ENAMETOOLONG; 2206 2207 dquot_initialize(dir); 2208 2209 if (l > EXT3_N_BLOCKS * 4) { 2210 /* 2211 * For non-fast symlinks, we just allocate inode and put it on 2212 * orphan list in the first transaction => we need bitmap, 2213 * group descriptor, sb, inode block, quota blocks, and 2214 * possibly selinux xattr blocks. 2215 */ 2216 credits = 4 + EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + 2217 EXT3_XATTR_TRANS_BLOCKS; 2218 } else { 2219 /* 2220 * Fast symlink. We have to add entry to directory 2221 * (EXT3_DATA_TRANS_BLOCKS + EXT3_INDEX_EXTRA_TRANS_BLOCKS), 2222 * allocate new inode (bitmap, group descriptor, inode block, 2223 * quota blocks, sb is already counted in previous macros). 2224 */ 2225 credits = EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2226 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 2227 EXT3_MAXQUOTAS_INIT_BLOCKS(dir->i_sb); 2228 } 2229retry: 2230 handle = ext3_journal_start(dir, credits); 2231 if (IS_ERR(handle)) 2232 return PTR_ERR(handle); 2233 2234 if (IS_DIRSYNC(dir)) 2235 handle->h_sync = 1; 2236 2237 inode = ext3_new_inode (handle, dir, &dentry->d_name, S_IFLNK|S_IRWXUGO); 2238 err = PTR_ERR(inode); 2239 if (IS_ERR(inode)) 2240 goto out_stop; 2241 2242 if (l > EXT3_N_BLOCKS * 4) { 2243 inode->i_op = &ext3_symlink_inode_operations; 2244 ext3_set_aops(inode); 2245 /* 2246 * We cannot call page_symlink() with transaction started 2247 * because it calls into ext3_write_begin() which acquires page 2248 * lock which ranks below transaction start (and it can also 2249 * wait for journal commit if we are running out of space). So 2250 * we have to stop transaction now and restart it when symlink 2251 * contents is written. 2252 * 2253 * To keep fs consistent in case of crash, we have to put inode 2254 * to orphan list in the mean time. 2255 */ 2256 drop_nlink(inode); 2257 err = ext3_orphan_add(handle, inode); 2258 ext3_journal_stop(handle); 2259 if (err) 2260 goto err_drop_inode; 2261 err = __page_symlink(inode, symname, l, 1); 2262 if (err) 2263 goto err_drop_inode; 2264 /* 2265 * Now inode is being linked into dir (EXT3_DATA_TRANS_BLOCKS 2266 * + EXT3_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified 2267 */ 2268 handle = ext3_journal_start(dir, 2269 EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2270 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 1); 2271 if (IS_ERR(handle)) { 2272 err = PTR_ERR(handle); 2273 goto err_drop_inode; 2274 } 2275 inc_nlink(inode); 2276 err = ext3_orphan_del(handle, inode); 2277 if (err) { 2278 ext3_journal_stop(handle); 2279 drop_nlink(inode); 2280 goto err_drop_inode; 2281 } 2282 } else { 2283 inode->i_op = &ext3_fast_symlink_inode_operations; 2284 memcpy((char*)&EXT3_I(inode)->i_data,symname,l); 2285 inode->i_size = l-1; 2286 } 2287 EXT3_I(inode)->i_disksize = inode->i_size; 2288 err = ext3_add_nondir(handle, dentry, inode); 2289out_stop: 2290 ext3_journal_stop(handle); 2291 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2292 goto retry; 2293 return err; 2294err_drop_inode: 2295 unlock_new_inode(inode); 2296 iput(inode); 2297 return err; 2298} 2299 2300static int ext3_link (struct dentry * old_dentry, 2301 struct inode * dir, struct dentry *dentry) 2302{ 2303 handle_t *handle; 2304 struct inode *inode = old_dentry->d_inode; 2305 int err, retries = 0; 2306 2307 if (inode->i_nlink >= EXT3_LINK_MAX) 2308 return -EMLINK; 2309 2310 dquot_initialize(dir); 2311 2312retry: 2313 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2314 EXT3_INDEX_EXTRA_TRANS_BLOCKS); 2315 if (IS_ERR(handle)) 2316 return PTR_ERR(handle); 2317 2318 if (IS_DIRSYNC(dir)) 2319 handle->h_sync = 1; 2320 2321 inode->i_ctime = CURRENT_TIME_SEC; 2322 inc_nlink(inode); 2323 ihold(inode); 2324 2325 err = ext3_add_entry(handle, dentry, inode); 2326 if (!err) { 2327 ext3_mark_inode_dirty(handle, inode); 2328 d_instantiate(dentry, inode); 2329 } else { 2330 drop_nlink(inode); 2331 iput(inode); 2332 } 2333 ext3_journal_stop(handle); 2334 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2335 goto retry; 2336 return err; 2337} 2338 2339#define PARENT_INO(buffer) \ 2340 (ext3_next_entry((struct ext3_dir_entry_2 *)(buffer))->inode) 2341 2342/* 2343 * Anybody can rename anything with this: the permission checks are left to the 2344 * higher-level routines. 2345 */ 2346static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, 2347 struct inode * new_dir,struct dentry *new_dentry) 2348{ 2349 handle_t *handle; 2350 struct inode * old_inode, * new_inode; 2351 struct buffer_head * old_bh, * new_bh, * dir_bh; 2352 struct ext3_dir_entry_2 * old_de, * new_de; 2353 int retval, flush_file = 0; 2354 2355 dquot_initialize(old_dir); 2356 dquot_initialize(new_dir); 2357 2358 old_bh = new_bh = dir_bh = NULL; 2359 2360 /* Initialize quotas before so that eventual writes go 2361 * in separate transaction */ 2362 if (new_dentry->d_inode) 2363 dquot_initialize(new_dentry->d_inode); 2364 handle = ext3_journal_start(old_dir, 2 * 2365 EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) + 2366 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2); 2367 if (IS_ERR(handle)) 2368 return PTR_ERR(handle); 2369 2370 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) 2371 handle->h_sync = 1; 2372 2373 old_bh = ext3_find_entry(old_dir, &old_dentry->d_name, &old_de); 2374 /* 2375 * Check for inode number is _not_ due to possible IO errors. 2376 * We might rmdir the source, keep it as pwd of some process 2377 * and merrily kill the link to whatever was created under the 2378 * same name. Goodbye sticky bit ;-< 2379 */ 2380 old_inode = old_dentry->d_inode; 2381 retval = -ENOENT; 2382 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino) 2383 goto end_rename; 2384 2385 new_inode = new_dentry->d_inode; 2386 new_bh = ext3_find_entry(new_dir, &new_dentry->d_name, &new_de); 2387 if (new_bh) { 2388 if (!new_inode) { 2389 brelse (new_bh); 2390 new_bh = NULL; 2391 } 2392 } 2393 if (S_ISDIR(old_inode->i_mode)) { 2394 if (new_inode) { 2395 retval = -ENOTEMPTY; 2396 if (!empty_dir (new_inode)) 2397 goto end_rename; 2398 } 2399 retval = -EIO; 2400 dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval); 2401 if (!dir_bh) 2402 goto end_rename; 2403 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino) 2404 goto end_rename; 2405 retval = -EMLINK; 2406 if (!new_inode && new_dir!=old_dir && 2407 new_dir->i_nlink >= EXT3_LINK_MAX) 2408 goto end_rename; 2409 } 2410 if (!new_bh) { 2411 retval = ext3_add_entry (handle, new_dentry, old_inode); 2412 if (retval) 2413 goto end_rename; 2414 } else { 2415 BUFFER_TRACE(new_bh, "get write access"); 2416 retval = ext3_journal_get_write_access(handle, new_bh); 2417 if (retval) 2418 goto journal_error; 2419 new_de->inode = cpu_to_le32(old_inode->i_ino); 2420 if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb, 2421 EXT3_FEATURE_INCOMPAT_FILETYPE)) 2422 new_de->file_type = old_de->file_type; 2423 new_dir->i_version++; 2424 new_dir->i_ctime = new_dir->i_mtime = CURRENT_TIME_SEC; 2425 ext3_mark_inode_dirty(handle, new_dir); 2426 BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata"); 2427 retval = ext3_journal_dirty_metadata(handle, new_bh); 2428 if (retval) 2429 goto journal_error; 2430 brelse(new_bh); 2431 new_bh = NULL; 2432 } 2433 2434 /* 2435 * Like most other Unix systems, set the ctime for inodes on a 2436 * rename. 