fs/reiserfs/ibalance.c

   1 /*
   2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
   3  */
   4
   5 #include <linux/uaccess.h>
   6 #include <linux/string.h>
   7 #include <linux/time.h>
   8 #include "reiserfs.h"
   9 #include <linux/buffer_head.h>
  10
  11 /* this is one and only function that is used outside (do_balance.c) */
  12 int balance_internal(struct tree_balance *,
  13                      int, int, struct item_head *, struct buffer_head **);
  14
  15 /*
  16  * modes of internal_shift_left, internal_shift_right and
  17  * internal_insert_childs
  18  */
  19 #define INTERNAL_SHIFT_FROM_S_TO_L 0
  20 #define INTERNAL_SHIFT_FROM_R_TO_S 1
  21 #define INTERNAL_SHIFT_FROM_L_TO_S 2
  22 #define INTERNAL_SHIFT_FROM_S_TO_R 3
  23 #define INTERNAL_INSERT_TO_S 4
  24 #define INTERNAL_INSERT_TO_L 5
  25 #define INTERNAL_INSERT_TO_R 6
  26
  27 static void internal_define_dest_src_infos(int shift_mode,
  28                                            struct tree_balance *tb,
  29                                            int h,
  30                                            struct buffer_info *dest_bi,
  31                                            struct buffer_info *src_bi,
  32                                            int *d_key, struct buffer_head **cf)
  33 {
  34         memset(dest_bi, 0, sizeof(struct buffer_info));
  35         memset(src_bi, 0, sizeof(struct buffer_info));
  36         /* define dest, src, dest parent, dest position */
  37         switch (shift_mode) {
  38
  39         /* used in internal_shift_left */
  40         case INTERNAL_SHIFT_FROM_S_TO_L:
  41                 src_bi->tb = tb;
  42                 src_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
  43                 src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
  44                 src_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
  45                 dest_bi->tb = tb;
  46                 dest_bi->bi_bh = tb->L[h];
  47                 dest_bi->bi_parent = tb->FL[h];
  48                 dest_bi->bi_position = get_left_neighbor_position(tb, h);
  49                 *d_key = tb->lkey[h];
  50                 *cf = tb->CFL[h];
  51                 break;
  52         case INTERNAL_SHIFT_FROM_L_TO_S:
  53                 src_bi->tb = tb;
  54                 src_bi->bi_bh = tb->L[h];
  55                 src_bi->bi_parent = tb->FL[h];
  56                 src_bi->bi_position = get_left_neighbor_position(tb, h);
  57                 dest_bi->tb = tb;
  58                 dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
  59                 dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
  60                 /* dest position is analog of dest->b_item_order */
  61                 dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
  62                 *d_key = tb->lkey[h];
  63                 *cf = tb->CFL[h];
  64                 break;
  65
  66         /* used in internal_shift_left */
  67         case INTERNAL_SHIFT_FROM_R_TO_S:
  68                 src_bi->tb = tb;
  69                 src_bi->bi_bh = tb->R[h];
  70                 src_bi->bi_parent = tb->FR[h];
  71                 src_bi->bi_position = get_right_neighbor_position(tb, h);
  72                 dest_bi->tb = tb;
  73                 dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
  74                 dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
  75                 dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
  76                 *d_key = tb->rkey[h];
  77                 *cf = tb->CFR[h];
  78                 break;
  79
  80         case INTERNAL_SHIFT_FROM_S_TO_R:
  81                 src_bi->tb = tb;
  82                 src_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
  83                 src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
  84                 src_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
  85                 dest_bi->tb = tb;
  86                 dest_bi->bi_bh = tb->R[h];
  87                 dest_bi->bi_parent = tb->FR[h];
  88                 dest_bi->bi_position = get_right_neighbor_position(tb, h);
  89                 *d_key = tb->rkey[h];
  90                 *cf = tb->CFR[h];
  91                 break;
  92
  93         case INTERNAL_INSERT_TO_L:
  94                 dest_bi->tb = tb;
  95                 dest_bi->bi_bh = tb->L[h];
  96                 dest_bi->bi_parent = tb->FL[h];
  97                 dest_bi->bi_position = get_left_neighbor_position(tb, h);
  98                 break;
  99
 100         case INTERNAL_INSERT_TO_S:
 101                 dest_bi->tb = tb;
 102                 dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
 103                 dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
 104                 dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
 105                 break;
 106
 107         case INTERNAL_INSERT_TO_R:
 108                 dest_bi->tb = tb;
 109                 dest_bi->bi_bh = tb->R[h];
 110                 dest_bi->bi_parent = tb->FR[h];
 111                 dest_bi->bi_position = get_right_neighbor_position(tb, h);
 112                 break;
 113
 114         default:
 115                 reiserfs_panic(tb->tb_sb, "ibalance-1",
 116                                "shift type is unknown (%d)",
 117                                shift_mode);
 118         }
 119 }
 120
 121 /*
 122  * Insert count node pointers into buffer cur before position to + 1.
 123  * Insert count items into buffer cur before position to.
 124  * Items and node pointers are specified by inserted and bh respectively.
