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lbalance.c

/*
 * 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>

/* these are used in do_balance.c */

/* leaf_move_items
   leaf_shift_left
   leaf_shift_right
   leaf_delete_items
   leaf_insert_into_buf
   leaf_paste_in_buffer
   leaf_cut_from_buffer
   leaf_paste_entries
   */

/* copy copy_count entries from source directory item to dest buffer (creating new item if needed) */
static void leaf_copy_dir_entries(struct buffer_info *dest_bi,
                          struct buffer_head *source, int last_first,
                          int item_num, int from, int copy_count)
{
      struct buffer_head *dest = dest_bi->bi_bh;
      int item_num_in_dest;   /* either the number of target item,
                           or if we must create a new item,
                           the number of the item we will
                           create it next to */
      struct item_head *ih;
      struct reiserfs_de_head *deh;
      int copy_records_len;   /* length of all records in item to be copied */
      char *records;

      ih = B_N_PITEM_HEAD(source, item_num);

      RFALSE(!is_direntry_le_ih(ih), "vs-10000: item must be directory item");

      /* length of all record to be copied and first byte of the last of them */
      deh = B_I_DEH(source, ih);
      if (copy_count) {
            copy_records_len = (from ? deh_location(&(deh[from - 1])) :
                            ih_item_len(ih)) -
                deh_location(&(deh[from + copy_count - 1]));
            records =
                source->b_data + ih_location(ih) +
                deh_location(&(deh[from + copy_count - 1]));
      } else {
            copy_records_len = 0;
            records = NULL;
      }

      /* when copy last to first, dest buffer can contain 0 items */
      item_num_in_dest =
          (last_first ==
           LAST_TO_FIRST) ? ((B_NR_ITEMS(dest)) ? 0 : -1) : (B_NR_ITEMS(dest)
                                                 - 1);

      /* if there are no items in dest or the first/last item in dest is not item of the same directory */
      if ((item_num_in_dest == -1) ||
          (last_first == FIRST_TO_LAST && le_ih_k_offset(ih) == DOT_OFFSET) ||
          (last_first == LAST_TO_FIRST
           && comp_short_le_keys /*COMP_SHORT_KEYS */ (&ih->ih_key,
                                           B_N_PKEY(dest,
                                                  item_num_in_dest))))
      {
            /* create new item in dest */
            struct item_head new_ih;

            /* form item header */
            memcpy(&new_ih.ih_key, &ih->ih_key, KEY_SIZE);
            put_ih_version(&new_ih, KEY_FORMAT_3_5);
            /* calculate item len */
            put_ih_item_len(&new_ih,
                        DEH_SIZE * copy_count + copy_records_len);
            put_ih_entry_count(&new_ih, 0);

            if (last_first == LAST_TO_FIRST) {
                  /* form key by the following way */
                  if (from < I_ENTRY_COUNT(ih)) {
                        set_le_ih_k_offset(&new_ih,
                                       deh_offset(&(deh[from])));
                        /*memcpy (&new_ih.ih_key.k_offset, &deh[from].deh_offset, SHORT_KEY_SIZE); */
                  } else {
                        /* no entries will be copied to this item in this function */
                        set_le_ih_k_offset(&new_ih, U32_MAX);
                        /* this item is not yet valid, but we want I_IS_DIRECTORY_ITEM to return 1 for it, so we -1 */
                  }
                  set_le_key_k_type(KEY_FORMAT_3_5, &(new_ih.ih_key),
                                TYPE_DIRENTRY);
            }

            /* insert item into dest buffer */
            leaf_insert_into_buf(dest_bi,
                             (last_first ==
                              LAST_TO_FIRST) ? 0 : B_NR_ITEMS(dest),
                             &new_ih, NULL, 0);
      } else {
            /* prepare space for entries */
            leaf_paste_in_buffer(dest_bi,
                             (last_first ==
                              FIRST_TO_LAST) ? (B_NR_ITEMS(dest) -
                                          1) : 0, MAX_US_INT,
                             DEH_SIZE * copy_count + copy_records_len,
                             records, 0);
      }

      item_num_in_dest =
          (last_first == FIRST_TO_LAST) ? (B_NR_ITEMS(dest) - 1) : 0;

      leaf_paste_entries(dest_bi->bi_bh, item_num_in_dest,
                     (last_first ==
                      FIRST_TO_LAST) ? I_ENTRY_COUNT(B_N_PITEM_HEAD(dest,
                                                        item_num_in_dest))
                     : 0, copy_count, deh + from, records,
                     DEH_SIZE * copy_count + copy_records_len);
}

/* Copy the first (if last_first == FIRST_TO_LAST) or last (last_first == LAST_TO_FIRST) item or 
   part of it or nothing (see the return 0 below) from SOURCE to the end 
   (if last_first) or beginning (!last_first) of the DEST */
/* returns 1 if anything was copied, else 0 */
static int leaf_copy_boundary_item(struct buffer_info *dest_bi,
                           struct buffer_head *src, int last_first,
                           int bytes_or_entries)
{
      struct buffer_head *dest = dest_bi->bi_bh;
      int dest_nr_item, src_nr_item;      /* number of items in the source and destination buffers */
      struct item_head *ih;
      struct item_head *dih;

      dest_nr_item = B_NR_ITEMS(dest);

      if (last_first == FIRST_TO_LAST) {
            /* if ( DEST is empty or first item of SOURCE and last item of DEST are the items of different objects
               or of different types ) then there is no need to treat this item differently from the other items
               that we copy, so we return */
            ih = B_N_PITEM_HEAD(src, 0);
            dih = B_N_PITEM_HEAD(dest, dest_nr_item - 1);
            if (!dest_nr_item
                || (!op_is_left_mergeable(&(ih->ih_key), src->b_size)))
                  /* there is nothing to merge */
                  return 0;

            RFALSE(!ih_item_len(ih),
                   "vs-10010: item can not have empty length");

            if (is_direntry_le_ih(ih)) {
                  if (bytes_or_entries == -1)
                        /* copy all entries to dest */
                        bytes_or_entries = ih_entry_count(ih);
                  leaf_copy_dir_entries(dest_bi, src, FIRST_TO_LAST, 0, 0,
                                    bytes_or_entries);
                  return 1;
            }

            /* copy part of the body of the first item of SOURCE to the end of the body of the last item of the DEST
               part defined by 'bytes_or_entries'; if bytes_or_entries == -1 copy whole body; don't create new item header
             */
            if (bytes_or_entries == -1)
                  bytes_or_entries = ih_item_len(ih);

