aio.c revision 156136
1/* 2 * Copyright (c) 2005 David Xu <davidxu@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD: head/lib/librt/aio.c 156136 2006-03-01 06:37:34Z davidxu $ 27 * 28 */ 29 30#include <sys/cdefs.h> 31#include <sys/types.h> 32#include <sys/syscall.h> 33#include <sys/aio.h> 34 35#include "namespace.h" 36#include <errno.h> 37#include <pthread.h> 38#include <stddef.h> 39#include <signal.h> 40#include <unistd.h> 41#include "sigev_thread.h" 42#include "un-namespace.h" 43 44__weak_reference(__aio_read, _aio_read); 45__weak_reference(__aio_read, aio_read); 46__weak_reference(__aio_write, _aio_write); 47__weak_reference(__aio_write, aio_write); 48__weak_reference(__aio_return, _aio_return); 49__weak_reference(__aio_return, aio_return); 50__weak_reference(__aio_waitcomplete, _aio_waitcomplete); 51__weak_reference(__aio_waitcomplete, aio_waitcomplete); 52 53typedef void (*aio_func)(union sigval val, struct aiocb *iocb); 54 55extern int __sys_aio_read(struct aiocb *iocb); 56extern int __sys_aio_write(struct aiocb *iocb); 57extern int __sys_aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout); 58extern int __sys_aio_return(struct aiocb *iocb); 59extern int __sys_aio_error(struct aiocb *iocb); 60 61static void 62aio_dispatch(struct sigev_node *sn, siginfo_t *si) 63{ 64 aio_func f = sn->sn_func; 65 66 f(sn->sn_value, (struct aiocb *)sn->sn_id); 67} 68 69static int 70aio_io(struct aiocb *iocb, int (*sysfunc)(struct aiocb *iocb)) 71{ 72 struct sigev_node *sn; 73 struct sigevent saved_ev; 74 int ret; 75 76 if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD) { 77 ret = sysfunc(iocb); 78 return (ret); 79 } 80 81 if (__sigev_check_init()) { 82 /* This might be that thread library is not enabled. */ 83 errno = EINVAL; 84 return (-1); 85 } 86 87 sn = __sigev_alloc(SI_ASYNCIO, &iocb->aio_sigevent); 88 if (sn == NULL) { 89 errno = EAGAIN; 90 return (-1); 91 } 92 93 saved_ev = iocb->aio_sigevent; 94 sn->sn_id = (sigev_id_t)iocb; 95 sn->sn_flags |= SNF_ONESHOT; 96 __sigev_get_sigevent(sn, &iocb->aio_sigevent, sn->sn_id); 97 98 __sigev_list_lock(); 99 __sigev_register(sn); 100 __sigev_list_unlock(); 101 102 sn->sn_dispatch = aio_dispatch; 103 ret = sysfunc(iocb); 104 iocb->aio_sigevent = saved_ev; 105 106 if (ret != 0) { 107 __sigev_list_lock(); 108 __sigev_delete_node(sn); 109 __sigev_list_unlock(); 110 } 111 return (ret); 112} 113 114int 115__aio_read(struct aiocb *iocb) 116{ 117 return aio_io(iocb, &__sys_aio_read); 118} 119 120int 121__aio_write(struct aiocb *iocb) 122{ 123 return aio_io(iocb, &__sys_aio_write); 124} 125 126int 127__aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout) 128{ 129 int ret = __sys_aio_waitcomplete(iocbp, timeout); 130 131 if (*iocbp) { 132 if ((*iocbp)->aio_sigevent.sigev_notify == SIGEV_THREAD) { 133 __sigev_list_lock(); 134 __sigev_delete(SI_ASYNCIO, (sigev_id_t)(*iocbp)); 135 __sigev_list_unlock(); 136 } 137 } 138 139 return (ret); 140} 141 142int 143__aio_return(struct aiocb *iocb) 144{ 145 int ret = __sys_aio_return(iocb); 146 int err = __sys_aio_error(iocb); 147 148 if (err != EINPROGRESS && 149 iocb->aio_sigevent.sigev_notify == SIGEV_THREAD) { 150 __sigev_list_lock(); 151 __sigev_delete(SI_ASYNCIO, (sigev_id_t)iocb); 152 __sigev_list_unlock(); 153 } 154 155 return (ret); 156} 157