 125  */
 126 static void internal_insert_childs(struct buffer_info *cur_bi,
 127                                    int to, int count,
 128                                    struct item_head *inserted,
 129                                    struct buffer_head **bh)
 130 {
 131         struct buffer_head *cur = cur_bi->bi_bh;
 132         struct block_head *blkh;
 133         int nr;
 134         struct reiserfs_key *ih;
 135         struct disk_child new_dc[2];
 136         struct disk_child *dc;
 137         int i;
 138
 139         if (count <= 0)
 140                 return;
 141
 142         blkh = B_BLK_HEAD(cur);
 143         nr = blkh_nr_item(blkh);
 144
 145         RFALSE(count > 2, "too many children (%d) are to be inserted", count);
 146         RFALSE(B_FREE_SPACE(cur) < count * (KEY_SIZE + DC_SIZE),
 147                "no enough free space (%d), needed %d bytes",
 148                B_FREE_SPACE(cur), count * (KEY_SIZE + DC_SIZE));
 149
 150         /* prepare space for count disk_child */
 151         dc = B_N_CHILD(cur, to + 1);
 152
 153         memmove(dc + count, dc, (nr + 1 - (to + 1)) * DC_SIZE);
 154
 155         /* copy to_be_insert disk children */
 156         for (i = 0; i < count; i++) {
 157                 put_dc_size(&new_dc[i],
 158                             MAX_CHILD_SIZE(bh[i]) - B_FREE_SPACE(bh[i]));
 159                 put_dc_block_number(&new_dc[i], bh[i]->b_blocknr);
 160         }
 161         memcpy(dc, new_dc, DC_SIZE * count);
 162
 163         /* prepare space for count items  */
 164         ih = internal_key(cur, ((to == -1) ? 0 : to));
 165
 166         memmove(ih + count, ih,
 167                 (nr - to) * KEY_SIZE + (nr + 1 + count) * DC_SIZE);
 168
 169         /* copy item headers (keys) */
 170         memcpy(ih, inserted, KEY_SIZE);
 171         if (count > 1)
 172                 memcpy(ih + 1, inserted + 1, KEY_SIZE);
 173
 174         /* sizes, item number */
 175         set_blkh_nr_item(blkh, blkh_nr_item(blkh) + count);
 176         set_blkh_free_space(blkh,
 177                             blkh_free_space(blkh) - count * (DC_SIZE +
 178                                                              KEY_SIZE));
 179
 180         do_balance_mark_internal_dirty(cur_bi->tb, cur, 0);
 181
 182         /*&&&&&&&&&&&&&&&&&&&&&&&& */
 183         check_internal(cur);
 184         /*&&&&&&&&&&&&&&&&&&&&&&&& */
 185
 186         if (cur_bi->bi_parent) {
 187                 struct disk_child *t_dc =
 188                     B_N_CHILD(cur_bi->bi_parent, cur_bi->bi_position);
 189                 put_dc_size(t_dc,
 190                             dc_size(t_dc) + (count * (DC_SIZE + KEY_SIZE)));
 191                 do_balance_mark_internal_dirty(cur_bi->tb, cur_bi->bi_parent,
 192                                                0);
 193
 194                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
 195                 check_internal(cur_bi->bi_parent);
 196                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
 197         }
 198
 199 }
 200
 201 /*
 202  * Delete del_num items and node pointers from buffer cur starting from
 203  * the first_i'th item and first_p'th pointers respectively.
 204  */
 205 static void internal_delete_pointers_items(struct buffer_info *cur_bi,
 206                                            int first_p,
 207                                            int first_i, int del_num)
 208 {
 209         struct buffer_head *cur = cur_bi->bi_bh;
 210         int nr;
 211         struct block_head *blkh;
 212         struct reiserfs_key *key;
 213         struct disk_child *dc;
 214
 215         RFALSE(cur == NULL, "buffer is 0");
 216         RFALSE(del_num < 0,
 217                "negative number of items (%d) can not be deleted", del_num);
 218         RFALSE(first_p < 0 || first_p + del_num > B_NR_ITEMS(cur) + 1
 219                || first_i < 0,
 220                "first pointer order (%d) < 0 or "
 221                "no so many pointers (%d), only (%d) or "
 222                "first key order %d < 0", first_p, first_p + del_num,
 223                B_NR_ITEMS(cur) + 1, first_i);
 224         if (del_num == 0)
 225                 return;
 226
 227         blkh = B_BLK_HEAD(cur);
 228         nr = blkh_nr_item(blkh);
 229
 230         if (first_p == 0 && del_num == nr + 1) {
 231                 RFALSE(first_i != 0,
 232                        "1st deleted key must have order 0, not %d", first_i);
 233                 make_empty_node(cur_bi);
 234                 return;
 235         }
 236
 237         RFALSE(first_i + del_num > B_NR_ITEMS(cur),
 238                "first_i = %d del_num = %d "
 239                "no so many keys (%d) in the node (%b)(%z)",
 240                first_i, del_num, first_i + del_num, cur, cur);
 241
 242         /* deleting */
 243         dc = B_N_CHILD(cur, first_p);
 244
 245         memmove(dc, dc + del_num, (nr + 1 - first_p - del_num) * DC_SIZE);
 246         key = internal_key(cur, first_i);
 247         memmove(key, key + del_num,
 248                 (nr - first_i - del_num) * KEY_SIZE + (nr + 1 -
 249                                                        del_num) * DC_SIZE);
 250
 251         /* sizes, item number */
 252         set_blkh_nr_item(blkh, blkh_nr_item(blkh) - del_num);
 253         set_blkh_free_space(blkh,
 254                             blkh_free_space(blkh) +
 255                             (del_num * (KEY_SIZE + DC_SIZE)));
 256
 257         do_balance_mark_internal_dirty(cur_bi->tb, cur, 0);
 258         /*&&&&&&&&&&&&&&&&&&&&&&& */
 259         check_internal(cur);
 260         /*&&&&&&&&&&&&&&&&&&&&&&& */
 261
 262         if (cur_bi->bi_parent) {
 263                 struct disk_child *t_dc;
 264                 t_dc = B_N_CHILD(cur_bi->bi_parent, cur_bi->bi_position);
 265                 put_dc_size(t_dc,
 266                             dc_size(t_dc) - (del_num * (KEY_SIZE + DC_SIZE)));
 267
 268                 do_balance_mark_internal_dirty(cur_bi->tb, cur_bi->bi_parent,
 269                                                0);
 270                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
 271                 check_internal(cur_bi->bi_parent);
 272                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
 273         }
 274 }
 275
 276 /* delete n node pointers and items starting from given position */
 277 static void internal_delete_childs(struct buffer_info *cur_bi, int from, int n)
 278 {
 279         int i_from;
 280
 281         i_from = (from == 0) ? from : from - 1;
 282
 283         /*
 284          * delete n pointers starting from `from' position in CUR;
 285          * delete n keys starting from 'i_from' position in CUR;
 286          */
 287         internal_delete_pointers_items(cur_bi, from, i_from, n);
 288 }
 289
 290 /*
 291  * copy cpy_num node pointers and cpy_num - 1 items from buffer src to buffer
 292  * dest
 293  * last_first == FIRST_TO_LAST means that we copy first items
 294  *                             from src to tail of dest
 295  * last_first == LAST_TO_FIRST means that we copy last items
 296  *                             from src to head of dest
 297  */
 298 static void internal_copy_pointers_items(struct buffer_info *dest_bi,
 299                                          struct buffer_head *src,
 300                                          int last_first, int cpy_num)
 301 {
 302         /*
 303          * ATTENTION! Number of node pointers in DEST is equal to number
 304          * of items in DEST  as delimiting key have already inserted to
 305          * buffer dest.
