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