do_balan.c revision 7f447ba825a0752c0450ebd129f187484e86fe8b
1/* 2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README 3 */ 4 5/* 6 * Now we have all buffers that must be used in balancing of the tree 7 * Further calculations can not cause schedule(), and thus the buffer 8 * tree will be stable until the balancing will be finished 9 * balance the tree according to the analysis made before, 10 * and using buffers obtained after all above. 11 */ 12 13#include <asm/uaccess.h> 14#include <linux/time.h> 15#include "reiserfs.h" 16#include <linux/buffer_head.h> 17#include <linux/kernel.h> 18 19static inline void buffer_info_init_left(struct tree_balance *tb, 20 struct buffer_info *bi) 21{ 22 bi->tb = tb; 23 bi->bi_bh = tb->L[0]; 24 bi->bi_parent = tb->FL[0]; 25 bi->bi_position = get_left_neighbor_position(tb, 0); 26} 27 28static inline void buffer_info_init_right(struct tree_balance *tb, 29 struct buffer_info *bi) 30{ 31 bi->tb = tb; 32 bi->bi_bh = tb->R[0]; 33 bi->bi_parent = tb->FR[0]; 34 bi->bi_position = get_right_neighbor_position(tb, 0); 35} 36 37static inline void buffer_info_init_tbS0(struct tree_balance *tb, 38 struct buffer_info *bi) 39{ 40 bi->tb = tb; 41 bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path); 42 bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0); 43 bi->bi_position = PATH_H_POSITION(tb->tb_path, 1); 44} 45 46static inline void buffer_info_init_bh(struct tree_balance *tb, 47 struct buffer_info *bi, 48 struct buffer_head *bh) 49{ 50 bi->tb = tb; 51 bi->bi_bh = bh; 52 bi->bi_parent = NULL; 53 bi->bi_position = 0; 54} 55 56inline void do_balance_mark_leaf_dirty(struct tree_balance *tb, 57 struct buffer_head *bh, int flag) 58{ 59 journal_mark_dirty(tb->transaction_handle, bh); 60} 61 62#define do_balance_mark_internal_dirty do_balance_mark_leaf_dirty 63#define do_balance_mark_sb_dirty do_balance_mark_leaf_dirty 64 65/* 66 * summary: 67 * if deleting something ( tb->insert_size[0] < 0 ) 68 * return(balance_leaf_when_delete()); (flag d handled here) 69 * else 70 * if lnum is larger than 0 we put items into the left node 71 * if rnum is larger than 0 we put items into the right node 72 * if snum1 is larger than 0 we put items into the new node s1 73 * if snum2 is larger than 0 we put items into the new node s2 74 * Note that all *num* count new items being created. 75 * 76 * It would be easier to read balance_leaf() if each of these summary 77 * lines was a separate procedure rather than being inlined. I think 78 * that there are many passages here and in balance_leaf_when_delete() in 79 * which two calls to one procedure can replace two passages, and it 80 * might save cache space and improve software maintenance costs to do so. 81 * 82 * Vladimir made the perceptive comment that we should offload most of 83 * the decision making in this function into fix_nodes/check_balance, and 84 * then create some sort of structure in tb that says what actions should 85 * be performed by do_balance. 86 * 87 * -Hans 88 */ 89 90/* 91 * Balance leaf node in case of delete or cut: insert_size[0] < 0 92 * 93 * lnum, rnum can have values >= -1 94 * -1 means that the neighbor must be joined with S 95 * 0 means that nothing should be done with the neighbor 96 * >0 means to shift entirely or partly the specified number of items 97 * to the neighbor 98 */ 99static int balance_leaf_when_delete(struct tree_balance *tb, int flag) 100{ 101 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 102 int item_pos = PATH_LAST_POSITION(tb->tb_path); 103 int pos_in_item = tb->tb_path->pos_in_item; 104 struct buffer_info bi; 105 int n; 106 struct item_head *ih; 107 108 RFALSE(tb->FR[0] && B_LEVEL(tb->FR[0]) != DISK_LEAF_NODE_LEVEL + 1, 109 "vs- 12000: level: wrong FR %z", tb->FR[0]); 110 RFALSE(tb->blknum[0] > 1, 111 "PAP-12005: tb->blknum == %d, can not be > 1", tb->blknum[0]); 112 RFALSE(!tb->blknum[0] && !PATH_H_PPARENT(tb->tb_path, 0), 113 "PAP-12010: tree can not be empty"); 114 115 ih = item_head(tbS0, item_pos); 116 buffer_info_init_tbS0(tb, &bi); 117 118 /* Delete or truncate the item */ 119 120 switch (flag) { 121 case M_DELETE: /* delete item in S[0] */ 122 123 RFALSE(ih_item_len(ih) + IH_SIZE != -tb->insert_size[0], 124 "vs-12013: mode Delete, insert size %d, ih to be deleted %h", 125 -tb->insert_size[0], ih); 126 127 leaf_delete_items(&bi, 0, item_pos, 1, -1); 128 129 if (!item_pos && tb->CFL[0]) { 130 if (B_NR_ITEMS(tbS0)) { 131 replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 132 0); 133 } else { 134 if (!PATH_H_POSITION(tb->tb_path, 1)) 135 replace_key(tb, tb->CFL[0], tb->lkey[0], 136 PATH_H_PPARENT(tb->tb_path, 137 0), 0); 138 } 139 } 140 141 RFALSE(!item_pos && !tb->CFL[0], 142 "PAP-12020: tb->CFL[0]==%p, tb->L[0]==%p", tb->CFL[0], 143 tb->L[0]); 144 145 break; 146 147 case M_CUT:{ /* cut item in S[0] */ 148 if (is_direntry_le_ih(ih)) { 149 150 /* 151 * UFS unlink semantics are such that you 152 * can only delete one directory entry at 153 * a time. 154 */ 155 156 /* 157 * when we cut a directory tb->insert_size[0] 158 * means number of entries to be cut (always 1) 159 */ 160 tb->insert_size[0] = -1; 161 leaf_cut_from_buffer(&bi, item_pos, pos_in_item, 162 -tb->insert_size[0]); 163 164 RFALSE(!item_pos && !pos_in_item && !tb->CFL[0], 165 "PAP-12030: can not change delimiting key. CFL[0]=%p", 166 tb->CFL[0]); 167 168 if (!item_pos && !pos_in_item && tb->CFL[0]) { 169 replace_key(tb, tb->CFL[0], tb->lkey[0], 170 tbS0, 0); 171 } 172 } else { 173 leaf_cut_from_buffer(&bi, item_pos, pos_in_item, 174 -tb->insert_size[0]); 175 176 RFALSE(!ih_item_len(ih), 177 "PAP-12035: cut must leave non-zero dynamic length of item"); 178 } 179 break; 180 } 181 182 default: 183 print_cur_tb("12040"); 184 reiserfs_panic(tb->tb_sb, "PAP-12040", 185 "unexpected mode: %s(%d)", 186 (flag == 187 M_PASTE) ? "PASTE" : ((flag == 188 M_INSERT) ? "INSERT" : 189 "UNKNOWN"), flag); 190 } 191 192 /* 193 * the rule is that no shifting occurs unless by shifting 194 * a node can be freed 195 */ 196 n = B_NR_ITEMS(tbS0); 197 /* L[0] takes part in balancing */ 198 if (tb->lnum[0]) { 199 /* L[0] must be joined with S[0] */ 200 if (tb->lnum[0] == -1) { 201 /* R[0] must be also joined with S[0] */ 202 if (tb->rnum[0] == -1) { 203 if (tb->FR[0] == PATH_H_PPARENT(tb->tb_path, 0)) { 204 /* 205 * all contents of all the 3 buffers 206 * will be in L[0] 207 */ 208 if (PATH_H_POSITION(tb->tb_path, 1) == 0 209 && 1 < B_NR_ITEMS(tb->FR[0])) 210 replace_key(tb, tb->CFL[0], 211 tb->lkey[0], 212 tb->FR[0], 1); 213 214 leaf_move_items(LEAF_FROM_S_TO_L, tb, n, 215 -1, NULL); 216 leaf_move_items(LEAF_FROM_R_TO_L, tb, 217 B_NR_ITEMS(tb->R[0]), 218 -1, NULL); 219 220 reiserfs_invalidate_buffer(tb, tbS0); 221 reiserfs_invalidate_buffer(tb, 222 tb->R[0]); 223 224 return 0; 225 } 226 /* 227 * all contents of all the 3 buffers will 228 * be in R[0] 229 */ 230 leaf_move_items(LEAF_FROM_S_TO_R, tb, n, -1, 231 NULL); 232 leaf_move_items(LEAF_FROM_L_TO_R, tb, 