xref: /netbsd-src/sys/compat/linux/arch/m68k/linux_machdep.c (revision d48f14661dda8638fee055ba15d35bdfb29b9fa8)
1 /*	$NetBSD: linux_machdep.c,v 1.27 2006/05/15 13:11:00 yamt Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by ITOH Yasufumi.
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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.27 2006/05/15 13:11:00 yamt Exp $");
41 
42 #define COMPAT_LINUX 1
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/proc.h>
48 #include <sys/exec.h>
49 #include <sys/ioctl.h>
50 #include <sys/mount.h>
51 #include <sys/signal.h>
52 #include <sys/signalvar.h>
53 #include <sys/sa.h>
54 #include <sys/syscallargs.h>
55 #include <sys/kauth.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_ioctl.h>
63 #include <compat/linux/common/linux_exec.h>
64 #include <compat/linux/common/linux_machdep.h>
65 
66 #include <compat/linux/linux_syscall.h>
67 #include <compat/linux/linux_syscallargs.h>
68 
69 /* XXX should be in an include file somewhere */
70 #define CC_PURGE	1
71 #define CC_FLUSH	2
72 #define CC_IPURGE	4
73 #define CC_EXTPURGE	0x80000000
74 /* XXX end should be */
75 
76 extern short exframesize[];
77 
78 #ifdef DEBUG
79 extern int sigdebug;
80 extern int sigpid;
81 #define SDB_FOLLOW	0x01
82 #define SDB_KSTACK	0x02
83 #define SDB_FPSTATE	0x04
84 #endif
85 
86 void setup_linux_sigframe __P((struct frame *frame, int sig,
87     const sigset_t *mask, caddr_t usp));
88 void setup_linux_rt_sigframe __P((struct frame *frame, int sig,
89     const sigset_t *mask, caddr_t usp, struct lwp *l));
90 
91 /*
92  * Deal with some m68k-specific things in the Linux emulation code.
93  */
94 
95 /*
96  * Setup registers on program execution.
97  */
98 void
99 linux_setregs(l, epp, stack)
100 	struct lwp *l;
101 	struct exec_package *epp;
102 	u_long stack;
103 {
104 
105 	setregs(l, epp, stack);
106 }
107 
108 /*
109  * Setup signal frame for old signal interface.
110  */
111 void
112 setup_linux_sigframe(frame, sig, mask, usp)
113 	struct frame *frame;
114 	int sig;
115 	const sigset_t *mask;
116 	caddr_t usp;
117 {
118 	struct lwp *l = curlwp;
119 	struct proc *p = l->l_proc;
120 	struct linux_sigframe *fp, kf;
121 	short ft;
122 
123 	ft = frame->f_format;
124 
125 	/* Allocate space for the signal handler context on the user stack. */
126 	fp = (struct linux_sigframe *) usp;
127 	fp--;
128 
129 #ifdef DEBUG
130 	if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
131 		printf("setup_linux_sigframe(%d): sig %d ssp %p usp %p scp %p ft %d\n",
132 		       p->p_pid, sig, &ft, fp, &fp->sf_c.c_sc, ft);
133 #endif
134 
135 	/* Build stack frame. */
136 	kf.sf_psigtramp = fp->sf_sigtramp;	/* return addr for handler */
137 	kf.sf_signum = native_to_linux_signo[sig];
138 	kf.sf_code = frame->f_vector;		/* Does anyone use it? */
139 	kf.sf_scp = &fp->sf_c.c_sc;
140 
141 	/* The sigtramp code is on the stack frame on Linux/m68k. */
142 	kf.sf_sigtramp[0] = LINUX_SF_SIGTRAMP0;
143 	kf.sf_sigtramp[1] = LINUX_SF_SIGTRAMP1;
144 
145 	/*
146 	 * Save necessary hardware state.  Currently this includes:
147 	 *	- scratch registers
148 	 *	- original exception frame (if not a "normal" frame)
149 	 *	- FP coprocessor state
150 	 */
151 	kf.sf_c.c_sc.sc_d0 = frame->f_regs[D0];
152 	kf.sf_c.c_sc.sc_d1 = frame->f_regs[D1];
153 	kf.sf_c.c_sc.sc_a0 = frame->f_regs[A0];
154 	kf.sf_c.c_sc.sc_a1 = frame->f_regs[A1];
155 
156 	/* Clear for security (and initialize ss_format). */
157 	bzero(&kf.sf_c.c_sc.sc_ss, sizeof kf.sf_c.c_sc.sc_ss);
158 
159 	if (ft >= FMT4) {
160 #ifdef DEBUG
161 		if (ft > 15 || exframesize[ft] < 0)
162 			panic("setup_linux_sigframe: bogus frame type");
163 #endif
164 		kf.sf_c.c_sc.sc_ss.ss_format = ft;
165 		kf.sf_c.c_sc.sc_ss.ss_vector = frame->f_vector;
166 		bcopy(&frame->F_u, &kf.sf_c.c_sc.sc_ss.ss_frame,
167 			(size_t) exframesize[ft]);
168 		/*
169 		 * Leave an indicator that we need to clean up the kernel
170 		 * stack.  We do this by setting the "pad word" above the
171 		 * hardware stack frame to the amount the stack must be
172 		 * adjusted by.
