ClabureDB: Classified Bug-Reports Database

   /*
    * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
    */
   
   #include <asm/uaccess.h>
   #include <linux/string.h>
   #include <linux/time.h>
   #include <linux/reiserfs_fs.h>
   #include <linux/buffer_head.h>
  
  /* this is one and only function that is used outside (do_balance.c) */
  int balance_internal(struct tree_balance *,
                       int, int, struct item_head *, struct buffer_head **);
  
  /* modes of internal_shift_left, internal_shift_right and internal_insert_childs */
  #define INTERNAL_SHIFT_FROM_S_TO_L 0
  #define INTERNAL_SHIFT_FROM_R_TO_S 1
  #define INTERNAL_SHIFT_FROM_L_TO_S 2
  #define INTERNAL_SHIFT_FROM_S_TO_R 3
  #define INTERNAL_INSERT_TO_S 4
  #define INTERNAL_INSERT_TO_L 5
  #define INTERNAL_INSERT_TO_R 6
  
  static void internal_define_dest_src_infos(int shift_mode,
                                             struct tree_balance *tb,
                                             int h,
                                             struct buffer_info *dest_bi,
                                             struct buffer_info *src_bi,
                                             int *d_key, struct buffer_head **cf)
  {
          memset(dest_bi, 0, sizeof(struct buffer_info));
          memset(src_bi, 0, sizeof(struct buffer_info));
          /* define dest, src, dest parent, dest position */
          switch (shift_mode) {
          case INTERNAL_SHIFT_FROM_S_TO_L:        /* used in internal_shift_left */
                  src_bi->tb = tb;
                  src_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
                  src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
                  src_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
                  dest_bi->tb = tb;
                  dest_bi->bi_bh = tb->L[h];
                  dest_bi->bi_parent = tb->FL[h];
                  dest_bi->bi_position = get_left_neighbor_position(tb, h);
                  *d_key = tb->lkey[h];
                  *cf = tb->CFL[h];
                  break;
          case INTERNAL_SHIFT_FROM_L_TO_S:
                  src_bi->tb = tb;
                  src_bi->bi_bh = tb->L[h];
                  src_bi->bi_parent = tb->FL[h];
                  src_bi->bi_position = get_left_neighbor_position(tb, h);
                  dest_bi->tb = tb;
                  dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
                  dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
                  dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);        /* dest position is analog of dest->b_item_order */
                  *d_key = tb->lkey[h];
                  *cf = tb->CFL[h];
                  break;
  
          case INTERNAL_SHIFT_FROM_R_TO_S:        /* used in internal_shift_left */
                  src_bi->tb = tb;
                  src_bi->bi_bh = tb->R[h];
                  src_bi->bi_parent = tb->FR[h];
                  src_bi->bi_position = get_right_neighbor_position(tb, h);
                  dest_bi->tb = tb;
                  dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
                  dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
                  dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
                  *d_key = tb->rkey[h];
                  *cf = tb->CFR[h];
                  break;
  
          case INTERNAL_SHIFT_FROM_S_TO_R:
                  src_bi->tb = tb;
                  src_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
                  src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
                  src_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
                  dest_bi->tb = tb;
                  dest_bi->bi_bh = tb->R[h];
                  dest_bi->bi_parent = tb->FR[h];
                  dest_bi->bi_position = get_right_neighbor_position(tb, h);
                  *d_key = tb->rkey[h];
                  *cf = tb->CFR[h];
                  break;
  
          case INTERNAL_INSERT_TO_L:
                  dest_bi->tb = tb;
                  dest_bi->bi_bh = tb->L[h];
                  dest_bi->bi_parent = tb->FL[h];
                  dest_bi->bi_position = get_left_neighbor_position(tb, h);
                  break;
  
          case INTERNAL_INSERT_TO_S:
                  dest_bi->tb = tb;
                  dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
                  dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
                  dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
                  break;
  
         case INTERNAL_INSERT_TO_R:
                 dest_bi->tb = tb;
                 dest_bi->bi_bh = tb->R[h];
                 dest_bi->bi_parent = tb->FR[h];
                 dest_bi->bi_position = get_right_neighbor_position(tb, h);
                 break;
 
         default:
                 reiserfs_panic(tb->tb_sb,
                                "internal_define_dest_src_infos: shift type is unknown (%d)",
                                shift_mode);
         }
 }
 
 /* Insert count node pointers into buffer cur before position to + 1.
  * Insert count items into buffer cur before position to.
  * Items and node pointers are specified by inserted and bh respectively.
  */
 static void internal_insert_childs(struct buffer_info *cur_bi,
                                    int to, int count,
                                    struct item_head *inserted,
                                    struct buffer_head **bh)
 {
         struct buffer_head *cur = cur_bi->bi_bh;
         struct block_head *blkh;
         int nr;
         struct reiserfs_key *ih;
         struct disk_child new_dc[2];
         struct disk_child *dc;
         int i;
 
         if (count <= 0)
                 return;
 
         blkh = B_BLK_HEAD(cur);
         nr = blkh_nr_item(blkh);
 
         RFALSE(count > 2, "too many children (%d) are to be inserted", count);
         RFALSE(B_FREE_SPACE(cur) < count * (KEY_SIZE + DC_SIZE),
                "no enough free space (%d), needed %d bytes",
                B_FREE_SPACE(cur), count * (KEY_SIZE + DC_SIZE));
 
         /* prepare space for count disk_child */
         dc = B_N_CHILD(cur, to + 1);
 
         memmove(dc + count, dc, (nr + 1 - (to + 1)) * DC_SIZE);
 
         /* copy to_be_insert disk children */
         for (i = 0; i < count; i++) {
                 put_dc_size(&(new_dc[i]),
                             MAX_CHILD_SIZE(bh[i]) - B_FREE_SPACE(bh[i]));
                 put_dc_block_number(&(new_dc[i]), bh[i]->b_blocknr);
         }
         memcpy(dc, new_dc, DC_SIZE * count);
 
