namei.c revision eee194e76c681dbdbf5024b889fda1181b66ef57
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/smp_lock.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 u32 offs; 144}; 145 146#ifdef CONFIG_EXT3_INDEX 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 * Future: use high four bits of block for coalesce-on-delete flags 181 * Mask them off for now. 182 */ 183 184static inline unsigned dx_get_block (struct dx_entry *entry) 185{ 186 return le32_to_cpu(entry->block) & 0x00ffffff; 187} 188 189static inline void dx_set_block (struct dx_entry *entry, unsigned value) 190{ 191 entry->block = cpu_to_le32(value); 192} 193 194static inline unsigned dx_get_hash (struct dx_entry *entry) 195{ 196 return le32_to_cpu(entry->hash); 197} 198 199static inline void dx_set_hash (struct dx_entry *entry, unsigned value) 200{ 201 entry->hash = cpu_to_le32(value); 202} 203 204static inline unsigned dx_get_count (struct dx_entry *entries) 205{ 206 return le16_to_cpu(((struct dx_countlimit *) entries)->count); 207} 208 209static inline unsigned dx_get_limit (struct dx_entry *entries) 210{ 211 return le16_to_cpu(((struct dx_countlimit *) entries)->limit); 212} 213 214static inline void dx_set_count (struct dx_entry *entries, unsigned value) 215{ 216 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); 217} 218 219static inline void dx_set_limit (struct dx_entry *entries, unsigned value) 220{ 221 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); 222} 223 224static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize) 225{ 226 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) - 227 EXT3_DIR_REC_LEN(2) - infosize; 228 return 0? 20: entry_space / sizeof(struct dx_entry); 229} 230 231static inline unsigned dx_node_limit (struct inode *dir) 232{ 233 unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0); 234 return 0? 22: entry_space / sizeof(struct dx_entry); 235} 236 237/* 238 * Debug 239 */ 240#ifdef DX_DEBUG 241static void dx_show_index (char * label, struct dx_entry *entries) 242{ 243 int i, n = dx_get_count (entries); 244 printk("%s index ", label); 245 for (i = 0; i < n; i++) 246 { 247 printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i)); 248 } 249 printk("\n"); 250} 251 252struct stats 253{ 254 unsigned names; 255 unsigned space; 256 unsigned bcount; 257}; 258 259static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de, 260 int size, int show_names) 261{ 262 unsigned names = 0, space = 0; 263 char *base = (char *) de; 264 struct dx_hash_info h = *hinfo; 265 266 printk("names: "); 267 while ((char *) de < base + size) 268 { 269 if (de->inode) 270 { 271 if (show_names) 272 { 273 int len = de->name_len; 274 char *name = de->name; 275 while (len--) printk("%c", *name++); 276 ext3fs_dirhash(de->name, de->name_len, &h); 277 printk(":%x.%u ", h.hash, 278 ((char *) de - base)); 279 } 280 space += EXT3_DIR_REC_LEN(de->name_len); 281 names++; 282 } 283 de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); 284 } 285 printk("(%i)\n", names); 286 return (struct stats) { names, space, 1 }; 287} 288 289struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, 290 struct dx_entry *entries, int levels) 291{ 292 unsigned blocksize = dir->i_sb->s_blocksize; 293 unsigned count = dx_get_count (entries), names = 0, space = 0, i; 294 unsigned bcount = 0; 295 struct buffer_head *bh; 296 int err; 297 printk("%i indexed blocks...\n", count); 298 for (i = 0; i < count; i++, entries++) 299 { 300 u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0; 301 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; 302 struct stats stats; 303 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); 304 if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue; 305 stats = levels? 306 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): 307 dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0); 308 names += stats.names; 309 space += stats.space; 310 bcount += stats.bcount; 311 brelse (bh); 312 } 313 if (bcount) 314 printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ", 315 names, space/bcount,(space/bcount)*100/blocksize); 316 return (struct stats) { names, space, bcount}; 317} 318#endif /* DX_DEBUG */ 319 320/* 321 * Probe for a directory leaf block to search. 322 * 323 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format 324 * error in the directory index, and the caller should fall back to 325 * searching the directory normally. The callers of dx_probe **MUST** 326 * check for this error code, and make sure it never gets reflected 327 * back to userspace. 328 */ 329static struct dx_frame * 330dx_probe(struct dentry *dentry, struct inode *dir, 331 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err) 332{ 333 unsigned count, indirect; 334 struct dx_entry *at, *entries, *p, *q, *m; 335 struct dx_root *root; 336 struct buffer_head *bh; 337 struct dx_frame *frame = frame_in; 338 u32 hash; 339 340 frame->bh = NULL; 341 if (dentry) 342 dir = dentry->d_parent->d_inode; 343 if (!(bh = ext3_bread (NULL,dir, 0, 0, err))) 344 goto fail; 345 root = (struct dx_root *) bh->b_data; 346 if (root->info.hash_version != DX_HASH_TEA && 347 root->info.hash_version != DX_HASH_HALF_MD4 && 348 root->info.hash_version != DX_HASH_LEGACY) { 349 ext3_warning(dir->i_sb, __FUNCTION__, 350 "Unrecognised inode hash code %d", 351 root->info.hash_version); 352 brelse(bh); 353 *err = ERR_BAD_DX_DIR; 354 goto fail; 355 } 356 hinfo->hash_version = root->info.hash_version; 357 hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed; 358 if (dentry) 359 ext3fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo); 360 hash = hinfo->hash; 361 362 if (root->info.unused_flags & 1) { 363 ext3_warning(dir->i_sb, __FUNCTION__, 364 "Unimplemented inode hash flags: %#06x", 365 root->info.unused_flags); 366 brelse(bh); 367 *err = ERR_BAD_DX_DIR; 368 goto fail; 369 } 370 371 if ((indirect = root->info.indirect_levels) > 1) { 372 ext3_warning(dir->i_sb, __FUNCTION__, 373 "Unimplemented inode hash depth: %#06x", 374 root->info.indirect_levels); 375 brelse(bh); 376 *err = ERR_BAD_DX_DIR; 377 goto fail; 378 } 379 380 entries = (struct dx_entry *) (((char *)&root->info) + 381 root->info.info_length); 382 assert(dx_get_limit(entries) == dx_root_limit(dir, 383 root->info.info_length)); 384 dxtrace (printk("Look up %x", hash)); 385 while (1) 386 { 387 count = dx_get_count(entries); 388 assert (count && count <= dx_get_limit(entries)); 389 p = entries + 1; 390 q = entries + count - 1; 391 while (p <= q) 392 { 393 m = p + (q - p)/2; 394 dxtrace(printk(".")); 395 if (dx_get_hash(m) > hash) 396 q = m - 1; 397 else 398 p = m + 1; 399 } 400 401 if (0) // linear search cross check 402 { 403 unsigned n = count - 1; 404 at = entries; 405 while (n--) 406 { 407 dxtrace(printk(",")); 408 if (dx_get_hash(++at) > hash) 409 { 410 at--; 411 break; 412 } 413 } 414 assert (at == p - 1); 415 } 416 417 at = p - 1; 418 dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at))); 419 frame->bh = bh; 420 frame->entries = entries; 421 frame->at = at; 422 if (!indirect--) return frame; 423 if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err))) 424 goto fail2; 425 at = entries = ((struct dx_node *) bh->b_data)->entries; 426 assert (dx_get_limit(entries) == dx_node_limit (dir)); 427 frame++; 428 } 429fail2: 430 while (frame >= frame_in) { 431 brelse(frame->bh); 432 frame--; 433 } 434fail: 435 return NULL; 436} 437 438static void dx_release (struct dx_frame *frames) 439{ 440 if (frames[0].bh == NULL) 441 return; 442 443 if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels) 444 brelse(frames[1].bh); 445 brelse(frames[0].bh); 446} 447 448/* 449 * This function increments the frame pointer to search the next leaf 450 * block, and reads in the necessary intervening nodes if the search 451 * should be necessary. Whether or not the search is necessary is 452 * controlled by the hash parameter. If the hash value is even, then 453 * the search is only continued if the next block starts with that 454 * hash value. This is used if we are searching for a specific file. 455 * 456 * If the hash value is HASH_NB_ALWAYS, then always go to the next block. 