LXR linux/fs/xfs/libxfs/xfs_btree

   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, const struct xfs_btree_ops *ops);
  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        /* Fork format. */
  42        unsigned int            if_format;
  43
  44        /* Number of records. */
  45        unsigned int            if_extents;
  46};
  47
  48/* Cursor interactions with fake roots for inode-rooted btrees. */
  49void xfs_btree_stage_ifakeroot(struct xfs_btree_cur *cur,
  50                struct xbtree_ifakeroot *ifake,
  51                struct xfs_btree_ops **new_ops);
  52void xfs_btree_commit_ifakeroot(struct xfs_btree_cur *cur, struct xfs_trans *tp,
  53                int whichfork, const struct xfs_btree_ops *ops);
  54
  55/* Bulk loading of staged btrees. */
  56typedef int (*xfs_btree_bload_get_record_fn)(struct xfs_btree_cur *cur, void *priv);
  57typedef int (*xfs_btree_bload_claim_block_fn)(struct xfs_btree_cur *cur,
  58                union xfs_btree_ptr *ptr, void *priv);
  59typedef size_t (*xfs_btree_bload_iroot_size_fn)(struct xfs_btree_cur *cur,
  60                unsigned int nr_this_level, void *priv);
  61
  62struct xfs_btree_bload {
  63        /*
  64         * This function will be called nr_records times to load records into
  65         * the btree.  The function does this by setting the cursor's bc_rec
  66         * field in in-core format.  Records must be returned in sort order.
  67         */
  68        xfs_btree_bload_get_record_fn   get_record;
  69
  70        /*
  71         * This function will be called nr_blocks times to obtain a pointer
  72         * to a new btree block on disk.  Callers must preallocate all space
  73         * for the new btree before calling xfs_btree_bload, and this function
  74         * is what claims that reservation.
  75         */
  76        xfs_btree_bload_claim_block_fn  claim_block;
  77
  78        /*
  79         * This function should return the size of the in-core btree root
  80         * block.  It is only necessary for XFS_BTREE_ROOT_IN_INODE btree
  81         * types.
  82         */
  83        xfs_btree_bload_iroot_size_fn   iroot_size;
  84
  85        /*
  86         * The caller should set this to the number of records that will be
  87         * stored in the new btree.
  88         */
  89        uint64_t                        nr_records;
  90
  91        /*
  92         * Number of free records to leave in each leaf block.  If the caller
  93         * sets this to -1, the slack value will be calculated to be halfway
  94         * between maxrecs and minrecs.  This typically leaves the block 75%
  95         * full.  Note that slack values are not enforced on inode root blocks.
  96         */
  97        int                             leaf_slack;
  98
  99        /*
 100         * Number of free key/ptrs pairs to leave in each node block.  This
 101         * field has the same semantics as leaf_slack.
 102         */
 103        int                             node_slack;
 104
 105        /*
 106         * The xfs_btree_bload_compute_geometry function will set this to the
 107         * number of btree blocks needed to store nr_records records.
 108         */
 109        uint64_t                        nr_blocks;
 110
 111        /*
 112         * The xfs_btree_bload_compute_geometry function will set this to the
 113         * height of the new btree.
 114         */
 115        unsigned int                    btree_height;
 116};
 117
 118int xfs_btree_bload_compute_geometry(struct xfs_btree_cur *cur,
 119                struct xfs_btree_bload *bbl, uint64_t nr_records);
 120int xfs_btree_bload(struct xfs_btree_cur *cur, struct xfs_btree_bload *bbl,
 121                void *priv);
 122
 123#endif  /* __XFS_BTREE_STAGING_H__ */
 124