         /* prepare space for count items  */
         ih = B_N_PDELIM_KEY(cur, ((to == -1) ? 0 : to));
 
         memmove(ih + count, ih,
                 (nr - to) * KEY_SIZE + (nr + 1 + count) * DC_SIZE);
 
         /* copy item headers (keys) */
         memcpy(ih, inserted, KEY_SIZE);
         if (count > 1)
                 memcpy(ih + 1, inserted + 1, KEY_SIZE);
 
         /* sizes, item number */
         set_blkh_nr_item(blkh, blkh_nr_item(blkh) + count);
         set_blkh_free_space(blkh,
                             blkh_free_space(blkh) - count * (DC_SIZE +
                                                              KEY_SIZE));
 
         do_balance_mark_internal_dirty(cur_bi->tb, cur, 0);
 
         /*&&&&&&&&&&&&&&&&&&&&&&&& */
         check_internal(cur);
         /*&&&&&&&&&&&&&&&&&&&&&&&& */
 
         if (cur_bi->bi_parent) {
                 struct disk_child *t_dc =
                     B_N_CHILD(cur_bi->bi_parent, cur_bi->bi_position);
                 put_dc_size(t_dc,
                             dc_size(t_dc) + (count * (DC_SIZE + KEY_SIZE)));
                 do_balance_mark_internal_dirty(cur_bi->tb, cur_bi->bi_parent,
                                                0);
 
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
                 check_internal(cur_bi->bi_parent);
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
         }
 
 }
 
 /* Delete del_num items and node pointers from buffer cur starting from *
  * the first_i'th item and first_p'th pointers respectively.                */
 static void internal_delete_pointers_items(struct buffer_info *cur_bi,
                                            int first_p,
                                            int first_i, int del_num)
 {
         struct buffer_head *cur = cur_bi->bi_bh;
         int nr;
         struct block_head *blkh;
         struct reiserfs_key *key;
         struct disk_child *dc;
 
         RFALSE(cur == NULL, "buffer is 0");
         RFALSE(del_num < 0,
                "negative number of items (%d) can not be deleted", del_num);
         RFALSE(first_p < 0 || first_p + del_num > B_NR_ITEMS(cur) + 1
                || first_i < 0,
                "first pointer order (%d) < 0 or "
                "no so many pointers (%d), only (%d) or "
                "first key order %d < 0", first_p, first_p + del_num,
                B_NR_ITEMS(cur) + 1, first_i);
         if (del_num == 0)
                 return;
 
         blkh = B_BLK_HEAD(cur);
         nr = blkh_nr_item(blkh);
 
         if (first_p == 0 && del_num == nr + 1) {
                 RFALSE(first_i != 0,
                        "1st deleted key must have order 0, not %d", first_i);
                 make_empty_node(cur_bi);
                 return;
         }
 
         RFALSE(first_i + del_num > B_NR_ITEMS(cur),
                "first_i = %d del_num = %d "
                "no so many keys (%d) in the node (%b)(%z)",
                first_i, del_num, first_i + del_num, cur, cur);
 
         /* deleting */
         dc = B_N_CHILD(cur, first_p);
 
         memmove(dc, dc + del_num, (nr + 1 - first_p - del_num) * DC_SIZE);
         key = B_N_PDELIM_KEY(cur, first_i);
         memmove(key, key + del_num,
                 (nr - first_i - del_num) * KEY_SIZE + (nr + 1 -
                                                        del_num) * DC_SIZE);
 
         /* sizes, item number */
         set_blkh_nr_item(blkh, blkh_nr_item(blkh) - del_num);
         set_blkh_free_space(blkh,
                             blkh_free_space(blkh) +
                             (del_num * (KEY_SIZE + DC_SIZE)));
 
         do_balance_mark_internal_dirty(cur_bi->tb, cur, 0);
         /*&&&&&&&&&&&&&&&&&&&&&&& */
         check_internal(cur);
         /*&&&&&&&&&&&&&&&&&&&&&&& */
 
         if (cur_bi->bi_parent) {
                 struct disk_child *t_dc;
                 t_dc = B_N_CHILD(cur_bi->bi_parent, cur_bi->bi_position);
                 put_dc_size(t_dc,
                             dc_size(t_dc) - (del_num * (KEY_SIZE + DC_SIZE)));
 
                 do_balance_mark_internal_dirty(cur_bi->tb, cur_bi->bi_parent,
                                                0);
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
                 check_internal(cur_bi->bi_parent);
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
         }
 }
 
 /* delete n node pointers and items starting from given position */
 static void internal_delete_childs(struct buffer_info *cur_bi, int from, int n)
 {
         int i_from;
 
         i_from = (from == 0) ? from : from - 1;
 
         /* delete n pointers starting from `from' position in CUR;
            delete n keys starting from 'i_from' position in CUR;
          */
         internal_delete_pointers_items(cur_bi, from, i_from, n);
 }
 
 /* copy cpy_num node pointers and cpy_num - 1 items from buffer src to buffer dest
 * last_first == FIRST_TO_LAST means, that we copy first items from src to tail of dest
  * last_first == LAST_TO_FIRST means, that we copy last items from src to head of dest 
  */
 static void internal_copy_pointers_items(struct buffer_info *dest_bi,
                                          struct buffer_head *src,
                                          int last_first, int cpy_num)
 {
         /* ATTENTION! Number of node pointers in DEST is equal to number of items in DEST *
          * as delimiting key have already inserted to buffer dest.*/
         struct buffer_head *dest = dest_bi->bi_bh;
         int nr_dest, nr_src;
         int dest_order, src_order;
         struct block_head *blkh;
         struct reiserfs_key *key;
         struct disk_child *dc;
 
         nr_src = B_NR_ITEMS(src);
 