2437 */ 2438 old_inode->i_ctime = CURRENT_TIME_SEC; 2439 ext3_mark_inode_dirty(handle, old_inode); 2440 2441 /* 2442 * ok, that's it 2443 */ 2444 if (le32_to_cpu(old_de->inode) != old_inode->i_ino || 2445 old_de->name_len != old_dentry->d_name.len || 2446 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) || 2447 (retval = ext3_delete_entry(handle, old_dir, 2448 old_de, old_bh)) == -ENOENT) { 2449 /* old_de could have moved from under us during htree split, so 2450 * make sure that we are deleting the right entry. We might 2451 * also be pointing to a stale entry in the unused part of 2452 * old_bh so just checking inum and the name isn't enough. */ 2453 struct buffer_head *old_bh2; 2454 struct ext3_dir_entry_2 *old_de2; 2455 2456 old_bh2 = ext3_find_entry(old_dir, &old_dentry->d_name, 2457 &old_de2); 2458 if (old_bh2) { 2459 retval = ext3_delete_entry(handle, old_dir, 2460 old_de2, old_bh2); 2461 brelse(old_bh2); 2462 } 2463 } 2464 if (retval) { 2465 ext3_warning(old_dir->i_sb, "ext3_rename", 2466 "Deleting old file (%lu), %d, error=%d", 2467 old_dir->i_ino, old_dir->i_nlink, retval); 2468 } 2469 2470 if (new_inode) { 2471 drop_nlink(new_inode); 2472 new_inode->i_ctime = CURRENT_TIME_SEC; 2473 } 2474 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; 2475 ext3_update_dx_flag(old_dir); 2476 if (dir_bh) { 2477 BUFFER_TRACE(dir_bh, "get_write_access"); 2478 retval = ext3_journal_get_write_access(handle, dir_bh); 2479 if (retval) 2480 goto journal_error; 2481 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino); 2482 BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata"); 2483 retval = ext3_journal_dirty_metadata(handle, dir_bh); 2484 if (retval) { 2485journal_error: 2486 ext3_std_error(new_dir->i_sb, retval); 2487 goto end_rename; 2488 } 2489 drop_nlink(old_dir); 2490 if (new_inode) { 2491 drop_nlink(new_inode); 2492 } else { 2493 inc_nlink(new_dir); 2494 ext3_update_dx_flag(new_dir); 2495 ext3_mark_inode_dirty(handle, new_dir); 2496 } 2497 } 2498 ext3_mark_inode_dirty(handle, old_dir); 2499 if (new_inode) { 2500 ext3_mark_inode_dirty(handle, new_inode); 2501 if (!new_inode->i_nlink) 2502 ext3_orphan_add(handle, new_inode); 2503 if (ext3_should_writeback_data(new_inode)) 2504 flush_file = 1; 2505 } 2506 retval = 0; 2507 2508end_rename: 2509 brelse (dir_bh); 2510 brelse (old_bh); 2511 brelse (new_bh); 2512 ext3_journal_stop(handle); 2513 if (retval == 0 && flush_file) 2514 filemap_flush(old_inode->i_mapping); 2515 return retval; 2516} 2517 2518/* 2519 * directories can handle most operations... 2520 */ 2521const struct inode_operations ext3_dir_inode_operations = { 2522 .create = ext3_create, 2523 .lookup = ext3_lookup, 2524 .link = ext3_link, 2525 .unlink = ext3_unlink, 2526 .symlink = ext3_symlink, 2527 .mkdir = ext3_mkdir, 2528 .rmdir = ext3_rmdir, 2529 .mknod = ext3_mknod, 2530 .rename = ext3_rename, 2531 .setattr = ext3_setattr, 2532#ifdef CONFIG_EXT3_FS_XATTR 2533 .setxattr = generic_setxattr, 2534 .getxattr = generic_getxattr, 2535 .listxattr = ext3_listxattr, 2536 .removexattr = generic_removexattr, 2537#endif 2538 .get_acl = ext3_get_acl, 2539}; 2540 2541const struct inode_operations ext3_special_inode_operations = { 2542 .setattr = ext3_setattr, 2543#ifdef CONFIG_EXT3_FS_XATTR 2544 .setxattr = generic_setxattr, 2545 .getxattr = generic_getxattr, 2546 .listxattr = ext3_listxattr, 2547 .removexattr = generic_removexattr, 2548#endif 2549 .get_acl = ext3_get_acl, 2550}; 2551