git.oblomov.eu Git - linux-2.6/blob - fs/reiserfs/do_balan.c

   1 /*
   2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
   3  */
   4
   5 /* Now we have all buffers that must be used in balancing of the tree   */
   6 /* Further calculations can not cause schedule(), and thus the buffer   */
   7 /* tree will be stable until the balancing will be finished             */
   8 /* balance the tree according to the analysis made before,              */
   9 /* and using buffers obtained after all above.                          */
  10
  11 /**
  12  ** balance_leaf_when_delete
  13  ** balance_leaf
  14  ** do_balance
  15  **
  16  **/
  17
  18 #include <asm/uaccess.h>
  19 #include <linux/time.h>
  20 #include <linux/reiserfs_fs.h>
  21 #include <linux/buffer_head.h>
  22 #include <linux/kernel.h>
  23
  24 #ifdef CONFIG_REISERFS_CHECK
  25
  26 struct tree_balance *cur_tb = NULL;     /* detects whether more than one
  27                                            copy of tb exists as a means
  28                                            of checking whether schedule
  29                                            is interrupting do_balance */
  30 #endif
  31
  32 inline void do_balance_mark_leaf_dirty(struct tree_balance *tb,
  33                                        struct buffer_head *bh, int flag)
  34 {
  35         journal_mark_dirty(tb->transaction_handle,
  36                            tb->transaction_handle->t_super, bh);
  37 }
  38
  39 #define do_balance_mark_internal_dirty do_balance_mark_leaf_dirty
  40 #define do_balance_mark_sb_dirty do_balance_mark_leaf_dirty
  41
  42 /* summary:
  43  if deleting something ( tb->insert_size[0] < 0 )
  44    return(balance_leaf_when_delete()); (flag d handled here)
  45  else
  46    if lnum is larger than 0 we put items into the left node
  47    if rnum is larger than 0 we put items into the right node
  48    if snum1 is larger than 0 we put items into the new node s1
  49    if snum2 is larger than 0 we put items into the new node s2
  50 Note that all *num* count new items being created.
  51
  52 It would be easier to read balance_leaf() if each of these summary
  53 lines was a separate procedure rather than being inlined.  I think
  54 that there are many passages here and in balance_leaf_when_delete() in
  55 which two calls to one procedure can replace two passages, and it
  56 might save cache space and improve software maintenance costs to do so.
  57
  58 Vladimir made the perceptive comment that we should offload most of
  59 the decision making in this function into fix_nodes/check_balance, and
  60 then create some sort of structure in tb that says what actions should
  61 be performed by do_balance.
  62
  63 -Hans */
  64
  65 /* Balance leaf node in case of delete or cut: insert_size[0] < 0
  66  *
  67  * lnum, rnum can have values >= -1
  68  *      -1 means that the neighbor must be joined with S
  69  *       0 means that nothing should be done with the neighbor
  70  *      >0 means to shift entirely or partly the specified number of items to the neighbor
  71  */
  72 static int balance_leaf_when_delete(struct tree_balance *tb, int flag)
  73 {
  74         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
  75         int item_pos = PATH_LAST_POSITION(tb->tb_path);
  76         int pos_in_item = tb->tb_path->pos_in_item;
  77         struct buffer_info bi;
  78         int n;
  79         struct item_head *ih;
  80
  81         RFALSE(tb->FR[0] && B_LEVEL(tb->FR[0]) != DISK_LEAF_NODE_LEVEL + 1,
  82                "vs- 12000: level: wrong FR %z", tb->FR[0]);
  83         RFALSE(tb->blknum[0] > 1,
  84                "PAP-12005: tb->blknum == %d, can not be > 1", tb->blknum[0]);
  85         RFALSE(!tb->blknum[0] && !PATH_H_PPARENT(tb->tb_path, 0),
  86                "PAP-12010: tree can not be empty");
  87
  88         ih = B_N_PITEM_HEAD(tbS0, item_pos);
  89
  90         /* Delete or truncate the item */
  91
  92         switch (flag) {
  93         case M_DELETE:          /* delete item in S[0] */
  94
  95                 RFALSE(ih_item_len(ih) + IH_SIZE != -tb->insert_size[0],
  96                        "vs-12013: mode Delete, insert size %d, ih to be deleted %h",
  97                        -tb->insert_size[0], ih);
  98
  99                 bi.tb = tb;
 100                 bi.bi_bh = tbS0;
 101                 bi.bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
 102                 bi.bi_position = PATH_H_POSITION(tb->tb_path, 1);
 103                 leaf_delete_items(&bi, 0, item_pos, 1, -1);
 104
 105                 if (!item_pos && tb->CFL[0]) {
 106                         if (B_NR_ITEMS(tbS0)) {
 107                                 replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0,
 108                                             0);
 109                         } else {
 110                                 if (!PATH_H_POSITION(tb->tb_path, 1))
 111                                         replace_key(tb, tb->CFL[0], tb->lkey[0],
 112                                                     PATH_H_PPARENT(tb->tb_path,
 113                                                                    0), 0);
 114                         }
 115                 }
 116
 117                 RFALSE(!item_pos && !tb->CFL[0],
 118                        "PAP-12020: tb->CFL[0]==%p, tb->L[0]==%p", tb->CFL[0],
 119                        tb->L[0]);
 120
 121                 break;
 122
 123         case M_CUT:{            /* cut item in S[0] */
 124                         bi.tb = tb;
 125                         bi.bi_bh = tbS0;
 126                         bi.bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
 127                         bi.bi_position = PATH_H_POSITION(tb->tb_path, 1);
 128                         if (is_direntry_le_ih(ih)) {
 129
 130                                 /* UFS unlink semantics are such that you can only delete one directory entry at a time. */
 131                                 /* when we cut a directory tb->insert_size[0] means number of entries to be cut (always 1) */
 132                                 tb->insert_size[0] = -1;
 133                                 leaf_cut_from_buffer(&bi, item_pos, pos_in_item,
 134                                                      -tb->insert_size[0]);
 135
 136                                 RFALSE(!item_pos && !pos_in_item && !tb->CFL[0],
 137                                        "PAP-12030: can not change delimiting key. CFL[0]=%p",
 138                                        tb->CFL[0]);
 139
 140                                 if (!item_pos && !pos_in_item && tb->CFL[0]) {
 141                                         replace_key(tb, tb->CFL[0], tb->lkey[0],
 142                                                     tbS0, 0);
 143                                 }
 144                         } else {
 145                                 leaf_cut_from_buffer(&bi, item_pos, pos_in_item,
 146                                                      -tb->insert_size[0]);
 147
 148                                 RFALSE(!ih_item_len(ih),
 149                                        "PAP-12035: cut must leave non-zero dynamic length of item");
 150                         }
 151                         break;
 152                 }
 153
 154         default:
 155                 print_cur_tb("12040");
 156                 reiserfs_panic(tb->tb_sb,
 157                                "PAP-12040: balance_leaf_when_delete: unexpectable mode: %s(%d)",
 158                                (flag ==
 159                                 M_PASTE) ? "PASTE" : ((flag ==
 160                                                        M_INSERT) ? "INSERT" :
 161                                                       "UNKNOWN"), flag);
 162         }
 163
 164         /* the rule is that no shifting occurs unless by shifting a node can be freed */
 165         n = B_NR_ITEMS(tbS0);
 166         if (tb->lnum[0]) {      /* L[0] takes part in balancing */
 167                 if (tb->lnum[0] == -1) {        /* L[0] must be joined with S[0] */
 168                         if (tb->rnum[0] == -1) {        /* R[0] must be also joined with S[0] */
 169                                 if (tb->FR[0] == PATH_H_PPARENT(tb->tb_path, 0)) {
 170                                         /* all contents of all the 3 buffers will be in L[0] */
 171                                         if (PATH_H_POSITION(tb->tb_path, 1) == 0
 172                                             && 1 < B_NR_ITEMS(tb->FR[0]))
 173                                                 replace_key(tb, tb->CFL[0],
 174                                                             tb->lkey[0],
 175                                                             tb->FR[0], 1);
 176
 177                                         leaf_move_items(LEAF_FROM_S_TO_L, tb, n,
 178                                                         -1, NULL);
 179                                         leaf_move_items(LEAF_FROM_R_TO_L, tb,
 180                                                         B_NR_ITEMS(tb->R[0]),
 181                                                         -1, NULL);
 182
 183                                         reiserfs_invalidate_buffer(tb, tbS0);
 184                                         reiserfs_invalidate_buffer(tb,
 185                                                                    tb->R[0]);
 186
 187                                         return 0;
 188                                 }
 189                                 /* all contents of all the 3 buffers will be in R[0] */
 190                                 leaf_move_items(LEAF_FROM_S_TO_R, tb, n, -1,
 191                                                 NULL);
 192                                 leaf_move_items(LEAF_FROM_L_TO_R, tb,
 193                                                 B_NR_ITEMS(tb->L[0]), -1, NULL);
 194
 195                                 /* right_delimiting_key is correct in R[0] */
 196                                 replace_key(tb, tb->CFR[0], tb->rkey[0],
 197                                             tb->R[0], 0);
 198
 199                                 reiserfs_invalidate_buffer(tb, tbS0);
 200                                 reiserfs_invalidate_buffer(tb, tb->L[0]);
 201
 202                                 return -1;
 203                         }
 204
 205                         RFALSE(tb->rnum[0] != 0,
 206                                "PAP-12045: rnum must be 0 (%d)", tb->rnum[0]);
 207                         /* all contents of L[0] and S[0] will be in L[0] */
 208                         leaf_shift_left(tb, n, -1);
 209
 210                         reiserfs_invalidate_buffer(tb, tbS0);
 211
 212                         return 0;
 213                 }
 214                 /* a part of contents of S[0] will be in L[0] and the rest part of S[0] will be in R[0] */
 215
 216                 RFALSE((tb->lnum[0] + tb->rnum[0] < n) ||
 217                        (tb->lnum[0] + tb->rnum[0] > n + 1),
 218                        "PAP-12050: rnum(%d) and lnum(%d) and item number(%d) in S[0] are not consistent",
 219                        tb->rnum[0], tb->lnum[0], n);
 220                 RFALSE((tb->lnum[0] + tb->rnum[0] == n) &&
 221                        (tb->lbytes != -1 || tb->rbytes != -1),
 222                        "PAP-12055: bad rbytes (%d)/lbytes (%d) parameters when items are not split",
 223                        tb->rbytes, tb->lbytes);
 224                 RFALSE((tb->lnum[0] + tb->rnum[0] == n + 1) &&
 225                        (tb->lbytes < 1 || tb->rbytes != -1),
 226                        "PAP-12060: bad rbytes (%d)/lbytes (%d) parameters when items are split",
 227                        tb->rbytes, tb->lbytes);
 228
 229                 leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
 230                 leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
 231
 232                 reiserfs_invalidate_buffer(tb, tbS0);
 233
 234                 return 0;
 235         }
 236
 237         if (tb->rnum[0] == -1) {
 238                 /* all contents of R[0] and S[0] will be in R[0] */
 239                 leaf_shift_right(tb, n, -1);
 240                 reiserfs_invalidate_buffer(tb, tbS0);
 241                 return 0;
 242         }
 243
 244         RFALSE(tb->rnum[0],
 245                "PAP-12065: bad rnum parameter must be 0 (%d)", tb->rnum[0]);
 246         return 0;
 247 }
 248
 249 static int balance_leaf(struct tree_balance *tb, struct item_head *ih,  /* item header of inserted item (this is on little endian) */
 250                         const char *body,       /* body  of inserted item or bytes to paste */
 251                         int flag,       /* i - insert, d - delete, c - cut, p - paste
 252                                            (see comment to do_balance) */
 253                         struct item_head *insert_key,   /* in our processing of one level we sometimes determine what
 254                                                            must be inserted into the next higher level.  This insertion