         RFALSE(dest == NULL || src == NULL,
                "src (%p) or dest (%p) buffer is 0", src, dest);
         RFALSE(last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST,
                "invalid last_first parameter (%d)", last_first);
         RFALSE(nr_src < cpy_num - 1,
                "no so many items (%d) in src (%d)", cpy_num, nr_src);
         RFALSE(cpy_num < 0, "cpy_num less than 0 (%d)", cpy_num);
         RFALSE(cpy_num - 1 + B_NR_ITEMS(dest) > (int)MAX_NR_KEY(dest),
                "cpy_num (%d) + item number in dest (%d) can not be > MAX_NR_KEY(%d)",
                cpy_num, B_NR_ITEMS(dest), MAX_NR_KEY(dest));
 
         if (cpy_num == 0)
                 return;
 
         /* coping */
         blkh = B_BLK_HEAD(dest);
         nr_dest = blkh_nr_item(blkh);
 
         /*dest_order = (last_first == LAST_TO_FIRST) ? 0 : nr_dest; */
         /*src_order = (last_first == LAST_TO_FIRST) ? (nr_src - cpy_num + 1) : 0; */
         (last_first == LAST_TO_FIRST) ? (dest_order = 0, src_order =
                                          nr_src - cpy_num + 1) : (dest_order =
                                                                   nr_dest,
                                                                   src_order =
                                                                   0);
 
         /* prepare space for cpy_num pointers */
         dc = B_N_CHILD(dest, dest_order);
 
         memmove(dc + cpy_num, dc, (nr_dest - dest_order) * DC_SIZE);
 
         /* insert pointers */
         memcpy(dc, B_N_CHILD(src, src_order), DC_SIZE * cpy_num);
 
         /* prepare space for cpy_num - 1 item headers */
         key = B_N_PDELIM_KEY(dest, dest_order);
         memmove(key + cpy_num - 1, key,
                 KEY_SIZE * (nr_dest - dest_order) + DC_SIZE * (nr_dest +
                                                                cpy_num));
 
         /* insert headers */
         memcpy(key, B_N_PDELIM_KEY(src, src_order), KEY_SIZE * (cpy_num - 1));
 
         /* sizes, item number */
         set_blkh_nr_item(blkh, blkh_nr_item(blkh) + (cpy_num - 1));
         set_blkh_free_space(blkh,
                             blkh_free_space(blkh) - (KEY_SIZE * (cpy_num - 1) +
                                                      DC_SIZE * cpy_num));
 
         do_balance_mark_internal_dirty(dest_bi->tb, dest, 0);
 
         /*&&&&&&&&&&&&&&&&&&&&&&&& */
         check_internal(dest);
         /*&&&&&&&&&&&&&&&&&&&&&&&& */
 
         if (dest_bi->bi_parent) {
                 struct disk_child *t_dc;
                 t_dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
                 put_dc_size(t_dc,
                             dc_size(t_dc) + (KEY_SIZE * (cpy_num - 1) +
                                              DC_SIZE * cpy_num));
 
                 do_balance_mark_internal_dirty(dest_bi->tb, dest_bi->bi_parent,
                                                0);
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
                 check_internal(dest_bi->bi_parent);
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
         }
 
 }
 
 /* Copy cpy_num node pointers and cpy_num - 1 items from buffer src to buffer dest.
  * Delete cpy_num - del_par items and node pointers from buffer src.
  * last_first == FIRST_TO_LAST means, that we copy/delete first items from src.
  * last_first == LAST_TO_FIRST means, that we copy/delete last items from src.
  */
 static void internal_move_pointers_items(struct buffer_info *dest_bi,
                                          struct buffer_info *src_bi,
                                          int last_first, int cpy_num,
                                          int del_par)
 {
         int first_pointer;
         int first_item;
 
         internal_copy_pointers_items(dest_bi, src_bi->bi_bh, last_first,
                                      cpy_num);
 
         if (last_first == FIRST_TO_LAST) {        /* shift_left occurs */
                 first_pointer = 0;
                 first_item = 0;
                 /* delete cpy_num - del_par pointers and keys starting for pointers with first_pointer, 
                    for key - with first_item */
                 internal_delete_pointers_items(src_bi, first_pointer,
                                                first_item, cpy_num - del_par);
         } else {                /* shift_right occurs */
                 int i, j;
 
                 i = (cpy_num - del_par ==
                      (j =
                       B_NR_ITEMS(src_bi->bi_bh)) + 1) ? 0 : j - cpy_num +
                     del_par;
 
                 internal_delete_pointers_items(src_bi,
                                                j + 1 - cpy_num + del_par, i,
                                                cpy_num - del_par);
         }
 }
 
 /* Insert n_src'th key of buffer src before n_dest'th key of buffer dest. */
 static void internal_insert_key(struct buffer_info *dest_bi, int dest_position_before,        /* insert key before key with n_dest number */
                                 struct buffer_head *src, int src_position)
 {
         struct buffer_head *dest = dest_bi->bi_bh;
         int nr;
         struct block_head *blkh;
         struct reiserfs_key *key;
 
         RFALSE(dest == NULL || src == NULL,
                "source(%p) or dest(%p) buffer is 0", src, dest);
         RFALSE(dest_position_before < 0 || src_position < 0,
                "source(%d) or dest(%d) key number less than 0",
                src_position, dest_position_before);
         RFALSE(dest_position_before > B_NR_ITEMS(dest) ||
                src_position >= B_NR_ITEMS(src),
                "invalid position in dest (%d (key number %d)) or in src (%d (key number %d))",
                dest_position_before, B_NR_ITEMS(dest),
                src_position, B_NR_ITEMS(src));
         RFALSE(B_FREE_SPACE(dest) < KEY_SIZE,
                "no enough free space (%d) in dest buffer", B_FREE_SPACE(dest));
 
         blkh = B_BLK_HEAD(dest);
         nr = blkh_nr_item(blkh);
 
