linux-zen-server/drivers/iommu/iommufd/double_span.h

54 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES.
*/
#ifndef __IOMMUFD_DOUBLE_SPAN_H
#define __IOMMUFD_DOUBLE_SPAN_H
#include <linux/interval_tree.h>
/*
* This is a variation of the general interval_tree_span_iter that computes the
* spans over the union of two different interval trees. Used ranges are broken
* up and reported based on the tree that provides the interval. The first span
* always takes priority. Like interval_tree_span_iter it is greedy and the same
* value of is_used will not repeat on two iteration cycles.
*/
struct interval_tree_double_span_iter {
struct rb_root_cached *itrees[2];
struct interval_tree_span_iter spans[2];
union {
unsigned long start_hole;
unsigned long start_used;
};
union {
unsigned long last_hole;
unsigned long last_used;
};
/* 0 = hole, 1 = used span[0], 2 = used span[1], -1 done iteration */
int is_used;
};
void interval_tree_double_span_iter_update(
struct interval_tree_double_span_iter *iter);
void interval_tree_double_span_iter_first(
struct interval_tree_double_span_iter *iter,
struct rb_root_cached *itree1, struct rb_root_cached *itree2,
unsigned long first_index, unsigned long last_index);
void interval_tree_double_span_iter_next(
struct interval_tree_double_span_iter *iter);
static inline bool
interval_tree_double_span_iter_done(struct interval_tree_double_span_iter *state)
{
return state->is_used == -1;
}
#define interval_tree_for_each_double_span(span, itree1, itree2, first_index, \
last_index) \
for (interval_tree_double_span_iter_first(span, itree1, itree2, \
first_index, last_index); \
!interval_tree_double_span_iter_done(span); \
interval_tree_double_span_iter_next(span))
#endif