 306          */
 307         struct buffer_head *dest = dest_bi->bi_bh;
 308         int nr_dest, nr_src;
 309         int dest_order, src_order;
 310         struct block_head *blkh;
 311         struct reiserfs_key *key;
 312         struct disk_child *dc;
 313
 314         nr_src = B_NR_ITEMS(src);
 315
 316         RFALSE(dest == NULL || src == NULL,
 317                "src (%p) or dest (%p) buffer is 0", src, dest);
 318         RFALSE(last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST,
 319                "invalid last_first parameter (%d)", last_first);
 320         RFALSE(nr_src < cpy_num - 1,
 321                "no so many items (%d) in src (%d)", cpy_num, nr_src);
 322         RFALSE(cpy_num < 0, "cpy_num less than 0 (%d)", cpy_num);
 323         RFALSE(cpy_num - 1 + B_NR_ITEMS(dest) > (int)MAX_NR_KEY(dest),
 324                "cpy_num (%d) + item number in dest (%d) can not be > MAX_NR_KEY(%d)",
 325                cpy_num, B_NR_ITEMS(dest), MAX_NR_KEY(dest));
 326
 327         if (cpy_num == 0)
 328                 return;
 329
 330         /* coping */
 331         blkh = B_BLK_HEAD(dest);
 332         nr_dest = blkh_nr_item(blkh);
 333
 334         /*dest_order = (last_first == LAST_TO_FIRST) ? 0 : nr_dest; */
 335         /*src_order = (last_first == LAST_TO_FIRST) ? (nr_src - cpy_num + 1) : 0; */
 336         (last_first == LAST_TO_FIRST) ? (dest_order = 0, src_order =
 337                                          nr_src - cpy_num + 1) : (dest_order =
 338                                                                   nr_dest,
 339                                                                   src_order =
 340                                                                   0);
 341
 342         /* prepare space for cpy_num pointers */
 343         dc = B_N_CHILD(dest, dest_order);
 344
 345         memmove(dc + cpy_num, dc, (nr_dest - dest_order) * DC_SIZE);
 346
 347         /* insert pointers */
 348         memcpy(dc, B_N_CHILD(src, src_order), DC_SIZE * cpy_num);
 349
 350         /* prepare space for cpy_num - 1 item headers */
 351         key = internal_key(dest, dest_order);
 352         memmove(key + cpy_num - 1, key,
 353                 KEY_SIZE * (nr_dest - dest_order) + DC_SIZE * (nr_dest +
 354                                                                cpy_num));
 355
 356         /* insert headers */
 357         memcpy(key, internal_key(src, src_order), KEY_SIZE * (cpy_num - 1));
 358
 359         /* sizes, item number */
 360         set_blkh_nr_item(blkh, blkh_nr_item(blkh) + (cpy_num - 1));
 361         set_blkh_free_space(blkh,
 362                             blkh_free_space(blkh) - (KEY_SIZE * (cpy_num - 1) +
 363                                                      DC_SIZE * cpy_num));
 364
 365         do_balance_mark_internal_dirty(dest_bi->tb, dest, 0);
 366
 367         /*&&&&&&&&&&&&&&&&&&&&&&&& */
 368         check_internal(dest);
 369         /*&&&&&&&&&&&&&&&&&&&&&&&& */
 370
 371         if (dest_bi->bi_parent) {
 372                 struct disk_child *t_dc;
 373                 t_dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
 374                 put_dc_size(t_dc,
 375                             dc_size(t_dc) + (KEY_SIZE * (cpy_num - 1) +
 376                                              DC_SIZE * cpy_num));
 377
 378                 do_balance_mark_internal_dirty(dest_bi->tb, dest_bi->bi_parent,
 379                                                0);
 380                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
 381                 check_internal(dest_bi->bi_parent);
 382                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
 383         }
 384
 385 }
 386
 387 /*
 388  * Copy cpy_num node pointers and cpy_num - 1 items from buffer src to
 389  * buffer dest.
 390  * Delete cpy_num - del_par items and node pointers from buffer src.
 391  * last_first == FIRST_TO_LAST means, that we copy/delete first items from src.
 392  * last_first == LAST_TO_FIRST means, that we copy/delete last items from src.
 393  */
 394 static void internal_move_pointers_items(struct buffer_info *dest_bi,
 395                                          struct buffer_info *src_bi,
 396                                          int last_first, int cpy_num,
 397                                          int del_par)
 398 {
 399         int first_pointer;
 400         int first_item;
 401
 402         internal_copy_pointers_items(dest_bi, src_bi->bi_bh, last_first,
 403                                      cpy_num);
 404
 405         if (last_first == FIRST_TO_LAST) {      /* shift_left occurs */
 406                 first_pointer = 0;
 407                 first_item = 0;
 408                 /*
 409                  * delete cpy_num - del_par pointers and keys starting for
 410                  * pointers with first_pointer, for key - with first_item
 411                  */
 412                 internal_delete_pointers_items(src_bi, first_pointer,
 413                                                first_item, cpy_num - del_par);
 414         } else {                /* shift_right occurs */
 415                 int i, j;
 416
 417                 i = (cpy_num - del_par ==
 418                      (j =
 419                       B_NR_ITEMS(src_bi->bi_bh)) + 1) ? 0 : j - cpy_num +
 420                     del_par;
 421
 422                 internal_delete_pointers_items(src_bi,
 423                                                j + 1 - cpy_num + del_par, i,
 424                                                cpy_num - del_par);
 425         }
 426 }
 427
 428 /* Insert n_src'th key of buffer src before n_dest'th key of buffer dest. */
 429 static void internal_insert_key(struct buffer_info *dest_bi,
 430                                 /* insert key before key with n_dest number */
 431                                 int dest_position_before,
 432                                 struct buffer_head *src, int src_position)
 433 {
 434         struct buffer_head *dest = dest_bi->bi_bh;
 435         int nr;
 436         struct block_head *blkh;
 437         struct reiserfs_key *key;
 438
 439         RFALSE(dest == NULL || src == NULL,
 440                "source(%p) or dest(%p) buffer is 0", src, dest);
 441         RFALSE(dest_position_before < 0 || src_position < 0,
 442                "source(%d) or dest(%d) key number less than 0",
 443                src_position, dest_position_before);
 444         RFALSE(dest_position_before > B_NR_ITEMS(dest) ||
 445                src_position >= B_NR_ITEMS(src),
 446                "invalid position in dest (%d (key number %d)) or in src (%d (key number %d))",
 447                dest_position_before, B_NR_ITEMS(dest),
 448                src_position, B_NR_ITEMS(src));
 449         RFALSE(B_FREE_SPACE(dest) < KEY_SIZE,
 450                "no enough free space (%d) in dest buffer", B_FREE_SPACE(dest));
 451
 452         blkh = B_BLK_HEAD(dest);
 453         nr = blkh_nr_item(blkh);
 454
 455         /* prepare space for inserting key */
 456         key = internal_key(dest, dest_position_before);
 457         memmove(key + 1, key,
 458                 (nr - dest_position_before) * KEY_SIZE + (nr + 1) * DC_SIZE);
 459
 460         /* insert key */
 461         memcpy(key, internal_key(src, src_position), KEY_SIZE);
 462
 463         /* Change dirt, free space, item number fields. */
 464
 465         set_blkh_nr_item(blkh, blkh_nr_item(blkh) + 1);
 466         set_blkh_free_space(blkh, blkh_free_space(blkh) - KEY_SIZE);
 467
 468         do_balance_mark_internal_dirty(dest_bi->tb, dest, 0);
 469
 470         if (dest_bi->bi_parent) {
 471                 struct disk_child *t_dc;
 472                 t_dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
 473                 put_dc_size(t_dc, dc_size(t_dc) + KEY_SIZE);
 474
 475                 do_balance_mark_internal_dirty(dest_bi->tb, dest_bi->bi_parent,
 476                                                0);
 477         }
 478 }
 479
 480 /*
 481  * Insert d_key'th (delimiting) key from buffer cfl to tail of dest.
