1 /*	$NetBSD: linux_machdep.c,v 1.25 2002/09/25 22:21:33 thorpej 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 Eric Haszlakiewicz.
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  * Based on sys/arch/i386/i386/linux_machdep.c:
39  *	linux_machdep.c,v 1.42 1998/09/11 12:50:06 mycroft Exp
40  *	written by Frank van der Linden
41  *
42  */
43 
44 #include <sys/cdefs.h>
45 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.25 2002/09/25 22:21:33 thorpej Exp $");
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/signalvar.h>
50 #include <sys/kernel.h>
51 #include <sys/proc.h>
52 #include <sys/user.h>
53 #include <sys/buf.h>
54 #include <sys/reboot.h>
55 #include <sys/conf.h>
56 #include <sys/exec.h>
57 #include <sys/file.h>
58 #include <sys/callout.h>
59 #include <sys/malloc.h>
60 #include <sys/mbuf.h>
61 #include <sys/msgbuf.h>
62 #include <sys/mount.h>
63 #include <sys/vnode.h>
64 #include <sys/device.h>
65 #include <sys/syscallargs.h>
66 #include <sys/filedesc.h>
67 #include <sys/exec_elf.h>
68 #include <sys/ioctl.h>
69 
70 #include <uvm/uvm_extern.h>
71 
72 #include <compat/linux/common/linux_types.h>
73 #include <compat/linux/common/linux_signal.h>
74 #include <compat/linux/common/linux_siginfo.h>
75 #include <compat/linux/common/linux_util.h>
76 #include <compat/linux/common/linux_ioctl.h>
77 #include <compat/linux/common/linux_exec.h>
78 #include <compat/linux/common/linux_machdep.h>
79 #include <compat/linux/common/linux_emuldata.h>
80 
81 #include <compat/linux/linux_syscallargs.h>
82 
83 #include <machine/alpha.h>
84 #include <machine/reg.h>
85 
86 #if defined(_KERNEL_OPT)
87 #include "wsdisplay.h"
88 #endif
89 #if (NWSDISPLAY >0)
90 #include <dev/wscons/wsdisplay_usl_io.h>
91 #endif
92 #ifdef DEBUG
93 #include <machine/sigdebug.h>
94 #endif
95 
96 /*
97  * Deal with some alpha-specific things in the Linux emulation code.
98  */
99 
100 void
101 linux_setregs(p, epp, stack)
102 	struct proc *p;
103 	struct exec_package *epp;
104 	u_long stack;
105 {
106 #ifdef DEBUG
107 	struct trapframe *tfp = p->p_md.md_tf;
108 #endif
109 
110 	setregs(p, epp, stack);
111 #ifdef DEBUG
112 	/*
113 	 * Linux has registers set to zero on entry; for DEBUG kernels
114 	 * the alpha setregs() fills registers with 0xbabefacedeadbeef.
115 	 */
116 	memset(tfp->tf_regs, 0, FRAME_SIZE * sizeof tfp->tf_regs[0]);
117 #endif
118 }
119 
120 void setup_linux_rt_sigframe(tf, sig, mask)
121 	struct trapframe *tf;
122 	int sig;
123 	sigset_t *mask;
124 {
125 	struct proc *p = curproc;
126 	struct linux_rt_sigframe *sfp, sigframe;
127 	int onstack;
128 	int fsize, rndfsize;
129 	extern char linux_rt_sigcode[], linux_rt_esigcode[];
130 
131 	/* Do we need to jump onto the signal stack? */
132 	onstack = (p->p_sigctx.ps_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
133 		  (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
134 
135 	/* Allocate space for the signal handler context.  */
136 	fsize = sizeof(struct linux_rt_sigframe);
137 	rndfsize = ((fsize + 15) / 16) * 16;
138 
139 	if (onstack)
140 		sfp = (struct linux_rt_sigframe *)
141 					((caddr_t)p->p_sigctx.ps_sigstk.ss_sp +
142 						p->p_sigctx.ps_sigstk.ss_size);
143 	else
144 		sfp = (struct linux_rt_sigframe *)(alpha_pal_rdusp());
145 	sfp = (struct linux_rt_sigframe *)((caddr_t)sfp - rndfsize);
146 
147 #ifdef DEBUG
148 	if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
149 		printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
150 		    sig, &onstack, sfp);
151 #endif /* DEBUG */
152 
153 	/*
154 	 * Build the signal context to be used by sigreturn.
