v4.19.13 snapshot.
diff --git a/include/linux/range.h b/include/linux/range.h
new file mode 100644
index 0000000..d1fbeb6
--- /dev/null
+++ b/include/linux/range.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_RANGE_H
+#define _LINUX_RANGE_H
+
+struct range {
+	u64   start;
+	u64   end;
+};
+
+int add_range(struct range *range, int az, int nr_range,
+		u64 start, u64 end);
+
+
+int add_range_with_merge(struct range *range, int az, int nr_range,
+				u64 start, u64 end);
+
+void subtract_range(struct range *range, int az, u64 start, u64 end);
+
+int clean_sort_range(struct range *range, int az);
+
+void sort_range(struct range *range, int nr_range);
+
+#define MAX_RESOURCE ((resource_size_t)~0)
+static inline resource_size_t cap_resource(u64 val)
+{
+	if (val > MAX_RESOURCE)
+		return MAX_RESOURCE;
+
+	return val;
+}
+#endif