233 B_NR_ITEMS(tb->L[0]), -1, NULL); 234 235 /* right_delimiting_key is correct in R[0] */ 236 replace_key(tb, tb->CFR[0], tb->rkey[0], 237 tb->R[0], 0); 238 239 reiserfs_invalidate_buffer(tb, tbS0); 240 reiserfs_invalidate_buffer(tb, tb->L[0]); 241 242 return -1; 243 } 244 245 RFALSE(tb->rnum[0] != 0, 246 "PAP-12045: rnum must be 0 (%d)", tb->rnum[0]); 247 /* all contents of L[0] and S[0] will be in L[0] */ 248 leaf_shift_left(tb, n, -1); 249 250 reiserfs_invalidate_buffer(tb, tbS0); 251 252 return 0; 253 } 254 255 /* 256 * a part of contents of S[0] will be in L[0] and the 257 * rest part of S[0] will be in R[0] 258 */ 259 260 RFALSE((tb->lnum[0] + tb->rnum[0] < n) || 261 (tb->lnum[0] + tb->rnum[0] > n + 1), 262 "PAP-12050: rnum(%d) and lnum(%d) and item number(%d) in S[0] are not consistent", 263 tb->rnum[0], tb->lnum[0], n); 264 RFALSE((tb->lnum[0] + tb->rnum[0] == n) && 265 (tb->lbytes != -1 || tb->rbytes != -1), 266 "PAP-12055: bad rbytes (%d)/lbytes (%d) parameters when items are not split", 267 tb->rbytes, tb->lbytes); 268 RFALSE((tb->lnum[0] + tb->rnum[0] == n + 1) && 269 (tb->lbytes < 1 || tb->rbytes != -1), 270 "PAP-12060: bad rbytes (%d)/lbytes (%d) parameters when items are split", 271 tb->rbytes, tb->lbytes); 272 273 leaf_shift_left(tb, tb->lnum[0], tb->lbytes); 274 leaf_shift_right(tb, tb->rnum[0], tb->rbytes); 275 276 reiserfs_invalidate_buffer(tb, tbS0); 277 278 return 0; 279 } 280 281 if (tb->rnum[0] == -1) { 282 /* all contents of R[0] and S[0] will be in R[0] */ 283 leaf_shift_right(tb, n, -1); 284 reiserfs_invalidate_buffer(tb, tbS0); 285 return 0; 286 } 287 288 RFALSE(tb->rnum[0], 289 "PAP-12065: bad rnum parameter must be 0 (%d)", tb->rnum[0]); 290 return 0; 291} 292 293static void balance_leaf_insert_left(struct tree_balance *tb, 294 struct item_head *ih, const char *body) 295{ 296 int ret_val; 297 struct buffer_info bi; 298 int n = B_NR_ITEMS(tb->L[0]); 299 300 if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1) { 301 /* part of new item falls into L[0] */ 302 int new_item_len; 303 int version; 304 305 ret_val = leaf_shift_left(tb, tb->lnum[0] - 1, -1); 306 307 /* Calculate item length to insert to S[0] */ 308 new_item_len = ih_item_len(ih) - tb->lbytes; 309 /* Calculate and check item length to insert to L[0] */ 310 put_ih_item_len(ih, ih_item_len(ih) - new_item_len); 311 312 RFALSE(ih_item_len(ih) <= 0, 313 "PAP-12080: there is nothing to insert into L[0]: ih_item_len=%d", 314 ih_item_len(ih)); 315 316 /* Insert new item into L[0] */ 317 buffer_info_init_left(tb, &bi); 318 leaf_insert_into_buf(&bi, 319 n + tb->item_pos - ret_val, ih, body, 320 tb->zeroes_num > ih_item_len(ih) ? ih_item_len(ih) : tb->zeroes_num); 321 322 version = ih_version(ih); 323 324 /* Calculate key component, item length and body to insert into S[0] */ 325 set_le_ih_k_offset(ih, le_ih_k_offset(ih) + 326 (tb->lbytes << (is_indirect_le_ih(ih) ? tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT : 0))); 327 328 put_ih_item_len(ih, new_item_len); 329 if (tb->lbytes > tb->zeroes_num) { 330 body += (tb->lbytes - tb->zeroes_num); 331 tb->zeroes_num = 0; 332 } else 333 tb->zeroes_num -= tb->lbytes; 334 335 RFALSE(ih_item_len(ih) <= 0, 336 "PAP-12085: there is nothing to insert into S[0]: ih_item_len=%d", 337 ih_item_len(ih)); 338 } else { 339 /* new item in whole falls into L[0] */ 340 /* Shift lnum[0]-1 items to L[0] */ 341 ret_val = leaf_shift_left(tb, tb->lnum[0] - 1, tb->lbytes); 342 /* Insert new item into L[0] */ 343 buffer_info_init_left(tb, &bi); 344 leaf_insert_into_buf(&bi, n + tb->item_pos - ret_val, ih, body, tb->zeroes_num); 345 tb->insert_size[0] = 0; 346 tb->zeroes_num = 0; 347 } 348 349} 350 351static void balance_leaf_paste_left(struct tree_balance *tb, 352 struct item_head *ih, const char *body) 353{ 354 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 355 int ret_val; 356 struct buffer_info bi; 357 int n = B_NR_ITEMS(tb->L[0]); 358 359 if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1) { 360 /* we must shift the part of the appended item */ 361 if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) { 362 363 RFALSE(tb->zeroes_num, 364 "PAP-12090: invalid parameter in case of a directory"); 365 /* directory item */ 366 if (tb->lbytes > tb->pos_in_item) { 367 /* new directory entry falls into L[0] */ 368 struct item_head *pasted; 369 int l_pos_in_item = tb->pos_in_item; 370 371 /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 entries from given directory item */ 372 ret_val = leaf_shift_left(tb, tb->lnum[0], tb->lbytes-1); 373 if (ret_val && !tb->item_pos) { 374 pasted = item_head(tb->L[0], B_NR_ITEMS(tb->L[0]) - 1); 375 l_pos_in_item += ih_entry_count(pasted) - (tb->lbytes -1); 376 } 377 378 /* Append given directory entry to directory item */ 379 buffer_info_init_left(tb, &bi); 380 leaf_paste_in_buffer(&bi, n + tb->item_pos - ret_val, l_pos_in_item, tb->insert_size[0], body, tb->zeroes_num); 381 382 /* previous string prepared space for pasting new entry, following string pastes this entry */ 383 384 /* when we have merge directory item, pos_in_item has been changed too */ 385 386 /* paste new directory entry. 1 is entry number */ 387 leaf_paste_entries(&bi, n + tb->item_pos - ret_val, l_pos_in_item, 388 1, (struct reiserfs_de_head *) body, 389 body + DEH_SIZE, tb->insert_size[0]); 390 tb->insert_size[0] = 0; 391 } else { 392 /* new directory item doesn't fall into L[0] */ 393 /* Shift lnum[0]-1 items in whole. Shift lbytes directory entries from directory item number lnum[0] */ 394 leaf_shift_left(tb, tb->lnum[0], tb->lbytes); 395 } 396 /* Calculate new position to append in item body */ 397 tb->pos_in_item -= tb->lbytes; 398 } else { 399 /* regular object */ 400 RFALSE(tb->lbytes <= 0, "PAP-12095: there is nothing to shift to L[0]. lbytes=%d", tb->lbytes); 401 RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)), 402 "PAP-12100: incorrect position to paste: item_len=%d, pos_in_item=%d", 403 ih_item_len(item_head(tbS0, tb->item_pos)), tb->pos_in_item); 404 405 if (tb->lbytes >= tb->pos_in_item) { 406 /* appended item will be in L[0] in whole */ 407 int l_n; 408 409 /* this bytes number must be appended to the last item of L[h] */ 410 l_n = tb->lbytes - tb->pos_in_item; 411 412 /* Calculate new insert_size[0] */ 413 tb->insert_size[0] -= l_n; 414 415 RFALSE(tb->insert_size[0] <= 0, 416 "PAP-12105: there is nothing to paste into L[0]. insert_size=%d", 417 tb->insert_size[0]); 418 ret_val = leaf_shift_left(tb, tb->lnum[0], ih_item_len 419 (item_head(tbS0, tb->item_pos))); 420 /* Append to body of item in L[0] */ 421 buffer_info_init_left(tb, &bi); 422 leaf_paste_in_buffer 423 (&bi, n + tb->item_pos - ret_val, ih_item_len 424 (item_head(tb->L[0], n + tb->item_pos - ret_val)), 425 l_n, body, 426 tb->zeroes_num > l_n ? l_n : tb->zeroes_num); 427 /* 0-th item in S0 can be only of DIRECT type when l_n != 0 */ 428 { 429 int version; 430 int temp_l = l_n; 