linux32_exec.c revision 1.4 
1/*	$NetBSD: linux32_exec.c,v 1.4 2007/02/09 21:55:21 ad Exp $ */
2
3/*-
4 * Copyright (c) 1994-2006 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,
9 * Thor Lancelot Simon, and Emmanuel Dreyfus.
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: linux32_exec.c,v 1.4 2007/02/09 21:55:21 ad 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#include <sys/ptrace.h>		/* For proc_reparent() */
57
58#include <uvm/uvm_extern.h>
59
60#include <machine/cpu.h>
61#include <machine/reg.h>
62
63#include <compat/linux/common/linux_types.h>
64#include <compat/linux/common/linux_emuldata.h>
65
66#include <compat/linux32/common/linux32_exec.h>
67#include <compat/linux32/common/linux32_types.h>
68#include <compat/linux32/common/linux32_signal.h>
69#include <compat/linux32/common/linux32_machdep.h>
70
71#include <compat/linux32/linux32_syscallargs.h>
72#include <compat/linux32/linux32_syscall.h>
73
74extern char linux32_sigcode[1];
75extern char linux32_rt_sigcode[1];
76extern char linux32_esigcode[1];
77
78extern struct sysent linux32_sysent[];
79extern const char * const linux32_syscallnames[];
80
81static void linux32_e_proc_exec __P((struct proc *, struct exec_package *));
82static void linux32_e_proc_fork __P((struct proc *, struct proc *, int));
83static void linux32_e_proc_exit __P((struct proc *));
84static void linux32_e_proc_init __P((struct proc *, struct proc *, int));
85
86#ifdef LINUX32_NPTL
87void linux32_userret __P((struct lwp *, void *));
88void linux_nptl_proc_fork __P((struct proc *, struct proc *,
89	void (luserret)(struct lwp *, void *)));
90void linux_nptl_proc_exit __P((struct proc *));
91void linux_nptl_proc_init __P((struct proc *, struct proc *));
92#endif
93
94/*
95 * Emulation switch.
96 */
97
98struct uvm_object *emul_linux32_object;
99
100const struct emul emul_linux32 = {
101	"linux32",
102	"/emul/linux32",
103#ifndef __HAVE_MINIMAL_EMUL
104	0,
105	NULL,
106	LINUX32_SYS_syscall,
107	LINUX32_SYS_NSYSENT,
108#endif
109	linux32_sysent,
110	linux32_syscallnames,
111	linux32_sendsig,
112	trapsignal,
113	NULL,
114	linux32_sigcode,
115	linux32_esigcode,
116	&emul_linux32_object,
117	linux32_setregs,
118	linux32_e_proc_exec,
119	linux32_e_proc_fork,
120	linux32_e_proc_exit,
121	NULL,
122	NULL,
123	linux32_syscall_intern,
124	NULL,
125	NULL,
126	netbsd32_vm_default_addr,
127};
128
129static void
130linux32_e_proc_init(p, parent, forkflags)
131	struct proc *p, *parent;
132	int forkflags;
133{
134	struct linux_emuldata *e = p->p_emuldata;
135	struct linux_emuldata_shared *s;
136	struct linux_emuldata *ep = NULL;
137
138	if (!e) {
139		/* allocate new Linux emuldata */
140		MALLOC(e, void *, sizeof(struct linux_emuldata),
141			M_EMULDATA, M_WAITOK);
142	} else  {
143		e->s->refs--;
144		if (e->s->refs == 0)
145			FREE(e->s, M_EMULDATA);
146	}
147
148	memset(e, '\0', sizeof(struct linux_emuldata));
149
150	e->proc = p;
151
152	if (parent)
153		ep = parent->p_emuldata;
154
155	if (forkflags & FORK_SHAREVM) {
156#ifdef DIAGNOSTIC
157		if (ep == NULL) {
158			killproc(p, "FORK_SHAREVM while emuldata is NULL\n");
159			return;
160		}
161#endif
162		s = ep->s;
163		s->refs++;
164	} else {
165		struct vmspace *vm;
166
167		MALLOC(s, void *, sizeof(struct linux_emuldata_shared),
168			M_EMULDATA, M_WAITOK);
169		s->refs = 1;
170
171		/*
172		 * Set the process idea of the break to the real value.