173 		 *
174 		 * N.B. we increment rather than just set f_stackadj in
175 		 * case we are called from syscall when processing a
176 		 * sigreturn.  In that case, f_stackadj may be non-zero.
177 		 */
178 		frame->f_stackadj += exframesize[ft];
179 		frame->f_format = frame->f_vector = 0;
180 #ifdef DEBUG
181 		if (sigdebug & SDB_FOLLOW)
182 			printf("setup_linux_sigframe(%d): copy out %d of frame %d\n",
183 			       p->p_pid, exframesize[ft], ft);
184 #endif
185 	}
186 
187 	switch (fputype) {
188 	case FPU_NONE:
189 		break;
190 #ifdef M68060
191 	case FPU_68060:
192 		__asm("fsave %0" : "=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.FPF_u1)
193 			: : "memory");
194 		if (((struct fpframe060 *)&kf.sf_c.c_sc.sc_ss.ss_fpstate.FPF_u1)
195 					->fpf6_frmfmt != FPF6_FMT_NULL) {
196 			__asm("fmovem %%fp0-%%fp1,%0" :
197 				"=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.fpf_regs[0][0]));
198 			/*
199 			 * On 060,  "fmovem fpcr/fpsr/fpi,<ea>"  is
200 			 * emulated by software and slow.
201 			 */
202 			__asm("fmovem %%fpcr,%0; fmovem %%fpsr,%1; fmovem %%fpi,%2" :
203 				"=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.fpf_fpcr),
204 				"=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.fpf_fpsr),
205 				"=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.fpf_fpiar));
206 		}
207 		break;
208 #endif
209 	default:
210 		__asm("fsave %0" : "=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.FPF_u1)
211 			: : "memory");
212 		if (kf.sf_c.c_sc.sc_ss.ss_fpstate.fpf_version) {
213 			__asm("fmovem %%fp0-%%fp1,%0; fmovem %%fpcr/%%fpsr/%%fpi,%1" :
214 				"=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.fpf_regs[0][0]),
215 				"=m" (kf.sf_c.c_sc.sc_ss.ss_fpstate.fpf_fpcr)
216 				: : "memory");
217 		}
218 		break;
219 	}
220 #ifdef DEBUG
221 	if ((sigdebug & SDB_FPSTATE) && *(char *)&kf.sf_c.c_sc.sc_ss.ss_fpstate)
222 		printf("setup_linux_sigframe(%d): copy out FP state (%x) to %p\n",
223 		       p->p_pid, *(u_int *)&kf.sf_c.c_sc.sc_ss.ss_fpstate,
224 		       &kf.sf_c.c_sc.sc_ss.ss_fpstate);
225 #endif
226 
227 	/* Build the signal context to be used by sigreturn. */
228 #if LINUX__NSIG_WORDS > 1
229 	native_to_linux_old_extra_sigset(&kf.sf_c.c_sc.sc_mask,
230 	    kf.sf_c.c_extrasigmask, mask);
231 #else
232 	native_to_linux_old_sigset(&kf.sf_c.c_sc.sc_mask, mask);
233 #endif
234 	kf.sf_c.c_sc.sc_sp = frame->f_regs[SP];
235 	kf.sf_c.c_sc.sc_pc = frame->f_pc;
236 	kf.sf_c.c_sc.sc_ps = frame->f_sr;
237 
238 	if (copyout(&kf, fp, sizeof(struct linux_sigframe))) {
239 #ifdef DEBUG
240 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
241 			printf("setup_linux_sigframe(%d): copyout failed on sig %d\n",
242 			       p->p_pid, sig);
243 #endif
244 		/*
245 		 * Process has trashed its stack; give it a segmentation
246 		 * violation to halt it in its tracks.
247 		 */
248 		sigexit(l, SIGSEGV);
249 		/* NOTREACHED */
250 	}
251 
252 	/*
253 	 * The signal trampoline is on the signal frame.
254 	 * Clear the instruction cache in case of cached.
255 	 */
256 	cachectl1(CC_EXTPURGE | CC_IPURGE,
257 			(vaddr_t) fp->sf_sigtramp, sizeof fp->sf_sigtramp, p);
258 
259 	/* Set up the user stack pointer. */
260 	frame->f_regs[SP] = (int)fp;
261 
262 #ifdef DEBUG
263 	if (sigdebug & SDB_FOLLOW)
264 		printf("setup_linux_sigframe(%d): sig %d scp %p fp %p sc_sp %x\n",
265 		       p->p_pid, sig, kf.sf_scp, fp, kf.sf_c.c_sc.sc_sp);
266 #endif
267 }
268 
269 /*
270  * Setup signal frame for new RT signal interface.
