91 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			91 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * btree.h - NILFS B-tree.
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|  *
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|  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License as published by
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|  * the Free Software Foundation; either version 2 of the License, or
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|  * (at your option) any later version.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License
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|  * along with this program; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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|  *
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|  * Written by Koji Sato <koji@osrg.net>.
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|  */
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| 
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| #ifndef _NILFS_BTREE_H
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| #define _NILFS_BTREE_H
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| 
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| #include <linux/types.h>
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| #include <linux/buffer_head.h>
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| #include <linux/list.h>
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| #include <linux/nilfs2_fs.h>
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| #include "btnode.h"
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| #include "bmap.h"
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| 
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| struct nilfs_btree;
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| struct nilfs_btree_path;
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| 
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| /**
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|  * struct nilfs_btree_node - B-tree node
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|  * @bn_flags: flags
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|  * @bn_level: level
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|  * @bn_nchildren: number of children
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|  * @bn_pad: padding
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|  */
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| struct nilfs_btree_node {
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| 	__u8 bn_flags;
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| 	__u8 bn_level;
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| 	__le16 bn_nchildren;
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| 	__le32 bn_pad;
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| };
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| 
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| /* flags */
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| #define NILFS_BTREE_NODE_ROOT	0x01
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| 
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| /* level */
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| #define NILFS_BTREE_LEVEL_DATA		0
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| #define NILFS_BTREE_LEVEL_NODE_MIN	(NILFS_BTREE_LEVEL_DATA + 1)
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| #define NILFS_BTREE_LEVEL_MAX		14
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| 
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| /**
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|  * struct nilfs_btree - B-tree structure
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|  * @bt_bmap: bmap base structure
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|  */
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| struct nilfs_btree {
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| 	struct nilfs_bmap bt_bmap;
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| };
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| 
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| 
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| #define NILFS_BTREE_ROOT_SIZE		NILFS_BMAP_SIZE
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| #define NILFS_BTREE_ROOT_NCHILDREN_MAX					\
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| 	((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) /	\
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| 	 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
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| #define NILFS_BTREE_ROOT_NCHILDREN_MIN	0
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| #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE	(sizeof(__le64))
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| #define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize)			\
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| 	(((nodesize) - sizeof(struct nilfs_btree_node) -		\
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| 		NILFS_BTREE_NODE_EXTRA_PAD_SIZE) /			\
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| 	 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
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| #define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize)			\
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| 	((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1)
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| #define NILFS_BTREE_KEY_MIN	((__u64)0)
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| #define NILFS_BTREE_KEY_MAX	(~(__u64)0)
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| 
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| 
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| int nilfs_btree_path_cache_init(void);
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| void nilfs_btree_path_cache_destroy(void);
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| int nilfs_btree_init(struct nilfs_bmap *);
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| int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
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| 				   const __u64 *, const __u64 *, int);
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| void nilfs_btree_init_gc(struct nilfs_bmap *);
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| 
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| #endif	/* _NILFS_BTREE_H */
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