xref: /netbsd-src/sys/compat/linux32/common/linux32_exec.c (revision 0df165c04d0a9ca1adde9ed2b890344c937954a6)
1 /*	$NetBSD: linux32_exec.c,v 1.7 2007/10/19 12:16:39 ad Exp $ */
2 
3 /*-
4  * Copyright (c) 1994-2007 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 1.7 2007/10/19 12:16:39 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 <sys/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 
74 extern char linux32_sigcode[1];
75 extern char linux32_rt_sigcode[1];
76 extern char linux32_esigcode[1];
77 
78 extern struct sysent linux32_sysent[];
79 extern const char * const linux32_syscallnames[];
80 
81 static void linux32_e_proc_exec __P((struct proc *, struct exec_package *));
82 static void linux32_e_proc_fork __P((struct proc *, struct proc *, int));
83 static void linux32_e_proc_exit __P((struct proc *));
84 static void linux32_e_proc_init __P((struct proc *, struct proc *, int));
85 
86 #ifdef LINUX32_NPTL
87 void linux32_userret(void);
88 void linux_nptl_proc_fork(struct proc *, struct proc *, void (*luserret)(void));
89 void linux_nptl_proc_exit __P((struct proc *));
90 void linux_nptl_proc_init __P((struct proc *, struct proc *));
91 #endif
92 
93 /*
94  * Emulation switch.
95  */
96 
97 struct uvm_object *emul_linux32_object;
98 
99 const struct emul emul_linux32 = {
100 	"linux32",
101 	"/emul/linux32",
102 #ifndef __HAVE_MINIMAL_EMUL
103 	0,
104 	NULL,
105 	LINUX32_SYS_syscall,
106 	LINUX32_SYS_NSYSENT,
107 #endif
108 	linux32_sysent,
109 	linux32_syscallnames,
110 	linux32_sendsig,
111 	trapsignal,
112 	NULL,
113 	linux32_sigcode,
114 	linux32_esigcode,
115 	&emul_linux32_object,
116 	linux32_setregs,
117 	linux32_e_proc_exec,
118 	linux32_e_proc_fork,
119 	linux32_e_proc_exit,
120 	NULL,
121 	NULL,
122 	linux32_syscall_intern,
123 	NULL,
124 	NULL,
125 	netbsd32_vm_default_addr,
126 };
127 
128 static void
129 linux32_e_proc_init(p, parent, forkflags)
130 	struct proc *p, *parent;
131 	int forkflags;
132 {
133 	struct linux_emuldata *e = p->p_emuldata;
134 	struct linux_emuldata_shared *s;
135 	struct linux_emuldata *ep = NULL;
136 
137 	if (!e) {
138 		/* allocate new Linux emuldata */
139 		MALLOC(e, void *, sizeof(struct linux_emuldata),
140 			M_EMULDATA, M_WAITOK);
141 	} else  {
142 		e->s->refs--;
143 		if (e->s->refs == 0)
144 			FREE(e->s, M_EMULDATA);
145 	}
146 
147 	memset(e, '\0', sizeof(struct linux_emuldata));
148 
149 	e->proc = p;
150 
151 	if (parent)
152 		ep = parent->p_emuldata;
153 
154 	if (forkflags & FORK_SHAREVM) {
155 #ifdef DIAGNOSTIC
156 		if (ep == NULL) {
157 			killproc(p, "FORK_SHAREVM while emuldata is NULL\n");
158 			return;
159 		}
160 #endif
161 		s = ep->s;
162 		s->refs++;
163 	} else {
164 		struct vmspace *vm;
165 
166 		MALLOC(s, void *, sizeof(struct linux_emuldata_shared),
167 			M_EMULDATA, M_WAITOK);
168 		s->refs = 1;
169 
170 		/*
171 		 * Set the process idea of the break to the real value.
172 		 * For fork, we use parent's vmspace since our's
173 		 * is not setup at the time of this call and is going
174 		 * to be copy of parent's anyway. For exec, just
175 		 * use our own vmspace.
