/* * Copyright 1996-2003 by Hans Reiser, licensing governed by * reiserfsprogs/README */ #include "includes.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 */ extern struct tree_balance init_tb; extern int init_item_pos; extern int init_pos_in_item; extern int init_mode; /* copy copy_count entries from source directory item to dest buffer (creating new item if needed) */ static void leaf_copy_dir_entries (reiserfs_filsys_t * fs, 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); /* 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 ? get_deh_location (&deh[from - 1]) : get_ih_item_len (ih)) - get_deh_location (&deh[from + copy_count - 1]); records = source->b_data + get_ih_location (ih) + get_deh_location (&deh[from + copy_count - 1]); } else { copy_records_len = 0; records = 0; } /* 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 && are_items_mergeable (B_N_PITEM_HEAD (dest, item_num_in_dest), ih, dest->b_size) == 0) || (last_first == LAST_TO_FIRST && are_items_mergeable (ih, B_N_PITEM_HEAD (dest, item_num_in_dest), dest->b_size) == 0)) { /* create new item in dest */ struct item_head new_ih; /* form item header */ memcpy (&new_ih.ih_key, &ih->ih_key, KEY_SIZE); /* calculate item len */ set_ih_item_len (&new_ih, DEH_SIZE * copy_count + copy_records_len); set_ih_entry_count (&new_ih, 0); if (last_first == LAST_TO_FIRST) { /* form key by the following way */ if (from < get_ih_entry_count (ih)) { set_key_offset_v1 (&new_ih.ih_key, get_deh_offset (&deh[from])); } else { /* no entries will be copied to this item in this function */ set_key_offset_v1 (&new_ih.ih_key, MAX_KEY1_OFFSET); } set_key_uniqueness (&new_ih.ih_key, DIRENTRY_UNIQUENESS); } set_ih_key_format (&new_ih, get_ih_key_format (ih)); set_ih_flags (&new_ih, get_ih_flags (ih)); /* insert item into dest buffer */ leaf_insert_into_buf (fs, 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 (fs, dest_bi, (last_first == FIRST_TO_LAST) ? (B_NR_ITEMS(dest) - 1) : 0, 0xffff /*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) ? get_ih_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 (reiserfs_filsys_t * fs, 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 || (are_items_mergeable (dih, ih, src->b_size) == 0)) /* there is nothing to merge */ return 0; if ( I_IS_DIRECTORY_ITEM(ih) ) { if ( bytes_or_entries == -1 ) /* copy all entries to dest */ bytes_or_entries = get_ih_entry_count(ih); leaf_copy_dir_entries (fs, 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 = get_ih_item_len (ih); /* 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 (fs, dest_bi, dest_nr_item - 1, get_ih_item_len (dih), bytes_or_entries, B_I_PITEM(src,ih), 0); if (I_IS_INDIRECT_ITEM(dih)) { if (bytes_or_entries == get_ih_item_len (ih)) //dih->u.ih_free_space = ih->u.ih_free_space; 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 || are_items_mergeable (ih, dih, src->b_size) == 0) return 0; if ( I_IS_DIRECTORY_ITEM(ih)) { if ( bytes_or_entries == -1 ) /* bytes_or_entries = entries number in last item body of SOURCE */ bytes_or_entries = get_ih_entry_count(ih); leaf_copy_dir_entries (fs, dest_bi, src, LAST_TO_FIRST, src_nr_item - 1, get_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 */ if ( bytes_or_entries == -1 ) { /* bytes_or_entries = length of last item body of SOURCE */ bytes_or_entries = get_ih_item_len (ih); /* change first item key of the DEST */ //dih->ih_key.k_offset = ih->ih_key.k_offset; set_offset (key_format (&dih->ih_key), &dih->ih_key, get_offset (&ih->ih_key)); /* item becomes non-mergeable */ /* or mergeable if left item was */ //dih->ih_key.k_uniqueness = ih->ih_key.k_uniqueness; set_type (key_format (&dih->ih_key), &dih->ih_key, get_type (&ih->ih_key)); } else { /* merge to right only part of item */ /* change first item key of the DEST */ if ( I_IS_DIRECT_ITEM(dih) ) { //dih->ih_key.k_offset -= bytes_or_entries; set_offset (key_format (&dih->ih_key), &dih->ih_key, get_offset (&dih->ih_key) - bytes_or_entries); } else { //dih->ih_key.k_offset -= ((bytes_or_entries/UNFM_P_SIZE)*dest->b_size); set_offset (key_format (&dih->ih_key), &dih->ih_key, get_offset (&dih->ih_key) - ((bytes_or_entries/UNFM_P_SIZE)*dest->b_size)); } } leaf_paste_in_buffer (fs, dest_bi, 0, 0, bytes_or_entries, B_I_PITEM(src,ih) + get_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 (reiserfs_filsys_t * fs, struct buffer_info * dest_bi, struct buffer_head * src, int last_first, int first, int cpy_num) { struct buffer_head * dest; int nr; int dest_before; int last_loc, last_inserted_loc, location; int i, j; struct block_head * blkh; struct item_head * ih; dest = dest_bi->bi_bh; if (cpy_num == 0) return; blkh = B_BLK_HEAD(dest); nr = get_blkh_nr_items (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); /* 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); set_blkh_free_space (blkh, get_blkh_free_space (blkh) - IH_SIZE * cpy_num); /* location of unmovable item */ j = location = (dest_before == 0) ? dest->b_size : get_ih_location (ih-1); for (i = dest_before; i < nr + cpy_num; i ++) { location -= get_ih_item_len (&ih[i-dest_before]); set_ih_location (&ih[i-dest_before], location); } /* prepare space for items */ last_loc = get_ih_location (&ih[nr+cpy_num-1-dest_before]); last_inserted_loc = get_ih_location (&ih[cpy_num-1]); /* check free space */ 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_items (blkh, get_blkh_nr_items (blkh) + cpy_num); set_blkh_free_space (blkh, get_blkh_free_space (blkh) - (j - last_inserted_loc)); mark_buffer_dirty (dest); if (dest_bi->bi_parent) { struct disk_child * dc; dc = B_N_CHILD (dest_bi->bi_parent, dest_bi->bi_position); set_dc_child_size (dc, get_dc_child_size (dc) + j - last_inserted_loc + IH_SIZE * cpy_num); mark_buffer_dirty(dest_bi->bi_parent); } } /* This function splits the (liquid) item into two items (useful when shifting part of an item into another node.) */ static void leaf_item_bottle (reiserfs_filsys_t * fs, 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; if ( last_first == FIRST_TO_LAST ) { /* if ( if item in position item_num in buffer SOURCE is directory item ) */ if (I_IS_DIRECTORY_ITEM(ih = B_N_PITEM_HEAD(src,item_num))) leaf_copy_dir_entries (fs, 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); set_ih_item_len (&n_ih, cpy_bytes); if (I_IS_INDIRECT_ITEM(ih)) { //n_ih.u.ih_free_space = 0; set_ih_free_space (&n_ih, 0);; } //n_ih.ih_version = ih->ih_version; set_ih_key_format (&n_ih, get_ih_key_format (ih)); set_ih_flags (&n_ih, get_ih_flags (ih)); leaf_insert_into_buf (fs, 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 (I_IS_DIRECTORY_ITEM(ih = B_N_PITEM_HEAD (src, item_num))) leaf_copy_dir_entries (fs, dest_bi, src, LAST_TO_FIRST, item_num, get_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, SHORT_KEY_SIZE); if (I_IS_DIRECT_ITEM(ih)) { //n_ih.ih_key.k_offset = ih->ih_key.k_offset + ih->ih_item_len - cpy_bytes; set_offset (key_format (&ih->ih_key), &n_ih.ih_key, get_offset (&ih->ih_key) + get_ih_item_len (ih) - cpy_bytes); //n_ih.ih_key.k_uniqueness = TYPE_DIRECT; set_type (key_format (&ih->ih_key), &n_ih.ih_key, TYPE_DIRECT); //n_ih.u.ih_free_space = USHRT_MAX; set_ih_free_space (&n_ih, USHRT_MAX); } else { /* indirect item */ //n_ih.ih_key.k_offset = ih->ih_key.k_offset + (ih->ih_item_len - cpy_bytes) / UNFM_P_SIZE * dest->b_size; set_offset (key_format (&ih->ih_key), &n_ih.ih_key, get_offset (&ih->ih_key) + (get_ih_item_len (ih) - cpy_bytes) / UNFM_P_SIZE * dest->b_size); //n_ih.ih_key.k_uniqueness = TYPE_INDIRECT; set_type (key_format (&ih->ih_key), &n_ih.ih_key, TYPE_INDIRECT); //n_ih.u.ih_free_space = ih->u.ih_free_space; set_ih_free_space (&n_ih, get_ih_free_space (ih)); } /* set item length */ set_ih_item_len (&n_ih, cpy_bytes); //n_ih.ih_version = ih->ih_version; set_ih_key_format (&n_ih, get_ih_key_format (ih)); set_ih_flags (&n_ih, get_ih_flags (ih)); leaf_insert_into_buf (fs, dest_bi, 0, &n_ih, B_N_PITEM(src,item_num) + get_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 (reiserfs_filsys_t * fs, 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; 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 (fs, 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(fs, 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(fs, 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 (fs, 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 (fs, 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(fs, 