1/* include/linux/aio_abi.h
2 *
3 * Copyright 2000,2001,2002 Red Hat.
4 *
5 * Written by Benjamin LaHaise <bcrl@kvack.org>
6 *
7 * Distribute under the terms of the GPLv2 (see ../../COPYING) or under
8 * the following terms.
9 *
10 * Permission to use, copy, modify, and distribute this software and its
11 * documentation is hereby granted, provided that the above copyright
12 * notice appears in all copies. This software is provided without any
13 * warranty, express or implied. Red Hat makes no representations about
14 * the suitability of this software for any purpose.
15 *
16 * IN NO EVENT SHALL RED HAT BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
17 * SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF
18 * THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF RED HAT HAS BEEN ADVISED
19 * OF THE POSSIBILITY OF SUCH DAMAGE.
20 *
21 * RED HAT DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND
24 * RED HAT HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
25 * ENHANCEMENTS, OR MODIFICATIONS.
26 */
27#ifndef __LINUX__AIO_ABI_H
28#define __LINUX__AIO_ABI_H
29
30#include <linux/types.h>
31#include <linux/fs.h>
32#include <asm/byteorder.h>
33
34typedef __kernel_ulong_t aio_context_t;
35
36enum {
37 IOCB_CMD_PREAD = 0,
38 IOCB_CMD_PWRITE = 1,
39 IOCB_CMD_FSYNC = 2,
40 IOCB_CMD_FDSYNC = 3,
41 /* 4 was the experimental IOCB_CMD_PREADX */
42 IOCB_CMD_POLL = 5,
43 IOCB_CMD_NOOP = 6,
44 IOCB_CMD_PREADV = 7,
45 IOCB_CMD_PWRITEV = 8,
46};
47
48/*
49 * Valid flags for the "aio_flags" member of the "struct iocb".
50 *
51 * IOCB_FLAG_RESFD - Set if the "aio_resfd" member of the "struct iocb"
52 * is valid.
53 * IOCB_FLAG_IOPRIO - Set if the "aio_reqprio" member of the "struct iocb"
54 * is valid.
55 */
56#define IOCB_FLAG_RESFD (1 << 0)
57#define IOCB_FLAG_IOPRIO (1 << 1)
58
59/* read() from /dev/aio returns these structures. */
60struct io_event {
61 __u64 data; /* the data field from the iocb */
62 __u64 obj; /* what iocb this event came from */
63 __s64 res; /* result code for this event */
64 __s64 res2; /* secondary result */
65};
66
67/*
68 * we always use a 64bit off_t when communicating
69 * with userland. its up to libraries to do the
70 * proper padding and aio_error abstraction
71 */
72
73struct iocb {
74 /* these are internal to the kernel/libc. */
75 __u64 aio_data; /* data to be returned in event's data */
76
77#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN)
78 __u32 aio_key; /* the kernel sets aio_key to the req # */
79 __kernel_rwf_t aio_rw_flags; /* RWF_* flags */
80#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : defined(__BIG_ENDIAN)
81 __kernel_rwf_t aio_rw_flags; /* RWF_* flags */
82 __u32 aio_key; /* the kernel sets aio_key to the req # */
83#else
84#error edit for your odd byteorder.
85#endif
86
87 /* common fields */
88 __u16 aio_lio_opcode; /* see IOCB_CMD_ above */
89 __s16 aio_reqprio;
90 __u32 aio_fildes;
91
92 __u64 aio_buf;
93 __u64 aio_nbytes;
94 __s64 aio_offset;
95
96 /* extra parameters */
97 __u64 aio_reserved2; /* TODO: use this for a (struct sigevent *) */
98
99 /* flags for the "struct iocb" */
100 __u32 aio_flags;
101
102 /*
103 * if the IOCB_FLAG_RESFD flag of "aio_flags" is set, this is an
104 * eventfd to signal AIO readiness to
105 */
106 __u32 aio_resfd;
107}; /* 64 bytes */
108
109#undef IFBIG
110#undef IFLITTLE
111
112#endif /* __LINUX__AIO_ABI_H */
113
114