xref: /freebsd/lib/librt/aio.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
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/types.h>
31 #include <sys/syscall.h>
32 #include <sys/aio.h>
33 
34 #include "namespace.h"
35 #include <errno.h>
36 #include <stddef.h>
37 #include <signal.h>
38 #include "sigev_thread.h"
39 #include "un-namespace.h"
40 
41 __weak_reference(__aio_read, aio_read);
42 __weak_reference(__aio_readv, aio_readv);
43 __weak_reference(__aio_write, aio_write);
44 __weak_reference(__aio_writev, aio_writev);
45 __weak_reference(__aio_return, aio_return);
46 __weak_reference(__aio_waitcomplete, aio_waitcomplete);
47 __weak_reference(__aio_fsync, aio_fsync);
48 __weak_reference(__lio_listio, lio_listio);
49 
50 typedef void (*aio_func)(union sigval val, struct aiocb *iocb);
51 
52 extern int __sys_aio_read(struct aiocb *iocb);
53 extern int __sys_aio_readv(struct aiocb *iocb);
54 extern int __sys_aio_write(struct aiocb *iocb);
55 extern int __sys_aio_writev(struct aiocb *iocb);
56 extern ssize_t __sys_aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout);
57 extern ssize_t __sys_aio_return(struct aiocb *iocb);
58 extern int __sys_aio_error(struct aiocb *iocb);
59 extern int __sys_aio_fsync(int op, struct aiocb *iocb);
60 extern int __sys_lio_listio(int mode, struct aiocb * const list[], int nent,
61     struct sigevent *sig);
62 
63 static void
64 aio_dispatch(struct sigev_node *sn)
65 {
66 	aio_func f = sn->sn_func;
67 
68 	f(sn->sn_value, (struct aiocb *)sn->sn_id);
69 }
70 
71 static int
72 aio_sigev_alloc(sigev_id_t id, struct sigevent *sigevent,
73     struct sigev_node **sn, struct sigevent *saved_ev)
74 {
75 	if (__sigev_check_init()) {
76 		/* This might be that thread library is not enabled. */
77 		errno = EINVAL;
78 		return (-1);
79 	}
80 
81 	*sn = __sigev_alloc(SI_ASYNCIO, sigevent, NULL, 1);
82 	if (*sn == NULL) {
83 		errno = EAGAIN;
84 		return (-1);
85 	}
86 
87 	*saved_ev = *sigevent;
88 	(*sn)->sn_id = id;
89 	__sigev_get_sigevent(*sn, sigevent, (*sn)->sn_id);
90 	(*sn)->sn_dispatch = aio_dispatch;
91 
92 	__sigev_list_lock();
93 	__sigev_register(*sn);
94 	__sigev_list_unlock();
95 
96 	return (0);
97 }
98 
99 static int
100 aio_io(struct aiocb *iocb, int (*sysfunc)(struct aiocb *iocb))
101 {
102 	struct sigev_node *sn;
103 	struct sigevent saved_ev;
104 	int ret, err;
105 
106 	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD) {
107 		ret = sysfunc(iocb);
108 		return (ret);
109 	}
110 
111 	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
112 			      &saved_ev);
113 	if (ret)
114 		return (ret);
115 	ret = sysfunc(iocb);
116 	iocb->aio_sigevent = saved_ev;
117 	if (ret != 0) {
118 		err = errno;
119 		__sigev_list_lock();
120 		__sigev_delete_node(sn);
121 		__sigev_list_unlock();
122 		errno = err;
123 	}
124 	return (ret);
125 }
126 
127 int
128 __aio_read(struct aiocb *iocb)
129 {
130 
131 	return aio_io(iocb, &__sys_aio_read);
132 }
133 
134 int
135 __aio_readv(struct aiocb *iocb)
136 {
137 
138 	return aio_io(iocb, &__sys_aio_readv);
139 }
140 
141 int
142 __aio_write(struct aiocb *iocb)
143 {
144 
145 	return aio_io(iocb, &__sys_aio_write);
146 }
147 
148 int
149 __aio_writev(struct aiocb *iocb)
150 {
151 
152 	return aio_io(iocb, &__sys_aio_writev);
153 }
154 
155 ssize_t
156 __aio_waitcomplete(struct aiocb **iocbp, struct timespec *timeout)
157 {
158 	ssize_t ret;
159 	int err;
160 
161 	ret = __sys_aio_waitcomplete(iocbp, timeout);
162 	if (*iocbp) {
163 		if ((*iocbp)->aio_sigevent.sigev_notify == SIGEV_THREAD) {
164 			err = errno;
165 			__sigev_list_lock();
166 			__sigev_delete(SI_ASYNCIO, (sigev_id_t)(*iocbp));
167 			__sigev_list_unlock();
168 			errno = err;
169 		}
170 	}
171 
172 	return (ret);
173 }
174 
175 ssize_t
176 __aio_return(struct aiocb *iocb)
177 {
178 
179 	if (iocb->aio_sigevent.sigev_notify == SIGEV_THREAD) {
180 		if (__sys_aio_error(iocb) == EINPROGRESS) {
181 			/*
182 			 * Fail with EINVAL to match the semantics of
183 			 * __sys_aio_return() for an in-progress
184 			 * request.
185 			 */
186 			errno = EINVAL;
187 			return (-1);
188 		}
189 		__sigev_list_lock();
190 		__sigev_delete(SI_ASYNCIO, (sigev_id_t)iocb);
191 		__sigev_list_unlock();
192 	}
193 
194 	return __sys_aio_return(iocb);
195 }
196 
197 int
198 __aio_fsync(int op, struct aiocb *iocb)
199 {
200 	struct sigev_node *sn;
201 	struct sigevent saved_ev;
202 	int ret, err;
203 
204 	if (iocb->aio_sigevent.sigev_notify != SIGEV_THREAD)
205 		return __sys_aio_fsync(op, iocb);
206 
207 	ret = aio_sigev_alloc((sigev_id_t)iocb, &iocb->aio_sigevent, &sn,
208 			      &saved_ev);
209 	if (ret)
210 		return (ret);
211 	ret = __sys_aio_fsync(op, iocb);
212 	iocb->aio_sigevent = saved_ev;
213 	if (ret != 0) {
214 		err = errno;
215 		__sigev_list_lock();
216 		__sigev_delete_node(sn);
217 		__sigev_list_unlock();
218 		errno = err;
219 	}
220 	return (ret);
221 }
222 
223 int
224 __lio_listio(int mode, struct aiocb * const list[], int nent,
225     struct sigevent *sig)
226 {
227 	struct sigev_node *sn;
228 	struct sigevent saved_ev;
229 	int ret, err;
230 
231 	if (sig == NULL || sig->sigev_notify != SIGEV_THREAD)
232 		return (__sys_lio_listio(mode, list, nent, sig));
233 
234 	ret = aio_sigev_alloc((sigev_id_t)list, sig, &sn, &saved_ev);
235 	if (ret)
236 		return (ret);
237 	ret = __sys_lio_listio(mode, list, nent, sig);
238 	*sig = saved_ev;
239 	if (ret != 0) {
240 		err = errno;
241 		__sigev_list_lock();
242 		__sigev_delete_node(sn);
243 		__sigev_list_unlock();
244 		errno = err;
245 	}
246 	return (ret);
247 }
248