155 	 */
156 	bzero(&sigframe.uc, sizeof(struct linux_ucontext));
157 	sigframe.uc.uc_mcontext.sc_onstack = onstack;
158 
159 	/* Setup potentially partial signal mask in sc_mask. */
160 	/* But get all of it in uc_sigmask */
161 	native_to_linux_old_sigset(&sigframe.uc.uc_mcontext.sc_mask, mask);
162 	native_to_linux_sigset(&sigframe.uc.uc_sigmask, mask);
163 
164 	sigframe.uc.uc_mcontext.sc_pc = tf->tf_regs[FRAME_PC];
165 	sigframe.uc.uc_mcontext.sc_ps = ALPHA_PSL_USERMODE;
166 	frametoreg(tf, (struct reg *)sigframe.uc.uc_mcontext.sc_regs);
167 	sigframe.uc.uc_mcontext.sc_regs[R_SP] = alpha_pal_rdusp();
168 
169 	alpha_enable_fp(p, 1);
170 	sigframe.uc.uc_mcontext.sc_fpcr = alpha_read_fpcr();
171 	sigframe.uc.uc_mcontext.sc_fp_control = alpha_read_fp_c(p);
172 	alpha_pal_wrfen(0);
173 
174 	sigframe.uc.uc_mcontext.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
175 	sigframe.uc.uc_mcontext.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
176 	sigframe.uc.uc_mcontext.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
177 
178 	/*
179 	 * XXX XAX Create bogus siginfo data.  This can't really
180 	 * XXX be fixed until NetBSD has realtime signals.
181 	 * XXX Or we do the emuldata thing.
182 	 * XXX -erh
183 	 */
184 	bzero(&sigframe.info, sizeof(struct linux_siginfo));
185 	sigframe.info.lsi_signo = sig;
186 	sigframe.info.lsi_code = LINUX_SI_USER;
187 	sigframe.info.lsi_pid = p->p_pid;
188 	sigframe.info.lsi_uid = p->p_ucred->cr_uid;	/* Use real uid here? */
189 
190 	if (copyout((caddr_t)&sigframe, (caddr_t)sfp, fsize) != 0) {
191 #ifdef DEBUG
192 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
193 			printf("sendsig(%d): copyout failed on sig %d\n",
194 			    p->p_pid, sig);
195 #endif
196 		/*
197 		 * Process has trashed its stack; give it an illegal
198 		 * instruction to halt it in its tracks.