271  */
272 void
273 setup_linux_rt_sigframe(frame, sig, mask, usp, l)
274 	struct frame *frame;
275 	int sig;
276 	const sigset_t *mask;
277 	caddr_t usp;
278 	struct lwp *l;
279 {
280 	struct proc *p = l->l_proc;
281 	struct linux_rt_sigframe *fp, kf;
282 	short ft;
283 
284 	ft = frame->f_format;
285 
286 	/* Allocate space for the signal handler context on the user stack. */
287 	fp = (struct linux_rt_sigframe *) usp;
288 	fp--;
289 
290 #ifdef DEBUG
291 	if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
292 		printf("setup_linux_rt_sigframe(%d): sig %d ssp %p usp %p ucp %p ft %d\n",
293 		       p->p_pid, sig, &ft, fp, &fp->sf_uc, ft);
294 #endif
295 
296 	/* Build stack frame. */
297 	kf.sf_psigtramp = fp->sf_sigtramp;	/* return addr for handler */
298 	kf.sf_signum = native_to_linux_signo[sig];
299 	kf.sf_pinfo = &fp->sf_info;
300 	kf.sf_puc = &fp->sf_uc;
301 
302 	/* The sigtramp code is on the stack frame on Linux/m68k. */
303 	kf.sf_sigtramp[0] = LINUX_RT_SF_SIGTRAMP0;
304 	kf.sf_sigtramp[1] = LINUX_RT_SF_SIGTRAMP1;
305 
306 	/* clear for security (and initialize uc_flags, ss_format, etc.). */
307 	bzero(&kf.sf_uc, sizeof(struct linux_ucontext));
308 
309 	/*
310 	 * Save necessary hardware state.  Currently this includes:
311 	 *	- general registers
312 	 *	- original exception frame (if not a "normal" frame)
313 	 *	- FP coprocessor state
314 	 */
315 	/* version of mcontext */
316 	kf.sf_uc.uc_mc.mc_version = LINUX_MCONTEXT_VERSION;
317 
318 	/* general registers and pc/sr */
319 	bcopy(frame->f_regs, kf.sf_uc.uc_mc.mc_gregs.gr_regs, sizeof(u_int)*16);
320 	kf.sf_uc.uc_mc.mc_gregs.gr_pc = frame->f_pc;
321 	kf.sf_uc.uc_mc.mc_gregs.gr_sr = frame->f_sr;
322 
323 	if (ft >= FMT4) {
324 #ifdef DEBUG
325 		if (ft > 15 || exframesize[ft] < 0)
326 			panic("setup_linux_rt_sigframe: bogus frame type");
327 #endif
328 		kf.sf_uc.uc_ss.ss_format = ft;
329 		kf.sf_uc.uc_ss.ss_vector = frame->f_vector;
330 		bcopy(&frame->F_u, &kf.sf_uc.uc_ss.ss_frame,
331 			(size_t) exframesize[ft]);
332 		/*
333 		 * Leave an indicator that we need to clean up the kernel
334 		 * stack.  We do this by setting the "pad word" above the
335 		 * hardware stack frame to the amount the stack must be
336 		 * adjusted by.
337 		 *
338 		 * N.B. we increment rather than just set f_stackadj in
339 		 * case we are called from syscall when processing a
340 		 * sigreturn.  In that case, f_stackadj may be non-zero.
341 		 */
342 		frame->f_stackadj += exframesize[ft];
343 		frame->f_format = frame->f_vector = 0;
344 #ifdef DEBUG
345 		if (sigdebug & SDB_FOLLOW)
346 			printf("setup_linux_rt_sigframe(%d): copy out %d of frame %d\n",
347 			       p->p_pid, exframesize[ft], ft);
348 #endif
349 	}
350 
351 	switch (fputype) {
352 	case FPU_NONE:
353 		break;
354 #ifdef M68060
355 	case FPU_68060:
356 		__asm("fsave %0" : "=m" (kf.sf_uc.uc_ss.ss_fpstate));
357 				/* See note below. */
358 		if (((struct fpframe060 *) &kf.sf_uc.uc_ss.ss_fpstate.FPF_u1)
359 					->fpf6_frmfmt != FPF6_FMT_NULL) {
360 			__asm("fmovem %%fp0-%%fp7,%0" :
361 				"=m" (kf.sf_uc.uc_mc.mc_fpregs.fpr_regs[0][0]));
362 			/*
363 			 * On 060,  "fmovem fpcr/fpsr/fpi,<ea>"  is
364 			 * emulated by software and slow.
