/*
 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
 */

#include <linux/uaccess.h>
#include <linux/string.h>
#include <linux/time.h>
#include "reiserfs.h"
#include <linux/buffer_head.h>

/*
 * 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;
        /*
         * 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
         */
        int item_num_in_dest;

        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 = item_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,
                                                         leaf_key(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 < ih_entry_count(ih)) {
                                set_le_ih_k_offset(&new_ih,
                                                   deh_offset(&deh[from]));
                        } 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, item_num_in_dest,
                           (last_first ==
                            FIRST_TO_LAST) ? ih_entry_count(item_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;
        /* number of items in the source and destination buffers */
        int dest_nr_item, src_nr_item;
        struct item_head *ih;
        struct item_head *dih;

        dest_nr_item = B_NR_ITEMS(dest);

        /*
         * 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
         */
        if (last_first == FIRST_TO_LAST) {
                ih = item_head(src, 0);
                dih = item_head(dest, dest_nr_item - 1);

                /* there is nothing to merge */
                if (!dest_nr_item
                    || (!op_is_left_mergeable(&ih->ih_key, src->b_size)))
                        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(sb_from_bi(dest_bi),
                                                       "vs-10020",
                                                       "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, ih_item_body(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 = item_head(src, src_nr_item - 1);
        dih = item_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)) {
                /*
                 * bytes_or_entries = entries number in last
                 * item body of SOURCE
                 */
                if (bytes_or_entries == -1)
                        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,
                             ih_item_body(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 = item_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, item_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,
               item_body(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 )
                 */
                ih = item_head(src, item_num);
                if (is_direntry_le_ih(ih))
                        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,
                                             item_body(src, item_num), 0);
                }
        } else {
                /*
                 * if ( if item in position item_num in buffer
                 * SOURCE is directory item )
                 */
                ih = item_head(src, item_num);
                if (is_direntry_le_ih(ih))
                        leaf_copy_dir_entries(dest_bi, src, LAST_TO_FIRST,
                                              item_num,
                                              ih_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_key, &ih->ih_key, KEY_SIZE);

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

                        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);

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

                        leaf_insert_into_buf(dest_bi, 0, &n_ih,
                                             item_body(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->b_item_order */
                src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 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_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(sb_from_bi(src_bi), "vs-10250",
                               "shift type is unknown (%d)", shift_mode);
        }
        RFALSE(!src_bi->bi_bh || !dest_bi->bi_bh,
               "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) {
                /* number of items in S[0] == 0 */
                if (B_NR_ITEMS(S0) == 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",
                                               "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(item_head(S0, 0))
                                  && !ih_entry_count(item_head(S0, 0)))) &&
                               (!op_is_left_mergeable
                                (leaf_key(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)
{
        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);

                        ih = item_head(bh, B_NR_ITEMS(bh) - 1);
                        if (is_direntry_le_ih(ih))
                                /* 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 * const inserted_item_ih,
                          const char * const 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 = item_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) {
                struct super_block *sb = NULL;

                if (bi && bi->tb)
                        sb = bi->tb->tb_sb;
                print_cur_tb("10177");
                reiserfs_panic(sb, "vs-10177",
                               "zeros_number == %d, paste_size == %d",
                               zeros_number, paste_size);
        }
#endif                          /* CONFIG_REISERFS_CHECK */

        /* item to be appended */
        ih = item_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(ih_entry_count(ih) < from + del_count,
               "10185: item contains not enough entries: entry_count = %d, from = %d, to delete = %d",
               ih_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 = ih_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 = item_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)));
                }
        } 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 = item_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_info *bi,
                        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;
        struct buffer_head *bh = bi->bi_bh;

        if (new_entry_count == 0)
                return;

        ih = item_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(ih_entry_count(ih) < before,
               "10230: there are no entry we paste entries before. entry_count = %d, before = %d",
               ih_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 = ih_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 = ih_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));
        }
#ifdef CONFIG_REISERFS_CHECK
        {
                int prev, next;
                /* check record locations */
                deh = B_I_DEH(bh, ih);
                for (i = 0; i < ih_entry_count(ih); i++) {
                        next =
                            (i <
                             ih_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_error(sb_from_bi(bi), "vs-10240",
                                               "directory item (%h) "
                                               "corrupted (prev %a, "
                                               "cur(%d) %a)",
                                               ih, deh + i - 1, i, deh + i);
                        if (next && next >= deh_location(&deh[i]))
                                reiserfs_error(sb_from_bi(bi), "vs-10250",
                                               "directory item (%h) "
                                               "corrupted (cur(%d) %a, "
                                               "next %a)",
                                               ih, i, deh + i, deh + i + 1);
                }
        }
#endif

}