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diff --git a/mtp/ffs/AsyncIO.h b/mtp/ffs/AsyncIO.h
new file mode 100644
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+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * 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.
+ */
+
+#ifndef _ASYNCIO_H
+#define _ASYNCIO_H
+
+#include <fcntl.h>
+#include <linux/aio_abi.h>
+#include <memory>
+#include <signal.h>
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <time.h>
+#include <thread>
+#include <unistd.h>
+
+/**
+ * Provides a subset of POSIX aio operations, as well
+ * as similar operations with splice and threadpools.
+ */
+
+struct aiocb {
+	int aio_fildes;		// Assumed to be the source for splices
+	void *aio_buf;		// Unused for splices
+
+	// Used for threadpool operations only, freed automatically
+	std::unique_ptr<char[]> aio_pool_buf;
+
+	off_t aio_offset;
+	size_t aio_nbytes;
+
+	int aio_sink;		// Unused for non splice r/w
+
+	// Used internally
+	std::thread thread;
+	ssize_t ret;
+	int error;
+
+	~aiocb();
+};
+
+// Submit a request for IO to be completed
+int aio_read(struct aiocb *);
+int aio_write(struct aiocb *);
+int aio_splice_read(struct aiocb *);
+int aio_splice_write(struct aiocb *);
+
+// Suspend current thread until given IO is complete, at which point
+// its return value and any errors can be accessed
+// All submitted requests must have a corresponding suspend.
+// aiocb->aio_buf must refer to valid memory until after the suspend call
+int aio_suspend(struct aiocb *[], int, const struct timespec *);
+int aio_error(const struct aiocb *);
+ssize_t aio_return(struct aiocb *);
+
+// (Currently unimplemented)
+int aio_cancel(int, struct aiocb *);
+
+// Initialize a threadpool to perform IO. Only one pool can be
+// running at a time.
+void aio_pool_write_init();
+void aio_pool_splice_init();
+// Suspend current thread until all queued work is complete, then ends the threadpool
+void aio_pool_end();
+// Submit IO work for the threadpool to complete. Memory associated with the work is
+// freed automatically when the work is complete.
+int aio_pool_write(struct aiocb *);
+
+#endif // ASYNCIO_H
+