365 			 */
366 			__asm("fmovem %%fpcr,%0; fmovem %%fpsr,%1; fmovem %%fpi,%2" :
367 				"=m" (kf.sf_uc.uc_mc.mc_fpregs.fpr_fpcr),
368 				"=m" (kf.sf_uc.uc_mc.mc_fpregs.fpr_fpsr),
369 				"=m" (kf.sf_uc.uc_mc.mc_fpregs.fpr_fpiar));
370 		}
371 		break;
372 #endif
373 	default:
374 		/*
375 		 * NOTE:  We give whole of the  "struct linux_rt_fpframe"
376 		 * to the __asm("fsave") argument; not the FPF_u1 element only.
377 		 * Unlike the non-RT version of this structure,
378 		 * this contains only the FPU state used by "fsave"
379 		 * (and whole of the information is in the structure).
380 		 * This gives the correct dependency information to the __asm(),
381 		 * and no "memory" is required to the ``clobberd'' list.
382 		 */
383 		__asm("fsave %0" : "=m" (kf.sf_uc.uc_ss.ss_fpstate));
384 		if (kf.sf_uc.uc_ss.ss_fpstate.fpf_version) {
385 			__asm("fmovem %%fp0-%%fp7,%0; fmovem %%fpcr/%%fpsr/%%fpi,%1" :
386 				"=m" (kf.sf_uc.uc_mc.mc_fpregs.fpr_regs[0][0]),
387 				"=m" (kf.sf_uc.uc_mc.mc_fpregs.fpr_fpcr)
388 				: : "memory");
389 		}
390 		break;
391 	}
392 #ifdef DEBUG
393 	if ((sigdebug & SDB_FPSTATE) && *(char *)&kf.sf_uc.uc_ss.ss_fpstate)
394 		printf("setup_linux_rt_sigframe(%d): copy out FP state (%x) to %p\n",
395 		       p->p_pid, *(u_int *)&kf.sf_uc.uc_ss.ss_fpstate,
396 		       &kf.sf_uc.uc_ss.ss_fpstate);
397 #endif
398 
399 	/*
400 	 * XXX XAX Create bogus siginfo data.  This can't really
401 	 * XXX be fixed until NetBSD has realtime signals.
402 	 * XXX Or we do the emuldata thing.
403 	 * XXX -erh
404 	 */
405 	bzero(&kf.sf_info, sizeof(struct linux_siginfo));
406 	kf.sf_info.lsi_signo = sig;
407 	kf.sf_info.lsi_code = LINUX_SI_USER;
408 	kf.sf_info.lsi_pid = p->p_pid;
409 	kf.sf_info.lsi_uid = kauth_cred_geteuid(p->p_cred);	/* Use real uid here? */
410 
411 	/* Build the signal context to be used by sigreturn. */
412 	native_to_linux_sigset(&kf.sf_uc.uc_sigmask, mask);
413 	kf.sf_uc.uc_stack.ss_sp = p->p_sigctx.ps_sigstk.ss_sp;
414 	kf.sf_uc.uc_stack.ss_flags =
415 		(p->p_sigctx.ps_sigstk.ss_flags & SS_ONSTACK ? LINUX_SS_ONSTACK : 0) |
416 		(p->p_sigctx.ps_sigstk.ss_flags & SS_DISABLE ? LINUX_SS_DISABLE : 0);
417 	kf.sf_uc.uc_stack.ss_size = p->p_sigctx.ps_sigstk.ss_size;
418 
419 	if (copyout(&kf, fp, sizeof(struct linux_rt_sigframe))) {
420 #ifdef DEBUG
421 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
422 			printf("setup_linux_rt_sigframe(%d): copyout failed on sig %d\n",
423 			       p->p_pid, sig);
424 #endif
425 		/*
426 		 * Process has trashed its stack; give it a segmentation
427 		 * violation to halt it in its tracks.
428 		 */
429 		sigexit(l, SIGSEGV);
430 		/* NOTREACHED */
431 	}
432 
433 	/*
434 	 * The signal trampoline is on the signal frame.
435 	 * Clear the instruction cache in case of cached.
436 	 */
437 	cachectl1(CC_EXTPURGE | CC_IPURGE,
438 			(vaddr_t) fp->sf_sigtramp, sizeof fp->sf_sigtramp, p);
439 
440 	/* Set up the user stack pointer. */
441 	frame->f_regs[SP] = (int)fp;
442 
443 #ifdef DEBUG
444 	if (sigdebug & SDB_FOLLOW)
445 		printf("setup_linux_rt_sigframe(%d): sig %d puc %p fp %p sc_sp %x\n",
446 		       p->p_pid, sig, kf.sf_puc, fp,
447 		       kf.sf_uc.uc_mc.mc_gregs.gr_regs[SP]);
448 #endif
449 }
450 
451 /*
452  * Send an interrupt to Linux process.