         /* prepare space for inserting key */
         key = B_N_PDELIM_KEY(dest, dest_position_before);
         memmove(key + 1, key,
                 (nr - dest_position_before) * KEY_SIZE + (nr + 1) * DC_SIZE);
 
         /* insert key */
         memcpy(key, B_N_PDELIM_KEY(src, src_position), KEY_SIZE);
 
         /* Change dirt, free space, item number fields. */
 
         set_blkh_nr_item(blkh, blkh_nr_item(blkh) + 1);
         set_blkh_free_space(blkh, blkh_free_space(blkh) - KEY_SIZE);
 
         do_balance_mark_internal_dirty(dest_bi->tb, dest, 0);
 
         if (dest_bi->bi_parent) {
                 struct disk_child *t_dc;
                 t_dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
                 put_dc_size(t_dc, dc_size(t_dc) + KEY_SIZE);
 
                 do_balance_mark_internal_dirty(dest_bi->tb, dest_bi->bi_parent,
                                                0);
         }
 }
 
 /* Insert d_key'th (delimiting) key from buffer cfl to tail of dest. 
  * Copy pointer_amount node pointers and pointer_amount - 1 items from buffer src to buffer dest.
  * Replace  d_key'th key in buffer cfl.
  * Delete pointer_amount items and node pointers from buffer src.
  */
 /* this can be invoked both to shift from S to L and from R to S */
 static void internal_shift_left(int mode,        /* INTERNAL_FROM_S_TO_L | INTERNAL_FROM_R_TO_S */
                                 struct tree_balance *tb,
                                 int h, int pointer_amount)
 {
         struct buffer_info dest_bi, src_bi;
         struct buffer_head *cf;
         int d_key_position;
 
         internal_define_dest_src_infos(mode, tb, h, &dest_bi, &src_bi,
                                        &d_key_position, &cf);
 
         /*printk("pointer_amount = %d\n",pointer_amount); */
 
         if (pointer_amount) {
                 /* insert delimiting key from common father of dest and src to node dest into position B_NR_ITEM(dest) */
                 internal_insert_key(&dest_bi, B_NR_ITEMS(dest_bi.bi_bh), cf,
                                     d_key_position);
 
                 if (B_NR_ITEMS(src_bi.bi_bh) == pointer_amount - 1) {
                         if (src_bi.bi_position /*src->b_item_order */  == 0)
                                 replace_key(tb, cf, d_key_position,
                                             src_bi.
                                             bi_parent /*src->b_parent */ , 0);
                 } else
                         replace_key(tb, cf, d_key_position, src_bi.bi_bh,
                                     pointer_amount - 1);
         }
         /* last parameter is del_parameter */
         internal_move_pointers_items(&dest_bi, &src_bi, FIRST_TO_LAST,
                                      pointer_amount, 0);
 
 }
 
 /* Insert delimiting key to L[h].
  * Copy n node pointers and n - 1 items from buffer S[h] to L[h].
  * Delete n - 1 items and node pointers from buffer S[h].
  */
 /* it always shifts from S[h] to L[h] */
 static void internal_shift1_left(struct tree_balance *tb,
                                  int h, int pointer_amount)
 {
         struct buffer_info dest_bi, src_bi;
         struct buffer_head *cf;
         int d_key_position;
 
         internal_define_dest_src_infos(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
                                        &dest_bi, &src_bi, &d_key_position, &cf);
 
         if (pointer_amount > 0)        /* insert lkey[h]-th key  from CFL[h] to left neighbor L[h] */
                 internal_insert_key(&dest_bi, B_NR_ITEMS(dest_bi.bi_bh), cf,
                                     d_key_position);
         /*            internal_insert_key (tb->L[h], B_NR_ITEM(tb->L[h]), tb->CFL[h], tb->lkey[h]); */
 
         /* last parameter is del_parameter */
         internal_move_pointers_items(&dest_bi, &src_bi, FIRST_TO_LAST,
                                      pointer_amount, 1);
         /*    internal_move_pointers_items (tb->L[h], tb->S[h], FIRST_TO_LAST, pointer_amount, 1); */
 }
 
 /* Insert d_key'th (delimiting) key from buffer cfr to head of dest. 
  * Copy n node pointers and n - 1 items from buffer src to buffer dest.
  * Replace  d_key'th key in buffer cfr.
  * Delete n items and node pointers from buffer src.
  */
 static void internal_shift_right(int mode,        /* INTERNAL_FROM_S_TO_R | INTERNAL_FROM_L_TO_S */
                                  struct tree_balance *tb,
                                  int h, int pointer_amount)
 {
         struct buffer_info dest_bi, src_bi;
         struct buffer_head *cf;
         int d_key_position;
         int nr;
 
         internal_define_dest_src_infos(mode, tb, h, &dest_bi, &src_bi,
                                        &d_key_position, &cf);
 
         nr = B_NR_ITEMS(src_bi.bi_bh);
 
         if (pointer_amount > 0) {
                 /* insert delimiting key from common father of dest and src to dest node into position 0 */
                 internal_insert_key(&dest_bi, 0, cf, d_key_position);
                 if (nr == pointer_amount - 1) {
                         RFALSE(src_bi.bi_bh != PATH_H_PBUFFER(tb->tb_path, h) /*tb->S[h] */ ||
                                dest_bi.bi_bh != tb->R[h],
                                "src (%p) must be == tb->S[h](%p) when it disappears",
                                src_bi.bi_bh, PATH_H_PBUFFER(tb->tb_path, h));
                         /* when S[h] disappers replace left delemiting key as well */
                         if (tb->CFL[h])
                                 replace_key(tb, cf, d_key_position, tb->CFL[h],
                                             tb->lkey[h]);
                 } else
                         replace_key(tb, cf, d_key_position, src_bi.bi_bh,
                                     nr - pointer_amount);
         }
 
