fs/reiserfs/do

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This source file includes following definitions.
buffer_info_init_left
buffer_info_init_right
buffer_info_init_tbS0
buffer_info_init_bh
do_balance_mark_leaf_dirty
balance_leaf_when_delete_del
balance_leaf_when_delete_cut
balance_leaf_when_delete_left
balance_leaf_when_delete
balance_leaf_insert_left
balance_leaf_paste_left_shift_dirent
balance_leaf_paste_left_shift
balance_leaf_paste_left_whole
balance_leaf_paste_left
balance_leaf_left
balance_leaf_insert_right
balance_leaf_paste_right_shift_dirent
balance_leaf_paste_right_shift
balance_leaf_paste_right_whole
balance_leaf_paste_right
balance_leaf_right
balance_leaf_new_nodes_insert
balance_leaf_new_nodes_paste_dirent
balance_leaf_new_nodes_paste_shift
balance_leaf_new_nodes_paste_whole
balance_leaf_new_nodes_paste
balance_leaf_new_nodes
balance_leaf_finish_node_insert
balance_leaf_finish_node_paste_dirent
balance_leaf_finish_node_paste
balance_leaf_finish_node
balance_leaf
make_empty_node
get_FEB
store_thrown
free_thrown
reiserfs_invalidate_buffer
replace_key
get_left_neighbor_position
get_right_neighbor_position
check_internal_node
locked_or_not_in_tree
check_before_balancing
check_after_balance_leaf
check_leaf_level
check_internal_levels
do_balance_starts
do_balance_completed
do_balance
   1 /*
   2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
   3  */
   4 
   5 /*
   6  * Now we have all buffers that must be used in balancing of the tree
   7  * Further calculations can not cause schedule(), and thus the buffer
   8  * tree will be stable until the balancing will be finished
   9  * balance the tree according to the analysis made before,
  10  * and using buffers obtained after all above.
  11  */
  12 
  13 #include <linux/uaccess.h>
  14 #include <linux/time.h>
  15 #include "reiserfs.h"
  16 #include <linux/buffer_head.h>
  17 #include <linux/kernel.h>
  18 
  19 static inline void buffer_info_init_left(struct tree_balance *tb,
  20                                          struct buffer_info *bi)
  21 {
  22         bi->tb          = tb;
  23         bi->bi_bh       = tb->L[0];
  24         bi->bi_parent   = tb->FL[0];
  25         bi->bi_position = get_left_neighbor_position(tb, 0);
  26 }
  27 
  28 static inline void buffer_info_init_right(struct tree_balance *tb,
  29                                           struct buffer_info *bi)
  30 {
  31         bi->tb          = tb;
  32         bi->bi_bh       = tb->R[0];
  33         bi->bi_parent   = tb->FR[0];
  34         bi->bi_position = get_right_neighbor_position(tb, 0);
  35 }
  36 
  37 static inline void buffer_info_init_tbS0(struct tree_balance *tb,
  38                                          struct buffer_info *bi)
  39 {
  40         bi->tb          = tb;
  41         bi->bi_bh        = PATH_PLAST_BUFFER(tb->tb_path);
  42         bi->bi_parent   = PATH_H_PPARENT(tb->tb_path, 0);
  43         bi->bi_position = PATH_H_POSITION(tb->tb_path, 1);
  44 }
  45 
  46 static inline void buffer_info_init_bh(struct tree_balance *tb,
  47                                        struct buffer_info *bi,
  48                                        struct buffer_head *bh)
  49 {
  50         bi->tb          = tb;
  51         bi->bi_bh       = bh;
  52         bi->bi_parent   = NULL;
  53         bi->bi_position = 0;
  54 }
  55 
  56 inline void do_balance_mark_leaf_dirty(struct tree_balance *tb,
  57                                        struct buffer_head *bh, int flag)
  58 {
  59         journal_mark_dirty(tb->transaction_handle, bh);
  60 }
  61 
  62 #define do_balance_mark_internal_dirty do_balance_mark_leaf_dirty
  63 #define do_balance_mark_sb_dirty do_balance_mark_leaf_dirty
  64 
  65 /*
  66  * summary:
  67  *  if deleting something ( tb->insert_size[0] < 0 )
  68  *    return(balance_leaf_when_delete()); (flag d handled here)
  69  *  else
  70  *    if lnum is larger than 0 we put items into the left node
  71  *    if rnum is larger than 0 we put items into the right node
  72  *    if snum1 is larger than 0 we put items into the new node s1
  73  *    if snum2 is larger than 0 we put items into the new node s2
  74  * Note that all *num* count new items being created.
  75  */
  76 
  77 static void balance_leaf_when_delete_del(struct tree_balance *tb)
  78 {
  79         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
  80         int item_pos = PATH_LAST_POSITION(tb->tb_path);
  81         struct buffer_info bi;
  82 #ifdef CONFIG_REISERFS_CHECK
  83         struct item_head *ih = item_head(tbS0, item_pos);
  84 #endif
  85 
  86         RFALSE(ih_item_len(ih) + IH_SIZE != -tb->insert_size[0],
  87                "vs-12013: mode Delete, insert size %d, ih to be deleted %h",
  88                -tb->insert_size[0], ih);
  89 
  90         buffer_info_init_tbS0(tb, &bi);
  91         leaf_delete_items(&bi, 0, item_pos, 1, -1);
  92 
  93         if (!item_pos && tb->CFL[0]) {
  94                 if (B_NR_ITEMS(tbS0)) {
  95                         replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0);
  96                 } else {
  97                         if (!PATH_H_POSITION(tb->tb_path, 1))
  98                                 replace_key(tb, tb->CFL[0], tb->lkey[0],
  99                                             PATH_H_PPARENT(tb->tb_path, 0), 0);
 100                 }
 101         }
 102 
 103         RFALSE(!item_pos && !tb->CFL[0],
 104                "PAP-12020: tb->CFL[0]==%p, tb->L[0]==%p", tb->CFL[0],
 105                tb->L[0]);
 106 }
 107 
 108 /* cut item in S[0] */
 109 static void balance_leaf_when_delete_cut(struct tree_balance *tb)
 110 {
 111         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 112         int item_pos = PATH_LAST_POSITION(tb->tb_path);
 113         struct item_head *ih = item_head(tbS0, item_pos);
 114         int pos_in_item = tb->tb_path->pos_in_item;
 115         struct buffer_info bi;
 116         buffer_info_init_tbS0(tb, &bi);
 117 
 118         if (is_direntry_le_ih(ih)) {
 119                 /*
 120                  * UFS unlink semantics are such that you can only
 121                  * delete one directory entry at a time.
 122                  *
 123                  * when we cut a directory tb->insert_size[0] means
 124                  * number of entries to be cut (always 1)
 125                  */
 126                 tb->insert_size[0] = -1;
 127                 leaf_cut_from_buffer(&bi, item_pos, pos_in_item,
 128                                      -tb->insert_size[0]);
 129 
 130                 RFALSE(!item_pos && !pos_in_item && !tb->CFL[0],
 131                        "PAP-12030: can not change delimiting key. CFL[0]=%p",
 132                        tb->CFL[0]);
 133 
 134                 if (!item_pos && !pos_in_item && tb->CFL[0])
 135                         replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0);
 136         } else {
 137                 leaf_cut_from_buffer(&bi, item_pos, pos_in_item,
 138                                      -tb->insert_size[0]);
 139 
 140                 RFALSE(!ih_item_len(ih),
 141                        "PAP-12035: cut must leave non-zero dynamic "
 142                        "length of item");
 143         }
 144 }
 145 
 146 static int balance_leaf_when_delete_left(struct tree_balance *tb)
 147 {
 148         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 149         int n = B_NR_ITEMS(tbS0);
 150 
 151         /* L[0] must be joined with S[0] */
 152         if (tb->lnum[0] == -1) {
 153                 /* R[0] must be also joined with S[0] */
 154                 if (tb->rnum[0] == -1) {
 155                         if (tb->FR[0] == PATH_H_PPARENT(tb->tb_path, 0)) {
 156                                 /*
 157                                  * all contents of all the
 158                                  * 3 buffers will be in L[0]
 159                                  */
 160                                 if (PATH_H_POSITION(tb->tb_path, 1) == 0 &&
 161                                     1 < B_NR_ITEMS(tb->FR[0]))
 162                                         replace_key(tb, tb->CFL[0],
 163                                                     tb->lkey[0], tb->FR[0], 1);
 164 
 165                                 leaf_move_items(LEAF_FROM_S_TO_L, tb, n, -1,
 166                                                 NULL);
 167                                 leaf_move_items(LEAF_FROM_R_TO_L, tb,