431 432 RFALSE(ih_item_len(item_head(tbS0, 0)), 433 "PAP-12106: item length must be 0"); 434 RFALSE(comp_short_le_keys(leaf_key(tbS0, 0), leaf_key 435 (tb->L[0], n + tb->item_pos - ret_val)), 436 "PAP-12107: items must be of the same file"); 437 if (is_indirect_le_ih(item_head(tb->L[0], n + tb->item_pos - ret_val))) { 438 temp_l = l_n << (tb->tb_sb-> s_blocksize_bits - UNFM_P_SHIFT); 439 } 440 /* update key of first item in S0 */ 441 version = ih_version(item_head(tbS0, 0)); 442 set_le_key_k_offset(version, leaf_key(tbS0, 0), 443 le_key_k_offset(version,leaf_key(tbS0, 0)) + temp_l); 444 /* update left delimiting key */ 445 set_le_key_k_offset(version, internal_key(tb->CFL[0], tb->lkey[0]), 446 le_key_k_offset(version, internal_key(tb->CFL[0], tb->lkey[0])) + temp_l); 447 } 448 449 /* Calculate new body, position in item and insert_size[0] */ 450 if (l_n > tb->zeroes_num) { 451 body += (l_n - tb->zeroes_num); 452 tb->zeroes_num = 0; 453 } else 454 tb->zeroes_num -= l_n; 455 tb->pos_in_item = 0; 456 457 RFALSE(comp_short_le_keys(leaf_key(tbS0, 0), leaf_key(tb->L[0], B_NR_ITEMS(tb->L[0]) - 1)) 458 || !op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size) 459 || !op_is_left_mergeable(internal_key(tb->CFL[0], tb->lkey[0]), tbS0->b_size), 460 "PAP-12120: item must be merge-able with left neighboring item"); 461 } else { /* only part of the appended item will be in L[0] */ 462 463 /* Calculate position in item for append in S[0] */ 464 tb->pos_in_item -= tb->lbytes; 465 466 RFALSE(tb->pos_in_item <= 0, "PAP-12125: no place for paste. pos_in_item=%d", tb->pos_in_item); 467 468 /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 byte from item number lnum[0] */ 469 leaf_shift_left(tb, tb->lnum[0], tb->lbytes); 470 } 471 } 472 } else { /* appended item will be in L[0] in whole */ 473 474 struct item_head *pasted; 475 476 if (!tb->item_pos && op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size)) { /* if we paste into first item of S[0] and it is left mergable */ 477 /* then increment pos_in_item by the size of the last item in L[0] */ 478 pasted = item_head(tb->L[0], n - 1); 479 if (is_direntry_le_ih(pasted)) 480 tb->pos_in_item += ih_entry_count(pasted); 481 else 482 tb->pos_in_item += ih_item_len(pasted); 483 } 484 485 /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 byte from item number lnum[0] */ 486 ret_val = leaf_shift_left(tb, tb->lnum[0], tb->lbytes); 487 /* Append to body of item in L[0] */ 488 buffer_info_init_left(tb, &bi); 489 leaf_paste_in_buffer(&bi, n + tb->item_pos - ret_val, 490 tb->pos_in_item, 491 tb->insert_size[0], 492 body, tb->zeroes_num); 493 494 /* if appended item is directory, paste entry */ 495 pasted = item_head(tb->L[0], n + tb->item_pos - ret_val); 496 if (is_direntry_le_ih(pasted)) 497 leaf_paste_entries(&bi, n + tb->item_pos - ret_val, 498 tb->pos_in_item, 1, 499 (struct reiserfs_de_head *) body, 500 body + DEH_SIZE, 501 tb->insert_size[0]); 502 /* if appended item is indirect item, put unformatted node into un list */ 503 if (is_indirect_le_ih(pasted)) 504 set_ih_free_space(pasted, 0); 505 tb->insert_size[0] = 0; 506 tb->zeroes_num = 0; 507 } 508 509} 510 511static void balance_leaf_insert_right(struct tree_balance *tb, 512 struct item_head *ih, const char *body) 513{ 514 515 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 516 int n = B_NR_ITEMS(tbS0); 517 struct buffer_info bi; 518 int ret_val; 519 if (n - tb->rnum[0] < tb->item_pos) { /* new item or its part falls to R[0] */ 520 if (tb->item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1) { /* part of new item falls into R[0] */ 521 loff_t old_key_comp, old_len, r_zeroes_number; 522 const char *r_body; 523 int version; 524 loff_t offset; 525 526 leaf_shift_right(tb, tb->rnum[0] - 1, -1); 527 528 version = ih_version(ih); 529 /* Remember key component and item length */ 530 old_key_comp = le_ih_k_offset(ih); 531 old_len = ih_item_len(ih); 532 533 /* Calculate key component and item length to insert into R[0] */ 534 offset = le_ih_k_offset(ih) + ((old_len - tb->rbytes) << (is_indirect_le_ih(ih) ? tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT : 0)); 535 set_le_ih_k_offset(ih, offset); 536 put_ih_item_len(ih, tb->rbytes); 537 /* Insert part of the item into R[0] */ 538 buffer_info_init_right(tb, &bi); 539 if ((old_len - tb->rbytes) > tb->zeroes_num) { 540 r_zeroes_number = 0; 541 r_body = body + (old_len - tb->rbytes) - tb->zeroes_num; 542 } else { 543 r_body = body; 544 r_zeroes_number = tb->zeroes_num - (old_len - tb->rbytes); 545 tb->zeroes_num -= r_zeroes_number; 546 } 547 548 leaf_insert_into_buf(&bi, 0, ih, r_body, 549 r_zeroes_number); 550 551 /* Replace right delimiting key by first key in R[0] */ 552 replace_key(tb, tb->CFR[0], tb->rkey[0], 553 tb->R[0], 0); 554 555 /* Calculate key component and item length to insert into S[0] */ 556 set_le_ih_k_offset(ih, old_key_comp); 557 put_ih_item_len(ih, old_len - tb->rbytes); 558 559 tb->insert_size[0] -= tb->rbytes; 560 561 } else { /* whole new item falls into R[0] */ 562 563 /* Shift rnum[0]-1 items to R[0] */ 564 ret_val = leaf_shift_right(tb, tb->rnum[0] - 1, tb->rbytes); 565 /* Insert new item into R[0] */ 566 buffer_info_init_right(tb, &bi); 567 leaf_insert_into_buf(&bi, tb->item_pos - n + tb->rnum[0] - 1, 568 ih, body, tb->zeroes_num); 569 570 if (tb->item_pos - n + tb->rnum[0] - 1 == 0) { 571 replace_key(tb, tb->CFR[0], 572 tb->rkey[0], 573 tb->R[0], 0); 574 575 } 576 tb->zeroes_num = tb->insert_size[0] = 0; 577 } 578 } else { /* new item or part of it doesn't fall into R[0] */ 579 580 leaf_shift_right(tb, tb->rnum[0], tb->rbytes); 581 } 582 583} 584 585static void balance_leaf_paste_right(struct tree_balance *tb, 586 struct item_head *ih, const char *body) 587{ 588 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 589 int n = B_NR_ITEMS(tbS0); 590 struct buffer_info bi; 591 int ret_val; 592 593 if (n - tb->rnum[0] <= tb->item_pos) { /* pasted item or part of it falls to R[0] */ 594 if (tb->item_pos == n - tb->rnum[0] && tb->rbytes != -1) { /* we must shift the part of the appended item */ 595 if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) { /* we append to directory item */ 596 int entry_count; 597 598 RFALSE(tb->zeroes_num, 599 "PAP-12145: invalid parameter in case of a directory"); 600 entry_count = ih_entry_count(item_head 601 (tbS0, tb->item_pos)); 602 if (entry_count - tb->rbytes < 603 tb->pos_in_item) 604 /* new directory entry falls into R[0] */ 605 { 606 int paste_entry_position; 607 608 RFALSE(tb->rbytes - 1 >= entry_count || !tb-> insert_size[0], 609 "PAP-12150: no enough of entries to shift to R[0]: rbytes=%d, entry_count=%d", 610 tb->rbytes, entry_count); 611 /* Shift rnum[0]-1 items in whole. Shift rbytes-1 directory entries from directory item number rnum[0] */ 612 leaf_shift_right(tb, tb->rnum[0], tb->rbytes - 1); 613 /* Paste given directory entry to directory item */ 614 paste_entry_position = tb->pos_in_item - entry_count + tb->rbytes - 1; 615 buffer_info_init_right(tb, &bi); 616 leaf_paste_in_buffer(&bi, 0, paste_entry_position, tb->insert_size[0], body, tb->zeroes_num); 617 /* paste entry */ 618 leaf_paste_entries(&bi, 0, paste_entry_position, 1, 619 (struct reiserfs_de_head *) body, 620 body + DEH_SIZE, tb->insert_size[0]); 621 622 if (paste_entry_position == 0) { 623 /* change delimiting keys */ 624 replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0],0); 625 } 626 627 tb->insert_size[0] = 0; 628 tb->pos_in_item++; 629 } else { /* new directory entry doesn't fall into R[0] */ 630 631 leaf_shift_right(tb, tb->rnum[0], tb->rbytes); 632 } 633 } else { /* regular object */ 634 635 int n_shift, n_rem, r_zeroes_number; 636 const char *r_body; 637 638 /* Calculate number of bytes which must be shifted from appended item */ 639 if ((n_shift = tb->rbytes - tb->insert_size[0]) < 0) 640 n_shift = 0; 641 642 RFALSE(tb->pos_in_item != ih_item_len 643 (item_head(tbS0, tb->item_pos)), 644 "PAP-12155: invalid position to paste. ih_item_len=%d, pos_in_item=%d", 645 tb->pos_in_item, ih_item_len 646 (item_head(tbS0, tb->item_pos))); 647 648 leaf_shift_right(tb, tb->rnum[0], n_shift); 649 /* Calculate number of bytes which must remain in body after appending to R[0] */ 650 if ((n_rem = tb->insert_size[0] - tb->rbytes) < 0) 651 n_rem = 0; 652 653 { 654 int version; 655 unsigned long temp_rem = n_rem; 656 657 version = ih_version(item_head(tb->R[0], 0)); 658 if (is_indirect_le_key(version, leaf_key(tb->R[0], 0))) { 659 temp_rem = n_rem << (tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT); 660 } 661 set_le_key_k_offset(version, leaf_key(tb->R[0], 0), 662 le_key_k_offset(version, leaf_key(tb->R[0], 0)) + temp_rem); 663 set_le_key_k_offset(version, internal_key(tb->CFR[0], tb->rkey[0]), 664 le_key_k_offset(version, internal_key(tb->CFR[0], tb->rkey[0])) + temp_rem); 665 } 666/* k_offset (leaf_key(tb->R[0],0)) += n_rem; 667 k_offset (internal_key(tb->CFR[0],tb->rkey[0])) += n_rem;*/ 668 do_balance_mark_internal_dirty(tb, tb->CFR[0], 0); 669 670 /* Append part of body into R[0] */ 671 buffer_info_init_right(tb, &bi); 672 if (n_rem > tb->zeroes_num) { 673 r_zeroes_number = 0; 674 r_body = body + n_rem - tb->zeroes_num; 675 } else { 676 r_body = body; 677 r_zeroes_number = tb->zeroes_num - n_rem; 678 tb->zeroes_num -= r_zeroes_number; 679 } 680 681 leaf_paste_in_buffer(&bi, 0, n_shift, 682 tb->insert_size[0] - n_rem, 683 r_body, r_zeroes_number); 684 685 if (is_indirect_le_ih(item_head(tb->R[0], 0))) { 686#if 0 687 RFALSE(n_rem, 688 "PAP-12160: paste more than one unformatted node pointer"); 689#endif 690 set_ih_free_space(item_head(tb->R[0], 0), 0); 691 } 692 tb->insert_size[0] = n_rem; 693 if (!n_rem) 694 tb->pos_in_item++; 695 } 696 } else { /* pasted item in whole falls into R[0] */ 697 698 struct item_head *pasted; 699 700 ret_val = leaf_shift_right(tb, tb->rnum[0], tb->rbytes); 701 /* append item in R[0] */ 702 if (tb->pos_in_item >= 0) { 703 buffer_info_init_right(tb, &bi); 704 leaf_paste_in_buffer(&bi, tb->item_pos - n + tb->rnum[0], tb->pos_in_item, 705 tb->insert_size[0], body, tb->zeroes_num); 706 } 707 708 /* paste new entry, if item is directory item */ 709 pasted = item_head(tb->R[0], tb->item_pos - n + tb->rnum[0]); 710 if (is_direntry_le_ih(pasted) && tb->pos_in_item >= 0) { 711 leaf_paste_entries(&bi, tb->item_pos - n + tb->rnum[0], 712 tb->pos_in_item, 1, 713 (struct reiserfs_de_head *) body, 714 body + DEH_SIZE, tb->insert_size[0]); 715 if (!tb->pos_in_item) { 716 717 RFALSE(tb->item_pos - n + tb->rnum[0], 718 "PAP-12165: directory item must be first item of node when pasting is in 0th position"); 719 720 /* update delimiting keys */ 721 replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0); 722 } 723 } 724 725 if (is_indirect_le_ih(pasted)) 726 set_ih_free_space(pasted, 0); 727 tb->zeroes_num = tb->insert_size[0] = 0; 728 } 729 } else { /* new item doesn't fall into R[0] */ 730 731 leaf_shift_right(tb, tb->rnum[0], tb->rbytes); 732 } 733 734} 735 736static void balance_leaf_new_nodes_insert(struct tree_balance *tb, 737 struct item_head *ih, 738 const char *body, 739 struct item_head *insert_key, 740 struct buffer_head **insert_ptr, 741 int i) 742{ 743 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 744 int n = B_NR_ITEMS(tbS0); 745 struct buffer_info bi; 746 if (n - tb->snum[i] < tb->item_pos) { /* new item or it's part falls to first new node S_new[i] */ 747 if (tb->item_pos == n - tb->snum[i] + 1 && tb->sbytes[i] != -1) { /* part of new item falls into S_new[i] */ 748 int old_key_comp, old_len, r_zeroes_number; 749 const char *r_body; 750 int version; 751 752 /* Move snum[i]-1 items from S[0] to S_new[i] */ 753 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, 754 tb->snum[i] - 1, -1, 755 tb->S_new[i]); 756 /* Remember key component and item length */ 757 version = ih_version(ih); 758 old_key_comp = le_ih_k_offset(ih); 759 old_len = ih_item_len(ih); 760 761 /* Calculate key component and item length to insert into S_new[i] */ 762 set_le_ih_k_offset(ih, le_ih_k_offset(ih) + 763 ((old_len - tb->sbytes[i]) << (is_indirect_le_ih(ih) ? tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT : 0))); 764 765 put_ih_item_len(ih, tb->sbytes[i]); 766 767 /* Insert part of the item into S_new[i] before 0-th item */ 768 buffer_info_init_bh(tb, &bi, tb->S_new[i]); 769 770 if ((old_len - tb->sbytes[i]) > tb->zeroes_num) { 771 r_zeroes_number = 0; 772 r_body = body + (old_len - tb->sbytes[i]) - tb->zeroes_num; 773 } else { 774 r_body = body; 775 r_zeroes_number = tb->zeroes_num - (old_len - tb->sbytes[i]); 776 tb->zeroes_num -= r_zeroes_number; 777 } 778 779 leaf_insert_into_buf(&bi, 0, ih, r_body, r_zeroes_number); 780 781 /* Calculate key component and item length to insert into S[i] */ 782 set_le_ih_k_offset(ih, old_key_comp); 783 put_ih_item_len(ih, old_len - tb->sbytes[i]); 784 tb->insert_size[0] -= tb->sbytes[i]; 785 } else { /* whole new item falls into S_new[i] */ 786 787 /* Shift snum[0] - 1 items to S_new[i] (sbytes[i] of split item) */ 788 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, 789 tb->snum[i] - 1, tb->sbytes[i], tb->S_new[i]); 790 791 /* Insert new item into S_new[i] */ 792 buffer_info_init_bh(tb, &bi, tb->S_new[i]); 793 leaf_insert_into_buf(&bi, tb->item_pos - n + tb->snum[i] - 1, 794 ih, body, tb->zeroes_num); 795 796 tb->zeroes_num = tb->insert_size[0] = 0; 797 } 798 } 799 800 else { /* new item or it part don't falls into S_new[i] */ 801 802 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, 803 tb->snum[i], tb->sbytes[i], tb->S_new[i]); 804 } 805} 806 807static void balance_leaf_new_nodes_paste(struct tree_balance *tb, 808 struct item_head *ih, 809 const char *body, 810 struct item_head *insert_key, 811 struct buffer_head **insert_ptr, 812 int i) 813{ 814 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 815 int n = B_NR_ITEMS(tbS0); 