linux_pipe.c revision 1.65 
1/*	$NetBSD: linux_pipe.c,v 1.65 2011/04/14 00:59:06 christos 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 1.65 2011/04/14 00:59:06 christos Exp $");
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/kernel.h>
38#include <sys/malloc.h>
39#include <sys/mbuf.h>
40#include <sys/mman.h>
41#include <sys/mount.h>
42#include <sys/fcntl.h>
43#include <sys/filedesc.h>
44
45#include <sys/sched.h>
46#include <sys/syscallargs.h>
47
48#include <compat/linux/common/linux_types.h>
49#include <compat/linux/common/linux_mmap.h>
50#include <compat/linux/common/linux_signal.h>
51#include <compat/linux/common/linux_ipc.h>
52#include <compat/linux/common/linux_sem.h>
53#include <compat/linux/common/linux_fcntl.h>
54
55#include <compat/linux/linux_syscallargs.h>
56
57/* Used on: arm, i386, m68k, ppc, amd64 */
58/* Not used on: alpha, mips, sparc, sparc64 */
59/* Alpha, mips, sparc and sparc64 pass one of the fds in a register */
60
61/*
62 * NetBSD passes fd[0] in retval[0], and fd[1] in retval[1].
63 * Linux directly passes the pointer.
64 */
65static int
66linux_pipe_return(struct lwp *l, int *pfds, register_t *retval, int flags)
67{
68	int error;
69
70	if (sizeof(*retval) != sizeof(*pfds)) {
71		/* On amd64, sizeof(register_t) != sizeof(int) */
72		int rpfds[2];
73		rpfds[0] = (int)retval[0];
74		rpfds[1] = (int)retval[1];
75
76		if ((error = copyout(rpfds, pfds, sizeof(rpfds))))
77			return error;
78	} else {
79		if ((error = copyout(retval, pfds, 2 * sizeof(*pfds))))
80			return error;
81	}
82	if (flags & LINUX_O_CLOEXEC) {
83		fd_set_exclose(l, retval[0], true);
84		fd_set_exclose(l, retval[1], true);
85	}
86	retval[0] = 0;
87	return 0;
88}
89
90int
91linux_sys_pipe(struct lwp *l, const struct linux_sys_pipe_args *uap,
92    register_t *retval)
93{
94	/* {
95		syscallarg(int *) pfds;
96	} */
97	int error;
98
99	if ((error = pipe1(l, retval, 0)))
100		return error;
101
102	return linux_pipe_return(l, SCARG(uap, pfds), retval, 0);
103}
104
105int
106linux_sys_pipe2(struct lwp *l, const struct linux_sys_pipe2_args *uap,
107    register_t *retval)
108{
109	/* {
110		syscallarg(int *) pfds;
111		syscallarg(int) flags;
112	} */
113	int error;
114	int flag = 0;
115
116	switch (SCARG(uap, flags)) {
117	case LINUX_O_CLOEXEC:
118		break;
119	case LINUX_O_NONBLOCK:
120	case LINUX_O_NONBLOCK|LINUX_O_CLOEXEC:
121		flag = O_NONBLOCK;
122		break;
123	default:
124		return EINVAL;
125	}
126
127	if ((error = pipe1(l, retval, flag)))
128		return error;
129
130	return linux_pipe_return(l, SCARG(uap, pfds), retval,
131	    SCARG(uap, flags));
132}
133