453  */
454 void
455 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
456 {
457 	/* u_long code = ksi->ksi_trap; */
458 	int sig = ksi->ksi_signo;
459 	struct lwp *l = curlwp;
460 	struct proc *p = l->l_proc;
461 	struct frame *frame = (struct frame *)l->l_md.md_regs;
462 	int onstack;
463 	/* user stack for signal context */
464 	caddr_t usp = getframe(l, sig, &onstack);
465 	sig_t catcher = SIGACTION(p, sig).sa_handler;
466 
467 	/* Setup the signal frame (and part of the trapframe). */
468 	if (SIGACTION(p, sig).sa_flags & SA_SIGINFO)
469 		setup_linux_rt_sigframe(frame, sig, mask, usp, l);
470 	else
471 		setup_linux_sigframe(frame, sig, mask, usp);
472 
473 	/* Call the signal handler. */
474 	frame->f_pc = (u_int) catcher;
475 
476 	/* Remember that we're now on the signal stack. */
477 	if (onstack)
478 		p->p_sigctx.ps_sigstk.ss_flags |= SS_ONSTACK;
479 
480 #ifdef DEBUG
481 	if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
482 		printf("linux_sendsig(%d): sig %d returns\n",
483 		       p->p_pid, sig);
484 #endif
485 }
486 
487 /*
488  * The linux_sys_sigreturn and linux_sys_rt_sigreturn
489  * system calls cleanup state after a signal
490  * has been taken.  Reset signal mask and stack
491  * state from context left by linux_sendsig (above).
492  * Return to previous pc and psl as specified by
493  * context left by linux_sendsig. Check carefully to
494  * make sure that the user has not modified the
495  * psl to gain improper privileges or to cause
496  * a machine fault.
497  *
498  * Note that the sigreturn system calls of Linux/m68k
499  * do not return on errors, but issue segmentation
500  * violation and terminate the process.
501  */
502 /* ARGSUSED */
503 int
504 linux_sys_sigreturn(l, v, retval)
505 	struct lwp *l;
506 	void *v;
507 	register_t *retval;
508 {
509 	struct proc *p = l->l_proc;
510 	struct frame *frame;
511 	struct linux_sigc2 tsigc2;	/* extra mask and sigcontext */
512 	struct linux_sigcontext *scp;	/* pointer to sigcontext */
513 	sigset_t mask;
514 	int sz = 0;			/* extra frame size */
515 	int usp;
516 
517 	/*
518 	 * sigreturn of Linux/m68k takes no arguments.
519 	 * The user stack points at struct linux_sigc2.
520 	 */
521 	frame = (struct frame *) l->l_md.md_regs;
522 	usp = frame->f_regs[SP];
523 	if (usp & 1)
524 		goto bad;
525 
526 #ifdef DEBUG
527 	if (sigdebug & SDB_FOLLOW)
528 		printf("linux_sys_sigreturn: pid %d, usp %p\n",
529 			p->p_pid, (caddr_t) usp);
530 #endif
531 
532 	/* Grab whole of the sigcontext. */
533 	if (copyin((caddr_t) usp, &tsigc2, sizeof tsigc2))
534 bad:		sigexit(l, SIGSEGV);
535 
536 	scp = &tsigc2.c_sc;
537 
538 	/*
539 	 * Check kernel stack and re-enter to syscall() if needed.
540 	 */
541 	if ((sz = scp->sc_ss.ss_format) != 0) {
542 		if ((sz = exframesize[sz]) < 0)
543 			goto bad;
544 		if (sz && frame->f_stackadj == 0) {
545 			/*
546 			 * Extra stack space is required but not allocated.
547 			 * Allocate and re-enter syscall().
548 			 */
549 			reenter_syscall(frame, sz);
550 			/* NOTREACHED */
551 		}
552 	}
553 #ifdef DEBUG
554 	/* reenter_syscall() doesn't adjust stack. */
555 	if (sz != frame->f_stackadj)
556 		panic("linux_sys_sigreturn: adj: %d != %d",
557 			sz, frame->f_stackadj);
558 #endif
559 
560 	/* Restore signal stack. */
561 	p->p_sigctx.ps_sigstk.ss_flags &= ~SS_ONSTACK;
562 
563 	/* Restore signal mask. */
564 #if LINUX__NSIG_WORDS > 1
565 	linux_old_extra_to_native_sigset(&mask, &scp->sc_mask,
566 					 tsigc2.c_extrasigmask);
567 #else
568 	linux_old_to_native_sigset(&scp->sc_mask, &mask);
569 #endif
570 	(void) sigprocmask1(p, SIG_SETMASK, &mask, 0);
571 
572 	/*
573 	 * Restore the user supplied information.
574 	 */
575 	frame->f_regs[SP] = scp->sc_sp;
576 	frame->f_regs[D0] = scp->sc_d0;
577 	frame->f_regs[D1] = scp->sc_d1;
578 	frame->f_regs[A0] = scp->sc_a0;
579 	frame->f_regs[A1] = scp->sc_a1;
580 	frame->f_pc = scp->sc_pc;
581 	/* Privileged bits of  sr  are silently ignored on Linux/m68k. */
582 	frame->f_sr = scp->sc_ps & ~(PSL_MBZ|PSL_IPL|PSL_S);
583 	/*
584 	 * Other registers are assumed to be unchanged,
585 	 * and not restored.