457 * 458 * This function returns 1 if the caller should continue to search, 459 * or 0 if it should not. If there is an error reading one of the 460 * index blocks, it will a negative error code. 461 * 462 * If start_hash is non-null, it will be filled in with the starting 463 * hash of the next page. 464 */ 465static int ext3_htree_next_block(struct inode *dir, __u32 hash, 466 struct dx_frame *frame, 467 struct dx_frame *frames, 468 __u32 *start_hash) 469{ 470 struct dx_frame *p; 471 struct buffer_head *bh; 472 int err, num_frames = 0; 473 __u32 bhash; 474 475 p = frame; 476 /* 477 * Find the next leaf page by incrementing the frame pointer. 478 * If we run out of entries in the interior node, loop around and 479 * increment pointer in the parent node. When we break out of 480 * this loop, num_frames indicates the number of interior 481 * nodes need to be read. 482 */ 483 while (1) { 484 if (++(p->at) < p->entries + dx_get_count(p->entries)) 485 break; 486 if (p == frames) 487 return 0; 488 num_frames++; 489 p--; 490 } 491 492 /* 493 * If the hash is 1, then continue only if the next page has a 494 * continuation hash of any value. This is used for readdir 495 * handling. Otherwise, check to see if the hash matches the 496 * desired contiuation hash. If it doesn't, return since 497 * there's no point to read in the successive index pages. 498 */ 499 bhash = dx_get_hash(p->at); 500 if (start_hash) 501 *start_hash = bhash; 502 if ((hash & 1) == 0) { 503 if ((bhash & ~1) != hash) 504 return 0; 505 } 506 /* 507 * If the hash is HASH_NB_ALWAYS, we always go to the next 508 * block so no check is necessary 509 */ 510 while (num_frames--) { 511 if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at), 512 0, &err))) 513 return err; /* Failure */ 514 p++; 515 brelse (p->bh); 516 p->bh = bh; 517 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; 518 } 519 return 1; 520} 521 522 523/* 524 * p is at least 6 bytes before the end of page 525 */ 526static inline struct ext3_dir_entry_2 *ext3_next_entry(struct ext3_dir_entry_2 *p) 527{ 528 return (struct ext3_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len)); 529} 530 531/* 532 * This function fills a red-black tree with information from a 533 * directory block. It returns the number directory entries loaded 534 * into the tree. If there is an error it is returned in err. 535 */ 536static int htree_dirblock_to_tree(struct file *dir_file, 537 struct inode *dir, int block, 538 struct dx_hash_info *hinfo, 539 __u32 start_hash, __u32 start_minor_hash) 540{ 541 struct buffer_head *bh; 542 struct ext3_dir_entry_2 *de, *top; 543 int err, count = 0; 544 545 dxtrace(printk("In htree dirblock_to_tree: block %d\n", block)); 546 if (!(bh = ext3_bread (NULL, dir, block, 0, &err))) 547 return err; 548 549 de = (struct ext3_dir_entry_2 *) bh->b_data; 550 top = (struct ext3_dir_entry_2 *) ((char *) de + 551 dir->i_sb->s_blocksize - 552 EXT3_DIR_REC_LEN(0)); 553 for (; de < top; de = ext3_next_entry(de)) { 554 ext3fs_dirhash(de->name, de->name_len, hinfo); 555 if ((hinfo->hash < start_hash) || 556 ((hinfo->hash == start_hash) && 557 (hinfo->minor_hash < start_minor_hash))) 558 continue; 559 if (de->inode == 0) 560 continue; 561 if ((err = ext3_htree_store_dirent(dir_file, 562 hinfo->hash, hinfo->minor_hash, de)) != 0) { 563 brelse(bh); 564 return err; 565 } 566 count++; 567 } 568 brelse(bh); 569 return count; 570} 571 572 573/* 574 * This function fills a red-black tree with information from a 575 * directory. We start scanning the directory in hash order, starting 576 * at start_hash and start_minor_hash. 577 * 578 * This function returns the number of entries inserted into the tree, 579 * or a negative error code. 580 */ 581int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash, 582 __u32 start_minor_hash, __u32 *next_hash) 583{ 584 struct dx_hash_info hinfo; 585 struct ext3_dir_entry_2 *de; 586 struct dx_frame frames[2], *frame; 587 struct inode *dir; 588 int block, err; 589 int count = 0; 590 int ret; 591 __u32 hashval; 592 593 dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash, 594 start_minor_hash)); 595 dir = dir_file->f_dentry->d_inode; 596 if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) { 597 hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 598 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 599 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, 600 start_hash, start_minor_hash); 601 *next_hash = ~0; 602 return count; 603 } 604 hinfo.hash = start_hash; 605 hinfo.minor_hash = 0; 606 frame = dx_probe(NULL, dir_file->f_dentry->d_inode, &hinfo, frames, &err); 607 if (!frame) 608 return err; 609 610 /* Add '.' and '..' from the htree header */ 611 if (!start_hash && !start_minor_hash) { 612 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 613 if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0) 614 goto errout; 615 count++; 616 } 617 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { 618 de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; 619 de = ext3_next_entry(de); 620 if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0) 621 goto errout; 622 count++; 623 } 624 625 while (1) { 626 block = dx_get_block(frame->at); 627 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, 628 start_hash, start_minor_hash); 629 if (ret < 0) { 630 err = ret; 631 goto errout; 632 } 633 count += ret; 634 hashval = ~0; 635 ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS, 636 frame, frames, &hashval); 637 *next_hash = hashval; 638 if (ret < 0) { 639 err = ret; 640 goto errout; 641 } 642 /* 643 * Stop if: (a) there are no more entries, or 644 * (b) we have inserted at least one entry and the 645 * next hash value is not a continuation 646 */ 647 if ((ret == 0) || 648 (count && ((hashval & 1) == 0))) 649 break; 650 } 651 dx_release(frames); 652 dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n", 653 count, *next_hash)); 654 return count; 655errout: 656 dx_release(frames); 657 return (err); 658} 659 660 661/* 662 * Directory block splitting, compacting 663 */ 664 665static int dx_make_map (struct ext3_dir_entry_2 *de, int size, 666 struct dx_hash_info *hinfo, struct dx_map_entry *map_tail) 667{ 668 int count = 0; 669 char *base = (char *) de; 670 struct dx_hash_info h = *hinfo; 671 672 while ((char *) de < base + size) 673 { 674 if (de->name_len && de->inode) { 675 ext3fs_dirhash(de->name, de->name_len, &h); 676 map_tail--; 677 map_tail->hash = h.hash; 678 map_tail->offs = (u32) ((char *) de - base); 679 count++; 680 cond_resched(); 681 } 682 /* XXX: do we need to check rec_len == 0 case? -Chris */ 683 de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); 684 } 685 return count; 686} 687 688static void dx_sort_map (struct dx_map_entry *map, unsigned count) 689{ 690 struct dx_map_entry *p, *q, *top = map + count - 1; 691 int more; 692 /* Combsort until bubble sort doesn't suck */ 693 while (count > 2) 694 { 695 count = count*10/13; 696 if (count - 9 < 2) /* 9, 10 -> 11 */ 697 count = 11; 698 for (p = top, q = p - count; q >= map; p--, q--) 699 if (p->hash < q->hash) 700 swap(*p, *q); 701 } 702 /* Garden variety bubble sort */ 703 do { 704 more = 0; 705 q = top; 706 while (q-- > map) 707 { 708 if (q[1].hash >= q[0].hash) 709 continue; 710 swap(*(q+1), *q); 711 more = 1; 712 } 713 } while(more); 714} 715 716static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block) 717{ 718 struct dx_entry *entries = frame->entries; 719 struct dx_entry *old = frame->at, *new = old + 1; 720 int count = dx_get_count(entries); 721 722 assert(count < dx_get_limit(entries)); 723 assert(old < entries + count); 724 memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); 725 dx_set_hash(new, hash); 726 dx_set_block(new, block); 727 dx_set_count(entries, count + 1); 728} 729#endif 730 731 732static void ext3_update_dx_flag(struct inode *inode) 733{ 734 if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb, 735 EXT3_FEATURE_COMPAT_DIR_INDEX)) 736 EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL; 737} 738 739/* 740 * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure. 741 * 742 * `len <= EXT3_NAME_LEN' is guaranteed by caller. 743 * `de != NULL' is guaranteed by caller. 