xref: /freebsd/lib/librt/aio.c (revision 5e3190f700637fcfc1a52daeaa4a031fdd2557c7)
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  */
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 <stddef.h>
38 #include <signal.h>
39 #include "sigev_thread.h"
40 #include "un-namespace.h"
41 
42 __weak_reference(__aio_read, aio_read);
43 __weak_reference(__aio_readv, aio_readv);
44 __weak_reference(__aio_write, aio_write);
45 __weak_reference(__aio_writev, aio_writev);
46 __weak_reference(__aio_return, aio_return);
47 __weak_reference(__aio_waitcomplete, aio_waitcomplete);
48 __weak_reference(__aio_fsync, aio_fsync);
49 __weak_reference(__lio_listio, lio_listio);
50 
51 typedef void (*aio_func)(union sigval val, struct aiocb *iocb);
52 
53 extern int __sys_aio_read(struct aiocb *iocb);
54 extern int __sys_aio_readv(struct aiocb *iocb);
55 extern int __sys_aio_write(struct aiocb *iocb);
56 extern int __sys_aio_writev(struct aiocb *iocb);
57 extern ssize_t __sys_aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout);
58 extern ssize_t __sys_aio_return(struct aiocb *iocb);
59 extern int __sys_aio_error(struct aiocb *iocb);
60 extern int __sys_aio_fsync(int op, struct aiocb *iocb);
61 extern int __sys_lio_listio(int mode, struct aiocb * const list[], int nent,
62     struct sigevent *sig);
63 
64 static void
65 aio_dispatch(struct sigev_node *sn)
66 {
67 	aio_func f = sn->sn_func;
68 
69 	f(sn->sn_value, (struct aiocb *)sn->sn_id);
70 }
71 
72 static int
73 aio_sigev_alloc(sigev_id_t id, struct sigevent *sigevent,
74     struct sigev_node **sn, struct sigevent *saved_ev)
75 {
76 	if (__sigev_check_init()) {
77 		/* This might be that thread library is not enabled. */
78 		errno = EINVAL;
79 		return (-1);
80 	}
81 
82 	*sn = __sigev_alloc(SI_ASYNCIO, sigevent, NULL, 1);
83 	if (*sn == NULL) {
84 		errno = EAGAIN;
85 		return (-1);
86 	}
87 
88 	*saved_ev = *sigevent;
89 	(*sn)->sn_id = id;
90 	__sigev_get_sigevent(*sn, sigevent, (*sn)->sn_id);
91 	(*sn)->sn_dispatch = aio_dispatch;
92 
93 	__sigev_list_lock();
94 	__sigev_register(*sn);
95 	__sigev_list_unlock();
96 
97 	return (0);
98 }
99 
100 static int
101 aio_io(struct aiocb *iocb, int (*sysfunc)(struct aiocb *iocb))
102 {
103 	struct sigev_node *sn;
104 	struct sigevent saved_ev;
105 	int ret, err;
106 
107 	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD) {
108 		ret = sysfunc(iocb);
109 		return (ret);
110 	}
111 
112 	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
113 			      &saved_ev);
114 	if (ret)
115 		return (ret);
116 	ret = sysfunc(iocb);
117 	iocb->aio_sigevent = saved_ev;
118 	if (ret != 0) {
119 		err = errno;
120 		__sigev_list_lock();
121 		__sigev_delete_node(sn);
122 		__sigev_list_unlock();
123 		errno = err;
124 	}
125 	return (ret);
126 }
127 
128 int
129 __aio_read(struct aiocb *iocb)
130 {
131 
132 	return aio_io(iocb, &__sys_aio_read);
133 }
134 
135 int
136 __aio_readv(struct aiocb *iocb)
137 {
138 
139 	return aio_io(iocb, &__sys_aio_readv);
140 }
141 
142 int
143 __aio_write(struct aiocb *iocb)
144 {
145 
146 	return aio_io(iocb, &__sys_aio_write);
147 }
148 
149 int
150 __aio_writev(struct aiocb *iocb)
151 {
152 
153 	return aio_io(iocb, &__sys_aio_writev);
154 }
155 
156 ssize_t
157 __aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout)
158 {
159 	ssize_t ret;
160 	int err;
161 
162 	ret = __sys_aio_waitcomplete(iocbp, timeout);
163 	if (*iocbp) {
164 		if ((*iocbp)->aio_sigevent.sigev_notify == SIGEV_THREAD) {
165 			err = errno;
166 			__sigev_list_lock();
167 			__sigev_delete(SI_ASYNCIO, (sigev_id_t)(*iocbp));
168 			__sigev_list_unlock();
169 			errno = err;
170 		}
171 	}
172 
173 	return (ret);
174 }
175 
176 ssize_t
177 __aio_return(struct aiocb *iocb)
178 {
179 
180 	if (iocb->aio_sigevent.sigev_notify == SIGEV_THREAD) {
181 		if (__sys_aio_error(iocb) == EINPROGRESS) {
182 			/*
183 			 * Fail with EINVAL to match the semantics of
184 			 * __sys_aio_return() for an in-progress
185 			 * request.
186 			 */
187 			errno = EINVAL;
188 			return (-1);
189 		}
190 		__sigev_list_lock();
191 		__sigev_delete(SI_ASYNCIO, (sigev_id_t)iocb);
192 		__sigev_list_unlock();
193 	}
194 
195 	return __sys_aio_return(iocb);
196 }
197 
198 int
199 __aio_fsync(int op, struct aiocb *iocb)
200 {
201 	struct sigev_node *sn;
202 	struct sigevent saved_ev;
203 	int ret, err;
204 
205 	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD)
206 		return __sys_aio_fsync(op, iocb);
207 
208 	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
209 			      &saved_ev);
210 	if (ret)
211 		return (ret);
212 	ret = __sys_aio_fsync(op, iocb);
213 	iocb->aio_sigevent = saved_ev;
214 	if (ret != 0) {
215 		err = errno;
216 		__sigev_list_lock();
217 		__sigev_delete_node(sn);
218 		__sigev_list_unlock();
219 		errno = err;
220 	}
221 	return (ret);
222 }
223 
224 int
225 __lio_listio(int mode, struct aiocb * const list[], int nent,
226     struct sigevent *sig)
227 {
228 	struct sigev_node *sn;
229 	struct sigevent saved_ev;
230 	int ret, err;
231 
232 	if (sig == NULL || sig->sigev_notify != SIGEV_THREAD)
233 		return (__sys_lio_listio(mode, list, nent, sig));
234 
235 	ret = aio_sigev_alloc((sigev_id_t)list, sig, &sn, &saved_ev);
236 	if (ret)
237 		return (ret);
238 	ret = __sys_lio_listio(mode, list, nent, sig);
239 	*sig = saved_ev;
240 	if (ret != 0) {
241 		err = errno;
242 		__sigev_list_lock();
243 		__sigev_delete_node(sn);
244 		__sigev_list_unlock();
245 		errno = err;
246 	}
247 	return (ret);
248 }
249