586 	 */
587 
588 	/*
589 	 * Restore long stack frames.  Note that we do not copy
590 	 * back the saved SR or PC, they were picked up above from
591 	 * the sigcontext structure.
592 	 */
593 	if (scp->sc_ss.ss_format) {
594 		frame->f_format = scp->sc_ss.ss_format;
595 		frame->f_vector = scp->sc_ss.ss_vector;
596 		if (frame->f_stackadj < sz)	/* just in case... */
597 			goto bad;
598 		frame->f_stackadj -= sz;
599 		bcopy(&scp->sc_ss.ss_frame, &frame->F_u, sz);
600 #ifdef DEBUG
601 		if (sigdebug & SDB_FOLLOW)
602 			printf("linux_sys_sigreturn(%d): copy in %d of frame type %d\n",
603 			       p->p_pid, sz, scp->sc_ss.ss_format);
604 #endif
605 	}
606 
607 	/*
608 	 * Finally we restore the original FP context.
609 	 */
610 	switch (fputype) {
611 	case FPU_NONE:
612 		break;
613 #ifdef M68060
614 	case FPU_68060:
615 		if (((struct fpframe060*)&scp->sc_ss.ss_fpstate.FPF_u1)
616 					->fpf6_frmfmt != FPF6_FMT_NULL) {
617 			/*
618 			 * On 060,  "fmovem <ea>,fpcr/fpsr/fpi"  is
619 			 * emulated by software and slow.
620 			 */
621 			__asm("fmovem %0,%%fpcr; fmovem %1,%%fpsr; fmovem %2,%%fpi"::
622 				"m" (scp->sc_ss.ss_fpstate.fpf_fpcr),
623 				"m" (scp->sc_ss.ss_fpstate.fpf_fpsr),
624 				"m" (scp->sc_ss.ss_fpstate.fpf_fpiar));
625 			__asm("fmovem %0,%%fp0-%%fp1" : :
626 				"m" (scp->sc_ss.ss_fpstate.fpf_regs[0][0]));
627 		}
628 		__asm("frestore %0" : : "m" (scp->sc_ss.ss_fpstate.FPF_u1));
629 		break;
630 #endif
631 	default:
632 		if (scp->sc_ss.ss_fpstate.fpf_version) {
633 			__asm("fmovem %0,%%fpcr/%%fpsr/%%fpi; fmovem %1,%%fp0-%%fp1"::
634 				"m" (scp->sc_ss.ss_fpstate.fpf_fpcr),
635 				"m" (scp->sc_ss.ss_fpstate.fpf_regs[0][0]));
636 		}
637 		__asm("frestore %0" : : "m" (scp->sc_ss.ss_fpstate.FPF_u1));
638 		break;
639 	}
640 
641 #ifdef DEBUG
642 	if ((sigdebug & SDB_FPSTATE) && *(char *)&scp->sc_ss.ss_fpstate)
643 		printf("linux_sys_sigreturn(%d): copied in FP state (%x) at %p\n",
644 		       p->p_pid, *(u_int *)&scp->sc_ss.ss_fpstate,
645 		       &scp->sc_ss.ss_fpstate);
646 	if ((sigdebug & SDB_FOLLOW) ||
647 	    ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid))
648 		printf("linux_sys_sigreturn(%d): returns\n", p->p_pid);
649 #endif
650 
651 	return EJUSTRETURN;
652 }
653 
654 /* ARGSUSED */
655 int
656 linux_sys_rt_sigreturn(l, v, retval)
657 	struct lwp *l;
658 	void *v;
659 	register_t *retval;
660 {
661 	struct proc *p = l->l_proc;
662 	struct frame *frame;
663 	struct linux_ucontext *ucp;	/* ucontext in user space */
664 	struct linux_ucontext tuc;	/* copy of *ucp */
665 	sigset_t mask;
666 	int sz = 0, error;		/* extra frame size */
667 
668 	/*
669 	 * rt_sigreturn of Linux/m68k takes no arguments.
670 	 * usp + 4 is a pointer to siginfo structure,
671 	 * usp + 8 is a pointer to ucontext structure.
672 	 */
673 	frame = (struct frame *) l->l_md.md_regs;
674 	error = copyin((caddr_t) frame->f_regs[SP] + 8, (void *) &ucp, sizeof(void *));
675 	if (error || (int) ucp & 1)
676 		goto bad;		/* error or odd address */
677 
678 #ifdef DEBUG
679 	if (sigdebug & SDB_FOLLOW)
680 		printf("linux_rt_sigreturn: pid %d, ucp %p\n", p->p_pid, ucp);
681 #endif
682 
683 	/* Grab whole of the ucontext. */
684 	if (copyin(ucp, &tuc, sizeof tuc))
685 bad:		sigexit(l, SIGSEGV);
686 
687 	/*
688 	 * Check kernel stack and re-enter to syscall() if needed.
