xref: /netbsd-src/sys/kern/kern_stub.c (revision 466a16a118933bd295a8a104f095714fadf9cf68)
1 /*	$NetBSD: kern_stub.c,v 1.15 2008/11/20 09:30:32 ad Exp $	*/
2 
3 /*-
4  * Copyright (c) 2007, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * Copyright (c) 1982, 1986, 1991, 1993
31  *	The Regents of the University of California.  All rights reserved.
32  *
33  * Redistribution and use in source and binary forms, with or without
34  * modification, are permitted provided that the following conditions
35  * are met:
36  * 1. Redistributions of source code must retain the above copyright
37  *    notice, this list of conditions and the following disclaimer.
38  * 2. Redistributions in binary form must reproduce the above copyright
39  *    notice, this list of conditions and the following disclaimer in the
40  *    documentation and/or other materials provided with the distribution.
41  * 3. Neither the name of the University nor the names of its contributors
42  *    may be used to endorse or promote products derived from this software
43  *    without specific prior written permission.
44  *
45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55  * SUCH DAMAGE.
56  *
57  *	@(#)subr_xxx.c	8.3 (Berkeley) 3/29/95
58  */
59 
60 /*
61  * Stubs for system calls and facilities not included in the system.
62  */
63 
64 #include <sys/cdefs.h>
65 __KERNEL_RCSID(0, "$NetBSD: kern_stub.c,v 1.15 2008/11/20 09:30:32 ad Exp $");
66 
67 #include "opt_ptrace.h"
68 #include "opt_ktrace.h"
69 #include "opt_sa.h"
70 
71 /* XXX To get syscall prototypes. */
72 #define SYSVSHM
73 #define SYSVSEM
74 #define SYSVMSG
75 
76 #include <sys/param.h>
77 #include <sys/kernel.h>
78 #include <sys/proc.h>
79 #include <sys/signalvar.h>
80 #include <sys/syscall.h>
81 #include <sys/syscallargs.h>
82 #include <sys/syscallvar.h>
83 #include <sys/ktrace.h>
84 #include <sys/intr.h>
85 #include <sys/cpu.h>
86 #include <sys/module.h>
87 
88 /*
89  * Nonexistent system call-- signal process (may want to handle it).  Flag
90  * error in case process won't see signal immediately (blocked or ignored).
91  */
92 #ifndef PTRACE
93 __weak_alias(sys_ptrace,sys_nosys);
94 #endif	/* PTRACE */
95 
96 /*
97  * ktrace stubs.  ktruser() goes to enosys as we want to fail the syscall,
98  * but not kill the process: utrace() is a debugging feature.
99  */
100 #ifndef KTRACE
101 __weak_alias(ktr_csw,nullop);		/* Probes */
102 __weak_alias(ktr_emul,nullop);
103 __weak_alias(ktr_geniov,nullop);
104 __weak_alias(ktr_genio,nullop);
105 __weak_alias(ktr_mibio,nullop);
106 __weak_alias(ktr_namei,nullop);
107 __weak_alias(ktr_namei2,nullop);
108 __weak_alias(ktr_psig,nullop);
109 __weak_alias(ktr_saupcall,nullop);
110 __weak_alias(ktr_syscall,nullop);
111 __weak_alias(ktr_sysret,nullop);
112 __weak_alias(ktr_kuser,nullop);
113 __weak_alias(ktr_mmsg,nullop);
114 __weak_alias(ktr_mib,nullop);
115 __weak_alias(ktr_mool,nullop);
116 __weak_alias(ktr_execarg,nullop);
117 __weak_alias(ktr_execenv,nullop);
118 
119 __weak_alias(sys_fktrace,sys_nosys);	/* Syscalls */
120 __weak_alias(sys_ktrace,sys_nosys);
121 __weak_alias(sys_utrace,sys_nosys);
122 
123 int	ktrace_on;			/* Misc */
124 __weak_alias(ktruser,enosys);
125 __weak_alias(ktr_point,nullop);
126 #endif	/* KTRACE */
127 
128 #if !defined(KERN_SA)
129 /*
130  * Scheduler activations system calls.  These need to remain, even when
131  * KERN_SA isn't defined, until libc's major version is bumped.
132  */
133 __strong_alias(sys_sa_register,sys_nosys);
134 __strong_alias(sys_sa_stacks,sys_nosys);
135 __strong_alias(sys_sa_enable,sys_nosys);
136 __strong_alias(sys_sa_setconcurrency,sys_nosys);
137 __strong_alias(sys_sa_yield,sys_nosys);
138 __strong_alias(sys_sa_preempt,sys_nosys);
139 __strong_alias(sys_sa_unblockyield,sys_nosys);
140 
141 /*
142  * Stubs for compat_netbsd32.