199 		 */
200 		sigexit(p, SIGILL);
201 		/* NOTREACHED */
202 	}
203 
204 	/* Pass pointers to siginfo and ucontext in the regs */
205 	tf->tf_regs[FRAME_A1] = (unsigned long)&sfp->info;
206 	tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->uc;
207 
208 	/* Address of trampoline code.  End up at this PC after mi_switch */
209 	tf->tf_regs[FRAME_PC] =
210 	    (u_int64_t)(p->p_psstr - (linux_rt_esigcode - linux_rt_sigcode));
211 
212 	/* Adjust the stack */
213 	alpha_pal_wrusp((unsigned long)sfp);
214 
215 	/* Remember that we're now on the signal stack. */
216 	if (onstack)
217 		p->p_sigctx.ps_sigstk.ss_flags |= SS_ONSTACK;
218 }
219 
220 void setup_linux_sigframe(tf, sig, mask)
221 	struct trapframe *tf;
222 	int sig;
223 	sigset_t *mask;
224 {
225 	struct proc *p = curproc;
226 	struct linux_sigframe *sfp, sigframe;
227 	int onstack;
228 	int fsize, rndfsize;
229 	extern char linux_sigcode[], linux_esigcode[];
230 
231 	/* Do we need to jump onto the signal stack? */
232 	onstack = (p->p_sigctx.ps_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
233 		  (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
234 
235 	/* Allocate space for the signal handler context.  */
236 	fsize = sizeof(struct linux_sigframe);
237 	rndfsize = ((fsize + 15) / 16) * 16;
238 
239 	if (onstack)
240 		sfp = (struct linux_sigframe *)
241 					((caddr_t)p->p_sigctx.ps_sigstk.ss_sp +
242 						p->p_sigctx.ps_sigstk.ss_size);
243 	else
244 		sfp = (struct linux_sigframe *)(alpha_pal_rdusp());
245 	sfp = (struct linux_sigframe *)((caddr_t)sfp - rndfsize);
246 
247 #ifdef DEBUG
248 	if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
249 		printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
250 		    sig, &onstack, sfp);
251 #endif /* DEBUG */
252 
253 	/*
254 	 * Build the signal context to be used by sigreturn.
255 	 */
256 	bzero(&sigframe.sf_sc, sizeof(struct linux_ucontext));
257 	sigframe.sf_sc.sc_onstack = onstack;
258 	native_to_linux_old_sigset(&sigframe.sf_sc.sc_mask, mask);
259 	sigframe.sf_sc.sc_pc = tf->tf_regs[FRAME_PC];
260 	sigframe.sf_sc.sc_ps = ALPHA_PSL_USERMODE;
261 	frametoreg(tf, (struct reg *)sigframe.sf_sc.sc_regs);
262 	sigframe.sf_sc.sc_regs[R_SP] = alpha_pal_rdusp();
263 
264 	if (p == fpcurproc) {
265 	    alpha_pal_wrfen(1);
266 	    savefpstate(&p->p_addr->u_pcb.pcb_fp);
267 	    alpha_pal_wrfen(0);
268 	    sigframe.sf_sc.sc_fpcr = p->p_addr->u_pcb.pcb_fp.fpr_cr;
269 	    fpcurproc = NULL;
270 	}
271 	/* XXX ownedfp ? etc...? */
272 
273 	sigframe.sf_sc.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
274 	sigframe.sf_sc.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
275 	sigframe.sf_sc.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
276 
277 	if (copyout((caddr_t)&sigframe, (caddr_t)sfp, fsize) != 0) {
278 #ifdef DEBUG
279 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
280 			printf("sendsig(%d): copyout failed on sig %d\n",
281 			    p->p_pid, sig);
282 #endif
283 		/*
284 		 * Process has trashed its stack; give it an illegal
285 		 * instruction to halt it in its tracks.
286 		 */
287 		sigexit(p, SIGILL);
288 		/* NOTREACHED */
289 	}
290 
291 	/* Pass pointers to sigcontext in the regs */
292 	tf->tf_regs[FRAME_A1] = 0;
293 	tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->sf_sc;
294 
295 	/* Address of trampoline code.  End up at this PC after mi_switch */
296 	tf->tf_regs[FRAME_PC] =
297 	    (u_int64_t)(p->p_psstr - (linux_esigcode - linux_sigcode));
298 
299 	/* Adjust the stack */
300 	alpha_pal_wrusp((unsigned long)sfp);
301 
302 	/* Remember that we're now on the signal stack. */
303 	if (onstack)
304 		p->p_sigctx.ps_sigstk.ss_flags |= SS_ONSTACK;
305 }
306 
307 /*
308  * Send an interrupt to process.
309  *
310  * Stack is set up to allow sigcode stored
311  * in u. to call routine, followed by kcall
312  * to sigreturn routine below.  After sigreturn
313  * resets the signal mask, the stack, and the
314  * frame pointer, it returns to the user
315  * specified pc, psl.