 255                                                            consists of a key or two keys and their corresponding
 256                                                            pointers */
 257                         struct buffer_head **insert_ptr /* inserted node-ptrs for the next level */
 258     )
 259 {
 260         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 261         int item_pos = PATH_LAST_POSITION(tb->tb_path); /*  index into the array of item headers in S[0]
 262                                                            of the affected item */
 263         struct buffer_info bi;
 264         struct buffer_head *S_new[2];   /* new nodes allocated to hold what could not fit into S */
 265         int snum[2];            /* number of items that will be placed
 266                                    into S_new (includes partially shifted
 267                                    items) */
 268         int sbytes[2];          /* if an item is partially shifted into S_new then
 269                                    if it is a directory item
 270                                    it is the number of entries from the item that are shifted into S_new
 271                                    else
 272                                    it is the number of bytes from the item that are shifted into S_new
 273                                  */
 274         int n, i;
 275         int ret_val;
 276         int pos_in_item;
 277         int zeros_num;
 278
 279         PROC_INFO_INC(tb->tb_sb, balance_at[0]);
 280
 281         /* Make balance in case insert_size[0] < 0 */
 282         if (tb->insert_size[0] < 0)
 283                 return balance_leaf_when_delete(tb, flag);
 284
 285         zeros_num = 0;
 286         if (flag == M_INSERT && !body)
 287                 zeros_num = ih_item_len(ih);
 288
 289         pos_in_item = tb->tb_path->pos_in_item;
 290         /* for indirect item pos_in_item is measured in unformatted node
 291            pointers. Recalculate to bytes */
 292         if (flag != M_INSERT
 293             && is_indirect_le_ih(B_N_PITEM_HEAD(tbS0, item_pos)))
 294                 pos_in_item *= UNFM_P_SIZE;
 295
 296         if (tb->lnum[0] > 0) {
 297                 /* Shift lnum[0] items from S[0] to the left neighbor L[0] */
 298                 if (item_pos < tb->lnum[0]) {
 299                         /* new item or it part falls to L[0], shift it too */
 300                         n = B_NR_ITEMS(tb->L[0]);
 301
 302                         switch (flag) {
 303                         case M_INSERT:  /* insert item into L[0] */
 304
 305                                 if (item_pos == tb->lnum[0] - 1
 306                                     && tb->lbytes != -1) {
 307                                         /* part of new item falls into L[0] */
 308                                         int new_item_len;
 309                                         int version;
 310
 311                                         ret_val =
 312                                             leaf_shift_left(tb, tb->lnum[0] - 1,
 313                                                             -1);
 314
 315                                         /* Calculate item length to insert to S[0] */
 316                                         new_item_len =
 317                                             ih_item_len(ih) - tb->lbytes;
 318                                         /* Calculate and check item length to insert to L[0] */
 319                                         put_ih_item_len(ih,
 320                                                         ih_item_len(ih) -
 321                                                         new_item_len);
 322
 323                                         RFALSE(ih_item_len(ih) <= 0,
 324                                                "PAP-12080: there is nothing to insert into L[0]: ih_item_len=%d",
 325                                                ih_item_len(ih));
 326
 327                                         /* Insert new item into L[0] */
 328                                         bi.tb = tb;
 329                                         bi.bi_bh = tb->L[0];
 330                                         bi.bi_parent = tb->FL[0];
 331                                         bi.bi_position =
 332                                             get_left_neighbor_position(tb, 0);
 333                                         leaf_insert_into_buf(&bi,
 334                                                              n + item_pos -
 335                                                              ret_val, ih, body,
 336                                                              zeros_num >
 337                                                              ih_item_len(ih) ?
 338                                                              ih_item_len(ih) :
 339                                                              zeros_num);
 340
 341                                         version = ih_version(ih);
 342
 343                                         /* Calculate key component, item length and body to insert into S[0] */
 344                                         set_le_ih_k_offset(ih,
 345                                                            le_ih_k_offset(ih) +
 346                                                            (tb->
 347                                                             lbytes <<
 348                                                             (is_indirect_le_ih
 349                                                              (ih) ? tb->tb_sb->
 350                                                              s_blocksize_bits -
 351                                                              UNFM_P_SHIFT :
 352                                                              0)));
 353
 354                                         put_ih_item_len(ih, new_item_len);
 355                                         if (tb->lbytes > zeros_num) {
 356                                                 body +=
 357                                                     (tb->lbytes - zeros_num);
 358                                                 zeros_num = 0;
 359                                         } else
 360                                                 zeros_num -= tb->lbytes;
 361
 362                                         RFALSE(ih_item_len(ih) <= 0,
 363                                                "PAP-12085: there is nothing to insert into S[0]: ih_item_len=%d",
 364                                                ih_item_len(ih));
 365                                 } else {
 366                                         /* new item in whole falls into L[0] */
 367                                         /* Shift lnum[0]-1 items to L[0] */
 368                                         ret_val =
 369                                             leaf_shift_left(tb, tb->lnum[0] - 1,
 370                                                             tb->lbytes);
 371                                         /* Insert new item into L[0] */
 372                                         bi.tb = tb;
 373                                         bi.bi_bh = tb->L[0];
 374                                         bi.bi_parent = tb->FL[0];
 375                                         bi.bi_position =
 376                                             get_left_neighbor_position(tb, 0);
 377                                         leaf_insert_into_buf(&bi,
 378                                                              n + item_pos -
 379                                                              ret_val, ih, body,
 380                                                              zeros_num);
 381                                         tb->insert_size[0] = 0;
 382                                         zeros_num = 0;
 383                                 }
 384                                 break;
 385
 386                         case M_PASTE:   /* append item in L[0] */
 387
 388                                 if (item_pos == tb->lnum[0] - 1
 389                                     && tb->lbytes != -1) {
 390                                         /* we must shift the part of the appended item */
 391                                         if (is_direntry_le_ih
 392                                             (B_N_PITEM_HEAD(tbS0, item_pos))) {
 393
 394                                                 RFALSE(zeros_num,
 395                                                        "PAP-12090: invalid parameter in case of a directory");
 396                                                 /* directory item */
 397                                                 if (tb->lbytes > pos_in_item) {
 398                                                         /* new directory entry falls into L[0] */
 399                                                         struct item_head
 400                                                             *pasted;
 401                                                         int l_pos_in_item =
 402                                                             pos_in_item;
 403
 404                                                         /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 entries from given directory item */
 405                                                         ret_val =
 406                                                             leaf_shift_left(tb,
 407                                                                             tb->
 408                                                                             lnum
 409                                                                             [0],
 410                                                                             tb->
 411                                                                             lbytes
 412                                                                             -
 413                                                                             1);
 414                                                         if (ret_val
 415                                                             && !item_pos) {
 416                                                                 pasted =
 417                                                                     B_N_PITEM_HEAD
 418                                                                     (tb->L[0],
 419                                                                      B_NR_ITEMS
 420                                                                      (tb->
 421                                                                       L[0]) -
 422                                                                      1);
 423                                                                 l_pos_in_item +=
 424                                                                     I_ENTRY_COUNT
 425                                                                     (pasted) -
 426                                                                     (tb->
 427                                                                      lbytes -
 428                                                                      1);
 429                                                         }
 430
 431                                                         /* Append given directory entry to directory item */
 432                                                         bi.tb = tb;
 433                                                         bi.bi_bh = tb->L[0];
 434                                                         bi.bi_parent =
 435                                                             tb->FL[0];
 436                                                         bi.bi_position =
 437                                                             get_left_neighbor_position
 438                                                             (tb, 0);
 439                                                         leaf_paste_in_buffer
 440                                                             (&bi,
 441                                                              n + item_pos -
 442                                                              ret_val,
 443                                                              l_pos_in_item,
 444                                                              tb->insert_size[0],
 445                                                              body, zeros_num);
 446
 447                                                         /* previous string prepared space for pasting new entry, following string pastes this entry */
 448
 449                                                         /* when we have merge directory item, pos_in_item has been changed too */
 450
 451                                                         /* paste new directory entry. 1 is entry number */
 452                                                         leaf_paste_entries(bi.
