qemu/block/raw-aio.h
Paolo Bonzini 8238010b26 block: make discard asynchronous
This is easy with the thread pool, because we can use s->is_xfs and
s->has_discard from the worker function.

QEMU has a widespread assumption that each I/O operation writes less
than 2^32 bytes.  This patch doesn't fix it throughout of course,
but it starts correcting struct RawPosixAIOData so that there is
no regression with respect to the synchronous discard implementation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-01-15 10:03:47 +01:00

52 lines
1.6 KiB
C

/*
* Declarations for AIO in the raw protocol
*
* 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.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#ifndef QEMU_RAW_AIO_H
#define QEMU_RAW_AIO_H
/* AIO request types */
#define QEMU_AIO_READ 0x0001
#define QEMU_AIO_WRITE 0x0002
#define QEMU_AIO_IOCTL 0x0004
#define QEMU_AIO_FLUSH 0x0008
#define QEMU_AIO_DISCARD 0x0010
#define QEMU_AIO_TYPE_MASK \
(QEMU_AIO_READ|QEMU_AIO_WRITE|QEMU_AIO_IOCTL|QEMU_AIO_FLUSH| \
QEMU_AIO_DISCARD)
/* AIO flags */
#define QEMU_AIO_MISALIGNED 0x1000
#define QEMU_AIO_BLKDEV 0x2000
/* linux-aio.c - Linux native implementation */
#ifdef CONFIG_LINUX_AIO
void *laio_init(void);
BlockDriverAIOCB *laio_submit(BlockDriverState *bs, void *aio_ctx, int fd,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque, int type);
#endif
#ifdef _WIN32
typedef struct QEMUWin32AIOState QEMUWin32AIOState;
QEMUWin32AIOState *win32_aio_init(void);
int win32_aio_attach(QEMUWin32AIOState *aio, HANDLE hfile);
BlockDriverAIOCB *win32_aio_submit(BlockDriverState *bs,
QEMUWin32AIOState *aio, HANDLE hfile,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque, int type);
#endif
#endif /* QEMU_RAW_AIO_H */