[linux-block.git] / fs / nilfs2 / btree.h

/*
 * 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 <koji@osrg.net>.
 */

#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;
struct nilfs_btree_path;

/**
 * struct nilfs_btree_node - B-tree node
 * @bn_flags: flags
 * @bn_level: level
 * @bn_nchildren: number of children
 * @bn_pad: padding
 */
struct nilfs_btree_node {
	__u8 bn_flags;
	__u8 bn_level;
	__le16 bn_nchildren;
	__le32 bn_pad;
};

/* flags */
#define NILFS_BTREE_NODE_ROOT	0x01

/* level */
#define NILFS_BTREE_LEVEL_DATA		0
#define NILFS_BTREE_LEVEL_NODE_MIN	(NILFS_BTREE_LEVEL_DATA + 1)
#define NILFS_BTREE_LEVEL_MAX		14

/**
 * struct nilfs_btree - B-tree structure
 * @bt_bmap: bmap base structure
 */
struct nilfs_btree {
	struct nilfs_bmap bt_bmap;
};


#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)


int nilfs_btree_path_cache_init(void);
void nilfs_btree_path_cache_destroy(void);
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 *);

#endif	/* _NILFS_BTREE_H */
Commit	Line	Data
17c76b01 KS	1	/*
	2	* btree.h - NILFS B-tree.
	3	*
	4	* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*
	20	* Written by Koji Sato <koji@osrg.net>.
	21	*/
	22
	23	#ifndef _NILFS_BTREE_H
	24	#define _NILFS_BTREE_H
	25
	26	#include <linux/types.h>
	27	#include <linux/buffer_head.h>
	28	#include <linux/list.h>
	29	#include <linux/nilfs2_fs.h>
	30	#include "btnode.h"
	31	#include "bmap.h"
	32
	33	struct nilfs_btree;
	34	struct nilfs_btree_path;
	35
17c76b01 KS	36	/**
	37	* struct nilfs_btree_node - B-tree node
	38	* @bn_flags: flags
	39	* @bn_level: level
	40	* @bn_nchildren: number of children
	41	* @bn_pad: padding
	42	*/
	43	struct nilfs_btree_node {
	44	__u8 bn_flags;
	45	__u8 bn_level;
	46	__le16 bn_nchildren;
	47	__le32 bn_pad;
	48	};
	49
	50	/* flags */
	51	#define NILFS_BTREE_NODE_ROOT 0x01
	52
	53	/* level */
	54	#define NILFS_BTREE_LEVEL_DATA 0
	55	#define NILFS_BTREE_LEVEL_NODE_MIN (NILFS_BTREE_LEVEL_DATA + 1)
	56	#define NILFS_BTREE_LEVEL_MAX 14
	57
	58	/**
	59	* struct nilfs_btree - B-tree structure
	60	* @bt_bmap: bmap base structure
17c76b01 KS	61	*/
	62	struct nilfs_btree {
	63	struct nilfs_bmap bt_bmap;
17c76b01 KS	64	};
	65
	66
	67	#define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE
	68	#define NILFS_BTREE_ROOT_NCHILDREN_MAX \
	69	((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \
	70	(sizeof(__le64 /* dkey /) + sizeof(__le64 / dptr */)))
	71	#define NILFS_BTREE_ROOT_NCHILDREN_MIN 0
	72	#define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64))
	73	#define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \
	74	(((nodesize) - sizeof(struct nilfs_btree_node) - \
	75	NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \
	76	(sizeof(__le64 /* dkey /) + sizeof(__le64 / dptr */)))
	77	#define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \
	78	((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1)
	79	#define NILFS_BTREE_KEY_MIN ((__u64)0)
	80	#define NILFS_BTREE_KEY_MAX (~(__u64)0)
	81
	82
	83	int nilfs_btree_path_cache_init(void);
	84	void nilfs_btree_path_cache_destroy(void);
3033342a	85	int nilfs_btree_init(struct nilfs_bmap *);
17c76b01	86	int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
3033342a	87	const __u64 , const __u64 , int);
17c76b01 KS	88	void nilfs_btree_init_gc(struct nilfs_bmap *);
	89
	90	#endif /* _NILFS_BTREE_H */