1 /* 2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README 3 */ 4 5 /* 6 * Written by Anatoly P. Pinchuk pap@namesys.botik.ru 7 * Programm System Institute 8 * Pereslavl-Zalessky Russia 9 */ 10 11 /* 12 * This file contains functions dealing with S+tree 13 * 14 * B_IS_IN_TREE 15 * copy_item_head 16 * comp_short_keys 17 * comp_keys 18 * comp_short_le_keys 19 * le_key2cpu_key 20 * comp_le_keys 21 * bin_search 22 * get_lkey 23 * get_rkey 24 * key_in_buffer 25 * decrement_bcount 26 * decrement_counters_in_path 27 * reiserfs_check_path 28 * pathrelse_and_restore 29 * pathrelse 30 * search_by_key_reada 31 * search_by_key 32 * search_for_position_by_key 33 * comp_items 34 * prepare_for_direct_item 35 * prepare_for_direntry_item 36 * prepare_for_delete_or_cut 37 * calc_deleted_bytes_number 38 * init_tb_struct 39 * padd_item 40 * reiserfs_delete_item 41 * reiserfs_delete_solid_item 42 * reiserfs_delete_object 43 * maybe_indirect_to_direct 44 * indirect_to_direct_roll_back 45 * reiserfs_cut_from_item 46 * truncate_directory 47 * reiserfs_do_truncate 48 * reiserfs_paste_into_item 49 * reiserfs_insert_item 50 */ 51 52 #include <linux/time.h> 53 #include <linux/string.h> 54 #include <linux/pagemap.h> 55 #include <linux/reiserfs_fs.h> 56 #include <linux/buffer_head.h> 57 #include <linux/quotaops.h> 58 59 /* Does the buffer contain a disk block which is in the tree. */ 60 inline int B_IS_IN_TREE(const struct buffer_head *p_s_bh) 61 { 62 63 RFALSE(B_LEVEL(p_s_bh) > MAX_HEIGHT, 64 "PAP-1010: block (%b) has too big level (%z)", p_s_bh, p_s_bh); 65 66 return (B_LEVEL(p_s_bh) != FREE_LEVEL); 67 } 68 69 // 70 // to gets item head in le form 71 // 72 inline void copy_item_head(struct item_head *p_v_to, 73 const struct item_head *p_v_from) 74 { 75 memcpy(p_v_to, p_v_from, IH_SIZE); 76 } 77 78 /* k1 is pointer to on-disk structure which is stored in little-endian 79 form. k2 is pointer to cpu variable. For key of items of the same 80 object this returns 0. 81 Returns: -1 if key1 < key2 82 0 if key1 == key2 83 1 if key1 > key2 */ 84 inline int comp_short_keys(const struct reiserfs_key *le_key, 85 const struct cpu_key *cpu_key) 86 { 87 __u32 n; 88 n = le32_to_cpu(le_key->k_dir_id); 89 if (n < cpu_key->on_disk_key.k_dir_id) 90 return -1; 91 if (n > cpu_key->on_disk_key.k_dir_id) 92 return 1; 93 n = le32_to_cpu(le_key->k_objectid); 94 if (n < cpu_key->on_disk_key.k_objectid) 95 return -1; 96 if (n > cpu_key->on_disk_key.k_objectid) 97 return 1; 98 return 0; 99 } 100 101 /* k1 is pointer to on-disk structure which is stored in little-endian 102 form. k2 is pointer to cpu variable. 103 Compare keys using all 4 key fields. 104 Returns: -1 if key1 < key2 0 105 if key1 = key2 1 if key1 > key2 */ 106 static inline int comp_keys(const struct reiserfs_key *le_key, 107 const struct cpu_key *cpu_key) 108 { 109 int retval; 110 111 retval = comp_short_keys(le_key, cpu_key); 112 if (retval) 113 return retval; 114 if (le_key_k_offset(le_key_version(le_key), le_key) < 115 cpu_key_k_offset(cpu_key)) 116 return -1; 117 if (le_key_k_offset(le_key_version(le_key), le_key) > 118 cpu_key_k_offset(cpu_key)) 119 return 1; 120 121 if (cpu_key->key_length == 3) 122 return 0; 123 124 /* this part is needed only when tail conversion is in progress */ 125 if (le_key_k_type(le_key_version(le_key), le_key) < 126 cpu_key_k_type(cpu_key)) 127 return -1; 128 129 if (le_key_k_type(le_key_version(le_key), le_key) > 130 cpu_key_k_type(cpu_key)) 131 return 1; 132 133 return 0; 134 } 135 136 inline int comp_short_le_keys(const struct reiserfs_key *key1, 137 const struct reiserfs_key *key2) 138 { 139 __u32 *p_s_1_u32, *p_s_2_u32; 140 int n_key_length = REISERFS_SHORT_KEY_LEN; 141 142 p_s_1_u32 = (__u32 *) key1; 143 p_s_2_u32 = (__u32 *) key2; 144 for (; n_key_length--; ++p_s_1_u32, ++p_s_2_u32) { 145 if (le32_to_cpu(*p_s_1_u32) < le32_to_cpu(*p_s_2_u32)) 146 return -1; 147 if (le32_to_cpu(*p_s_1_u32) > le32_to_cpu(*p_s_2_u32)) 148 return 1; 149 } 150 return 0; 151 } 152 153 inline void le_key2cpu_key(struct cpu_key *to, const struct reiserfs_key *from) 154 { 155 int version; 156 to->on_disk_key.k_dir_id = le32_to_cpu(from->k_dir_id); 157 to->on_disk_key.k_objectid = le32_to_cpu(from->k_objectid); 158 159 // find out version of the key 160 version = le_key_version(from); 161 to->version = version; 162 to->on_disk_key.k_offset = le_key_k_offset(version, from); 163 to->on_disk_key.k_type = le_key_k_type(version, from); 164 } 165 166 // this does not say which one is bigger, it only returns 1 if keys 167 // are not equal, 0 otherwise 168 inline int comp_le_keys(const struct reiserfs_key *k1, 169 const struct reiserfs_key *k2) 170 { 171 return memcmp(k1, k2, sizeof(struct reiserfs_key)); 172 } 173 174 /************************************************************************** 175 * Binary search toolkit function * 176 * Search for an item in the array by the item key * 177 * Returns: 1 if found, 0 if not found; * 178 * *p_n_pos = number of the searched element if found, else the * 179 * number of the first element that is larger than p_v_key. * 180 **************************************************************************/ 181 /* For those not familiar with binary search: n_lbound is the leftmost item that it 182 could be, n_rbound the rightmost item that it could be. We examine the item 183 halfway between n_lbound and n_rbound, and that tells us either that we can increase 184 n_lbound, or decrease n_rbound, or that we have found it, or if n_lbound <= n_rbound that 185 there are no possible items, and we have not found it. With each examination we 186 cut the number of possible items it could be by one more than half rounded down, 187 or we find it. */ 188 static inline int bin_search(const void *p_v_key, /* Key to search for. */ 189 const void *p_v_base, /* First item in the array. */ 190 int p_n_num, /* Number of items in the array. */ 191 int p_n_width, /* Item size in the array. 192 searched. Lest the reader be 193 confused, note that this is crafted 194 as a general function, and when it 195 is applied specifically to the array 196 of item headers in a node, p_n_width 197 is actually the item header size not 198 the item size. */ 199 int *p_n_pos /* Number of the searched for element. */ 200 ) 201 { 202 int n_rbound, n_lbound, n_j; 203 204 for (n_j = ((n_rbound = p_n_num - 1) + (n_lbound = 0)) / 2; 205 n_lbound <= n_rbound; n_j = (n_rbound + n_lbound) / 2) 206 switch (comp_keys 207 ((struct reiserfs_key *)((char *)p_v_base + 208 n_j * p_n_width), 209 (struct cpu_key *)p_v_key)) { 210 case -1: 211 n_lbound = n_j + 1; 212 continue; 213 case 1: 214 n_rbound = n_j - 1; 215 continue; 216 case 0: 217 *p_n_pos = n_j; 218 return ITEM_FOUND; /* Key found in the array. */ 219 } 220 221 /* bin_search did not find given key, it returns position of key, 222 that is minimal and greater than the given one. */ 223 *p_n_pos = n_lbound; 224 return ITEM_NOT_FOUND; 225 } 226 227 #ifdef CONFIG_REISERFS_CHECK 228 extern struct tree_balance *cur_tb; 229 #endif 230 231 /* Minimal possible key. It is never in the tree. */ 232 const struct reiserfs_key MIN_KEY = { 0, 0, {{0, 0},} }; 233 234 /* Maximal possible key. It is never in the tree. */ 235 static const struct reiserfs_key MAX_KEY = { 236 __constant_cpu_to_le32(0xffffffff), 237 __constant_cpu_to_le32(0xffffffff), 238 {{__constant_cpu_to_le32(0xffffffff), 239 __constant_cpu_to_le32(0xffffffff)},} 240 }; 241 242 /* Get delimiting key of the buffer by looking for it in the buffers in the path, starting from the bottom 243 of the path, and going upwards. We must check the path's validity at each step. If the key is not in 244 the path, there is no delimiting key in the tree (buffer is first or last buffer in tree), and in this 245 case we return a special key, either MIN_KEY or MAX_KEY. */ 246 static inline const struct reiserfs_key *get_lkey(const struct treepath 247 *p_s_chk_path, 248 const struct super_block 249 *p_s_sb) 250 { 251 int n_position, n_path_offset = p_s_chk_path->path_length; 252 struct buffer_head *p_s_parent; 253 254 RFALSE(n_path_offset < FIRST_PATH_ELEMENT_OFFSET, 255 "PAP-5010: invalid offset in the path"); 256 257 /* While not higher in path than first element. */ 258 while (n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET) { 259 260 RFALSE(!buffer_uptodate 261 (PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)), 262 "PAP-5020: parent is not uptodate"); 263 264 /* Parent at the path is not in the tree now. */ 265 if (!B_IS_IN_TREE 266 (p_s_parent = 267 PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset))) 268 return &MAX_KEY; 269 /* Check whether position in the parent is correct. */ 270 if ((n_position = 271 PATH_OFFSET_POSITION(p_s_chk_path, 272 n_path_offset)) > 273 B_NR_ITEMS(p_s_parent)) 274 return &MAX_KEY; 275 /* Check whether parent at the path really points to the child. */ 276 if (B_N_CHILD_NUM(p_s_parent, n_position) != 277 PATH_OFFSET_PBUFFER(p_s_chk_path, 278 n_path_offset + 1)->b_blocknr) 279 