#ifdef CONFIG_REISERFS_CHECK
            else {
                  if (bytes_or_entries == ih_item_len(ih)
                      && is_indirect_le_ih(ih))
                        if (get_ih_free_space(ih))
                              reiserfs_panic(NULL,
                                           "vs-10020: leaf_copy_boundary_item: "
                                           "last unformatted node must be filled entirely (%h)",
                                           ih);
            }
#endif

            /* merge first item (or its part) of src buffer with the last
               item of dest buffer. Both are of the same file */
            leaf_paste_in_buffer(dest_bi,
                             dest_nr_item - 1, ih_item_len(dih),
                             bytes_or_entries, B_I_PITEM(src, ih), 0);

            if (is_indirect_le_ih(dih)) {
                  RFALSE(get_ih_free_space(dih),
                         "vs-10030: merge to left: last unformatted node of non-last indirect item %h must have zerto free space",
                         ih);
                  if (bytes_or_entries == ih_item_len(ih))
                        set_ih_free_space(dih, get_ih_free_space(ih));
            }

            return 1;
      }

      /* copy boundary item to right (last_first == LAST_TO_FIRST) */

      /* ( DEST is empty or last item of SOURCE and first item of DEST
         are the items of different object or of different types )
       */
      src_nr_item = B_NR_ITEMS(src);
      ih = B_N_PITEM_HEAD(src, src_nr_item - 1);
      dih = B_N_PITEM_HEAD(dest, 0);

      if (!dest_nr_item || !op_is_left_mergeable(&(dih->ih_key), src->b_size))
            return 0;

      if (is_direntry_le_ih(ih)) {
            if (bytes_or_entries == -1)
                  /* bytes_or_entries = entries number in last item body of SOURCE */
                  bytes_or_entries = ih_entry_count(ih);

            leaf_copy_dir_entries(dest_bi, src, LAST_TO_FIRST,
                              src_nr_item - 1,
                              ih_entry_count(ih) - bytes_or_entries,
                              bytes_or_entries);
            return 1;
      }

      /* copy part of the body of the last item of SOURCE to the begin of the body of the first item of the DEST;
         part defined by 'bytes_or_entries'; if byte_or_entriess == -1 copy whole body; change first item key of the DEST;
         don't create new item header
       */

      RFALSE(is_indirect_le_ih(ih) && get_ih_free_space(ih),
             "vs-10040: merge to right: last unformatted node of non-last indirect item must be filled entirely (%h)",
             ih);

      if (bytes_or_entries == -1) {
            /* bytes_or_entries = length of last item body of SOURCE */
            bytes_or_entries = ih_item_len(ih);

            RFALSE(le_ih_k_offset(dih) !=
                   le_ih_k_offset(ih) + op_bytes_number(ih, src->b_size),
                   "vs-10050: items %h and %h do not match", ih, dih);

            /* change first item key of the DEST */
            set_le_ih_k_offset(dih, le_ih_k_offset(ih));

            /* item becomes non-mergeable */
            /* or mergeable if left item was */
            set_le_ih_k_type(dih, le_ih_k_type(ih));
      } else {
            /* merge to right only part of item */
            RFALSE(ih_item_len(ih) <= bytes_or_entries,
                   "vs-10060: no so much bytes %lu (needed %lu)",
                   (unsigned long)ih_item_len(ih),
                   (unsigned long)bytes_or_entries);

            /* change first item key of the DEST */
            if (is_direct_le_ih(dih)) {
                  RFALSE(le_ih_k_offset(dih) <=
                         (unsigned long)bytes_or_entries,
                         "vs-10070: dih %h, bytes_or_entries(%d)", dih,
                         bytes_or_entries);
                  set_le_ih_k_offset(dih,
                                 le_ih_k_offset(dih) -
                                 bytes_or_entries);
            } else {
                  RFALSE(le_ih_k_offset(dih) <=
                         (bytes_or_entries / UNFM_P_SIZE) * dest->b_size,
                         "vs-10080: dih %h, bytes_or_entries(%d)",
                         dih,
                         (bytes_or_entries / UNFM_P_SIZE) * dest->b_size);
                  set_le_ih_k_offset(dih,
                                 le_ih_k_offset(dih) -
                                 ((bytes_or_entries / UNFM_P_SIZE) *
                                  dest->b_size));
            }
      }

      leaf_paste_in_buffer(dest_bi, 0, 0, bytes_or_entries,
                       B_I_PITEM(src,
                               ih) + ih_item_len(ih) - bytes_or_entries,
                       0);
      return 1;
}

/* copy cpy_mun items from buffer src to buffer dest
 * last_first == FIRST_TO_LAST means, that we copy cpy_num  items beginning from first-th item in src to tail of dest
 * last_first == LAST_TO_FIRST means, that we copy cpy_num  items beginning from first-th item in src to head of dest
 */
static void leaf_copy_items_entirely(struct buffer_info *dest_bi,
                             struct buffer_head *src, int last_first,
                             int first, int cpy_num)
{
      struct buffer_head *dest;
      int nr, free_space;
      int dest_before;
      int last_loc, last_inserted_loc, location;
      int i, j;
      struct block_head *blkh;
      struct item_head *ih;

      RFALSE(last_first != LAST_TO_FIRST && last_first != FIRST_TO_LAST,
             "vs-10090: bad last_first parameter %d", last_first);
      RFALSE(B_NR_ITEMS(src) - first < cpy_num,
             "vs-10100: too few items in source %d, required %d from %d",
             B_NR_ITEMS(src), cpy_num, first);
      RFALSE(cpy_num < 0, "vs-10110: can not copy negative amount of items");
      RFALSE(!dest_bi, "vs-10120: can not copy negative amount of items");

      dest = dest_bi->bi_bh;

      RFALSE(!dest, "vs-10130: can not copy negative amount of items");

      if (cpy_num == 0)
            return;

      blkh = B_BLK_HEAD(dest);
      nr = blkh_nr_item(blkh);
      free_space = blkh_free_space(blkh);

      /* we will insert items before 0-th or nr-th item in dest buffer. It depends of last_first parameter */
      dest_before = (last_first == LAST_TO_FIRST) ? 0 : nr;

      /* location of head of first new item */
      ih = B_N_PITEM_HEAD(dest, dest_before);

