xref: /freebsd/lib/librt/aio.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice unmodified, this list of conditions, and the following
12  *    disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  *
30  */
31 
32 #include <sys/cdefs.h>
33 #include <sys/types.h>
34 #include <sys/syscall.h>
35 #include <sys/aio.h>
36 
37 #include "namespace.h"
38 #include <errno.h>
39 #include <stddef.h>
40 #include <signal.h>
41 #include "sigev_thread.h"
42 #include "un-namespace.h"
43 
44 __weak_reference(__aio_read, aio_read);
45 __weak_reference(__aio_readv, aio_readv);
46 __weak_reference(__aio_write, aio_write);
47 __weak_reference(__aio_writev, aio_writev);
48 __weak_reference(__aio_return, aio_return);
49 __weak_reference(__aio_waitcomplete, aio_waitcomplete);
50 __weak_reference(__aio_fsync, aio_fsync);
51 __weak_reference(__lio_listio, lio_listio);
52 
53 typedef void (*aio_func)(union sigval val, struct aiocb *iocb);
54 
55 extern int __sys_aio_read(struct aiocb *iocb);
56 extern int __sys_aio_readv(struct aiocb *iocb);
57 extern int __sys_aio_write(struct aiocb *iocb);
58 extern int __sys_aio_writev(struct aiocb *iocb);
59 extern ssize_t __sys_aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout);
60 extern ssize_t __sys_aio_return(struct aiocb *iocb);
61 extern int __sys_aio_error(struct aiocb *iocb);
62 extern int __sys_aio_fsync(int op, struct aiocb *iocb);
63 extern int __sys_lio_listio(int mode, struct aiocb * const list[], int nent,
64     struct sigevent *sig);
65 
66 static void
67 aio_dispatch(struct sigev_node *sn)
68 {
69 	aio_func f = sn->sn_func;
70 
71 	f(sn->sn_value, (struct aiocb *)sn->sn_id);
72 }
73 
74 static int
75 aio_sigev_alloc(sigev_id_t id, struct sigevent *sigevent,
76     struct sigev_node **sn, struct sigevent *saved_ev)
77 {
78 	if (__sigev_check_init()) {
79 		/* This might be that thread library is not enabled. */
80 		errno = EINVAL;
81 		return (-1);
82 	}
83 
84 	*sn = __sigev_alloc(SI_ASYNCIO, sigevent, NULL, 1);
85 	if (*sn == NULL) {
86 		errno = EAGAIN;
87 		return (-1);
88 	}
89 
90 	*saved_ev = *sigevent;
91 	(*sn)->sn_id = id;
92 	__sigev_get_sigevent(*sn, sigevent, (*sn)->sn_id);
93 	(*sn)->sn_dispatch = aio_dispatch;
94 
95 	__sigev_list_lock();
96 	__sigev_register(*sn);
97 	__sigev_list_unlock();
98 
99 	return (0);
100 }
101 
102 static int
103 aio_io(struct aiocb *iocb, int (*sysfunc)(struct aiocb *iocb))
104 {
105 	struct sigev_node *sn;
106 	struct sigevent saved_ev;
107 	int ret, err;
108 
109 	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD) {
110 		ret = sysfunc(iocb);
111 		return (ret);
112 	}
113 
114 	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
115 			      &saved_ev);
116 	if (ret)
117 		return (ret);
118 	ret = sysfunc(iocb);
119 	iocb->aio_sigevent = saved_ev;
120 	if (ret != 0) {
121 		err = errno;
122 		__sigev_list_lock();
123 		__sigev_delete_node(sn);
124 		__sigev_list_unlock();
125 		errno = err;
126 	}
127 	return (ret);
128 }
129 
130 int
131 __aio_read(struct aiocb *iocb)
132 {
133 
134 	return aio_io(iocb, &__sys_aio_read);
135 }
136 
137 int
138 __aio_readv(struct aiocb *iocb)
139 {
140 
141 	return aio_io(iocb, &__sys_aio_readv);
142 }
143 
144 int
145 __aio_write(struct aiocb *iocb)
146 {
147 
148 	return aio_io(iocb, &__sys_aio_write);
149 }
150 
151 int
152 __aio_writev(struct aiocb *iocb)
153 {
154 
155 	return aio_io(iocb, &__sys_aio_writev);
156 }
157 
158 ssize_t
159 __aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout)
160 {
161 	ssize_t ret;
162 	int err;
163 
164 	ret = __sys_aio_waitcomplete(iocbp, timeout);
165 	if (*iocbp) {
166 		if ((*iocbp)->aio_sigevent.sigev_notify == SIGEV_THREAD) {
167 			err = errno;
168 			__sigev_list_lock();
169 			__sigev_delete(SI_ASYNCIO, (sigev_id_t)(*iocbp));
170 			__sigev_list_unlock();
171 			errno = err;
172 		}
173 	}
174 
175 	return (ret);
176 }
177 
178 ssize_t
179 __aio_return(struct aiocb *iocb)
180 {
181 
182 	if (iocb->aio_sigevent.sigev_notify == SIGEV_THREAD) {
183 		if (__sys_aio_error(iocb) == EINPROGRESS) {
184 			/*
185 			 * Fail with EINVAL to match the semantics of
186 			 * __sys_aio_return() for an in-progress
187 			 * request.
188 			 */
189 			errno = EINVAL;
190 			return (-1);
191 		}
192 		__sigev_list_lock();
193 		__sigev_delete(SI_ASYNCIO, (sigev_id_t)iocb);
194 		__sigev_list_unlock();
195 	}
196 
197 	return __sys_aio_return(iocb);
198 }
199 
200 int
201 __aio_fsync(int op, struct aiocb *iocb)
202 {
203 	struct sigev_node *sn;
204 	struct sigevent saved_ev;
205 	int ret, err;
206 
207 	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD)
208 		return __sys_aio_fsync(op, iocb);
209 
210 	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
211 			      &saved_ev);
212 	if (ret)
213 		return (ret);
214 	ret = __sys_aio_fsync(op, iocb);
215 	iocb->aio_sigevent = saved_ev;
216 	if (ret != 0) {
217 		err = errno;
218 		__sigev_list_lock();
219 		__sigev_delete_node(sn);
220 		__sigev_list_unlock();
221 		errno = err;
222 	}
223 	return (ret);
224 }
225 
226 int
227 __lio_listio(int mode, struct aiocb * const list[], int nent,
228     struct sigevent *sig)
229 {
230 	struct sigev_node *sn;
231 	struct sigevent saved_ev;
232 	int ret, err;
233 
234 	if (sig == NULL || sig->sigev_notify != SIGEV_THREAD)
235 		return (__sys_lio_listio(mode, list, nent, sig));
236 
237 	ret = aio_sigev_alloc((sigev_id_t)list, sig, &sn, &saved_ev);
238 	if (ret)
239 		return (ret);
240 	ret = __sys_lio_listio(mode, list, nent, sig);
241 	*sig = saved_ev;
242 	if (ret != 0) {
243 		err = errno;
244 		__sigev_list_lock();
245 		__sigev_delete_node(sn);
246 		__sigev_list_unlock();
247 		errno = err;
248 	}
249 	return (ret);
250 }
251