qcow2: Bring synchronous read/write back to life
[qemu-kvm/fedora.git] / posix-aio-compat.h
blob1c5dcbd92046e0c59cde4236f5a0d6395cceff67
1 /*
2 * QEMU posix-aio emulation
4 * Copyright IBM, Corp. 2008
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
14 #ifndef QEMU_POSIX_AIO_COMPAT_H
15 #define QEMU_POSIX_AIO_COMPAT_H
17 #include <sys/types.h>
18 #include <unistd.h>
19 #include <signal.h>
21 #include "sys-queue.h"
23 #define QEMU_PAIO_CANCELED 0x01
24 #define QEMU_PAIO_NOTCANCELED 0x02
25 #define QEMU_PAIO_ALLDONE 0x03
27 struct qemu_paiocb
29 int aio_fildes;
30 union {
31 struct iovec *aio_iov;
32 void *aio_ioctl_buf;
34 int aio_niov;
35 size_t aio_nbytes;
36 #define aio_ioctl_cmd aio_nbytes /* for QEMU_PAIO_IOCTL */
37 int ev_signo;
38 off_t aio_offset;
39 unsigned aio_flags;
40 /* 512 byte alignment required for buffer, offset and length */
41 #define QEMU_AIO_SECTOR_ALIGNED 0x01
43 /* private */
44 TAILQ_ENTRY(qemu_paiocb) node;
45 int aio_type;
46 #define QEMU_PAIO_READ 0x01
47 #define QEMU_PAIO_WRITE 0x02
48 #define QEMU_PAIO_IOCTL 0x03
49 ssize_t ret;
50 int active;
53 struct qemu_paioinit
55 unsigned int aio_threads;
56 unsigned int aio_num;
57 unsigned int aio_idle_time;
60 int qemu_paio_init(struct qemu_paioinit *aioinit);
61 int qemu_paio_read(struct qemu_paiocb *aiocb);
62 int qemu_paio_write(struct qemu_paiocb *aiocb);
63 int qemu_paio_ioctl(struct qemu_paiocb *aiocb);
64 int qemu_paio_error(struct qemu_paiocb *aiocb);
65 ssize_t qemu_paio_return(struct qemu_paiocb *aiocb);
66 int qemu_paio_cancel(int fd, struct qemu_paiocb *aiocb);
68 #endif