 453                                                                            bi_bh,
 454                                                                            n +
 455                                                                            item_pos
 456                                                                            -
 457                                                                            ret_val,
 458                                                                            l_pos_in_item,
 459                                                                            1,
 460                                                                            (struct
 461                                                                             reiserfs_de_head
 462                                                                             *)
 463                                                                            body,
 464                                                                            body
 465                                                                            +
 466                                                                            DEH_SIZE,
 467                                                                            tb->
 468                                                                            insert_size
 469                                                                            [0]
 470                                                             );
 471                                                         tb->insert_size[0] = 0;
 472                                                 } else {
 473                                                         /* new directory item doesn't fall into L[0] */
 474                                                         /* Shift lnum[0]-1 items in whole. Shift lbytes directory entries from directory item number lnum[0] */
 475                                                         leaf_shift_left(tb,
 476                                                                         tb->
 477                                                                         lnum[0],
 478                                                                         tb->
 479                                                                         lbytes);
 480                                                 }
 481                                                 /* Calculate new position to append in item body */
 482                                                 pos_in_item -= tb->lbytes;
 483                                         } else {
 484                                                 /* regular object */
 485                                                 RFALSE(tb->lbytes <= 0,
 486                                                        "PAP-12095: there is nothing to shift to L[0]. lbytes=%d",
 487                                                        tb->lbytes);
 488                                                 RFALSE(pos_in_item !=
 489                                                        ih_item_len
 490                                                        (B_N_PITEM_HEAD
 491                                                         (tbS0, item_pos)),
 492                                                        "PAP-12100: incorrect position to paste: item_len=%d, pos_in_item=%d",
 493                                                        ih_item_len
 494                                                        (B_N_PITEM_HEAD
 495                                                         (tbS0, item_pos)),
 496                                                        pos_in_item);
 497
 498                                                 if (tb->lbytes >= pos_in_item) {
 499                                                         /* appended item will be in L[0] in whole */
 500                                                         int l_n;
 501
 502                                                         /* this bytes number must be appended to the last item of L[h] */
 503                                                         l_n =
 504                                                             tb->lbytes -
 505                                                             pos_in_item;
 506
 507                                                         /* Calculate new insert_size[0] */
 508                                                         tb->insert_size[0] -=
 509                                                             l_n;
 510
 511                                                         RFALSE(tb->
 512                                                                insert_size[0] <=
 513                                                                0,
 514                                                                "PAP-12105: there is nothing to paste into L[0]. insert_size=%d",
 515                                                                tb->
 516                                                                insert_size[0]);
 517                                                         ret_val =
 518                                                             leaf_shift_left(tb,
 519                                                                             tb->
 520                                                                             lnum
 521                                                                             [0],
 522                                                                             ih_item_len
 523                                                                             (B_N_PITEM_HEAD
 524                                                                              (tbS0,
 525                                                                               item_pos)));
 526                                                         /* Append to body of item in L[0] */
 527                                                         bi.tb = tb;
 528                                                         bi.bi_bh = tb->L[0];
 529                                                         bi.bi_parent =
 530                                                             tb->FL[0];
 531                                                         bi.bi_position =
 532                                                             get_left_neighbor_position
 533                                                             (tb, 0);
 534                                                         leaf_paste_in_buffer
 535                                                             (&bi,
 536                                                              n + item_pos -
 537                                                              ret_val,
 538                                                              ih_item_len
 539                                                              (B_N_PITEM_HEAD
 540                                                               (tb->L[0],
 541                                                                n + item_pos -
 542                                                                ret_val)), l_n,
 543                                                              body,
 544                                                              zeros_num >
 545                                                              l_n ? l_n :
 546                                                              zeros_num);
 547                                                         /* 0-th item in S0 can be only of DIRECT type when l_n != 0 */
 548                                                         {
 549                                                                 int version;
 550                                                                 int temp_l =
 551                                                                     l_n;
 552
 553                                                                 RFALSE
 554                                                                     (ih_item_len
 555                                                                      (B_N_PITEM_HEAD
 556                                                                       (tbS0,
 557                                                                        0)),
 558                                                                      "PAP-12106: item length must be 0");
 559                                                                 RFALSE
 560                                                                     (comp_short_le_keys
 561                                                                      (B_N_PKEY
 562                                                                       (tbS0, 0),
 563                                                                       B_N_PKEY
 564                                                                       (tb->L[0],
 565                                                                        n +
 566                                                                        item_pos
 567                                                                        -
 568                                                                        ret_val)),
 569                                                                      "PAP-12107: items must be of the same file");
 570                                                                 if (is_indirect_le_ih(B_N_PITEM_HEAD(tb->L[0], n + item_pos - ret_val))) {
 571                                                                         temp_l =
 572                                                                             l_n
 573                                                                             <<
 574                                                                             (tb->
 575                                                                              tb_sb->
 576                                                                              s_blocksize_bits
 577                                                                              -
 578                                                                              UNFM_P_SHIFT);
 579                                                                 }
 580                                                                 /* update key of first item in S0 */
 581                                                                 version =
 582                                                                     ih_version
 583                                                                     (B_N_PITEM_HEAD
 584                                                                      (tbS0, 0));
 585                                                                 set_le_key_k_offset
 586                                                                     (version,
 587                                                                      B_N_PKEY
 588                                                                      (tbS0, 0),
 589                                                                      le_key_k_offset
 590                                                                      (version,
 591                                                                       B_N_PKEY
 592                                                                       (tbS0,
 593                                                                        0)) +
 594                                                                      temp_l);
 595                                                                 /* update left delimiting key */
 596                                                                 set_le_key_k_offset
 597                                                                     (version,
 598                                                                      B_N_PDELIM_KEY
 599                                                                      (tb->
 600                                                                       CFL[0],
 601                                                                       tb->
 602                                                                       lkey[0]),
 603                                                                      le_key_k_offset
 604                                                                      (version,
 605                                                                       B_N_PDELIM_KEY
 606                                                                       (tb->
 607                                                                        CFL[0],
 608                                                                        tb->
 609                                                                        lkey[0]))
 610                                                                      + temp_l);
 611                                                         }
 612
 613                                                         /* Calculate new body, position in item and insert_size[0] */
 614                                                         if (l_n > zeros_num) {
 615                                                                 body +=
 616                                                                     (l_n -
 617                                                                      zeros_num);
 618                                                                 zeros_num = 0;
 619                                                         } else
 620                                                                 zeros_num -=
 621                                                                     l_n;
 622                                                         pos_in_item = 0;
 623
 624                                                         RFALSE
 625                                                             (comp_short_le_keys
 626                                                              (B_N_PKEY(tbS0, 0),
 627                                                               B_N_PKEY(tb->L[0],
 628                                                                        B_NR_ITEMS
 629                                                                        (tb->
 630                                                                         L[0]) -
 631                                                                        1))
 632                                                              ||
 633                                                              !op_is_left_mergeable
 634                                                              (B_N_PKEY(tbS0, 0),
 635                                                               tbS0->b_size)
 636                                                              ||
 637                                                              !op_is_left_mergeable
 638                                                              (B_N_PDELIM_KEY
 639                                                               (tb->CFL[0],
 640                                                                tb->lkey[0]),
 641                                                               tbS0->b_size),
 642                                                              "PAP-12120: item must be merge-able with left neighboring item");
 643                                                 } else {        /* only part of the appended item will be in L[0] */
 644
 645                                                         /* Calculate position in item for append in S[0] */
 646                                                         pos_in_item -=
 647                                                             tb->lbytes;
 648
 649                                                         RFALSE(pos_in_item <= 0,
 650                                                                "PAP-12125: no place for paste. pos_in_item=%d",
 651                                                                pos_in_item);
 652
 653                                                         /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 byte from item number lnum[0] */
 654                                                         leaf_shift_left(tb,
 655                                                                         tb->
 656                                                                         lnum[0],
 657                                                                         tb->
 658                                                                         lbytes);
 659                                                 }
 660                                         }
 661                                 } else {        /* appended item will be in L[0] in whole */
 662
 663                                         struct item_head *pasted;
 664
 665                                         if (!item_pos && op_is_left_mergeable(B_N_PKEY(tbS0, 0), tbS0->b_size)) {       /* if we paste into first item of S[0] and it is left mergable */
 666                                                 /* then increment pos_in_item by the size of the last item in L[0] */
 667                                                 pasted =
 668                                                     B_N_PITEM_HEAD(tb->L[0],
 669                                                                    n - 1);
 670                                                 if (is_direntry_le_ih(pasted))
 671                                                         pos_in_item +=
 672                                                             ih_entry_count
 673                                                             (pasted);
 674                                                 else
 675                                                         pos_in_item +=
 676                                                             ih_item_len(pasted);
 677                                         }
 678
 679                                         /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 byte from item number lnum[0] */
 680                                         ret_val =
 681                                             leaf_shift_left(tb, tb->lnum[0],
 682                                                             tb->lbytes);
 683                                         /* Append to body of item in L[0] */
 684                                         bi.tb = tb;
 685                                         bi.bi_bh = tb->L[0];
 686                                         bi.bi_parent = tb->FL[0];
 687                                         bi.bi_position =
 688                                             get_left_neighbor_position(tb, 0);
 689                                         leaf_paste_in_buffer(&bi,
 690                                                              n + item_pos -
 691                                                              ret_val,
 692                                                              pos_in_item,
 693                                                              tb->insert_size[0],
 694                                                              body, zeros_num);
 695
 696                                         /* if appended item is directory, paste entry */
 697                                         pasted =
 698                                             B_N_PITEM_HEAD(tb->L[0],
 699                                                            n + item_pos -
 700                                                            ret_val);
 701                                         if (is_direntry_le_ih(pasted))
 702                                                 leaf_paste_entries(bi.bi_bh,
 703                                                                    n +
 704                                                                    item_pos -
 705                                                                    ret_val,
 706                                                                    pos_in_item,
 707                                                                    1,
 708                                                                    (struct
 709                                                                     reiserfs_de_head
 710                                                                     *)body,
 711                                                                    body +
 712                                                                    DEH_SIZE,
 713                                                                    tb->
 714                                                                    insert_size
 715                                                                    [0]
 716                                                     );
 717                                         /* if appended item is indirect item, put unformatted node into un list */