689 	 */
690 	if ((sz = tuc.uc_ss.ss_format) != 0) {
691 		if ((sz = exframesize[sz]) < 0)
692 			goto bad;
693 		if (sz && frame->f_stackadj == 0) {
694 			/*
695 			 * Extra stack space is required but not allocated.
696 			 * Allocate and re-enter syscall().
697 			 */
698 			reenter_syscall(frame, sz);
699 			/* NOTREACHED */
700 		}
701 	}
702 #ifdef DEBUG
703 	/* reenter_syscall() doesn't adjust stack. */
704 	if (sz != frame->f_stackadj)
705 		panic("linux_sys_rt_sigreturn: adj: %d != %d",
706 			sz, frame->f_stackadj);
707 #endif
708 
709 	if (tuc.uc_mc.mc_version != LINUX_MCONTEXT_VERSION)
710 		goto bad;
711 
712 	/* Restore signal stack. */
713 	p->p_sigctx.ps_sigstk.ss_flags =
714 		(p->p_sigctx.ps_sigstk.ss_flags & ~SS_ONSTACK) |
715 		(tuc.uc_stack.ss_flags & LINUX_SS_ONSTACK ? SS_ONSTACK : 0);
716 
717 	/* Restore signal mask. */
718 	linux_to_native_sigset(&mask, &tuc.uc_sigmask);
719 	(void) sigprocmask1(p, SIG_SETMASK, &mask, 0);
720 
721 	/*
722 	 * Restore the user supplied information.
723 	 */
724 	bcopy(tuc.uc_mc.mc_gregs.gr_regs, frame->f_regs, sizeof(u_int)*16);
725 	frame->f_pc = tuc.uc_mc.mc_gregs.gr_pc;
726 	/* Privileged bits of  sr  are silently ignored on Linux/m68k. */
727 	frame->f_sr = tuc.uc_mc.mc_gregs.gr_sr & ~(PSL_MBZ|PSL_IPL|PSL_S);
728 
729 	/*
730 	 * Restore long stack frames.  Note that we do not copy
731 	 * back the saved SR or PC, they were picked up above from
732 	 * the ucontext structure.
733 	 */
734 	if (tuc.uc_ss.ss_format) {
735 		frame->f_format = tuc.uc_ss.ss_format;
736 		frame->f_vector = tuc.uc_ss.ss_vector;
737 		if (frame->f_stackadj < sz)	/* just in case... */
738 			goto bad;
739 		frame->f_stackadj -= sz;
740 		bcopy(&tuc.uc_ss.ss_frame, &frame->F_u, sz);
741 #ifdef DEBUG
742 		if (sigdebug & SDB_FOLLOW)
743 			printf("linux_sys_rt_sigreturn(%d): copy in %d of frame type %d\n",
744 			       p->p_pid, sz, tuc.uc_ss.ss_format);
745 #endif
746 	}
747 
748 	/*
749 	 * Finally we restore the original FP context.
750 	 */
751 	switch (fputype) {
752 	case FPU_NONE:
753 		break;
754 #ifdef M68060
755 	case FPU_68060:
756 		if (((struct fpframe060*)&tuc.uc_ss.ss_fpstate.FPF_u1)
757 					->fpf6_frmfmt != FPF6_FMT_NULL) {
758 			/*
759 			 * On 060,  "fmovem <ea>,fpcr/fpsr/fpi"  is
760 			 * emulated by software and slow.
761 			 */
762 			__asm("fmovem %0,%%fpcr; fmovem %1,%%fpsr; fmovem %2,%%fpi"::
763 				"m" (tuc.uc_mc.mc_fpregs.fpr_fpcr),
764 				"m" (tuc.uc_mc.mc_fpregs.fpr_fpsr),
765 				"m" (tuc.uc_mc.mc_fpregs.fpr_fpiar));
766 			__asm("fmovem %0,%%fp0-%%fp1" : :
767 				"m" (tuc.uc_mc.mc_fpregs.fpr_regs[0][0]));
768 		}
769 		__asm("frestore %0" : : "m" (tuc.uc_ss.ss_fpstate.FPF_u1));
770 		break;
771 #endif
772 	default:
773 		if (tuc.uc_ss.ss_fpstate.fpf_version) {
774 			__asm("fmovem %0,%%fpcr/%%fpsr/%%fpi; fmovem %1,%%fp0-%%fp1"::
775 				"m" (tuc.uc_mc.mc_fpregs.fpr_fpcr),
776 				"m" (tuc.uc_mc.mc_fpregs.fpr_regs[0][0]));
777 		}
778 		__asm("frestore %0" : : "m" (tuc.uc_ss.ss_fpstate.FPF_u1));
779 		break;
780 	}
781 
782 #ifdef DEBUG
783 	if ((sigdebug & SDB_FPSTATE) && *(char *)&tuc.uc_ss.ss_fpstate)
784 		printf("linux_rt_sigreturn(%d): copied in FP state (%x) at %p\n",
785 		       p->p_pid, *(u_int *)&tuc.uc_ss.ss_fpstate,
786 		       &tuc.uc_ss.ss_fpstate);
787 	if ((sigdebug & SDB_FOLLOW) ||
788 	    ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid))
789 		printf("linux_rt_sigreturn(%d): returns\n", p->p_pid);
790 #endif
791 
792 	return EJUSTRETURN;
793 }
794 
795 /*
796  * MPU cache operation of Linux/m68k,
797  * mainly used for dynamic linking.
