qemu-e2k/include/qemu/interval-tree.h

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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Interval trees.
*
* Derived from include/linux/interval_tree.h and its dependencies.
*/
#ifndef QEMU_INTERVAL_TREE_H
#define QEMU_INTERVAL_TREE_H
/*
* For now, don't expose Linux Red-Black Trees separately, but retain the
* separate type definitions to keep the implementation sane, and allow
* the possibility of disentangling them later.
*/
typedef struct RBNode
{
/* Encodes parent with color in the lsb. */
uintptr_t rb_parent_color;
struct RBNode *rb_right;
struct RBNode *rb_left;
} RBNode;
typedef struct RBRoot
{
RBNode *rb_node;
} RBRoot;
typedef struct RBRootLeftCached {
RBRoot rb_root;
RBNode *rb_leftmost;
} RBRootLeftCached;
typedef struct IntervalTreeNode
{
RBNode rb;
uint64_t start; /* Start of interval */
uint64_t last; /* Last location _in_ interval */
uint64_t subtree_last;
} IntervalTreeNode;
typedef RBRootLeftCached IntervalTreeRoot;
/**
* interval_tree_is_empty
* @root: root of the tree.
*
* Returns true if the tree contains no nodes.
*/
static inline bool interval_tree_is_empty(const IntervalTreeRoot *root)
{
return root->rb_root.rb_node == NULL;
}
/**
* interval_tree_insert
* @node: node to insert,
* @root: root of the tree.
*
* Insert @node into @root, and rebalance.
*/
void interval_tree_insert(IntervalTreeNode *node, IntervalTreeRoot *root);
/**
* interval_tree_remove
* @node: node to remove,
* @root: root of the tree.
*
* Remove @node from @root, and rebalance.
*/
void interval_tree_remove(IntervalTreeNode *node, IntervalTreeRoot *root);
/**
* interval_tree_iter_first:
* @root: root of the tree,
* @start, @last: the inclusive interval [start, last].
*
* Locate the "first" of a set of nodes within the tree at @root
* that overlap the interval, where "first" is sorted by start.
* Returns NULL if no overlap found.
*/
IntervalTreeNode *interval_tree_iter_first(IntervalTreeRoot *root,
uint64_t start, uint64_t last);
/**
* interval_tree_iter_next:
* @node: previous search result
* @start, @last: the inclusive interval [start, last].
*
* Locate the "next" of a set of nodes within the tree that overlap the
* interval; @next is the result of a previous call to
* interval_tree_iter_{first,next}. Returns NULL if @next was the last
* node in the set.
*/
IntervalTreeNode *interval_tree_iter_next(IntervalTreeNode *node,
uint64_t start, uint64_t last);
#endif /* QEMU_INTERVAL_TREE_H */