744 */ 745static inline int ext3_match (int len, const char * const name, 746 struct ext3_dir_entry_2 * de) 747{ 748 if (len != de->name_len) 749 return 0; 750 if (!de->inode) 751 return 0; 752 return !memcmp(name, de->name, len); 753} 754 755/* 756 * Returns 0 if not found, -1 on failure, and 1 on success 757 */ 758static inline int search_dirblock(struct buffer_head * bh, 759 struct inode *dir, 760 struct dentry *dentry, 761 unsigned long offset, 762 struct ext3_dir_entry_2 ** res_dir) 763{ 764 struct ext3_dir_entry_2 * de; 765 char * dlimit; 766 int de_len; 767 const char *name = dentry->d_name.name; 768 int namelen = dentry->d_name.len; 769 770 de = (struct ext3_dir_entry_2 *) bh->b_data; 771 dlimit = bh->b_data + dir->i_sb->s_blocksize; 772 while ((char *) de < dlimit) { 773 /* this code is executed quadratically often */ 774 /* do minimal checking `by hand' */ 775 776 if ((char *) de + namelen <= dlimit && 777 ext3_match (namelen, name, de)) { 778 /* found a match - just to be sure, do a full check */ 779 if (!ext3_check_dir_entry("ext3_find_entry", 780 dir, de, bh, offset)) 781 return -1; 782 *res_dir = de; 783 return 1; 784 } 785 /* prevent looping on a bad block */ 786 de_len = le16_to_cpu(de->rec_len); 787 if (de_len <= 0) 788 return -1; 789 offset += de_len; 790 de = (struct ext3_dir_entry_2 *) ((char *) de + de_len); 791 } 792 return 0; 793} 794 795 796/* 797 * ext3_find_entry() 798 * 799 * finds an entry in the specified directory with the wanted name. It 800 * returns the cache buffer in which the entry was found, and the entry 801 * itself (as a parameter - res_dir). It does NOT read the inode of the 802 * entry - you'll have to do that yourself if you want to. 803 * 804 * The returned buffer_head has ->b_count elevated. The caller is expected 805 * to brelse() it when appropriate. 806 */ 807static struct buffer_head * ext3_find_entry (struct dentry *dentry, 808 struct ext3_dir_entry_2 ** res_dir) 809{ 810 struct super_block * sb; 811 struct buffer_head * bh_use[NAMEI_RA_SIZE]; 812 struct buffer_head * bh, *ret = NULL; 813 unsigned long start, block, b; 814 int ra_max = 0; /* Number of bh's in the readahead 815 buffer, bh_use[] */ 816 int ra_ptr = 0; /* Current index into readahead 817 buffer */ 818 int num = 0; 819 int nblocks, i, err; 820 struct inode *dir = dentry->d_parent->d_inode; 821 int namelen; 822 const u8 *name; 823 unsigned blocksize; 824 825 *res_dir = NULL; 826 sb = dir->i_sb; 827 blocksize = sb->s_blocksize; 828 namelen = dentry->d_name.len; 829 name = dentry->d_name.name; 830 if (namelen > EXT3_NAME_LEN) 831 return NULL; 832#ifdef CONFIG_EXT3_INDEX 833 if (is_dx(dir)) { 834 bh = ext3_dx_find_entry(dentry, res_dir, &err); 835 /* 836 * On success, or if the error was file not found, 837 * return. Otherwise, fall back to doing a search the 838 * old fashioned way. 839 */ 840 if (bh || (err != ERR_BAD_DX_DIR)) 841 return bh; 842 dxtrace(printk("ext3_find_entry: dx failed, falling back\n")); 843 } 844#endif 845 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); 846 start = EXT3_I(dir)->i_dir_start_lookup; 847 if (start >= nblocks) 848 start = 0; 849 block = start; 850restart: 851 do { 852 /* 853 * We deal with the read-ahead logic here. 854 */ 855 if (ra_ptr >= ra_max) { 856 /* Refill the readahead buffer */ 857 ra_ptr = 0; 858 b = block; 859 for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) { 860 /* 861 * Terminate if we reach the end of the 862 * directory and must wrap, or if our 863 * search has finished at this block. 864 */ 865 if (b >= nblocks || (num && block == start)) { 866 bh_use[ra_max] = NULL; 867 break; 868 } 869 num++; 870 bh = ext3_getblk(NULL, dir, b++, 0, &err); 871 bh_use[ra_max] = bh; 872 if (bh) 873 ll_rw_block(READ, 1, &bh); 874 } 875 } 876 if ((bh = bh_use[ra_ptr++]) == NULL) 877 goto next; 878 wait_on_buffer(bh); 879 if (!buffer_uptodate(bh)) { 880 /* read error, skip block & hope for the best */ 881 ext3_error(sb, __FUNCTION__, "reading directory #%lu " 882 "offset %lu", dir->i_ino, block); 883 brelse(bh); 884 goto next; 885 } 886 i = search_dirblock(bh, dir, dentry, 887 block << EXT3_BLOCK_SIZE_BITS(sb), res_dir); 888 if (i == 1) { 889 EXT3_I(dir)->i_dir_start_lookup = block; 890 ret = bh; 891 goto cleanup_and_exit; 892 } else { 893 brelse(bh); 894 if (i < 0) 895 goto cleanup_and_exit; 896 } 897 next: 898 if (++block >= nblocks) 899 block = 0; 900 } while (block != start); 901 902 /* 903 * If the directory has grown while we were searching, then 904 * search the last part of the directory before giving up. 905 */ 906 block = nblocks; 907 nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); 908 if (block < nblocks) { 909 start = 0; 910 goto restart; 911 } 912 913cleanup_and_exit: 914 /* Clean up the read-ahead blocks */ 915 for (; ra_ptr < ra_max; ra_ptr++) 916 brelse (bh_use[ra_ptr]); 917 return ret; 918} 919 920#ifdef CONFIG_EXT3_INDEX 921static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry, 922 struct ext3_dir_entry_2 **res_dir, int *err) 923{ 924 struct super_block * sb; 925 struct dx_hash_info hinfo; 926 u32 hash; 927 struct dx_frame frames[2], *frame; 928 struct ext3_dir_entry_2 *de, *top; 929 struct buffer_head *bh; 930 unsigned long block; 931 int retval; 932 int namelen = dentry->d_name.len; 933 const u8 *name = dentry->d_name.name; 934 struct inode *dir = dentry->d_parent->d_inode; 935 936 sb = dir->i_sb; 937 /* NFS may look up ".." - look at dx_root directory block */ 938 if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){ 939 if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err))) 940 return NULL; 941 } else { 942 frame = frames; 943 frame->bh = NULL; /* for dx_release() */ 944 frame->at = (struct dx_entry *)frames; /* hack for zero entry*/ 945 dx_set_block(frame->at, 0); /* dx_root block is 0 */ 946 } 947 hash = hinfo.hash; 948 do { 949 block = dx_get_block(frame->at); 950 if (!(bh = ext3_bread (NULL,dir, block, 0, err))) 951 goto errout; 952 de = (struct ext3_dir_entry_2 *) bh->b_data; 953 top = (struct ext3_dir_entry_2 *) ((char *) de + sb->s_blocksize - 954 EXT3_DIR_REC_LEN(0)); 955 for (; de < top; de = ext3_next_entry(de)) 956 if (ext3_match (namelen, name, de)) { 957 if (!ext3_check_dir_entry("ext3_find_entry", 958 dir, de, bh, 959 (block<<EXT3_BLOCK_SIZE_BITS(sb)) 960 +((char *)de - bh->b_data))) { 961 brelse (bh); 962 goto errout; 963 } 964 *res_dir = de; 965 dx_release (frames); 966 return bh; 967 } 968 brelse (bh); 969 /* Check to see if we should continue to search */ 970 retval = ext3_htree_next_block(dir, hash, frame, 971 frames, NULL); 972 if (retval < 0) { 973 ext3_warning(sb, __FUNCTION__, 974 "error reading index page in directory #%lu", 975 dir->i_ino); 976 *err = retval; 977 goto errout; 978 } 979 } while (retval == 1); 980 981 *err = -ENOENT; 982errout: 983 dxtrace(printk("%s not found\n", name)); 984 dx_release (frames); 985 return NULL; 986} 987#endif 988 989static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) 990{ 991 struct inode * inode; 992 struct ext3_dir_entry_2 * de; 993 struct buffer_head * bh; 994 995 if (dentry->d_name.len > EXT3_NAME_LEN) 996 return ERR_PTR(-ENAMETOOLONG); 997 998 bh = ext3_find_entry(dentry, &de); 999 inode = NULL; 1000 if (bh) { 1001 unsigned long ino = le32_to_cpu(de->inode); 1002 brelse (bh); 1003 if (!ext3_valid_inum(dir->i_sb, ino)) { 1004 ext3_error(dir->i_sb, "ext3_lookup", 1005 "bad inode number: %lu", ino); 1006 inode = NULL; 1007 } else 1008 inode = iget(dir->i_sb, ino); 1009 1010 if (!inode) 1011 return ERR_PTR(-EACCES); 1012 } 1013 return d_splice_alias(inode, dentry); 1014} 1015 1016 1017struct dentry *ext3_get_parent(struct dentry *child) 1018{ 1019 unsigned long ino; 1020 struct dentry *parent; 1021 struct inode *inode; 1022 struct dentry dotdot; 1023 struct ext3_dir_entry_2 * de; 1024 struct buffer_head *bh; 1025 1026 dotdot.d_name.name = ".."; 1027 dotdot.d_name.len = 2; 1028 dotdot.d_parent = child; /* confusing, isn't it! */ 1029 1030 bh = ext3_find_entry(&dotdot, &de); 1031 inode = NULL; 1032 if (!bh) 1033 return ERR_PTR(-ENOENT); 1034 ino = le32_to_cpu(de->inode); 1035 brelse(bh); 1036 1037 if (!ext3_valid_inum(child->d_inode->i_sb, ino)) { 1038 ext3_error(child->d_inode->i_sb, "ext3_get_parent", 1039 "bad inode number: %lu", ino); 1040 inode = NULL; 1041 } else 1042 inode = iget(child->d_inode->i_sb, ino); 1043 1044 if (!inode) 1045 return ERR_PTR(-EACCES); 1046 1047 parent = d_alloc_anon(inode); 1048 if (!parent) { 1049 iput(inode); 1050 parent = ERR_PTR(-ENOMEM); 1051 } 1052 return parent; 1053} 1054 1055#define S_SHIFT 12 1056static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = { 1057 [S_IFREG >> S_SHIFT] = EXT3_FT_REG_FILE, 1058 [S_IFDIR >> S_SHIFT] = EXT3_FT_DIR, 1059 [S_IFCHR >> S_SHIFT] = EXT3_FT_CHRDEV, 