 168                                                 B_NR_ITEMS(tb->R[0]), -1,
 169                                                 NULL);
 170 
 171                                 reiserfs_invalidate_buffer(tb, tbS0);
 172                                 reiserfs_invalidate_buffer(tb, tb->R[0]);
 173 
 174                                 return 0;
 175                         }
 176 
 177                         /* all contents of all the 3 buffers will be in R[0] */
 178                         leaf_move_items(LEAF_FROM_S_TO_R, tb, n, -1, NULL);
 179                         leaf_move_items(LEAF_FROM_L_TO_R, tb,
 180                                         B_NR_ITEMS(tb->L[0]), -1, NULL);
 181 
 182                         /* right_delimiting_key is correct in R[0] */
 183                         replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
 184 
 185                         reiserfs_invalidate_buffer(tb, tbS0);
 186                         reiserfs_invalidate_buffer(tb, tb->L[0]);
 187 
 188                         return -1;
 189                 }
 190 
 191                 RFALSE(tb->rnum[0] != 0,
 192                        "PAP-12045: rnum must be 0 (%d)", tb->rnum[0]);
 193                 /* all contents of L[0] and S[0] will be in L[0] */
 194                 leaf_shift_left(tb, n, -1);
 195 
 196                 reiserfs_invalidate_buffer(tb, tbS0);
 197 
 198                 return 0;
 199         }
 200 
 201         /*
 202          * a part of contents of S[0] will be in L[0] and
 203          * the rest part of S[0] will be in R[0]
 204          */
 205 
 206         RFALSE((tb->lnum[0] + tb->rnum[0] < n) ||
 207                (tb->lnum[0] + tb->rnum[0] > n + 1),
 208                "PAP-12050: rnum(%d) and lnum(%d) and item "
 209                "number(%d) in S[0] are not consistent",
 210                tb->rnum[0], tb->lnum[0], n);
 211         RFALSE((tb->lnum[0] + tb->rnum[0] == n) &&
 212                (tb->lbytes != -1 || tb->rbytes != -1),
 213                "PAP-12055: bad rbytes (%d)/lbytes (%d) "
 214                "parameters when items are not split",
 215                tb->rbytes, tb->lbytes);
 216         RFALSE((tb->lnum[0] + tb->rnum[0] == n + 1) &&
 217                (tb->lbytes < 1 || tb->rbytes != -1),
 218                "PAP-12060: bad rbytes (%d)/lbytes (%d) "
 219                "parameters when items are split",
 220                tb->rbytes, tb->lbytes);
 221 
 222         leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
 223         leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
 224 
 225         reiserfs_invalidate_buffer(tb, tbS0);
 226 
 227         return 0;
 228 }
 229 
 230 /*
 231  * Balance leaf node in case of delete or cut: insert_size[0] < 0
 232  *
 233  * lnum, rnum can have values >= -1
 234  *      -1 means that the neighbor must be joined with S
 235  *       0 means that nothing should be done with the neighbor
 236  *      >0 means to shift entirely or partly the specified number of items
 237  *         to the neighbor
 238  */
 239 static int balance_leaf_when_delete(struct tree_balance *tb, int flag)
 240 {
 241         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 242         struct buffer_info bi;
 243         int n;
 244 
 245         RFALSE(tb->FR[0] && B_LEVEL(tb->FR[0]) != DISK_LEAF_NODE_LEVEL + 1,
 246                "vs- 12000: level: wrong FR %z", tb->FR[0]);
 247         RFALSE(tb->blknum[0] > 1,
 248                "PAP-12005: tb->blknum == %d, can not be > 1", tb->blknum[0]);
 249         RFALSE(!tb->blknum[0] && !PATH_H_PPARENT(tb->tb_path, 0),
 250                "PAP-12010: tree can not be empty");
 251 
 252         buffer_info_init_tbS0(tb, &bi);
 253 
 254         /* Delete or truncate the item */
 255 
 256         BUG_ON(flag != M_DELETE && flag != M_CUT);
 257         if (flag == M_DELETE)
 258                 balance_leaf_when_delete_del(tb);
 259         else /* M_CUT */
 260                 balance_leaf_when_delete_cut(tb);
 261 
 262 
 263         /*
 264          * the rule is that no shifting occurs unless by shifting
 265          * a node can be freed
 266          */
 267         n = B_NR_ITEMS(tbS0);
 268 
 269 
 270         /* L[0] takes part in balancing */
 271         if (tb->lnum[0])
 272                 return balance_leaf_when_delete_left(tb);
 273 
 274         if (tb->rnum[0] == -1) {
 275                 /* all contents of R[0] and S[0] will be in R[0] */
 276                 leaf_shift_right(tb, n, -1);
 277                 reiserfs_invalidate_buffer(tb, tbS0);
 278                 return 0;
 279         }
 280 
 281         RFALSE(tb->rnum[0],
 282                "PAP-12065: bad rnum parameter must be 0 (%d)", tb->rnum[0]);
 283         return 0;
 284 }
 285 
 286 static unsigned int balance_leaf_insert_left(struct tree_balance *tb,
 287                                              struct item_head *const ih,
 288                                              const char * const body)
 289 {
 290         int ret;
 291         struct buffer_info bi;
 292         int n = B_NR_ITEMS(tb->L[0]);
 293         unsigned body_shift_bytes = 0;
 294 
 295         if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1) {
 296                 /* part of new item falls into L[0] */
 297                 int new_item_len, shift;
 298 
 299                 ret = leaf_shift_left(tb, tb->lnum[0] - 1, -1);
 300 
 301                 /* Calculate item length to insert to S[0] */
 302                 new_item_len = ih_item_len(ih) - tb->lbytes;
 303 
 304                 /* Calculate and check item length to insert to L[0] */
 305                 put_ih_item_len(ih, ih_item_len(ih) - new_item_len);
 306 
 307                 RFALSE(ih_item_len(ih) <= 0,
 308                        "PAP-12080: there is nothing to insert into L[0]: "
 309                        "ih_item_len=%d", ih_item_len(ih));
 310 
 311                 /* Insert new item into L[0] */
 312                 buffer_info_init_left(tb, &bi);
 313                 leaf_insert_into_buf(&bi, n + tb->item_pos - ret, ih, body,
 314                              min_t(int, tb->zeroes_num, ih_item_len(ih)));
 315 
 316                 /*
 317                  * Calculate key component, item length and body to
 318                  * insert into S[0]
 319                  */
 320                 shift = 0;
 321                 if (is_indirect_le_ih(ih))
 322                         shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
 323 
 324                 add_le_ih_k_offset(ih, tb->lbytes << shift);
 325 
 326                 put_ih_item_len(ih, new_item_len);
 327                 if (tb->lbytes > tb->zeroes_num) {
 328                         body_shift_bytes = tb->lbytes - tb->zeroes_num;
 329                         tb->zeroes_num = 0;
 330                 } else
 331                         tb->zeroes_num -= tb->lbytes;
 332 
 333                 RFALSE(ih_item_len(ih) <= 0,
 334                        "PAP-12085: there is nothing to insert into S[0]: "
 335                        "ih_item_len=%d", ih_item_len(ih));
 336         } else {
 337                 /* new item in whole falls into L[0] */
 338                 /* Shift lnum[0]-1 items to L[0] */
 339                 ret = leaf_shift_left(tb, tb->lnum[0] - 1, tb->lbytes);
 340 
 341                 /* Insert new item into L[0] */
 342                 buffer_info_init_left(tb, &bi);
 343                 leaf_insert_into_buf(&bi, n + tb->item_pos - ret, ih, body,
 344                                      tb->zeroes_num);
 345                 tb->insert_size[0] = 0;
 346                 tb->zeroes_num = 0;
 347         }
 348         return body_shift_bytes;
 349 }
 350 
 351 static void balance_leaf_paste_left_shift_dirent(struct tree_balance *tb,
 352                                                  struct item_head * const ih,
 353                                                  const char * const body)
 354 {
 355         int n = B_NR_ITEMS(tb->L[0]);
 356         struct buffer_info bi;
 357 
 358         RFALSE(tb->zeroes_num,
 359                "PAP-12090: invalid parameter in case of a directory");
 360 
 361         /* directory item */
 362         if (tb->lbytes > tb->pos_in_item) {
 363                 /* new directory entry falls into L[0] */
 364                 struct item_head *pasted;
 365                 int ret, l_pos_in_item = tb->pos_in_item;
 366 
 367                 /*
 368                  * Shift lnum[0] - 1 items in whole.