      RFALSE(blkh_free_space(blkh) < cpy_num * IH_SIZE,
             "vs-10140: not enough free space for headers %d (needed %d)",
             B_FREE_SPACE(dest), cpy_num * IH_SIZE);

      /* prepare space for headers */
      memmove(ih + cpy_num, ih, (nr - dest_before) * IH_SIZE);

      /* copy item headers */
      memcpy(ih, B_N_PITEM_HEAD(src, first), cpy_num * IH_SIZE);

      free_space -= (IH_SIZE * cpy_num);
      set_blkh_free_space(blkh, free_space);

      /* location of unmovable item */
      j = location = (dest_before == 0) ? dest->b_size : ih_location(ih - 1);
      for (i = dest_before; i < nr + cpy_num; i++) {
            location -= ih_item_len(ih + i - dest_before);
            put_ih_location(ih + i - dest_before, location);
      }

      /* prepare space for items */
      last_loc = ih_location(&(ih[nr + cpy_num - 1 - dest_before]));
      last_inserted_loc = ih_location(&(ih[cpy_num - 1]));

      /* check free space */
      RFALSE(free_space < j - last_inserted_loc,
             "vs-10150: not enough free space for items %d (needed %d)",
             free_space, j - last_inserted_loc);

      memmove(dest->b_data + last_loc,
            dest->b_data + last_loc + j - last_inserted_loc,
            last_inserted_loc - last_loc);

      /* copy items */
      memcpy(dest->b_data + last_inserted_loc,
             B_N_PITEM(src, (first + cpy_num - 1)), j - last_inserted_loc);

      /* sizes, item number */
      set_blkh_nr_item(blkh, nr + cpy_num);
      set_blkh_free_space(blkh, free_space - (j - last_inserted_loc));

      do_balance_mark_leaf_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);
            RFALSE(dc_block_number(t_dc) != dest->b_blocknr,
                   "vs-10160: block number in bh does not match to field in disk_child structure %lu and %lu",
                   (long unsigned)dest->b_blocknr,
                   (long unsigned)dc_block_number(t_dc));
            put_dc_size(t_dc,
                      dc_size(t_dc) + (j - last_inserted_loc +
                                   IH_SIZE * cpy_num));

            do_balance_mark_internal_dirty(dest_bi->tb, dest_bi->bi_parent,
                                     0);
      }
}

/* This function splits the (liquid) item into two items (useful when
   shifting part of an item into another node.) */
static void leaf_item_bottle(struct buffer_info *dest_bi,
                       struct buffer_head *src, int last_first,
                       int item_num, int cpy_bytes)
{
      struct buffer_head *dest = dest_bi->bi_bh;
      struct item_head *ih;

      RFALSE(cpy_bytes == -1,
             "vs-10170: bytes == - 1 means: do not split item");

      if (last_first == FIRST_TO_LAST) {
            /* if ( if item in position item_num in buffer SOURCE is directory item ) */
            if (is_direntry_le_ih(ih = B_N_PITEM_HEAD(src, item_num)))
                  leaf_copy_dir_entries(dest_bi, src, FIRST_TO_LAST,
                                    item_num, 0, cpy_bytes);
            else {
                  struct item_head n_ih;

                  /* copy part of the body of the item number 'item_num' of SOURCE to the end of the DEST 
                     part defined by 'cpy_bytes'; create new item header; change old item_header (????);
                     n_ih = new item_header;
                   */
                  memcpy(&n_ih, ih, IH_SIZE);
                  put_ih_item_len(&n_ih, cpy_bytes);
                  if (is_indirect_le_ih(ih)) {
                        RFALSE(cpy_bytes == ih_item_len(ih)
                               && get_ih_free_space(ih),
                               "vs-10180: when whole indirect item is bottle to left neighbor, it must have free_space==0 (not %lu)",
                               (long unsigned)get_ih_free_space(ih));
                        set_ih_free_space(&n_ih, 0);
                  }

                  RFALSE(op_is_left_mergeable(&(ih->ih_key), src->b_size),
                         "vs-10190: bad mergeability of item %h", ih);
                  n_ih.ih_version = ih->ih_version;   /* JDM Endian safe, both le */
                  leaf_insert_into_buf(dest_bi, B_NR_ITEMS(dest), &n_ih,
                                   B_N_PITEM(src, item_num), 0);
            }
      } else {
            /*  if ( if item in position item_num in buffer SOURCE is directory item ) */
            if (is_direntry_le_ih(ih = B_N_PITEM_HEAD(src, item_num)))
                  leaf_copy_dir_entries(dest_bi, src, LAST_TO_FIRST,
                                    item_num,
                                    I_ENTRY_COUNT(ih) - cpy_bytes,
                                    cpy_bytes);
            else {
                  struct item_head n_ih;

                  /* copy part of the body of the item number 'item_num' of SOURCE to the begin of the DEST 
                     part defined by 'cpy_bytes'; create new item header;
                     n_ih = new item_header;
                   */
                  memcpy(&n_ih, ih, SHORT_KEY_SIZE);

                  n_ih.ih_version = ih->ih_version;   /* JDM Endian safe, both le */

                  if (is_direct_le_ih(ih)) {
                        set_le_ih_k_offset(&n_ih,
                                       le_ih_k_offset(ih) +
                                       ih_item_len(ih) - cpy_bytes);
                        set_le_ih_k_type(&n_ih, TYPE_DIRECT);
                        set_ih_free_space(&n_ih, MAX_US_INT);
                  } else {
                        /* indirect item */
                        RFALSE(!cpy_bytes && get_ih_free_space(ih),
                               "vs-10200: ih->ih_free_space must be 0 when indirect item will be appended");
                        set_le_ih_k_offset(&n_ih,
                                       le_ih_k_offset(ih) +
                                       (ih_item_len(ih) -
                                        cpy_bytes) / UNFM_P_SIZE *
                                       dest->b_size);
                        set_le_ih_k_type(&n_ih, TYPE_INDIRECT);
                        set_ih_free_space(&n_ih, get_ih_free_space(ih));
                  }

                  /* set item length */
                  put_ih_item_len(&n_ih, cpy_bytes);

                  n_ih.ih_version = ih->ih_version;   /* JDM Endian safe, both le */

                  leaf_insert_into_buf(dest_bi, 0, &n_ih,
                                   B_N_PITEM(src,
                                           item_num) +
                                   ih_item_len(ih) - cpy_bytes, 0);
            }
      }
}