316  */
317 void
318 linux_sendsig(sig, mask, code)
319 	int sig;
320 	sigset_t *mask;
321 	u_long code;
322 {
323 	struct proc *p = curproc;
324 	struct trapframe *tf = p->p_md.md_tf;
325 	sig_t catcher = SIGACTION(p, sig).sa_handler;
326 #ifdef notyet
327 	struct linux_emuldata *edp;
328 
329 	/* Setup the signal frame (and part of the trapframe) */
330 	/*OLD: if (p->p_sigacts->ps_siginfo & sigmask(sig))*/
331 /*	XXX XAX this is broken now.  need someplace to store what
332 	XXX XAX kind of signal handler a signal has.*/
333 #if 0
334 	edp = (struct linux_emuldata *)p->p_emuldata;
335 #else
336 	edp = 0;
337 #endif
338 	if (edp && sigismember(&edp->ps_siginfo, sig))
339 		setup_linux_rt_sigframe(tf, sig, mask);
340 	else
341 #endif /* notyet */
342 		setup_linux_sigframe(tf, sig, mask);
343 
344 	/* Signal handler for trampoline code */
345 	tf->tf_regs[FRAME_T12] = (u_int64_t)catcher;
346 	tf->tf_regs[FRAME_A0] = native_to_linux_signo[sig];
347 
348 	/*
349 	 * Linux has a custom restorer option.  To support it we would
350 	 * need to store an array of restorers and a sigcode block
351 	 * which knew to use it.  Doesn't seem worth the trouble.
352 	 * -erh
353 	 */
354 
355 #ifdef DEBUG
356 	if (sigdebug & SDB_FOLLOW)
357 		printf("sendsig(%d): pc %lx, catcher %lx\n", p->p_pid,
358 		    tf->tf_regs[FRAME_PC], tf->tf_regs[FRAME_A3]);
359 	if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
360 		printf("sendsig(%d): sig %d returns\n", p->p_pid, sig);
361 #endif
362 }
363 
364 /*
365  * System call to cleanup state after a signal
366  * has been taken.  Reset signal mask and
367  * stack state from context left by sendsig (above).
368  * Return to previous pc as specified by context
369  * left by sendsig.
370  * Linux real-time signals use a different sigframe,
371  * but the sigcontext is the same.
372  */
373 
374 int
375 linux_restore_sigcontext(struct proc *p, struct linux_sigcontext context,
376 			 sigset_t *mask)
377 {
378 
379 	/*
380 	 * Linux doesn't (yet) have alternate signal stacks.
381 	 * However, the OSF/1 sigcontext which they use has
382 	 * an onstack member.  This could be needed in the future.
383 	 */
384 	if (context.sc_onstack & LINUX_SA_ONSTACK)
385 	    p->p_sigctx.ps_sigstk.ss_flags |= SS_ONSTACK;
386 	else
387 	    p->p_sigctx.ps_sigstk.ss_flags &= ~SS_ONSTACK;
388 
389 	/* Reset the signal mask */
390 	(void) sigprocmask1(p, SIG_SETMASK, mask, 0);
391 
392 	/*
393 	 * Check for security violations.
394 	 * Linux doesn't allow any changes to the PSL.