 369                  * Shift lbytes - 1 entries from given directory item
 370                  */
 371                 ret = leaf_shift_left(tb, tb->lnum[0], tb->lbytes - 1);
 372                 if (ret && !tb->item_pos) {
 373                         pasted = item_head(tb->L[0], B_NR_ITEMS(tb->L[0]) - 1);
 374                         l_pos_in_item += ih_entry_count(pasted) -
 375                                          (tb->lbytes - 1);
 376                 }
 377 
 378                 /* Append given directory entry to directory item */
 379                 buffer_info_init_left(tb, &bi);
 380                 leaf_paste_in_buffer(&bi, n + tb->item_pos - ret,
 381                                      l_pos_in_item, tb->insert_size[0],
 382                                      body, tb->zeroes_num);
 383 
 384                 /*
 385                  * previous string prepared space for pasting new entry,
 386                  * following string pastes this entry
 387                  */
 388 
 389                 /*
 390                  * when we have merge directory item, pos_in_item
 391                  * has been changed too
 392                  */
 393 
 394                 /* paste new directory entry. 1 is entry number */
 395                 leaf_paste_entries(&bi, n + tb->item_pos - ret,
 396                                    l_pos_in_item, 1,
 397                                    (struct reiserfs_de_head *) body,
 398                                    body + DEH_SIZE, tb->insert_size[0]);
 399                 tb->insert_size[0] = 0;
 400         } else {
 401                 /* new directory item doesn't fall into L[0] */
 402                 /*
 403                  * Shift lnum[0]-1 items in whole. Shift lbytes
 404                  * directory entries from directory item number lnum[0]
 405                  */
 406                 leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
 407         }
 408 
 409         /* Calculate new position to append in item body */
 410         tb->pos_in_item -= tb->lbytes;
 411 }
 412 
 413 static unsigned int balance_leaf_paste_left_shift(struct tree_balance *tb,
 414                                                   struct item_head * const ih,
 415                                                   const char * const body)
 416 {
 417         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 418         int n = B_NR_ITEMS(tb->L[0]);
 419         struct buffer_info bi;
 420         int body_shift_bytes = 0;
 421 
 422         if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) {
 423                 balance_leaf_paste_left_shift_dirent(tb, ih, body);
 424                 return 0;
 425         }
 426 
 427         RFALSE(tb->lbytes <= 0,
 428                "PAP-12095: there is nothing to shift to L[0]. "
 429                "lbytes=%d", tb->lbytes);
 430         RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)),
 431                "PAP-12100: incorrect position to paste: "
 432                "item_len=%d, pos_in_item=%d",
 433                ih_item_len(item_head(tbS0, tb->item_pos)), tb->pos_in_item);
 434 
 435         /* appended item will be in L[0] in whole */
 436         if (tb->lbytes >= tb->pos_in_item) {
 437                 struct item_head *tbS0_pos_ih, *tbL0_ih;
 438                 struct item_head *tbS0_0_ih;
 439                 struct reiserfs_key *left_delim_key;
 440                 int ret, l_n, version, temp_l;
 441 
 442                 tbS0_pos_ih = item_head(tbS0, tb->item_pos);
 443                 tbS0_0_ih = item_head(tbS0, 0);
 444 
 445                 /*
 446                  * this bytes number must be appended
 447                  * to the last item of L[h]
 448                  */
 449                 l_n = tb->lbytes - tb->pos_in_item;
 450 
 451                 /* Calculate new insert_size[0] */
 452                 tb->insert_size[0] -= l_n;
 453 
 454                 RFALSE(tb->insert_size[0] <= 0,
 455                        "PAP-12105: there is nothing to paste into "
 456                        "L[0]. insert_size=%d", tb->insert_size[0]);
 457 
 458                 ret = leaf_shift_left(tb, tb->lnum[0],
 459                                       ih_item_len(tbS0_pos_ih));
 460 
 461                 tbL0_ih = item_head(tb->L[0], n + tb->item_pos - ret);
 462 
 463                 /* Append to body of item in L[0] */
 464                 buffer_info_init_left(tb, &bi);
 465                 leaf_paste_in_buffer(&bi, n + tb->item_pos - ret,
 466                                      ih_item_len(tbL0_ih), l_n, body,
 467                                      min_t(int, l_n, tb->zeroes_num));
 468 
 469                 /*
 470                  * 0-th item in S0 can be only of DIRECT type
 471                  * when l_n != 0
 472                  */
 473                 temp_l = l_n;
 474 
 475                 RFALSE(ih_item_len(tbS0_0_ih),
 476                        "PAP-12106: item length must be 0");
 477                 RFALSE(comp_short_le_keys(&tbS0_0_ih->ih_key,
 478                        leaf_key(tb->L[0], n + tb->item_pos - ret)),
 479                        "PAP-12107: items must be of the same file");
 480 
 481                 if (is_indirect_le_ih(tbL0_ih)) {
 482                         int shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
 483                         temp_l = l_n << shift;
 484                 }
 485                 /* update key of first item in S0 */
 486                 version = ih_version(tbS0_0_ih);
 487                 add_le_key_k_offset(version, &tbS0_0_ih->ih_key, temp_l);
 488 
 489                 /* update left delimiting key */
 490                 left_delim_key = internal_key(tb->CFL[0], tb->lkey[0]);
 491                 add_le_key_k_offset(version, left_delim_key, temp_l);
 492 
 493                 /*
 494                  * Calculate new body, position in item and
 495                  * insert_size[0]
 496                  */
 497                 if (l_n > tb->zeroes_num) {
 498                         body_shift_bytes = l_n - tb->zeroes_num;
 499                         tb->zeroes_num = 0;
 500                 } else
 501                         tb->zeroes_num -= l_n;
 502                 tb->pos_in_item = 0;
 503 
 504                 RFALSE(comp_short_le_keys(&tbS0_0_ih->ih_key,
 505                                           leaf_key(tb->L[0],
 506                                                  B_NR_ITEMS(tb->L[0]) - 1)) ||
 507                        !op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size) ||
 508                        !op_is_left_mergeable(left_delim_key, tbS0->b_size),
 509                        "PAP-12120: item must be merge-able with left "
 510                        "neighboring item");
 511         } else {
 512                 /* only part of the appended item will be in L[0] */
 513 
 514                 /* Calculate position in item for append in S[0] */
 515                 tb->pos_in_item -= tb->lbytes;
 516 
 517                 RFALSE(tb->pos_in_item <= 0,
 518                        "PAP-12125: no place for paste. pos_in_item=%d",
 519                        tb->pos_in_item);
 520 
 521                 /*
 522                  * Shift lnum[0] - 1 items in whole.
 523                  * Shift lbytes - 1 byte from item number lnum[0]
 524                  */
 525                 leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
 526         }
 527         return body_shift_bytes;
 528 }
 529 
 530 
 531 /* appended item will be in L[0] in whole */
 532 static void balance_leaf_paste_left_whole(struct tree_balance *tb,
 533                                           struct item_head * const ih,
 534                                           const char * const body)
 535 {
 536         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 537         int n = B_NR_ITEMS(tb->L[0]);
 538         struct buffer_info bi;
 539         struct item_head *pasted;
 540         int ret;
 541 
 542         /* if we paste into first item of S[0] and it is left mergable */
 543         if (!tb->item_pos &&
 544             op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size)) {
 545                 /*
 546                  * then increment pos_in_item by the size of the
 547                  * last item in L[0]
 548                  */
 549                 pasted = item_head(tb->L[0], n - 1);
 550                 if (is_direntry_le_ih(pasted))
 551                         tb->pos_in_item += ih_entry_count(pasted);
 552                 else
 553                         tb->pos_in_item += ih_item_len(pasted);
 554         }
 555 
 556         /*
 557          * Shift lnum[0] - 1 items in whole.
 558          * Shift lbytes - 1 byte from item number lnum[0]
 559          */
 560         ret = leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
 561 
 562         /* Append to body of item in L[0] */
 563         buffer_info_init_left(tb, &bi);
 564         leaf_paste_in_buffer(&bi, n + tb->item_pos - ret, tb->pos_in_item,
 565                              tb->insert_size[0], body, tb->zeroes_num);
 566 
 567         /* if appended item is directory, paste entry */
 568         pasted = item_head(tb->L[0], n + tb->item_pos - ret);
 569         if (is_direntry_le_ih(pasted))
 570                 leaf_paste_entries(&bi, n + tb->item_pos - ret,
 571                                    tb->pos_in_item, 1,
 572                                    (struct reiserfs_de_head *)body,
 573                                    body + DEH_SIZE, tb->insert_size[0]);
 574 
 575         /*
 576          * if appended item is indirect item, put unformatted node
 577          * into un list
 578          */
 579         if (is_indirect_le_ih(pasted))
 580                 set_ih_free_space(pasted, 0);
 581 
 582         tb->insert_size[0] = 0;
 583         tb->zeroes_num = 0;
 584 }
 585 
 586 static unsigned int balance_leaf_paste_left(struct tree_balance *tb,
 587                                             struct item_head * const ih,
 588                                             const char * const body)
 589 {
 590         /* we must shift the part of the appended item */
 591         if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1)
 592                 return balance_leaf_paste_left_shift(tb, ih, body);
 593         else
 594                 balance_leaf_paste_left_whole(tb, ih, body);
 595         return 0;
 596 }
 597 
 598 /* Shift lnum[0] items from S[0] to the left neighbor L[0] */
 599 static unsigned int balance_leaf_left(struct tree_balance *tb,
 600                                       struct item_head * const ih,
 601                                       const char * const body, int flag)
 602 {
 603         if (tb->lnum[0] <= 0)
 604                 return 0;
 605 
 606         /* new item or it part falls to L[0], shift it too */
 607         if (tb->item_pos < tb->lnum[0]) {
 608                 BUG_ON(flag != M_INSERT && flag != M_PASTE);
 609 
 610                 if (flag == M_INSERT)
 611                         return balance_leaf_insert_left(tb, ih, body);
 612                 else /* M_PASTE */
 613                         return balance_leaf_paste_left(tb, ih, body);
 614         } else
 615                 /* new item doesn't fall into L[0] */
 616                 leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
 617         return 0;
 618 }
 619 
 620 
 621 static void balance_leaf_insert_right(struct tree_balance *tb,
 622                                       struct item_head * const ih,
 623                                       const char * const body)
 624 {
 625 
 626         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 627         int n = B_NR_ITEMS(tbS0);
 628         struct buffer_info bi;
 629 
 630         /* new item or part of it doesn't fall into R[0] */
 631         if (n - tb->rnum[0] >= tb->item_pos) {
 632                 leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
 633                 return;
 634         }
 635 
 636         /* new item or its part falls to R[0] */
 637 
 638         /* part of new item falls into R[0] */
 639         if (tb->item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1) {
 640                 loff_t old_key_comp, old_len, r_zeroes_number;
 641                 const char *r_body;
 642                 int shift;
 643                 loff_t offset;
 644 
 645                 leaf_shift_right(tb, tb->rnum[0] - 1, -1);
 646 
 647                 /* Remember key component and item length */
 648                 old_key_comp = le_ih_k_offset(ih);
 649                 old_len = ih_item_len(ih);
 650 
 651                 /*
 652                  * Calculate key component and item length to insert
 653                  * into R[0]
 654                  */
 655                 shift = 0;
 656                 if (is_indirect_le_ih(ih))
 657                         shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
 658                 offset = le_ih_k_offset(ih) + ((old_len - tb->rbytes) << shift);
 659                 set_le_ih_k_offset(ih, offset);
 660                 put_ih_item_len(ih, tb->rbytes);
 661 
 662                 /* Insert part of the item into R[0] */
 663                 buffer_info_init_right(tb, &bi);
 664                 if ((old_len - tb->rbytes) > tb->zeroes_num) {
 665                         r_zeroes_number = 0;
 666                         r_body = body + (old_len - tb->rbytes) - tb->zeroes_num;
 667                 } else {
 668                         r_body = body;
 669                         r_zeroes_number = tb->zeroes_num -
 670                                           (old_len - tb->rbytes);
 671                         tb->zeroes_num -= r_zeroes_number;
 672                 }
 673 
 674                 leaf_insert_into_buf(&bi, 0, ih, r_body, r_zeroes_number);
 675 
 676                 /* Replace right delimiting key by first key in R[0] */
 677                 replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
 678 
 679                 /*
 680                  * Calculate key component and item length to
 681                  * insert into S[0]
 682                  */
 683                 set_le_ih_k_offset(ih, old_key_comp);
 684                 put_ih_item_len(ih, old_len - tb->rbytes);
 685 
 686                 tb->insert_size[0] -= tb->rbytes;
 687 
 688         } else {
 689                 /* whole new item falls into R[0] */
 690 
 691                 /* Shift rnum[0]-1 items to R[0] */
 692                 leaf_shift_right(tb, tb->rnum[0] - 1, tb->rbytes);
 693 
 694                 /* Insert new item into R[0] */
 695                 buffer_info_init_right(tb, &bi);
 696                 leaf_insert_into_buf(&bi, tb->item_pos - n + tb->rnum[0] - 1,
 697                                      ih, body, tb->zeroes_num);
 698 
 699                 if (tb->item_pos - n + tb->rnum[0] - 1 == 0)
 700                         replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
 701 
 702                 tb->zeroes_num = tb->insert_size[0] = 0;
 703         }
 704 }
 705 
 706 
 707 static void balance_leaf_paste_right_shift_dirent(struct tree_balance *tb,
 708                                      struct item_head * const ih,
 709                                      const char * const body)
 710 {
 711         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 712         struct buffer_info bi;
 713         int entry_count;
 714 
 715         RFALSE(tb->zeroes_num,
 716                "PAP-12145: invalid parameter in case of a directory");
 717         entry_count = ih_entry_count(item_head(tbS0, tb->item_pos));
 718 
 719         /* new directory entry falls into R[0] */
 720         if (entry_count - tb->rbytes < tb->pos_in_item) {
 721                 int paste_entry_position;
 722 
 723                 RFALSE(tb->rbytes - 1 >= entry_count || !tb->insert_size[0],
 724                        "PAP-12150: no enough of entries to shift to R[0]: "
 725                        "rbytes=%d, entry_count=%d", tb->rbytes, entry_count);
 726 
 727                 /*
 728                  * Shift rnum[0]-1 items in whole.