return &MAX_KEY; 280 /* Return delimiting key if position in the parent is not equal to zero. */ 281 if (n_position) 282 return B_N_PDELIM_KEY(p_s_parent, n_position - 1); 283 } 284 /* Return MIN_KEY if we are in the root of the buffer tree. */ 285 if (PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)-> 286 b_blocknr == SB_ROOT_BLOCK(p_s_sb)) 287 return &MIN_KEY; 288 return &MAX_KEY; 289 } 290 291 /* Get delimiting key of the buffer at the path and its right neighbor. */ 292 inline const struct reiserfs_key *get_rkey(const struct treepath *p_s_chk_path, 293 const struct super_block *p_s_sb) 294 { 295 int n_position, n_path_offset = p_s_chk_path->path_length; 296 struct buffer_head *p_s_parent; 297 298 RFALSE(n_path_offset < FIRST_PATH_ELEMENT_OFFSET, 299 "PAP-5030: invalid offset in the path"); 300 301 while (n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET) { 302 303 RFALSE(!buffer_uptodate 304 (PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)), 305 "PAP-5040: parent is not uptodate"); 306 307 /* Parent at the path is not in the tree now. */ 308 if (!B_IS_IN_TREE 309 (p_s_parent = 310 PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset))) 311 return &MIN_KEY; 312 /* Check whether position in the parent is correct. */ 313 if ((n_position = 314 PATH_OFFSET_POSITION(p_s_chk_path, 315 n_path_offset)) > 316 B_NR_ITEMS(p_s_parent)) 317 return &MIN_KEY; 318 /* Check whether parent at the path really points to the child. */ 319 if (B_N_CHILD_NUM(p_s_parent, n_position) != 320 PATH_OFFSET_PBUFFER(p_s_chk_path, 321 n_path_offset + 1)->b_blocknr) 322 return &MIN_KEY; 323 /* Return delimiting key if position in the parent is not the last one. */ 324 if (n_position != B_NR_ITEMS(p_s_parent)) 325 return B_N_PDELIM_KEY(p_s_parent, n_position); 326 } 327 /* Return MAX_KEY if we are in the root of the buffer tree. */ 328 if (PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)-> 329 b_blocknr == SB_ROOT_BLOCK(p_s_sb)) 330 return &MAX_KEY; 331 return &MIN_KEY; 332 } 333 334 /* Check whether a key is contained in the tree rooted from a buffer at a path. */ 335 /* This works by looking at the left and right delimiting keys for the buffer in the last path_element in 336 the path. These delimiting keys are stored at least one level above that buffer in the tree. If the 337 buffer is the first or last node in the tree order then one of the delimiting keys may be absent, and in 338 this case get_lkey and get_rkey return a special key which is MIN_KEY or MAX_KEY. */ 339 static inline int key_in_buffer(struct treepath *p_s_chk_path, /* Path which should be checked. */ 340 const struct cpu_key *p_s_key, /* Key which should be checked. */ 341 struct super_block *p_s_sb /* Super block pointer. */ 342 ) 343 { 344 345 RFALSE(!p_s_key || p_s_chk_path->path_length < FIRST_PATH_ELEMENT_OFFSET 346 || p_s_chk_path->path_length > MAX_HEIGHT, 347 "PAP-5050: pointer to the key(%p) is NULL or invalid path length(%d)", 348 p_s_key, p_s_chk_path->path_length); 349 RFALSE(!PATH_PLAST_BUFFER(p_s_chk_path)->b_bdev, 350 "PAP-5060: device must not be NODEV"); 351 352 if (comp_keys(get_lkey(p_s_chk_path, p_s_sb), p_s_key) == 1) 353 /* left delimiting key is bigger, that the key we look for */ 354 return 0; 355 // if ( comp_keys(p_s_key, get_rkey(p_s_chk_path, p_s_sb)) != -1 ) 356 if (comp_keys(get_rkey(p_s_chk_path, p_s_sb), p_s_key) != 1) 357 /* p_s_key must be less than right delimitiing key */ 358 return 0; 359 return 1; 360 } 361 362 inline void decrement_bcount(struct buffer_head *p_s_bh) 363 { 364 if (p_s_bh) { 365 if (atomic_read(&(p_s_bh->b_count))) { 366 put_bh(p_s_bh); 367 return; 368 } 369 reiserfs_panic(NULL, 370 "PAP-5070: decrement_bcount: trying to free free buffer %b", 371 p_s_bh); 372 } 373 } 374 375 /* Decrement b_count field of the all buffers in the path. */ 376 void decrement_counters_in_path(struct treepath *p_s_search_path) 377 { 378 int n_path_offset = p_s_search_path->path_length; 379 380 RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET || 381 n_path_offset > EXTENDED_MAX_HEIGHT - 1, 382 "PAP-5080: invalid path offset of %d", n_path_offset); 383 384 while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) { 385 struct buffer_head *bh; 386 387 bh = PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--); 388 decrement_bcount(bh); 389 } 390 p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET; 391 } 392 393 int reiserfs_check_path(struct treepath *p) 394 { 395 RFALSE(p->path_length != ILLEGAL_PATH_ELEMENT_OFFSET, 396 "path not properly relsed"); 397 return 0; 398 } 399 400 /* Release all buffers in the path. Restore dirty bits clean 401 ** when preparing the buffer for the log 402 ** 403 ** only called from fix_nodes() 404 */ 405 void pathrelse_and_restore(struct super_block *s, struct treepath *p_s_search_path) 406 { 407 int n_path_offset = p_s_search_path->path_length; 408 409 RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET, 410 "clm-4000: invalid path offset"); 411 412 while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) { 413 reiserfs_restore_prepared_buffer(s, 414 PATH_OFFSET_PBUFFER 415 (p_s_search_path, 416 n_path_offset)); 417 brelse(PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--)); 418 } 419 p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET; 420 } 421 422 /* Release all buffers in the path. */ 423 void pathrelse(struct treepath *p_s_search_path) 424 { 425 int n_path_offset = p_s_search_path->path_length; 426 427 RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET, 428 "PAP-5090: invalid path offset"); 429 430 while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) 431 brelse(PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--)); 432 433 p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET; 434 } 435 436 static int is_leaf(char *buf, int blocksize, struct buffer_head *bh) 437 { 438 struct block_head *blkh; 439 struct item_head *ih; 440 int used_space; 441 int prev_location; 442 int i; 443 int nr; 444 445 blkh = (struct block_head *)buf; 446 if (blkh_level(blkh) != DISK_LEAF_NODE_LEVEL) { 447 reiserfs_warning(NULL, 448 "is_leaf: this should be caught earlier"); 449 return 0; 450 } 451 452 nr = blkh_nr_item(blkh); 453 if (nr < 1 || nr > ((blocksize - BLKH_SIZE) / (IH_SIZE + MIN_ITEM_LEN))) { 454 /* item number is too big or too small */ 455 reiserfs_warning(NULL, "is_leaf: nr_item seems wrong: %z", bh); 456 return 0; 457 } 458 ih = (struct item_head *)(buf + BLKH_SIZE) + nr - 1; 459 used_space = BLKH_SIZE + IH_SIZE * nr + (blocksize - ih_location(ih)); 460 if (used_space != blocksize - blkh_free_space(blkh)) { 461 /* free space does not match to calculated amount of use space */ 462 reiserfs_warning(NULL, "is_leaf: free space seems wrong: %z", 463 bh); 464 return 0; 465 } 466 // FIXME: it is_leaf will hit performance too much - we may have 467 // return 1 here 468 469 /* check tables of item heads */ 470 ih = (struct item_head *)(buf + BLKH_SIZE); 471 prev_location = blocksize; 472 for (i = 0; i < nr; i++, ih++) { 473 if (le_ih_k_type(ih) == TYPE_ANY) { 474 reiserfs_warning(NULL, 475 "is_leaf: wrong item type for item %h", 476 ih); 477 return 0; 478 } 479 if (ih_location(ih) >= blocksize 480 || ih_location(ih) < IH_SIZE * nr) { 481 reiserfs_warning(NULL, 482 "is_leaf: item location seems wrong: %h", 483 ih); 484 return 0; 485 } 486 if (ih_item_len(ih) < 1 487 || ih_item_len(ih) > MAX_ITEM_LEN(blocksize)) { 488 reiserfs_warning(NULL, 489 "is_leaf: item length seems wrong: %h", 490 ih); 491 return 0; 492 } 493 if (prev_location - ih_location(ih) != ih_item_len(ih)) { 494 reiserfs_warning(NULL, 495 "is_leaf: item location seems wrong (second one): %h", 496 ih); 497 return 0; 498 } 499 prev_location = ih_location(ih); 500 } 501 502 // one may imagine much more checks 503 return 1; 504 } 505 506 /* returns 1 if buf looks like an internal node, 0 otherwise */ 507 static int is_internal(char *buf, int blocksize, struct buffer_head *bh) 508 { 509 struct block_head *blkh; 510 int nr; 511 int used_space; 512 513 blkh = (struct block_head *)buf; 514 nr = blkh_level(blkh); 515 if (nr <= DISK_LEAF_NODE_LEVEL || nr > MAX_HEIGHT) { 516 /* this level is not possible for internal nodes */ 517 reiserfs_warning(NULL, 518 "is_internal: this should be caught earlier"); 519 return 0; 520 } 521 522 nr = blkh_nr_item(blkh); 523 if (nr > (blocksize - BLKH_SIZE - DC_SIZE) / (KEY_SIZE + DC_SIZE)) { 524 /* for internal which is not root we might check min number of keys */ 525 reiserfs_warning(NULL, 526 "is_internal: number of key seems wrong: %z", 527 bh); 528 return 0; 529 } 530 531 used_space = BLKH_SIZE + KEY_SIZE * nr + DC_SIZE * (nr + 1); 532 if (used_space != blocksize - blkh_free_space(blkh)) { 533 reiserfs_warning(NULL, 534 "is_internal: free space seems wrong: %z", bh); 535 return 0; 536 } 537 // one may imagine much more checks 538 return 1; 539 } 540 541 // make sure that bh contains formatted node of reiserfs tree of 542 // 'level'-th level 543 static int