         /* last parameter is del_parameter */
         internal_move_pointers_items(&dest_bi, &src_bi, LAST_TO_FIRST,
                                      pointer_amount, 0);
 }
 
 /* Insert delimiting key to R[h].
  * Copy n node pointers and n - 1 items from buffer S[h] to R[h].
  * Delete n - 1 items and node pointers from buffer S[h].
  */
 /* it always shift from S[h] to R[h] */
 static void internal_shift1_right(struct tree_balance *tb,
                                   int h, int pointer_amount)
 {
         struct buffer_info dest_bi, src_bi;
         struct buffer_head *cf;
         int d_key_position;
 
         internal_define_dest_src_infos(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
                                        &dest_bi, &src_bi, &d_key_position, &cf);
 
         if (pointer_amount > 0)        /* insert rkey from CFR[h] to right neighbor R[h] */
                 internal_insert_key(&dest_bi, 0, cf, d_key_position);
         /*            internal_insert_key (tb->R[h], 0, tb->CFR[h], tb->rkey[h]); */
 
         /* last parameter is del_parameter */
         internal_move_pointers_items(&dest_bi, &src_bi, LAST_TO_FIRST,
                                      pointer_amount, 1);
         /*    internal_move_pointers_items (tb->R[h], tb->S[h], LAST_TO_FIRST, pointer_amount, 1); */
 }
 
 /* Delete insert_num node pointers together with their left items
  * and balance current node.*/
 static void balance_internal_when_delete(struct tree_balance *tb,
                                          int h, int child_pos)
 {
         int insert_num;
         int n;
         struct buffer_head *tbSh = PATH_H_PBUFFER(tb->tb_path, h);
         struct buffer_info bi;
 
         insert_num = tb->insert_size[h] / ((int)(DC_SIZE + KEY_SIZE));
 
         /* delete child-node-pointer(s) together with their left item(s) */
         bi.tb = tb;
         bi.bi_bh = tbSh;
         bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
         bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
 
         internal_delete_childs(&bi, child_pos, -insert_num);
 
         RFALSE(tb->blknum[h] > 1,
                "tb->blknum[%d]=%d when insert_size < 0", h, tb->blknum[h]);
 
         n = B_NR_ITEMS(tbSh);
 
         if (tb->lnum[h] == 0 && tb->rnum[h] == 0) {
                 if (tb->blknum[h] == 0) {
                         /* node S[h] (root of the tree) is empty now */
                         struct buffer_head *new_root;
 
                         RFALSE(n
                                || B_FREE_SPACE(tbSh) !=
                                MAX_CHILD_SIZE(tbSh) - DC_SIZE,
                                "buffer must have only 0 keys (%d)", n);
                         RFALSE(bi.bi_parent, "root has parent (%p)",
                                bi.bi_parent);
 
                         /* choose a new root */
                         if (!tb->L[h - 1] || !B_NR_ITEMS(tb->L[h - 1]))
                                 new_root = tb->R[h - 1];
                         else
                                 new_root = tb->L[h - 1];
                         /* switch super block's tree root block number to the new value */
                         PUT_SB_ROOT_BLOCK(tb->tb_sb, new_root->b_blocknr);
                         //REISERFS_SB(tb->tb_sb)->s_rs->s_tree_height --;
                         PUT_SB_TREE_HEIGHT(tb->tb_sb,
                                            SB_TREE_HEIGHT(tb->tb_sb) - 1);
 
                         do_balance_mark_sb_dirty(tb,
                                                  REISERFS_SB(tb->tb_sb)->s_sbh,
                                                  1);
                         /*&&&&&&&&&&&&&&&&&&&&&& */
                         if (h > 1)
                                 /* use check_internal if new root is an internal node */
                                 check_internal(new_root);
                         /*&&&&&&&&&&&&&&&&&&&&&& */
 
                         /* do what is needed for buffer thrown from tree */
                         reiserfs_invalidate_buffer(tb, tbSh);
                         return;
                 }
                 return;
         }
 
         if (tb->L[h] && tb->lnum[h] == -B_NR_ITEMS(tb->L[h]) - 1) {        /* join S[h] with L[h] */
 
                 RFALSE(tb->rnum[h] != 0,
                        "invalid tb->rnum[%d]==%d when joining S[h] with L[h]",
                        h, tb->rnum[h]);
 
                 internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h, n + 1);
                 reiserfs_invalidate_buffer(tb, tbSh);
 
                 return;
         }
 
         if (tb->R[h] && tb->rnum[h] == -B_NR_ITEMS(tb->R[h]) - 1) {        /* join S[h] with R[h] */
                 RFALSE(tb->lnum[h] != 0,
                        "invalid tb->lnum[%d]==%d when joining S[h] with R[h]",
                        h, tb->lnum[h]);
 
                 internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h, n + 1);
 
                 reiserfs_invalidate_buffer(tb, tbSh);
                 return;
         }
 
         if (tb->lnum[h] < 0) {        /* borrow from left neighbor L[h] */
                 RFALSE(tb->rnum[h] != 0,
                        "wrong tb->rnum[%d]==%d when borrow from L[h]", h,
                        tb->rnum[h]);
                 /*internal_shift_right (tb, h, tb->L[h], tb->CFL[h], tb->lkey[h], tb->S[h], -tb->lnum[h]); */
                 internal_shift_right(INTERNAL_SHIFT_FROM_L_TO_S, tb, h,
                                      -tb->lnum[h]);
                 return;
         }
 
         if (tb->rnum[h] < 0) {        /* borrow from right neighbor R[h] */
                 RFALSE(tb->lnum[h] != 0,
                        "invalid tb->lnum[%d]==%d when borrow from R[h]",
                        h, tb->lnum[h]);
                 internal_shift_left(INTERNAL_SHIFT_FROM_R_TO_S, tb, h, -tb->rnum[h]);        /*tb->S[h], tb->CFR[h], tb->rkey[h], tb->R[h], -tb->rnum[h]); */
                 return;
         }
 