 729                  * Shift rbytes-1 directory entries from directory
 730                  * item number rnum[0]
 731                  */
 732                 leaf_shift_right(tb, tb->rnum[0], tb->rbytes - 1);
 733 
 734                 /* Paste given directory entry to directory item */
 735                 paste_entry_position = tb->pos_in_item - entry_count +
 736                                        tb->rbytes - 1;
 737                 buffer_info_init_right(tb, &bi);
 738                 leaf_paste_in_buffer(&bi, 0, paste_entry_position,
 739                                      tb->insert_size[0], body, tb->zeroes_num);
 740 
 741                 /* paste entry */
 742                 leaf_paste_entries(&bi, 0, paste_entry_position, 1,
 743                                    (struct reiserfs_de_head *) body,
 744                                    body + DEH_SIZE, tb->insert_size[0]);
 745 
 746                 /* change delimiting keys */
 747                 if (paste_entry_position == 0)
 748                         replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
 749 
 750                 tb->insert_size[0] = 0;
 751                 tb->pos_in_item++;
 752         } else {
 753                 /* new directory entry doesn't fall into R[0] */
 754                 leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
 755         }
 756 }
 757 
 758 static void balance_leaf_paste_right_shift(struct tree_balance *tb,
 759                                      struct item_head * const ih,
 760                                      const char * const body)
 761 {
 762         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 763         int n_shift, n_rem, r_zeroes_number, version;
 764         unsigned long temp_rem;
 765         const char *r_body;
 766         struct buffer_info bi;
 767 
 768         /* we append to directory item */
 769         if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) {
 770                 balance_leaf_paste_right_shift_dirent(tb, ih, body);
 771                 return;
 772         }
 773 
 774         /* regular object */
 775 
 776         /*
 777          * Calculate number of bytes which must be shifted
 778          * from appended item
 779          */
 780         n_shift = tb->rbytes - tb->insert_size[0];
 781         if (n_shift < 0)
 782                 n_shift = 0;
 783 
 784         RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)),
 785                "PAP-12155: invalid position to paste. ih_item_len=%d, "
 786                "pos_in_item=%d", tb->pos_in_item,
 787                ih_item_len(item_head(tbS0, tb->item_pos)));
 788 
 789         leaf_shift_right(tb, tb->rnum[0], n_shift);
 790 
 791         /*
 792          * Calculate number of bytes which must remain in body
 793          * after appending to R[0]
 794          */
 795         n_rem = tb->insert_size[0] - tb->rbytes;
 796         if (n_rem < 0)
 797                 n_rem = 0;
 798 
 799         temp_rem = n_rem;
 800 
 801         version = ih_version(item_head(tb->R[0], 0));
 802 
 803         if (is_indirect_le_key(version, leaf_key(tb->R[0], 0))) {
 804                 int shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
 805                 temp_rem = n_rem << shift;
 806         }
 807 
 808         add_le_key_k_offset(version, leaf_key(tb->R[0], 0), temp_rem);
 809         add_le_key_k_offset(version, internal_key(tb->CFR[0], tb->rkey[0]),
 810                             temp_rem);
 811 
 812         do_balance_mark_internal_dirty(tb, tb->CFR[0], 0);
 813 
 814         /* Append part of body into R[0] */
 815         buffer_info_init_right(tb, &bi);
 816         if (n_rem > tb->zeroes_num) {
 817                 r_zeroes_number = 0;
 818                 r_body = body + n_rem - tb->zeroes_num;
 819         } else {
 820                 r_body = body;
 821                 r_zeroes_number = tb->zeroes_num - n_rem;
 822                 tb->zeroes_num -= r_zeroes_number;
 823         }
 824 
 825         leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem,
 826                              r_body, r_zeroes_number);
 827 
 828         if (is_indirect_le_ih(item_head(tb->R[0], 0)))
 829                 set_ih_free_space(item_head(tb->R[0], 0), 0);
 830 
 831         tb->insert_size[0] = n_rem;
 832         if (!n_rem)
 833                 tb->pos_in_item++;
 834 }
 835 
 836 static void balance_leaf_paste_right_whole(struct tree_balance *tb,
 837                                      struct item_head * const ih,
 838                                      const char * const body)
 839 {
 840         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 841         int n = B_NR_ITEMS(tbS0);
 842         struct item_head *pasted;
 843         struct buffer_info bi;
 844 
 845                                                         buffer_info_init_right(tb, &bi);
 846         leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
 847 
 848         /* append item in R[0] */
 849         if (tb->pos_in_item >= 0) {
 850                 buffer_info_init_right(tb, &bi);
 851                 leaf_paste_in_buffer(&bi, tb->item_pos - n + tb->rnum[0],
 852                                      tb->pos_in_item, tb->insert_size[0], body,
 853                                      tb->zeroes_num);
 854         }
 855 
 856         /* paste new entry, if item is directory item */
 857         pasted = item_head(tb->R[0], tb->item_pos - n + tb->rnum[0]);
 858         if (is_direntry_le_ih(pasted) && tb->pos_in_item >= 0) {
 859                 leaf_paste_entries(&bi, tb->item_pos - n + tb->rnum[0],
 860                                    tb->pos_in_item, 1,
 861                                    (struct reiserfs_de_head *)body,
 862                                    body + DEH_SIZE, tb->insert_size[0]);
 863 
 864                 if (!tb->pos_in_item) {
 865 
 866                         RFALSE(tb->item_pos - n + tb->rnum[0],
 867                                "PAP-12165: directory item must be first "
 868                                "item of node when pasting is in 0th position");
 869 
 870                         /* update delimiting keys */
 871                         replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
 872                 }
 873         }
 874 
 875         if (is_indirect_le_ih(pasted))
 876                 set_ih_free_space(pasted, 0);
 877         tb->zeroes_num = tb->insert_size[0] = 0;
 878 }
 879 
 880 static void balance_leaf_paste_right(struct tree_balance *tb,
 881                                      struct item_head * const ih,
 882                                      const char * const body)
 883 {
 884         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 885         int n = B_NR_ITEMS(tbS0);
 886 
 887         /* new item doesn't fall into R[0] */
 888         if (n - tb->rnum[0] > tb->item_pos) {
 889                 leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
 890                 return;
 891         }
 892 
 893         /* pasted item or part of it falls to R[0] */
 894 
 895         if (tb->item_pos == n - tb->rnum[0] && tb->rbytes != -1)
 896                 /* we must shift the part of the appended item */
 897                 balance_leaf_paste_right_shift(tb, ih, body);
 898         else
 899                 /* pasted item in whole falls into R[0] */
 900                 balance_leaf_paste_right_whole(tb, ih, body);
 901 }
 902 
 903 /* shift rnum[0] items from S[0] to the right neighbor R[0] */
 904 static void balance_leaf_right(struct tree_balance *tb,
 905                                struct item_head * const ih,
 906                                const char * const body, int flag)
 907 {
 908         if (tb->rnum[0] <= 0)
 909                 return;
 910 
 911         BUG_ON(flag != M_INSERT && flag != M_PASTE);
 912 
 913         if (flag == M_INSERT)
 914                 balance_leaf_insert_right(tb, ih, body);
 915         else /* M_PASTE */
 916                 balance_leaf_paste_right(tb, ih, body);
 917 }
 918 
 919 static void balance_leaf_new_nodes_insert(struct tree_balance *tb,
 920                                           struct item_head * const ih,
 921                                           const char * const body,
 922                                           struct item_head *insert_key,
 923                                           struct buffer_head **insert_ptr,
 924                                           int i)
 925 {
 926         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
 927         int n = B_NR_ITEMS(tbS0);
 928         struct buffer_info bi;
 929         int shift;
 930 
 931         /* new item or it part don't falls into S_new[i] */
 932         if (n - tb->snum[i] >= tb->item_pos) {
 933                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
 934                                 tb->snum[i], tb->sbytes[i], tb->S_new[i]);
 935                 return;
 936         }
 937 
 938         /* new item or it's part falls to first new node S_new[i] */
 939 
 940         /* part of new item falls into S_new[i] */
 941         if (tb->item_pos == n - tb->snum[i] + 1 && tb->sbytes[i] != -1) {
 942                 int old_key_comp, old_len, r_zeroes_number;
 943                 const char *r_body;
 944 
 945                 /* Move snum[i]-1 items from S[0] to S_new[i] */
 946                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i] - 1, -1,
 947                                 tb->S_new[i]);
 948 
 949                 /* Remember key component and item length */
 950                 old_key_comp = le_ih_k_offset(ih);
 951                 old_len = ih_item_len(ih);
 952 
 953                 /*