1060 [S_IFBLK >> S_SHIFT] = EXT3_FT_BLKDEV, 1061 [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO, 1062 [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK, 1063 [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK, 1064}; 1065 1066static inline void ext3_set_de_type(struct super_block *sb, 1067 struct ext3_dir_entry_2 *de, 1068 umode_t mode) { 1069 if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE)) 1070 de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; 1071} 1072 1073#ifdef CONFIG_EXT3_INDEX 1074static struct ext3_dir_entry_2 * 1075dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) 1076{ 1077 unsigned rec_len = 0; 1078 1079 while (count--) { 1080 struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs); 1081 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1082 memcpy (to, de, rec_len); 1083 ((struct ext3_dir_entry_2 *) to)->rec_len = 1084 cpu_to_le16(rec_len); 1085 de->inode = 0; 1086 map++; 1087 to += rec_len; 1088 } 1089 return (struct ext3_dir_entry_2 *) (to - rec_len); 1090} 1091 1092static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size) 1093{ 1094 struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base; 1095 unsigned rec_len = 0; 1096 1097 prev = to = de; 1098 while ((char*)de < base + size) { 1099 next = (struct ext3_dir_entry_2 *) ((char *) de + 1100 le16_to_cpu(de->rec_len)); 1101 if (de->inode && de->name_len) { 1102 rec_len = EXT3_DIR_REC_LEN(de->name_len); 1103 if (de > to) 1104 memmove(to, de, rec_len); 1105 to->rec_len = cpu_to_le16(rec_len); 1106 prev = to; 1107 to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len); 1108 } 1109 de = next; 1110 } 1111 return prev; 1112} 1113 1114static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, 1115 struct buffer_head **bh,struct dx_frame *frame, 1116 struct dx_hash_info *hinfo, int *error) 1117{ 1118 unsigned blocksize = dir->i_sb->s_blocksize; 1119 unsigned count, continued; 1120 struct buffer_head *bh2; 1121 u32 newblock; 1122 u32 hash2; 1123 struct dx_map_entry *map; 1124 char *data1 = (*bh)->b_data, *data2; 1125 unsigned split; 1126 struct ext3_dir_entry_2 *de = NULL, *de2; 1127 int err; 1128 1129 bh2 = ext3_append (handle, dir, &newblock, error); 1130 if (!(bh2)) { 1131 brelse(*bh); 1132 *bh = NULL; 1133 goto errout; 1134 } 1135 1136 BUFFER_TRACE(*bh, "get_write_access"); 1137 err = ext3_journal_get_write_access(handle, *bh); 1138 if (err) { 1139 journal_error: 1140 brelse(*bh); 1141 brelse(bh2); 1142 *bh = NULL; 1143 ext3_std_error(dir->i_sb, err); 1144 goto errout; 1145 } 1146 BUFFER_TRACE(frame->bh, "get_write_access"); 1147 err = ext3_journal_get_write_access(handle, frame->bh); 1148 if (err) 1149 goto journal_error; 1150 1151 data2 = bh2->b_data; 1152 1153 /* create map in the end of data2 block */ 1154 map = (struct dx_map_entry *) (data2 + blocksize); 1155 count = dx_make_map ((struct ext3_dir_entry_2 *) data1, 1156 blocksize, hinfo, map); 1157 map -= count; 1158 split = count/2; // need to adjust to actual middle 1159 dx_sort_map (map, count); 1160 hash2 = map[split].hash; 1161 continued = hash2 == map[split - 1].hash; 1162 dxtrace(printk("Split block %i at %x, %i/%i\n", 1163 dx_get_block(frame->at), hash2, split, count-split)); 1164 1165 /* Fancy dance to stay within two buffers */ 1166 de2 = dx_move_dirents(data1, data2, map + split, count - split); 1167 de = dx_pack_dirents(data1,blocksize); 1168 de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de); 1169 de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2); 1170 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1)); 1171 dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1)); 1172 1173 /* Which block gets the new entry? */ 1174 if (hinfo->hash >= hash2) 1175 { 1176 swap(*bh, bh2); 1177 de = de2; 1178 } 1179 dx_insert_block (frame, hash2 + continued, newblock); 1180 err = ext3_journal_dirty_metadata (handle, bh2); 1181 if (err) 1182 goto journal_error; 1183 err = ext3_journal_dirty_metadata (handle, frame->bh); 1184 if (err) 1185 goto journal_error; 1186 brelse (bh2); 1187 dxtrace(dx_show_index ("frame", frame->entries)); 1188errout: 1189 return de; 1190} 1191#endif 1192 1193 1194/* 1195 * Add a new entry into a directory (leaf) block. If de is non-NULL, 1196 * it points to a directory entry which is guaranteed to be large 1197 * enough for new directory entry. If de is NULL, then 1198 * add_dirent_to_buf will attempt search the directory block for 1199 * space. It will return -ENOSPC if no space is available, and -EIO 1200 * and -EEXIST if directory entry already exists. 1201 * 1202 * NOTE! bh is NOT released in the case where ENOSPC is returned. In 1203 * all other cases bh is released. 1204 */ 1205static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, 1206 struct inode *inode, struct ext3_dir_entry_2 *de, 1207 struct buffer_head * bh) 1208{ 1209 struct inode *dir = dentry->d_parent->d_inode; 1210 const char *name = dentry->d_name.name; 1211 int namelen = dentry->d_name.len; 1212 unsigned long offset = 0; 1213 unsigned short reclen; 1214 int nlen, rlen, err; 1215 char *top; 1216 1217 reclen = EXT3_DIR_REC_LEN(namelen); 1218 if (!de) { 1219 de = (struct ext3_dir_entry_2 *)bh->b_data; 1220 top = bh->b_data + dir->i_sb->s_blocksize - reclen; 1221 while ((char *) de <= top) { 1222 if (!ext3_check_dir_entry("ext3_add_entry", dir, de, 1223 bh, offset)) { 1224 brelse (bh); 1225 return -EIO; 1226 } 1227 if (ext3_match (namelen, name, de)) { 1228 brelse (bh); 1229 return -EEXIST; 1230 } 1231 nlen = EXT3_DIR_REC_LEN(de->name_len); 1232 rlen = le16_to_cpu(de->rec_len); 1233 if ((de->inode? rlen - nlen: rlen) >= reclen) 1234 break; 1235 de = (struct ext3_dir_entry_2 *)((char *)de + rlen); 1236 offset += rlen; 1237 } 1238 if ((char *) de > top) 1239 return -ENOSPC; 1240 } 1241 BUFFER_TRACE(bh, "get_write_access"); 1242 err = ext3_journal_get_write_access(handle, bh); 1243 if (err) { 1244 ext3_std_error(dir->i_sb, err); 1245 brelse(bh); 1246 return err; 1247 } 1248 1249 /* By now the buffer is marked for journaling */ 1250 nlen = EXT3_DIR_REC_LEN(de->name_len); 1251 rlen = le16_to_cpu(de->rec_len); 1252 if (de->inode) { 1253 struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen); 1254 de1->rec_len = cpu_to_le16(rlen - nlen); 1255 de->rec_len = cpu_to_le16(nlen); 1256 de = de1; 1257 } 1258 de->file_type = EXT3_FT_UNKNOWN; 1259 if (inode) { 1260 de->inode = cpu_to_le32(inode->i_ino); 1261 ext3_set_de_type(dir->i_sb, de, inode->i_mode); 1262 } else 1263 de->inode = 0; 1264 de->name_len = namelen; 1265 memcpy (de->name, name, namelen); 1266 /* 1267 * XXX shouldn't update any times until successful 1268 * completion of syscall, but too many callers depend 1269 * on this. 1270 * 1271 * XXX similarly, too many callers depend on 1272 * ext3_new_inode() setting the times, but error 1273 * recovery deletes the inode, so the worst that can 1274 * happen is that the times are slightly out of date 1275 * and/or different from the directory change time. 1276 */ 1277 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; 1278 ext3_update_dx_flag(dir); 1279 dir->i_version++; 1280 ext3_mark_inode_dirty(handle, dir); 1281 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1282 err = ext3_journal_dirty_metadata(handle, bh); 1283 if (err) 1284 ext3_std_error(dir->i_sb, err); 1285 brelse(bh); 1286 return 0; 1287} 1288 1289#ifdef CONFIG_EXT3_INDEX 1290/* 1291 * This converts a one block unindexed directory to a 3 block indexed 1292 * directory, and adds the dentry to the indexed directory. 1293 */ 1294static int make_indexed_dir(handle_t *handle, struct dentry *dentry, 1295 struct inode *inode, struct buffer_head *bh) 1296{ 1297 struct inode *dir = dentry->d_parent->d_inode; 1298 const char *name = dentry->d_name.name; 1299 int namelen = dentry->d_name.len; 1300 struct buffer_head *bh2; 1301 struct dx_root *root; 1302 struct dx_frame frames[2], *frame; 1303 struct dx_entry *entries; 1304 struct ext3_dir_entry_2 *de, *de2; 1305 char *data1, *top; 1306 unsigned len; 1307 int retval; 1308 unsigned blocksize; 1309 struct dx_hash_info hinfo; 1310 u32 block; 1311 struct fake_dirent *fde; 1312 1313 blocksize = dir->i_sb->s_blocksize; 1314 dxtrace(printk("Creating index\n")); 1315 retval = ext3_journal_get_write_access(handle, bh); 1316 if (retval) { 1317 ext3_std_error(dir->i_sb, retval); 1318 brelse(bh); 1319 return retval; 1320 } 1321 root = (struct dx_root *) bh->b_data; 1322 1323 bh2 = ext3_append (handle, dir, &block, &retval); 1324 if (!