/* If cpy_bytes equals minus one than copy cpy_num whole items from SOURCE to DEST.
   If cpy_bytes not equal to minus one than copy cpy_num-1 whole items from SOURCE to DEST.
   From last item copy cpy_num bytes for regular item and cpy_num directory entries for
   directory item. */
static int leaf_copy_items(struct buffer_info *dest_bi, struct buffer_head *src,
                     int last_first, int cpy_num, int cpy_bytes)
{
      struct buffer_head *dest;
      int pos, i, src_nr_item, bytes;

      dest = dest_bi->bi_bh;
      RFALSE(!dest || !src, "vs-10210: !dest || !src");
      RFALSE(last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST,
             "vs-10220:last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST");
      RFALSE(B_NR_ITEMS(src) < cpy_num,
             "vs-10230: No enough items: %d, req. %d", B_NR_ITEMS(src),
             cpy_num);
      RFALSE(cpy_num < 0, "vs-10240: cpy_num < 0 (%d)", cpy_num);

      if (cpy_num == 0)
            return 0;

      if (last_first == FIRST_TO_LAST) {
            /* copy items to left */
            pos = 0;
            if (cpy_num == 1)
                  bytes = cpy_bytes;
            else
                  bytes = -1;

            /* copy the first item or it part or nothing to the end of the DEST (i = leaf_copy_boundary_item(DEST,SOURCE,0,bytes)) */
            i = leaf_copy_boundary_item(dest_bi, src, FIRST_TO_LAST, bytes);
            cpy_num -= i;
            if (cpy_num == 0)
                  return i;
            pos += i;
            if (cpy_bytes == -1)
                  /* copy first cpy_num items starting from position 'pos' of SOURCE to end of DEST */
                  leaf_copy_items_entirely(dest_bi, src, FIRST_TO_LAST,
                                     pos, cpy_num);
            else {
                  /* copy first cpy_num-1 items starting from position 'pos-1' of the SOURCE to the end of the DEST */
                  leaf_copy_items_entirely(dest_bi, src, FIRST_TO_LAST,
                                     pos, cpy_num - 1);

                  /* copy part of the item which number is cpy_num+pos-1 to the end of the DEST */
                  leaf_item_bottle(dest_bi, src, FIRST_TO_LAST,
                               cpy_num + pos - 1, cpy_bytes);
            }
      } else {
            /* copy items to right */
            src_nr_item = B_NR_ITEMS(src);
            if (cpy_num == 1)
                  bytes = cpy_bytes;
            else
                  bytes = -1;

            /* copy the last item or it part or nothing to the begin of the DEST (i = leaf_copy_boundary_item(DEST,SOURCE,1,bytes)); */
            i = leaf_copy_boundary_item(dest_bi, src, LAST_TO_FIRST, bytes);

            cpy_num -= i;
            if (cpy_num == 0)
                  return i;

            pos = src_nr_item - cpy_num - i;
            if (cpy_bytes == -1) {
                  /* starting from position 'pos' copy last cpy_num items of SOURCE to begin of DEST */
                  leaf_copy_items_entirely(dest_bi, src, LAST_TO_FIRST,
                                     pos, cpy_num);
            } else {
                  /* copy last cpy_num-1 items starting from position 'pos+1' of the SOURCE to the begin of the DEST; */
                  leaf_copy_items_entirely(dest_bi, src, LAST_TO_FIRST,
                                     pos + 1, cpy_num - 1);

                  /* copy part of the item which number is pos to the begin of the DEST */
                  leaf_item_bottle(dest_bi, src, LAST_TO_FIRST, pos,
                               cpy_bytes);
            }
      }
      return i;
}

/* there are types of coping: from S[0] to L[0], from S[0] to R[0],
   from R[0] to L[0]. for each of these we have to define parent and
   positions of destination and source buffers */
static void leaf_define_dest_src_infos(int shift_mode, struct tree_balance *tb,
                               struct buffer_info *dest_bi,
                               struct buffer_info *src_bi,
                               int *first_last,
                               struct buffer_head *Snew)
{
      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 LEAF_FROM_S_TO_L:  /* it is used in leaf_shift_left */
            src_bi->tb = tb;
            src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
            src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
            src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);  /* src->b_item_order */
            dest_bi->tb = tb;
            dest_bi->bi_bh = tb->L[0];
            dest_bi->bi_parent = tb->FL[0];
            dest_bi->bi_position = get_left_neighbor_position(tb, 0);
            *first_last = FIRST_TO_LAST;
            break;

      case LEAF_FROM_S_TO_R:  /* it is used in leaf_shift_right */
            src_bi->tb = tb;
            src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
            src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
            src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);
            dest_bi->tb = tb;
            dest_bi->bi_bh = tb->R[0];
            dest_bi->bi_parent = tb->FR[0];
            dest_bi->bi_position = get_right_neighbor_position(tb, 0);
            *first_last = LAST_TO_FIRST;
            break;

      case LEAF_FROM_R_TO_L:  /* it is used in balance_leaf_when_delete */
            src_bi->tb = tb;
            src_bi->bi_bh = tb->R[0];
            src_bi->bi_parent = tb->FR[0];
            src_bi->bi_position = get_right_neighbor_position(tb, 0);
            dest_bi->tb = tb;
            dest_bi->bi_bh = tb->L[0];
            dest_bi->bi_parent = tb->FL[0];
            dest_bi->bi_position = get_left_neighbor_position(tb, 0);
            *first_last = FIRST_TO_LAST;
            break;

      case LEAF_FROM_L_TO_R:  /* it is used in balance_leaf_when_delete */
            src_bi->tb = tb;
            src_bi->bi_bh = tb->L[0];
            src_bi->bi_parent = tb->FL[0];
            src_bi->bi_position = get_left_neighbor_position(tb, 0);
            dest_bi->tb = tb;
            dest_bi->bi_bh = tb->R[0];
            dest_bi->bi_parent = tb->FR[0];
            dest_bi->bi_position = get_right_neighbor_position(tb, 0);
            *first_last = LAST_TO_FIRST;
            break;

      case LEAF_FROM_S_TO_SNEW:
            src_bi->tb = tb;
            src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
            src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
            src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);
            dest_bi->tb = tb;
            dest_bi->bi_bh = Snew;
            dest_bi->bi_parent = NULL;
            dest_bi->bi_position = 0;
            *first_last = LAST_TO_FIRST;
            break;

      default:
            reiserfs_panic(NULL,
                         "vs-10250: leaf_define_dest_src_infos: shift type is unknown (%d)",
                         shift_mode);
      }
      RFALSE(src_bi->bi_bh == 0 || dest_bi->bi_bh == 0,
             "vs-10260: mode==%d, source (%p) or dest (%p) buffer is initialized incorrectly",
             shift_mode, src_bi->bi_bh, dest_bi->bi_bh);
}