 954                  * Calculate key component and item length to insert
 955                  * into S_new[i]
 956                  */
 957                 shift = 0;
 958                 if (is_indirect_le_ih(ih))
 959                         shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
 960                 set_le_ih_k_offset(ih,
 961                                    le_ih_k_offset(ih) +
 962                                    ((old_len - tb->sbytes[i]) << shift));
 963 
 964                 put_ih_item_len(ih, tb->sbytes[i]);
 965 
 966                 /* Insert part of the item into S_new[i] before 0-th item */
 967                 buffer_info_init_bh(tb, &bi, tb->S_new[i]);
 968 
 969                 if ((old_len - tb->sbytes[i]) > tb->zeroes_num) {
 970                         r_zeroes_number = 0;
 971                         r_body = body + (old_len - tb->sbytes[i]) -
 972                                          tb->zeroes_num;
 973                 } else {
 974                         r_body = body;
 975                         r_zeroes_number = tb->zeroes_num - (old_len -
 976                                           tb->sbytes[i]);
 977                         tb->zeroes_num -= r_zeroes_number;
 978                 }
 979 
 980                 leaf_insert_into_buf(&bi, 0, ih, r_body, r_zeroes_number);
 981 
 982                 /*
 983                  * Calculate key component and item length to
 984                  * insert into S[i]
 985                  */
 986                 set_le_ih_k_offset(ih, old_key_comp);
 987                 put_ih_item_len(ih, old_len - tb->sbytes[i]);
 988                 tb->insert_size[0] -= tb->sbytes[i];
 989         } else {
 990                 /* whole new item falls into S_new[i] */
 991 
 992                 /*
 993                  * Shift snum[0] - 1 items to S_new[i]
 994                  * (sbytes[i] of split item)
 995                  */
 996                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
 997                                 tb->snum[i] - 1, tb->sbytes[i], tb->S_new[i]);
 998 
 999                 /* Insert new item into S_new[i] */
1000                 buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1001                 leaf_insert_into_buf(&bi, tb->item_pos - n + tb->snum[i] - 1,
1002                                      ih, body, tb->zeroes_num);
1003 
1004                 tb->zeroes_num = tb->insert_size[0] = 0;
1005         }
1006 }
1007 
1008 /* we append to directory item */
1009 static void balance_leaf_new_nodes_paste_dirent(struct tree_balance *tb,
1010                                          struct item_head * const ih,
1011                                          const char * const body,
1012                                          struct item_head *insert_key,
1013                                          struct buffer_head **insert_ptr,
1014                                          int i)
1015 {
1016         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1017         struct item_head *aux_ih = item_head(tbS0, tb->item_pos);
1018         int entry_count = ih_entry_count(aux_ih);
1019         struct buffer_info bi;
1020 
1021         if (entry_count - tb->sbytes[i] < tb->pos_in_item &&
1022             tb->pos_in_item <= entry_count) {
1023                 /* new directory entry falls into S_new[i] */
1024 
1025                 RFALSE(!tb->insert_size[0],
1026                        "PAP-12215: insert_size is already 0");
1027                 RFALSE(tb->sbytes[i] - 1 >= entry_count,
1028                        "PAP-12220: there are no so much entries (%d), only %d",
1029                        tb->sbytes[i] - 1, entry_count);
1030 
1031                 /*
1032                  * Shift snum[i]-1 items in whole.
1033                  * Shift sbytes[i] directory entries
1034                  * from directory item number snum[i]
1035                  */
1036                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i],
1037                                 tb->sbytes[i] - 1, tb->S_new[i]);
1038 
1039                 /*
1040                  * Paste given directory entry to
1041                  * directory item
1042                  */
1043                 buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1044                 leaf_paste_in_buffer(&bi, 0, tb->pos_in_item - entry_count +
1045                                      tb->sbytes[i] - 1, tb->insert_size[0],
1046                                      body, tb->zeroes_num);
1047 
1048                 /* paste new directory entry */
1049                 leaf_paste_entries(&bi, 0, tb->pos_in_item - entry_count +
1050                                    tb->sbytes[i] - 1, 1,
1051                                    (struct reiserfs_de_head *) body,
1052                                    body + DEH_SIZE, tb->insert_size[0]);
1053 
1054                 tb->insert_size[0] = 0;
1055                 tb->pos_in_item++;
1056         } else {
1057                 /* new directory entry doesn't fall into S_new[i] */
1058                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i],
1059                                 tb->sbytes[i], tb->S_new[i]);
1060         }
1061 
1062 }
1063 
1064 static void balance_leaf_new_nodes_paste_shift(struct tree_balance *tb,
1065                                          struct item_head * const ih,
1066                                          const char * const body,
1067                                          struct item_head *insert_key,
1068                                          struct buffer_head **insert_ptr,
1069                                          int i)
1070 {
1071         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1072         struct item_head *aux_ih = item_head(tbS0, tb->item_pos);
1073         int n_shift, n_rem, r_zeroes_number, shift;
1074         const char *r_body;
1075         struct item_head *tmp;
1076         struct buffer_info bi;
1077 
1078         RFALSE(ih, "PAP-12210: ih must be 0");
1079 
1080         if (is_direntry_le_ih(aux_ih)) {
1081                 balance_leaf_new_nodes_paste_dirent(tb, ih, body, insert_key,
1082                                                     insert_ptr, i);
1083                 return;
1084         }
1085 
1086         /* regular object */
1087 
1088 
1089         RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)) ||
1090                tb->insert_size[0] <= 0,
1091                "PAP-12225: item too short or insert_size <= 0");
1092 
1093         /*
1094          * Calculate number of bytes which must be shifted from appended item
1095          */
1096         n_shift = tb->sbytes[i] - tb->insert_size[0];
1097         if (n_shift < 0)
1098                 n_shift = 0;
1099         leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], n_shift,
1100                         tb->S_new[i]);
1101 
1102         /*
1103          * Calculate number of bytes which must remain in body after
1104          * append to S_new[i]
1105          */
1106         n_rem = tb->insert_size[0] - tb->sbytes[i];
1107         if (n_rem < 0)
1108                 n_rem = 0;
1109 
1110         /* Append part of body into S_new[0] */
1111         buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1112         if (n_rem > tb->zeroes_num) {
1113                 r_zeroes_number = 0;
1114                 r_body = body + n_rem - tb->zeroes_num;
1115         } else {
1116                 r_body = body;
1117                 r_zeroes_number = tb->zeroes_num - n_rem;
1118                 tb->zeroes_num -= r_zeroes_number;
1119         }
1120 
1121         leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem,
1122                              r_body, r_zeroes_number);
1123 
1124         tmp = item_head(tb->S_new[i], 0);
1125         shift = 0;
1126         if (is_indirect_le_ih(tmp)) {
1127                 set_ih_free_space(tmp, 0);
1128                 shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
1129         }
1130         add_le_ih_k_offset(tmp, n_rem << shift);
1131 
1132         tb->insert_size[0] = n_rem;
1133         if (!n_rem)
1134                 tb->pos_in_item++;
1135 }
1136 
1137 static void balance_leaf_new_nodes_paste_whole(struct tree_balance *tb,
1138                                                struct item_head * const ih,
1139                                                const char * const body,
1140                                                struct item_head *insert_key,
1141                                                struct buffer_head **insert_ptr,
1142                                                int i)
1143 
1144 {
1145         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1146         int n = B_NR_ITEMS(tbS0);
1147         int leaf_mi;
1148         struct item_head *pasted;
1149         struct buffer_info bi;
1150 
1151 #ifdef CONFIG_REISERFS_CHECK
1152         struct item_head *ih_check = item_head(tbS0, tb->item_pos);
1153 
1154         if (!is_direntry_le_ih(ih_check) &&
1155             (tb->pos_in_item != ih_item_len(ih_check) ||
1156             tb->insert_size[0] <= 0))
1157                 reiserfs_panic(tb->tb_sb,
1158                              "PAP-12235",
1159                              "pos_in_item must be equal to ih_item_len");
1160 #endif
1161 
1162         leaf_mi = leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i],
1163                                   tb->sbytes[i], tb->S_new[i]);
1164 
1165         RFALSE(leaf_mi,
1166                "PAP-12240: unexpected value returned by leaf_move_items (%d)",
1167                leaf_mi);
1168 
1169         /* paste into item */
1170         buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1171         leaf_paste_in_buffer(&bi, tb->item_pos - n + tb->snum[i],