(bh2)) { 1325 brelse(bh); 1326 return retval; 1327 } 1328 EXT3_I(dir)->i_flags |= EXT3_INDEX_FL; 1329 data1 = bh2->b_data; 1330 1331 /* The 0th block becomes the root, move the dirents out */ 1332 fde = &root->dotdot; 1333 de = (struct ext3_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len)); 1334 len = ((char *) root) + blocksize - (char *) de; 1335 memcpy (data1, de, len); 1336 de = (struct ext3_dir_entry_2 *) data1; 1337 top = data1 + len; 1338 while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top) 1339 de = de2; 1340 de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de); 1341 /* Initialize the root; the dot dirents already exist */ 1342 de = (struct ext3_dir_entry_2 *) (&root->dotdot); 1343 de->rec_len = cpu_to_le16(blocksize - EXT3_DIR_REC_LEN(2)); 1344 memset (&root->info, 0, sizeof(root->info)); 1345 root->info.info_length = sizeof(root->info); 1346 root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; 1347 entries = root->entries; 1348 dx_set_block (entries, 1); 1349 dx_set_count (entries, 1); 1350 dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info))); 1351 1352 /* Initialize as for dx_probe */ 1353 hinfo.hash_version = root->info.hash_version; 1354 hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; 1355 ext3fs_dirhash(name, namelen, &hinfo); 1356 frame = frames; 1357 frame->entries = entries; 1358 frame->at = entries; 1359 frame->bh = bh; 1360 bh = bh2; 1361 de = do_split(handle,dir, &bh, frame, &hinfo, &retval); 1362 dx_release (frames); 1363 if (!(de)) 1364 return retval; 1365 1366 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1367} 1368#endif 1369 1370/* 1371 * ext3_add_entry() 1372 * 1373 * adds a file entry to the specified directory, using the same 1374 * semantics as ext3_find_entry(). It returns NULL if it failed. 1375 * 1376 * NOTE!! The inode part of 'de' is left at 0 - which means you 1377 * may not sleep between calling this and putting something into 1378 * the entry, as someone else might have used it while you slept. 1379 */ 1380static int ext3_add_entry (handle_t *handle, struct dentry *dentry, 1381 struct inode *inode) 1382{ 1383 struct inode *dir = dentry->d_parent->d_inode; 1384 unsigned long offset; 1385 struct buffer_head * bh; 1386 struct ext3_dir_entry_2 *de; 1387 struct super_block * sb; 1388 int retval; 1389#ifdef CONFIG_EXT3_INDEX 1390 int dx_fallback=0; 1391#endif 1392 unsigned blocksize; 1393 u32 block, blocks; 1394 1395 sb = dir->i_sb; 1396 blocksize = sb->s_blocksize; 1397 if (!dentry->d_name.len) 1398 return -EINVAL; 1399#ifdef CONFIG_EXT3_INDEX 1400 if (is_dx(dir)) { 1401 retval = ext3_dx_add_entry(handle, dentry, inode); 1402 if (!retval || (retval != ERR_BAD_DX_DIR)) 1403 return retval; 1404 EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL; 1405 dx_fallback++; 1406 ext3_mark_inode_dirty(handle, dir); 1407 } 1408#endif 1409 blocks = dir->i_size >> sb->s_blocksize_bits; 1410 for (block = 0, offset = 0; block < blocks; block++) { 1411 bh = ext3_bread(handle, dir, block, 0, &retval); 1412 if(!bh) 1413 return retval; 1414 retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1415 if (retval != -ENOSPC) 1416 return retval; 1417 1418#ifdef CONFIG_EXT3_INDEX 1419 if (blocks == 1 && !dx_fallback && 1420 EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) 1421 return make_indexed_dir(handle, dentry, inode, bh); 1422#endif 1423 brelse(bh); 1424 } 1425 bh = ext3_append(handle, dir, &block, &retval); 1426 if (!bh) 1427 return retval; 1428 de = (struct ext3_dir_entry_2 *) bh->b_data; 1429 de->inode = 0; 1430 de->rec_len = cpu_to_le16(blocksize); 1431 return add_dirent_to_buf(handle, dentry, inode, de, bh); 1432} 1433 1434#ifdef CONFIG_EXT3_INDEX 1435/* 1436 * Returns 0 for success, or a negative error value 1437 */ 1438static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, 1439 struct inode *inode) 1440{ 1441 struct dx_frame frames[2], *frame; 1442 struct dx_entry *entries, *at; 1443 struct dx_hash_info hinfo; 1444 struct buffer_head * bh; 1445 struct inode *dir = dentry->d_parent->d_inode; 1446 struct super_block * sb = dir->i_sb; 1447 struct ext3_dir_entry_2 *de; 1448 int err; 1449 1450 frame = dx_probe(dentry, NULL, &hinfo, frames, &err); 1451 if (!frame) 1452 return err; 1453 entries = frame->entries; 1454 at = frame->at; 1455 1456 if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err))) 1457 goto cleanup; 1458 1459 BUFFER_TRACE(bh, "get_write_access"); 1460 err = ext3_journal_get_write_access(handle, bh); 1461 if (err) 1462 goto journal_error; 1463 1464 err = add_dirent_to_buf(handle, dentry, inode, NULL, bh); 1465 if (err != -ENOSPC) { 1466 bh = NULL; 1467 goto cleanup; 1468 } 1469 1470 /* Block full, should compress but for now just split */ 1471 dxtrace(printk("using %u of %u node entries\n", 1472 dx_get_count(entries), dx_get_limit(entries))); 1473 /* Need to split index? */ 1474 if (dx_get_count(entries) == dx_get_limit(entries)) { 1475 u32 newblock; 1476 unsigned icount = dx_get_count(entries); 1477 int levels = frame - frames; 1478 struct dx_entry *entries2; 1479 struct dx_node *node2; 1480 struct buffer_head *bh2; 1481 1482 if (levels && (dx_get_count(frames->entries) == 1483 dx_get_limit(frames->entries))) { 1484 ext3_warning(sb, __FUNCTION__, 1485 "Directory index full!"); 1486 err = -ENOSPC; 1487 goto cleanup; 1488 } 1489 bh2 = ext3_append (handle, dir, &newblock, &err); 1490 if (!(bh2)) 1491 goto cleanup; 1492 node2 = (struct dx_node *)(bh2->b_data); 1493 entries2 = node2->entries; 1494 node2->fake.rec_len = cpu_to_le16(sb->s_blocksize); 1495 node2->fake.inode = 0; 1496 BUFFER_TRACE(frame->bh, "get_write_access"); 1497 err = ext3_journal_get_write_access(handle, frame->bh); 1498 if (err) 1499 goto journal_error; 1500 if (levels) { 1501 unsigned icount1 = icount/2, icount2 = icount - icount1; 1502 unsigned hash2 = dx_get_hash(entries + icount1); 1503 dxtrace(printk("Split index %i/%i\n", icount1, icount2)); 1504 1505 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ 1506 err = ext3_journal_get_write_access(handle, 1507 frames[0].bh); 1508 if (err) 1509 goto journal_error; 1510 1511 memcpy ((char *) entries2, (char *) (entries + icount1), 1512 icount2 * sizeof(struct dx_entry)); 1513 dx_set_count (entries, icount1); 1514 dx_set_count (entries2, icount2); 1515 dx_set_limit (entries2, dx_node_limit(dir)); 1516 1517 /* Which index block gets the new entry? */ 1518 if (at - entries >= icount1) { 1519 frame->at = at = at - entries - icount1 + entries2; 1520 frame->entries = entries = entries2; 1521 swap(frame->bh, bh2); 1522 } 1523 dx_insert_block (frames + 0, hash2, newblock); 1524 dxtrace(dx_show_index ("node", frames[1].entries)); 1525 dxtrace(dx_show_index ("node", 1526 ((struct dx_node *) bh2->b_data)->entries)); 1527 err = ext3_journal_dirty_metadata(handle, bh2); 1528 if (err) 1529 goto journal_error; 1530 brelse (bh2); 1531 } else { 1532 dxtrace(printk("Creating second level index...\n")); 1533 memcpy((char *) entries2, (char *) entries, 1534 icount * sizeof(struct dx_entry)); 1535 dx_set_limit(entries2, dx_node_limit(dir)); 1536 1537 /* Set up root */ 1538 dx_set_count(entries, 1); 1539 dx_set_block(entries + 0, newblock); 1540 ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1; 1541 1542 /* Add new access path frame */ 1543 frame = frames + 1; 1544 frame->at = at = at - entries + entries2; 1545 frame->entries = entries = entries2; 1546 frame->bh = bh2; 1547 err = ext3_journal_get_write_access(handle, 1548 frame->bh); 1549 if (err) 1550 goto journal_error; 1551 } 1552 ext3_journal_dirty_metadata(handle, frames[0].bh); 1553 } 1554 de = do_split(handle, dir, &bh, frame, &hinfo, &err); 1555 if (!de) 1556 goto cleanup; 1557 err = add_dirent_to_buf(handle, dentry, inode, de, bh); 1558 bh = NULL; 1559 goto cleanup; 1560 1561journal_error: 1562 ext3_std_error(dir->i_sb, err); 1563cleanup: 1564 if (bh) 1565 brelse(bh); 1566 dx_release(frames); 1567 return err; 1568} 1569#endif 1570 1571/* 1572 * ext3_delete_entry deletes a directory entry by merging it with the 1573 * previous entry 1574 */ 1575static int ext3_delete_entry (handle_t *handle, 1576 struct inode * dir, 1577 struct ext3_dir_entry_2 * de_del, 1578 struct buffer_head * bh) 1579{ 1580 struct ext3_dir_entry_2 * de, * pde; 1581 int i; 1582 1583 i = 0; 1584 pde = NULL; 1585 de = (struct ext3_dir_entry_2 *) bh->b_data; 1586 while (i < bh->b_size) { 1587 if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i)) 1588 return -EIO; 1589 if (de == de_del) { 1590 BUFFER_TRACE(bh, "get_write_access"); 1591 ext3_journal_get_write_access(handle, bh); 1592 if (pde) 1593 pde->rec_len = 1594 cpu_to_le16(le16_to_cpu(pde->rec_len) + 1595 le16_to_cpu(de->rec_len)); 1596 else 1597 de->inode = 0; 1598 dir->i_version++; 1599 BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); 1600 ext3_journal_dirty_metadata(handle, bh); 1601 return 0; 1602 } 1603 i += le16_to_cpu(de->rec_len); 1604 pde = de; 1605 de = (struct ext3_dir_entry_2 *) 1606 ((char *) de + le16_to_cpu(de->rec_len)); 1607 } 1608 return -ENOENT; 1609} 1610 1611/* 1612 * ext3_mark_inode_dirty is somewhat expensive, so unlike ext2 we 1613 * do not perform it in these functions. We perform it at the call site, 1614 * if it is needed. 