1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (C) 2020 Oracle.  All Rights Reserved.
4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
5  */
6 #ifndef __XFS_BTREE_STAGING_H__
7 #define __XFS_BTREE_STAGING_H__
8 
9 /* Fake root for an AG-rooted btree. */
10 struct xbtree_afakeroot {
11 	/* AG block number of the new btree root. */
12 	xfs_agblock_t		af_root;
13 
14 	/* Height of the new btree. */
15 	unsigned int		af_levels;
16 
17 	/* Number of blocks used by the btree. */
18 	unsigned int		af_blocks;
19 };
20 
21 /* Cursor interactions with fake roots for AG-rooted btrees. */
22 void xfs_btree_stage_afakeroot(struct xfs_btree_cur *cur,
23 		struct xbtree_afakeroot *afake);
24 void xfs_btree_commit_afakeroot(struct xfs_btree_cur *cur, struct xfs_trans *tp,
25 		struct xfs_buf *agbp, const struct xfs_btree_ops *ops);
26 
27 /* Fake root for an inode-rooted btree. */
28 struct xbtree_ifakeroot {
29 	/* Fake inode fork. */
30 	struct xfs_ifork	*if_fork;
31 
32 	/* Number of blocks used by the btree. */
33 	int64_t			if_blocks;
34 
35 	/* Height of the new btree. */
36 	unsigned int		if_levels;
37 
38 	/* Number of bytes available for this fork in the inode. */
39 	unsigned int		if_fork_size;
40 };
41 
42 /* Cursor interactions with fake roots for inode-rooted btrees. */
43 void xfs_btree_stage_ifakeroot(struct xfs_btree_cur *cur,
44 		struct xbtree_ifakeroot *ifake,
45 		struct xfs_btree_ops **new_ops);
46 void xfs_btree_commit_ifakeroot(struct xfs_btree_cur *cur, struct xfs_trans *tp,
47 		int whichfork, const struct xfs_btree_ops *ops);
48 
49 /* Bulk loading of staged btrees. */
50 typedef int (*xfs_btree_bload_get_record_fn)(struct xfs_btree_cur *cur, void *priv);
51 typedef int (*xfs_btree_bload_claim_block_fn)(struct xfs_btree_cur *cur,
52 		union xfs_btree_ptr *ptr, void *priv);
53 typedef size_t (*xfs_btree_bload_iroot_size_fn)(struct xfs_btree_cur *cur,
54 		unsigned int nr_this_level, void *priv);
55 
56 struct xfs_btree_bload {
57 	/*
58 	 * This function will be called nr_records times to load records into
59 	 * the btree.  The function does this by setting the cursor's bc_rec
60 	 * field in in-core format.  Records must be returned in sort order.
61 	 */
62 	xfs_btree_bload_get_record_fn	get_record;
63 
64 	/*
65 	 * This function will be called nr_blocks times to obtain a pointer
66 	 * to a new btree block on disk.  Callers must preallocate all space
67 	 * for the new btree before calling xfs_btree_bload, and this function
68 	 * is what claims that reservation.
69 	 */
70 	xfs_btree_bload_claim_block_fn	claim_block;
71 
72 	/*
73 	 * This function should return the size of the in-core btree root
74 	 * block.  It is only necessary for XFS_BTREE_ROOT_IN_INODE btree
75 	 * types.
76 	 */
77 	xfs_btree_bload_iroot_size_fn	iroot_size;
78 
79 	/*
80 	 * The caller should set this to the number of records that will be
81 	 * stored in the new btree.
82 	 */
83 	uint64_t			nr_records;
84 
85 	/*
86 	 * Number of free records to leave in each leaf block.  If the caller
87 	 * sets this to -1, the slack value will be calculated to be halfway
88 	 * between maxrecs and minrecs.  This typically leaves the block 75%
89 	 * full.  Note that slack values are not enforced on inode root blocks.
90 	 */
91 	int				leaf_slack;
92 
93 	/*
94 	 * Number of free key/ptrs pairs to leave in each node block.  This
95 	 * field has the same semantics as leaf_slack.
96 	 */
97 	int				node_slack;
98 
99 	/*
100 	 * The xfs_btree_bload_compute_geometry function will set this to the
101 	 * number of btree blocks needed to store nr_records records.
102 	 */
103 	uint64_t			nr_blocks;
104 
105 	/*
106 	 * The xfs_btree_bload_compute_geometry function will set this to the
107 	 * height of the new btree.
108 	 */
109 	unsigned int			btree_height;
110 };
111 
112 int xfs_btree_bload_compute_geometry(struct xfs_btree_cur *cur,
113 		struct xfs_btree_bload *bbl, uint64_t nr_records);
114 int xfs_btree_bload(struct xfs_btree_cur *cur, struct xfs_btree_bload *bbl,
115 		void *priv);
116 
117 #endif	/* __XFS_BTREE_STAGING_H__ */
118