xref: /netbsd-src/sys/compat/linux/common/linux_pipe.c (revision 3feacbccbd4c8b6fd5f19c8e34474c4c3f8923d7)
1 /*	$NetBSD: linux_pipe.c,v 1.67 2014/11/09 17:48:08 maxv Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Frank van der Linden and Eric Haszlakiewicz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: linux_pipe.c,v 1.67 2014/11/09 17:48:08 maxv Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/mbuf.h>
39 #include <sys/mman.h>
40 #include <sys/mount.h>
41 #include <sys/fcntl.h>
42 #include <sys/filedesc.h>
43 
44 #include <sys/sched.h>
45 #include <sys/syscallargs.h>
46 
47 #include <compat/linux/common/linux_types.h>
48 #include <compat/linux/common/linux_mmap.h>
49 #include <compat/linux/common/linux_signal.h>
50 #include <compat/linux/common/linux_ipc.h>
51 #include <compat/linux/common/linux_sem.h>
52 #include <compat/linux/common/linux_fcntl.h>
53 
54 #include <compat/linux/linux_syscallargs.h>
55 
56 /* Used on: arm, i386, m68k, ppc, amd64 */
57 /* Not used on: alpha, mips, sparc, sparc64 */
58 /* Alpha, mips, sparc and sparc64 pass one of the fds in a register */
59 
60 /*
61  * NetBSD passes fd[0] in retval[0], and fd[1] in retval[1].
62  * Linux directly passes the pointer.
63  */
64 static int
65 linux_pipe_return(struct lwp *l, int *pfds, register_t *retval)
66 {
67 	int error;
68 
69 	if (sizeof(*retval) != sizeof(*pfds)) {
70 		/* On amd64, sizeof(register_t) != sizeof(int) */
71 		int rpfds[2];
72 		rpfds[0] = (int)retval[0];
73 		rpfds[1] = (int)retval[1];
74 
75 		if ((error = copyout(rpfds, pfds, sizeof(rpfds))))
76 			return error;
77 	} else {
78 		if ((error = copyout(retval, pfds, 2 * sizeof(*pfds))))
79 			return error;
80 	}
81 	retval[0] = 0;
82 	return 0;
83 }
84 
85 int
86 linux_sys_pipe(struct lwp *l, const struct linux_sys_pipe_args *uap,
87     register_t *retval)
88 {
89 	/* {
90 		syscallarg(int *) pfds;
91 	} */
92 	int error;
93 
94 	if ((error = pipe1(l, retval, 0)))
95 		return error;
96 
97 	return linux_pipe_return(l, SCARG(uap, pfds), retval);
98 }
99 
100 int
101 linux_sys_pipe2(struct lwp *l, const struct linux_sys_pipe2_args *uap,
102     register_t *retval)
103 {
104 	/* {
105 		syscallarg(int *) pfds;
106 		syscallarg(int) flags;
107 	} */
108 	int error, flags;
109 
110 	flags = linux_to_bsd_ioflags(SCARG(uap, flags));
111 	if ((flags & ~(O_CLOEXEC|O_NONBLOCK)) != 0)
112 		return EINVAL;
113 
114 	if ((error = pipe1(l, retval, flags)))
115 		return error;
116 
117 	return linux_pipe_return(l, SCARG(uap, pfds), retval);
118 }
119