1615 */ 1616static inline void ext3_inc_count(handle_t *handle, struct inode *inode) 1617{ 1618 inode->i_nlink++; 1619} 1620 1621static inline void ext3_dec_count(handle_t *handle, struct inode *inode) 1622{ 1623 inode->i_nlink--; 1624} 1625 1626static int ext3_add_nondir(handle_t *handle, 1627 struct dentry *dentry, struct inode *inode) 1628{ 1629 int err = ext3_add_entry(handle, dentry, inode); 1630 if (!err) { 1631 ext3_mark_inode_dirty(handle, inode); 1632 d_instantiate(dentry, inode); 1633 return 0; 1634 } 1635 ext3_dec_count(handle, inode); 1636 iput(inode); 1637 return err; 1638} 1639 1640/* 1641 * By the time this is called, we already have created 1642 * the directory cache entry for the new file, but it 1643 * is so far negative - it has no inode. 1644 * 1645 * If the create succeeds, we fill in the inode information 1646 * with d_instantiate(). 1647 */ 1648static int ext3_create (struct inode * dir, struct dentry * dentry, int mode, 1649 struct nameidata *nd) 1650{ 1651 handle_t *handle; 1652 struct inode * inode; 1653 int err, retries = 0; 1654 1655retry: 1656 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1657 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1658 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1659 if (IS_ERR(handle)) 1660 return PTR_ERR(handle); 1661 1662 if (IS_DIRSYNC(dir)) 1663 handle->h_sync = 1; 1664 1665 inode = ext3_new_inode (handle, dir, mode); 1666 err = PTR_ERR(inode); 1667 if (!IS_ERR(inode)) { 1668 inode->i_op = &ext3_file_inode_operations; 1669 inode->i_fop = &ext3_file_operations; 1670 ext3_set_aops(inode); 1671 err = ext3_add_nondir(handle, dentry, inode); 1672 } 1673 ext3_journal_stop(handle); 1674 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1675 goto retry; 1676 return err; 1677} 1678 1679static int ext3_mknod (struct inode * dir, struct dentry *dentry, 1680 int mode, dev_t rdev) 1681{ 1682 handle_t *handle; 1683 struct inode *inode; 1684 int err, retries = 0; 1685 1686 if (!new_valid_dev(rdev)) 1687 return -EINVAL; 1688 1689retry: 1690 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1691 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1692 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1693 if (IS_ERR(handle)) 1694 return PTR_ERR(handle); 1695 1696 if (IS_DIRSYNC(dir)) 1697 handle->h_sync = 1; 1698 1699 inode = ext3_new_inode (handle, dir, mode); 1700 err = PTR_ERR(inode); 1701 if (!IS_ERR(inode)) { 1702 init_special_inode(inode, inode->i_mode, rdev); 1703#ifdef CONFIG_EXT3_FS_XATTR 1704 inode->i_op = &ext3_special_inode_operations; 1705#endif 1706 err = ext3_add_nondir(handle, dentry, inode); 1707 } 1708 ext3_journal_stop(handle); 1709 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1710 goto retry; 1711 return err; 1712} 1713 1714static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode) 1715{ 1716 handle_t *handle; 1717 struct inode * inode; 1718 struct buffer_head * dir_block; 1719 struct ext3_dir_entry_2 * de; 1720 int err, retries = 0; 1721 1722 if (dir->i_nlink >= EXT3_LINK_MAX) 1723 return -EMLINK; 1724 1725retry: 1726 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 1727 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 1728 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 1729 if (IS_ERR(handle)) 1730 return PTR_ERR(handle); 1731 1732 if (IS_DIRSYNC(dir)) 1733 handle->h_sync = 1; 1734 1735 inode = ext3_new_inode (handle, dir, S_IFDIR | mode); 1736 err = PTR_ERR(inode); 1737 if (IS_ERR(inode)) 1738 goto out_stop; 1739 1740 inode->i_op = &ext3_dir_inode_operations; 1741 inode->i_fop = &ext3_dir_operations; 1742 inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize; 1743 dir_block = ext3_bread (handle, inode, 0, 1, &err); 1744 if (!dir_block) { 1745 inode->i_nlink--; /* is this nlink == 0? */ 1746 ext3_mark_inode_dirty(handle, inode); 1747 iput (inode); 1748 goto out_stop; 1749 } 1750 BUFFER_TRACE(dir_block, "get_write_access"); 1751 ext3_journal_get_write_access(handle, dir_block); 1752 de = (struct ext3_dir_entry_2 *) dir_block->b_data; 1753 de->inode = cpu_to_le32(inode->i_ino); 1754 de->name_len = 1; 1755 de->rec_len = cpu_to_le16(EXT3_DIR_REC_LEN(de->name_len)); 1756 strcpy (de->name, "."); 1757 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1758 de = (struct ext3_dir_entry_2 *) 1759 ((char *) de + le16_to_cpu(de->rec_len)); 1760 de->inode = cpu_to_le32(dir->i_ino); 1761 de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT3_DIR_REC_LEN(1)); 1762 de->name_len = 2; 1763 strcpy (de->name, ".."); 1764 ext3_set_de_type(dir->i_sb, de, S_IFDIR); 1765 inode->i_nlink = 2; 1766 BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata"); 1767 ext3_journal_dirty_metadata(handle, dir_block); 1768 brelse (dir_block); 1769 ext3_mark_inode_dirty(handle, inode); 1770 err = ext3_add_entry (handle, dentry, inode); 1771 if (err) { 1772 inode->i_nlink = 0; 1773 ext3_mark_inode_dirty(handle, inode); 1774 iput (inode); 1775 goto out_stop; 1776 } 1777 dir->i_nlink++; 1778 ext3_update_dx_flag(dir); 1779 ext3_mark_inode_dirty(handle, dir); 1780 d_instantiate(dentry, inode); 1781out_stop: 1782 ext3_journal_stop(handle); 1783 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 1784 goto retry; 1785 return err; 1786} 1787 1788/* 1789 * routine to check that the specified directory is empty (for rmdir) 1790 */ 1791static int empty_dir (struct inode * inode) 1792{ 1793 unsigned long offset; 1794 struct buffer_head * bh; 1795 struct ext3_dir_entry_2 * de, * de1; 1796 struct super_block * sb; 1797 int err = 0; 1798 1799 sb = inode->i_sb; 1800 if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) || 1801 !(bh = ext3_bread (NULL, inode, 0, 0, &err))) { 1802 if (err) 1803 ext3_error(inode->i_sb, __FUNCTION__, 1804 "error %d reading directory #%lu offset 0", 1805 err, inode->i_ino); 1806 else 1807 ext3_warning(inode->i_sb, __FUNCTION__, 1808 "bad directory (dir #%lu) - no data block", 1809 inode->i_ino); 1810 return 1; 1811 } 1812 de = (struct ext3_dir_entry_2 *) bh->b_data; 1813 de1 = (struct ext3_dir_entry_2 *) 1814 ((char *) de + le16_to_cpu(de->rec_len)); 1815 if (le32_to_cpu(de->inode) != inode->i_ino || 1816 !le32_to_cpu(de1->inode) || 1817 strcmp (".", de->name) || 1818 strcmp ("..", de1->name)) { 1819 ext3_warning (inode->i_sb, "empty_dir", 1820 "bad directory (dir #%lu) - no `.' or `..'", 1821 inode->i_ino); 1822 brelse (bh); 1823 return 1; 1824 } 1825 offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len); 1826 de = (struct ext3_dir_entry_2 *) 1827 ((char *) de1 + le16_to_cpu(de1->rec_len)); 1828 while (offset < inode->i_size ) { 1829 if (!bh || 1830 (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { 1831 err = 0; 1832 brelse (bh); 1833 bh = ext3_bread (NULL, inode, 1834 offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err); 1835 if (!bh) { 1836 if (err) 1837 ext3_error(sb, __FUNCTION__, 1838 "error %d reading directory" 1839 " #%lu offset %lu", 1840 err, inode->i_ino, offset); 1841 offset += sb->s_blocksize; 1842 continue; 1843 } 1844 de = (struct ext3_dir_entry_2 *) bh->b_data; 1845 } 1846 if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) { 1847 de = (struct ext3_dir_entry_2 *)(bh->b_data + 1848 sb->s_blocksize); 1849 offset = (offset | (sb->s_blocksize - 1)) + 1; 1850 continue; 1851 } 1852 if (le32_to_cpu(de->inode)) { 1853 brelse (bh); 1854 return 0; 1855 } 1856 offset += le16_to_cpu(de->rec_len); 1857 de = (struct ext3_dir_entry_2 *) 1858 ((char *) de + le16_to_cpu(de->rec_len)); 1859 } 1860 brelse (bh); 1861 return 1; 1862} 1863 1864/* ext3_orphan_add() links an unlinked or truncated inode into a list of 1865 * such inodes, starting at the superblock, in case we crash before the 1866 * file is closed/deleted, or in case the inode truncate spans multiple 1867 * transactions and the last transaction is not recovered after a crash. 