816 struct buffer_info bi; 817 if (n - tb->snum[i] <= tb->item_pos) { /* pasted item or part if it falls to S_new[i] */ 818 if (tb->item_pos == n - tb->snum[i] && tb->sbytes[i] != -1) { /* we must shift part of the appended item */ 819 struct item_head *aux_ih; 820 821 RFALSE(ih, "PAP-12210: ih must be 0"); 822 823 aux_ih = item_head(tbS0, tb->item_pos); 824 if (is_direntry_le_ih(aux_ih)) { 825 /* we append to directory item */ 826 827 int entry_count; 828 829 entry_count = ih_entry_count(aux_ih); 830 831 if (entry_count - tb->sbytes[i] < tb->pos_in_item && tb->pos_in_item <= entry_count) { 832 /* new directory entry falls into S_new[i] */ 833 834 RFALSE(!tb->insert_size[0], "PAP-12215: insert_size is already 0"); 835 RFALSE(tb->sbytes[i] - 1 >= entry_count, 836 "PAP-12220: there are no so much entries (%d), only %d", 837 tb->sbytes[i] - 1, entry_count); 838 839 /* Shift snum[i]-1 items in whole. Shift sbytes[i] directory entries from directory item number snum[i] */ 840 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], tb->sbytes[i] - 1, tb->S_new[i]); 841 /* Paste given directory entry to directory item */ 842 buffer_info_init_bh(tb, &bi, tb->S_new[i]); 843 leaf_paste_in_buffer(&bi, 0, tb->pos_in_item - entry_count + tb->sbytes[i] - 1, 844 tb->insert_size[0], body, tb->zeroes_num); 845 /* paste new directory entry */ 846 leaf_paste_entries(&bi, 0, tb->pos_in_item - entry_count + tb->sbytes[i] - 1, 1, 847 (struct reiserfs_de_head *) body, 848 body + DEH_SIZE, tb->insert_size[0]); 849 tb->insert_size[0] = 0; 850 tb->pos_in_item++; 851 } else { /* new directory entry doesn't fall into S_new[i] */ 852 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], tb->sbytes[i], tb->S_new[i]); 853 } 854 } else { /* regular object */ 855 856 int n_shift, n_rem, r_zeroes_number; 857 const char *r_body; 858 859 RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)) || tb->insert_size[0] <= 0, 860 "PAP-12225: item too short or insert_size <= 0"); 861 862 /* Calculate number of bytes which must be shifted from appended item */ 863 n_shift = tb->sbytes[i] - tb->insert_size[0]; 864 if (n_shift < 0) 865 n_shift = 0; 866 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], n_shift, tb->S_new[i]); 867 868 /* Calculate number of bytes which must remain in body after append to S_new[i] */ 869 n_rem = tb->insert_size[0] - tb->sbytes[i]; 870 if (n_rem < 0) 871 n_rem = 0; 872 /* Append part of body into S_new[0] */ 873 buffer_info_init_bh(tb, &bi, tb->S_new[i]); 874 if (n_rem > tb->zeroes_num) { 875 r_zeroes_number = 0; 876 r_body = body + n_rem - tb->zeroes_num; 877 } else { 878 r_body = body; 879 r_zeroes_number = tb->zeroes_num - n_rem; 880 tb->zeroes_num -= r_zeroes_number; 881 } 882 883 leaf_paste_in_buffer(&bi, 0, n_shift, 884 tb->insert_size[0] - n_rem, 885 r_body, r_zeroes_number); 886 { 887 struct item_head *tmp; 888 889 tmp = item_head(tb->S_new[i], 0); 890 if (is_indirect_le_ih 891 (tmp)) { 892 set_ih_free_space(tmp, 0); 893 set_le_ih_k_offset(tmp, le_ih_k_offset(tmp) + (n_rem << (tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT))); 894 } else { 895 set_le_ih_k_offset(tmp, le_ih_k_offset(tmp) + n_rem); 896 } 897 } 898 899 tb->insert_size[0] = n_rem; 900 if (!n_rem) 901 tb->pos_in_item++; 902 } 903 } else 904 /* item falls wholly into S_new[i] */ 905 { 906 int leaf_mi; 907 struct item_head *pasted; 908 909#ifdef CONFIG_REISERFS_CHECK 910 struct item_head *ih_check = item_head(tbS0, tb->item_pos); 911 912 if (!is_direntry_le_ih(ih_check) 913 && (tb->pos_in_item != ih_item_len(ih_check) 914 || tb->insert_size[0] <= 0)) 915 reiserfs_panic(tb->tb_sb, 916 "PAP-12235", 917 "pos_in_item " 918 "must be equal " 919 "to ih_item_len"); 920#endif /* CONFIG_REISERFS_CHECK */ 921 922 leaf_mi = leaf_move_items(LEAF_FROM_S_TO_SNEW, 923 tb, tb->snum[i], 924 tb->sbytes[i], 925 tb->S_new[i]); 926 927 RFALSE(leaf_mi, 928 "PAP-12240: unexpected value returned by leaf_move_items (%d)", 929 leaf_mi); 930 931 /* paste into item */ 932 buffer_info_init_bh(tb, &bi, tb->S_new[i]); 933 leaf_paste_in_buffer(&bi, 934 tb->item_pos - n + tb->snum[i], 935 tb->pos_in_item, 936 tb->insert_size[0], 937 body, tb->zeroes_num); 938 939 pasted = item_head(tb->S_new[i], tb->item_pos - n + tb->snum[i]); 940 if (is_direntry_le_ih(pasted)) { 941 leaf_paste_entries(&bi, 942 tb->item_pos - n + tb->snum[i], 943 tb->pos_in_item, 1, 944 (struct reiserfs_de_head *)body, 945 body + DEH_SIZE, 946 tb->insert_size[0] 947 ); 948 } 949 950 /* if we paste to indirect item update ih_free_space */ 951 if (is_indirect_le_ih(pasted)) 952 set_ih_free_space(pasted, 0); 953 tb->zeroes_num = tb->insert_size[0] = 0; 954 } 955 } 956 957 else { /* pasted item doesn't fall into S_new[i] */ 958 959 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, 960 tb->snum[i], tb->sbytes[i], tb->S_new[i]); 961 } 962 963} 964 965static void balance_leaf_finish_node_insert(struct tree_balance *tb, 966 struct item_head *ih, 967 const char *body) 968{ 969 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 970 struct buffer_info bi; 971 buffer_info_init_tbS0(tb, &bi); 972 leaf_insert_into_buf(&bi, tb->item_pos, ih, 973 body, tb->zeroes_num); 974 975 /* 976 * If we insert the first key 977 * change the delimiting key 978 */ 979 if (tb->item_pos == 0) { 980 if (tb->CFL[0]) /* can be 0 in reiserfsck */ 981 replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0); 982 } 983} 984 985static void balance_leaf_finish_node_paste(struct tree_balance *tb, 986 struct item_head *ih, 987 const char *body) 988{ 989 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 990 struct buffer_info bi; 991 struct item_head *pasted; 992 993 pasted = item_head(tbS0, tb->item_pos); 994 /* when directory, may be new entry already pasted */ 995 if (is_direntry_le_ih(pasted)) { 996 if (tb->pos_in_item >= 0 && tb->pos_in_item <= ih_entry_count(pasted)) { 997 998 RFALSE(!tb->insert_size[0], 999 "PAP-12260: insert_size is 0 already"); 1000 1001 /* prepare space */ 1002 buffer_info_init_tbS0(tb, &bi); 1003 leaf_paste_in_buffer(&bi, tb->item_pos, tb->pos_in_item, 1004 tb->insert_size[0], body, 1005 tb->zeroes_num); 1006 1007 /* paste entry */ 1008 leaf_paste_entries(&bi, tb->item_pos, tb->pos_in_item, 1, 1009 (struct reiserfs_de_head *)body, 1010 body + DEH_SIZE, 1011 tb->insert_size[0]); 1012 if (!tb->item_pos && !tb->pos_in_item) { 1013 RFALSE(!tb->CFL[0] || !tb->L[0], 1014 "PAP-12270: CFL[0]/L[0] must be specified"); 1015 if (tb->CFL[0]) 1016 replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0); 1017 } 1018 tb->insert_size[0] = 0; 1019 } 1020 } else { /* regular object */ 1021 if (tb->pos_in_item == ih_item_len(pasted)) { 1022 1023 RFALSE(tb->insert_size[0] <= 0, 1024 "PAP-12275: insert size must not be %d", 1025 tb->insert_size[0]); 1026 buffer_info_init_tbS0(tb, &bi); 1027 leaf_paste_in_buffer(&bi, tb->item_pos, tb->pos_in_item, 1028 tb->insert_size[0], body, tb->zeroes_num); 1029 1030 if (is_indirect_le_ih(pasted)) { 1031#if 0 1032 RFALSE(tb-> 1033 insert_size[0] != 1034 UNFM_P_SIZE, 1035 "PAP-12280: insert_size for indirect item must be %d, not %d", 1036 UNFM_P_SIZE, 1037 tb-> 1038 insert_size[0]); 1039#endif 1040 set_ih_free_space(pasted, 0); 1041 } 1042 tb->insert_size[0] = 0; 1043 } 1044#ifdef CONFIG_REISERFS_CHECK 1045 else { 1046 if (tb->insert_size[0]) { 1047 print_cur_tb("12285"); 1048 reiserfs_panic(tb->tb_sb, 1049 "PAP-12285", 1050 "insert_size " 1051 "must be 0 " 1052 "(%d)", 1053 tb->insert_size[0]); 1054 } 1055 } 1056#endif /* CONFIG_REISERFS_CHECK */ 1057 1058 } 1059} 1060 1061/** 1062 * balance_leaf - reiserfs tree balancing algorithm 1063 * @tb: tree balance state 1064 * @ih: item header of inserted item (little endian) 1065 * @body: body of inserted item or bytes to paste 1066 * @flag: i - insert, d - delete, c - cut, p - paste (see do_balance) 1067 * passed back: 1068 * @insert_key: key to insert new nodes 1069 * @insert_ptr: array of nodes to insert at the next level 1070 * 1071 * In our processing of one level we sometimes determine what must be 1072 * inserted into the next higher level. This insertion consists of a 1073 * key or two keys and their corresponding pointers. 1074 */ 1075static int balance_leaf(struct tree_balance *tb, struct item_head *ih, 1076 const char *body, int flag, 1077 struct item_head *insert_key, 1078 struct buffer_head **insert_ptr) 1079{ 1080 struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); 1081 int n, i; 1082 1083 PROC_INFO_INC(tb->tb_sb, balance_at[0]); 1084 1085 /* Make balance in case insert_size[0] < 0 */ 1086 if (tb->insert_size[0] < 0) 1087 return balance_leaf_when_delete(tb, flag); 1088 1089 tb->item_pos = PATH_LAST_POSITION(tb->tb_path), 1090 tb->pos_in_item = tb->tb_path->pos_in_item, 1091 tb->zeroes_num = 0; 1092 if (flag == M_INSERT && !body) 1093 tb->zeroes_num = ih_item_len(ih); 1094 1095 /* 1096 * for indirect item pos_in_item is measured in unformatted node 1097 * pointers. Recalculate to bytes 1098 */ 1099 if (flag != M_INSERT 1100 && is_indirect_le_ih(item_head(tbS0, tb->item_pos))) 1101 tb->pos_in_item *= UNFM_P_SIZE; 1102 1103 if (tb->lnum[0] > 0) { 1104 /* Shift lnum[0] items from S[0] to the left neighbor L[0] */ 1105 if (tb->item_pos < tb->lnum[0]) { 1106 /* new item or it part falls to L[0], shift it too */ 1107 n = B_NR_ITEMS(tb->L[0]); 1108 1109 switch (flag) { 1110 case M_INSERT: /* insert item into L[0] */ 1111 balance_leaf_insert_left(tb, ih, body); 1112 break; 1113 1114 case M_PASTE: /* append item in L[0] */ 1115 balance_leaf_paste_left(tb, ih, body); 1116 break; 1117 default: /* cases d and t */ 1118 reiserfs_panic(tb->tb_sb, "PAP-12130", 1119 "lnum > 0: unexpected mode: " 1120 " %s(%d)", 1121 (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag); 1122 } 1123 } else { 1124 /* new item doesn't fall into L[0] */ 1125 leaf_shift_left(tb, tb->lnum[0], tb->lbytes); 1126 } 1127 } 1128 1129 /* tb->lnum[0] > 0 */ 1130 /* Calculate new item position */ 1131 tb->item_pos -= (tb->lnum[0] - ((tb->lbytes != -1) ? 1 : 0)); 1132 1133 if (tb->rnum[0] > 0) { 1134 /* shift rnum[0] items from S[0] to the right neighbor R[0] */ 1135 n = B_NR_ITEMS(tbS0); 1136 switch (flag) { 1137 1138 case M_INSERT: /* insert item */ 1139 balance_leaf_insert_right(tb, ih, body); 1140 break; 1141 1142 case M_PASTE: /* append item */ 1143 balance_leaf_paste_right(tb, ih, body); 1144 break; 1145 default: /* cases d and t */ 1146 reiserfs_panic(tb->tb_sb, "PAP-12175", 1147 "rnum > 0: unexpected mode: %s(%d)", 1148 (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag); 1149 } 1150 1151 } 1152 1153 /* tb->rnum[0] > 0 */ 1154 RFALSE(tb->blknum[0] > 3, 1155 "PAP-12180: blknum can not be %d. It must be <= 3", tb->blknum[0]); 1156 RFALSE(tb->blknum[0] < 0, 1157 "PAP-12185: blknum can not be %d. It must be >= 0", tb->blknum[0]); 1158 1159 /* 1160 * if while adding to a node we discover that it is possible to split 1161 * it in two, and merge the left part into the left neighbor and the 1162 * right part into the right neighbor, eliminating the node 1163 */ 1164 if (tb->blknum[0] == 0) { /* node S[0] is empty now */ 1165 1166 RFALSE(!tb->lnum[0] || !tb->rnum[0], 1167 "PAP-12190: lnum and rnum must not be zero"); 1168 /* 1169 * if insertion was done before 0-th position in R[0], right 1170 * delimiting key of the tb->L[0]'s and left delimiting key are 1171 * not set correctly 1172 */ 1173 if (tb->CFL[0]) { 1174 if (!tb->CFR[0]) 1175 reiserfs_panic(tb->tb_sb, "vs-12195", 1176 "CFR not initialized"); 1177 copy_key(internal_key(tb->CFL[0], tb->lkey[0]), 1178 internal_key(tb->CFR[0], tb->rkey[0])); 1179 do_balance_mark_internal_dirty(tb, tb->CFL[0], 0); 1180 } 1181 1182 reiserfs_invalidate_buffer(tb, tbS0); 1183 return 0; 1184 } 1185 1186 /* Fill new nodes that appear in place of S[0] */ 1187 for (i = tb->blknum[0] - 2; i >= 0; i--) { 1188 1189 RFALSE(!tb->snum[i], 1190 "PAP-12200: snum[%d] == %d. Must be > 0", i, 1191 tb->snum[i]); 1192 1193 /* here we shift from S to S_new nodes */ 1194 1195 tb->S_new[i] = get_FEB(tb); 1196 1197 /* initialized block type and tree level */ 1198 set_blkh_level(B_BLK_HEAD(tb->S_new[i]), DISK_LEAF_NODE_LEVEL); 1199 1200 n = B_NR_ITEMS(tbS0); 1201 1202 switch (flag) { 1203 case M_INSERT: /* insert item */ 1204 balance_leaf_new_nodes_insert(tb, ih, body, insert_key, 1205 insert_ptr, i); 1206 break; 1207 1208 case M_PASTE: /* append item */ 1209 balance_leaf_new_nodes_paste(tb, ih, body, insert_key, 1210 insert_ptr, i); 1211 break; 1212 default: /* cases d and t */ 1213 reiserfs_panic(tb->tb_sb, "PAP-12245", 1214 "blknum > 2: unexpected mode: %s(%d)", 1215 (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag); 1216 } 1217 1218 memcpy(insert_key + i, leaf_key(tb->S_new[i], 0), KEY_SIZE); 1219 insert_ptr[i] = tb->S_new[i]; 1220 1221 RFALSE(!buffer_journaled(tb->S_new[i]) 1222 || buffer_journal_dirty(tb->S_new[i]) 1223 || buffer_dirty(tb->S_new[i]), 1224 "PAP-12247: S_new[%d] : (%b)", 1225 i, tb->S_new[i]); 1226 } 1227 1228 /* if the affected item was not wholly shifted then we perform all necessary operations on that part or whole of the 1229 affected item which remains in S */ 1230 if (0 <= tb->item_pos && tb->item_pos < tb->s0num) { /* if we must insert or append into buffer S[0] */ 1231 1232 switch (flag) { 1233 case M_INSERT: /* insert item into S[0] */ 1234 balance_leaf_finish_node_insert(tb, ih, body); 1235 break; 1236 1237 case M_PASTE: /* append item in S[0] */ 1238 balance_leaf_finish_node_paste(tb, ih, body); 1239 break; 1240 } 1241 } 1242#ifdef CONFIG_REISERFS_CHECK 1243 if (flag == M_PASTE && tb->insert_size[0]) { 1244 print_cur_tb("12290"); 1245 reiserfs_panic(tb->tb_sb, 1246 "PAP-12290", "insert_size is still not 0 (%d)", 1247 tb->insert_size[0]); 1248 } 1249#endif 1250 1251 /* Leaf level of the tree is balanced (end of balance_leaf) */ 1252 return 0; 1253} 1254 1255/* Make empty node */ 1256void