173		 * For fork, we use parent's vmspace since our's
174		 * is not setup at the time of this call and is going
175		 * to be copy of parent's anyway. For exec, just
176		 * use our own vmspace.
177		 */
178		vm = (parent) ? parent->p_vmspace : p->p_vmspace;
179		s->p_break = vm->vm_daddr + ctob(vm->vm_dsize);
180
181		/*
182		 * Linux threads are emulated as NetBSD processes (not lwp)
183		 * We use native PID for Linux TID. The Linux TID is the
184		 * PID of the first process in the group. It is stored
185		 * here
186		 */
187		s->group_pid = p->p_pid;
188
189		/*
190		 * Initialize the list of threads in the group
191		 */
192		LIST_INIT(&s->threads);
193
194		s->xstat = 0;
195		s->flags = 0;
196	}
197
198	e->s = s;
199
200	/*
201	 * Add this thread in the group thread list
202	 */
203	LIST_INSERT_HEAD(&s->threads, e, threads);
204
205#ifdef LINUX32_NPTL
206	linux_nptl_proc_init(p, parent);
207#endif /* LINUX32_NPTL */
208
209	p->p_emuldata = e;
210}
211
212/*
213 * Allocate new per-process structures. Called when executing Linux
214 * process. We can reuse the old emuldata - if it's not null,
215 * the executed process is of same emulation as original forked one.
216 */
217static void
218linux32_e_proc_exec(p, epp)
219	struct proc *p;
220	struct exec_package *epp;
221{
222	/* exec, use our vmspace */
223	linux32_e_proc_init(p, NULL, 0);
224}
225
226/*
227 * Emulation per-process exit hook.
228 */
229static void
230linux32_e_proc_exit(p)
231	struct proc *p;
232{
233	struct linux_emuldata *e = p->p_emuldata;
234
235#ifdef LINUX32_NPTL
236	linux_nptl_proc_exit(p);
237#endif /* LINUX32_NPTL */
238
239	/* Remove the thread for the group thread list */
240	LIST_REMOVE(e, threads);
241
242	/* free Linux emuldata and set the pointer to null */
243	e->s->refs--;
244	if (e->s->refs == 0)
245		FREE(e->s, M_EMULDATA);
246	FREE(e, M_EMULDATA);
247	p->p_emuldata = NULL;
248}
249
250/*
251 * Emulation fork hook.
252 */
253static void
254linux32_e_proc_fork(p, parent, forkflags)
255	struct proc *p, *parent;
256	int forkflags;
257{
258	/*
259	 * The new process might share some vmspace-related stuff
260	 * with parent, depending on fork flags (CLONE_VM et.al).
261	 * Force allocation of new base emuldata, and share the
262	 * VM-related parts only if necessary.
263	 */
264	p->p_emuldata = NULL;
265	linux32_e_proc_init(p, parent, forkflags);
266
267#ifdef LINUX32_NPTL
268	linux_nptl_proc_fork(p, parent, (*linux32_userret));
269#endif
270
271	return;
272}
273
274#ifdef LINUX32_NPTL
275void
276linux32_userret(l, arg)
277	struct lwp *l;
278	void *arg;
279{
280	struct proc *p = l->l_proc;
281	struct linux_emuldata *led = p->p_emuldata;
282	int error;
283
284	p->p_userret = NULL;
285
286	/* LINUX_CLONE_CHILD_SETTID: copy child's TID to child's memory  */
287	if (led->clone_flags & LINUX_CLONE_CHILD_SETTID) {
288		if ((error = copyout(&l->l_proc->p_pid,
289		    led->child_tidptr,  sizeof(l->l_proc->p_pid))) != 0)
290			printf("linux32_userret: LINUX_CLONE_CHILD_SETTID "
291			    "failed (led->child_tidptr = %p, p->p_pid = %d)\n",
292			    led->child_tidptr, p->p_pid);
293	}
294
295	/* LINUX_CLONE_SETTLS: allocate a new TLS */
296	if (led->clone_flags & LINUX_CLONE_SETTLS) {
297		if (linux32_set_newtls(l, linux32_get_newtls(l)) != 0)
298			printf("linux32_userret: linux32_set_tls failed");
299	}
300
301	return;
302}
303#endif /* LINUX32_NPTL */
304