is_tree_node(struct buffer_head *bh, int level) 544 { 545 if (B_LEVEL(bh) != level) { 546 reiserfs_warning(NULL, 547 "is_tree_node: node level %d does not match to the expected one %d", 548 B_LEVEL(bh), level); 549 return 0; 550 } 551 if (level == DISK_LEAF_NODE_LEVEL) 552 return is_leaf(bh->b_data, bh->b_size, bh); 553 554 return is_internal(bh->b_data, bh->b_size, bh); 555 } 556 557 #define SEARCH_BY_KEY_READA 16 558 559 /* The function is NOT SCHEDULE-SAFE! */ 560 static void search_by_key_reada(struct super_block *s, 561 struct buffer_head **bh, 562 b_blocknr_t *b, int num) 563 { 564 int i, j; 565 566 for (i = 0; i < num; i++) { 567 bh[i] = sb_getblk(s, b[i]); 568 } 569 for (j = 0; j < i; j++) { 570 /* 571 * note, this needs attention if we are getting rid of the BKL 572 * you have to make sure the prepared bit isn't set on this buffer 573 */ 574 if (!buffer_uptodate(bh[j])) 575 ll_rw_block(READA, 1, bh + j); 576 brelse(bh[j]); 577 } 578 } 579 580 /************************************************************************** 581 * Algorithm SearchByKey * 582 * look for item in the Disk S+Tree by its key * 583 * Input: p_s_sb - super block * 584 * p_s_key - pointer to the key to search * 585 * Output: ITEM_FOUND, ITEM_NOT_FOUND or IO_ERROR * 586 * p_s_search_path - path from the root to the needed leaf * 587 **************************************************************************/ 588 589 /* This function fills up the path from the root to the leaf as it 590 descends the tree looking for the key. It uses reiserfs_bread to 591 try to find buffers in the cache given their block number. If it 592 does not find them in the cache it reads them from disk. For each 593 node search_by_key finds using reiserfs_bread it then uses 594 bin_search to look through that node. bin_search will find the 595 position of the block_number of the next node if it is looking 596 through an internal node. If it is looking through a leaf node 597 bin_search will find the position of the item which has key either 598 equal to given key, or which is the maximal key less than the given 599 key. search_by_key returns a path that must be checked for the 600 correctness of the top of the path but need not be checked for the 601 correctness of the bottom of the path */ 602 /* The function is NOT SCHEDULE-SAFE! */ 603 int search_by_key(struct super_block *p_s_sb, const struct cpu_key *p_s_key, /* Key to search. */ 604 struct treepath *p_s_search_path,/* This structure was 605 allocated and initialized 606 by the calling 607 function. It is filled up 608 by this function. */ 609 int n_stop_level /* How far down the tree to search. To 610 stop at leaf level - set to 611 DISK_LEAF_NODE_LEVEL */ 612 ) 613 { 614 b_blocknr_t n_block_number; 615 int expected_level; 616 struct buffer_head *p_s_bh; 617 struct path_element *p_s_last_element; 618 int n_node_level, n_retval; 619 int right_neighbor_of_leaf_node; 620 int fs_gen; 621 struct buffer_head *reada_bh[SEARCH_BY_KEY_READA]; 622 b_blocknr_t reada_blocks[SEARCH_BY_KEY_READA]; 623 int reada_count = 0; 624 625 #ifdef CONFIG_REISERFS_CHECK 626 int n_repeat_counter = 0; 627 #endif 628 629 PROC_INFO_INC(p_s_sb, search_by_key); 630 631 /* As we add each node to a path we increase its count. This means that 632 we must be careful to release all nodes in a path before we either 633 discard the path struct or re-use the path struct, as we do here. */ 634 635 decrement_counters_in_path(p_s_search_path); 636 637 right_neighbor_of_leaf_node = 0; 638 639 /* With each iteration of this loop we search through the items in the 640 current node, and calculate the next current node(next path element) 641 for the next iteration of this loop.. */ 642 n_block_number = SB_ROOT_BLOCK(p_s_sb); 643 expected_level = -1; 644 while (1) { 645 646 #ifdef CONFIG_REISERFS_CHECK 647 if (!(++n_repeat_counter % 50000)) 648 reiserfs_warning(p_s_sb, "PAP-5100: search_by_key: %s:" 649 "there were %d iterations of while loop " 650 "looking for key %K", 651 current->comm, n_repeat_counter, 652 p_s_key); 653 #endif 654 655 /* prep path to have another element added to it. */ 656 p_s_last_element = 657 PATH_OFFSET_PELEMENT(p_s_search_path, 658 ++p_s_search_path->path_length); 659 fs_gen = get_generation(p_s_sb); 660 661 /* Read the next tree node, and set the last element in the path to 662 have a pointer to it. */ 663 if ((p_s_bh = p_s_last_element->pe_buffer = 664 sb_getblk(p_s_sb, n_block_number))) { 665 if (!buffer_uptodate(p_s_bh) && reada_count > 1) { 666 search_by_key_reada(p_s_sb, reada_bh, 667 reada_blocks, reada_count); 668 } 669 ll_rw_block(READ, 1, &p_s_bh); 670 wait_on_buffer(p_s_bh); 671 if (!buffer_uptodate(p_s_bh)) 672 goto io_error; 673 } else { 674 io_error: 675 p_s_search_path->path_length--; 676 pathrelse(p_s_search_path); 677 return IO_ERROR; 678 } 679 reada_count = 0; 680 if (expected_level == -1) 681 expected_level = SB_TREE_HEIGHT(p_s_sb); 682 expected_level--; 683 684 /* It is possible that schedule occurred. We must check whether the key 685 to search is still in the tree rooted from the current buffer. If 686 not then repeat search from the root. */ 687 if (fs_changed(fs_gen, p_s_sb) && 688 (!B_IS_IN_TREE(p_s_bh) || 689 B_LEVEL(p_s_bh) != expected_level || 690 !key_in_buffer(p_s_search_path, p_s_key, p_s_sb))) { 691 PROC_INFO_INC(p_s_sb, search_by_key_fs_changed); 692 PROC_INFO_INC(p_s_sb, search_by_key_restarted); 693 PROC_INFO_INC(p_s_sb, 694 sbk_restarted[expected_level - 1]); 695 decrement_counters_in_path(p_s_search_path); 696 697 /* Get the root block number so that we can repeat the search 698 starting from the root. */ 699 n_block_number = SB_ROOT_BLOCK(p_s_sb); 700 expected_level = -1; 701 right_neighbor_of_leaf_node = 0; 702 703 /* repeat search from the root */ 704 continue; 705 } 706 707 /* only check that the key is in the buffer if p_s_key is not 708 equal to the MAX_KEY. Latter case is only possible in 709 "finish_unfinished()" processing during mount. */ 710 RFALSE(comp_keys(&MAX_KEY, p_s_key) && 711 !key_in_buffer(p_s_search_path, p_s_key, p_s_sb), 712 "PAP-5130: key is not in the buffer"); 713 #ifdef CONFIG_REISERFS_CHECK 714 if (cur_tb) { 715 print_cur_tb("5140"); 716 reiserfs_panic(p_s_sb, 717 "PAP-5140: search_by_key: schedule occurred in do_balance!"); 718 } 719 #endif 720 721 // make sure, that the node contents look like a node of 722 // certain level 723 if (!is_tree_node(p_s_bh, expected_level)) { 724 reiserfs_warning(p_s_sb, "vs-5150: search_by_key: " 725 "invalid format found in block %ld. Fsck?", 726 p_s_bh->b_blocknr); 727 pathrelse(p_s_search_path); 728 return IO_ERROR; 729 } 730 731 /* ok, we have acquired next formatted node in the tree */ 732 n_node_level = B_LEVEL(p_s_bh); 733 734 PROC_INFO_BH_STAT(p_s_sb, p_s_bh, n_node_level - 1); 735 736 RFALSE(n_node_level < n_stop_level, 737 "vs-5152: tree level (%d) is less than stop level (%d)", 738 n_node_level, n_stop_level); 739 740 n_retval = bin_search(p_s_key, B_N_PITEM_HEAD(p_s_bh, 0), 741 B_NR_ITEMS(p_s_bh), 742 (n_node_level == 743 DISK_LEAF_NODE_LEVEL) ? IH_SIZE : 744 KEY_SIZE, 745 &(p_s_last_element->pe_position)); 746 if (n_node_level == n_stop_level) { 747 return n_retval; 748 } 749 750 /* we are not in the stop level */ 751 if (n_retval == ITEM_FOUND) 752 /* item has been found, so we choose the pointer which is to the right of the found one */ 753 p_s_last_element->pe_position++; 754 755 /* if item was not found we choose the position which is to 756 the left of the found item. This requires no code, 757 bin_search did it already. */ 758 759 /* So we have chosen a position in the current node which is 760 an internal node. Now we calculate child block number by 761 position in the node. */ 762 n_block_number = 763 B_N_CHILD_NUM(p_s_bh, p_s_last_element->pe_position); 764 765 /* if we are going to read leaf nodes, try for read ahead as well */ 766 if ((p_s_search_path->reada & PATH_READA) && 767 n_node_level == DISK_LEAF_NODE_LEVEL + 1) { 768 int pos = p_s_last_element->pe_position; 769 int limit = B_NR_ITEMS(p_s_bh); 770 struct reiserfs_key *le_key; 771 772 if (p_s_search_path->reada & PATH_READA_BACK) 773 limit = 0; 774 while (reada_count < SEARCH_BY_KEY_READA) { 775 if (pos == limit) 776 break; 777 reada_blocks[reada_count++] = 778 B_N_CHILD_NUM(p_s_bh, pos); 779 if (p_s_search_path->reada & PATH_READA_BACK) 780 pos--; 781 else 782 pos++; 783 784 /* 785 * check to make sure we're in the same object 786 */ 787 le_key = B_N_PDELIM_KEY(p_s_bh, pos); 788 if (le32_to_cpu(le_key->k_objectid) != 789 p_s_key->on_disk_key.k_objectid) { 790 break; 791 } 792 } 793 } 794 } 795 } 796 797 /* Form the path to an item and position in this item which contains 798 file byte defined by p_s_key. If there is no such item 799 corresponding to the key, we point the path to the item with 800 maximal key less than p_s_key, and *p_n_pos_in_item is set to one 801 past the last entry/byte in the item. If searching for entry in a 802 directory item, and it is