 718                                         if (is_indirect_le_ih(pasted))
 719                                                 set_ih_free_space(pasted, 0);
 720                                         tb->insert_size[0] = 0;
 721                                         zeros_num = 0;
 722                                 }
 723                                 break;
 724                         default:        /* cases d and t */
 725                                 reiserfs_panic(tb->tb_sb,
 726                                                "PAP-12130: balance_leaf: lnum > 0: unexpectable mode: %s(%d)",
 727                                                (flag ==
 728                                                 M_DELETE) ? "DELETE" : ((flag ==
 729                                                                          M_CUT)
 730                                                                         ? "CUT"
 731                                                                         :
 732                                                                         "UNKNOWN"),
 733                                                flag);
 734                         }
 735                 } else {
 736                         /* new item doesn't fall into L[0] */
 737                         leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
 738                 }
 739         }
 740
 741         /* tb->lnum[0] > 0 */
 742         /* Calculate new item position */
 743         item_pos -= (tb->lnum[0] - ((tb->lbytes != -1) ? 1 : 0));
 744
 745         if (tb->rnum[0] > 0) {
 746                 /* shift rnum[0] items from S[0] to the right neighbor R[0] */
 747                 n = B_NR_ITEMS(tbS0);
 748                 switch (flag) {
 749
 750                 case M_INSERT:  /* insert item */
 751                         if (n - tb->rnum[0] < item_pos) {       /* new item or its part falls to R[0] */
 752                                 if (item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1) {      /* part of new item falls into R[0] */
 753                                         loff_t old_key_comp, old_len,
 754                                             r_zeros_number;
 755                                         const char *r_body;
 756                                         int version;
 757                                         loff_t offset;
 758
 759                                         leaf_shift_right(tb, tb->rnum[0] - 1,
 760                                                          -1);
 761
 762                                         version = ih_version(ih);
 763                                         /* Remember key component and item length */
 764                                         old_key_comp = le_ih_k_offset(ih);
 765                                         old_len = ih_item_len(ih);
 766
 767                                         /* Calculate key component and item length to insert into R[0] */
 768                                         offset =
 769                                             le_ih_k_offset(ih) +
 770                                             ((old_len -
 771                                               tb->
 772                                               rbytes) << (is_indirect_le_ih(ih)
 773                                                           ? tb->tb_sb->
 774                                                           s_blocksize_bits -
 775                                                           UNFM_P_SHIFT : 0));
 776                                         set_le_ih_k_offset(ih, offset);
 777                                         put_ih_item_len(ih, tb->rbytes);
 778                                         /* Insert part of the item into R[0] */
 779                                         bi.tb = tb;
 780                                         bi.bi_bh = tb->R[0];
 781                                         bi.bi_parent = tb->FR[0];
 782                                         bi.bi_position =
 783                                             get_right_neighbor_position(tb, 0);
 784                                         if ((old_len - tb->rbytes) > zeros_num) {
 785                                                 r_zeros_number = 0;
 786                                                 r_body =
 787                                                     body + (old_len -
 788                                                             tb->rbytes) -
 789                                                     zeros_num;
 790                                         } else {
 791                                                 r_body = body;
 792                                                 r_zeros_number =
 793                                                     zeros_num - (old_len -
 794                                                                  tb->rbytes);
 795                                                 zeros_num -= r_zeros_number;
 796                                         }
 797
 798                                         leaf_insert_into_buf(&bi, 0, ih, r_body,
 799                                                              r_zeros_number);
 800
 801                                         /* Replace right delimiting key by first key in R[0] */
 802                                         replace_key(tb, tb->CFR[0], tb->rkey[0],
 803                                                     tb->R[0], 0);
 804
 805                                         /* Calculate key component and item length to insert into S[0] */
 806                                         set_le_ih_k_offset(ih, old_key_comp);
 807                                         put_ih_item_len(ih,
 808                                                         old_len - tb->rbytes);
 809
 810                                         tb->insert_size[0] -= tb->rbytes;
 811
 812                                 } else {        /* whole new item falls into R[0] */
 813
 814                                         /* Shift rnum[0]-1 items to R[0] */
 815                                         ret_val =
 816                                             leaf_shift_right(tb,
 817                                                              tb->rnum[0] - 1,
 818                                                              tb->rbytes);
 819                                         /* Insert new item into R[0] */
 820                                         bi.tb = tb;
 821                                         bi.bi_bh = tb->R[0];
 822                                         bi.bi_parent = tb->FR[0];
 823                                         bi.bi_position =
 824                                             get_right_neighbor_position(tb, 0);
 825                                         leaf_insert_into_buf(&bi,
 826                                                              item_pos - n +
 827                                                              tb->rnum[0] - 1,
 828                                                              ih, body,
 829                                                              zeros_num);
 830
 831                                         if (item_pos - n + tb->rnum[0] - 1 == 0) {
 832                                                 replace_key(tb, tb->CFR[0],
 833                                                             tb->rkey[0],
 834                                                             tb->R[0], 0);
 835
 836                                         }
 837                                         zeros_num = tb->insert_size[0] = 0;
 838                                 }
 839                         } else {        /* new item or part of it doesn't fall into R[0] */
 840
 841                                 leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
 842                         }
 843                         break;
 844
 845                 case M_PASTE:   /* append item */
 846
 847                         if (n - tb->rnum[0] <= item_pos) {      /* pasted item or part of it falls to R[0] */
 848                                 if (item_pos == n - tb->rnum[0] && tb->rbytes != -1) {  /* we must shift the part of the appended item */
 849                                         if (is_direntry_le_ih(B_N_PITEM_HEAD(tbS0, item_pos))) {        /* we append to directory item */
 850                                                 int entry_count;
 851
 852                                                 RFALSE(zeros_num,
 853                                                        "PAP-12145: invalid parameter in case of a directory");
 854                                                 entry_count =
 855                                                     I_ENTRY_COUNT(B_N_PITEM_HEAD
 856                                                                   (tbS0,
 857                                                                    item_pos));
 858                                                 if (entry_count - tb->rbytes <
 859                                                     pos_in_item)
 860                                                         /* new directory entry falls into R[0] */
 861                                                 {
 862                                                         int paste_entry_position;
 863
 864                                                         RFALSE(tb->rbytes - 1 >=
 865                                                                entry_count
 866                                                                || !tb->
 867                                                                insert_size[0],
 868                                                                "PAP-12150: no enough of entries to shift to R[0]: rbytes=%d, entry_count=%d",
 869                                                                tb->rbytes,
 870                                                                entry_count);
 871                                                         /* Shift rnum[0]-1 items in whole. Shift rbytes-1 directory entries from directory item number rnum[0] */
 872                                                         leaf_shift_right(tb,
 873                                                                          tb->
 874                                                                          rnum
 875                                                                          [0],
 876                                                                          tb->
 877                                                                          rbytes
 878                                                                          - 1);
 879                                                         /* Paste given directory entry to directory item */
 880                                                         paste_entry_position =
 881                                                             pos_in_item -
 882                                                             entry_count +
 883                                                             tb->rbytes - 1;
 884                                                         bi.tb = tb;
 885                                                         bi.bi_bh = tb->R[0];
 886                                                         bi.bi_parent =
 887                                                             tb->FR[0];
 888                                                         bi.bi_position =
 889                                                             get_right_neighbor_position
 890                                                             (tb, 0);
 891                                                         leaf_paste_in_buffer
 892                                                             (&bi, 0,
 893                                                              paste_entry_position,
 894                                                              tb->insert_size[0],
 895                                                              body, zeros_num);
 896                                                         /* paste entry */
 897                                                         leaf_paste_entries(bi.
 898                                                                            bi_bh,
 899                                                                            0,
 900                                                                            paste_entry_position,
 901                                                                            1,
 902                                                                            (struct
 903                                                                             reiserfs_de_head
 904                                                                             *)
 905                                                                            body,
 906                                                                            body
 907                                                                            +
 908                                                                            DEH_SIZE,
 909                                                                            tb->
 910                                                                            insert_size
 911                                                                            [0]
 912                                                             );
 913
 914                                                         if (paste_entry_position
 915                                                             == 0) {
 916                                                                 /* change delimiting keys */
 917                                                                 replace_key(tb,
 918                                                                             tb->
 919                                                                             CFR
 920                                                                             [0],
 921                                                                             tb->
 922                                                                             rkey
 923                                                                             [0],
 924                                                                             tb->
 925                                                                             R
 926                                                                             [0],
 927                                                                             0);
 928                                                         }
 929
 930                                                         tb->insert_size[0] = 0;
 931                                                         pos_in_item++;
 932                                                 } else {        /* new directory entry doesn't fall into R[0] */
 933
 934                                                         leaf_shift_right(tb,
 935                                                                          tb->
 936                                                                          rnum
 937                                                                          [0],
 938                                                                          tb->
 939                                                                          rbytes);
 940                                                 }
 941                                         } else {        /* regular object */
 942
 943                                                 int n_shift, n_rem,
 944                                                     r_zeros_number;
 945                                                 const char *r_body;
 946
 947                                                 /* Calculate number of bytes which must be shifted from appended item */
 948                                                 if ((n_shift =
 949                                                      tb->rbytes -
 950                                                      tb->insert_size[0]) < 0)
 951                                                         n_shift = 0;
 952
 953                                                 RFALSE(pos_in_item !=
 954                                                        ih_item_len
 955                                                        (B_N_PITEM_HEAD
 956                                                         (tbS0, item_pos)),
 957                                                        "PAP-12155: invalid position to paste. ih_item_len=%d, pos_in_item=%d",
 958                                                        pos_in_item,
 959                                                        ih_item_len
 960                                                        (B_N_PITEM_HEAD
 961                                                         (tbS0, item_pos)));
 962
 963                                                 leaf_shift_right(tb,
 964                                                                  tb->rnum[0],
 965                                                                  n_shift);
 966                                                 /* Calculate number of bytes which must remain in body after appending to R[0] */
 967                                                 if ((n_rem =
 968                                                      tb->insert_size[0] -
 969                                                      tb->rbytes) < 0)
 970                                                         n_rem = 0;
 971
 972                                                 {
 973                                                         int version;
 974                                                         unsigned long temp_rem =
 975                                                             n_rem;
 976
 977                                                         version =
 978                                                             ih_version
 979                                                             (B_N_PITEM_HEAD
 980                                                              (tb->R[0], 0));
 981                                                         if (is_indirect_le_key
 982                                                             (version,
 983                                                              B_N_PKEY(tb->R[0],
 984                                                                       0))) {
 985                                                                 temp_rem =
 986                                                                     n_rem <<
 987                                                                     (tb->tb_sb->
 988                                                                      s_blocksize_bits
 989                                                                      -
 990                                                                      UNFM_P_SHIFT);
 991                                                         }
 992                                                         set_le_key_k_offset
 993                                                             (version,
 994                                                              B_N_PKEY(tb->R[0],
 995                                                                       0),
 996                                                              le_key_k_offset
 997                                                              (version,
 998                                                               B_N_PKEY(tb->R[0],
 999                                                                        0)) +
1000                                                              temp_rem);
1001                                                         set_le_key_k_offset
1002                                                             (version,
1003                                                              B_N_PDELIM_KEY(tb->
1004                                                                             CFR
1005                                                                             [0],
1006                                                                             tb->
1007                                                                             rkey
1008                                                                             [0]),
1009                                                              le_key_k_offset
1010                                                              (version,
1011                                                               B_N_PDELIM_KEY
1012                                                               (tb->CFR[0],
1013                                                                tb->rkey[0])) +