 482  * Copy pointer_amount node pointers and pointer_amount - 1 items from
 483  * buffer src to buffer dest.
 484  * Replace  d_key'th key in buffer cfl.
 485  * Delete pointer_amount items and node pointers from buffer src.
 486  */
 487 /* this can be invoked both to shift from S to L and from R to S */
 488 static void internal_shift_left(
 489                                 /*
 490                                  * INTERNAL_FROM_S_TO_L | INTERNAL_FROM_R_TO_S
 491                                  */
 492                                 int mode,
 493                                 struct tree_balance *tb,
 494                                 int h, int pointer_amount)
 495 {
 496         struct buffer_info dest_bi, src_bi;
 497         struct buffer_head *cf;
 498         int d_key_position;
 499
 500         internal_define_dest_src_infos(mode, tb, h, &dest_bi, &src_bi,
 501                                        &d_key_position, &cf);
 502
 503         /*printk("pointer_amount = %d\n",pointer_amount); */
 504
 505         if (pointer_amount) {
 506                 /*
 507                  * insert delimiting key from common father of dest and
 508                  * src to node dest into position B_NR_ITEM(dest)
 509                  */
 510                 internal_insert_key(&dest_bi, B_NR_ITEMS(dest_bi.bi_bh), cf,
 511                                     d_key_position);
 512
 513                 if (B_NR_ITEMS(src_bi.bi_bh) == pointer_amount - 1) {
 514                         if (src_bi.bi_position /*src->b_item_order */  == 0)
 515                                 replace_key(tb, cf, d_key_position,
 516                                             src_bi.
 517                                             bi_parent /*src->b_parent */ , 0);
 518                 } else
 519                         replace_key(tb, cf, d_key_position, src_bi.bi_bh,
 520                                     pointer_amount - 1);
 521         }
 522         /* last parameter is del_parameter */
 523         internal_move_pointers_items(&dest_bi, &src_bi, FIRST_TO_LAST,
 524                                      pointer_amount, 0);
 525
 526 }
 527
 528 /*
 529  * Insert delimiting key to L[h].
 530  * Copy n node pointers and n - 1 items from buffer S[h] to L[h].
 531  * Delete n - 1 items and node pointers from buffer S[h].
 532  */
 533 /* it always shifts from S[h] to L[h] */
 534 static void internal_shift1_left(struct tree_balance *tb,
 535                                  int h, int pointer_amount)
 536 {
 537         struct buffer_info dest_bi, src_bi;
 538         struct buffer_head *cf;
 539         int d_key_position;
 540
 541         internal_define_dest_src_infos(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
 542                                        &dest_bi, &src_bi, &d_key_position, &cf);
 543
 544         /* insert lkey[h]-th key  from CFL[h] to left neighbor L[h] */
 545         if (pointer_amount > 0)
 546                 internal_insert_key(&dest_bi, B_NR_ITEMS(dest_bi.bi_bh), cf,
 547                                     d_key_position);
 548
 549         /* last parameter is del_parameter */
 550         internal_move_pointers_items(&dest_bi, &src_bi, FIRST_TO_LAST,
 551                                      pointer_amount, 1);
 552 }
 553
 554 /*
 555  * Insert d_key'th (delimiting) key from buffer cfr to head of dest.
 556  * Copy n node pointers and n - 1 items from buffer src to buffer dest.
 557  * Replace  d_key'th key in buffer cfr.
 558  * Delete n items and node pointers from buffer src.
 559  */
 560 static void internal_shift_right(
 561                                  /*
 562                                   * INTERNAL_FROM_S_TO_R | INTERNAL_FROM_L_TO_S
 563                                   */
 564                                  int mode,
 565                                  struct tree_balance *tb,
 566                                  int h, int pointer_amount)
 567 {
 568         struct buffer_info dest_bi, src_bi;
 569         struct buffer_head *cf;
 570         int d_key_position;
 571         int nr;
 572
 573         internal_define_dest_src_infos(mode, tb, h, &dest_bi, &src_bi,
 574                                        &d_key_position, &cf);
 575
 576         nr = B_NR_ITEMS(src_bi.bi_bh);
 577
 578         if (pointer_amount > 0) {
 579                 /*
 580                  * insert delimiting key from common father of dest
 581                  * and src to dest node into position 0
 582                  */
 583                 internal_insert_key(&dest_bi, 0, cf, d_key_position);
 584                 if (nr == pointer_amount - 1) {
 585                         RFALSE(src_bi.bi_bh != PATH_H_PBUFFER(tb->tb_path, h) /*tb->S[h] */ ||
 586                                dest_bi.bi_bh != tb->R[h],
 587                                "src (%p) must be == tb->S[h](%p) when it disappears",
 588                                src_bi.bi_bh, PATH_H_PBUFFER(tb->tb_path, h));
 589                         /* when S[h] disappers replace left delemiting key as well */
 590                         if (tb->CFL[h])
 591                                 replace_key(tb, cf, d_key_position, tb->CFL[h],
 592                                             tb->lkey[h]);
 593                 } else
 594                         replace_key(tb, cf, d_key_position, src_bi.bi_bh,
 595                                     nr - pointer_amount);
 596         }
 597
 598         /* last parameter is del_parameter */
 599         internal_move_pointers_items(&dest_bi, &src_bi, LAST_TO_FIRST,
 600                                      pointer_amount, 0);
 601 }
 602
 603 /*
 604  * Insert delimiting key to R[h].