         if (tb->lnum[h] > 0) {        /* split S[h] into two parts and put them into neighbors */
                 RFALSE(tb->rnum[h] == 0 || tb->lnum[h] + tb->rnum[h] != n + 1,
                        "invalid tb->lnum[%d]==%d or tb->rnum[%d]==%d when S[h](item number == %d) is split between them",
                        h, tb->lnum[h], h, tb->rnum[h], n);
 
                 internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h, tb->lnum[h]);        /*tb->L[h], tb->CFL[h], tb->lkey[h], tb->S[h], tb->lnum[h]); */
                 internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
                                      tb->rnum[h]);
 
                 reiserfs_invalidate_buffer(tb, tbSh);
 
                 return;
         }
         reiserfs_panic(tb->tb_sb,
                        "balance_internal_when_delete: unexpected tb->lnum[%d]==%d or tb->rnum[%d]==%d",
                        h, tb->lnum[h], h, tb->rnum[h]);
 }
 
 /* Replace delimiting key of buffers L[h] and S[h] by the given key.*/
 static void replace_lkey(struct tree_balance *tb, int h, struct item_head *key)
 {
         RFALSE(tb->L[h] == NULL || tb->CFL[h] == NULL,
                "L[h](%p) and CFL[h](%p) must exist in replace_lkey",
                tb->L[h], tb->CFL[h]);
 
         if (B_NR_ITEMS(PATH_H_PBUFFER(tb->tb_path, h)) == 0)
                 return;
 
         memcpy(B_N_PDELIM_KEY(tb->CFL[h], tb->lkey[h]), key, KEY_SIZE);
 
         do_balance_mark_internal_dirty(tb, tb->CFL[h], 0);
 }
 
 /* Replace delimiting key of buffers S[h] and R[h] by the given key.*/
 static void replace_rkey(struct tree_balance *tb, int h, struct item_head *key)
 {
         RFALSE(tb->R[h] == NULL || tb->CFR[h] == NULL,
                "R[h](%p) and CFR[h](%p) must exist in replace_rkey",
                tb->R[h], tb->CFR[h]);
         RFALSE(B_NR_ITEMS(tb->R[h]) == 0,
                "R[h] can not be empty if it exists (item number=%d)",
                B_NR_ITEMS(tb->R[h]));
 
         memcpy(B_N_PDELIM_KEY(tb->CFR[h], tb->rkey[h]), key, KEY_SIZE);
 
         do_balance_mark_internal_dirty(tb, tb->CFR[h], 0);
 }
 
 int balance_internal(struct tree_balance *tb,        /* tree_balance structure               */
                      int h,        /* level of the tree                    */
                      int child_pos, struct item_head *insert_key,        /* key for insertion on higher level    */
                      struct buffer_head **insert_ptr        /* node for insertion on higher level */
     )
     /* if inserting/pasting
        {
        child_pos is the position of the node-pointer in S[h] that        *
        pointed to S[h-1] before balancing of the h-1 level;              *
        this means that new pointers and items must be inserted AFTER *
        child_pos
        }
        else 
        {
        it is the position of the leftmost pointer that must be deleted (together with
        its corresponding key to the left of the pointer)
        as a result of the previous level's balancing.
        }
      */
 {
         struct buffer_head *tbSh = PATH_H_PBUFFER(tb->tb_path, h);
         struct buffer_info bi;
         int order;                /* we return this: it is 0 if there is no S[h], else it is tb->S[h]->b_item_order */
         int insert_num, n, k;
         struct buffer_head *S_new;
         struct item_head new_insert_key;
         struct buffer_head *new_insert_ptr = NULL;
         struct item_head *new_insert_key_addr = insert_key;
 
         RFALSE(h < 1, "h (%d) can not be < 1 on internal level", h);
 
         PROC_INFO_INC(tb->tb_sb, balance_at[h]);
 
         order =
             (tbSh) ? PATH_H_POSITION(tb->tb_path,
                                      h + 1) /*tb->S[h]->b_item_order */ : 0;
 
         /* Using insert_size[h] calculate the number insert_num of items
            that must be inserted to or deleted from S[h]. */
         insert_num = tb->insert_size[h] / ((int)(KEY_SIZE + DC_SIZE));
 
         /* Check whether insert_num is proper * */
         RFALSE(insert_num < -2 || insert_num > 2,
                "incorrect number of items inserted to the internal node (%d)",
                insert_num);
         RFALSE(h > 1 && (insert_num > 1 || insert_num < -1),
                "incorrect number of items (%d) inserted to the internal node on a level (h=%d) higher than last internal level",
                insert_num, h);
 
         /* Make balance in case insert_num < 0 */
         if (insert_num < 0) {
                 balance_internal_when_delete(tb, h, child_pos);
                 return order;
         }
 
         k = 0;
         if (tb->lnum[h] > 0) {
                 /* shift lnum[h] items from S[h] to the left neighbor L[h].
                    check how many of new items fall into L[h] or CFL[h] after
                    shifting */
                 n = B_NR_ITEMS(tb->L[h]);        /* number of items in L[h] */
                 if (tb->lnum[h] <= child_pos) {
                         /* new items don't fall into L[h] or CFL[h] */
                         internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
                                             tb->lnum[h]);
                         /*internal_shift_left (tb->L[h],tb->CFL[h],tb->lkey[h],tbSh,tb->lnum[h]); */
                         child_pos -= tb->lnum[h];
                 } else if (tb->lnum[h] > child_pos + insert_num) {
                         /* all new items fall into L[h] */
                         internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
                                             tb->lnum[h] - insert_num);
                         /*                  internal_shift_left(tb->L[h],tb->CFL[h],tb->lkey[h],tbSh,
                            tb->lnum[h]-insert_num);
                          */
                         /* insert insert_num keys and node-pointers into L[h] */
                         bi.tb = tb;
                         bi.bi_bh = tb->L[h];
                         bi.bi_parent = tb->FL[h];
                         bi.bi_position = get_left_neighbor_position(tb, h);
                         internal_insert_childs(&bi,
                                                /*tb->L[h], tb->S[h-1]->b_next */
                                                n + child_pos + 1,
                                                insert_num, insert_key,
                                                insert_ptr);
 