798  */
799 
800 /* scope */
801 #define LINUX_FLUSH_SCOPE_LINE	1	/* a cache line */
802 #define LINUX_FLUSH_SCOPE_PAGE	2	/* a page */
803 #define LINUX_FLUSH_SCOPE_ALL	3	/* the whole cache */
804 /* cache */
805 #define LINUX_FLUSH_CACHE_DATA	1	/* flush and purge data cache */
806 #define LINUX_FLUSH_CACHE_INSN	2	/* purge instruction cache */
807 #define LINUX_FLUSH_CACHE_BOTH	3	/* both */
808 
809 /* ARGSUSED */
810 int
811 linux_sys_cacheflush(l, v, retval)
812 	struct lwp *l;
813 	void *v;
814 	register_t *retval;
815 {
816 	struct linux_sys_cacheflush_args /* {
817 		syscallarg(unsigned long)	addr;
818 		syscallarg(int)			scope;
819 		syscallarg(int)			cache;
820 		syscallarg(unsigned long)	len;
821 	} */ *uap = v;
822 	struct proc *p = l->l_proc;
823 	int scope, cache;
824 	vaddr_t addr;
825 	int len;
826 	int error;
827 
828 	scope = SCARG(uap, scope);
829 	cache = SCARG(uap, cache);
830 
831 	if (scope < LINUX_FLUSH_SCOPE_LINE || scope > LINUX_FLUSH_SCOPE_ALL
832 				|| cache & ~LINUX_FLUSH_CACHE_BOTH)
833 		return EINVAL;
834 
835 #if defined(M68040) || defined(M68060)
836 	addr = (vaddr_t) SCARG(uap, addr);
837 	len = (int) SCARG(uap, len);
838 #else
839 	/*
840 	 * We always flush entire cache on 68020/030
841 	 * and these values are not used afterwards.
842 	 */
843 	addr = 0;
844 	len = 0;
845 #endif
846 
847 	/*
848 	 * LINUX_FLUSH_SCOPE_ALL (flush whole cache) is limited to super users.
849 	 */
850 	if (scope == LINUX_FLUSH_SCOPE_ALL) {
851 		if ((error = kauth_authorize_generic(p->p_cred, KAUTH_GENERIC_ISSUSER, &p->p_acflag)) != 0)
852 			return error;
853 #if defined(M68040) || defined(M68060)
854 		/* entire cache */
855 		len = INT_MAX;
856 #endif
857 	}
858 
859 	error = 0;
860 	if (cache & LINUX_FLUSH_CACHE_DATA)
861 		if ((error = cachectl1(CC_EXTPURGE|CC_PURGE, addr, len, p)) !=0)
862 			return error;
863 	if (cache & LINUX_FLUSH_CACHE_INSN)
864 		error = cachectl1(CC_EXTPURGE|CC_IPURGE, addr, len, p);
865 
866 	return error;
867 }
868 
869 /*
870  * Convert NetBSD's devices to Linux's.
871  */
872 dev_t
873 linux_fakedev(dev, raw)
874 	dev_t dev;
875 	int raw;
876 {
877 
878 	/* do nothing for now */
879 	return dev;
880 }
881 
882 /*
883  * We come here in a last attempt to satisfy a Linux ioctl() call.
884  */
885 int
886 linux_machdepioctl(l, v, retval)
887 	struct lwp *l;
888 	void *v;
889 	register_t *retval;
890 {
891 	struct linux_sys_ioctl_args /* {
892 		syscallarg(int) fd;
893 		syscallarg(u_long) com;
894 		syscallarg(caddr_t) data;
895 	} */ *uap = v;
896 	struct sys_ioctl_args bia;
897 	u_long com;
898 
899 	SCARG(&bia, fd) = SCARG(uap, fd);
900 	SCARG(&bia, data) = SCARG(uap, data);
901 	com = SCARG(uap, com);
902 
903 	switch (com) {
904 
905 	/* do nothing for now */
906 
907 	default:
908 		printf("linux_machdepioctl: invalid ioctl %08lx\n", com);
909 		return EINVAL;
910 	}
911 	SCARG(&bia, com) = com;
912 	return sys_ioctl(l, &bia, retval);
913 }
914 
915 int
916 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
917 {
918 	return 0;
919 }
920