/* copy mov_num items and mov_bytes of the (mov_num-1)th item to
   neighbor. Delete them from source */
int leaf_move_items(int shift_mode, struct tree_balance *tb, int mov_num,
                int mov_bytes, struct buffer_head *Snew)
{
      int ret_value;
      struct buffer_info dest_bi, src_bi;
      int first_last;

      leaf_define_dest_src_infos(shift_mode, tb, &dest_bi, &src_bi,
                           &first_last, Snew);

      ret_value =
          leaf_copy_items(&dest_bi, src_bi.bi_bh, first_last, mov_num,
                      mov_bytes);

      leaf_delete_items(&src_bi, first_last,
                    (first_last ==
                     FIRST_TO_LAST) ? 0 : (B_NR_ITEMS(src_bi.bi_bh) -
                                     mov_num), mov_num, mov_bytes);

      return ret_value;
}

/* Shift shift_num items (and shift_bytes of last shifted item if shift_bytes != -1)
   from S[0] to L[0] and replace the delimiting key */
int leaf_shift_left(struct tree_balance *tb, int shift_num, int shift_bytes)
{
      struct buffer_head *S0 = PATH_PLAST_BUFFER(tb->tb_path);
      int i;

      /* move shift_num (and shift_bytes bytes) items from S[0] to left neighbor L[0] */
      i = leaf_move_items(LEAF_FROM_S_TO_L, tb, shift_num, shift_bytes, NULL);

      if (shift_num) {
            if (B_NR_ITEMS(S0) == 0) {    /* number of items in S[0] == 0 */

                  RFALSE(shift_bytes != -1,
                         "vs-10270: S0 is empty now, but shift_bytes != -1 (%d)",
                         shift_bytes);
#ifdef CONFIG_REISERFS_CHECK
                  if (tb->tb_mode == M_PASTE || tb->tb_mode == M_INSERT) {
                        print_cur_tb("vs-10275");
                        reiserfs_panic(tb->tb_sb,
                                     "vs-10275: leaf_shift_left: balance condition corrupted (%c)",
                                     tb->tb_mode);
                  }
#endif

                  if (PATH_H_POSITION(tb->tb_path, 1) == 0)
                        replace_key(tb, tb->CFL[0], tb->lkey[0],
                                  PATH_H_PPARENT(tb->tb_path, 0), 0);

            } else {
                  /* replace lkey in CFL[0] by 0-th key from S[0]; */
                  replace_key(tb, tb->CFL[0], tb->lkey[0], S0, 0);

                  RFALSE((shift_bytes != -1 &&
                        !(is_direntry_le_ih(B_N_PITEM_HEAD(S0, 0))
                          && !I_ENTRY_COUNT(B_N_PITEM_HEAD(S0, 0)))) &&
                         (!op_is_left_mergeable
                        (B_N_PKEY(S0, 0), S0->b_size)),
                         "vs-10280: item must be mergeable");
            }
      }

      return i;
}

/* CLEANING STOPPED HERE */

/* Shift shift_num (shift_bytes) items from S[0] to the right neighbor, and replace the delimiting key */
int leaf_shift_right(struct tree_balance *tb, int shift_num, int shift_bytes)
{
      //  struct buffer_head * S0 = PATH_PLAST_BUFFER (tb->tb_path);
      int ret_value;

      /* move shift_num (and shift_bytes) items from S[0] to right neighbor R[0] */
      ret_value =
          leaf_move_items(LEAF_FROM_S_TO_R, tb, shift_num, shift_bytes, NULL);

      /* replace rkey in CFR[0] by the 0-th key from R[0] */
      if (shift_num) {
            replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);

      }

      return ret_value;
}

static void leaf_delete_items_entirely(struct buffer_info *bi,
                               int first, int del_num);
/*  If del_bytes == -1, starting from position 'first' delete del_num items in whole in buffer CUR.
    If not. 
    If last_first == 0. Starting from position 'first' delete del_num-1 items in whole. Delete part of body of
    the first item. Part defined by del_bytes. Don't delete first item header
    If last_first == 1. Starting from position 'first+1' delete del_num-1 items in whole. Delete part of body of
    the last item . Part defined by del_bytes. Don't delete last item header.
*/
void leaf_delete_items(struct buffer_info *cur_bi, int last_first,
                   int first, int del_num, int del_bytes)
{
      struct buffer_head *bh;
      int item_amount = B_NR_ITEMS(bh = cur_bi->bi_bh);

      RFALSE(!bh, "10155: bh is not defined");
      RFALSE(del_num < 0, "10160: del_num can not be < 0. del_num==%d",
             del_num);
      RFALSE(first < 0
             || first + del_num > item_amount,
             "10165: invalid number of first item to be deleted (%d) or "
             "no so much items (%d) to delete (only %d)", first,
             first + del_num, item_amount);

      if (del_num == 0)
            return;

      if (first == 0 && del_num == item_amount && del_bytes == -1) {
            make_empty_node(cur_bi);
            do_balance_mark_leaf_dirty(cur_bi->tb, bh, 0);
            return;
      }

      if (del_bytes == -1)
            /* delete del_num items beginning from item in position first */
            leaf_delete_items_entirely(cur_bi, first, del_num);
      else {
            if (last_first == FIRST_TO_LAST) {
                  /* delete del_num-1 items beginning from item in position first  */
                  leaf_delete_items_entirely(cur_bi, first, del_num - 1);

                  /* delete the part of the first item of the bh
                     do not delete item header
                   */
                  leaf_cut_from_buffer(cur_bi, 0, 0, del_bytes);
            } else {
                  struct item_head *ih;
                  int len;

                  /* delete del_num-1 items beginning from item in position first+1  */
                  leaf_delete_items_entirely(cur_bi, first + 1,
                                       del_num - 1);

                  if (is_direntry_le_ih
                      (ih = B_N_PITEM_HEAD(bh, B_NR_ITEMS(bh) - 1)))
                        /* the last item is directory  */
                        /* len = numbers of directory entries in this item */
                        len = ih_entry_count(ih);
                  else
                        /* len = body len of item */
                        len = ih_item_len(ih);