1014                                                              temp_rem);
1015                                                 }
1016 /*                k_offset (B_N_PKEY(tb->R[0],0)) += n_rem;
1017                   k_offset (B_N_PDELIM_KEY(tb->CFR[0],tb->rkey[0])) += n_rem;*/
1018                                                 do_balance_mark_internal_dirty
1019                                                     (tb, tb->CFR[0], 0);
1020
1021                                                 /* Append part of body into R[0] */
1022                                                 bi.tb = tb;
1023                                                 bi.bi_bh = tb->R[0];
1024                                                 bi.bi_parent = tb->FR[0];
1025                                                 bi.bi_position =
1026                                                     get_right_neighbor_position
1027                                                     (tb, 0);
1028                                                 if (n_rem > zeros_num) {
1029                                                         r_zeros_number = 0;
1030                                                         r_body =
1031                                                             body + n_rem -
1032                                                             zeros_num;
1033                                                 } else {
1034                                                         r_body = body;
1035                                                         r_zeros_number =
1036                                                             zeros_num - n_rem;
1037                                                         zeros_num -=
1038                                                             r_zeros_number;
1039                                                 }
1040
1041                                                 leaf_paste_in_buffer(&bi, 0,
1042                                                                      n_shift,
1043                                                                      tb->
1044                                                                      insert_size
1045                                                                      [0] -
1046                                                                      n_rem,
1047                                                                      r_body,
1048                                                                      r_zeros_number);
1049
1050                                                 if (is_indirect_le_ih
1051                                                     (B_N_PITEM_HEAD
1052                                                      (tb->R[0], 0))) {
1053 #if 0
1054                                                         RFALSE(n_rem,
1055                                                                "PAP-12160: paste more than one unformatted node pointer");
1056 #endif
1057                                                         set_ih_free_space
1058                                                             (B_N_PITEM_HEAD
1059                                                              (tb->R[0], 0), 0);
1060                                                 }
1061                                                 tb->insert_size[0] = n_rem;
1062                                                 if (!n_rem)
1063                                                         pos_in_item++;
1064                                         }
1065                                 } else {        /* pasted item in whole falls into R[0] */
1066
1067                                         struct item_head *pasted;
1068
1069                                         ret_val =
1070                                             leaf_shift_right(tb, tb->rnum[0],
1071                                                              tb->rbytes);
1072                                         /* append item in R[0] */
1073                                         if (pos_in_item >= 0) {
1074                                                 bi.tb = tb;
1075                                                 bi.bi_bh = tb->R[0];
1076                                                 bi.bi_parent = tb->FR[0];
1077                                                 bi.bi_position =
1078                                                     get_right_neighbor_position
1079                                                     (tb, 0);
1080                                                 leaf_paste_in_buffer(&bi,
1081                                                                      item_pos -
1082                                                                      n +
1083                                                                      tb->
1084                                                                      rnum[0],
1085                                                                      pos_in_item,
1086                                                                      tb->
1087                                                                      insert_size
1088                                                                      [0], body,
1089                                                                      zeros_num);
1090                                         }
1091
1092                                         /* paste new entry, if item is directory item */
1093                                         pasted =
1094                                             B_N_PITEM_HEAD(tb->R[0],
1095                                                            item_pos - n +
1096                                                            tb->rnum[0]);
1097                                         if (is_direntry_le_ih(pasted)
1098                                             && pos_in_item >= 0) {
1099                                                 leaf_paste_entries(bi.bi_bh,
1100                                                                    item_pos -
1101                                                                    n +
1102                                                                    tb->rnum[0],
1103                                                                    pos_in_item,
1104                                                                    1,
1105                                                                    (struct
1106                                                                     reiserfs_de_head
1107                                                                     *)body,
1108                                                                    body +
1109                                                                    DEH_SIZE,
1110                                                                    tb->
1111                                                                    insert_size
1112                                                                    [0]
1113                                                     );
1114                                                 if (!pos_in_item) {
1115
1116                                                         RFALSE(item_pos - n +
1117                                                                tb->rnum[0],
1118                                                                "PAP-12165: directory item must be first item of node when pasting is in 0th position");
1119
1120                                                         /* update delimiting keys */
1121                                                         replace_key(tb,
1122                                                                     tb->CFR[0],
1123                                                                     tb->rkey[0],
1124                                                                     tb->R[0],
1125                                                                     0);
1126                                                 }
1127                                         }
1128
1129                                         if (is_indirect_le_ih(pasted))
1130                                                 set_ih_free_space(pasted, 0);
1131                                         zeros_num = tb->insert_size[0] = 0;
1132                                 }
1133                         } else {        /* new item doesn't fall into R[0] */
1134
1135                                 leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
1136                         }
1137                         break;
1138                 default:        /* cases d and t */
1139                         reiserfs_panic(tb->tb_sb,
1140                                        "PAP-12175: balance_leaf: rnum > 0: unexpectable mode: %s(%d)",
1141                                        (flag ==
1142                                         M_DELETE) ? "DELETE" : ((flag ==
1143                                                                  M_CUT) ? "CUT"
1144                                                                 : "UNKNOWN"),
1145                                        flag);
1146                 }
1147
1148         }
1149
1150         /* tb->rnum[0] > 0 */
1151         RFALSE(tb->blknum[0] > 3,
1152                "PAP-12180: blknum can not be %d. It must be <= 3",
1153                tb->blknum[0]);
1154         RFALSE(tb->blknum[0] < 0,
1155                "PAP-12185: blknum can not be %d. It must be >= 0",
1156                tb->blknum[0]);
1157
1158         /* if while adding to a node we discover that it is possible to split
1159            it in two, and merge the left part into the left neighbor and the
1160            right part into the right neighbor, eliminating the node */
1161         if (tb->blknum[0] == 0) {       /* node S[0] is empty now */
1162
1163                 RFALSE(!tb->lnum[0] || !tb->rnum[0],
1164                        "PAP-12190: lnum and rnum must not be zero");
1165                 /* if insertion was done before 0-th position in R[0], right
1166                    delimiting key of the tb->L[0]'s and left delimiting key are
1167                    not set correctly */
1168                 if (tb->CFL[0]) {
1169                         if (!tb->CFR[0])
1170                                 reiserfs_panic(tb->tb_sb,
1171                                                "vs-12195: balance_leaf: CFR not initialized");
1172                         copy_key(B_N_PDELIM_KEY(tb->CFL[0], tb->lkey[0]),
1173                                  B_N_PDELIM_KEY(tb->CFR[0], tb->rkey[0]));
1174                         do_balance_mark_internal_dirty(tb, tb->CFL[0], 0);
1175                 }
1176
1177                 reiserfs_invalidate_buffer(tb, tbS0);
1178                 return 0;
1179         }
1180
1181         /* Fill new nodes that appear in place of S[0] */
1182
1183         /* I am told that this copying is because we need an array to enable
1184            the looping code. -Hans */
1185         snum[0] = tb->s1num, snum[1] = tb->s2num;
1186         sbytes[0] = tb->s1bytes;
1187         sbytes[1] = tb->s2bytes;
1188         for (i = tb->blknum[0] - 2; i >= 0; i--) {
1189
1190                 RFALSE(!snum[i], "PAP-12200: snum[%d] == %d. Must be > 0", i,
1191                        snum[i]);
1192
1193                 /* here we shift from S to S_new nodes */
1194
1195                 S_new[i] = get_FEB(tb);
1196
1197                 /* initialized block type and tree level */
1198                 set_blkh_level(B_BLK_HEAD(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
1205                         if (n - snum[i] < item_pos) {   /* new item or it's part falls to first new node S_new[i] */
1206                                 if (item_pos == n - snum[i] + 1 && sbytes[i] != -1) {   /* part of new item falls into S_new[i] */
1207                                         int old_key_comp, old_len,
1208                                             r_zeros_number;
1209                                         const char *r_body;
1210                                         int version;
1211
1212                                         /* Move snum[i]-1 items from S[0] to S_new[i] */
1213                                         leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
1214                                                         snum[i] - 1, -1,
1215                                                         S_new[i]);
1216                                         /* Remember key component and item length */
1217                                         version = ih_version(ih);
1218                                         old_key_comp = le_ih_k_offset(ih);
1219                                         old_len = ih_item_len(ih);
1220
1221                                         /* Calculate key component and item length to insert into S_new[i] */
1222                                         set_le_ih_k_offset(ih,
1223                                                            le_ih_k_offset(ih) +
1224                                                            ((old_len -
1225                                                              sbytes[i]) <<
1226                                                             (is_indirect_le_ih
1227                                                              (ih) ? tb->tb_sb->
1228                                                              s_blocksize_bits -
1229                                                              UNFM_P_SHIFT :
1230                                                              0)));
1231
1232                                         put_ih_item_len(ih, sbytes[i]);
1233
1234                                         /* Insert part of the item into S_new[i] before 0-th item */
1235                                         bi.tb = tb;
1236                                         bi.bi_bh = S_new[i];
1237                                         bi.bi_parent = NULL;
1238                                         bi.bi_position = 0;
1239
1240                                         if ((old_len - sbytes[i]) > zeros_num) {
1241                                                 r_zeros_number = 0;
1242                                                 r_body =
1243                                                     body + (old_len -
1244                                                             sbytes[i]) -
1245                                                     zeros_num;
1246                                         } else {
1247                                                 r_body = body;
1248                                                 r_zeros_number =
1249                                                     zeros_num - (old_len -
1250                                                                  sbytes[i]);
1251                                                 zeros_num -= r_zeros_number;
1252                                         }
1253
1254                                         leaf_insert_into_buf(&bi, 0, ih, r_body,
1255                                                              r_zeros_number);
1256
1257                                         /* Calculate key component and item length to insert into S[i] */
1258                                         set_le_ih_k_offset(ih, old_key_comp);
1259                                         put_ih_item_len(ih,
1260                                                         old_len - sbytes[i]);
1261                                         tb->insert_size[0] -= sbytes[i];
1262                                 } else {        /* whole new item falls into S_new[i] */
1263
1264                                         /* Shift snum[0] - 1 items to S_new[i] (sbytes[i] of split item) */
1265                                         leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
1266                                                         snum[i] - 1, sbytes[i],
1267                                                         S_new[i]);
1268
1269                                         /* Insert new item into S_new[i] */
1270                                         bi.tb = tb;
1271                                         bi.bi_bh = S_new[i];
1272                                         bi.bi_parent = NULL;
1273                                         bi.bi_position = 0;
1274                                         leaf_insert_into_buf(&bi,
1275                                                              item_pos - n +
1276                                                              snum[i] - 1, ih,
1277                                                              body, zeros_num);
1278
1279                                         zeros_num = tb->insert_size[0] = 0;
1280                                 }
1281                         }
1282
1283                         else {  /* new item or it part don't falls into S_new[i] */
1284
1285                                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
1286                                                 snum[i], sbytes[i], S_new[i]);
1287                         }
1288                         break;
1289
1290                 case M_PASTE:   /* append item */
1291
1292                         if (n - snum[i] <= item_pos) {  /* pasted item or part if it falls to S_new[i] */
1293                                 if (item_pos == n - snum[i] && sbytes[i] != -1) {       /* we must shift part of the appended item */
1294                                         struct item_head *aux_ih;
1295
1296                                         RFALSE(ih, "PAP-12210: ih must be 0");
1297
1298                                         if (is_direntry_le_ih
1299                                             (aux_ih =
1300                                              B_N_PITEM_HEAD(tbS0, item_pos))) {
1301                                                 /* we append to directory item */
1302
1303                                                 int entry_count;
1304
1305                                                 entry_count =
1306                                                     ih_entry_count(aux_ih);
1307
1308                                                 if (entry_count - sbytes[i] <
1309                                                     pos_in_item
1310                                                     && pos_in_item <=
1311                                                     entry_count) {
1312                                                         /* new directory entry falls into S_new[i] */
1313
1314                                                         RFALSE(!tb->
1315                                                                insert_size[0],
1316                                                                "PAP-12215: insert_size is already 0");
1317                                                         RFALSE(sbytes[i] - 1 >=
1318                                                                entry_count,
1319                                                                "PAP-12220: there are no so much entries (%d), only %d",
1320                                                                sbytes[i] - 1,
1321                                                                entry_count);
1322
1323                                                         /* Shift snum[i]-1 items in whole. Shift sbytes[i] directory entries from directory item number snum[i] */
1324                                                         leaf_move_items
1325                                                             (LEAF_FROM_S_TO_SNEW,
1326                                                              tb, snum[i],
1327                                                              sbytes[i] - 1,
1328                                                              S_new[i]);
1329                                                         /* Paste given directory entry to directory item */
1330                                                         bi.tb = tb;
1331                                                         bi.bi_bh = S_new[i];
1332                                                         bi.bi_parent = NULL;
1333                                                         bi.bi_position = 0;
1334                                                         leaf_paste_in_buffer
1335                                                             (&bi, 0,
1336                                                              pos_in_item -
1337                                                              entry_count +
1338                                                              sbytes[i] - 1,
1339                                                              tb->insert_size[0],
1340                                                              body, zeros_num);
1341                                                         /* paste new directory entry */
1342                                                         leaf_paste_entries(bi.
