1 files changed, 76 insertions, 0 deletions
diff --git a/Kernel/VM/Range.h b/Kernel/VM/Range.h
new file mode 100644
index 0000000000..9d1c6ca476
--- /dev/null
+++ b/Kernel/VM/Range.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <Kernel/VirtualAddress.h>
+
+namespace Kernel {
+
+class Range {
+    friend class RangeAllocator;
+
+public:
+    Range() = delete;
+    Range(VirtualAddress base, size_t size)
+        : m_base(base)
+        , m_size(size)
+    {
+    }
+
+    VirtualAddress base() const { return m_base; }
+    size_t size() const { return m_size; }
+    bool is_valid() const { return !m_base.is_null(); }
+
+    bool contains(VirtualAddress vaddr) const { return vaddr >= base() && vaddr < end(); }
+
+    VirtualAddress end() const { return m_base.offset(m_size); }
+
+    bool operator==(const Range& other) const
+    {
+        return m_base == other.m_base && m_size == other.m_size;
+    }
+
+    bool contains(VirtualAddress base, size_t size) const
+    {
+        if (base.offset(size) < base)
+            return false;
+        return base >= m_base && base.offset(size) <= end();
+    }
+
+    bool contains(const Range& other) const
+    {
+        return contains(other.base(), other.size());
+    }
+
+    Vector<Range, 2> carve(const Range&) const;
+
+private:
+    VirtualAddress m_base;
+    size_t m_size { 0 };
+};
+
+}