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diff --git a/src/common/async/librados_completion.h b/src/common/async/librados_completion.h
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+++ b/src/common/async/librados_completion.h
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+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2020 Red Hat
+ * Author: Adam C. Emerson <aemerson@redhat.com>
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation. See file COPYING.
+ *
+ */
+
+#ifndef CEPH_COMMON_ASYNC_LIBRADOS_COMPLETION_H
+#define CEPH_COMMON_ASYNC_LIBRADOS_COMPLETION_H
+
+#include <atomic>
+#include <condition_variable>
+#include <mutex>
+#include <optional>
+#include <type_traits>
+
+#include <boost/asio/async_result.hpp>
+
+#include <boost/system/error_code.hpp>
+#include <boost/system/system_error.hpp>
+
+#include "include/rados/librados.hpp"
+#include "librados/AioCompletionImpl.h"
+
+// Allow librados::AioCompletion to be provided as a completion
+// handler. This is only allowed with a signature of
+// (boost::system::error_code) or (). On completion the AioCompletion
+// is completed with the error_code converted to an int with
+// ceph::from_error_code.
+//
+// async_result::return_type is void.
+
+namespace ceph::async {
+
+namespace bs = boost::system;
+namespace lr = librados;
+
+namespace detail {
+
+struct librados_handler {
+  lr::AioCompletionImpl* pc;
+
+  explicit librados_handler(lr::AioCompletion* c) : pc(c->pc) {
+    pc->get();
+  }
+  ~librados_handler() {
+    if (pc) {
+      pc->put();
+      pc = nullptr;
+    }
+  }
+
+  librados_handler(const librados_handler&) = delete;
+  librados_handler& operator =(const librados_handler&) = delete;
+  librados_handler(librados_handler&& rhs) {
+    pc = rhs.pc;
+    rhs.pc = nullptr;
+  }
+
+  void operator()(bs::error_code ec) {
+    pc->lock.lock();
+    pc->rval = ceph::from_error_code(ec);
+    pc->complete = true;
+    pc->lock.unlock();
+
+    auto cb_complete = pc->callback_complete;
+    auto cb_complete_arg = pc->callback_complete_arg;
+    if (cb_complete)
+      cb_complete(pc, cb_complete_arg);
+
+    auto cb_safe = pc->callback_safe;
+    auto cb_safe_arg = pc->callback_safe_arg;
+    if (cb_safe)
+      cb_safe(pc, cb_safe_arg);
+
+    pc->lock.lock();
+    pc->callback_complete = NULL;
+    pc->callback_safe = NULL;
+    pc->cond.notify_all();
+    pc->put_unlock();
+    pc = nullptr;
+  }
+
+  void operator ()() {
+    (*this)(bs::error_code{});
+  }
+};
+} // namespace detail
+} // namespace ceph::async
+
+
+namespace boost::asio {
+template<typename ReturnType>
+class async_result<librados::AioCompletion*, ReturnType()> {
+public:
+  using completion_handler_type = ceph::async::detail::librados_handler;
+  explicit async_result(completion_handler_type&) {};
+  using return_type = void;
+  void get() {
+    return;
+  }
+};
+
+template<typename ReturnType>
+class async_result<librados::AioCompletion*,
+		   ReturnType(boost::system::error_code)> {
+public:
+  using completion_handler_type = ceph::async::detail::librados_handler;
+  explicit async_result(completion_handler_type&) {};
+  using return_type = void;
+  void get() {
+    return;
+  }
+};
+}
+
+#endif // !CEPH_COMMON_ASYNC_LIBRADOS_COMPLETION_H