1343                                                                            bi_bh,
1344                                                                            0,
1345                                                                            pos_in_item
1346                                                                            -
1347                                                                            entry_count
1348                                                                            +
1349                                                                            sbytes
1350                                                                            [i] -
1351                                                                            1, 1,
1352                                                                            (struct
1353                                                                             reiserfs_de_head
1354                                                                             *)
1355                                                                            body,
1356                                                                            body
1357                                                                            +
1358                                                                            DEH_SIZE,
1359                                                                            tb->
1360                                                                            insert_size
1361                                                                            [0]
1362                                                             );
1363                                                         tb->insert_size[0] = 0;
1364                                                         pos_in_item++;
1365                                                 } else {        /* new directory entry doesn't fall into S_new[i] */
1366                                                         leaf_move_items
1367                                                             (LEAF_FROM_S_TO_SNEW,
1368                                                              tb, snum[i],
1369                                                              sbytes[i],
1370                                                              S_new[i]);
1371                                                 }
1372                                         } else {        /* regular object */
1373
1374                                                 int n_shift, n_rem,
1375                                                     r_zeros_number;
1376                                                 const char *r_body;
1377
1378                                                 RFALSE(pos_in_item !=
1379                                                        ih_item_len
1380                                                        (B_N_PITEM_HEAD
1381                                                         (tbS0, item_pos))
1382                                                        || tb->insert_size[0] <=
1383                                                        0,
1384                                                        "PAP-12225: item too short or insert_size <= 0");
1385
1386                                                 /* Calculate number of bytes which must be shifted from appended item */
1387                                                 n_shift =
1388                                                     sbytes[i] -
1389                                                     tb->insert_size[0];
1390                                                 if (n_shift < 0)
1391                                                         n_shift = 0;
1392                                                 leaf_move_items
1393                                                     (LEAF_FROM_S_TO_SNEW, tb,
1394                                                      snum[i], n_shift,
1395                                                      S_new[i]);
1396
1397                                                 /* Calculate number of bytes which must remain in body after append to S_new[i] */
1398                                                 n_rem =
1399                                                     tb->insert_size[0] -
1400                                                     sbytes[i];
1401                                                 if (n_rem < 0)
1402                                                         n_rem = 0;
1403                                                 /* Append part of body into S_new[0] */
1404                                                 bi.tb = tb;
1405                                                 bi.bi_bh = S_new[i];
1406                                                 bi.bi_parent = NULL;
1407                                                 bi.bi_position = 0;
1408
1409                                                 if (n_rem > zeros_num) {
1410                                                         r_zeros_number = 0;
1411                                                         r_body =
1412                                                             body + n_rem -
1413                                                             zeros_num;
1414                                                 } else {
1415                                                         r_body = body;
1416                                                         r_zeros_number =
1417                                                             zeros_num - n_rem;
1418                                                         zeros_num -=
1419                                                             r_zeros_number;
1420                                                 }
1421
1422                                                 leaf_paste_in_buffer(&bi, 0,
1423                                                                      n_shift,
1424                                                                      tb->
1425                                                                      insert_size
1426                                                                      [0] -
1427                                                                      n_rem,
1428                                                                      r_body,
1429                                                                      r_zeros_number);
1430                                                 {
1431                                                         struct item_head *tmp;
1432
1433                                                         tmp =
1434                                                             B_N_PITEM_HEAD(S_new
1435                                                                            [i],
1436                                                                            0);
1437                                                         if (is_indirect_le_ih
1438                                                             (tmp)) {
1439                                                                 set_ih_free_space
1440                                                                     (tmp, 0);
1441                                                                 set_le_ih_k_offset
1442                                                                     (tmp,
1443                                                                      le_ih_k_offset
1444                                                                      (tmp) +
1445                                                                      (n_rem <<
1446                                                                       (tb->
1447                                                                        tb_sb->
1448                                                                        s_blocksize_bits
1449                                                                        -
1450                                                                        UNFM_P_SHIFT)));
1451                                                         } else {
1452                                                                 set_le_ih_k_offset
1453                                                                     (tmp,
1454                                                                      le_ih_k_offset
1455                                                                      (tmp) +
1456                                                                      n_rem);
1457                                                         }
1458                                                 }
1459
1460                                                 tb->insert_size[0] = n_rem;
1461                                                 if (!n_rem)
1462                                                         pos_in_item++;
1463                                         }
1464                                 } else
1465                                         /* item falls wholly into S_new[i] */
1466                                 {
1467                                         int ret_val;
1468                                         struct item_head *pasted;
1469
1470 #ifdef CONFIG_REISERFS_CHECK
1471                                         struct item_head *ih =
1472                                             B_N_PITEM_HEAD(tbS0, item_pos);
1473
1474                                         if (!is_direntry_le_ih(ih)
1475                                             && (pos_in_item != ih_item_len(ih)
1476                                                 || tb->insert_size[0] <= 0))
1477                                                 reiserfs_panic(tb->tb_sb,
1478                                                                "PAP-12235: balance_leaf: pos_in_item must be equal to ih_item_len");
1479 #endif                          /* CONFIG_REISERFS_CHECK */
1480
1481                                         ret_val =
1482                                             leaf_move_items(LEAF_FROM_S_TO_SNEW,
1483                                                             tb, snum[i],
1484                                                             sbytes[i],
1485                                                             S_new[i]);
1486
1487                                         RFALSE(ret_val,
1488                                                "PAP-12240: unexpected value returned by leaf_move_items (%d)",
1489                                                ret_val);
1490
1491                                         /* paste into item */
1492                                         bi.tb = tb;
1493                                         bi.bi_bh = S_new[i];
1494                                         bi.bi_parent = NULL;
1495                                         bi.bi_position = 0;
1496                                         leaf_paste_in_buffer(&bi,
1497                                                              item_pos - n +
1498                                                              snum[i],
1499                                                              pos_in_item,
1500                                                              tb->insert_size[0],
1501                                                              body, zeros_num);
1502
1503                                         pasted =
1504                                             B_N_PITEM_HEAD(S_new[i],
1505                                                            item_pos - n +
1506                                                            snum[i]);
1507                                         if (is_direntry_le_ih(pasted)) {
1508                                                 leaf_paste_entries(bi.bi_bh,
1509                                                                    item_pos -
1510                                                                    n + snum[i],
1511                                                                    pos_in_item,
1512                                                                    1,
1513                                                                    (struct
1514                                                                     reiserfs_de_head
1515                                                                     *)body,
1516                                                                    body +
1517                                                                    DEH_SIZE,
1518                                                                    tb->
1519                                                                    insert_size
1520                                                                    [0]
1521                                                     );
1522                                         }
1523
1524                                         /* if we paste to indirect item update ih_free_space */
1525                                         if (is_indirect_le_ih(pasted))
1526                                                 set_ih_free_space(pasted, 0);
1527                                         zeros_num = tb->insert_size[0] = 0;
1528                                 }
1529                         }
1530
1531                         else {  /* pasted item doesn't fall into S_new[i] */
1532
1533                                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
1534                                                 snum[i], sbytes[i], S_new[i]);
1535                         }
1536                         break;
1537                 default:        /* cases d and t */
1538                         reiserfs_panic(tb->tb_sb,
1539                                        "PAP-12245: balance_leaf: blknum > 2: unexpectable mode: %s(%d)",
1540                                        (flag ==
1541                                         M_DELETE) ? "DELETE" : ((flag ==
1542                                                                  M_CUT) ? "CUT"
1543                                                                 : "UNKNOWN"),
1544                                        flag);
1545                 }
1546
1547                 memcpy(insert_key + i, B_N_PKEY(S_new[i], 0), KEY_SIZE);
1548                 insert_ptr[i] = S_new[i];
