[mirror_ubuntu-artful-kernel.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.
 *
 * Written by Koji Sato.
 */

#ifndef _NILFS_BTREE_H
#define _NILFS_BTREE_H

#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/list.h>
#include <linux/nilfs2_ondisk.h>	/* nilfs_btree_node */
#include "btnode.h"
#include "bmap.h"

/**
 * struct nilfs_btree_path - A path on which B-tree operations are executed
 * @bp_bh: buffer head of node block
 * @bp_sib_bh: buffer head of sibling node block
 * @bp_index: index of child node
 * @bp_oldreq: ptr end request for old ptr
 * @bp_newreq: ptr alloc request for new ptr
 * @bp_op: rebalance operation
 */
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 */
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	*
4b420ab4	16	* Written by Koji Sato.
17c76b01 KS	17	*/
	18
	19	#ifndef _NILFS_BTREE_H
	20	#define _NILFS_BTREE_H
	21
	22	#include <linux/types.h>
	23	#include <linux/buffer_head.h>
	24	#include <linux/list.h>
e63e88bc	25	#include <linux/nilfs2_ondisk.h> /* nilfs_btree_node */
17c76b01 KS	26	#include "btnode.h"
	27	#include "bmap.h"
	28
41c88bd7 LH	29	/**
	30	* struct nilfs_btree_path - A path on which B-tree operations are executed
	31	* @bp_bh: buffer head of node block
	32	* @bp_sib_bh: buffer head of sibling node block
	33	* @bp_index: index of child node
	34	* @bp_oldreq: ptr end request for old ptr
	35	* @bp_newreq: ptr alloc request for new ptr
	36	* @bp_op: rebalance operation
	37	*/
	38	struct nilfs_btree_path {
	39	struct buffer_head *bp_bh;
	40	struct buffer_head *bp_sib_bh;
	41	int bp_index;
	42	union nilfs_bmap_ptr_req bp_oldreq;
	43	union nilfs_bmap_ptr_req bp_newreq;
	44	struct nilfs_btnode_chkey_ctxt bp_ctxt;
e7c274f8	45	void (bp_op)(struct nilfs_bmap , struct nilfs_btree_path *,
41c88bd7 LH	46	int, __u64 , __u64 );
41c88bd7 LH	47	};
17c76b01 KS	48
	49	#define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE
	50	#define NILFS_BTREE_ROOT_NCHILDREN_MAX \
	51	((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \
	52	(sizeof(__le64 /* dkey /) + sizeof(__le64 / dptr */)))
	53	#define NILFS_BTREE_ROOT_NCHILDREN_MIN 0
	54	#define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64))
	55	#define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \
	56	(((nodesize) - sizeof(struct nilfs_btree_node) - \
	57	NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \
	58	(sizeof(__le64 /* dkey /) + sizeof(__le64 / dptr */)))
	59	#define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \
	60	((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1)
	61	#define NILFS_BTREE_KEY_MIN ((__u64)0)
	62	#define NILFS_BTREE_KEY_MAX (~(__u64)0)
	63
41c88bd7	64	extern struct kmem_cache *nilfs_btree_path_cache;
17c76b01	65
3033342a	66	int nilfs_btree_init(struct nilfs_bmap *);
17c76b01	67	int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
3033342a	68	const __u64 , const __u64 , int);
17c76b01 KS	69	void nilfs_btree_init_gc(struct nilfs_bmap *);
17c76b01 KS	70
1d5385b9 RK	71	int nilfs_btree_broken_node_block(struct buffer_head *bh);
1d5385b9 RK	72
17c76b01	73	#endif /* _NILFS_BTREE_H */