 605  * Copy n node pointers and n - 1 items from buffer S[h] to R[h].
 606  * Delete n - 1 items and node pointers from buffer S[h].
 607  */
 608 /* it always shift from S[h] to R[h] */
 609 static void internal_shift1_right(struct tree_balance *tb,
 610                                   int h, int pointer_amount)
 611 {
 612         struct buffer_info dest_bi, src_bi;
 613         struct buffer_head *cf;
 614         int d_key_position;
 615
 616         internal_define_dest_src_infos(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
 617                                        &dest_bi, &src_bi, &d_key_position, &cf);
 618
 619         /* insert rkey from CFR[h] to right neighbor R[h] */
 620         if (pointer_amount > 0)
 621                 internal_insert_key(&dest_bi, 0, cf, d_key_position);
 622
 623         /* last parameter is del_parameter */
 624         internal_move_pointers_items(&dest_bi, &src_bi, LAST_TO_FIRST,
 625                                      pointer_amount, 1);
 626 }
 627
 628 /*
 629  * Delete insert_num node pointers together with their left items
 630  * and balance current node.
 631  */
 632 static void balance_internal_when_delete(struct tree_balance *tb,
 633                                          int h, int child_pos)
 634 {
 635         int insert_num;
 636         int n;
 637         struct buffer_head *tbSh = PATH_H_PBUFFER(tb->tb_path, h);
 638         struct buffer_info bi;
 639
 640         insert_num = tb->insert_size[h] / ((int)(DC_SIZE + KEY_SIZE));
 641
 642         /* delete child-node-pointer(s) together with their left item(s) */
 643         bi.tb = tb;
 644         bi.bi_bh = tbSh;
 645         bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
 646         bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
 647
 648         internal_delete_childs(&bi, child_pos, -insert_num);
 649
 650         RFALSE(tb->blknum[h] > 1,
 651                "tb->blknum[%d]=%d when insert_size < 0", h, tb->blknum[h]);
 652
 653         n = B_NR_ITEMS(tbSh);
 654
 655         if (tb->lnum[h] == 0 && tb->rnum[h] == 0) {
 656                 if (tb->blknum[h] == 0) {
 657                         /* node S[h] (root of the tree) is empty now */
 658                         struct buffer_head *new_root;
 659
 660                         RFALSE(n
 661                                || B_FREE_SPACE(tbSh) !=
 662                                MAX_CHILD_SIZE(tbSh) - DC_SIZE,
 663                                "buffer must have only 0 keys (%d)", n);
 664                         RFALSE(bi.bi_parent, "root has parent (%p)",
 665                                bi.bi_parent);
 666
 667                         /* choose a new root */
 668                         if (!tb->L[h - 1] || !B_NR_ITEMS(tb->L[h - 1]))
 669                                 new_root = tb->R[h - 1];
 670                         else
 671                                 new_root = tb->L[h - 1];
 672                         /*
 673                          * switch super block's tree root block
 674                          * number to the new value */
 675                         PUT_SB_ROOT_BLOCK(tb->tb_sb, new_root->b_blocknr);
 676                         /*REISERFS_SB(tb->tb_sb)->s_rs->s_tree_height --; */
 677                         PUT_SB_TREE_HEIGHT(tb->tb_sb,
 678                                            SB_TREE_HEIGHT(tb->tb_sb) - 1);
 679
 680                         do_balance_mark_sb_dirty(tb,
 681                                                  REISERFS_SB(tb->tb_sb)->s_sbh,
 682                                                  1);
 683                         /*&&&&&&&&&&&&&&&&&&&&&& */
 684                         /* use check_internal if new root is an internal node */
 685                         if (h > 1)
 686                                 check_internal(new_root);
 687                         /*&&&&&&&&&&&&&&&&&&&&&& */
 688
 689                         /* do what is needed for buffer thrown from tree */
 690                         reiserfs_invalidate_buffer(tb, tbSh);
 691                         return;
 692                 }
 693                 return;
 694         }
 695
 696         /* join S[h] with L[h] */
 697         if (tb->L[h] && tb->lnum[h] == -B_NR_ITEMS(tb->L[h]) - 1) {
 698
 699                 RFALSE(tb->rnum[h] != 0,
 700                        "invalid tb->rnum[%d]==%d when joining S[h] with L[h]",
 701                        h, tb->rnum[h]);
 702
 703                 internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h, n + 1);
 704                 reiserfs_invalidate_buffer(tb, tbSh);
 705
 706                 return;
 707         }
 708
 709         /* join S[h] with R[h] */
 710         if (tb->R[h] && tb->rnum[h] == -B_NR_ITEMS(tb->R[h]) - 1) {
 711                 RFALSE(tb->lnum[h] != 0,
 712                        "invalid tb->lnum[%d]==%d when joining S[h] with R[h]",
 713                        h, tb->lnum[h]);
 714
 715                 internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h, n + 1);
 716
 717                 reiserfs_invalidate_buffer(tb, tbSh);
 718                 return;
 719         }
 720
 721         /* borrow from left neighbor L[h] */
 722         if (tb->lnum[h] < 0) {
 723                 RFALSE(tb->rnum[h] != 0,
 724                        "wrong tb->rnum[%d]==%d when borrow from L[h]", h,
 725                        tb->rnum[h]);
 726                 internal_shift_right(INTERNAL_SHIFT_FROM_L_TO_S, tb, h,
 727                                      -tb->lnum[h]);
 728                 return;
 729         }