1549
1550                 RFALSE(!buffer_journaled(S_new[i])
1551                        || buffer_journal_dirty(S_new[i])
1552                        || buffer_dirty(S_new[i]), "PAP-12247: S_new[%d] : (%b)",
1553                        i, S_new[i]);
1554         }
1555
1556         /* if the affected item was not wholly shifted then we perform all necessary operations on that part or whole of the
1557            affected item which remains in S */
1558         if (0 <= item_pos && item_pos < tb->s0num) {    /* if we must insert or append into buffer S[0] */
1559
1560                 switch (flag) {
1561                 case M_INSERT:  /* insert item into S[0] */
1562                         bi.tb = tb;
1563                         bi.bi_bh = tbS0;
1564                         bi.bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
1565                         bi.bi_position = PATH_H_POSITION(tb->tb_path, 1);
1566                         leaf_insert_into_buf(&bi, item_pos, ih, body,
1567                                              zeros_num);
1568
1569                         /* If we insert the first key change the delimiting key */
1570                         if (item_pos == 0) {
1571                                 if (tb->CFL[0]) /* can be 0 in reiserfsck */
1572                                         replace_key(tb, tb->CFL[0], tb->lkey[0],
1573                                                     tbS0, 0);
1574
1575                         }
1576                         break;
1577
1578                 case M_PASTE:{  /* append item in S[0] */
1579                                 struct item_head *pasted;
1580
1581                                 pasted = B_N_PITEM_HEAD(tbS0, item_pos);
1582                                 /* when directory, may be new entry already pasted */
1583                                 if (is_direntry_le_ih(pasted)) {
1584                                         if (pos_in_item >= 0 &&
1585                                             pos_in_item <=
1586                                             ih_entry_count(pasted)) {
1587
1588                                                 RFALSE(!tb->insert_size[0],
1589                                                        "PAP-12260: insert_size is 0 already");
1590
1591                                                 /* prepare space */
1592                                                 bi.tb = tb;
1593                                                 bi.bi_bh = tbS0;
1594                                                 bi.bi_parent =
1595                                                     PATH_H_PPARENT(tb->tb_path,
1596                                                                    0);
1597                                                 bi.bi_position =
1598                                                     PATH_H_POSITION(tb->tb_path,
1599                                                                     1);
1600                                                 leaf_paste_in_buffer(&bi,
1601                                                                      item_pos,
1602                                                                      pos_in_item,
1603                                                                      tb->
1604                                                                      insert_size
1605                                                                      [0], body,
1606                                                                      zeros_num);
1607
1608                                                 /* paste entry */
1609                                                 leaf_paste_entries(bi.bi_bh,
1610                                                                    item_pos,
1611                                                                    pos_in_item,
1612                                                                    1,
1613                                                                    (struct
1614                                                                     reiserfs_de_head
1615                                                                     *)body,
1616                                                                    body +
1617                                                                    DEH_SIZE,
1618                                                                    tb->
1619                                                                    insert_size
1620                                                                    [0]
1621                                                     );
1622                                                 if (!item_pos && !pos_in_item) {
1623                                                         RFALSE(!tb->CFL[0]
1624                                                                || !tb->L[0],
1625                                                                "PAP-12270: CFL[0]/L[0] must be specified");
1626                                                         if (tb->CFL[0]) {
1627                                                                 replace_key(tb,
1628                                                                             tb->
1629                                                                             CFL
1630                                                                             [0],
1631                                                                             tb->
1632                                                                             lkey
1633                                                                             [0],
1634                                                                             tbS0,
1635                                                                             0);
1636
1637                                                         }
1638                                                 }
1639                                                 tb->insert_size[0] = 0;
1640                                         }
1641                                 } else {        /* regular object */
1642                                         if (pos_in_item == ih_item_len(pasted)) {
1643
1644                                                 RFALSE(tb->insert_size[0] <= 0,
1645                                                        "PAP-12275: insert size must not be %d",
1646                                                        tb->insert_size[0]);
1647                                                 bi.tb = tb;
1648                                                 bi.bi_bh = tbS0;
1649                                                 bi.bi_parent =
1650                                                     PATH_H_PPARENT(tb->tb_path,
1651                                                                    0);
1652                                                 bi.bi_position =
1653                                                     PATH_H_POSITION(tb->tb_path,
1654                                                                     1);
1655                                                 leaf_paste_in_buffer(&bi,
1656                                                                      item_pos,
1657                                                                      pos_in_item,
1658                                                                      tb->
1659                                                                      insert_size
1660                                                                      [0], body,
1661                                                                      zeros_num);
1662
1663                                                 if (is_indirect_le_ih(pasted)) {
1664 #if 0
1665                                                         RFALSE(tb->
1666                                                                insert_size[0] !=
1667                                                                UNFM_P_SIZE,
1668                                                                "PAP-12280: insert_size for indirect item must be %d, not %d",
1669                                                                UNFM_P_SIZE,
1670                                                                tb->
1671                                                                insert_size[0]);
1672 #endif
1673                                                         set_ih_free_space
1674                                                             (pasted, 0);
1675                                                 }
1676                                                 tb->insert_size[0] = 0;
1677                                         }
1678 #ifdef CONFIG_REISERFS_CHECK
1679                                         else {
1680                                                 if (tb->insert_size[0]) {
1681                                                         print_cur_tb("12285");
1682                                                         reiserfs_panic(tb->
1683                                                                        tb_sb,
1684                                                                        "PAP-12285: balance_leaf: insert_size must be 0 (%d)",
1685                                                                        tb->
1686                                                                        insert_size
1687                                                                        [0]);
1688                                                 }
1689                                         }
1690 #endif                          /* CONFIG_REISERFS_CHECK */
1691
1692                                 }
1693                         }       /* case M_PASTE: */
1694                 }
1695         }
1696 #ifdef CONFIG_REISERFS_CHECK
1697         if (flag == M_PASTE && tb->insert_size[0]) {
1698                 print_cur_tb("12290");
1699                 reiserfs_panic(tb->tb_sb,
1700                                "PAP-12290: balance_leaf: insert_size is still not 0 (%d)",
1701                                tb->insert_size[0]);
1702         }
1703 #endif                          /* CONFIG_REISERFS_CHECK */
1704
1705         return 0;
1706 }                               /* Leaf level of the tree is balanced (end of balance_leaf) */
1707
1708 /* Make empty node */
1709 void make_empty_node(struct buffer_info *bi)
1710 {
1711         struct block_head *blkh;
1712
1713         RFALSE(bi->bi_bh == NULL, "PAP-12295: pointer to the buffer is NULL");
1714
1715         blkh = B_BLK_HEAD(bi->bi_bh);
1716         set_blkh_nr_item(blkh, 0);
1717         set_blkh_free_space(blkh, MAX_CHILD_SIZE(bi->bi_bh));
1718
1719         if (bi->bi_parent)
1720                 B_N_CHILD(bi->bi_parent, bi->bi_position)->dc_size = 0; /* Endian safe if 0 */
1721 }
1722
1723 /* Get first empty buffer */
1724 struct buffer_head *get_FEB(struct tree_balance *tb)
1725 {
1726         int i;
1727         struct buffer_head *first_b;
1728         struct buffer_info bi;
1729
1730         for (i = 0; i < MAX_FEB_SIZE; i++)
1731                 if (tb->FEB[i] != NULL)
1732                         break;
1733
1734         if (i == MAX_FEB_SIZE)
1735                 reiserfs_panic(tb->tb_sb,
1736                                "vs-12300: get_FEB: FEB list is empty");
1737
1738         bi.tb = tb;
1739         bi.bi_bh = first_b = tb->FEB[i];
1740         bi.bi_parent = NULL;
1741         bi.bi_position = 0;
1742         make_empty_node(&bi);
1743         set_buffer_uptodate(first_b);
1744         tb->FEB[i] = NULL;
1745         tb->used[i] = first_b;
1746
1747         return (first_b);
1748 }
1749
1750 /* This is now used because reiserfs_free_block has to be able to
1751 ** schedule.
1752 */
1753 static void store_thrown(struct tree_balance *tb, struct buffer_head *bh)
1754 {
1755         int i;
1756
1757         if (buffer_dirty(bh))
1758                 reiserfs_warning(tb->tb_sb,
1759                                  "store_thrown deals with dirty buffer");
1760         for (i = 0; i < ARRAY_SIZE(tb->thrown); i++)
1761                 if (!tb->thrown[i]) {
1762                         tb->thrown[i] = bh;
1763                         get_bh(bh);     /* free_thrown puts this */
1764                         return;
1765                 }
1766         reiserfs_warning(tb->tb_sb, "store_thrown: too many thrown buffers");
1767 }
1768
1769 static void free_thrown(struct tree_balance *tb)
1770 {
1771         int i;
1772         b_blocknr_t blocknr;
1773         for (i = 0; i < ARRAY_SIZE(tb->thrown); i++) {
1774                 if (tb->thrown[i]) {
1775                         blocknr = tb->thrown[i]->b_blocknr;
1776                         if (buffer_dirty(tb->thrown[i]))
1777                                 reiserfs_warning(tb->tb_sb,
1778                                                  "free_thrown deals with dirty buffer %d",
1779                                                  blocknr);
1780                         brelse(tb->thrown[i]);  /* incremented in store_thrown */
1781                         reiserfs_free_block(tb->transaction_handle, NULL,
1782                                             blocknr, 0);
1783                 }
1784         }
1785 }
1786
1787 void reiserfs_invalidate_buffer(struct tree_balance *tb, struct buffer_head *bh)
1788 {
1789         struct block_head *blkh;
1790         blkh = B_BLK_HEAD(bh);
1791         set_blkh_level(blkh, FREE_LEVEL);
1792         set_blkh_nr_item(blkh, 0);
1793
1794         clear_buffer_dirty(bh);
1795         store_thrown(tb, bh);
1796 }
1797
1798 /* Replace n_dest'th key in buffer dest by n_src'th key of buffer src.*/
1799 void replace_key(struct tree_balance *tb, struct buffer_head *dest, int n_dest,
1800                  struct buffer_head *src, int n_src)
1801 {
1802
1803         RFALSE(dest == NULL || src == NULL,
1804                "vs-12305: source or destination buffer is 0 (src=%p, dest=%p)",
1805                src, dest);
1806         RFALSE(!B_IS_KEYS_LEVEL(dest),
1807                "vs-12310: invalid level (%z) for destination buffer. dest must be leaf",
1808                dest);
1809         RFALSE(n_dest < 0 || n_src < 0,
1810                "vs-12315: src(%d) or dest(%d) key number < 0", n_src, n_dest);
1811         RFALSE(n_dest >= B_NR_ITEMS(dest) || n_src >= B_NR_ITEMS(src),