make_empty_node(struct buffer_info *bi) 1257{ 1258 struct block_head *blkh; 1259 1260 RFALSE(bi->bi_bh == NULL, "PAP-12295: pointer to the buffer is NULL"); 1261 1262 blkh = B_BLK_HEAD(bi->bi_bh); 1263 set_blkh_nr_item(blkh, 0); 1264 set_blkh_free_space(blkh, MAX_CHILD_SIZE(bi->bi_bh)); 1265 1266 if (bi->bi_parent) 1267 B_N_CHILD(bi->bi_parent, bi->bi_position)->dc_size = 0; /* Endian safe if 0 */ 1268} 1269 1270/* Get first empty buffer */ 1271struct buffer_head *get_FEB(struct tree_balance *tb) 1272{ 1273 int i; 1274 struct buffer_info bi; 1275 1276 for (i = 0; i < MAX_FEB_SIZE; i++) 1277 if (tb->FEB[i] != NULL) 1278 break; 1279 1280 if (i == MAX_FEB_SIZE) 1281 reiserfs_panic(tb->tb_sb, "vs-12300", "FEB list is empty"); 1282 1283 buffer_info_init_bh(tb, &bi, tb->FEB[i]); 1284 make_empty_node(&bi); 1285 set_buffer_uptodate(tb->FEB[i]); 1286 tb->used[i] = tb->FEB[i]; 1287 tb->FEB[i] = NULL; 1288 1289 return tb->used[i]; 1290} 1291 1292/* This is now used because reiserfs_free_block has to be able to schedule. */ 1293static void store_thrown(struct tree_balance *tb, struct buffer_head *bh) 1294{ 1295 int i; 1296 1297 if (buffer_dirty(bh)) 1298 reiserfs_warning(tb->tb_sb, "reiserfs-12320", 1299 "called with dirty buffer"); 1300 for (i = 0; i < ARRAY_SIZE(tb->thrown); i++) 1301 if (!tb->thrown[i]) { 1302 tb->thrown[i] = bh; 1303 get_bh(bh); /* free_thrown puts this */ 1304 return; 1305 } 1306 reiserfs_warning(tb->tb_sb, "reiserfs-12321", 1307 "too many thrown buffers"); 1308} 1309 1310static void free_thrown(struct tree_balance *tb) 1311{ 1312 int i; 1313 b_blocknr_t blocknr; 1314 for (i = 0; i < ARRAY_SIZE(tb->thrown); i++) { 1315 if (tb->thrown[i]) { 1316 blocknr = tb->thrown[i]->b_blocknr; 1317 if (buffer_dirty(tb->thrown[i])) 1318 reiserfs_warning(tb->tb_sb, "reiserfs-12322", 1319 "called with dirty buffer %d", 1320 blocknr); 1321 brelse(tb->thrown[i]); /* incremented in store_thrown */ 1322 reiserfs_free_block(tb->transaction_handle, NULL, 1323 blocknr, 0); 1324 } 1325 } 1326} 1327 1328void reiserfs_invalidate_buffer(struct tree_balance *tb, struct buffer_head *bh) 1329{ 1330 struct block_head *blkh; 1331 blkh = B_BLK_HEAD(bh); 1332 set_blkh_level(blkh, FREE_LEVEL); 1333 set_blkh_nr_item(blkh, 0); 1334 1335 clear_buffer_dirty(bh); 1336 store_thrown(tb, bh); 1337} 1338 1339/* Replace n_dest'th key in buffer dest by n_src'th key of buffer src.*/ 1340void replace_key(struct tree_balance *tb, struct buffer_head *dest, int n_dest, 1341 struct buffer_head *src, int n_src) 1342{ 1343 1344 RFALSE(dest == NULL || src == NULL, 1345 "vs-12305: source or destination buffer is 0 (src=%p, dest=%p)", 1346 src, dest); 1347 RFALSE(!B_IS_KEYS_LEVEL(dest), 1348 "vs-12310: invalid level (%z) for destination buffer. dest must be leaf", 1349 dest); 1350 RFALSE(n_dest < 0 || n_src < 0, 1351 "vs-12315: src(%d) or dest(%d) key number < 0", n_src, n_dest); 1352 RFALSE(n_dest >= B_NR_ITEMS(dest) || n_src >= B_NR_ITEMS(src), 1353 "vs-12320: src(%d(%d)) or dest(%d(%d)) key number is too big", 1354 n_src, B_NR_ITEMS(src), n_dest, B_NR_ITEMS(dest)); 1355 1356 if (B_IS_ITEMS_LEVEL(src)) 1357 /* source buffer contains leaf node */ 1358 memcpy(internal_key(dest, n_dest), item_head(src, n_src), 1359 KEY_SIZE); 1360 else 1361 memcpy(internal_key(dest, n_dest), internal_key(src, n_src), 1362 KEY_SIZE); 1363 1364 do_balance_mark_internal_dirty(tb, dest, 0); 1365} 1366 1367int get_left_neighbor_position(struct tree_balance *tb, int h) 1368{ 1369 int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1); 1370 1371 RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FL[h] == NULL, 1372 "vs-12325: FL[%d](%p) or F[%d](%p) does not exist", 1373 h, tb->FL[h], h, PATH_H_PPARENT(tb->tb_path, h)); 1374 1375 if (Sh_position == 0) 1376 return B_NR_ITEMS(tb->FL[h]); 1377 else 1378 return Sh_position - 1; 1379} 1380 1381int get_right_neighbor_position(struct tree_balance *tb, int h) 1382{ 1383 int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1); 1384 1385 RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FR[h] == NULL, 1386 "vs-12330: F[%d](%p) or FR[%d](%p) does not exist", 1387 h, PATH_H_PPARENT(tb->tb_path, h), h, tb->FR[h]); 1388 1389 if (Sh_position == B_NR_ITEMS(PATH_H_PPARENT(tb->tb_path, h))) 1390 return 0; 1391 else 1392 return Sh_position + 1; 1393} 1394 1395#ifdef CONFIG_REISERFS_CHECK 1396 1397int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value); 1398static void check_internal_node(struct super_block *s, struct buffer_head *bh, 1399 char *mes) 1400{ 1401 struct disk_child *dc; 1402 int i; 1403 1404 RFALSE(!bh, "PAP-12336: bh == 0"); 1405 1406 if (!bh || !B_IS_IN_TREE(bh)) 1407 return; 1408 1409 RFALSE(!buffer_dirty(bh) && 1410 !(buffer_journaled(bh) || buffer_journal_dirty(bh)), 1411 "PAP-12337: buffer (%b) must be dirty", bh); 1412 dc = B_N_CHILD(bh, 0); 1413 1414 for (i = 0; i <= B_NR_ITEMS(bh); i++, dc++) { 1415 if (!is_reusable(s, dc_block_number(dc), 1)) { 1416 print_cur_tb(mes); 1417 reiserfs_panic(s, "PAP-12338", 1418 "invalid child pointer %y in %b", 1419 dc, bh); 1420 } 1421 } 1422} 1423 1424static int locked_or_not_in_tree(struct tree_balance *tb, 1425 struct buffer_head *bh, char *which) 1426{ 1427 if ((!buffer_journal_prepared(bh) && buffer_locked(bh)) || 1428 !B_IS_IN_TREE(bh)) { 1429 reiserfs_warning(tb->tb_sb, "vs-12339", "%s (%b)", which, bh); 1430 return 1; 1431 } 1432 return 0; 1433} 1434 1435static int check_before_balancing(struct tree_balance *tb) 1436{ 1437 int retval = 0; 1438 1439 if (REISERFS_SB(tb->tb_sb)->cur_tb) { 1440 reiserfs_panic(tb->tb_sb, "vs-12335", "suspect that schedule " 1441 "occurred based on cur_tb not being null at " 1442 "this point in code. do_balance cannot properly " 1443 "handle concurrent tree accesses on a same " 1444 "mount point."); 1445 } 1446 1447 /* 1448 * double check that buffers that we will modify are unlocked. 1449 * (fix_nodes should already have prepped all of these for us). 