 730
 731         /* borrow from right neighbor R[h] */
 732         if (tb->rnum[h] < 0) {
 733                 RFALSE(tb->lnum[h] != 0,
 734                        "invalid tb->lnum[%d]==%d when borrow from R[h]",
 735                        h, tb->lnum[h]);
 736                 internal_shift_left(INTERNAL_SHIFT_FROM_R_TO_S, tb, h, -tb->rnum[h]);   /*tb->S[h], tb->CFR[h], tb->rkey[h], tb->R[h], -tb->rnum[h]); */
 737                 return;
 738         }
 739
 740         /* split S[h] into two parts and put them into neighbors */
 741         if (tb->lnum[h] > 0) {
 742                 RFALSE(tb->rnum[h] == 0 || tb->lnum[h] + tb->rnum[h] != n + 1,
 743                        "invalid tb->lnum[%d]==%d or tb->rnum[%d]==%d when S[h](item number == %d) is split between them",
 744                        h, tb->lnum[h], h, tb->rnum[h], n);
 745
 746                 internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h, tb->lnum[h]);    /*tb->L[h], tb->CFL[h], tb->lkey[h], tb->S[h], tb->lnum[h]); */
 747                 internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
 748                                      tb->rnum[h]);
 749
 750                 reiserfs_invalidate_buffer(tb, tbSh);
 751
 752                 return;
 753         }
 754         reiserfs_panic(tb->tb_sb, "ibalance-2",
 755                        "unexpected tb->lnum[%d]==%d or tb->rnum[%d]==%d",
 756                        h, tb->lnum[h], h, tb->rnum[h]);
 757 }
 758
 759 /* Replace delimiting key of buffers L[h] and S[h] by the given key.*/
 760 static void replace_lkey(struct tree_balance *tb, int h, struct item_head *key)
 761 {
 762         RFALSE(tb->L[h] == NULL || tb->CFL[h] == NULL,
 763                "L[h](%p) and CFL[h](%p) must exist in replace_lkey",
 764                tb->L[h], tb->CFL[h]);
 765
 766         if (B_NR_ITEMS(PATH_H_PBUFFER(tb->tb_path, h)) == 0)
 767                 return;
 768
 769         memcpy(internal_key(tb->CFL[h], tb->lkey[h]), key, KEY_SIZE);
 770
 771         do_balance_mark_internal_dirty(tb, tb->CFL[h], 0);
 772 }
 773
 774 /* Replace delimiting key of buffers S[h] and R[h] by the given key.*/
 775 static void replace_rkey(struct tree_balance *tb, int h, struct item_head *key)
 776 {
 777         RFALSE(tb->R[h] == NULL || tb->CFR[h] == NULL,
 778                "R[h](%p) and CFR[h](%p) must exist in replace_rkey",
 779                tb->R[h], tb->CFR[h]);
 780         RFALSE(B_NR_ITEMS(tb->R[h]) == 0,
 781                "R[h] can not be empty if it exists (item number=%d)",
 782                B_NR_ITEMS(tb->R[h]));
 783
 784         memcpy(internal_key(tb->CFR[h], tb->rkey[h]), key, KEY_SIZE);
 785
 786         do_balance_mark_internal_dirty(tb, tb->CFR[h], 0);
 787 }
 788
 789
 790 /*
 791  * if inserting/pasting {
 792  *   child_pos is the position of the node-pointer in S[h] that
 793  *   pointed to S[h-1] before balancing of the h-1 level;
 794  *   this means that new pointers and items must be inserted AFTER
 795  *   child_pos
 796  * } else {
 797  *   it is the position of the leftmost pointer that must be deleted
 798  *   (together with its corresponding key to the left of the pointer)
 799  *   as a result of the previous level's balancing.
 800  * }
 801  */
 802
 803 int balance_internal(struct tree_balance *tb,
 804                      int h,     /* level of the tree */
 805                      int child_pos,
 806                      /* key for insertion on higher level    */
 807                      struct item_head *insert_key,
 808                      /* node for insertion on higher level */
 809                      struct buffer_head **insert_ptr)
 810 {
 811         struct buffer_head *tbSh = PATH_H_PBUFFER(tb->tb_path, h);
 812         struct buffer_info bi;
 813
 814         /*
 815          * we return this: it is 0 if there is no S[h],
 816          * else it is tb->S[h]->b_item_order
 817          */
 818         int order;
 819         int insert_num, n, k;
 820         struct buffer_head *S_new;
 821         struct item_head new_insert_key;
 822         struct buffer_head *new_insert_ptr = NULL;
 823         struct item_head *new_insert_key_addr = insert_key;
 824
 825         RFALSE(h < 1, "h (%d) can not be < 1 on internal level", h);
 826
 827         PROC_INFO_INC(tb->tb_sb, balance_at[h]);
 828
 829         order =
 830             (tbSh) ? PATH_H_POSITION(tb->tb_path,
 831                                      h + 1) /*tb->S[h]->b_item_order */ : 0;
 832
 833         /*
 834          * Using insert_size[h] calculate the number insert_num of items
 835          * that must be inserted to or deleted from S[h].
 836          */
 837         insert_num = tb->insert_size[h] / ((int)(KEY_SIZE + DC_SIZE));
 838
 839         /* Check whether insert_num is proper * */
 840         RFALSE(insert_num < -2 || insert_num > 2,
 841                "incorrect number of items inserted to the internal node (%d)",
 842                insert_num);
 843         RFALSE(h > 1 && (insert_num > 1 || insert_num < -1),
 844                "incorrect number of items (%d) inserted to the internal node on a level (h=%d) higher than last internal level",
 845                insert_num, h);
 846
 847         /* Make balance in case insert_num < 0 */
 848         if (insert_num < 0) {
 849                 balance_internal_when_delete(tb, h, child_pos);
 850                 return order;
 851         }
 852
 853         k = 0;
 854         if (tb->lnum[h] > 0) {
 855                 /*
 856                  * shift lnum[h] items from S[h] to the left neighbor L[h].