1868 * 1869 * At filesystem recovery time, we walk this list deleting unlinked 1870 * inodes and truncating linked inodes in ext3_orphan_cleanup(). 1871 */ 1872int ext3_orphan_add(handle_t *handle, struct inode *inode) 1873{ 1874 struct super_block *sb = inode->i_sb; 1875 struct ext3_iloc iloc; 1876 int err = 0, rc; 1877 1878 lock_super(sb); 1879 if (!list_empty(&EXT3_I(inode)->i_orphan)) 1880 goto out_unlock; 1881 1882 /* Orphan handling is only valid for files with data blocks 1883 * being truncated, or files being unlinked. */ 1884 1885 /* @@@ FIXME: Observation from aviro: 1886 * I think I can trigger J_ASSERT in ext3_orphan_add(). We block 1887 * here (on lock_super()), so race with ext3_link() which might bump 1888 * ->i_nlink. For, say it, character device. Not a regular file, 1889 * not a directory, not a symlink and ->i_nlink > 0. 1890 */ 1891 J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 1892 S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); 1893 1894 BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access"); 1895 err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh); 1896 if (err) 1897 goto out_unlock; 1898 1899 err = ext3_reserve_inode_write(handle, inode, &iloc); 1900 if (err) 1901 goto out_unlock; 1902 1903 /* Insert this inode at the head of the on-disk orphan list... */ 1904 NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan); 1905 EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); 1906 err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh); 1907 rc = ext3_mark_iloc_dirty(handle, inode, &iloc); 1908 if (!err) 1909 err = rc; 1910 1911 /* Only add to the head of the in-memory list if all the 1912 * previous operations succeeded. If the orphan_add is going to 1913 * fail (possibly taking the journal offline), we can't risk 1914 * leaving the inode on the orphan list: stray orphan-list 1915 * entries can cause panics at unmount time. 1916 * 1917 * This is safe: on error we're going to ignore the orphan list 1918 * anyway on the next recovery. */ 1919 if (!err) 1920 list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan); 1921 1922 jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); 1923 jbd_debug(4, "orphan inode %lu will point to %d\n", 1924 inode->i_ino, NEXT_ORPHAN(inode)); 1925out_unlock: 1926 unlock_super(sb); 1927 ext3_std_error(inode->i_sb, err); 1928 return err; 1929} 1930 1931/* 1932 * ext3_orphan_del() removes an unlinked or truncated inode from the list 1933 * of such inodes stored on disk, because it is finally being cleaned up. 1934 */ 1935int ext3_orphan_del(handle_t *handle, struct inode *inode) 1936{ 1937 struct list_head *prev; 1938 struct ext3_inode_info *ei = EXT3_I(inode); 1939 struct ext3_sb_info *sbi; 1940 unsigned long ino_next; 1941 struct ext3_iloc iloc; 1942 int err = 0; 1943 1944 lock_super(inode->i_sb); 1945 if (list_empty(&ei->i_orphan)) { 1946 unlock_super(inode->i_sb); 1947 return 0; 1948 } 1949 1950 ino_next = NEXT_ORPHAN(inode); 1951 prev = ei->i_orphan.prev; 1952 sbi = EXT3_SB(inode->i_sb); 1953 1954 jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); 1955 1956 list_del_init(&ei->i_orphan); 1957 1958 /* If we're on an error path, we may not have a valid 1959 * transaction handle with which to update the orphan list on 1960 * disk, but we still need to remove the inode from the linked 1961 * list in memory. */ 1962 if (!handle) 1963 goto out; 1964 1965 err = ext3_reserve_inode_write(handle, inode, &iloc); 1966 if (err) 1967 goto out_err; 1968 1969 if (prev == &sbi->s_orphan) { 1970 jbd_debug(4, "superblock will point to %lu\n", ino_next); 1971 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 1972 err = ext3_journal_get_write_access(handle, sbi->s_sbh); 1973 if (err) 1974 goto out_brelse; 1975 sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); 1976 err = ext3_journal_dirty_metadata(handle, sbi->s_sbh); 1977 } else { 1978 struct ext3_iloc iloc2; 1979 struct inode *i_prev = 1980 &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode; 1981 1982 jbd_debug(4, "orphan inode %lu will point to %lu\n", 1983 i_prev->i_ino, ino_next); 1984 err = ext3_reserve_inode_write(handle, i_prev, &iloc2); 1985 if (err) 1986 goto out_brelse; 1987 NEXT_ORPHAN(i_prev) = ino_next; 1988 err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2); 1989 } 1990 if (err) 1991 goto out_brelse; 1992 NEXT_ORPHAN(inode) = 0; 1993 err = ext3_mark_iloc_dirty(handle, inode, &iloc); 1994 1995out_err: 1996 ext3_std_error(inode->i_sb, err); 1997out: 1998 unlock_super(inode->i_sb); 1999 return err; 2000 2001out_brelse: 2002 brelse(iloc.bh); 2003 goto out_err; 2004} 2005 2006static int ext3_rmdir (struct inode * dir, struct dentry *dentry) 2007{ 2008 int retval; 2009 struct inode * inode; 2010 struct buffer_head * bh; 2011 struct ext3_dir_entry_2 * de; 2012 handle_t *handle; 2013 2014 /* Initialize quotas before so that eventual writes go in 2015 * separate transaction */ 2016 DQUOT_INIT(dentry->d_inode); 2017 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2018 if (IS_ERR(handle)) 2019 return PTR_ERR(handle); 2020 2021 retval = -ENOENT; 2022 bh = ext3_find_entry (dentry, &de); 2023 if (!bh) 2024 goto end_rmdir; 2025 2026 if (IS_DIRSYNC(dir)) 2027 handle->h_sync = 1; 2028 2029 inode = dentry->d_inode; 2030 2031 retval = -EIO; 2032 if (le32_to_cpu(de->inode) != inode->i_ino) 2033 goto end_rmdir; 2034 2035 retval = -ENOTEMPTY; 2036 if (!empty_dir (inode)) 2037 goto end_rmdir; 2038 2039 retval = ext3_delete_entry(handle, dir, de, bh); 2040 if (retval) 2041 goto end_rmdir; 2042 if (inode->i_nlink != 2) 2043 ext3_warning (inode->i_sb, "ext3_rmdir", 2044 "empty directory has nlink!=2 (%d)", 2045 inode->i_nlink); 2046 inode->i_version++; 2047 inode->i_nlink = 0; 2048 /* There's no need to set i_disksize: the fact that i_nlink is 2049 * zero will ensure that the right thing happens during any 2050 * recovery. */ 2051 inode->i_size = 0; 2052 ext3_orphan_add(handle, inode); 2053 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2054 ext3_mark_inode_dirty(handle, inode); 2055 dir->i_nlink--; 2056 ext3_update_dx_flag(dir); 2057 ext3_mark_inode_dirty(handle, dir); 2058 2059end_rmdir: 2060 ext3_journal_stop(handle); 2061 brelse (bh); 2062 return retval; 2063} 2064 2065static int ext3_unlink(struct inode * dir, struct dentry *dentry) 2066{ 2067 int retval; 2068 struct inode * inode; 2069 struct buffer_head * bh; 2070 struct ext3_dir_entry_2 * de; 2071 handle_t *handle; 2072 2073 /* Initialize quotas before so that eventual writes go 2074 * in separate transaction */ 2075 DQUOT_INIT(dentry->d_inode); 2076 handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); 2077 if (IS_ERR(handle)) 2078 return PTR_ERR(handle); 2079 2080 if (IS_DIRSYNC(dir)) 2081 handle->h_sync = 1; 2082 2083 retval = -ENOENT; 2084 bh = ext3_find_entry (dentry, &de); 2085 if (!bh) 2086 goto end_unlink; 2087 2088 inode = dentry->d_inode; 2089 2090 retval = -EIO; 2091 if (le32_to_cpu(de->inode) != inode->i_ino) 2092 goto end_unlink; 2093 2094 if (!inode->i_nlink) { 2095 ext3_warning (inode->i_sb, "ext3_unlink", 2096 "Deleting nonexistent file (%lu), %d", 2097 inode->i_ino, inode->i_nlink); 2098 inode->i_nlink = 1; 2099 } 2100 retval = ext3_delete_entry(handle, dir, de, bh); 2101 if (retval) 2102 goto end_unlink; 2103 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; 2104 ext3_update_dx_flag(dir); 2105 ext3_mark_inode_dirty(handle, dir); 2106 inode->i_nlink--; 2107 if (!inode->i_nlink) 2108 ext3_orphan_add(handle, inode); 2109 inode->i_ctime = dir->i_ctime; 2110 ext3_mark_inode_dirty(handle, inode); 2111 retval = 0; 2112 2113end_unlink: 2114 ext3_journal_stop(handle); 2115 brelse (bh); 2116 return retval; 2117} 2118 2119static int ext3_symlink (struct inode * dir, 2120 struct dentry *dentry, const char * symname) 2121{ 2122 handle_t *handle; 2123 struct inode * inode; 2124 int l, err, retries = 0; 2125 2126 l = strlen(symname)+1; 2127 if (l > dir->i_sb->s_blocksize) 2128 return -ENAMETOOLONG; 2129 2130retry: 2131 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2132 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 5 + 2133 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); 2134 if (IS_ERR(handle)) 2135 return PTR_ERR(handle); 2136 2137 if (IS_DIRSYNC(dir)) 2138 handle->h_sync = 1; 2139 2140 inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO); 2141 err = PTR_ERR(inode); 2142 if (IS_ERR(inode)) 2143 goto out_stop; 2144 2145 if (l > sizeof (EXT3_I(inode)->i_data)) { 2146 inode->i_op = &ext3_symlink_inode_operations; 2147 ext3_set_aops(inode); 2148 /* 2149 * page_symlink() calls into ext3_prepare/commit_write. 