                  /* delete the part of the last item of the bh 
                     do not delete item header
                   */
                  leaf_cut_from_buffer(cur_bi, B_NR_ITEMS(bh) - 1,
                                   len - del_bytes, del_bytes);
            }
      }
}

/* insert item into the leaf node in position before */
void leaf_insert_into_buf(struct buffer_info *bi, int before,
                    struct item_head *inserted_item_ih,
                    const char *inserted_item_body, int zeros_number)
{
      struct buffer_head *bh = bi->bi_bh;
      int nr, free_space;
      struct block_head *blkh;
      struct item_head *ih;
      int i;
      int last_loc, unmoved_loc;
      char *to;

      blkh = B_BLK_HEAD(bh);
      nr = blkh_nr_item(blkh);
      free_space = blkh_free_space(blkh);

      /* check free space */
      RFALSE(free_space < ih_item_len(inserted_item_ih) + IH_SIZE,
             "vs-10170: not enough free space in block %z, new item %h",
             bh, inserted_item_ih);
      RFALSE(zeros_number > ih_item_len(inserted_item_ih),
             "vs-10172: zero number == %d, item length == %d",
             zeros_number, ih_item_len(inserted_item_ih));

      /* get item new item must be inserted before */
      ih = B_N_PITEM_HEAD(bh, before);

      /* prepare space for the body of new item */
      last_loc = nr ? ih_location(&(ih[nr - before - 1])) : bh->b_size;
      unmoved_loc = before ? ih_location(ih - 1) : bh->b_size;

      memmove(bh->b_data + last_loc - ih_item_len(inserted_item_ih),
            bh->b_data + last_loc, unmoved_loc - last_loc);

      to = bh->b_data + unmoved_loc - ih_item_len(inserted_item_ih);
      memset(to, 0, zeros_number);
      to += zeros_number;

      /* copy body to prepared space */
      if (inserted_item_body)
            memmove(to, inserted_item_body,
                  ih_item_len(inserted_item_ih) - zeros_number);
      else
            memset(to, '\0', ih_item_len(inserted_item_ih) - zeros_number);

      /* insert item header */
      memmove(ih + 1, ih, IH_SIZE * (nr - before));
      memmove(ih, inserted_item_ih, IH_SIZE);

      /* change locations */
      for (i = before; i < nr + 1; i++) {
            unmoved_loc -= ih_item_len(&(ih[i - before]));
            put_ih_location(&(ih[i - before]), unmoved_loc);
      }

      /* sizes, free space, item number */
      set_blkh_nr_item(blkh, blkh_nr_item(blkh) + 1);
      set_blkh_free_space(blkh,
                      free_space - (IH_SIZE +
                                ih_item_len(inserted_item_ih)));
      do_balance_mark_leaf_dirty(bi->tb, bh, 1);

      if (bi->bi_parent) {
            struct disk_child *t_dc;
            t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
            put_dc_size(t_dc,
                      dc_size(t_dc) + (IH_SIZE +
                                   ih_item_len(inserted_item_ih)));
            do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
      }
}

/* paste paste_size bytes to affected_item_num-th item. 
   When item is a directory, this only prepare space for new entries */
void leaf_paste_in_buffer(struct buffer_info *bi, int affected_item_num,
                    int pos_in_item, int paste_size,
                    const char *body, int zeros_number)
{
      struct buffer_head *bh = bi->bi_bh;
      int nr, free_space;
      struct block_head *blkh;
      struct item_head *ih;
      int i;
      int last_loc, unmoved_loc;

      blkh = B_BLK_HEAD(bh);
      nr = blkh_nr_item(blkh);
      free_space = blkh_free_space(blkh);

      /* check free space */
      RFALSE(free_space < paste_size,
             "vs-10175: not enough free space: needed %d, available %d",
             paste_size, free_space);

#ifdef CONFIG_REISERFS_CHECK
      if (zeros_number > paste_size) {
            print_cur_tb("10177");
            reiserfs_panic(NULL,
                         "vs-10177: leaf_paste_in_buffer: ero number == %d, paste_size == %d",
                         zeros_number, paste_size);
      }
#endif                        /* CONFIG_REISERFS_CHECK */

      /* item to be appended */
      ih = B_N_PITEM_HEAD(bh, affected_item_num);

      last_loc = ih_location(&(ih[nr - affected_item_num - 1]));
      unmoved_loc = affected_item_num ? ih_location(ih - 1) : bh->b_size;

      /* prepare space */
      memmove(bh->b_data + last_loc - paste_size, bh->b_data + last_loc,
            unmoved_loc - last_loc);

      /* change locations */
      for (i = affected_item_num; i < nr; i++)
            put_ih_location(&(ih[i - affected_item_num]),
                        ih_location(&(ih[i - affected_item_num])) -
                        paste_size);

      if (body) {
            if (!is_direntry_le_ih(ih)) {
                  if (!pos_in_item) {
                        /* shift data to right */
                        memmove(bh->b_data + ih_location(ih) +
                              paste_size,
                              bh->b_data + ih_location(ih),
                              ih_item_len(ih));
                        /* paste data in the head of item */
                        memset(bh->b_data + ih_location(ih), 0,
                               zeros_number);
                        memcpy(bh->b_data + ih_location(ih) +
                               zeros_number, body,
                               paste_size - zeros_number);
                  } else {
                        memset(bh->b_data + unmoved_loc - paste_size, 0,
                               zeros_number);
                        memcpy(bh->b_data + unmoved_loc - paste_size +
                               zeros_number, body,
                               paste_size - zeros_number);
                  }
            }
      } else
            memset(bh->b_data + unmoved_loc - paste_size, '\0', paste_size);

      put_ih_item_len(ih, ih_item_len(ih) + paste_size);

      /* change free space */
      set_blkh_free_space(blkh, free_space - paste_size);

      do_balance_mark_leaf_dirty(bi->tb, bh, 0);

      if (bi->bi_parent) {
            struct disk_child *t_dc =
                B_N_CHILD(bi->bi_parent, bi->bi_position);
            put_dc_size(t_dc, dc_size(t_dc) + paste_size);
            do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
      }
}