not found, *p_n_pos_in_item is set to one 803 entry more than the entry with maximal key which is less than the 804 sought key. 805 806 Note that if there is no entry in this same node which is one more, 807 then we point to an imaginary entry. for direct items, the 808 position is in units of bytes, for indirect items the position is 809 in units of blocknr entries, for directory items the position is in 810 units of directory entries. */ 811 812 /* The function is NOT SCHEDULE-SAFE! */ 813 int search_for_position_by_key(struct super_block *p_s_sb, /* Pointer to the super block. */ 814 const struct cpu_key *p_cpu_key, /* Key to search (cpu variable) */ 815 struct treepath *p_s_search_path /* Filled up by this function. */ 816 ) 817 { 818 struct item_head *p_le_ih; /* pointer to on-disk structure */ 819 int n_blk_size; 820 loff_t item_offset, offset; 821 struct reiserfs_dir_entry de; 822 int retval; 823 824 /* If searching for directory entry. */ 825 if (is_direntry_cpu_key(p_cpu_key)) 826 return search_by_entry_key(p_s_sb, p_cpu_key, p_s_search_path, 827 &de); 828 829 /* If not searching for directory entry. */ 830 831 /* If item is found. */ 832 retval = search_item(p_s_sb, p_cpu_key, p_s_search_path); 833 if (retval == IO_ERROR) 834 return retval; 835 if (retval == ITEM_FOUND) { 836 837 RFALSE(!ih_item_len 838 (B_N_PITEM_HEAD 839 (PATH_PLAST_BUFFER(p_s_search_path), 840 PATH_LAST_POSITION(p_s_search_path))), 841 "PAP-5165: item length equals zero"); 842 843 pos_in_item(p_s_search_path) = 0; 844 return POSITION_FOUND; 845 } 846 847 RFALSE(!PATH_LAST_POSITION(p_s_search_path), 848 "PAP-5170: position equals zero"); 849 850 /* Item is not found. Set path to the previous item. */ 851 p_le_ih = 852 B_N_PITEM_HEAD(PATH_PLAST_BUFFER(p_s_search_path), 853 --PATH_LAST_POSITION(p_s_search_path)); 854 n_blk_size = p_s_sb->s_blocksize; 855 856 if (comp_short_keys(&(p_le_ih->ih_key), p_cpu_key)) { 857 return FILE_NOT_FOUND; 858 } 859 // FIXME: quite ugly this far 860 861 item_offset = le_ih_k_offset(p_le_ih); 862 offset = cpu_key_k_offset(p_cpu_key); 863 864 /* Needed byte is contained in the item pointed to by the path. */ 865 if (item_offset <= offset && 866 item_offset + op_bytes_number(p_le_ih, n_blk_size) > offset) { 867 pos_in_item(p_s_search_path) = offset - item_offset; 868 if (is_indirect_le_ih(p_le_ih)) { 869 pos_in_item(p_s_search_path) /= n_blk_size; 870 } 871 return POSITION_FOUND; 872 } 873 874 /* Needed byte is not contained in the item pointed to by the 875 path. Set pos_in_item out of the item. */ 876 if (is_indirect_le_ih(p_le_ih)) 877 pos_in_item(p_s_search_path) = 878 ih_item_len(p_le_ih) / UNFM_P_SIZE; 879 else 880 pos_in_item(p_s_search_path) = ih_item_len(p_le_ih); 881 882 return POSITION_NOT_FOUND; 883 } 884 885 /* Compare given item and item pointed to by the path. */ 886 int comp_items(const struct item_head *stored_ih, const struct treepath *p_s_path) 887 { 888 struct buffer_head *p_s_bh; 889 struct item_head *ih; 890 891 /* Last buffer at the path is not in the tree. */ 892 if (!B_IS_IN_TREE(p_s_bh = PATH_PLAST_BUFFER(p_s_path))) 893 return 1; 894 895 /* Last path position is invalid. */ 896 if (PATH_LAST_POSITION(p_s_path) >= B_NR_ITEMS(p_s_bh)) 897 return 1; 898 899 /* we need only to know, whether it is the same item */ 900 ih = get_ih(p_s_path); 901 return memcmp(stored_ih, ih, IH_SIZE); 902 } 903 904 /* unformatted nodes are not logged anymore, ever. This is safe 905 ** now 906 */ 907 #define held_by_others(bh) (atomic_read(&(bh)->b_count) > 1) 908 909 // block can not be forgotten as it is in I/O or held by someone 910 #define block_in_use(bh) (buffer_locked(bh) || (held_by_others(bh))) 911 912 // prepare for delete or cut of direct item 913 static inline int prepare_for_direct_item(struct treepath *path, 914 struct item_head *le_ih, 915 struct inode *inode, 916 loff_t new_file_length, int *cut_size) 917 { 918 loff_t round_len; 919 920 if (new_file_length == max_reiserfs_offset(inode)) { 921 /* item has to be deleted */ 922 *cut_size = -(IH_SIZE + ih_item_len(le_ih)); 923 return M_DELETE; 924 } 925 // new file gets truncated 926 if (get_inode_item_key_version(inode) == KEY_FORMAT_3_6) { 927 // 928 round_len = ROUND_UP(new_file_length); 929 /* this was n_new_file_length < le_ih ... */ 930 if (round_len < le_ih_k_offset(le_ih)) { 931 *cut_size = -(IH_SIZE + ih_item_len(le_ih)); 932 return M_DELETE; /* Delete this item. */ 933 } 934 /* Calculate first position and size for cutting from item. */ 935 pos_in_item(path) = round_len - (le_ih_k_offset(le_ih) - 1); 936 *cut_size = -(ih_item_len(le_ih) - pos_in_item(path)); 937 938 return M_CUT; /* Cut from this item. */ 939 } 940 941 // old file: items may have any length 942 943 if (new_file_length < le_ih_k_offset(le_ih)) { 944 *cut_size = -(IH_SIZE + ih_item_len(le_ih)); 945 return M_DELETE; /* Delete this item. */ 946 } 947 /* Calculate first position and size for cutting from item. */ 948 *cut_size = -(ih_item_len(le_ih) - 949 (pos_in_item(path) = 950 new_file_length + 1 - le_ih_k_offset(le_ih))); 951 return M_CUT; /* Cut from this item. */ 952 } 953 954 static inline int prepare_for_direntry_item(struct treepath *path, 955 struct item_head *le_ih, 956 struct inode *inode, 957 loff_t new_file_length, 958 int *cut_size) 959 { 960 if (le_ih_k_offset(le_ih) == DOT_OFFSET && 961 new_file_length == max_reiserfs_offset(inode)) { 962 RFALSE(ih_entry_count(le_ih) != 2, 963 "PAP-5220: incorrect empty directory item (%h)", le_ih); 964 *cut_size = -(IH_SIZE + ih_item_len(le_ih)); 965 return M_DELETE; /* Delete the directory item containing "." and ".." entry. */ 966 } 967 968 if (ih_entry_count(le_ih) == 1) { 969 /* Delete the directory item such as there is one record only 970 in this item */ 971 *cut_size = -(IH_SIZE + ih_item_len(le_ih)); 972 return M_DELETE; 973 } 974 975 /* Cut one record from the directory item. */ 976 *cut_size = 977 -(DEH_SIZE + 978 entry_length(get_last_bh(path), le_ih, pos_in_item(path))); 979 return M_CUT; 980 } 981 982 #define JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD (2 * JOURNAL_PER_BALANCE_CNT + 1) 983 984 /* If the path points to a directory or direct item, calculate mode and the size cut, for balance. 985 If the path points to an indirect item, remove some number of its unformatted nodes. 986 In case of file truncate calculate whether this item must be deleted/truncated or last 987 unformatted node of this item will be converted to a direct item. 988 This function returns a determination of what balance mode the calling function should employ. */ 989 static char prepare_for_delete_or_cut(struct reiserfs_transaction_handle *th, struct inode *inode, struct treepath *p_s_path, const struct cpu_key *p_s_item_key, int *p_n_removed, /* Number of unformatted nodes which were removed 990 from end of the file. */ 991 int *p_n_cut_size, unsigned long long n_new_file_length /* MAX_KEY_OFFSET in case of delete. */ 992 ) 993 { 994 struct super_block *p_s_sb = inode->i_sb; 995 struct item_head *p_le_ih = PATH_PITEM_HEAD(p_s_path); 996 struct buffer_head *p_s_bh = PATH_PLAST_BUFFER(p_s_path); 997 998 BUG_ON(!th->t_trans_id); 999 1000 /* Stat_data item. */ 1001 if (is_statdata_le_ih(p_le_ih)) { 1002 1003 RFALSE(n_new_file_length != max_reiserfs_offset(inode), 1004 "PAP-5210: mode must be M_DELETE"); 1005 1006 *p_n_cut_size = -(IH_SIZE + ih_item_len(p_le_ih)); 1007 return M_DELETE; 1008 } 1009 1010 /* Directory item. */ 1011 if (is_direntry_le_ih(p_le_ih)) 1012 return prepare_for_direntry_item(p_s_path, p_le_ih, inode, 1013 n_new_file_length, 1014 p_n_cut_size); 1015 1016 /* Direct item. */ 1017 if (is_direct_le_ih(p_le_ih)) 1018 return prepare_for_direct_item(p_s_path, p_le_ih, inode, 1019 n_new_file_length, p_n_cut_size); 1020 1021 /* Case of an indirect item. */ 1022 { 1023 int blk_size = p_s_sb->s_blocksize; 1024 struct item_head s_ih; 1025 int need_re_search; 1026 int delete = 0; 1027 int result = M_CUT; 1028 int pos = 0; 1029 1030 if ( n_new_file_length == max_reiserfs_offset (inode) ) { 1031 /* prepare_for_delete_or_cut() is called by 1032 * reiserfs_delete_item() */ 1033 n_new_file_length = 0; 1034 delete = 1; 1035 } 1036 1037 do { 1038 need_re_search = 0; 1039 *p_n_cut_size = 0; 1040 p_s_bh = PATH_PLAST_BUFFER(p_s_path); 1041 copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path)); 1042 pos = I_UNFM_NUM(&s_ih); 1043 1044 while (le_ih_k_offset (&s_ih) + (pos - 1) * blk_size > n_new_file_length) { 1045 __le32 *unfm; 1046 __u32 block; 1047 1048 /* Each unformatted block deletion may involve one additional 1049 * bitmap block into the transaction, thereby the initial 1050 * journal space reservation might not be enough. */ 1051 if (!delete && (*p_n_cut_size) != 0 && 1052 reiserfs_transaction_free_space(th) < JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD) { 1053 break; 1054 } 1055 1056 unfm = (__le32 *)B_I_PITEM(p_s_bh, &s_ih) + pos - 1; 1057 block = get_block_num(unfm, 0); 1058 1059 if (block != 0) { 1060 