 857                  * check how many of new items fall into L[h] or CFL[h] after
 858                  * shifting
 859                  */
 860                 n = B_NR_ITEMS(tb->L[h]);       /* number of items in L[h] */
 861                 if (tb->lnum[h] <= child_pos) {
 862                         /* new items don't fall into L[h] or CFL[h] */
 863                         internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
 864                                             tb->lnum[h]);
 865                         child_pos -= tb->lnum[h];
 866                 } else if (tb->lnum[h] > child_pos + insert_num) {
 867                         /* all new items fall into L[h] */
 868                         internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
 869                                             tb->lnum[h] - insert_num);
 870                         /* insert insert_num keys and node-pointers into L[h] */
 871                         bi.tb = tb;
 872                         bi.bi_bh = tb->L[h];
 873                         bi.bi_parent = tb->FL[h];
 874                         bi.bi_position = get_left_neighbor_position(tb, h);
 875                         internal_insert_childs(&bi,
 876                                                /*tb->L[h], tb->S[h-1]->b_next */
 877                                                n + child_pos + 1,
 878                                                insert_num, insert_key,
 879                                                insert_ptr);
 880
 881                         insert_num = 0;
 882                 } else {
 883                         struct disk_child *dc;
 884
 885                         /*
 886                          * some items fall into L[h] or CFL[h],
 887                          * but some don't fall
 888                          */
 889                         internal_shift1_left(tb, h, child_pos + 1);
 890                         /* calculate number of new items that fall into L[h] */
 891                         k = tb->lnum[h] - child_pos - 1;
 892                         bi.tb = tb;
 893                         bi.bi_bh = tb->L[h];
 894                         bi.bi_parent = tb->FL[h];
 895                         bi.bi_position = get_left_neighbor_position(tb, h);
 896                         internal_insert_childs(&bi,
 897                                                /*tb->L[h], tb->S[h-1]->b_next, */
 898                                                n + child_pos + 1, k,
 899                                                insert_key, insert_ptr);
 900
 901                         replace_lkey(tb, h, insert_key + k);
 902
 903                         /*
 904                          * replace the first node-ptr in S[h] by
 905                          * node-ptr to insert_ptr[k]
 906                          */
 907                         dc = B_N_CHILD(tbSh, 0);
 908                         put_dc_size(dc,
 909                                     MAX_CHILD_SIZE(insert_ptr[k]) -
 910                                     B_FREE_SPACE(insert_ptr[k]));
 911                         put_dc_block_number(dc, insert_ptr[k]->b_blocknr);
 912
 913                         do_balance_mark_internal_dirty(tb, tbSh, 0);
 914
 915                         k++;
 916                         insert_key += k;
 917                         insert_ptr += k;
 918                         insert_num -= k;
 919                         child_pos = 0;
 920                 }
 921         }
 922         /* tb->lnum[h] > 0 */
 923         if (tb->rnum[h] > 0) {
 924                 /*shift rnum[h] items from S[h] to the right neighbor R[h] */
 925                 /*
 926                  * check how many of new items fall into R or CFR
 927                  * after shifting
 928                  */
 929                 n = B_NR_ITEMS(tbSh);   /* number of items in S[h] */
 930                 if (n - tb->rnum[h] >= child_pos)
 931                         /* new items fall into S[h] */
 932                         internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
 933                                              tb->rnum[h]);
 934                 else if (n + insert_num - tb->rnum[h] < child_pos) {
 935                         /* all new items fall into R[h] */
 936                         internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
 937                                              tb->rnum[h] - insert_num);
 938
 939                         /* insert insert_num keys and node-pointers into R[h] */
 940                         bi.tb = tb;
 941                         bi.bi_bh = tb->R[h];
 942                         bi.bi_parent = tb->FR[h];
 943                         bi.bi_position = get_right_neighbor_position(tb, h);
 944                         internal_insert_childs(&bi,
 945                                                /*tb->R[h],tb->S[h-1]->b_next */
 946                                                child_pos - n - insert_num +
 947                                                tb->rnum[h] - 1,
 948                                                insert_num, insert_key,
 949                                                insert_ptr);
 950                         insert_num = 0;
 951                 } else {
 952                         struct disk_child *dc;
 953
 954                         /* one of the items falls into CFR[h] */
 955                         internal_shift1_right(tb, h, n - child_pos + 1);
 956                         /* calculate number of new items that fall into R[h] */
 957                         k = tb->rnum[h] - n + child_pos - 1;
 958                         bi.tb = tb;
 959                         bi.bi_bh = tb->R[h];
 960                         bi.bi_parent = tb->FR[h];
 961                         bi.bi_position = get_right_neighbor_position(tb, h);
 962                         internal_insert_childs(&bi,
 963                                                /*tb->R[h], tb->R[h]->b_child, */
 964                                                0, k, insert_key + 1,
 965                                                insert_ptr + 1);
 966
 967                         replace_rkey(tb, h, insert_key + insert_num - k - 1);
 968
 969                         /*
 970                          * replace the first node-ptr in R[h] by
 971                          * node-ptr insert_ptr[insert_num-k-1]
 972                          */
 973                         dc = B_N_CHILD(tb->R[h], 0);
 974                         put_dc_size(dc,
 975                                     MAX_CHILD_SIZE(insert_ptr
 976                                                    [insert_num - k - 1]) -
 977                                     B_FREE_SPACE(insert_ptr
 978                                                  [insert_num - k - 1]));
 979                         put_dc_block_number(dc,
 980                                             insert_ptr[insert_num - k -
 981                                                        1]->b_blocknr);
 982
 983                         do_balance_mark_internal_dirty(tb, tb->R[h], 0);
 984
 985                         insert_num -= (k + 1);
 986                 }
 987         }
 988
 989         /** Fill new node that appears instead of S[h] **/
 990         RFALSE(tb->blknum[h] > 2, "blknum can not be > 2 for internal level");
 991         RFALSE(tb->blknum[h] < 0, "blknum can not be < 0");
 992
 993         if (!tb->blknum[h]) {   /* node S[h] is empty now */
 994                 RFALSE(!tbSh, "S[h] is equal NULL");
 995
 996                 /* do what is needed for buffer thrown from tree */
 997                 reiserfs_invalidate_buffer(tb, tbSh);
 998                 return order;
 999         }
1000
1001         if (!tbSh) {
1002                 /* create new root */
1003                 struct disk_child *dc;
1004                 struct buffer_head *tbSh_1 = PATH_H_PBUFFER(tb->tb_path, h - 1);