                         insert_num = 0;
                 } else {
                         struct disk_child *dc;
 
                         /* some items fall into L[h] or CFL[h], but some don't fall */
                         internal_shift1_left(tb, h, child_pos + 1);
                         /* calculate number of new items that fall into L[h] */
                         k = tb->lnum[h] - child_pos - 1;
                         bi.tb = tb;
                         bi.bi_bh = tb->L[h];
                         bi.bi_parent = tb->FL[h];
                         bi.bi_position = get_left_neighbor_position(tb, h);
                         internal_insert_childs(&bi,
                                                /*tb->L[h], tb->S[h-1]->b_next, */
                                                n + child_pos + 1, k,
                                                insert_key, insert_ptr);
 
                         replace_lkey(tb, h, insert_key + k);
 
                         /* replace the first node-ptr in S[h] by node-ptr to insert_ptr[k] */
                         dc = B_N_CHILD(tbSh, 0);
                         put_dc_size(dc,
                                     MAX_CHILD_SIZE(insert_ptr[k]) -
                                     B_FREE_SPACE(insert_ptr[k]));
                         put_dc_block_number(dc, insert_ptr[k]->b_blocknr);
 
                         do_balance_mark_internal_dirty(tb, tbSh, 0);
 
                         k++;
                         insert_key += k;
                         insert_ptr += k;
                         insert_num -= k;
                         child_pos = 0;
                 }
         }
         /* tb->lnum[h] > 0 */
         if (tb->rnum[h] > 0) {
                 /*shift rnum[h] items from S[h] to the right neighbor R[h] */
                 /* check how many of new items fall into R or CFR after shifting */
                 n = B_NR_ITEMS(tbSh);        /* number of items in S[h] */
                 if (n - tb->rnum[h] >= child_pos)
                         /* new items fall into S[h] */
                         /*internal_shift_right(tb,h,tbSh,tb->CFR[h],tb->rkey[h],tb->R[h],tb->rnum[h]); */
                         internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
                                              tb->rnum[h]);
                 else if (n + insert_num - tb->rnum[h] < child_pos) {
                         /* all new items fall into R[h] */
                         /*internal_shift_right(tb,h,tbSh,tb->CFR[h],tb->rkey[h],tb->R[h],
                            tb->rnum[h] - insert_num); */
                         internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
                                              tb->rnum[h] - insert_num);
 
                         /* insert insert_num keys and node-pointers into R[h] */
                         bi.tb = tb;
                         bi.bi_bh = tb->R[h];
                         bi.bi_parent = tb->FR[h];
                         bi.bi_position = get_right_neighbor_position(tb, h);
                         internal_insert_childs(&bi,
                                                /*tb->R[h],tb->S[h-1]->b_next */
                                                child_pos - n - insert_num +
                                                tb->rnum[h] - 1,
                                                insert_num, insert_key,
                                                insert_ptr);
                         insert_num = 0;
                 } else {
                         struct disk_child *dc;
 
                         /* one of the items falls into CFR[h] */
                         internal_shift1_right(tb, h, n - child_pos + 1);
                         /* calculate number of new items that fall into R[h] */
                         k = tb->rnum[h] - n + child_pos - 1;
                         bi.tb = tb;
                         bi.bi_bh = tb->R[h];
                         bi.bi_parent = tb->FR[h];
                         bi.bi_position = get_right_neighbor_position(tb, h);
                         internal_insert_childs(&bi,
                                                /*tb->R[h], tb->R[h]->b_child, */
                                                0, k, insert_key + 1,
                                                insert_ptr + 1);
 
                         replace_rkey(tb, h, insert_key + insert_num - k - 1);
 
                         /* replace the first node-ptr in R[h] by node-ptr insert_ptr[insert_num-k-1] */
                         dc = B_N_CHILD(tb->R[h], 0);
                         put_dc_size(dc,
                                     MAX_CHILD_SIZE(insert_ptr
                                                    [insert_num - k - 1]) -
                                     B_FREE_SPACE(insert_ptr
                                                  [insert_num - k - 1]));
                         put_dc_block_number(dc,
                                             insert_ptr[insert_num - k -
                                                        1]->b_blocknr);
 
                         do_balance_mark_internal_dirty(tb, tb->R[h], 0);
 
                         insert_num -= (k + 1);
                 }
         }
 
     /** Fill new node that appears instead of S[h] **/
         RFALSE(tb->blknum[h] > 2, "blknum can not be > 2 for internal level");
         RFALSE(tb->blknum[h] < 0, "blknum can not be < 0");
 
         if (!tb->blknum[h]) {        /* node S[h] is empty now */
                 RFALSE(!tbSh, "S[h] is equal NULL");
 
                 /* do what is needed for buffer thrown from tree */
                 reiserfs_invalidate_buffer(tb, tbSh);
                 return order;
         }
 
         if (!tbSh) {
                 /* create new root */
                 struct disk_child *dc;
                 struct buffer_head *tbSh_1 = PATH_H_PBUFFER(tb->tb_path, h - 1);
                 struct block_head *blkh;
 
                 if (tb->blknum[h] != 1)
                         reiserfs_panic(NULL,
                                        "balance_internal: One new node required for creating the new root");
                 /* S[h] = empty buffer from the list FEB. */
                 tbSh = get_FEB(tb);
                 blkh = B_BLK_HEAD(tbSh);
                 set_blkh_level(blkh, h + 1);
 