1172                              tb->pos_in_item, tb->insert_size[0],
1173                              body, tb->zeroes_num);
1174 
1175         pasted = item_head(tb->S_new[i], tb->item_pos - n +
1176                            tb->snum[i]);
1177         if (is_direntry_le_ih(pasted))
1178                 leaf_paste_entries(&bi, tb->item_pos - n + tb->snum[i],
1179                                    tb->pos_in_item, 1,
1180                                    (struct reiserfs_de_head *)body,
1181                                    body + DEH_SIZE, tb->insert_size[0]);
1182 
1183         /* if we paste to indirect item update ih_free_space */
1184         if (is_indirect_le_ih(pasted))
1185                 set_ih_free_space(pasted, 0);
1186 
1187         tb->zeroes_num = tb->insert_size[0] = 0;
1188 
1189 }
1190 static void balance_leaf_new_nodes_paste(struct tree_balance *tb,
1191                                          struct item_head * const ih,
1192                                          const char * const body,
1193                                          struct item_head *insert_key,
1194                                          struct buffer_head **insert_ptr,
1195                                          int i)
1196 {
1197         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1198         int n = B_NR_ITEMS(tbS0);
1199 
1200         /* pasted item doesn't fall into S_new[i] */
1201         if (n - tb->snum[i] > tb->item_pos) {
1202                 leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
1203                                 tb->snum[i], tb->sbytes[i], tb->S_new[i]);
1204                 return;
1205         }
1206 
1207         /* pasted item or part if it falls to S_new[i] */
1208 
1209         if (tb->item_pos == n - tb->snum[i] && tb->sbytes[i] != -1)
1210                 /* we must shift part of the appended item */
1211                 balance_leaf_new_nodes_paste_shift(tb, ih, body, insert_key,
1212                                                    insert_ptr, i);
1213         else
1214                 /* item falls wholly into S_new[i] */
1215                 balance_leaf_new_nodes_paste_whole(tb, ih, body, insert_key,
1216                                                    insert_ptr, i);
1217 }
1218 
1219 /* Fill new nodes that appear in place of S[0] */
1220 static void balance_leaf_new_nodes(struct tree_balance *tb,
1221                                    struct item_head * const ih,
1222                                    const char * const body,
1223                                    struct item_head *insert_key,
1224                                    struct buffer_head **insert_ptr,
1225                                    int flag)
1226 {
1227         int i;
1228         for (i = tb->blknum[0] - 2; i >= 0; i--) {
1229                 BUG_ON(flag != M_INSERT && flag != M_PASTE);
1230 
1231                 RFALSE(!tb->snum[i],
1232                        "PAP-12200: snum[%d] == %d. Must be > 0", i,
1233                        tb->snum[i]);
1234 
1235                 /* here we shift from S to S_new nodes */
1236 
1237                 tb->S_new[i] = get_FEB(tb);
1238 
1239                 /* initialized block type and tree level */
1240                 set_blkh_level(B_BLK_HEAD(tb->S_new[i]), DISK_LEAF_NODE_LEVEL);
1241 
1242                 if (flag == M_INSERT)
1243                         balance_leaf_new_nodes_insert(tb, ih, body, insert_key,
1244                                                       insert_ptr, i);
1245                 else /* M_PASTE */
1246                         balance_leaf_new_nodes_paste(tb, ih, body, insert_key,
1247                                                      insert_ptr, i);
1248 
1249                 memcpy(insert_key + i, leaf_key(tb->S_new[i], 0), KEY_SIZE);
1250                 insert_ptr[i] = tb->S_new[i];
1251 
1252                 RFALSE(!buffer_journaled(tb->S_new[i])
1253                        || buffer_journal_dirty(tb->S_new[i])
1254                        || buffer_dirty(tb->S_new[i]),
1255                        "PAP-12247: S_new[%d] : (%b)",
1256                        i, tb->S_new[i]);
1257         }
1258 }
1259 
1260 static void balance_leaf_finish_node_insert(struct tree_balance *tb,
1261                                             struct item_head * const ih,
1262                                             const char * const body)
1263 {
1264         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1265         struct buffer_info bi;
1266         buffer_info_init_tbS0(tb, &bi);
1267         leaf_insert_into_buf(&bi, tb->item_pos, ih, body, tb->zeroes_num);
1268 
1269         /* If we insert the first key change the delimiting key */
1270         if (tb->item_pos == 0) {
1271                 if (tb->CFL[0]) /* can be 0 in reiserfsck */
1272                         replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0);
1273 
1274         }
1275 }
1276 
1277 static void balance_leaf_finish_node_paste_dirent(struct tree_balance *tb,
1278                                                   struct item_head * const ih,
1279                                                   const char * const body)
1280 {
1281         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1282         struct item_head *pasted = item_head(tbS0, tb->item_pos);
1283         struct buffer_info bi;
1284 
1285         if (tb->pos_in_item >= 0 && tb->pos_in_item <= ih_entry_count(pasted)) {
1286                 RFALSE(!tb->insert_size[0],
1287                        "PAP-12260: insert_size is 0 already");
1288 
1289                 /* prepare space */
1290                 buffer_info_init_tbS0(tb, &bi);
1291                 leaf_paste_in_buffer(&bi, tb->item_pos, tb->pos_in_item,
1292                                      tb->insert_size[0], body, tb->zeroes_num);
1293 
1294                 /* paste entry */
1295                 leaf_paste_entries(&bi, tb->item_pos, tb->pos_in_item, 1,
1296                                    (struct reiserfs_de_head *)body,
1297                                    body + DEH_SIZE, tb->insert_size[0]);
1298 
1299                 if (!tb->item_pos && !tb->pos_in_item) {
1300                         RFALSE(!tb->CFL[0] || !tb->L[0],
1301                                "PAP-12270: CFL[0]/L[0] must  be specified");
1302                         if (tb->CFL[0])
1303                                 replace_key(tb, tb->CFL[0], tb->lkey[0],
1304                                             tbS0, 0);
1305                 }
1306 
1307                 tb->insert_size[0] = 0;
1308         }
1309 }
1310 
1311 static void balance_leaf_finish_node_paste(struct tree_balance *tb,
1312                                            struct item_head * const ih,
1313                                            const char * const body)
1314 {
1315         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1316         struct buffer_info bi;
1317         struct item_head *pasted = item_head(tbS0, tb->item_pos);
1318 
1319         /* when directory, may be new entry already pasted */
1320         if (is_direntry_le_ih(pasted)) {
1321                 balance_leaf_finish_node_paste_dirent(tb, ih, body);
1322                 return;
1323         }
1324 
1325         /* regular object */
1326 
1327         if (tb->pos_in_item == ih_item_len(pasted)) {
1328                 RFALSE(tb->insert_size[0] <= 0,
1329                        "PAP-12275: insert size must not be %d",
1330                        tb->insert_size[0]);
1331                 buffer_info_init_tbS0(tb, &bi);
1332                 leaf_paste_in_buffer(&bi, tb->item_pos,
1333                                      tb->pos_in_item, tb->insert_size[0], body,
1334                                      tb->zeroes_num);
1335 
1336                 if (is_indirect_le_ih(pasted))
1337                         set_ih_free_space(pasted, 0);
1338 
1339                 tb->insert_size[0] = 0;
1340         }
1341 #ifdef CONFIG_REISERFS_CHECK
1342         else if (tb->insert_size[0]) {
1343                 print_cur_tb("12285");
1344                 reiserfs_panic(tb->tb_sb, "PAP-12285",
1345                     "insert_size must be 0 (%d)", tb->insert_size[0]);
1346         }
1347 #endif
1348 }
1349 
1350 /*
1351  * if the affected item was not wholly shifted then we
1352  * perform all necessary operations on that part or whole
1353  * of the affected item which remains in S
1354  */
1355 static void balance_leaf_finish_node(struct tree_balance *tb,
1356                                       struct item_head * const ih,
1357                                       const char * const body, int flag)
1358 {
1359         /* if we must insert or append into buffer S[0] */
1360         if (0 <= tb->item_pos && tb->item_pos < tb->s0num) {
1361                 if (flag == M_INSERT)
1362                         balance_leaf_finish_node_insert(tb, ih, body);
1363                 else /* M_PASTE */
1364                         balance_leaf_finish_node_paste(tb, ih, body);
1365         }
1366 }
1367 
1368 /**
1369  * balance_leaf - reiserfs tree balancing algorithm
1370  * @tb: tree balance state
1371  * @ih: item header of inserted item (little endian)
1372  * @body: body of inserted item or bytes to paste
1373  * @flag: i - insert, d - delete, c - cut, p - paste (see do_balance)
1374  * passed back:
1375  * @insert_key: key to insert new nodes
1376  * @insert_ptr: array of nodes to insert at the next level
1377  *
1378  * In our processing of one level we sometimes determine what must be
1379  * inserted into the next higher level.  This insertion consists of a
1380  * key or two keys and their corresponding pointers.