reiserfs_prepare_for_journal(p_s_sb, p_s_bh, 1); 1061 put_block_num(unfm, 0, 0); 1062 journal_mark_dirty (th, p_s_sb, p_s_bh); 1063 reiserfs_free_block(th, inode, block, 1); 1064 } 1065 1066 cond_resched(); 1067 1068 if (item_moved (&s_ih, p_s_path)) { 1069 need_re_search = 1; 1070 break; 1071 } 1072 1073 pos --; 1074 (*p_n_removed) ++; 1075 (*p_n_cut_size) -= UNFM_P_SIZE; 1076 1077 if (pos == 0) { 1078 (*p_n_cut_size) -= IH_SIZE; 1079 result = M_DELETE; 1080 break; 1081 } 1082 } 1083 /* a trick. If the buffer has been logged, this will do nothing. If 1084 ** we've broken the loop without logging it, it will restore the 1085 ** buffer */ 1086 reiserfs_restore_prepared_buffer(p_s_sb, p_s_bh); 1087 } while (need_re_search && 1088 search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path) == POSITION_FOUND); 1089 pos_in_item(p_s_path) = pos * UNFM_P_SIZE; 1090 1091 if (*p_n_cut_size == 0) { 1092 /* Nothing were cut. maybe convert last unformatted node to the 1093 * direct item? */ 1094 result = M_CONVERT; 1095 } 1096 return result; 1097 } 1098 } 1099 1100 /* Calculate number of bytes which will be deleted or cut during balance */ 1101 static int calc_deleted_bytes_number(struct tree_balance *p_s_tb, char c_mode) 1102 { 1103 int n_del_size; 1104 struct item_head *p_le_ih = PATH_PITEM_HEAD(p_s_tb->tb_path); 1105 1106 if (is_statdata_le_ih(p_le_ih)) 1107 return 0; 1108 1109 n_del_size = 1110 (c_mode == 1111 M_DELETE) ? ih_item_len(p_le_ih) : -p_s_tb->insert_size[0]; 1112 if (is_direntry_le_ih(p_le_ih)) { 1113 // return EMPTY_DIR_SIZE; /* We delete emty directoris only. */ 1114 // we can't use EMPTY_DIR_SIZE, as old format dirs have a different 1115 // empty size. ick. FIXME, is this right? 1116 // 1117 return n_del_size; 1118 } 1119 1120 if (is_indirect_le_ih(p_le_ih)) 1121 n_del_size = (n_del_size / UNFM_P_SIZE) * (PATH_PLAST_BUFFER(p_s_tb->tb_path)->b_size); // - get_ih_free_space (p_le_ih); 1122 return n_del_size; 1123 } 1124 1125 static void init_tb_struct(struct reiserfs_transaction_handle *th, 1126 struct tree_balance *p_s_tb, 1127 struct super_block *p_s_sb, 1128 struct treepath *p_s_path, int n_size) 1129 { 1130 1131 BUG_ON(!th->t_trans_id); 1132 1133 memset(p_s_tb, '\0', sizeof(struct tree_balance)); 1134 p_s_tb->transaction_handle = th; 1135 p_s_tb->tb_sb = p_s_sb; 1136 p_s_tb->tb_path = p_s_path; 1137 PATH_OFFSET_PBUFFER(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = NULL; 1138 PATH_OFFSET_POSITION(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = 0; 1139 p_s_tb->insert_size[0] = n_size; 1140 } 1141 1142 void padd_item(char *item, int total_length, int length) 1143 { 1144 int i; 1145 1146 for (i = total_length; i > length;) 1147 item[--i] = 0; 1148 } 1149 1150 #ifdef REISERQUOTA_DEBUG 1151 char key2type(struct reiserfs_key *ih) 1152 { 1153 if (is_direntry_le_key(2, ih)) 1154 return 'd'; 1155 if (is_direct_le_key(2, ih)) 1156 return 'D'; 1157 if (is_indirect_le_key(2, ih)) 1158 return 'i'; 1159 if (is_statdata_le_key(2, ih)) 1160 return 's'; 1161 return 'u'; 1162 } 1163 1164 char head2type(struct item_head *ih) 1165 { 1166 if (is_direntry_le_ih(ih)) 1167 return 'd'; 1168 if (is_direct_le_ih(ih)) 1169 return 'D'; 1170 if (is_indirect_le_ih(ih)) 1171 return 'i'; 1172 if (is_statdata_le_ih(ih)) 1173 return 's'; 1174 return 'u'; 1175 } 1176 #endif 1177 1178 /* Delete object item. */ 1179 int reiserfs_delete_item(struct reiserfs_transaction_handle *th, struct treepath *p_s_path, /* Path to the deleted item. */ 1180 const struct cpu_key *p_s_item_key, /* Key to search for the deleted item. */ 1181 struct inode *p_s_inode, /* inode is here just to update i_blocks and quotas */ 1182 struct buffer_head *p_s_un_bh) 1183 { /* NULL or unformatted node pointer. */ 1184 struct super_block *p_s_sb = p_s_inode->i_sb; 1185 struct tree_balance s_del_balance; 1186 struct item_head s_ih; 1187 struct item_head *q_ih; 1188 int quota_cut_bytes; 1189 int n_ret_value, n_del_size, n_removed; 1190 1191 #ifdef CONFIG_REISERFS_CHECK 1192 char c_mode; 1193 int n_iter = 0; 1194 #endif 1195 1196 BUG_ON(!th->t_trans_id); 1197 1198 init_tb_struct(th, &s_del_balance, p_s_sb, p_s_path, 1199 0 /*size is unknown */ ); 1200 1201 while (1) { 1202 n_removed = 0; 1203 1204 #ifdef CONFIG_REISERFS_CHECK 1205 n_iter++; 1206 c_mode = 1207 #endif 1208 prepare_for_delete_or_cut(th, p_s_inode, p_s_path, 1209 p_s_item_key, &n_removed, 1210 &n_del_size, 1211 max_reiserfs_offset(p_s_inode)); 1212 1213 RFALSE(c_mode != M_DELETE, "PAP-5320: mode must be M_DELETE"); 1214 1215 copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path)); 1216 s_del_balance.insert_size[0] = n_del_size; 1217 1218 n_ret_value = fix_nodes(M_DELETE, &s_del_balance, NULL, NULL); 1219 if (n_ret_value != REPEAT_SEARCH) 1220 break; 1221 1222 PROC_INFO_INC(p_s_sb, delete_item_restarted); 1223 1224 // file system changed, repeat search 1225 n_ret_value = 1226 search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path); 1227 if (n_ret_value == IO_ERROR) 1228 break; 1229 if (n_ret_value == FILE_NOT_FOUND) { 1230 reiserfs_warning(p_s_sb, 1231 "vs-5340: reiserfs_delete_item: " 1232 "no items of the file %K found", 1233 p_s_item_key); 1234 break; 1235 } 1236 } /* while (1) */ 1237 1238 if (n_ret_value != CARRY_ON) { 1239 unfix_nodes(&s_del_balance); 1240 return 0; 1241 } 1242 // reiserfs_delete_item returns item length when success 1243 n_ret_value = calc_deleted_bytes_number(&s_del_balance, M_DELETE); 1244 q_ih = get_ih(p_s_path); 1245 quota_cut_bytes = ih_item_len(q_ih); 1246 1247 /* hack so the quota code doesn't have to guess if the file 1248 ** has a tail. On tail insert, we allocate quota for 1 unformatted node. 1249 ** We test the offset because the tail might have been 1250 ** split into multiple items, and we only want to decrement for 1251 ** the unfm node once 1252 */ 1253 if (!S_ISLNK(p_s_inode->i_mode) && is_direct_le_ih(q_ih)) { 1254 if ((le_ih_k_offset(q_ih) & (p_s_sb->s_blocksize - 1)) == 1) { 1255 quota_cut_bytes = p_s_sb->s_blocksize + UNFM_P_SIZE; 1256 } else { 1257 quota_cut_bytes = 0; 1258 } 1259 } 1260 1261 if (p_s_un_bh) { 1262 int off; 1263 char *data; 1264 1265 /* We are in direct2indirect conversion, so move tail contents 1266 to the unformatted node */ 1267 /* note, we do the copy before preparing the buffer because we 1268 ** don't care about the contents of the unformatted node yet. 1269 ** the only thing we really care about is the direct item's data 1270 ** is in the unformatted node. 1271 ** 1272 ** Otherwise, we would have to call reiserfs_prepare_for_journal on 1273 ** the unformatted node, which might schedule, meaning we'd have to 1274 ** loop all the way back up to the start of the while loop. 1275 ** 1276 ** The unformatted node must be dirtied later on. We can't be 1277 ** sure here if the entire tail has been deleted yet. 1278 ** 1279 ** p_s_un_bh is from the page cache (all unformatted nodes are 1280 ** from the page cache) and might be a highmem page. So, we 1281 ** can't use p_s_un_bh->b_data. 1282 ** -clm 1283 */ 1284 1285 data = kmap_atomic(p_s_un_bh->b_page, KM_USER0); 1286 off = ((le_ih_k_offset(&s_ih) - 1) & (PAGE_CACHE_SIZE - 1)); 1287 memcpy(data + off, 1288 B_I_PITEM(PATH_PLAST_BUFFER(p_s_path), &s_ih), 1289 n_ret_value); 1290 kunmap_atomic(data, KM_USER0); 1291 } 1292 /* Perform balancing after all resources have been collected at once. */ 1293 do_balance(&s_del_balance, NULL, NULL, M_DELETE); 1294 1295 #ifdef REISERQUOTA_DEBUG 1296 reiserfs_debug(p_s_sb, REISERFS_DEBUG_CODE, 1297 "reiserquota delete_item(): freeing %u, id=%u type=%c", 1298 quota_cut_bytes, p_s_inode->i_uid, head2type(&s_ih)); 1299 #endif 1300 DQUOT_FREE_SPACE_NODIRTY(p_s_inode, quota_cut_bytes); 1301 1302 /* Return deleted body length */ 1303 return n_ret_value; 1304 } 1305 1306 /* Summary Of Mechanisms For Handling Collisions Between Processes: 1307 1308 deletion of the body of the object is performed by iput(), with the 1309 result that if multiple processes are operating on a file, the 1310 deletion of the body of the file is deferred until the last process 1311 that has an open inode performs its iput(). 1312 1313 writes and truncates are protected from collisions by use of 1314 semaphores. 1315 1316 creates, linking, and mknod are protected from collisions with other 1317 processes by making the reiserfs_add_entry() the last step in the 1318 creation, and then rolling back all changes if there was a collision. 1319 - Hans 1320 */ 1321 1322 /* this deletes item which never gets split */ 1323 void reiserfs_delete_solid_item(struct reiserfs_transaction_handle *th, 1324 struct inode *inode, struct reiserfs_key *key) 1325 { 1326 struct tree_balance tb; 1327 INITIALIZE_PATH(path); 1328 int item_len = 0; 1329 int tb_init = 0; 1330 struct cpu_key cpu_key; 1331 int retval; 1332 int quota_cut_bytes = 0; 1333 1334 BUG_ON(!th->t_trans_id); 1335 1336 le_key2cpu_key(&cpu_key, key); 1337 1338 while (1) { 1339 retval = search_item(th->t_super, &cpu_key, &path); 1340 if (retval == IO_ERROR) { 1341 reiserfs_warning(th->t_super, 1342 "vs-5350: reiserfs_delete_solid_item: " 1343 "i/o failure occurred trying to delete %K", 1344 &cpu_key); 1345 break; 1346 } 1347 if (retval != ITEM_FOUND) { 1348 pathrelse(&path); 1349 // No need for a warning, if there is just no free space to insert '..' item into the newly-created subdir 1350 if (! 