143  */
144 __strong_alias(dosa_register,sys_nosys);
145 __strong_alias(sa_stacks1,sys_nosys);
146 #endif
147 
148 /*
149  * Stubs for architectures that do not support kernel preemption.
150  */
151 #ifndef __HAVE_PREEMPTION
152 bool
153 cpu_kpreempt_enter(uintptr_t where, int s)
154 {
155 
156 	return false;
157 }
158 
159 void
160 cpu_kpreempt_exit(uintptr_t where)
161 {
162 
163 }
164 
165 bool
166 cpu_kpreempt_disabled(void)
167 {
168 
169 	return true;
170 }
171 #else
172 # ifndef MULTIPROCESSOR
173 #   error __HAVE_PREEMPTION requires MULTIPROCESSOR
174 # endif
175 #endif	/* !__HAVE_PREEMPTION */
176 
177 int
178 sys_nosys(struct lwp *l, const void *v, register_t *retval)
179 {
180 
181 	mutex_enter(proc_lock);
182 	psignal(l->l_proc, SIGSYS);
183 	mutex_exit(proc_lock);
184 	return ENOSYS;
185 }
186 
187 int
188 sys_nomodule(struct lwp *l, const void *v, register_t *retval)
189 {
190 #ifdef MODULAR
191 	static struct {
192 		u_int		al_code;
193 		const char	*al_module;
194 	} const autoload[] = {
195 	    { SYS_aio_cancel, "aio" },
196 	    { SYS_aio_error, "aio" },
197 	    { SYS_aio_fsync, "aio" },
198 	    { SYS_aio_read, "aio" },
199 	    { SYS_aio_return, "aio" },
200 	    { SYS_aio_suspend, "aio" },
201 	    { SYS_aio_write, "aio" },
202 	    { SYS_lio_listio, "aio" },
203 	    { SYS_compat_43_fstat43, "compat" },
204 	    { SYS_compat_43_lstat43, "compat" },
205 	    { SYS_compat_43_oaccept, "compat" },
206 	    { SYS_compat_43_ocreat, "compat" },
207 	    { SYS_compat_43_oftruncate, "compat" },
208 	    { SYS_compat_43_ogetdirentries, "compat" },
209 	    { SYS_compat_43_ogetdtablesize, "compat" },
210 	    { SYS_compat_43_ogethostid, "compat" },
211 	    { SYS_compat_43_ogethostname, "compat" },
212 	    { SYS_compat_43_ogetkerninfo, "compat" },
213 	    { SYS_compat_43_ogetpagesize, "compat" },
214 	    { SYS_compat_43_ogetpeername, "compat" },
215 	    { SYS_compat_43_ogetrlimit, "compat" },
216 	    { SYS_compat_43_ogetsockname, "compat" },
217 	    { SYS_compat_43_okillpg, "compat" },
218 	    { SYS_compat_43_olseek, "compat" },
219 	    { SYS_compat_43_ommap, "compat" },
220 	    { SYS_compat_43_oquota, "compat" },
221 	    { SYS_compat_43_orecv, "compat" },
222 	    { SYS_compat_43_orecvfrom, "compat" },
223 	    { SYS_compat_43_orecvmsg, "compat" },
224 	    { SYS_compat_43_osend, "compat" },
225 	    { SYS_compat_43_osendmsg, "compat" },
226 	    { SYS_compat_43_osethostid, "compat" },
227 	    { SYS_compat_43_osethostname, "compat" },
228 	    { SYS_compat_43_osetrlimit, "compat" },
229 	    { SYS_compat_43_osigblock, "compat" },
230 	    { SYS_compat_43_osigsetmask, "compat" },
231 	    { SYS_compat_43_osigstack, "compat" },
232 	    { SYS_compat_43_osigvec, "compat" },
233 	    { SYS_compat_43_otruncate, "compat" },
234 	    { SYS_compat_43_owait, "compat" },
235 	    { SYS_compat_43_stat43, "compat" },
236 	    { SYS_compat_09_ogetdomainname, "compat" },
237 	    { SYS_compat_09_osetdomainname, "compat" },
238 	    { SYS_compat_09_ouname, "compat" },
239 #ifndef _LP64
240 	    { SYS_compat_10_omsgsys, "compat" },
241 	    { SYS_compat_10_osemsys, "compat" },
242 	    { SYS_compat_10_oshmsys, "compat" },
243 #endif
244 	    { SYS_compat_12_fstat12, "compat" },
245 	    { SYS_compat_12_getdirentries, "compat" },
246 	    { SYS_compat_12_lstat12, "compat" },
247 	    { SYS_compat_12_msync, "compat" },
248 	    { SYS_compat_12_oreboot, "compat" },
249 	    { SYS_compat_12_oswapon, "compat" },
250 	    { SYS_compat_12_stat12, "compat" },
251 	    { SYS_compat_13_sigaction13, "compat" },
252 	    { SYS_compat_13_sigaltstack13, "compat" },
