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/*
* QEMU aio implementation
*
* Copyright IBM, Corp. 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef QEMU_AIO_H
#define QEMU_AIO_H
#include "qemu-common.h"
#include "qemu-char.h"
/* Returns 1 if there are still outstanding AIO requests; 0 otherwise */
typedef int (AioFlushHandler)(void *opaque);
/* Flush any pending AIO operation. This function will block until all
* outstanding AIO operations have been completed or cancelled. */
void qemu_aio_flush(void);
/* Wait for a single AIO completion to occur. This function will until a
* single AIO opeartion has completed. It is intended to be used as a looping
* primative when simulating synchronous IO based on asynchronous IO. */
void qemu_aio_wait(void);
/* Register a file descriptor and associated callbacks. Behaves very similarly
* to qemu_set_fd_handler2. Unlike qemu_set_fd_handler2, these callbacks will
* be invoked when using either qemu_aio_wait() or qemu_aio_flush().
*
* Code that invokes AIO completion functions should rely on this function
* instead of qemu_set_fd_handler[2].
*/
int qemu_aio_set_fd_handler(int fd,
IOHandler *io_read,
IOHandler *io_write,
AioFlushHandler *io_flush,
void *opaque);
#endif
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