1450 */ 1451 if (tb->lnum[0]) { 1452 retval |= locked_or_not_in_tree(tb, tb->L[0], "L[0]"); 1453 retval |= locked_or_not_in_tree(tb, tb->FL[0], "FL[0]"); 1454 retval |= locked_or_not_in_tree(tb, tb->CFL[0], "CFL[0]"); 1455 check_leaf(tb->L[0]); 1456 } 1457 if (tb->rnum[0]) { 1458 retval |= locked_or_not_in_tree(tb, tb->R[0], "R[0]"); 1459 retval |= locked_or_not_in_tree(tb, tb->FR[0], "FR[0]"); 1460 retval |= locked_or_not_in_tree(tb, tb->CFR[0], "CFR[0]"); 1461 check_leaf(tb->R[0]); 1462 } 1463 retval |= locked_or_not_in_tree(tb, PATH_PLAST_BUFFER(tb->tb_path), 1464 "S[0]"); 1465 check_leaf(PATH_PLAST_BUFFER(tb->tb_path)); 1466 1467 return retval; 1468} 1469 1470static void check_after_balance_leaf(struct tree_balance *tb) 1471{ 1472 if (tb->lnum[0]) { 1473 if (B_FREE_SPACE(tb->L[0]) != 1474 MAX_CHILD_SIZE(tb->L[0]) - 1475 dc_size(B_N_CHILD 1476 (tb->FL[0], get_left_neighbor_position(tb, 0)))) { 1477 print_cur_tb("12221"); 1478 reiserfs_panic(tb->tb_sb, "PAP-12355", 1479 "shift to left was incorrect"); 1480 } 1481 } 1482 if (tb->rnum[0]) { 1483 if (B_FREE_SPACE(tb->R[0]) != 1484 MAX_CHILD_SIZE(tb->R[0]) - 1485 dc_size(B_N_CHILD 1486 (tb->FR[0], get_right_neighbor_position(tb, 0)))) { 1487 print_cur_tb("12222"); 1488 reiserfs_panic(tb->tb_sb, "PAP-12360", 1489 "shift to right was incorrect"); 1490 } 1491 } 1492 if (PATH_H_PBUFFER(tb->tb_path, 1) && 1493 (B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0)) != 1494 (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) - 1495 dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1), 1496 PATH_H_POSITION(tb->tb_path, 1)))))) { 1497 int left = B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0)); 1498 int right = (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) - 1499 dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1), 1500 PATH_H_POSITION(tb->tb_path, 1501 1)))); 1502 print_cur_tb("12223"); 1503 reiserfs_warning(tb->tb_sb, "reiserfs-12363", 1504 "B_FREE_SPACE (PATH_H_PBUFFER(tb->tb_path,0)) = %d; " 1505 "MAX_CHILD_SIZE (%d) - dc_size( %y, %d ) [%d] = %d", 1506 left, 1507 MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)), 1508 PATH_H_PBUFFER(tb->tb_path, 1), 1509 PATH_H_POSITION(tb->tb_path, 1), 1510 dc_size(B_N_CHILD 1511 (PATH_H_PBUFFER(tb->tb_path, 1), 1512 PATH_H_POSITION(tb->tb_path, 1))), 1513 right); 1514 reiserfs_panic(tb->tb_sb, "PAP-12365", "S is incorrect"); 1515 } 1516} 1517 1518static void check_leaf_level(struct tree_balance *tb) 1519{ 1520 check_leaf(tb->L[0]); 1521 check_leaf(tb->R[0]); 1522 check_leaf(PATH_PLAST_BUFFER(tb->tb_path)); 1523} 1524 1525static void check_internal_levels(struct tree_balance *tb) 1526{ 1527 int h; 1528 1529 /* check all internal nodes */ 1530 for (h = 1; tb->insert_size[h]; h++) { 1531 check_internal_node(tb->tb_sb, PATH_H_PBUFFER(tb->tb_path, h), 1532 "BAD BUFFER ON PATH"); 1533 if (tb->lnum[h]) 1534 check_internal_node(tb->tb_sb, tb->L[h], "BAD L"); 1535 if (tb->rnum[h]) 1536 check_internal_node(tb->tb_sb, tb->R[h], "BAD R"); 1537 } 1538 1539} 1540 1541#endif 1542 1543/* 1544 * Now we have all of the buffers that must be used in balancing of 1545 * the tree. We rely on the assumption that schedule() will not occur 1546 * while do_balance works. ( Only interrupt handlers are acceptable.) 1547 * We balance the tree according to the analysis made before this, 1548 * using buffers already obtained. For SMP support it will someday be 1549 * necessary to add ordered locking of tb. 1550 */ 1551 1552/* 1553 * Some interesting rules of balancing: 1554 * we delete a maximum of two nodes per level per balancing: we never 1555 * delete R, when we delete two of three nodes L, S, R then we move 1556 * them into R. 1557 * 1558 * we only delete L if we are deleting two nodes, if we delete only 1559 * one node we delete S 1560 * 1561 * if we shift leaves then we shift as much as we can: this is a 1562 * deliberate policy of extremism in node packing which results in 1563 * higher average utilization after repeated random balance operations 1564 * at the cost of more memory copies and more balancing as a result of 1565 * small insertions to full nodes. 1566 * 1567 * if we shift internal nodes we try to evenly balance the node 1568 * utilization, with consequent less balancing at the cost of lower 1569 * utilization. 1570 * 1571 * one could argue that the policy for directories in leaves should be 1572 * that of internal nodes, but we will wait until another day to 1573 * evaluate this.... It would be nice to someday measure and prove 1574 * these assumptions as to what is optimal.... 1575 */ 1576 1577static inline void do_balance_starts(struct tree_balance *tb) 1578{ 1579 /* use print_cur_tb() to see initial state of struct tree_balance */ 1580 1581 /* store_print_tb (tb); */ 1582 1583 /* do not delete, just comment it out */ 1584 /* 1585 print_tb(flag, PATH_LAST_POSITION(tb->tb_path), 1586 tb->tb_path->pos_in_item, tb, "check"); 1587 */ 1588 RFALSE(check_before_balancing(tb), "PAP-12340: locked buffers in TB"); 1589#ifdef CONFIG_REISERFS_CHECK 1590 REISERFS_SB(tb->tb_sb)->cur_tb = tb; 1591#endif 1592} 1593 1594static inline void do_balance_completed(struct tree_balance *tb) 1595{ 1596 1597#ifdef CONFIG_REISERFS_CHECK 1598 check_leaf_level(tb); 1599 check_internal_levels(tb); 1600 REISERFS_SB(tb->tb_sb)->cur_tb = NULL; 1601#endif 1602 1603 /* 1604 * reiserfs_free_block is no longer schedule safe. So, we need to 1605 * put the buffers we want freed on the thrown list during do_balance, 1606 * and then free them now 1607 */ 1608 1609 REISERFS_SB(tb->tb_sb)->s_do_balance++; 1610 1611 /* release all nodes hold to perform the balancing */ 1612 unfix_nodes(tb); 1613 1614 free_thrown(tb); 1615} 1616 1617/* 1618 * do_balance - balance the tree 1619 * 1620 * @tb: tree_balance structure 1621 * @ih: item header of inserted item 1622 * @body: body of inserted item or bytes to paste 1623 * @flag: 'i' - insert, 'd' - delete, 'c' - cut, 'p' paste 1624 * 1625 * Cut means delete part of an item (includes removing an entry from a 1626 * directory). 1627 * 1628 * Delete means delete whole item. 1629 * 1630 * Insert means add a new item into the tree. 1631 * 1632 * Paste means to append to the end of an existing file or to 1633 * insert a directory entry. 1634 */ 1635void do_balance(struct tree_balance *tb, struct item_head *ih, 1636 const char *body, int flag) 1637{ 1638 int child_pos; /* position of a child node in its parent */ 1639 int h; /* level of the tree being processed */ 1640 1641 /* 1642 * in our processing of one level we sometimes determine what 1643 * must be inserted into the next higher level. This insertion 1644 * consists of a key or two keys and their corresponding 1645 * pointers 1646 */ 1647 struct item_head insert_key[2]; 1648 1649 /* inserted node-ptrs for the next level */ 1650 struct buffer_head *insert_ptr[2]; 1651 1652 tb->tb_mode = flag; 1653 tb->need_balance_dirty = 0; 1654 1655 if (FILESYSTEM_CHANGED_TB(tb)) { 1656 reiserfs_panic(tb->tb_sb, "clm-6000", "fs generation has " 1657 "changed"); 1658 } 1659 /* if we have no real work to do */ 1660 if (!tb->insert_size[0]) { 1661 reiserfs_warning(tb->tb_sb, "PAP-12350", 1662 "insert_size == 0, mode == %c", flag); 1663 unfix_nodes(tb); 1664 return; 1665 } 1666 1667 atomic_inc(&fs_generation(tb->tb_sb)); 1668 do_balance_starts(tb); 1669 1670 /* 1671 * balance_leaf returns 0 except if combining L R and S into 1672 * one node. see balance_internal() for explanation of this 1673 * line of code. 1674 */ 1675 child_pos = PATH_H_B_ITEM_ORDER(tb->tb_path, 0) + 1676 balance_leaf(tb, ih, body, flag, insert_key, insert_ptr); 1677 1678#ifdef CONFIG_REISERFS_CHECK 1679 check_after_balance_leaf(tb); 1680#endif 1681 1682 /* Balance internal level of the tree. */ 1683 for (h = 1; h < MAX_HEIGHT && tb->insert_size[h]; h++) 1684 child_pos = 1685 balance_internal(tb, h, child_pos, insert_key, insert_ptr); 1686 1687 do_balance_completed(tb); 1688 1689} 1690