1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/xe_range_fence.c b/drivers/gpu/drm/xe/xe_range_fence.c
new file mode 100644
index 000000000000..d35d9ec58e86
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_range_fence.c
@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#include <linux/dma-fence.h>
+#include <linux/interval_tree_generic.h>
+#include <linux/slab.h>
+
+#include "xe_macros.h"
+#include "xe_range_fence.h"
+
+#define XE_RANGE_TREE_START(_node)	((_node)->start)
+#define XE_RANGE_TREE_LAST(_node)	((_node)->last)
+
+INTERVAL_TREE_DEFINE(struct xe_range_fence, rb, u64, __subtree_last,
+		     XE_RANGE_TREE_START, XE_RANGE_TREE_LAST, static,
+		     xe_range_fence_tree);
+
+static void
+xe_range_fence_signal_notify(struct dma_fence *fence, struct dma_fence_cb *cb)
+{
+	struct xe_range_fence *rfence = container_of(cb, typeof(*rfence), cb);
+	struct xe_range_fence_tree *tree = rfence->tree;
+
+	llist_add(&rfence->link, &tree->list);
+}
+
+static bool __xe_range_fence_tree_cleanup(struct xe_range_fence_tree *tree)
+{
+	struct llist_node *node = llist_del_all(&tree->list);
+	struct xe_range_fence *rfence, *next;
+
+	llist_for_each_entry_safe(rfence, next, node, link) {
+		xe_range_fence_tree_remove(rfence, &tree->root);
+		dma_fence_put(rfence->fence);
+		kfree(rfence);
+	}
+
+	return !!node;
+}
+
+/**
+ * xe_range_fence_insert() - range fence insert
+ * @tree: range fence tree to insert intoi
+ * @rfence: range fence
+ * @ops: range fence ops
+ * @start: start address of range fence
+ * @last: last address of range fence
+ * @fence: dma fence which signals range fence can be removed + freed
+ *
+ * Return: 0 on success, non-zero on failure
+ */
+int xe_range_fence_insert(struct xe_range_fence_tree *tree,
+			  struct xe_range_fence *rfence,
+			  const struct xe_range_fence_ops *ops,
+			  u64 start, u64 last, struct dma_fence *fence)
+{
+	int err = 0;
+
+	__xe_range_fence_tree_cleanup(tree);
+
+	if (dma_fence_is_signaled(fence))
+		goto free;
+
+	rfence->ops = ops;
+	rfence->start = start;
+	rfence->last = last;
+	rfence->tree = tree;
+	rfence->fence = dma_fence_get(fence);
+	err = dma_fence_add_callback(fence, &rfence->cb,
+				     xe_range_fence_signal_notify);
+	if (err == -ENOENT) {
+		dma_fence_put(fence);
+		err = 0;
+		goto free;
+	} else if (err == 0) {
+		xe_range_fence_tree_insert(rfence, &tree->root);
+		return 0;
+	}
+
+free:
+	if (ops->free)
+		ops->free(rfence);
+
+	return err;
+}
+
+static void xe_range_fence_tree_remove_all(struct xe_range_fence_tree *tree)
+{
+	struct xe_range_fence *rfence;
+	bool retry = true;
+
+	rfence = xe_range_fence_tree_iter_first(&tree->root, 0, U64_MAX);
+	while (rfence) {
+		/* Should be ok with the minimalistic callback */
+		if (dma_fence_remove_callback(rfence->fence, &rfence->cb))
+			llist_add(&rfence->link, &tree->list);
+		rfence = xe_range_fence_tree_iter_next(rfence, 0, U64_MAX);
+	}
+
+	while (retry)
+		retry = __xe_range_fence_tree_cleanup(tree);
+}
+
+/**
+ * xe_range_fence_tree_init() - Init range fence tree
+ * @tree: range fence tree
+ */
+void xe_range_fence_tree_init(struct xe_range_fence_tree *tree)
+{
+	memset(tree, 0, sizeof(*tree));
+}
+
+/**
+ * xe_range_fence_tree_fini() - Fini range fence tree
+ * @tree: range fence tree
+ */
+void xe_range_fence_tree_fini(struct xe_range_fence_tree *tree)
+{
+	xe_range_fence_tree_remove_all(tree);
+	XE_WARN_ON(!RB_EMPTY_ROOT(&tree->root.rb_root));
+}
+
+/**
+ * xe_range_fence_tree_first() - range fence tree iterator first
+ * @tree: range fence tree
+ * @start: start address of range fence
+ * @last: last address of range fence
+ *
+ * Return: first range fence found in range or NULL
+ */
+struct xe_range_fence *
+xe_range_fence_tree_first(struct xe_range_fence_tree *tree, u64 start,
+			  u64 last)
+{
+	return xe_range_fence_tree_iter_first(&tree->root, start, last);
+}
+
+/**
+ * xe_range_fence_tree_next() - range fence tree iterator next
+ * @rfence: current range fence
+ * @start: start address of range fence
+ * @last: last address of range fence
+ *
+ * Return: next range fence found in range or NULL
+ */
+struct xe_range_fence *
+xe_range_fence_tree_next(struct xe_range_fence *rfence, u64 start, u64 last)
+{
+	return xe_range_fence_tree_iter_next(rfence, start, last);
+}
+
+const struct xe_range_fence_ops xe_range_fence_kfree_ops = {
+	.free = (void (*)(struct xe_range_fence *rfence)) kfree,
+};