xref: /OK3568_Linux_fs/kernel/fs/nilfs2/btree.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0+ */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * btree.h - NILFS B-tree.
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * Written by Koji Sato.
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #ifndef _NILFS_BTREE_H
11*4882a593Smuzhiyun #define _NILFS_BTREE_H
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #include <linux/types.h>
14*4882a593Smuzhiyun #include <linux/buffer_head.h>
15*4882a593Smuzhiyun #include <linux/list.h>
16*4882a593Smuzhiyun #include <linux/nilfs2_ondisk.h>	/* nilfs_btree_node */
17*4882a593Smuzhiyun #include "btnode.h"
18*4882a593Smuzhiyun #include "bmap.h"
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun /**
21*4882a593Smuzhiyun  * struct nilfs_btree_path - A path on which B-tree operations are executed
22*4882a593Smuzhiyun  * @bp_bh: buffer head of node block
23*4882a593Smuzhiyun  * @bp_sib_bh: buffer head of sibling node block
24*4882a593Smuzhiyun  * @bp_index: index of child node
25*4882a593Smuzhiyun  * @bp_oldreq: ptr end request for old ptr
26*4882a593Smuzhiyun  * @bp_newreq: ptr alloc request for new ptr
27*4882a593Smuzhiyun  * @bp_op: rebalance operation
28*4882a593Smuzhiyun  */
29*4882a593Smuzhiyun struct nilfs_btree_path {
30*4882a593Smuzhiyun 	struct buffer_head *bp_bh;
31*4882a593Smuzhiyun 	struct buffer_head *bp_sib_bh;
32*4882a593Smuzhiyun 	int bp_index;
33*4882a593Smuzhiyun 	union nilfs_bmap_ptr_req bp_oldreq;
34*4882a593Smuzhiyun 	union nilfs_bmap_ptr_req bp_newreq;
35*4882a593Smuzhiyun 	struct nilfs_btnode_chkey_ctxt bp_ctxt;
36*4882a593Smuzhiyun 	void (*bp_op)(struct nilfs_bmap *, struct nilfs_btree_path *,
37*4882a593Smuzhiyun 		      int, __u64 *, __u64 *);
38*4882a593Smuzhiyun };
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun #define NILFS_BTREE_ROOT_SIZE		NILFS_BMAP_SIZE
41*4882a593Smuzhiyun #define NILFS_BTREE_ROOT_NCHILDREN_MAX					\
42*4882a593Smuzhiyun 	((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) /	\
43*4882a593Smuzhiyun 	 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
44*4882a593Smuzhiyun #define NILFS_BTREE_ROOT_NCHILDREN_MIN	0
45*4882a593Smuzhiyun #define NILFS_BTREE_NODE_EXTRA_PAD_SIZE	(sizeof(__le64))
46*4882a593Smuzhiyun #define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize)			\
47*4882a593Smuzhiyun 	(((nodesize) - sizeof(struct nilfs_btree_node) -		\
48*4882a593Smuzhiyun 		NILFS_BTREE_NODE_EXTRA_PAD_SIZE) /			\
49*4882a593Smuzhiyun 	 (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */)))
50*4882a593Smuzhiyun #define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize)			\
51*4882a593Smuzhiyun 	((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1)
52*4882a593Smuzhiyun #define NILFS_BTREE_KEY_MIN	((__u64)0)
53*4882a593Smuzhiyun #define NILFS_BTREE_KEY_MAX	(~(__u64)0)
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun extern struct kmem_cache *nilfs_btree_path_cache;
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun int nilfs_btree_init(struct nilfs_bmap *);
58*4882a593Smuzhiyun int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64,
59*4882a593Smuzhiyun 				   const __u64 *, const __u64 *, int);
60*4882a593Smuzhiyun void nilfs_btree_init_gc(struct nilfs_bmap *);
61*4882a593Smuzhiyun 
62*4882a593Smuzhiyun int nilfs_btree_broken_node_block(struct buffer_head *bh);
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun #endif	/* _NILFS_BTREE_H */
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