/* cuts DEL_COUNT entries beginning from FROM-th entry. Directory item
   does not have free space, so it moves DEHs and remaining records as
   necessary. Return value is size of removed part of directory item
   in bytes. */
static int leaf_cut_entries(struct buffer_head *bh,
                      struct item_head *ih, int from, int del_count)
{
      char *item;
      struct reiserfs_de_head *deh;
      int prev_record_offset; /* offset of record, that is (from-1)th */
      char *prev_record;      /* */
      int cut_records_len;    /* length of all removed records */
      int i;

      /* make sure, that item is directory and there are enough entries to
         remove */
      RFALSE(!is_direntry_le_ih(ih), "10180: item is not directory item");
      RFALSE(I_ENTRY_COUNT(ih) < from + del_count,
             "10185: item contains not enough entries: entry_cout = %d, from = %d, to delete = %d",
             I_ENTRY_COUNT(ih), from, del_count);

      if (del_count == 0)
            return 0;

      /* first byte of item */
      item = bh->b_data + ih_location(ih);

      /* entry head array */
      deh = B_I_DEH(bh, ih);

      /* first byte of remaining entries, those are BEFORE cut entries
         (prev_record) and length of all removed records (cut_records_len) */
      prev_record_offset =
          (from ? deh_location(&(deh[from - 1])) : ih_item_len(ih));
      cut_records_len = prev_record_offset /*from_record */  -
          deh_location(&(deh[from + del_count - 1]));
      prev_record = item + prev_record_offset;

      /* adjust locations of remaining entries */
      for (i = I_ENTRY_COUNT(ih) - 1; i > from + del_count - 1; i--)
            put_deh_location(&(deh[i]),
                         deh_location(&deh[i]) -
                         (DEH_SIZE * del_count));

      for (i = 0; i < from; i++)
            put_deh_location(&(deh[i]),
                         deh_location(&deh[i]) - (DEH_SIZE * del_count +
                                            cut_records_len));

      put_ih_entry_count(ih, ih_entry_count(ih) - del_count);

      /* shift entry head array and entries those are AFTER removed entries */
      memmove((char *)(deh + from),
            deh + from + del_count,
            prev_record - cut_records_len - (char *)(deh + from +
                                           del_count));

      /* shift records, those are BEFORE removed entries */
      memmove(prev_record - cut_records_len - DEH_SIZE * del_count,
            prev_record, item + ih_item_len(ih) - prev_record);

      return DEH_SIZE * del_count + cut_records_len;
}

/*  when cut item is part of regular file
        pos_in_item - first byte that must be cut
        cut_size - number of bytes to be cut beginning from pos_in_item
 
   when cut item is part of directory
        pos_in_item - number of first deleted entry
        cut_size - count of deleted entries
    */
void leaf_cut_from_buffer(struct buffer_info *bi, int cut_item_num,
                    int pos_in_item, int cut_size)
{
      int nr;
      struct buffer_head *bh = bi->bi_bh;
      struct block_head *blkh;
      struct item_head *ih;
      int last_loc, unmoved_loc;
      int i;

      blkh = B_BLK_HEAD(bh);
      nr = blkh_nr_item(blkh);

      /* item head of truncated item */
      ih = B_N_PITEM_HEAD(bh, cut_item_num);

      if (is_direntry_le_ih(ih)) {
            /* first cut entry () */
            cut_size = leaf_cut_entries(bh, ih, pos_in_item, cut_size);
            if (pos_in_item == 0) {
                  /* change key */
                  RFALSE(cut_item_num,
                         "when 0-th enrty of item is cut, that item must be first in the node, not %d-th",
                         cut_item_num);
                  /* change item key by key of first entry in the item */
                  set_le_ih_k_offset(ih, deh_offset(B_I_DEH(bh, ih)));
                  /*memcpy (&ih->ih_key.k_offset, &(B_I_DEH (bh, ih)->deh_offset), SHORT_KEY_SIZE); */
            }
      } else {
            /* item is direct or indirect */
            RFALSE(is_statdata_le_ih(ih), "10195: item is stat data");
            RFALSE(pos_in_item && pos_in_item + cut_size != ih_item_len(ih),
                   "10200: invalid offset (%lu) or trunc_size (%lu) or ih_item_len (%lu)",
                   (long unsigned)pos_in_item, (long unsigned)cut_size,
                   (long unsigned)ih_item_len(ih));

            /* shift item body to left if cut is from the head of item */
            if (pos_in_item == 0) {
                  memmove(bh->b_data + ih_location(ih),
                        bh->b_data + ih_location(ih) + cut_size,
                        ih_item_len(ih) - cut_size);

                  /* change key of item */
                  if (is_direct_le_ih(ih))
                        set_le_ih_k_offset(ih,
                                       le_ih_k_offset(ih) +
                                       cut_size);
                  else {
                        set_le_ih_k_offset(ih,
                                       le_ih_k_offset(ih) +
                                       (cut_size / UNFM_P_SIZE) *
                                       bh->b_size);
                        RFALSE(ih_item_len(ih) == cut_size
                               && get_ih_free_space(ih),
                               "10205: invalid ih_free_space (%h)", ih);
                  }
            }
      }

      /* location of the last item */
      last_loc = ih_location(&(ih[nr - cut_item_num - 1]));

      /* location of the item, which is remaining at the same place */
      unmoved_loc = cut_item_num ? ih_location(ih - 1) : bh->b_size;

      /* shift */
      memmove(bh->b_data + last_loc + cut_size, bh->b_data + last_loc,
            unmoved_loc - last_loc - cut_size);

      /* change item length */
      put_ih_item_len(ih, ih_item_len(ih) - cut_size);

      if (is_indirect_le_ih(ih)) {
            if (pos_in_item)
                  set_ih_free_space(ih, 0);
      }

      /* change locations */
      for (i = cut_item_num; i < nr; i++)
            put_ih_location(&(ih[i - cut_item_num]),
                        ih_location(&ih[i - cut_item_num]) + cut_size);

      /* size, free space */
      set_blkh_free_space(blkh, blkh_free_space(blkh) + cut_size);

      do_balance_mark_leaf_dirty(bi->tb, bh, 0);

      if (bi->bi_parent) {
            struct disk_child *t_dc;
            t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
            put_dc_size(t_dc, dc_size(t_dc) - cut_size);
            do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
      }
}