1381  */
1382 static int balance_leaf(struct tree_balance *tb, struct item_head *ih,
1383                         const char *body, int flag,
1384                         struct item_head *insert_key,
1385                         struct buffer_head **insert_ptr)
1386 {
1387         struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1388 
1389         PROC_INFO_INC(tb->tb_sb, balance_at[0]);
1390 
1391         /* Make balance in case insert_size[0] < 0 */
1392         if (tb->insert_size[0] < 0)
1393                 return balance_leaf_when_delete(tb, flag);
1394 
1395         tb->item_pos = PATH_LAST_POSITION(tb->tb_path),
1396         tb->pos_in_item = tb->tb_path->pos_in_item,
1397         tb->zeroes_num = 0;
1398         if (flag == M_INSERT && !body)
1399                 tb->zeroes_num = ih_item_len(ih);
1400 
1401         /*
1402          * for indirect item pos_in_item is measured in unformatted node
1403          * pointers. Recalculate to bytes
1404          */
1405         if (flag != M_INSERT
1406             && is_indirect_le_ih(item_head(tbS0, tb->item_pos)))
1407                 tb->pos_in_item *= UNFM_P_SIZE;
1408 
1409         body += balance_leaf_left(tb, ih, body, flag);
1410 
1411         /* tb->lnum[0] > 0 */
1412         /* Calculate new item position */
1413         tb->item_pos -= (tb->lnum[0] - ((tb->lbytes != -1) ? 1 : 0));
1414 
1415         balance_leaf_right(tb, ih, body, flag);
1416 
1417         /* tb->rnum[0] > 0 */
1418         RFALSE(tb->blknum[0] > 3,
1419                "PAP-12180: blknum can not be %d. It must be <= 3", tb->blknum[0]);
1420         RFALSE(tb->blknum[0] < 0,
1421                "PAP-12185: blknum can not be %d. It must be >= 0", tb->blknum[0]);
1422 
1423         /*
1424          * if while adding to a node we discover that it is possible to split
1425          * it in two, and merge the left part into the left neighbor and the
1426          * right part into the right neighbor, eliminating the node
1427          */
1428         if (tb->blknum[0] == 0) {       /* node S[0] is empty now */
1429 
1430                 RFALSE(!tb->lnum[0] || !tb->rnum[0],
1431                        "PAP-12190: lnum and rnum must not be zero");
1432                 /*
1433                  * if insertion was done before 0-th position in R[0], right
1434                  * delimiting key of the tb->L[0]'s and left delimiting key are
1435                  * not set correctly
1436                  */
1437                 if (tb->CFL[0]) {
1438                         if (!tb->CFR[0])
1439                                 reiserfs_panic(tb->tb_sb, "vs-12195",
1440                                                "CFR not initialized");
1441                         copy_key(internal_key(tb->CFL[0], tb->lkey[0]),
1442                                  internal_key(tb->CFR[0], tb->rkey[0]));
1443                         do_balance_mark_internal_dirty(tb, tb->CFL[0], 0);
1444                 }
1445 
1446                 reiserfs_invalidate_buffer(tb, tbS0);
1447                 return 0;
1448         }
1449 
1450         balance_leaf_new_nodes(tb, ih, body, insert_key, insert_ptr, flag);
1451 
1452         balance_leaf_finish_node(tb, ih, body, flag);
1453 
1454 #ifdef CONFIG_REISERFS_CHECK
1455         if (flag == M_PASTE && tb->insert_size[0]) {
1456                 print_cur_tb("12290");
1457                 reiserfs_panic(tb->tb_sb,
1458                                "PAP-12290", "insert_size is still not 0 (%d)",
1459                                tb->insert_size[0]);
1460         }
1461 #endif
1462 
1463         /* Leaf level of the tree is balanced (end of balance_leaf) */
1464         return 0;
1465 }
1466 
1467 /* Make empty node */
1468 void make_empty_node(struct buffer_info *bi)
1469 {
1470         struct block_head *blkh;
1471 
1472         RFALSE(bi->bi_bh == NULL, "PAP-12295: pointer to the buffer is NULL");
1473 
1474         blkh = B_BLK_HEAD(bi->bi_bh);
1475         set_blkh_nr_item(blkh, 0);
1476         set_blkh_free_space(blkh, MAX_CHILD_SIZE(bi->bi_bh));
1477 
1478         if (bi->bi_parent)
1479                 B_N_CHILD(bi->bi_parent, bi->bi_position)->dc_size = 0; /* Endian safe if 0 */
1480 }
1481 
1482 /* Get first empty buffer */
1483 struct buffer_head *get_FEB(struct tree_balance *tb)
1484 {
1485         int i;
1486         struct buffer_info bi;
1487 
1488         for (i = 0; i < MAX_FEB_SIZE; i++)
1489                 if (tb->FEB[i] != NULL)
1490                         break;
1491 
1492         if (i == MAX_FEB_SIZE)
1493                 reiserfs_panic(tb->tb_sb, "vs-12300", "FEB list is empty");
1494 
1495         buffer_info_init_bh(tb, &bi, tb->FEB[i]);
1496         make_empty_node(&bi);
1497         set_buffer_uptodate(tb->FEB[i]);
1498         tb->used[i] = tb->FEB[i];
1499         tb->FEB[i] = NULL;
1500 
1501         return tb->used[i];
1502 }
1503 
1504 /* This is now used because reiserfs_free_block has to be able to schedule. */
1505 static void store_thrown(struct tree_balance *tb, struct buffer_head *bh)
1506 {
1507         int i;
1508 
1509         if (buffer_dirty(bh))
1510                 reiserfs_warning(tb->tb_sb, "reiserfs-12320",
1511                                  "called with dirty buffer");
1512         for (i = 0; i < ARRAY_SIZE(tb->thrown); i++)
1513                 if (!tb->thrown[i]) {
1514                         tb->thrown[i] = bh;
1515                         get_bh(bh);     /* free_thrown puts this */
1516                         return;
1517                 }
1518         reiserfs_warning(tb->tb_sb, "reiserfs-12321",
1519                          "too many thrown buffers");
1520 }
1521 
1522 static void free_thrown(struct tree_balance *tb)
1523 {
1524         int i;
1525         b_blocknr_t blocknr;
1526         for (i = 0; i < ARRAY_SIZE(tb->thrown); i++) {
1527                 if (tb->thrown[i]) {
1528                         blocknr = tb->thrown[i]->b_blocknr;
1529                         if (buffer_dirty(tb->thrown[i]))
1530                                 reiserfs_warning(tb->tb_sb, "reiserfs-12322",
1531                                                  "called with dirty buffer %d",
1532                                                  blocknr);
1533                         brelse(tb->thrown[i]);  /* incremented in store_thrown */
1534                         reiserfs_free_block(tb->transaction_handle, NULL,
1535                                             blocknr, 0);
1536                 }
1537         }
1538 }
1539 
1540 void reiserfs_invalidate_buffer(struct tree_balance *tb, struct buffer_head *bh)
1541 {
1542         struct block_head *blkh;
1543         blkh = B_BLK_HEAD(bh);
1544         set_blkh_level(blkh, FREE_LEVEL);
1545         set_blkh_nr_item(blkh, 0);
1546 
1547         clear_buffer_dirty(bh);
1548         store_thrown(tb, bh);
1549 }
1550 
1551 /* Replace n_dest'th key in buffer dest by n_src'th key of buffer src.*/
1552 void replace_key(struct tree_balance *tb, struct buffer_head *dest, int n_dest,
1553                  struct buffer_head *src, int n_src)
1554 {
1555 
1556         RFALSE(dest == NULL || src == NULL,
1557                "vs-12305: source or destination buffer is 0 (src=%p, dest=%p)",
1558                src, dest);
1559         RFALSE(!B_IS_KEYS_LEVEL(dest),
1560                "vs-12310: invalid level (%z) for destination buffer. dest must be leaf",
1561                dest);
1562         RFALSE(n_dest < 0 || n_src < 0,
1563                "vs-12315: src(%d) or dest(%d) key number < 0", n_src, n_dest);
1564         RFALSE(n_dest >= B_NR_ITEMS(dest) || n_src >= B_NR_ITEMS(src),
1565                "vs-12320: src(%d(%d)) or dest(%d(%d)) key number is too big",
1566                n_src, B_NR_ITEMS(src), n_dest, B_NR_ITEMS(dest));
1567 
1568         if (B_IS_ITEMS_LEVEL(src))
1569                 /* source buffer contains leaf node */
1570                 memcpy(internal_key(dest, n_dest), item_head(src, n_src),
1571                        KEY_SIZE);
1572         else
1573                 memcpy(internal_key(dest, n_dest), internal_key(src, n_src),
1574                        KEY_SIZE);
1575 
1576         do_balance_mark_internal_dirty(tb, dest, 0);
1577 }
1578 
1579 int get_left_neighbor_position(struct tree_balance *tb, int h)
1580 {
1581         int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1);
1582 
1583         RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FL[h] == NULL,
1584                "vs-12325: FL[%d](%p) or F[%d](%p) does not exist",
1585                h, tb->FL[h], h, PATH_H_PPARENT(tb->tb_path, h));
1586 
1587         if (Sh_position == 0)
1588                 return B_NR_ITEMS(tb->FL[h]);
1589         else
1590                 return Sh_position - 1;
1591 }
1592 
1593 int get_right_neighbor_position(struct tree_balance *tb, int h)
1594 {
1595         int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1);
1596 
1597         RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FR[h] == NULL,
1598                "vs-12330: F[%d](%p) or FR[%d](%p) does not exist",
1599                h, PATH_H_PPARENT(tb->tb_path, h), h, tb->FR[h]);
1600 
1601         if (Sh_position == B_NR_ITEMS(PATH_H_PPARENT(tb->tb_path, h)))
1602                 return 0;
1603         else
1604                 return Sh_position + 1;
1605 }
1606 
1607 #ifdef CONFIG_REISERFS_CHECK
1608 
1609 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value);
1610 static void check_internal_node(struct super_block *s, struct buffer_head *bh,
1611                                 char *mes)
1612 {
1613         struct disk_child *dc;
1614         int i;
1615 
1616         RFALSE(!bh, "PAP-12336: bh == 0");
1617 
1618         if (!bh || !B_IS_IN_TREE(bh))
1619                 return;
1620 
1621         RFALSE(!buffer_dirty(bh) &&
1622                !(buffer_journaled(bh) || buffer_journal_dirty(bh)),
1623                "PAP-12337: buffer (%b) must be dirty", bh);
1624         dc = B_N_CHILD(bh, 0);
1625 
1626         for (i = 0; i <= B_NR_ITEMS(bh); i++, dc++) {
1627                 if (!is_reusable(s, dc_block_number(dc), 1)) {
1628                         print_cur_tb(mes);
1629                         reiserfs_panic(s, "PAP-12338",
1630                                        "invalid child pointer %y in %b",
1631                                        dc, bh);
1632                 }
1633         }
1634 }
1635 
1636 static int locked_or_not_in_tree(struct tree_balance *tb,
1637                                   struct buffer_head *bh, char *which)
1638 {
1639         if ((!buffer_journal_prepared(bh) && buffer_locked(bh)) ||
1640             !B_IS_IN_TREE(bh)) {
1641                 reiserfs_warning(tb->tb_sb, "vs-12339", "%s (%b)", which, bh);
1642                 return 1;
1643         }
1644         return 0;
1645 }
1646 
1647 static int check_before_balancing(struct tree_balance *tb)
1648 {
1649         int retval = 0;
1650 
1651         if (REISERFS_SB(tb->tb_sb)->cur_tb) {
1652                 reiserfs_panic(tb->tb_sb, "vs-12335", "suspect that schedule "
1653                                "occurred based on cur_tb not being null at "
1654                                "this point in code. do_balance cannot properly "
1655                                "handle concurrent tree accesses on a same "
1656                                "mount point.");
1657         }
1658 
1659         /*
1660          * double check that buffers that we will modify are unlocked.
1661          * (fix_nodes should already have prepped all of these for us).
