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. */
10struct 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. */
22void xfs_btree_stage_afakeroot(struct xfs_btree_cur *cur,
23		struct xbtree_afakeroot *afake);
24void xfs_btree_commit_afakeroot(struct xfs_btree_cur *cur, struct xfs_trans *tp,
25		struct xfs_buf *agbp);
26
27/* Fake root for an inode-rooted btree. */
28struct 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. */
43void xfs_btree_stage_ifakeroot(struct xfs_btree_cur *cur,
44		struct xbtree_ifakeroot *ifake);
45void xfs_btree_commit_ifakeroot(struct xfs_btree_cur *cur, struct xfs_trans *tp,
46		int whichfork);
47
48/* Bulk loading of staged btrees. */
49typedef int (*xfs_btree_bload_get_records_fn)(struct xfs_btree_cur *cur,
50		unsigned int idx, struct xfs_btree_block *block,
51		unsigned int nr_wanted, void *priv);
52typedef int (*xfs_btree_bload_claim_block_fn)(struct xfs_btree_cur *cur,
53		union xfs_btree_ptr *ptr, void *priv);
54typedef size_t (*xfs_btree_bload_iroot_size_fn)(struct xfs_btree_cur *cur,
55		unsigned int level, unsigned int nr_this_level, void *priv);
56
57struct xfs_btree_bload {
58	/*
59	 * This function will be called to load @nr_wanted records into the
60	 * btree.  The implementation does this by setting the cursor's bc_rec
61	 * field in in-core format and using init_rec_from_cur to set the
62	 * records in the btree block.  Records must be returned in sort order.
63	 * The function must return the number of records loaded or the usual
64	 * negative errno.
65	 */
66	xfs_btree_bload_get_records_fn	get_records;
67
68	/*
69	 * This function will be called nr_blocks times to obtain a pointer
70	 * to a new btree block on disk.  Callers must preallocate all space
71	 * for the new btree before calling xfs_btree_bload, and this function
72	 * is what claims that reservation.
73	 */
74	xfs_btree_bload_claim_block_fn	claim_block;
75
76	/*
77	 * This function should return the size of the in-core btree root
78	 * block.  It is only necessary for XFS_BTREE_TYPE_INODE btrees.
79	 */
80	xfs_btree_bload_iroot_size_fn	iroot_size;
81
82	/*
83	 * The caller should set this to the number of records that will be
84	 * stored in the new btree.
85	 */
86	uint64_t			nr_records;
87
88	/*
89	 * Number of free records to leave in each leaf block.  If the caller
90	 * sets this to -1, the slack value will be calculated to be halfway
91	 * between maxrecs and minrecs.  This typically leaves the block 75%
92	 * full.  Note that slack values are not enforced on inode root blocks.
93	 */
94	int				leaf_slack;
95
96	/*
97	 * Number of free key/ptrs pairs to leave in each node block.  This
98	 * field has the same semantics as leaf_slack.
99	 */
100	int				node_slack;
101
102	/*
103	 * The xfs_btree_bload_compute_geometry function will set this to the
104	 * number of btree blocks needed to store nr_records records.
105	 */
106	uint64_t			nr_blocks;
107
108	/*
109	 * The xfs_btree_bload_compute_geometry function will set this to the
110	 * height of the new btree.
111	 */
112	unsigned int			btree_height;
113
114	/*
115	 * Flush the new btree block buffer list to disk after this many blocks
116	 * have been formatted.  Zero prohibits writing any buffers until all
117	 * blocks have been formatted.
118	 */
119	uint16_t			max_dirty;
120
121	/* Number of dirty buffers. */
122	uint16_t			nr_dirty;
123};
124
125int xfs_btree_bload_compute_geometry(struct xfs_btree_cur *cur,
126		struct xfs_btree_bload *bbl, uint64_t nr_records);
127int xfs_btree_bload(struct xfs_btree_cur *cur, struct xfs_btree_bload *bbl,
128		void *priv);
129
130#endif	/* __XFS_BTREE_STAGING_H__ */
131