1351 ((unsigned long long) 1352 GET_HASH_VALUE(le_key_k_offset 1353 (le_key_version(key), key)) == 0 1354 && (unsigned long long) 1355 GET_GENERATION_NUMBER(le_key_k_offset 1356 (le_key_version(key), 1357 key)) == 1)) 1358 reiserfs_warning(th->t_super, 1359 "vs-5355: reiserfs_delete_solid_item: %k not found", 1360 key); 1361 break; 1362 } 1363 if (!tb_init) { 1364 tb_init = 1; 1365 item_len = ih_item_len(PATH_PITEM_HEAD(&path)); 1366 init_tb_struct(th, &tb, th->t_super, &path, 1367 -(IH_SIZE + item_len)); 1368 } 1369 quota_cut_bytes = ih_item_len(PATH_PITEM_HEAD(&path)); 1370 1371 retval = fix_nodes(M_DELETE, &tb, NULL, NULL); 1372 if (retval == REPEAT_SEARCH) { 1373 PROC_INFO_INC(th->t_super, delete_solid_item_restarted); 1374 continue; 1375 } 1376 1377 if (retval == CARRY_ON) { 1378 do_balance(&tb, NULL, NULL, M_DELETE); 1379 if (inode) { /* Should we count quota for item? (we don't count quotas for save-links) */ 1380 #ifdef REISERQUOTA_DEBUG 1381 reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE, 1382 "reiserquota delete_solid_item(): freeing %u id=%u type=%c", 1383 quota_cut_bytes, inode->i_uid, 1384 key2type(key)); 1385 #endif 1386 DQUOT_FREE_SPACE_NODIRTY(inode, 1387 quota_cut_bytes); 1388 } 1389 break; 1390 } 1391 // IO_ERROR, NO_DISK_SPACE, etc 1392 reiserfs_warning(th->t_super, 1393 "vs-5360: reiserfs_delete_solid_item: " 1394 "could not delete %K due to fix_nodes failure", 1395 &cpu_key); 1396 unfix_nodes(&tb); 1397 break; 1398 } 1399 1400 reiserfs_check_path(&path); 1401 } 1402 1403 int reiserfs_delete_object(struct reiserfs_transaction_handle *th, 1404 struct inode *inode) 1405 { 1406 int err; 1407 inode->i_size = 0; 1408 BUG_ON(!th->t_trans_id); 1409 1410 /* for directory this deletes item containing "." and ".." */ 1411 err = 1412 reiserfs_do_truncate(th, inode, NULL, 0 /*no timestamp updates */ ); 1413 if (err) 1414 return err; 1415 1416 #if defined( USE_INODE_GENERATION_COUNTER ) 1417 if (!old_format_only(th->t_super)) { 1418 __le32 *inode_generation; 1419 1420 inode_generation = 1421 &REISERFS_SB(th->t_super)->s_rs->s_inode_generation; 1422 le32_add_cpu(inode_generation, 1); 1423 } 1424 /* USE_INODE_GENERATION_COUNTER */ 1425 #endif 1426 reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode)); 1427 1428 return err; 1429 } 1430 1431 static void unmap_buffers(struct page *page, loff_t pos) 1432 { 1433 struct buffer_head *bh; 1434 struct buffer_head *head; 1435 struct buffer_head *next; 1436 unsigned long tail_index; 1437 unsigned long cur_index; 1438 1439 if (page) { 1440 if (page_has_buffers(page)) { 1441 tail_index = pos & (PAGE_CACHE_SIZE - 1); 1442 cur_index = 0; 1443 head = page_buffers(page); 1444 bh = head; 1445 do { 1446 next = bh->b_this_page; 1447 1448 /* we want to unmap the buffers that contain the tail, and 1449 ** all the buffers after it (since the tail must be at the 1450 ** end of the file). We don't want to unmap file data 1451 ** before the tail, since it might be dirty and waiting to 1452 ** reach disk 1453 */ 1454 cur_index += bh->b_size; 1455 if (cur_index > tail_index) { 1456 reiserfs_unmap_buffer(bh); 1457 } 1458 bh = next; 1459 } while (bh != head); 1460 } 1461 } 1462 } 1463 1464 static int maybe_indirect_to_direct(struct reiserfs_transaction_handle *th, 1465 struct inode *p_s_inode, 1466 struct page *page, 1467 struct treepath *p_s_path, 1468 const struct cpu_key *p_s_item_key, 1469 loff_t n_new_file_size, char *p_c_mode) 1470 { 1471 struct super_block *p_s_sb = p_s_inode->i_sb; 1472 int n_block_size = p_s_sb->s_blocksize; 1473 int cut_bytes; 1474 BUG_ON(!th->t_trans_id); 1475 BUG_ON(n_new_file_size != p_s_inode->i_size); 1476 1477 /* the page being sent in could be NULL if there was an i/o error 1478 ** reading in the last block. The user will hit problems trying to 1479 ** read the file, but for now we just skip the indirect2direct 1480 */ 1481 if (atomic_read(&p_s_inode->i_count) > 1 || 1482 !tail_has_to_be_packed(p_s_inode) || 1483 !page || (REISERFS_I(p_s_inode)->i_flags & i_nopack_mask)) { 1484 // leave tail in an unformatted node 1485 *p_c_mode = M_SKIP_BALANCING; 1486 cut_bytes = 1487 n_block_size - (n_new_file_size & (n_block_size - 1)); 1488 pathrelse(p_s_path); 1489 return cut_bytes; 1490 } 1491 /* Permorm the conversion to a direct_item. */ 1492 /*return indirect_to_direct (p_s_inode, p_s_path, p_s_item_key, n_new_file_size, p_c_mode); */ 1493 return indirect2direct(th, p_s_inode, page, p_s_path, p_s_item_key, 1494 n_new_file_size, p_c_mode); 1495 } 1496 1497 /* we did indirect_to_direct conversion. And we have inserted direct 1498 item successesfully, but there were no disk space to cut unfm 1499 pointer being converted. Therefore we have to delete inserted 1500 direct item(s) */ 1501 static void indirect_to_direct_roll_back(struct reiserfs_transaction_handle *th, 1502 struct inode *inode, struct treepath *path) 1503 { 1504 struct cpu_key tail_key; 1505 int tail_len; 1506 int removed; 1507 BUG_ON(!th->t_trans_id); 1508 1509 make_cpu_key(&tail_key, inode, inode->i_size + 1, TYPE_DIRECT, 4); // !!!! 1510 tail_key.key_length = 4; 1511 1512 tail_len = 1513 (cpu_key_k_offset(&tail_key) & (inode->i_sb->s_blocksize - 1)) - 1; 1514 while (tail_len) { 1515 /* look for the last byte of the tail */ 1516 if (search_for_position_by_key(inode->i_sb, &tail_key, path) == 1517 POSITION_NOT_FOUND) 1518 reiserfs_panic(inode->i_sb, 1519 "vs-5615: indirect_to_direct_roll_back: found invalid item"); 1520 RFALSE(path->pos_in_item != 1521 ih_item_len(PATH_PITEM_HEAD(path)) - 1, 1522 "vs-5616: appended bytes found"); 1523 PATH_LAST_POSITION(path)--; 1524 1525 removed = 1526 reiserfs_delete_item(th, path, &tail_key, inode, 1527 NULL /*unbh not needed */ ); 1528 RFALSE(removed <= 0 1529 || removed > tail_len, 1530 "vs-5617: there was tail %d bytes, removed item length %d bytes", 1531 tail_len, removed); 1532 tail_len -= removed; 1533 set_cpu_key_k_offset(&tail_key, 1534 cpu_key_k_offset(&tail_key) - removed); 1535 } 1536 reiserfs_warning(inode->i_sb, 1537 "indirect_to_direct_roll_back: indirect_to_direct conversion has been rolled back due to lack of disk space"); 1538 //mark_file_without_tail (inode); 1539 mark_inode_dirty(inode); 1540 } 1541 1542 /* (Truncate or cut entry) or delete object item. Returns < 0 on failure */ 1543 int reiserfs_cut_from_item(struct reiserfs_transaction_handle *th, 1544 struct treepath *p_s_path, 1545 struct cpu_key *p_s_item_key, 1546 struct inode *p_s_inode, 1547 struct page *page, loff_t n_new_file_size) 1548 { 1549 struct super_block *p_s_sb = p_s_inode->i_sb; 1550 /* Every function which is going to call do_balance must first 1551 create a tree_balance structure. Then it must fill up this 1552 structure by using the init_tb_struct and fix_nodes functions. 1553 After that we can make tree balancing. */ 1554 struct tree_balance s_cut_balance; 1555 struct item_head *p_le_ih; 1556 int n_cut_size = 0, /* Amount to be cut. */ 1557 n_ret_value = CARRY_ON, n_removed = 0, /* Number of the removed unformatted nodes. */ 1558 n_is_inode_locked = 0; 1559 char c_mode; /* Mode of the balance. */ 1560 int retval2 = -1; 1561 int quota_cut_bytes; 1562 loff_t tail_pos = 0; 1563 1564 BUG_ON(!th->t_trans_id); 1565 1566 init_tb_struct(th, &s_cut_balance, p_s_inode->i_sb, p_s_path, 1567 n_cut_size); 1568 1569 /* Repeat this loop until we either cut the item without needing 1570 to balance, or we fix_nodes without schedule occurring */ 1571 while (1) { 1572 /* Determine the balance mode, position of the first byte to 1573 be cut, and size to be cut. In case of the indirect item 1574 free unformatted nodes which are pointed to by the cut 1575 pointers. */ 1576 1577 c_mode = 1578 prepare_for_delete_or_cut(th, p_s_inode, p_s_path, 1579 p_s_item_key, &n_removed, 1580 &n_cut_size, n_new_file_size); 1581 if (c_mode == M_CONVERT) { 1582 /* convert last unformatted node to direct item or leave 1583 tail in the unformatted node */ 1584 RFALSE(n_ret_value != CARRY_ON, 1585 "PAP-5570: can not convert twice"); 1586 1587 n_ret_value = 1588 maybe_indirect_to_direct(th, p_s_inode, page, 1589 p_s_path, p_s_item_key, 1590 n_new_file_size, &c_mode); 1591 if (c_mode == M_SKIP_BALANCING) 1592 /* tail has been left in the unformatted node */ 1593 return n_ret_value; 1594 1595 n_is_inode_locked = 1; 1596 1597 /* removing of last unformatted node will change value we 1598 have to return to truncate. Save it */ 1599 retval2 = n_ret_value; 1600 /*retval2 = p_s_sb->s_blocksize - (n_new_file_size & (p_s_sb->s_blocksize - 1)); */ 1601 1602 /* So, we have performed the first part of the conversion: 1603 inserting the new direct item. Now we are