btree.h

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/*
 * btree.h - NILFS B-tree.
 *
 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Written by Koji Sato <[email protected]>.
 */

#ifndef _NILFS_BTREE_H
#define _NILFS_BTREE_H

#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/list.h>
#include <linux/nilfs2_fs.h>
#include "btnode.h"
#include "bmap.h"

struct nilfs_btree_path {
    struct buffer_head *bp_bh;
    struct buffer_head *bp_sib_bh;
    int bp_index;
    union nilfs_bmap_ptr_req bp_oldreq;
    union nilfs_bmap_ptr_req bp_newreq;
    struct nilfs_btnode_chkey_ctxt bp_ctxt;
    void (*bp_op)(struct nilfs_bmap *, struct nilfs_btree_path *,
              int, __u64 *, __u64 *);
};

#define NILFS_BTREE_ROOT_SIZE       NILFS_BMAP_SIZE
#define NILFS_BTREE_ROOT_NCHILDREN_MAX                  \
    ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) /    \
     (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
#define NILFS_BTREE_ROOT_NCHILDREN_MIN  0
#define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64))
#define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize)            \
    (((nodesize) - sizeof(struct nilfs_btree_node) -        \
        NILFS_BTREE_NODE_EXTRA_PAD_SIZE) /          \
     (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
#define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize)            \
    ((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1)
#define NILFS_BTREE_KEY_MIN ((__u64)0)
#define NILFS_BTREE_KEY_MAX (~(__u64)0)

extern struct kmem_cache *nilfs_btree_path_cache;

int nilfs_btree_init(struct nilfs_bmap *);
int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
                   const __u64 *, const __u64 *, int);
void nilfs_btree_init_gc(struct nilfs_bmap *);

int nilfs_btree_broken_node_block(struct buffer_head *bh);

#endif  /* _NILFS_BTREE_H */