fs/reiserfs/do_balan.c

   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
  19 static 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
  28 static 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
  37 static 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
  46 static 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
  56 inline 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  */
  99 static 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
 293 static 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
 351 static 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
 511 static 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
 585 static 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
 736 static 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
 807 static 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
 965 static 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
 985 static 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  */
1075 static 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 */
1256 void 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 */
1271 struct 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. */
1293 static 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
1310 static 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
1328 void 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.*/
1340 void 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
1367 int 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
1381 int 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
1397 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value);
1398 static 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
1424 static 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
1435 static 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
1470 static 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
1518 static 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
1525 static 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
1577 static 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
1594 static 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  */
1635 void 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 }