176 		 */
177 		vm = (parent) ? parent->p_vmspace : p->p_vmspace;
178 		s->p_break = (char *)vm->vm_daddr + ctob(vm->vm_dsize);
179 
180 		/*
181 		 * Linux threads are emulated as NetBSD processes (not lwp)
182 		 * We use native PID for Linux TID. The Linux TID is the
183 		 * PID of the first process in the group. It is stored
184 		 * here
185 		 */
186 		s->group_pid = p->p_pid;
187 
188 		/*
189 		 * Initialize the list of threads in the group
190 		 */
191 		LIST_INIT(&s->threads);
192 
193 		s->xstat = 0;
194 		s->flags = 0;
195 	}
196 
197 	e->s = s;
198 
199 	/*
200 	 * Add this thread in the group thread list
201 	 */
202 	LIST_INSERT_HEAD(&s->threads, e, threads);
203 
204 #ifdef LINUX32_NPTL
205 	linux_nptl_proc_init(p, parent);
206 #endif /* LINUX32_NPTL */
207 
208 	p->p_emuldata = e;
209 }
210 
211 /*
212  * Allocate new per-process structures. Called when executing Linux
213  * process. We can reuse the old emuldata - if it's not null,
214  * the executed process is of same emulation as original forked one.
215  */
216 static void
217 linux32_e_proc_exec(p, epp)
218 	struct proc *p;
219 	struct exec_package *epp;
220 {
221 	/* exec, use our vmspace */
222 	linux32_e_proc_init(p, NULL, 0);
223 }
224 
225 /*
226  * Emulation per-process exit hook.
227  */
228 static void
229 linux32_e_proc_exit(p)
230 	struct proc *p;
231 {
232 	struct linux_emuldata *e = p->p_emuldata;
233 
234 #ifdef LINUX32_NPTL
235 	linux_nptl_proc_exit(p);
236 #endif /* LINUX32_NPTL */
237 
238 	/* Remove the thread for the group thread list */
239 	LIST_REMOVE(e, threads);
240 
241 	/* free Linux emuldata and set the pointer to null */
242 	e->s->refs--;
243 	if (e->s->refs == 0)
244 		FREE(e->s, M_EMULDATA);
245 	FREE(e, M_EMULDATA);
246 	p->p_emuldata = NULL;
247 }
248 
249 /*
250  * Emulation fork hook.
251  */
252 static void
253 linux32_e_proc_fork(p, parent, forkflags)
254 	struct proc *p, *parent;
255 	int forkflags;
256 {
257 	/*
258 	 * The new process might share some vmspace-related stuff
259 	 * with parent, depending on fork flags (CLONE_VM et.al).
260 	 * Force allocation of new base emuldata, and share the
261 	 * VM-related parts only if necessary.
262 	 */
263 	p->p_emuldata = NULL;
264 	linux32_e_proc_init(p, parent, forkflags);
265 
266 #ifdef LINUX32_NPTL
267 	linux_nptl_proc_fork(p, parent, linux32_userret);
268 #endif
269 
270 	return;
271 }
272 
273 #ifdef LINUX32_NPTL
274 void
275 linux32_userret(void)
276 {
277 	struct lwp *l = curlwp;
278 	struct proc *p = l->l_proc;
279 	struct linux_emuldata *led = p->p_emuldata;
280 	int error;
281 
282 	/* LINUX_CLONE_CHILD_SETTID: copy child's TID to child's memory  */
283 	if (led->clone_flags & LINUX_CLONE_CHILD_SETTID) {
284 		if ((error = copyout(&l->l_proc->p_pid,
285 		    led->child_tidptr,  sizeof(l->l_proc->p_pid))) != 0)
286 			printf("linux32_userret: LINUX_CLONE_CHILD_SETTID "
287 			    "failed (led->child_tidptr = %p, p->p_pid = %d)\n",
288 			    led->child_tidptr, p->p_pid);
289 	}
290 
291 	/* LINUX_CLONE_SETTLS: allocate a new TLS */
292 	if (led->clone_flags & LINUX_CLONE_SETTLS) {
293 		if (linux32_set_newtls(l, linux32_get_newtls(l)) != 0)
294 			printf("linux32_userret: linux32_set_tls failed");
295 	}
296 
297 	return;
298 }
299 #endif /* LINUX32_NPTL */
300