1662          */
1663         if (tb->lnum[0]) {
1664                 retval |= locked_or_not_in_tree(tb, tb->L[0], "L[0]");
1665                 retval |= locked_or_not_in_tree(tb, tb->FL[0], "FL[0]");
1666                 retval |= locked_or_not_in_tree(tb, tb->CFL[0], "CFL[0]");
1667                 check_leaf(tb->L[0]);
1668         }
1669         if (tb->rnum[0]) {
1670                 retval |= locked_or_not_in_tree(tb, tb->R[0], "R[0]");
1671                 retval |= locked_or_not_in_tree(tb, tb->FR[0], "FR[0]");
1672                 retval |= locked_or_not_in_tree(tb, tb->CFR[0], "CFR[0]");
1673                 check_leaf(tb->R[0]);
1674         }
1675         retval |= locked_or_not_in_tree(tb, PATH_PLAST_BUFFER(tb->tb_path),
1676                                         "S[0]");
1677         check_leaf(PATH_PLAST_BUFFER(tb->tb_path));
1678 
1679         return retval;
1680 }
1681 
1682 static void check_after_balance_leaf(struct tree_balance *tb)
1683 {
1684         if (tb->lnum[0]) {
1685                 if (B_FREE_SPACE(tb->L[0]) !=
1686                     MAX_CHILD_SIZE(tb->L[0]) -
1687                     dc_size(B_N_CHILD
1688                             (tb->FL[0], get_left_neighbor_position(tb, 0)))) {
1689                         print_cur_tb("12221");
1690                         reiserfs_panic(tb->tb_sb, "PAP-12355",
1691                                        "shift to left was incorrect");
1692                 }
1693         }
1694         if (tb->rnum[0]) {
1695                 if (B_FREE_SPACE(tb->R[0]) !=
1696                     MAX_CHILD_SIZE(tb->R[0]) -
1697                     dc_size(B_N_CHILD
1698                             (tb->FR[0], get_right_neighbor_position(tb, 0)))) {
1699                         print_cur_tb("12222");
1700                         reiserfs_panic(tb->tb_sb, "PAP-12360",
1701                                        "shift to right was incorrect");
1702                 }
1703         }
1704         if (PATH_H_PBUFFER(tb->tb_path, 1) &&
1705             (B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0)) !=
1706              (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) -
1707               dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1),
1708                                 PATH_H_POSITION(tb->tb_path, 1)))))) {
1709                 int left = B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0));
1710                 int right = (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) -
1711                              dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1),
1712                                                PATH_H_POSITION(tb->tb_path,
1713                                                                1))));
1714                 print_cur_tb("12223");
1715                 reiserfs_warning(tb->tb_sb, "reiserfs-12363",
1716                                  "B_FREE_SPACE (PATH_H_PBUFFER(tb->tb_path,0)) = %d; "
1717                                  "MAX_CHILD_SIZE (%d) - dc_size( %y, %d ) [%d] = %d",
1718                                  left,
1719                                  MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)),
1720                                  PATH_H_PBUFFER(tb->tb_path, 1),
1721                                  PATH_H_POSITION(tb->tb_path, 1),
1722                                  dc_size(B_N_CHILD
1723                                          (PATH_H_PBUFFER(tb->tb_path, 1),
1724                                           PATH_H_POSITION(tb->tb_path, 1))),
1725                                  right);
1726                 reiserfs_panic(tb->tb_sb, "PAP-12365", "S is incorrect");
1727         }
1728 }
1729 
1730 static void check_leaf_level(struct tree_balance *tb)
1731 {
1732         check_leaf(tb->L[0]);
1733         check_leaf(tb->R[0]);
1734         check_leaf(PATH_PLAST_BUFFER(tb->tb_path));
1735 }
1736 
1737 static void check_internal_levels(struct tree_balance *tb)
1738 {
1739         int h;
1740 
1741         /* check all internal nodes */
1742         for (h = 1; tb->insert_size[h]; h++) {
1743                 check_internal_node(tb->tb_sb, PATH_H_PBUFFER(tb->tb_path, h),
1744                                     "BAD BUFFER ON PATH");
1745                 if (tb->lnum[h])
1746                         check_internal_node(tb->tb_sb, tb->L[h], "BAD L");
1747                 if (tb->rnum[h])
1748                         check_internal_node(tb->tb_sb, tb->R[h], "BAD R");
1749         }
1750 
1751 }
1752 
1753 #endif
1754 
1755 /*
1756  * Now we have all of the buffers that must be used in balancing of
1757  * the tree.  We rely on the assumption that schedule() will not occur
1758  * while do_balance works. ( Only interrupt handlers are acceptable.)
1759  * We balance the tree according to the analysis made before this,
1760  * using buffers already obtained.  For SMP support it will someday be
1761  * necessary to add ordered locking of tb.
1762  */
1763 
1764 /*
1765  * Some interesting rules of balancing:
1766  * we delete a maximum of two nodes per level per balancing: we never
1767  * delete R, when we delete two of three nodes L, S, R then we move
1768  * them into R.
1769  *
1770  * we only delete L if we are deleting two nodes, if we delete only
1771  * one node we delete S
1772  *
1773  * if we shift leaves then we shift as much as we can: this is a
1774  * deliberate policy of extremism in node packing which results in
1775  * higher average utilization after repeated random balance operations
1776  * at the cost of more memory copies and more balancing as a result of
1777  * small insertions to full nodes.
1778  *
1779  * if we shift internal nodes we try to evenly balance the node
1780  * utilization, with consequent less balancing at the cost of lower
1781  * utilization.
1782  *
1783  * one could argue that the policy for directories in leaves should be
1784  * that of internal nodes, but we will wait until another day to
1785  * evaluate this....  It would be nice to someday measure and prove
1786  * these assumptions as to what is optimal....
1787  */
1788 
1789 static inline void do_balance_starts(struct tree_balance *tb)
1790 {
1791         /* use print_cur_tb() to see initial state of struct tree_balance */
1792 
1793         /* store_print_tb (tb); */
1794 
1795         /* do not delete, just comment it out */
1796         /*
1797         print_tb(flag, PATH_LAST_POSITION(tb->tb_path),
1798                  tb->tb_path->pos_in_item, tb, "check");
1799         */
1800         RFALSE(check_before_balancing(tb), "PAP-12340: locked buffers in TB");
1801 #ifdef CONFIG_REISERFS_CHECK
1802         REISERFS_SB(tb->tb_sb)->cur_tb = tb;
1803 #endif
1804 }
1805 
1806 static inline void do_balance_completed(struct tree_balance *tb)
1807 {
1808 
1809 #ifdef CONFIG_REISERFS_CHECK
1810         check_leaf_level(tb);
1811         check_internal_levels(tb);
1812         REISERFS_SB(tb->tb_sb)->cur_tb = NULL;
1813 #endif
1814 
1815         /*
1816          * reiserfs_free_block is no longer schedule safe.  So, we need to
1817          * put the buffers we want freed on the thrown list during do_balance,
1818          * and then free them now
1819          */
1820 
1821         REISERFS_SB(tb->tb_sb)->s_do_balance++;
1822 
1823         /* release all nodes hold to perform the balancing */
1824         unfix_nodes(tb);
1825 
1826         free_thrown(tb);
1827 }
1828 
1829 /*
1830  * do_balance - balance the tree
1831  *
1832  * @tb: tree_balance structure
1833  * @ih: item header of inserted item
1834  * @body: body of inserted item or bytes to paste
1835  * @flag: 'i' - insert, 'd' - delete, 'c' - cut, 'p' paste
1836  *
1837  * Cut means delete part of an item (includes removing an entry from a
1838  * directory).
1839  *
1840  * Delete means delete whole item.
1841  *
1842  * Insert means add a new item into the tree.
1843  *
1844  * Paste means to append to the end of an existing file or to
1845  * insert a directory entry.
1846  */
1847 void do_balance(struct tree_balance *tb, struct item_head *ih,
1848                 const char *body, int flag)
1849 {
1850         int child_pos;          /* position of a child node in its parent */
1851         int h;                  /* level of the tree being processed */
1852 
1853         /*
1854          * in our processing of one level we sometimes determine what
1855          * must be inserted into the next higher level.  This insertion
1856          * consists of a key or two keys and their corresponding
1857          * pointers
1858          */
1859         struct item_head insert_key[2];
1860 
1861         /* inserted node-ptrs for the next level */
1862         struct buffer_head *insert_ptr[2];
1863 
1864         tb->tb_mode = flag;
1865         tb->need_balance_dirty = 0;
1866 
1867         if (FILESYSTEM_CHANGED_TB(tb)) {
1868                 reiserfs_panic(tb->tb_sb, "clm-6000", "fs generation has "
1869                                "changed");
1870         }
1871         /* if we have no real work to do  */
1872         if (!tb->insert_size[0]) {
1873                 reiserfs_warning(tb->tb_sb, "PAP-12350",
1874                                  "insert_size == 0, mode == %c", flag);
1875                 unfix_nodes(tb);
1876                 return;
1877         }
1878 
1879         atomic_inc(&fs_generation(tb->tb_sb));
1880         do_balance_starts(tb);
1881 
1882         /*
1883          * balance_leaf returns 0 except if combining L R and S into
1884          * one node.  see balance_internal() for explanation of this
1885          * line of code.
1886          */
1887         child_pos = PATH_H_B_ITEM_ORDER(tb->tb_path, 0) +
1888             balance_leaf(tb, ih, body, flag, insert_key, insert_ptr);
1889 
1890 #ifdef CONFIG_REISERFS_CHECK
1891         check_after_balance_leaf(tb);
1892 #endif
1893 
1894         /* Balance internal level of the tree. */
1895         for (h = 1; h < MAX_HEIGHT && tb->insert_size[h]; h++)
1896                 child_pos = balance_internal(tb, h, child_pos, insert_key,
1897                                              insert_ptr);
1898 
1899         do_balance_completed(tb);
1900 }
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root/fs/reiserfs/do_balan.c

DEFINITIONS