1005                 struct block_head *blkh;
1006
1007                 if (tb->blknum[h] != 1)
1008                         reiserfs_panic(NULL, "ibalance-3", "One new node "
1009                                        "required for creating the new root");
1010                 /* S[h] = empty buffer from the list FEB. */
1011                 tbSh = get_FEB(tb);
1012                 blkh = B_BLK_HEAD(tbSh);
1013                 set_blkh_level(blkh, h + 1);
1014
1015                 /* Put the unique node-pointer to S[h] that points to S[h-1]. */
1016
1017                 dc = B_N_CHILD(tbSh, 0);
1018                 put_dc_block_number(dc, tbSh_1->b_blocknr);
1019                 put_dc_size(dc,
1020                             (MAX_CHILD_SIZE(tbSh_1) - B_FREE_SPACE(tbSh_1)));
1021
1022                 tb->insert_size[h] -= DC_SIZE;
1023                 set_blkh_free_space(blkh, blkh_free_space(blkh) - DC_SIZE);
1024
1025                 do_balance_mark_internal_dirty(tb, tbSh, 0);
1026
1027                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
1028                 check_internal(tbSh);
1029                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
1030
1031                 /* put new root into path structure */
1032                 PATH_OFFSET_PBUFFER(tb->tb_path, ILLEGAL_PATH_ELEMENT_OFFSET) =
1033                     tbSh;
1034
1035                 /* Change root in structure super block. */
1036                 PUT_SB_ROOT_BLOCK(tb->tb_sb, tbSh->b_blocknr);
1037                 PUT_SB_TREE_HEIGHT(tb->tb_sb, SB_TREE_HEIGHT(tb->tb_sb) + 1);
1038                 do_balance_mark_sb_dirty(tb, REISERFS_SB(tb->tb_sb)->s_sbh, 1);
1039         }
1040
1041         if (tb->blknum[h] == 2) {
1042                 int snum;
1043                 struct buffer_info dest_bi, src_bi;
1044
1045                 /* S_new = free buffer from list FEB */
1046                 S_new = get_FEB(tb);
1047
1048                 set_blkh_level(B_BLK_HEAD(S_new), h + 1);
1049
1050                 dest_bi.tb = tb;
1051                 dest_bi.bi_bh = S_new;
1052                 dest_bi.bi_parent = NULL;
1053                 dest_bi.bi_position = 0;
1054                 src_bi.tb = tb;
1055                 src_bi.bi_bh = tbSh;
1056                 src_bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
1057                 src_bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
1058
1059                 n = B_NR_ITEMS(tbSh);   /* number of items in S[h] */
1060                 snum = (insert_num + n + 1) / 2;
1061                 if (n - snum >= child_pos) {
1062                         /* new items don't fall into S_new */
1063                         /*  store the delimiting key for the next level */
1064                         /* new_insert_key = (n - snum)'th key in S[h] */
1065                         memcpy(&new_insert_key, internal_key(tbSh, n - snum),
1066                                KEY_SIZE);
1067                         /* last parameter is del_par */
1068                         internal_move_pointers_items(&dest_bi, &src_bi,
1069                                                      LAST_TO_FIRST, snum, 0);
1070                 } else if (n + insert_num - snum < child_pos) {
1071                         /* all new items fall into S_new */
1072                         /*  store the delimiting key for the next level */
1073                         /*
1074                          * new_insert_key = (n + insert_item - snum)'th
1075                          * key in S[h]
1076                          */
1077                         memcpy(&new_insert_key,
1078                                internal_key(tbSh, n + insert_num - snum),
1079                                KEY_SIZE);
1080                         /* last parameter is del_par */
1081                         internal_move_pointers_items(&dest_bi, &src_bi,
1082                                                      LAST_TO_FIRST,
1083                                                      snum - insert_num, 0);
1084
1085                         /*
1086                          * insert insert_num keys and node-pointers
1087                          * into S_new
1088                          */
1089                         internal_insert_childs(&dest_bi,
1090                                                /*S_new,tb->S[h-1]->b_next, */
1091                                                child_pos - n - insert_num +
1092                                                snum - 1,
1093                                                insert_num, insert_key,
1094                                                insert_ptr);
1095
1096                         insert_num = 0;
1097                 } else {
1098                         struct disk_child *dc;
1099
1100                         /* some items fall into S_new, but some don't fall */
1101                         /* last parameter is del_par */
1102                         internal_move_pointers_items(&dest_bi, &src_bi,
1103                                                      LAST_TO_FIRST,
1104                                                      n - child_pos + 1, 1);
1105                         /* calculate number of new items that fall into S_new */
1106                         k = snum - n + child_pos - 1;
1107
1108                         internal_insert_childs(&dest_bi, /*S_new, */ 0, k,
1109                                                insert_key + 1, insert_ptr + 1);
1110
1111                         /* new_insert_key = insert_key[insert_num - k - 1] */
1112                         memcpy(&new_insert_key, insert_key + insert_num - k - 1,
1113                                KEY_SIZE);
1114                         /*
1115                          * replace first node-ptr in S_new by node-ptr
1116                          * to insert_ptr[insert_num-k-1]
1117                          */
1118
1119                         dc = B_N_CHILD(S_new, 0);
1120                         put_dc_size(dc,
1121                                     (MAX_CHILD_SIZE
1122                                      (insert_ptr[insert_num - k - 1]) -
1123                                      B_FREE_SPACE(insert_ptr
1124                                                   [insert_num - k - 1])));
1125                         put_dc_block_number(dc,
1126                                             insert_ptr[insert_num - k -
1127                                                        1]->b_blocknr);
1128
1129                         do_balance_mark_internal_dirty(tb, S_new, 0);
1130
1131                         insert_num -= (k + 1);
1132                 }
1133                 /* new_insert_ptr = node_pointer to S_new */
1134                 new_insert_ptr = S_new;
1135
1136                 RFALSE(!buffer_journaled(S_new) || buffer_journal_dirty(S_new)
1137                        || buffer_dirty(S_new), "cm-00001: bad S_new (%b)",
1138                        S_new);
1139
1140                 /* S_new is released in unfix_nodes */
1141         }
1142
1143         n = B_NR_ITEMS(tbSh);   /*number of items in S[h] */
1144
1145         if (0 <= child_pos && child_pos <= n && insert_num > 0) {
1146                 bi.tb = tb;
1147                 bi.bi_bh = tbSh;
1148                 bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
1149                 bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
1150                 internal_insert_childs(&bi,     /*tbSh, */
1151                                        /*          ( tb->S[h-1]->b_parent == tb->S[h] ) ? tb->S[h-1]->b_next :  tb->S[h]->b_child->b_next, */
1152                                        child_pos, insert_num, insert_key,
1153                                        insert_ptr);
1154         }
1155
1156         insert_ptr[0] = new_insert_ptr;
1157         if (new_insert_ptr)
1158                 memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE);
1159
1160         return order;
1161 }