1812                "vs-12320: src(%d(%d)) or dest(%d(%d)) key number is too big",
1813                n_src, B_NR_ITEMS(src), n_dest, B_NR_ITEMS(dest));
1814
1815         if (B_IS_ITEMS_LEVEL(src))
1816                 /* source buffer contains leaf node */
1817                 memcpy(B_N_PDELIM_KEY(dest, n_dest), B_N_PITEM_HEAD(src, n_src),
1818                        KEY_SIZE);
1819         else
1820                 memcpy(B_N_PDELIM_KEY(dest, n_dest), B_N_PDELIM_KEY(src, n_src),
1821                        KEY_SIZE);
1822
1823         do_balance_mark_internal_dirty(tb, dest, 0);
1824 }
1825
1826 int get_left_neighbor_position(struct tree_balance *tb, int h)
1827 {
1828         int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1);
1829
1830         RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FL[h] == NULL,
1831                "vs-12325: FL[%d](%p) or F[%d](%p) does not exist",
1832                h, tb->FL[h], h, PATH_H_PPARENT(tb->tb_path, h));
1833
1834         if (Sh_position == 0)
1835                 return B_NR_ITEMS(tb->FL[h]);
1836         else
1837                 return Sh_position - 1;
1838 }
1839
1840 int get_right_neighbor_position(struct tree_balance *tb, int h)
1841 {
1842         int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1);
1843
1844         RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FR[h] == NULL,
1845                "vs-12330: F[%d](%p) or FR[%d](%p) does not exist",
1846                h, PATH_H_PPARENT(tb->tb_path, h), h, tb->FR[h]);
1847
1848         if (Sh_position == B_NR_ITEMS(PATH_H_PPARENT(tb->tb_path, h)))
1849                 return 0;
1850         else
1851                 return Sh_position + 1;
1852 }
1853
1854 #ifdef CONFIG_REISERFS_CHECK
1855
1856 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value);
1857 static void check_internal_node(struct super_block *s, struct buffer_head *bh,
1858                                 char *mes)
1859 {
1860         struct disk_child *dc;
1861         int i;
1862
1863         RFALSE(!bh, "PAP-12336: bh == 0");
1864
1865         if (!bh || !B_IS_IN_TREE(bh))
1866                 return;
1867
1868         RFALSE(!buffer_dirty(bh) &&
1869                !(buffer_journaled(bh) || buffer_journal_dirty(bh)),
1870                "PAP-12337: buffer (%b) must be dirty", bh);
1871         dc = B_N_CHILD(bh, 0);
1872
1873         for (i = 0; i <= B_NR_ITEMS(bh); i++, dc++) {
1874                 if (!is_reusable(s, dc_block_number(dc), 1)) {
1875                         print_cur_tb(mes);
1876                         reiserfs_panic(s,
1877                                        "PAP-12338: check_internal_node: invalid child pointer %y in %b",
1878                                        dc, bh);
1879                 }
1880         }
1881 }
1882
1883 static int locked_or_not_in_tree(struct buffer_head *bh, char *which)
1884 {
1885         if ((!buffer_journal_prepared(bh) && buffer_locked(bh)) ||
1886             !B_IS_IN_TREE(bh)) {
1887                 reiserfs_warning(NULL,
1888                                  "vs-12339: locked_or_not_in_tree: %s (%b)",
1889                                  which, bh);
1890                 return 1;
1891         }
1892         return 0;
1893 }
1894
1895 static int check_before_balancing(struct tree_balance *tb)
1896 {
1897         int retval = 0;
1898
1899         if (cur_tb) {
1900                 reiserfs_panic(tb->tb_sb, "vs-12335: check_before_balancing: "
1901                                "suspect that schedule occurred based on cur_tb not being null at this point in code. "
1902                                "do_balance cannot properly handle schedule occurring while it runs.");
1903         }
1904
1905         /* double check that buffers that we will modify are unlocked. (fix_nodes should already have
1906            prepped all of these for us). */
1907         if (tb->lnum[0]) {
1908                 retval |= locked_or_not_in_tree(tb->L[0], "L[0]");
1909                 retval |= locked_or_not_in_tree(tb->FL[0], "FL[0]");
1910                 retval |= locked_or_not_in_tree(tb->CFL[0], "CFL[0]");
1911                 check_leaf(tb->L[0]);
1912         }
1913         if (tb->rnum[0]) {
1914                 retval |= locked_or_not_in_tree(tb->R[0], "R[0]");
1915                 retval |= locked_or_not_in_tree(tb->FR[0], "FR[0]");
1916                 retval |= locked_or_not_in_tree(tb->CFR[0], "CFR[0]");
1917                 check_leaf(tb->R[0]);
1918         }
1919         retval |= locked_or_not_in_tree(PATH_PLAST_BUFFER(tb->tb_path), "S[0]");
1920         check_leaf(PATH_PLAST_BUFFER(tb->tb_path));
1921
1922         return retval;
1923 }
1924
1925 static void check_after_balance_leaf(struct tree_balance *tb)
1926 {
1927         if (tb->lnum[0]) {
1928                 if (B_FREE_SPACE(tb->L[0]) !=
1929                     MAX_CHILD_SIZE(tb->L[0]) -
1930                     dc_size(B_N_CHILD
1931                             (tb->FL[0], get_left_neighbor_position(tb, 0)))) {
1932                         print_cur_tb("12221");
1933                         reiserfs_panic(tb->tb_sb,
1934                                        "PAP-12355: check_after_balance_leaf: shift to left was incorrect");
1935                 }
1936         }
1937         if (tb->rnum[0]) {
1938                 if (B_FREE_SPACE(tb->R[0]) !=
1939                     MAX_CHILD_SIZE(tb->R[0]) -
1940                     dc_size(B_N_CHILD
1941                             (tb->FR[0], get_right_neighbor_position(tb, 0)))) {
1942                         print_cur_tb("12222");
1943                         reiserfs_panic(tb->tb_sb,
1944                                        "PAP-12360: check_after_balance_leaf: shift to right was incorrect");
1945                 }
1946         }
1947         if (PATH_H_PBUFFER(tb->tb_path, 1) &&
1948             (B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0)) !=
1949              (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) -
1950               dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1),
1951                                 PATH_H_POSITION(tb->tb_path, 1)))))) {
1952                 int left = B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0));
1953                 int right = (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) -
1954                              dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1),
1955                                                PATH_H_POSITION(tb->tb_path,
1956                                                                1))));
1957                 print_cur_tb("12223");
1958                 reiserfs_warning(tb->tb_sb,
1959                                  "B_FREE_SPACE (PATH_H_PBUFFER(tb->tb_path,0)) = %d; "
1960                                  "MAX_CHILD_SIZE (%d) - dc_size( %y, %d ) [%d] = %d",
1961                                  left,
1962                                  MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)),
1963                                  PATH_H_PBUFFER(tb->tb_path, 1),
1964                                  PATH_H_POSITION(tb->tb_path, 1),
1965                                  dc_size(B_N_CHILD
1966                                          (PATH_H_PBUFFER(tb->tb_path, 1),
1967                                           PATH_H_POSITION(tb->tb_path, 1))),
1968                                  right);
1969                 reiserfs_panic(tb->tb_sb,
1970                                "PAP-12365: check_after_balance_leaf: S is incorrect");
1971         }
1972 }
1973
1974 static void check_leaf_level(struct tree_balance *tb)
1975 {
1976         check_leaf(tb->L[0]);
1977         check_leaf(tb->R[0]);
1978         check_leaf(PATH_PLAST_BUFFER(tb->tb_path));
1979 }
1980
1981 static void check_internal_levels(struct tree_balance *tb)
1982 {
1983         int h;
1984
1985         /* check all internal nodes */
1986         for (h = 1; tb->insert_size[h]; h++) {
1987                 check_internal_node(tb->tb_sb, PATH_H_PBUFFER(tb->tb_path, h),
1988                                     "BAD BUFFER ON PATH");
1989                 if (tb->lnum[h])
1990                         check_internal_node(tb->tb_sb, tb->L[h], "BAD L");
1991                 if (tb->rnum[h])
1992                         check_internal_node(tb->tb_sb, tb->R[h], "BAD R");
1993         }
1994
1995 }
1996
1997 #endif
1998
1999 /* Now we have all of the buffers that must be used in balancing of
2000    the tree.  We rely on the assumption that schedule() will not occur
2001    while do_balance works. ( Only interrupt handlers are acceptable.)
2002    We balance the tree according to the analysis made before this,
2003    using buffers already obtained.  For SMP support it will someday be
2004    necessary to add ordered locking of tb. */
2005
2006 /* Some interesting rules of balancing:
2007
2008    we delete a maximum of two nodes per level per balancing: we never
2009    delete R, when we delete two of three nodes L, S, R then we move
2010    them into R.
2011
2012    we only delete L if we are deleting two nodes, if we delete only
2013    one node we delete S
2014
2015    if we shift leaves then we shift as much as we can: this is a
2016    deliberate policy of extremism in node packing which results in
2017    higher average utilization after repeated random balance operations
2018    at the cost of more memory copies and more balancing as a result of
2019    small insertions to full nodes.
2020
2021    if we shift internal nodes we try to evenly balance the node
2022    utilization, with consequent less balancing at the cost of lower
2023    utilization.
2024
2025    one could argue that the policy for directories in leaves should be
2026    that of internal nodes, but we will wait until another day to
2027    evaluate this....  It would be nice to someday measure and prove
2028    these assumptions as to what is optimal....
2029
2030 */
2031
2032 static inline void do_balance_starts(struct tree_balance *tb)
2033 {
2034         /* use print_cur_tb() to see initial state of struct
2035            tree_balance */
2036
2037         /* store_print_tb (tb); */
2038
2039         /* do not delete, just comment it out */
2040 /*    print_tb(flag, PATH_LAST_POSITION(tb->tb_path), tb->tb_path->pos_in_item, tb,
2041              "check");*/
2042         RFALSE(check_before_balancing(tb), "PAP-12340: locked buffers in TB");
2043 #ifdef CONFIG_REISERFS_CHECK
2044         cur_tb = tb;
2045 #endif
2046 }
2047
2048 static inline void do_balance_completed(struct tree_balance *tb)
2049 {
2050
2051 #ifdef CONFIG_REISERFS_CHECK
2052         check_leaf_level(tb);
2053         check_internal_levels(tb);
2054         cur_tb = NULL;
2055 #endif
2056
2057         /* reiserfs_free_block is no longer schedule safe.  So, we need to
2058          ** put the buffers we want freed on the thrown list during do_balance,
2059          ** and then free them now
2060          */
2061
2062         REISERFS_SB(tb->tb_sb)->s_do_balance++;
2063
2064         /* release all nodes hold to perform the balancing */
2065         unfix_nodes(tb);
2066
2067         free_thrown(tb);
2068 }
2069
2070 void do_balance(struct tree_balance *tb,        /* tree_balance structure */
2071                 struct item_head *ih,   /* item header of inserted item */
2072                 const char *body,       /* body  of inserted item or bytes to paste */
2073                 int flag)
2074 {                               /* i - insert, d - delete
2075                                    c - cut, p - paste
2076
2077                                    Cut means delete part of an item
2078                                    (includes removing an entry from a
2079                                    directory).
2080
2081                                    Delete means delete whole item.
2082
2083                                    Insert means add a new item into the
2084                                    tree.
2085
2086                                    Paste means to append to the end of an
2087                                    existing file or to insert a directory
2088                                    entry.  */
2089         int child_pos,          /* position of a child node in its parent */
2090          h;                     /* level of the tree being processed */
2091         struct item_head insert_key[2]; /* in our processing of one level
2092                                            we sometimes determine what
2093                                            must be inserted into the next
2094                                            higher level.  This insertion
2095                                            consists of a key or two keys
2096                                            and their corresponding
2097                                            pointers */
2098         struct buffer_head *insert_ptr[2];      /* inserted node-ptrs for the next
2099                                                    level */
2100
2101         tb->tb_mode = flag;
2102         tb->need_balance_dirty = 0;
2103
2104         if (FILESYSTEM_CHANGED_TB(tb)) {
2105                 reiserfs_panic(tb->tb_sb,
2106                                "clm-6000: do_balance, fs generation has changed\n");
2107         }
2108         /* if we have no real work to do  */
2109         if (!tb->insert_size[0]) {
2110                 reiserfs_warning(tb->tb_sb,
2111                                  "PAP-12350: do_balance: insert_size == 0, mode == %c",
2112                                  flag);
2113                 unfix_nodes(tb);
2114                 return;
2115         }
2116
2117         atomic_inc(&(fs_generation(tb->tb_sb)));
2118         do_balance_starts(tb);
2119
2120         /* balance leaf returns 0 except if combining L R and S into
2121            one node.  see balance_internal() for explanation of this
2122            line of code. */
2123         child_pos = PATH_H_B_ITEM_ORDER(tb->tb_path, 0) +
2124             balance_leaf(tb, ih, body, flag, insert_key, insert_ptr);
2125
2126 #ifdef CONFIG_REISERFS_CHECK
2127         check_after_balance_leaf(tb);
2128 #endif
2129
2130         /* Balance internal level of the tree. */
2131         for (h = 1; h < MAX_HEIGHT && tb->insert_size[h]; h++)
2132                 child_pos =
2133                     balance_internal(tb, h, child_pos, insert_key, insert_ptr);
2134
2135         do_balance_completed(tb);
2136
2137 }