removing the 1604 last unformatted node pointer. Set key to search for 1605 it. */ 1606 set_cpu_key_k_type(p_s_item_key, TYPE_INDIRECT); 1607 p_s_item_key->key_length = 4; 1608 n_new_file_size -= 1609 (n_new_file_size & (p_s_sb->s_blocksize - 1)); 1610 tail_pos = n_new_file_size; 1611 set_cpu_key_k_offset(p_s_item_key, n_new_file_size + 1); 1612 if (search_for_position_by_key 1613 (p_s_sb, p_s_item_key, 1614 p_s_path) == POSITION_NOT_FOUND) { 1615 print_block(PATH_PLAST_BUFFER(p_s_path), 3, 1616 PATH_LAST_POSITION(p_s_path) - 1, 1617 PATH_LAST_POSITION(p_s_path) + 1); 1618 reiserfs_panic(p_s_sb, 1619 "PAP-5580: reiserfs_cut_from_item: item to convert does not exist (%K)", 1620 p_s_item_key); 1621 } 1622 continue; 1623 } 1624 if (n_cut_size == 0) { 1625 pathrelse(p_s_path); 1626 return 0; 1627 } 1628 1629 s_cut_balance.insert_size[0] = n_cut_size; 1630 1631 n_ret_value = fix_nodes(c_mode, &s_cut_balance, NULL, NULL); 1632 if (n_ret_value != REPEAT_SEARCH) 1633 break; 1634 1635 PROC_INFO_INC(p_s_sb, cut_from_item_restarted); 1636 1637 n_ret_value = 1638 search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path); 1639 if (n_ret_value == POSITION_FOUND) 1640 continue; 1641 1642 reiserfs_warning(p_s_sb, 1643 "PAP-5610: reiserfs_cut_from_item: item %K not found", 1644 p_s_item_key); 1645 unfix_nodes(&s_cut_balance); 1646 return (n_ret_value == IO_ERROR) ? -EIO : -ENOENT; 1647 } /* while */ 1648 1649 // check fix_nodes results (IO_ERROR or NO_DISK_SPACE) 1650 if (n_ret_value != CARRY_ON) { 1651 if (n_is_inode_locked) { 1652 // FIXME: this seems to be not needed: we are always able 1653 // to cut item 1654 indirect_to_direct_roll_back(th, p_s_inode, p_s_path); 1655 } 1656 if (n_ret_value == NO_DISK_SPACE) 1657 reiserfs_warning(p_s_sb, "NO_DISK_SPACE"); 1658 unfix_nodes(&s_cut_balance); 1659 return -EIO; 1660 } 1661 1662 /* go ahead and perform balancing */ 1663 1664 RFALSE(c_mode == M_PASTE || c_mode == M_INSERT, "invalid mode"); 1665 1666 /* Calculate number of bytes that need to be cut from the item. */ 1667 quota_cut_bytes = 1668 (c_mode == 1669 M_DELETE) ? ih_item_len(get_ih(p_s_path)) : -s_cut_balance. 1670 insert_size[0]; 1671 if (retval2 == -1) 1672 n_ret_value = calc_deleted_bytes_number(&s_cut_balance, c_mode); 1673 else 1674 n_ret_value = retval2; 1675 1676 /* For direct items, we only change the quota when deleting the last 1677 ** item. 1678 */ 1679 p_le_ih = PATH_PITEM_HEAD(s_cut_balance.tb_path); 1680 if (!S_ISLNK(p_s_inode->i_mode) && is_direct_le_ih(p_le_ih)) { 1681 if (c_mode == M_DELETE && 1682 (le_ih_k_offset(p_le_ih) & (p_s_sb->s_blocksize - 1)) == 1683 1) { 1684 // FIXME: this is to keep 3.5 happy 1685 REISERFS_I(p_s_inode)->i_first_direct_byte = U32_MAX; 1686 quota_cut_bytes = p_s_sb->s_blocksize + UNFM_P_SIZE; 1687 } else { 1688 quota_cut_bytes = 0; 1689 } 1690 } 1691 #ifdef CONFIG_REISERFS_CHECK 1692 if (n_is_inode_locked) { 1693 struct item_head *le_ih = 1694 PATH_PITEM_HEAD(s_cut_balance.tb_path); 1695 /* we are going to complete indirect2direct conversion. Make 1696 sure, that we exactly remove last unformatted node pointer 1697 of the item */ 1698 if (!is_indirect_le_ih(le_ih)) 1699 reiserfs_panic(p_s_sb, 1700 "vs-5652: reiserfs_cut_from_item: " 1701 "item must be indirect %h", le_ih); 1702 1703 if (c_mode == M_DELETE && ih_item_len(le_ih) != UNFM_P_SIZE) 1704 reiserfs_panic(p_s_sb, 1705 "vs-5653: reiserfs_cut_from_item: " 1706 "completing indirect2direct conversion indirect item %h " 1707 "being deleted must be of 4 byte long", 1708 le_ih); 1709 1710 if (c_mode == M_CUT 1711 && s_cut_balance.insert_size[0] != -UNFM_P_SIZE) { 1712 reiserfs_panic(p_s_sb, 1713 "vs-5654: reiserfs_cut_from_item: " 1714 "can not complete indirect2direct conversion of %h (CUT, insert_size==%d)", 1715 le_ih, s_cut_balance.insert_size[0]); 1716 } 1717 /* it would be useful to make sure, that right neighboring 1718 item is direct item of this file */ 1719 } 1720 #endif 1721 1722 do_balance(&s_cut_balance, NULL, NULL, c_mode); 1723 if (n_is_inode_locked) { 1724 /* we've done an indirect->direct conversion. when the data block 1725 ** was freed, it was removed from the list of blocks that must 1726 ** be flushed before the transaction commits, make sure to 1727 ** unmap and invalidate it 1728 */ 1729 unmap_buffers(page, tail_pos); 1730 REISERFS_I(p_s_inode)->i_flags &= ~i_pack_on_close_mask; 1731 } 1732 #ifdef REISERQUOTA_DEBUG 1733 reiserfs_debug(p_s_inode->i_sb, REISERFS_DEBUG_CODE, 1734 "reiserquota cut_from_item(): freeing %u id=%u type=%c", 1735 quota_cut_bytes, p_s_inode->i_uid, '?'); 1736 #endif 1737 DQUOT_FREE_SPACE_NODIRTY(p_s_inode, quota_cut_bytes); 1738 return n_ret_value; 1739 } 1740 1741 static void truncate_directory(struct reiserfs_transaction_handle *th, 1742 struct inode *inode) 1743 { 1744 BUG_ON(!th->t_trans_id); 1745 if (inode->i_nlink) 1746 reiserfs_warning(inode->i_sb, 1747 "vs-5655: truncate_directory: link count != 0"); 1748 1749 set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), DOT_OFFSET); 1750 set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_DIRENTRY); 1751 reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode)); 1752 reiserfs_update_sd(th, inode); 1753 set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), SD_OFFSET); 1754 set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_STAT_DATA); 1755 } 1756 1757 /* Truncate file to the new size. Note, this must be called with a transaction 1758 already started */ 1759 int reiserfs_do_truncate(struct reiserfs_transaction_handle *th, struct inode *p_s_inode, /* ->i_size contains new 1760 size */ 1761 struct page *page, /* up to date for last block */ 1762 int update_timestamps /* when it is called by 1763 file_release to convert 1764 the tail - no timestamps 1765 should be updated */ 1766 ) 1767 { 1768 INITIALIZE_PATH(s_search_path); /* Path to the current object item. */ 1769 struct item_head *p_le_ih; /* Pointer to an item header. */ 1770 struct cpu_key s_item_key; /* Key to search for a previous file item. */ 1771 loff_t n_file_size, /* Old file size. */ 1772 n_new_file_size; /* New file size. */ 1773 int n_deleted; /* Number of deleted or truncated bytes. */ 1774 int retval; 1775 int err = 0; 1776 1777 BUG_ON(!th->t_trans_id); 1778 if (! 1779 (S_ISREG(p_s_inode->i_mode) || S_ISDIR(p_s_inode->i_mode) 1780 || S_ISLNK(p_s_inode->i_mode))) 1781 return 0; 1782 1783 if (S_ISDIR(p_s_inode->i_mode)) { 1784 // deletion of directory - no need to update timestamps 1785 truncate_directory(th, p_s_inode); 1786 return 0; 1787 } 1788 1789 /* Get new file size. */ 1790 n_new_file_size = p_s_inode->i_size; 1791 1792 // FIXME: note, that key type is unimportant here 1793 make_cpu_key(&s_item_key, p_s_inode, max_reiserfs_offset(p_s_inode), 1794 TYPE_DIRECT, 3); 1795 1796 retval = 1797 search_for_position_by_key(p_s_inode->i_sb, &s_item_key, 1798 &s_search_path); 1799 if (retval == IO_ERROR) { 1800 reiserfs_warning(p_s_inode->i_sb, 1801 "vs-5657: reiserfs_do_truncate: " 1802 "i/o failure occurred trying to truncate %K", 1803 &s_item_key); 1804 err = -EIO; 1805 goto out; 1806 } 1807 if (retval == POSITION_FOUND || retval == FILE_NOT_FOUND) { 1808 reiserfs_warning(p_s_inode->i_sb, 1809 "PAP-5660: reiserfs_do_truncate: " 1810 "wrong result %d of search for %K", retval, 1811 &s_item_key); 1812 1813 err = -EIO; 1814 goto out; 1815 } 1816 1817 s_search_path.pos_in_item--; 1818 1819 /* Get real file size (total length of all file items) */ 1820 p_le_ih = PATH_PITEM_HEAD(&s_search_path); 1821 if (is_statdata_le_ih(p_le_ih)) 1822 n_file_size = 0; 1823 else { 1824 loff_t offset = le_ih_k_offset(p_le_ih); 1825 int bytes = 1826 op_bytes_number(p_le_ih, p_s_inode->i_sb->s_blocksize); 1827 1828 /* this may mismatch with real file size: if last direct item 1829 had no padding zeros and last unformatted node had no free 1830 space, this file would have this file size */ 1831 n_file_size = offset + bytes - 1; 1832 } 1833 /* 1834 * are we doing a full truncate or delete, if so 1835 * kick in the reada code 1836 */ 1837 if (n_new_file_size == 0) 1838 s_search_path.reada = PATH_READA | PATH_READA_BACK; 1839 1840 if (n_file_size == 0 || n_file_size < n_new_file_size) { 1841 goto update_and_out; 1842 } 1843 1844 /* Update key to search for the last file item. */ 1845 set_cpu_key_k_offset(&s_item_key, n_file_size); 1846 1847 do { 1848 /* Cut or delete file item. */ 1849 n_deleted = 1850 reiserfs_cut_from_item(th, &s_search_path, &s_item_key, 1851 p_s_inode, page, n_new_file_size); 1852 if (n_deleted < 0) { 1853 reiserfs_warning(p_s_inode->i_sb, 1854 "vs-5665: reiserfs_do_truncate: reiserfs_cut_from_item failed"); 1855 reiserfs_check_path(&s_search_path); 1856 return 0; 1857 } 1858 1859 RFALSE(n_deleted > n_file_size, 1860 "PAP-5670: reiserfs_cut_from_item: too many bytes deleted: deleted %d, file_size %lu, item_key %K", 1861 n_deleted, n_file_size, &s_item_key); 1862 1863 /* Change key to search the last file item. */ 1864 n_file_size -= n_deleted; 1865 1866 