/* delete del_num items from buffer starting from the first'th item */
static void leaf_delete_items_entirely(struct buffer_info *bi,
                               int first, int del_num)
{
      struct buffer_head *bh = bi->bi_bh;
      int nr;
      int i, j;
      int last_loc, last_removed_loc;
      struct block_head *blkh;
      struct item_head *ih;

      RFALSE(bh == NULL, "10210: buffer is 0");
      RFALSE(del_num < 0, "10215: del_num less than 0 (%d)", del_num);

      if (del_num == 0)
            return;

      blkh = B_BLK_HEAD(bh);
      nr = blkh_nr_item(blkh);

      RFALSE(first < 0 || first + del_num > nr,
             "10220: first=%d, number=%d, there is %d items", first, del_num,
             nr);

      if (first == 0 && del_num == nr) {
            /* this does not work */
            make_empty_node(bi);

            do_balance_mark_leaf_dirty(bi->tb, bh, 0);
            return;
      }

      ih = B_N_PITEM_HEAD(bh, first);

      /* location of unmovable item */
      j = (first == 0) ? bh->b_size : ih_location(ih - 1);

      /* delete items */
      last_loc = ih_location(&(ih[nr - 1 - first]));
      last_removed_loc = ih_location(&(ih[del_num - 1]));

      memmove(bh->b_data + last_loc + j - last_removed_loc,
            bh->b_data + last_loc, last_removed_loc - last_loc);

      /* delete item headers */
      memmove(ih, ih + del_num, (nr - first - del_num) * IH_SIZE);

      /* change item location */
      for (i = first; i < nr - del_num; i++)
            put_ih_location(&(ih[i - first]),
                        ih_location(&(ih[i - first])) + (j -
                                                 last_removed_loc));

      /* sizes, item number */
      set_blkh_nr_item(blkh, blkh_nr_item(blkh) - del_num);
      set_blkh_free_space(blkh,
                      blkh_free_space(blkh) + (j - last_removed_loc +
                                         IH_SIZE * del_num));

      do_balance_mark_leaf_dirty(bi->tb, bh, 0);

      if (bi->bi_parent) {
            struct disk_child *t_dc =
                B_N_CHILD(bi->bi_parent, bi->bi_position);
            put_dc_size(t_dc,
                      dc_size(t_dc) - (j - last_removed_loc +
                                   IH_SIZE * del_num));
            do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
      }
}

/* paste new_entry_count entries (new_dehs, records) into position before to item_num-th item */
void leaf_paste_entries(struct buffer_head *bh,
                  int item_num,
                  int before,
                  int new_entry_count,
                  struct reiserfs_de_head *new_dehs,
                  const char *records, int paste_size)
{
      struct item_head *ih;
      char *item;
      struct reiserfs_de_head *deh;
      char *insert_point;
      int i, old_entry_num;

      if (new_entry_count == 0)
            return;

      ih = B_N_PITEM_HEAD(bh, item_num);

      /* make sure, that item is directory, and there are enough records in it */
      RFALSE(!is_direntry_le_ih(ih), "10225: item is not directory item");
      RFALSE(I_ENTRY_COUNT(ih) < before,
             "10230: there are no entry we paste entries before. entry_count = %d, before = %d",
             I_ENTRY_COUNT(ih), before);

      /* first byte of dest item */
      item = bh->b_data + ih_location(ih);

      /* entry head array */
      deh = B_I_DEH(bh, ih);

      /* new records will be pasted at this point */
      insert_point =
          item +
          (before ? deh_location(&(deh[before - 1]))
           : (ih_item_len(ih) - paste_size));

      /* adjust locations of records that will be AFTER new records */
      for (i = I_ENTRY_COUNT(ih) - 1; i >= before; i--)
            put_deh_location(&(deh[i]),
                         deh_location(&(deh[i])) +
                         (DEH_SIZE * new_entry_count));

      /* adjust locations of records that will be BEFORE new records */
      for (i = 0; i < before; i++)
            put_deh_location(&(deh[i]),
                         deh_location(&(deh[i])) + paste_size);

      old_entry_num = I_ENTRY_COUNT(ih);
      put_ih_entry_count(ih, ih_entry_count(ih) + new_entry_count);

      /* prepare space for pasted records */
      memmove(insert_point + paste_size, insert_point,
            item + (ih_item_len(ih) - paste_size) - insert_point);

      /* copy new records */
      memcpy(insert_point + DEH_SIZE * new_entry_count, records,
             paste_size - DEH_SIZE * new_entry_count);

      /* prepare space for new entry heads */
      deh += before;
      memmove((char *)(deh + new_entry_count), deh,
            insert_point - (char *)deh);

      /* copy new entry heads */
      deh = (struct reiserfs_de_head *)((char *)deh);
      memcpy(deh, new_dehs, DEH_SIZE * new_entry_count);

      /* set locations of new records */
      for (i = 0; i < new_entry_count; i++) {
            put_deh_location(&(deh[i]),
                         deh_location(&(deh[i])) +
                         (-deh_location
                          (&(new_dehs[new_entry_count - 1])) +
                          insert_point + DEH_SIZE * new_entry_count -
                          item));
      }

      /* change item key if necessary (when we paste before 0-th entry */
      if (!before) {
            set_le_ih_k_offset(ih, deh_offset(new_dehs));
/*      memcpy (&ih->ih_key.k_offset, 
                   &new_dehs->deh_offset, SHORT_KEY_SIZE);*/
      }
#ifdef CONFIG_REISERFS_CHECK
      {
            int prev, next;
            /* check record locations */
            deh = B_I_DEH(bh, ih);
            for (i = 0; i < I_ENTRY_COUNT(ih); i++) {
                  next =
                      (i <
                       I_ENTRY_COUNT(ih) -
                       1) ? deh_location(&(deh[i + 1])) : 0;
                  prev = (i != 0) ? deh_location(&(deh[i - 1])) : 0;

                  if (prev && prev <= deh_location(&(deh[i])))
                        reiserfs_warning(NULL,
                                     "vs-10240: leaf_paste_entries: directory item (%h) corrupted (prev %a, cur(%d) %a)",
                                     ih, deh + i - 1, i, deh + i);
                  if (next && next >= deh_location(&(deh[i])))
                        reiserfs_warning(NULL,
                                     "vs-10250: leaf_paste_entries: directory item (%h) corrupted (cur(%d) %a, next %a)",
                                     ih, i, deh + i, deh + i + 1);
            }
      }
#endif

}

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