linux_exec.c revision 1.56
1/*	$NetBSD: linux_exec.c,v 1.56 2002/01/17 21:19:22 bjh21 Exp $	*/
2
3/*-
4 * Copyright (c) 1994, 1995, 1998, 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas, Frank van der Linden, Eric Haszlakiewicz and
9 * Thor Lancelot Simon.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 *    must display the following acknowledgement:
21 *        This product includes software developed by the NetBSD
22 *        Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 *    contributors may be used to endorse or promote products derived
25 *    from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40#include <sys/cdefs.h>
41__KERNEL_RCSID(0, "$NetBSD: linux_exec.c,v 1.56 2002/01/17 21:19:22 bjh21 Exp $");
42
43#include <sys/param.h>
44#include <sys/systm.h>
45#include <sys/kernel.h>
46#include <sys/proc.h>
47#include <sys/malloc.h>
48#include <sys/namei.h>
49#include <sys/vnode.h>
50#include <sys/mount.h>
51#include <sys/exec.h>
52#include <sys/exec_elf.h>
53
54#include <sys/mman.h>
55#include <sys/syscallargs.h>
56
57#include <machine/cpu.h>
58#include <machine/reg.h>
59
60#include <compat/linux/common/linux_types.h>
61#include <compat/linux/common/linux_signal.h>
62#include <compat/linux/common/linux_util.h>
63#include <compat/linux/common/linux_exec.h>
64#include <compat/linux/common/linux_machdep.h>
65
66#include <compat/linux/linux_syscallargs.h>
67#include <compat/linux/linux_syscall.h>
68#include <compat/linux/common/linux_misc.h>
69#include <compat/linux/common/linux_errno.h>
70#include <compat/linux/common/linux_emuldata.h>
71
72extern struct sysent linux_sysent[];
73extern const char * const linux_syscallnames[];
74extern char linux_sigcode[], linux_esigcode[];
75#ifndef __HAVE_SYSCALL_INTERN
76void LINUX_SYSCALL_FUNCTION __P((void));
77#endif
78
79static void linux_e_proc_exec __P((struct proc *, struct exec_package *));
80static void linux_e_proc_fork __P((struct proc *, struct proc *));
81static void linux_e_proc_exit __P((struct proc *));
82static void linux_e_proc_init __P((struct proc *, struct vmspace *));
83
84/*
85 * Execve(2). Just check the alternate emulation path, and pass it on
86 * to the NetBSD execve().
87 */
88int
89linux_sys_execve(p, v, retval)
90	struct proc *p;
91	void *v;
92	register_t *retval;
93{
94	struct linux_sys_execve_args /* {
95		syscallarg(const char *) path;
96		syscallarg(char **) argv;
97		syscallarg(char **) envp;
98	} */ *uap = v;
99	struct sys_execve_args ap;
100	caddr_t sg;
101
102	sg = stackgap_init(p->p_emul);
103	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
104
105	SCARG(&ap, path) = SCARG(uap, path);
106	SCARG(&ap, argp) = SCARG(uap, argp);
107	SCARG(&ap, envp) = SCARG(uap, envp);
108
109	return sys_execve(p, &ap, retval);
110}
111
112/*
113 * Emulation switch.
114 */
115const struct emul emul_linux = {
116	"linux",
117	"/emul/linux",
118#ifndef __HAVE_MINIMAL_EMUL
119	0,
120	(int*)native_to_linux_errno,
121	LINUX_SYS_syscall,
122	LINUX_SYS_MAXSYSCALL,
123#endif
124	linux_sysent,
125	linux_syscallnames,
126	linux_sendsig,
127	linux_trapsignal,
128	linux_sigcode,
129	linux_esigcode,
130	linux_setregs,
131	linux_e_proc_exec,
132	linux_e_proc_fork,
133	linux_e_proc_exit,
134#ifdef __HAVE_SYSCALL_INTERN
135	linux_syscall_intern,
136#else
137	LINUX_SYSCALL_FUNCTION,
138#endif
139};
140
141static void
142linux_e_proc_init(p, vmspace)
143	struct proc *p;
144	struct vmspace *vmspace;
145{
146	if (!p->p_emuldata) {
147		/* allocate new Linux emuldata */
148		MALLOC(p->p_emuldata, void *, sizeof(struct linux_emuldata),
149			M_EMULDATA, M_WAITOK);
150	}
151
152	memset(p->p_emuldata, '\0', sizeof(struct linux_emuldata));
153
154	/* Set the process idea of the break to the real value */
155	((struct linux_emuldata*)(p->p_emuldata))->p_break =
156	    vmspace->vm_daddr + ctob(vmspace->vm_dsize);
157}
158
159/*
160 * Allocate per-process structures. Called when executing Linux
161 * process. We can reuse the old emuldata - if it's not null,
162 * the executed process is of same emulation as original forked one.
163 */
164static void
165linux_e_proc_exec(p, epp)
166	struct proc *p;
167	struct exec_package *epp;
168{
169	/* exec, use our vmspace */
170	linux_e_proc_init(p, p->p_vmspace);
171}
172
173/*
174 * Emulation per-process exit hook.
175 */
176static void
177linux_e_proc_exit(p)
178	struct proc *p;
179{
180	/* free Linux emuldata and set the pointer to null */
181	FREE(p->p_emuldata, M_EMULDATA);
182	p->p_emuldata = NULL;
183}
184
185/*
186 * Emulation fork hook.
187 */
188static void
189linux_e_proc_fork(p, parent)
190	struct proc *p, *parent;
191{
192	/*
193	 * It could be desirable to copy some stuff from parent's
194	 * emuldata. We don't need anything like that for now.
195	 * So just allocate new emuldata for the new process.
196	 */
197	p->p_emuldata = NULL;
198
199	/* fork, use parent's vmspace (our vmspace may not be setup yet) */
200	linux_e_proc_init(p, parent->p_vmspace);
201}
202