LXR linux/include/uapi/linux/aio

   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