Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/drivers/iommu/iommufd/double_span.h b/drivers/iommu/iommufd/double_span.h
new file mode 100644
index 0000000000..b37aab7488
--- /dev/null
+++ b/drivers/iommu/iommufd/double_span.h
@@ -0,0 +1,53 @@
+/* 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