253 	    { SYS_compat_13_sigpending13, "compat" },
254 	    { SYS_compat_13_sigprocmask13, "compat" },
255 	    { SYS_compat_13_sigreturn13, "compat" },
256 	    { SYS_compat_13_sigsuspend13, "compat" },
257 	    { SYS_compat_14___semctl, "compat" },
258 	    { SYS_compat_14_msgctl, "compat" },
259 	    { SYS_compat_14_shmctl, "compat" },
260 	    { SYS_compat_16___sigaction14, "compat" },
261 	    { SYS_compat_16___sigreturn14, "compat" },
262 	    { SYS_compat_20_fhstatfs, "compat" },
263 	    { SYS_compat_20_fstatfs, "compat" },
264 	    { SYS_compat_20_getfsstat, "compat" },
265 	    { SYS_compat_20_statfs, "compat" },
266 	    { SYS_compat_30___fhstat30, "compat" },
267 	    { SYS_compat_30___fstat13, "compat" },
268 	    { SYS_compat_30___lstat13, "compat" },
269 	    { SYS_compat_30___stat13, "compat" },
270 	    { SYS_compat_30_fhopen, "compat" },
271 	    { SYS_compat_30_fhstat, "compat" },
272 	    { SYS_compat_30_fhstatvfs1, "compat" },
273 	    { SYS_compat_30_getdents, "compat" },
274 	    { SYS_compat_30_getfh, "compat" },
275 	    { SYS_compat_30_socket, "compat" },
276 	    { SYS_compat_40_mount, "compat" },
277 	    { SYS__ksem_init, "ksem" },
278 	    { SYS__ksem_open, "ksem" },
279 	    { SYS__ksem_unlink, "ksem" },
280 	    { SYS__ksem_close, "ksem" },
281 	    { SYS__ksem_post, "ksem" },
282 	    { SYS__ksem_wait, "ksem" },
283 	    { SYS__ksem_trywait, "ksem" },
284 	    { SYS__ksem_getvalue, "ksem" },
285 	    { SYS__ksem_destroy, "ksem" },
286 	    { SYS_nfssvc, "nfsserver" },
287 	};
288 	const struct sysent *sy;
289 	const struct emul *em;
290 	int code, i;
291 
292 	/*
293 	 * Restart the syscall if we interrupted a module unload that
294 	 * failed.  Acquiring module_lock delays us until any unload
295 	 * has been completed or rolled back.
296 	 */
297 	mutex_enter(&module_lock);
298 	sy = l->l_sysent;
299 	if (sy->sy_call != sys_nomodule) {
300 		mutex_exit(&module_lock);
301 		return ERESTART;
302 	}
303 	/*
304 	 * Try to autoload a module to satisfy the request.  If it
305 	 * works, retry the request.
306 	 */
307 	em = l->l_proc->p_emul;
308 	if (em == &emul_netbsd) {
309 		code = sy - em->e_sysent;
310 		for (i = 0; i < __arraycount(autoload); i++) {
311 			if (autoload[i].al_code != code) {
312 				continue;
313 			}
314 			if (module_autoload(autoload[i].al_module,
315 			    MODULE_CLASS_ANY) != 0 ||
316 			    sy->sy_call == sys_nomodule) {
317 			    	break;
318 			}
319 			mutex_exit(&module_lock);
320 			return ERESTART;
321 		}
322 	}
323 	mutex_exit(&module_lock);
324 #endif	/* MODULAR */
325 
326 	return sys_nosys(l, v, retval);
327 }
328 
329 /*
330  * Unsupported device function (e.g. writing to read-only device).
331  */
332 int
333 enodev(void)
334 {
335 
336 	return (ENODEV);
337 }
338 
339 /*
340  * Unconfigured device function; driver not configured.
341  */
342 int
343 enxio(void)
344 {
345 
346 	return (ENXIO);
347 }
348 
349 /*
350  * Unsupported ioctl function.
351  */
352 int
353 enoioctl(void)
354 {
355 
356 	return (ENOTTY);
357 }
358 
359 /*
360  * Unsupported system function.
361  * This is used for an otherwise-reasonable operation
362  * that is not supported by the current system binary.
363  */
364 int
365 enosys(void)
366 {
367 
368 	return (ENOSYS);
369 }
370 
371 /*
372  * Return error for operation not supported
373  * on a specific object or file type.
374  */
375 int
376 eopnotsupp(void)
377 {
378 
379 	return (EOPNOTSUPP);
380 }
381 
382 /*
383  * Generic null operation, always returns success.
384  */
385 /*ARGSUSED*/
386 int
387 nullop(void *v)
388 {
389 
390 	return (0);
391 }
392