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(fs, 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 (fs, 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) { /* 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->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->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->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->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->bi_bh = tb->R[0]; src_bi->bi_parent = tb->FR[0]; src_bi->bi_position = get_right_neighbor_position (tb, 0); 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->bi_bh = tb->L[0]; src_bi->bi_parent = tb->FL[0]; src_bi->bi_position = get_left_neighbor_position (tb, 0); 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->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->bi_bh = Snew; dest_bi->bi_parent = 0; dest_bi->bi_position = 0; *first_last = LAST_TO_FIRST; break; default: reiserfs_panic (0, "vs-10250: leaf_define_dest_src_infos: shift type is unknown (%d)", shift_mode); } } /* 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 (tb->tb_fs, &dest_bi, src_bi.bi_bh, first_last, mov_num, mov_bytes); leaf_delete_items (tb->tb_fs, &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, 0); if ( shift_num ) { if (B_NR_ITEMS (S0) == 0) { /* everything is moved from S[0] */ if (PATH_H_POSITION (tb->tb_path, 1) == 0) replace_key(tb->tb_fs, 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_fs, tb->CFL[0], tb->lkey[0], S0, 0); } } 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, 0); /* replace rkey in CFR[0] by the 0-th key from R[0] */ if (shift_num) { replace_key(tb->tb_fs, tb->CFR[0], tb->rkey[0], tb->R[0], 0); } return ret_value; } static void leaf_delete_items_entirely (reiserfs_filsys_t * sb, /*struct reiserfs_transaction_handle *th,*/ 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 (reiserfs_filsys_t * fs, 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); if ( del_num == 0 ) return; if ( first == 0 && del_num == item_amount && del_bytes == -1 ) { make_empty_node (cur_bi); mark_buffer_dirty (bh); return; } if ( del_bytes == -1 ) /* delete del_num items beginning from item in position first */ leaf_delete_items_entirely (fs, 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 (fs, 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 (fs, 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 (fs, cur_bi, first+1, del_num-1); if (I_IS_DIRECTORY_ITEM(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 = get_ih_entry_count(ih); else /* len = body len of item */ len = get_ih_item_len (ih); /* delete the part of the last item of the bh do not delete item header */ leaf_cut_from_buffer (fs, 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 (reiserfs_filsys_t * s, 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; struct block_head * blkh; struct item_head * ih; int i; int last_loc, unmoved_loc; char * to; blkh = B_BLK_HEAD (bh); nr = get_blkh_nr_items (blkh); /* 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 ? get_ih_location (&ih[nr - before - 1]) : bh->b_size; unmoved_loc = before ? get_ih_location (ih-1) : bh->b_size; memmove (bh->b_data + last_loc - get_ih_item_len (inserted_item_ih), bh->b_data + last_loc, unmoved_loc - last_loc); to = bh->b_data + unmoved_loc - get_ih_item_len (inserted_item_ih); memset (to, 0, zeros_number); to += zeros_number; /* copy body to prepared space */ if (inserted_item_body) //if (mem_mode == REISERFS_USER_MEM) // copy_from_user (to, inserted_item_body, inserted_item_ih->ih_item_len - zeros_number); //else { memmove (to, inserted_item_body, get_ih_item_len (inserted_item_ih) - zeros_number); //} else memset(to, '\0', get_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 -= get_ih_item_len (&ih[i-before]); set_ih_location (&ih[i-before], unmoved_loc); } /* sizes, free space, item number */ set_blkh_nr_items (blkh, get_blkh_nr_items (blkh) + 1); set_blkh_free_space (blkh, get_blkh_free_space (blkh) - (IH_SIZE + get_ih_item_len (inserted_item_ih))); mark_buffer_dirty(bh) ; if (bi->bi_parent) { struct disk_child * dc; dc = B_N_CHILD (bi->bi_parent, bi->bi_position); set_dc_child_size (dc, get_dc_child_size (dc) + IH_SIZE + get_ih_item_len (inserted_item_ih)); mark_buffer_dirty(bi->bi_parent) ; } if (is_a_leaf(bh->b_data, bh->b_size) != THE_LEAF) reiserfs_panic ("leaf_insert_into_buf: bad leaf %lu: %b", bh->b_blocknr, bh); } /* 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 (reiserfs_filsys_t * fs, 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; struct block_head * blkh; struct item_head * ih; int i; int last_loc, unmoved_loc; blkh = B_BLK_HEAD (bh); nr = get_blkh_nr_items (blkh); /* item to be appended */ ih = B_N_PITEM_HEAD(bh, affected_item_num); last_loc = get_ih_location (&ih[nr - affected_item_num - 1]); unmoved_loc = affected_item_num ? get_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 ++) set_ih_location (&ih[i-affected_item_num], get_ih_location (&ih[i-affected_item_num]) - paste_size); if ( body ) { if (!I_IS_DIRECTORY_ITEM(ih)) { //if (mem_mode == REISERFS_USER_MEM) { //memset (bh->b_data + unmoved_loc - paste_size, 0, zeros_number); //copy_from_user (bh->b_data + unmoved_loc - paste_size + zeros_number, body, paste_size - zeros_number); //} else { if (!pos_in_item) { /* shift data to right */ memmove (bh->b_data + get_ih_location (ih) + paste_size, bh->b_data + get_ih_location (ih), get_ih_item_len (ih)); /* paste data in the head of item */ memset (bh->b_data + get_ih_location (ih), 0, zeros_number); memcpy (bh->b_data + get_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); set_ih_item_len (ih, get_ih_item_len (ih) + paste_size); /* change free space */ set_blkh_free_space (blkh, get_blkh_free_space (blkh) - paste_size); mark_buffer_dirty(bh) ; if (bi->bi_parent) { struct disk_child * dc; dc = B_N_CHILD (bi->bi_parent, bi->bi_position); set_dc_child_size (dc, get_dc_child_size (dc) + paste_size); mark_buffer_dirty(bi->bi_parent); } if (is_a_leaf(bh->b_data, bh->b_size) != THE_LEAF) reiserfs_panic ("leaf_paste_in_buffer: bad leaf %lu: %b", bh->b_blocknr, bh); } /* 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; int entry_count; /* first byte of item */ item = B_I_PITEM (bh, ih); /* entry head array */ deh = B_I_DEH (bh, ih); entry_count = get_ih_entry_count (ih); if (del_count == 0) { int shift; int last_location; last_location = get_deh_location (deh + entry_count - 1); shift = last_location - DEH_SIZE * entry_count; memmove (deh + entry_count, item + last_location, get_ih_item_len (ih) - last_location); for (i = 0; i < entry_count; i ++) set_deh_location (&deh[i], get_deh_location (&deh[i]) - shift); return shift; } /* 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 ? get_deh_location (&deh[from - 1]) : get_ih_item_len (ih)); cut_records_len = prev_record_offset/*from_record*/ - get_deh_location (&deh[from + del_count - 1]); prev_record = item + prev_record_offset; /* adjust locations of remaining entries */ for (i = get_ih_entry_count (ih) - 1; i > from + del_count - 1; i --) { set_deh_location (deh + i, get_deh_location (deh + i) - (DEH_SIZE * del_count)); } for (i = 0; i < from; i ++) { set_deh_location (deh + i, get_deh_location (deh + i) - (DEH_SIZE * del_count + cut_records_len)); } set_ih_entry_count (ih, get_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 + get_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 (reiserfs_filsys_t * fs, 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 = get_blkh_nr_items (blkh); /* item head of truncated item */ ih = B_N_PITEM_HEAD (bh, cut_item_num); if (I_IS_DIRECTORY_ITEM (ih)) { /* first cut entry ()*/ cut_size = leaf_cut_entries (bh, ih, pos_in_item, cut_size); if (pos_in_item == 0) { /* change item key by key of first entry in the item */ set_key_offset_v1 (&ih->ih_key, get_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 */ /* shift item body to left if cut is from the head of item */ if (pos_in_item == 0) { memmove (bh->b_data + get_ih_location (ih), bh->b_data + get_ih_location (ih) + cut_size, get_ih_item_len (ih) - cut_size); /* change key of item */ if (I_IS_DIRECT_ITEM(ih)) { //ih->ih_key.k_offset += cut_size; set_offset (key_format (&ih->ih_key), &ih->ih_key, get_offset (&ih->ih_key) + cut_size); } else { //ih->ih_key.k_offset += (cut_size / UNFM_P_SIZE) * bh->b_size; set_offset (key_format (&ih->ih_key), &ih->ih_key, get_offset (&ih->ih_key) + (cut_size / UNFM_P_SIZE) * bh->b_size); } } } /* location of the last item */ last_loc = get_ih_location (&ih[nr - cut_item_num - 1]); /* location of the item, which is remaining at the same place */ unmoved_loc = cut_item_num ? get_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 */ set_ih_item_len (ih, get_ih_item_len (ih) - cut_size); if (I_IS_INDIRECT_ITEM(ih)) { if (pos_in_item) //ih->u.ih_free_space = 0; set_ih_free_space (ih, 0); } /* change locations */ for (i = cut_item_num; i < nr; i ++) { set_ih_location (&ih[i-cut_item_num], get_ih_location (&ih[i-cut_item_num]) + cut_size); } /* size, free space */ set_blkh_free_space (blkh, get_blkh_free_space (blkh) + cut_size); mark_buffer_dirty(bh); if (bi->bi_parent) { struct disk_child * dc; dc = B_N_CHILD (bi->bi_parent, bi->bi_position); set_dc_child_size (dc, get_dc_child_size (dc) - cut_size); mark_buffer_dirty(bi->bi_parent); } if (is_a_leaf(bh->b_data, bh->b_size) != THE_LEAF) reiserfs_panic ("leaf_cut_from_buffer: bad leaf %lu: %b", bh->b_blocknr, bh); } /* delete del_num items from buffer starting from the first'th item */ static void leaf_delete_items_entirely (reiserfs_filsys_t * fs, 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; if (del_num == 0) return; blkh = B_BLK_HEAD (bh); nr = get_blkh_nr_items (blkh); if (first == 0 && del_num == nr) { /* this does not work */ make_empty_node (bi); mark_buffer_dirty(bh); return; } ih = B_N_PITEM_HEAD (bh, first); /* location of unmovable item */ j = (first == 0) ? bh->b_size : get_ih_location (ih-1); /* delete items */ last_loc = get_ih_location (&ih[nr - 1 - first]); last_removed_loc = get_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 ++) { set_ih_location (&ih[i-first], get_ih_location (&ih[i-first]) + j - last_removed_loc); } /* sizes, item number */ set_blkh_nr_items (blkh, get_blkh_nr_items (blkh)/*nr*/ - del_num); set_blkh_free_space (blkh, get_blkh_free_space (blkh) + j - last_removed_loc + IH_SIZE * del_num); mark_buffer_dirty(bh); if (bi->bi_parent) { struct disk_child * dc; dc = B_N_CHILD (bi->bi_parent, bi->bi_position); set_dc_child_size (dc, get_dc_child_size (dc) - (j - last_removed_loc + IH_SIZE * del_num)); mark_buffer_dirty(bi->bi_parent); } if (is_a_leaf(bh->b_data, bh->b_size) != THE_LEAF) reiserfs_panic ("leaf_delete_items_entirely: bad leaf %lu: %b", bh->b_blocknr, bh); } /* 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); /* first byte of dest item */ item = B_I_PITEM (bh, ih); /* entry head array */ deh = B_I_DEH (bh, ih); /* new records will be pasted at this point */ insert_point = item + (before ? get_deh_location (&deh[before - 1]) : (get_ih_item_len (ih) - paste_size)); /* adjust locations of records that will be AFTER new records */ for (i = get_ih_entry_count (ih) - 1; i >= before; i --) set_deh_location (deh + i, get_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 ++) set_deh_location (deh + i, get_deh_location (deh + i) + paste_size); old_entry_num = get_ih_entry_count (ih); //I_ENTRY_COUNT(ih) += new_entry_count; set_ih_entry_count (ih, old_entry_num + new_entry_count); /* prepare space for pasted records */ memmove (insert_point + paste_size, insert_point, item + (get_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 */ memcpy (deh, new_dehs, DEH_SIZE * new_entry_count); /* set locations of new records */ for (i = 0; i < new_entry_count; i ++) set_deh_location (deh + i, get_deh_location (deh + i) + (- get_deh_location (&new_dehs[new_entry_count - 1]) + insert_point + DEH_SIZE * new_entry_count - item)); /* change item key if neccessary (when we paste before 0-th entry */ if (!before) set_key_offset_v1 (&ih->ih_key, get_deh_offset (new_dehs)); } /* wrappers for operations on one separated node */ void delete_item (reiserfs_filsys_t * fs, struct buffer_head * bh, int item_num) { struct buffer_info bi; bi.bi_bh = bh; bi.bi_parent = 0; bi.bi_position = 0; leaf_delete_items_entirely (fs, &bi, item_num, 1); } void cut_entry (reiserfs_filsys_t * fs, struct buffer_head * bh, int item_num, int entry_num, int del_count) { struct buffer_info bi; bi.bi_bh = bh; bi.bi_parent = 0; bi.bi_position = 0; leaf_cut_from_buffer (fs, &bi, item_num, entry_num, del_count); }