                 /* Put the unique node-pointer to S[h] that points to S[h-1]. */
 
                 dc = B_N_CHILD(tbSh, 0);
                 put_dc_block_number(dc, tbSh_1->b_blocknr);
                 put_dc_size(dc,
                             (MAX_CHILD_SIZE(tbSh_1) - B_FREE_SPACE(tbSh_1)));
 
                 tb->insert_size[h] -= DC_SIZE;
                 set_blkh_free_space(blkh, blkh_free_space(blkh) - DC_SIZE);
 
                 do_balance_mark_internal_dirty(tb, tbSh, 0);
 
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
                 check_internal(tbSh);
                 /*&&&&&&&&&&&&&&&&&&&&&&&& */
 
                 /* put new root into path structure */
                 PATH_OFFSET_PBUFFER(tb->tb_path, ILLEGAL_PATH_ELEMENT_OFFSET) =
                     tbSh;
 
                 /* Change root in structure super block. */
                 PUT_SB_ROOT_BLOCK(tb->tb_sb, tbSh->b_blocknr);
                 PUT_SB_TREE_HEIGHT(tb->tb_sb, SB_TREE_HEIGHT(tb->tb_sb) + 1);
                 do_balance_mark_sb_dirty(tb, REISERFS_SB(tb->tb_sb)->s_sbh, 1);
         }
 
         if (tb->blknum[h] == 2) {
                 int snum;
                 struct buffer_info dest_bi, src_bi;
 
                 /* S_new = free buffer from list FEB */
                 S_new = get_FEB(tb);
 
                 set_blkh_level(B_BLK_HEAD(S_new), h + 1);
 
                 dest_bi.tb = tb;
                 dest_bi.bi_bh = S_new;
                 dest_bi.bi_parent = NULL;
                 dest_bi.bi_position = 0;
                 src_bi.tb = tb;
                 src_bi.bi_bh = tbSh;
                 src_bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
                 src_bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
 
                 n = B_NR_ITEMS(tbSh);        /* number of items in S[h] */
                 snum = (insert_num + n + 1) / 2;
                 if (n - snum >= child_pos) {
                         /* new items don't fall into S_new */
                         /*  store the delimiting key for the next level */
                         /* new_insert_key = (n - snum)'th key in S[h] */
                        memcpy(&new_insert_key, B_N_PDELIM_KEY(tbSh, n - snum),
                               KEY_SIZE);
                        /* last parameter is del_par */
                        internal_move_pointers_items(&dest_bi, &src_bi,
                                                     LAST_TO_FIRST, snum, 0);
                        /*            internal_move_pointers_items(S_new, tbSh, LAST_TO_FIRST, snum, 0); */
                } else if (n + insert_num - snum < child_pos) {
                        /* all new items fall into S_new */
                        /*  store the delimiting key for the next level */
                        /* new_insert_key = (n + insert_item - snum)'th key in S[h] */
                        memcpy(&new_insert_key,
                               B_N_PDELIM_KEY(tbSh, n + insert_num - snum),
                               KEY_SIZE);
                        /* last parameter is del_par */
                        internal_move_pointers_items(&dest_bi, &src_bi,
                                                     LAST_TO_FIRST,
                                                     snum - insert_num, 0);
                        /*                  internal_move_pointers_items(S_new,tbSh,1,snum - insert_num,0); */

                        /* insert insert_num keys and node-pointers into S_new */
                        internal_insert_childs(&dest_bi,
                                               /*S_new,tb->S[h-1]->b_next, */
                                               child_pos - n - insert_num +
                                               snum - 1,
                                               insert_num, insert_key,
                                               insert_ptr);

                        insert_num = 0;
                } else {
                        struct disk_child *dc;

                        /* some items fall into S_new, but some don't fall */
                        /* last parameter is del_par */
                        internal_move_pointers_items(&dest_bi, &src_bi,
                                                     LAST_TO_FIRST,
                                                     n - child_pos + 1, 1);
                        /*                  internal_move_pointers_items(S_new,tbSh,1,n - child_pos + 1,1); */
                        /* calculate number of new items that fall into S_new */
                        k = snum - n + child_pos - 1;

                        internal_insert_childs(&dest_bi, /*S_new, */ 0, k,
                                               insert_key + 1, insert_ptr + 1);

                        /* new_insert_key = insert_key[insert_num - k - 1] */
                        memcpy(&new_insert_key, insert_key + insert_num - k - 1,
                               KEY_SIZE);
                        /* replace first node-ptr in S_new by node-ptr to insert_ptr[insert_num-k-1] */

                        dc = B_N_CHILD(S_new, 0);
                        put_dc_size(dc,
                                    (MAX_CHILD_SIZE
                                     (insert_ptr[insert_num - k - 1]) -
                                     B_FREE_SPACE(insert_ptr
                                                  [insert_num - k - 1])));
                        put_dc_block_number(dc,
                                            insert_ptr[insert_num - k -
                                                       1]->b_blocknr);

                        do_balance_mark_internal_dirty(tb, S_new, 0);

                        insert_num -= (k + 1);
                }
                /* new_insert_ptr = node_pointer to S_new */
                new_insert_ptr = S_new;

                RFALSE(!buffer_journaled(S_new) || buffer_journal_dirty(S_new)
                       || buffer_dirty(S_new), "cm-00001: bad S_new (%b)",
                       S_new);

                // S_new is released in unfix_nodes
        }

        n = B_NR_ITEMS(tbSh);        /*number of items in S[h] */

        if (0 <= child_pos && child_pos <= n && insert_num > 0) {
                bi.tb = tb;
                bi.bi_bh = tbSh;
                bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
                bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
                internal_insert_childs(&bi,        /*tbSh, */
                                       /*          ( tb->S[h-1]->b_parent == tb->S[h] ) ? tb->S[h-1]->b_next :  tb->S[h]->b_child->b_next, */
                                       child_pos, insert_num, insert_key,
                                       insert_ptr);
        }

        memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE);
        insert_ptr[0] = new_insert_ptr;

        return order;
}