2150 * We have a transaction open. All is sweetness. It also sets 2151 * i_size in generic_commit_write(). 2152 */ 2153 err = __page_symlink(inode, symname, l, 2154 mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS); 2155 if (err) { 2156 ext3_dec_count(handle, inode); 2157 ext3_mark_inode_dirty(handle, inode); 2158 iput (inode); 2159 goto out_stop; 2160 } 2161 } else { 2162 inode->i_op = &ext3_fast_symlink_inode_operations; 2163 memcpy((char*)&EXT3_I(inode)->i_data,symname,l); 2164 inode->i_size = l-1; 2165 } 2166 EXT3_I(inode)->i_disksize = inode->i_size; 2167 err = ext3_add_nondir(handle, dentry, inode); 2168out_stop: 2169 ext3_journal_stop(handle); 2170 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2171 goto retry; 2172 return err; 2173} 2174 2175static int ext3_link (struct dentry * old_dentry, 2176 struct inode * dir, struct dentry *dentry) 2177{ 2178 handle_t *handle; 2179 struct inode *inode = old_dentry->d_inode; 2180 int err, retries = 0; 2181 2182 if (inode->i_nlink >= EXT3_LINK_MAX) 2183 return -EMLINK; 2184 2185retry: 2186 handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + 2187 EXT3_INDEX_EXTRA_TRANS_BLOCKS); 2188 if (IS_ERR(handle)) 2189 return PTR_ERR(handle); 2190 2191 if (IS_DIRSYNC(dir)) 2192 handle->h_sync = 1; 2193 2194 inode->i_ctime = CURRENT_TIME_SEC; 2195 ext3_inc_count(handle, inode); 2196 atomic_inc(&inode->i_count); 2197 2198 err = ext3_add_nondir(handle, dentry, inode); 2199 ext3_journal_stop(handle); 2200 if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) 2201 goto retry; 2202 return err; 2203} 2204 2205#define PARENT_INO(buffer) \ 2206 ((struct ext3_dir_entry_2 *) ((char *) buffer + \ 2207 le16_to_cpu(((struct ext3_dir_entry_2 *) buffer)->rec_len)))->inode 2208 2209/* 2210 * Anybody can rename anything with this: the permission checks are left to the 2211 * higher-level routines. 2212 */ 2213static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, 2214 struct inode * new_dir,struct dentry *new_dentry) 2215{ 2216 handle_t *handle; 2217 struct inode * old_inode, * new_inode; 2218 struct buffer_head * old_bh, * new_bh, * dir_bh; 2219 struct ext3_dir_entry_2 * old_de, * new_de; 2220 int retval; 2221 2222 old_bh = new_bh = dir_bh = NULL; 2223 2224 /* Initialize quotas before so that eventual writes go 2225 * in separate transaction */ 2226 if (new_dentry->d_inode) 2227 DQUOT_INIT(new_dentry->d_inode); 2228 handle = ext3_journal_start(old_dir, 2 * 2229 EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) + 2230 EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2); 2231 if (IS_ERR(handle)) 2232 return PTR_ERR(handle); 2233 2234 if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) 2235 handle->h_sync = 1; 2236 2237 old_bh = ext3_find_entry (old_dentry, &old_de); 2238 /* 2239 * Check for inode number is _not_ due to possible IO errors. 2240 * We might rmdir the source, keep it as pwd of some process 2241 * and merrily kill the link to whatever was created under the 2242 * same name. Goodbye sticky bit ;-< 2243 */ 2244 old_inode = old_dentry->d_inode; 2245 retval = -ENOENT; 2246 if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino) 2247 goto end_rename; 2248 2249 new_inode = new_dentry->d_inode; 2250 new_bh = ext3_find_entry (new_dentry, &new_de); 2251 if (new_bh) { 2252 if (!new_inode) { 2253 brelse (new_bh); 2254 new_bh = NULL; 2255 } 2256 } 2257 if (S_ISDIR(old_inode->i_mode)) { 2258 if (new_inode) { 2259 retval = -ENOTEMPTY; 2260 if (!empty_dir (new_inode)) 2261 goto end_rename; 2262 } 2263 retval = -EIO; 2264 dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval); 2265 if (!dir_bh) 2266 goto end_rename; 2267 if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino) 2268 goto end_rename; 2269 retval = -EMLINK; 2270 if (!new_inode && new_dir!=old_dir && 2271 new_dir->i_nlink >= EXT3_LINK_MAX) 2272 goto end_rename; 2273 } 2274 if (!new_bh) { 2275 retval = ext3_add_entry (handle, new_dentry, old_inode); 2276 if (retval) 2277 goto end_rename; 2278 } else { 2279 BUFFER_TRACE(new_bh, "get write access"); 2280 ext3_journal_get_write_access(handle, new_bh); 2281 new_de->inode = cpu_to_le32(old_inode->i_ino); 2282 if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb, 2283 EXT3_FEATURE_INCOMPAT_FILETYPE)) 2284 new_de->file_type = old_de->file_type; 2285 new_dir->i_version++; 2286 BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata"); 2287 ext3_journal_dirty_metadata(handle, new_bh); 2288 brelse(new_bh); 2289 new_bh = NULL; 2290 } 2291 2292 /* 2293 * Like most other Unix systems, set the ctime for inodes on a 2294 * rename. 2295 */ 2296 old_inode->i_ctime = CURRENT_TIME_SEC; 2297 ext3_mark_inode_dirty(handle, old_inode); 2298 2299 /* 2300 * ok, that's it 2301 */ 2302 if (le32_to_cpu(old_de->inode) != old_inode->i_ino || 2303 old_de->name_len != old_dentry->d_name.len || 2304 strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) || 2305 (retval = ext3_delete_entry(handle, old_dir, 2306 old_de, old_bh)) == -ENOENT) { 2307 /* old_de could have moved from under us during htree split, so 2308 * make sure that we are deleting the right entry. We might 2309 * also be pointing to a stale entry in the unused part of 2310 * old_bh so just checking inum and the name isn't enough. */ 2311 struct buffer_head *old_bh2; 2312 struct ext3_dir_entry_2 *old_de2; 2313 2314 old_bh2 = ext3_find_entry(old_dentry, &old_de2); 2315 if (old_bh2) { 2316 retval = ext3_delete_entry(handle, old_dir, 2317 old_de2, old_bh2); 2318 brelse(old_bh2); 2319 } 2320 } 2321 if (retval) { 2322 ext3_warning(old_dir->i_sb, "ext3_rename", 2323 "Deleting old file (%lu), %d, error=%d", 2324 old_dir->i_ino, old_dir->i_nlink, retval); 2325 } 2326 2327 if (new_inode) { 2328 new_inode->i_nlink--; 2329 new_inode->i_ctime = CURRENT_TIME_SEC; 2330 } 2331 old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; 2332 ext3_update_dx_flag(old_dir); 2333 if (dir_bh) { 2334 BUFFER_TRACE(dir_bh, "get_write_access"); 2335 ext3_journal_get_write_access(handle, dir_bh); 2336 PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino); 2337 BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata"); 2338 ext3_journal_dirty_metadata(handle, dir_bh); 2339 old_dir->i_nlink--; 2340 if (new_inode) { 2341 new_inode->i_nlink--; 2342 } else { 2343 new_dir->i_nlink++; 2344 ext3_update_dx_flag(new_dir); 2345 ext3_mark_inode_dirty(handle, new_dir); 2346 } 2347 } 2348 ext3_mark_inode_dirty(handle, old_dir); 2349 if (new_inode) { 2350 ext3_mark_inode_dirty(handle, new_inode); 2351 if (!new_inode->i_nlink) 2352 ext3_orphan_add(handle, new_inode); 2353 } 2354 retval = 0; 2355 2356end_rename: 2357 brelse (dir_bh); 2358 brelse (old_bh); 2359 brelse (new_bh); 2360 ext3_journal_stop(handle); 2361 return retval; 2362} 2363 2364/* 2365 * directories can handle most operations... 2366 */ 2367struct inode_operations ext3_dir_inode_operations = { 2368 .create = ext3_create, 2369 .lookup = ext3_lookup, 2370 .link = ext3_link, 2371 .unlink = ext3_unlink, 2372 .symlink = ext3_symlink, 2373 .mkdir = ext3_mkdir, 2374 .rmdir = ext3_rmdir, 2375 .mknod = ext3_mknod, 2376 .rename = ext3_rename, 2377 .setattr = ext3_setattr, 2378#ifdef CONFIG_EXT3_FS_XATTR 2379 .setxattr = generic_setxattr, 2380 .getxattr = generic_getxattr, 2381 .listxattr = ext3_listxattr, 2382 .removexattr = generic_removexattr, 2383#endif 2384 .permission = ext3_permission, 2385}; 2386 2387struct inode_operations ext3_special_inode_operations = { 2388 .setattr = ext3_setattr, 2389#ifdef CONFIG_EXT3_FS_XATTR 2390 .setxattr = generic_setxattr, 2391 .getxattr = generic_getxattr, 2392 .listxattr = ext3_listxattr, 2393 .removexattr = generic_removexattr, 2394#endif 2395 .permission = ext3_permission, 2396}; 2397