xref: /linux/fs/nilfs2/btree.h (revision ae98043f5f7fa45b65084f70e3ada3209873ebb4)
1*ae98043fSRyusuke Konishi /* SPDX-License-Identifier: GPL-2.0+ */
217c76b01SKoji Sato /*
317c76b01SKoji Sato  * btree.h - NILFS B-tree.
417c76b01SKoji Sato  *
517c76b01SKoji Sato  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
617c76b01SKoji Sato  *
74b420ab4SRyusuke Konishi  * Written by Koji Sato.
817c76b01SKoji Sato  */
917c76b01SKoji Sato 
1017c76b01SKoji Sato #ifndef _NILFS_BTREE_H
1117c76b01SKoji Sato #define _NILFS_BTREE_H
1217c76b01SKoji Sato 
1317c76b01SKoji Sato #include <linux/types.h>
1417c76b01SKoji Sato #include <linux/buffer_head.h>
1517c76b01SKoji Sato #include <linux/list.h>
16e63e88bcSRyusuke Konishi #include <linux/nilfs2_ondisk.h>	/* nilfs_btree_node */
1717c76b01SKoji Sato #include "btnode.h"
1817c76b01SKoji Sato #include "bmap.h"
1917c76b01SKoji Sato 
2017c76b01SKoji Sato /**
2141c88bd7SLi Hong  * struct nilfs_btree_path - A path on which B-tree operations are executed
2241c88bd7SLi Hong  * @bp_bh: buffer head of node block
2341c88bd7SLi Hong  * @bp_sib_bh: buffer head of sibling node block
2441c88bd7SLi Hong  * @bp_index: index of child node
2541c88bd7SLi Hong  * @bp_oldreq: ptr end request for old ptr
2641c88bd7SLi Hong  * @bp_newreq: ptr alloc request for new ptr
2741c88bd7SLi Hong  * @bp_op: rebalance operation
2841c88bd7SLi Hong  */
2941c88bd7SLi Hong struct nilfs_btree_path {
3041c88bd7SLi Hong 	struct buffer_head *bp_bh;
3141c88bd7SLi Hong 	struct buffer_head *bp_sib_bh;
3241c88bd7SLi Hong 	int bp_index;
3341c88bd7SLi Hong 	union nilfs_bmap_ptr_req bp_oldreq;
3441c88bd7SLi Hong 	union nilfs_bmap_ptr_req bp_newreq;
3541c88bd7SLi Hong 	struct nilfs_btnode_chkey_ctxt bp_ctxt;
36e7c274f8SRyusuke Konishi 	void (*bp_op)(struct nilfs_bmap *, struct nilfs_btree_path *,
3741c88bd7SLi Hong 		      int, __u64 *, __u64 *);
3841c88bd7SLi Hong };
3917c76b01SKoji Sato 
4017c76b01SKoji Sato #define NILFS_BTREE_ROOT_SIZE		NILFS_BMAP_SIZE
4117c76b01SKoji Sato #define NILFS_BTREE_ROOT_NCHILDREN_MAX					\
4217c76b01SKoji Sato 	((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) /	\
4317c76b01SKoji Sato 	 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
4417c76b01SKoji Sato #define NILFS_BTREE_ROOT_NCHILDREN_MIN	0
4517c76b01SKoji Sato #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE	(sizeof(__le64))
4617c76b01SKoji Sato #define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize)			\
4717c76b01SKoji Sato 	(((nodesize) - sizeof(struct nilfs_btree_node) -		\
4817c76b01SKoji Sato 		NILFS_BTREE_NODE_EXTRA_PAD_SIZE) /			\
4917c76b01SKoji Sato 	 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
5017c76b01SKoji Sato #define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize)			\
5117c76b01SKoji Sato 	((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1)
5217c76b01SKoji Sato #define NILFS_BTREE_KEY_MIN	((__u64)0)
5317c76b01SKoji Sato #define NILFS_BTREE_KEY_MAX	(~(__u64)0)
5417c76b01SKoji Sato 
5541c88bd7SLi Hong extern struct kmem_cache *nilfs_btree_path_cache;
5617c76b01SKoji Sato 
573033342aSRyusuke Konishi int nilfs_btree_init(struct nilfs_bmap *);
5817c76b01SKoji Sato int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
593033342aSRyusuke Konishi 				   const __u64 *, const __u64 *, int);
6017c76b01SKoji Sato void nilfs_btree_init_gc(struct nilfs_bmap *);
6117c76b01SKoji Sato 
621d5385b9SRyusuke Konishi int nilfs_btree_broken_node_block(struct buffer_head *bh);
631d5385b9SRyusuke Konishi 
6417c76b01SKoji Sato #endif	/* _NILFS_BTREE_H */
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