set_cpu_key_k_offset(&s_item_key, n_file_size); 1867 1868 /* While there are bytes to truncate and previous file item is presented in the tree. */ 1869 1870 /* 1871 ** This loop could take a really long time, and could log 1872 ** many more blocks than a transaction can hold. So, we do a polite 1873 ** journal end here, and if the transaction needs ending, we make 1874 ** sure the file is consistent before ending the current trans 1875 ** and starting a new one 1876 */ 1877 if (journal_transaction_should_end(th, 0) || 1878 reiserfs_transaction_free_space(th) <= JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD) { 1879 int orig_len_alloc = th->t_blocks_allocated; 1880 decrement_counters_in_path(&s_search_path); 1881 1882 if (update_timestamps) { 1883 p_s_inode->i_mtime = p_s_inode->i_ctime = 1884 CURRENT_TIME_SEC; 1885 } 1886 reiserfs_update_sd(th, p_s_inode); 1887 1888 err = journal_end(th, p_s_inode->i_sb, orig_len_alloc); 1889 if (err) 1890 goto out; 1891 err = journal_begin(th, p_s_inode->i_sb, 1892 JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD + JOURNAL_PER_BALANCE_CNT * 4) ; 1893 if (err) 1894 goto out; 1895 reiserfs_update_inode_transaction(p_s_inode); 1896 } 1897 } while (n_file_size > ROUND_UP(n_new_file_size) && 1898 search_for_position_by_key(p_s_inode->i_sb, &s_item_key, 1899 &s_search_path) == POSITION_FOUND); 1900 1901 RFALSE(n_file_size > ROUND_UP(n_new_file_size), 1902 "PAP-5680: truncate did not finish: new_file_size %Ld, current %Ld, oid %d", 1903 n_new_file_size, n_file_size, s_item_key.on_disk_key.k_objectid); 1904 1905 update_and_out: 1906 if (update_timestamps) { 1907 // this is truncate, not file closing 1908 p_s_inode->i_mtime = p_s_inode->i_ctime = CURRENT_TIME_SEC; 1909 } 1910 reiserfs_update_sd(th, p_s_inode); 1911 1912 out: 1913 pathrelse(&s_search_path); 1914 return err; 1915 } 1916 1917 #ifdef CONFIG_REISERFS_CHECK 1918 // this makes sure, that we __append__, not overwrite or add holes 1919 static void check_research_for_paste(struct treepath *path, 1920 const struct cpu_key *p_s_key) 1921 { 1922 struct item_head *found_ih = get_ih(path); 1923 1924 if (is_direct_le_ih(found_ih)) { 1925 if (le_ih_k_offset(found_ih) + 1926 op_bytes_number(found_ih, 1927 get_last_bh(path)->b_size) != 1928 cpu_key_k_offset(p_s_key) 1929 || op_bytes_number(found_ih, 1930 get_last_bh(path)->b_size) != 1931 pos_in_item(path)) 1932 reiserfs_panic(NULL, 1933 "PAP-5720: check_research_for_paste: " 1934 "found direct item %h or position (%d) does not match to key %K", 1935 found_ih, pos_in_item(path), p_s_key); 1936 } 1937 if (is_indirect_le_ih(found_ih)) { 1938 if (le_ih_k_offset(found_ih) + 1939 op_bytes_number(found_ih, 1940 get_last_bh(path)->b_size) != 1941 cpu_key_k_offset(p_s_key) 1942 || I_UNFM_NUM(found_ih) != pos_in_item(path) 1943 || get_ih_free_space(found_ih) != 0) 1944 reiserfs_panic(NULL, 1945 "PAP-5730: check_research_for_paste: " 1946 "found indirect item (%h) or position (%d) does not match to key (%K)", 1947 found_ih, pos_in_item(path), p_s_key); 1948 } 1949 } 1950 #endif /* config reiserfs check */ 1951 1952 /* Paste bytes to the existing item. Returns bytes number pasted into the item. */ 1953 int reiserfs_paste_into_item(struct reiserfs_transaction_handle *th, struct treepath *p_s_search_path, /* Path to the pasted item. */ 1954 const struct cpu_key *p_s_key, /* Key to search for the needed item. */ 1955 struct inode *inode, /* Inode item belongs to */ 1956 const char *p_c_body, /* Pointer to the bytes to paste. */ 1957 int n_pasted_size) 1958 { /* Size of pasted bytes. */ 1959 struct tree_balance s_paste_balance; 1960 int retval; 1961 int fs_gen; 1962 1963 BUG_ON(!th->t_trans_id); 1964 1965 fs_gen = get_generation(inode->i_sb); 1966 1967 #ifdef REISERQUOTA_DEBUG 1968 reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE, 1969 "reiserquota paste_into_item(): allocating %u id=%u type=%c", 1970 n_pasted_size, inode->i_uid, 1971 key2type(&(p_s_key->on_disk_key))); 1972 #endif 1973 1974 if (DQUOT_ALLOC_SPACE_NODIRTY(inode, n_pasted_size)) { 1975 pathrelse(p_s_search_path); 1976 return -EDQUOT; 1977 } 1978 init_tb_struct(th, &s_paste_balance, th->t_super, p_s_search_path, 1979 n_pasted_size); 1980 #ifdef DISPLACE_NEW_PACKING_LOCALITIES 1981 s_paste_balance.key = p_s_key->on_disk_key; 1982 #endif 1983 1984 /* DQUOT_* can schedule, must check before the fix_nodes */ 1985 if (fs_changed(fs_gen, inode->i_sb)) { 1986 goto search_again; 1987 } 1988 1989 while ((retval = 1990 fix_nodes(M_PASTE, &s_paste_balance, NULL, 1991 p_c_body)) == REPEAT_SEARCH) { 1992 search_again: 1993 /* file system changed while we were in the fix_nodes */ 1994 PROC_INFO_INC(th->t_super, paste_into_item_restarted); 1995 retval = 1996 search_for_position_by_key(th->t_super, p_s_key, 1997 p_s_search_path); 1998 if (retval == IO_ERROR) { 1999 retval = -EIO; 2000 goto error_out; 2001 } 2002 if (retval == POSITION_FOUND) { 2003 reiserfs_warning(inode->i_sb, 2004 "PAP-5710: reiserfs_paste_into_item: entry or pasted byte (%K) exists", 2005 p_s_key); 2006 retval = -EEXIST; 2007 goto error_out; 2008 } 2009 #ifdef CONFIG_REISERFS_CHECK 2010 check_research_for_paste(p_s_search_path, p_s_key); 2011 #endif 2012 } 2013 2014 /* Perform balancing after all resources are collected by fix_nodes, and 2015 accessing them will not risk triggering schedule. */ 2016 if (retval == CARRY_ON) { 2017 do_balance(&s_paste_balance, NULL /*ih */ , p_c_body, M_PASTE); 2018 return 0; 2019 } 2020 retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO; 2021 error_out: 2022 /* this also releases the path */ 2023 unfix_nodes(&s_paste_balance); 2024 #ifdef REISERQUOTA_DEBUG 2025 reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE, 2026 "reiserquota paste_into_item(): freeing %u id=%u type=%c", 2027 n_pasted_size, inode->i_uid, 2028 key2type(&(p_s_key->on_disk_key))); 2029 #endif 2030 DQUOT_FREE_SPACE_NODIRTY(inode, n_pasted_size); 2031 return retval; 2032 } 2033 2034 /* Insert new item into the buffer at the path. */ 2035 int reiserfs_insert_item(struct reiserfs_transaction_handle *th, struct treepath *p_s_path, /* Path to the inserteded item. */ 2036 const struct cpu_key *key, struct item_head *p_s_ih, /* Pointer to the item header to insert. */ 2037 struct inode *inode, const char *p_c_body) 2038 { /* Pointer to the bytes to insert. */ 2039 struct tree_balance s_ins_balance; 2040 int retval; 2041 int fs_gen = 0; 2042 int quota_bytes = 0; 2043 2044 BUG_ON(!th->t_trans_id); 2045 2046 if (inode) { /* Do we count quotas for item? */ 2047 fs_gen = get_generation(inode->i_sb); 2048 quota_bytes = ih_item_len(p_s_ih); 2049 2050 /* hack so the quota code doesn't have to guess if the file has 2051 ** a tail, links are always tails, so there's no guessing needed 2052 */ 2053 if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(p_s_ih)) { 2054 quota_bytes = inode->i_sb->s_blocksize + UNFM_P_SIZE; 2055 } 2056 #ifdef REISERQUOTA_DEBUG 2057 reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE, 2058 "reiserquota insert_item(): allocating %u id=%u type=%c", 2059 quota_bytes, inode->i_uid, head2type(p_s_ih)); 2060 #endif 2061 /* We can't dirty inode here. It would be immediately written but 2062 * appropriate stat item isn't inserted yet... */ 2063 if (DQUOT_ALLOC_SPACE_NODIRTY(inode, quota_bytes)) { 2064 pathrelse(p_s_path); 2065 return -EDQUOT; 2066 } 2067 } 2068 init_tb_struct(th, &s_ins_balance, th->t_super, p_s_path, 2069 IH_SIZE + ih_item_len(p_s_ih)); 2070 #ifdef DISPLACE_NEW_PACKING_LOCALITIES 2071 s_ins_balance.key = key->on_disk_key; 2072 #endif 2073 /* DQUOT_* can schedule, must check to be sure calling fix_nodes is safe */ 2074 if (inode && fs_changed(fs_gen, inode->i_sb)) { 2075 goto search_again; 2076 } 2077 2078 while ((retval = 2079 fix_nodes(M_INSERT, &s_ins_balance, p_s_ih, 2080 p_c_body)) == REPEAT_SEARCH) { 2081 search_again: 2082 /* file system changed while we were in the fix_nodes */ 2083 PROC_INFO_INC(th->t_super, insert_item_restarted); 2084 retval = search_item(th->t_super, key, p_s_path); 2085 if (retval == IO_ERROR) { 2086 retval = -EIO; 2087 goto error_out; 2088 } 2089 if (retval == ITEM_FOUND) { 2090 reiserfs_warning(th->t_super, 2091 "PAP-5760: reiserfs_insert_item: " 2092 "key %K already exists in the tree", 2093 key); 2094 retval = -EEXIST; 2095 goto error_out; 2096 } 2097 } 2098 2099 /* make balancing after all resources will be collected at a time */ 2100 if (retval == CARRY_ON) { 2101 do_balance(&s_ins_balance, p_s_ih, p_c_body, M_INSERT); 2102 return 0; 2103 } 2104 2105 retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO; 2106 error_out: 2107 /* also releases the path */ 2108 unfix_nodes(&s_ins_balance); 2109 #ifdef REISERQUOTA_DEBUG 2110 reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE, 2111 "reiserquota insert_item(): freeing %u id=%u type=%c", 2112 quota_bytes, inode->i_uid, head2type(p_s_ih)); 2113 #endif 2114 if (inode) 2115 DQUOT_FREE_SPACE_NODIRTY(inode, quota_bytes); 2116 return retval; 2117 } 2118