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diff --git a/src/seastar/include/seastar/core/layered_file.hh b/src/seastar/include/seastar/core/layered_file.hh
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+/*
+ * This file is open source software, licensed to you under the terms
+ * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership.  You may not use this file except in compliance with the License.
+ *
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+/*
+ * Copyright 2020 ScyllaDB
+ */
+
+#pragma once
+
+#include <seastar/core/file.hh>
+
+namespace seastar {
+
+/// \addtogroup fileio-module
+/// @{
+
+/// Base class for layered file implementations.
+///
+/// A layered file implementation implements `file_impl` virtual
+/// functions such as dma_read() by forwarding them to another, existing
+/// file called the underlying file. This base class simplifies construction
+/// of layered files by performing standard tasks such as setting up the
+/// file alignment. Actual implementation of the I/O methods is left for the
+/// derived class.
+class layered_file_impl : public file_impl {
+protected:
+    file _underlying_file;
+public:
+    /// Constructs a layered file. This sets up the underlying_file() method
+    /// and initializes alignment constants to be the same as the underlying file.
+    explicit layered_file_impl(file underlying_file) noexcept
+            : _underlying_file(std::move(underlying_file)) {
+        _memory_dma_alignment = _underlying_file.memory_dma_alignment();
+        _disk_read_dma_alignment = _underlying_file.disk_read_dma_alignment();
+        _disk_write_dma_alignment = _underlying_file.disk_write_dma_alignment();
+    }
+
+    /// The underlying file which can be used to back I/O methods.
+    file& underlying_file() noexcept {
+        return _underlying_file;
+    }
+
+    /// The underlying file which can be used to back I/O methods.
+    const file& underlying_file() const noexcept {
+        return _underlying_file;
+    }
+};
+
+
+/// @}
+
+
+}