395 	 */
396 	if (context.sc_ps != ALPHA_PSL_USERMODE)
397 	    return(EINVAL);
398 
399 	p->p_md.md_tf->tf_regs[FRAME_PC] = context.sc_pc;
400 	p->p_md.md_tf->tf_regs[FRAME_PS] = context.sc_ps;
401 
402 	regtoframe((struct reg *)context.sc_regs, p->p_md.md_tf);
403 	alpha_pal_wrusp(context.sc_regs[R_SP]);
404 
405 	if (p == fpcurproc)
406 	    fpcurproc = NULL;
407 
408 	/* Restore fp regs and fpr_cr */
409 	bcopy((struct fpreg *)context.sc_fpregs, &p->p_addr->u_pcb.pcb_fp,
410 	    sizeof(struct fpreg));
411 	/* XXX sc_ownedfp ? */
412 	/* XXX sc_fp_control ? */
413 
414 #ifdef DEBUG
415 	if (sigdebug & SDB_FOLLOW)
416 		printf("linux_rt_sigreturn(%d): returns\n", p->p_pid);
417 #endif
418 	return (EJUSTRETURN);
419 }
420 
421 int
422 linux_sys_rt_sigreturn(p, v, retval)
423 	struct proc *p;
424 	void *v;
425 	register_t *retval;
426 {
427 	struct linux_sys_rt_sigreturn_args /* {
428 		syscallarg(struct linux_rt_sigframe *) sfp;
429 	} */ *uap = v;
430 	struct linux_rt_sigframe *sfp, sigframe;
431 	sigset_t mask;
432 
433 	/*
434 	 * The trampoline code hands us the context.
435 	 * It is unsafe to keep track of it ourselves, in the event that a
436 	 * program jumps out of a signal handler.
437 	 */
438 
439 	sfp = SCARG(uap, sfp);
440 
441 	if (ALIGN(sfp) != (u_int64_t)sfp)
442 		return(EINVAL);
443 
444 	/*
445 	 * Fetch the frame structure.
446 	 */
447 	if (copyin((caddr_t)sfp, &sigframe,
448 			sizeof(struct linux_rt_sigframe)) != 0)
449 		return (EFAULT);
450 
451 	/* Grab the signal mask */
452 	linux_to_native_sigset(&mask, &sigframe.uc.uc_sigmask);
453 
454 	return(linux_restore_sigcontext(p, sigframe.uc.uc_mcontext, &mask));
455 }
456 
457 
458 int
459 linux_sys_sigreturn(p, v, retval)
460 	struct proc *p;
461 	void *v;
462 	register_t *retval;
463 {
464 	struct linux_sys_sigreturn_args /* {
465 		syscallarg(struct linux_sigframe *) sfp;
466 	} */ *uap = v;
467 	struct linux_sigframe *sfp, frame;
468 	sigset_t mask;
469 
470 	/*
471 	 * The trampoline code hands us the context.
472 	 * It is unsafe to keep track of it ourselves, in the event that a
473 	 * program jumps out of a signal handler.
474 	 */
475 
476 	sfp = SCARG(uap, sfp);
477 	if (ALIGN(sfp) != (u_int64_t)sfp)
478 		return(EINVAL);
479 
480 	/*
481 	 * Fetch the frame structure.
482 	 */
483 	if (copyin((caddr_t)sfp, &frame, sizeof(struct linux_sigframe)) != 0)
484 		return(EFAULT);
485 
486 	/* Grab the signal mask. */
487 	/* XXX use frame.extramask */
488 	linux_old_to_native_sigset(&mask, frame.sf_sc.sc_mask);
489 
490 	return(linux_restore_sigcontext(p, frame.sf_sc, &mask));
491 }
492 
493 /*
494  * We come here in a last attempt to satisfy a Linux ioctl() call
495  */
496 /* XXX XAX update this, add maps, etc... */
497 int
498 linux_machdepioctl(p, v, retval)
499 	struct proc *p;
500 	void *v;
501 	register_t *retval;
502 {
503 	struct linux_sys_ioctl_args /* {
504 		syscallarg(int) fd;
505 		syscallarg(u_long) com;
506 		syscallarg(caddr_t) data;
507 	} */ *uap = v;
508 	struct sys_ioctl_args bia;
509 	u_long com;
510 
511 	SCARG(&bia, fd) = SCARG(uap, fd);
512 	SCARG(&bia, data) = SCARG(uap, data);
513 	com = SCARG(uap, com);
514 
515 	switch (com) {
516 	default:
517 		printf("linux_machdepioctl: invalid ioctl %08lx\n", com);
518 		return EINVAL;
519 	}
520 	SCARG(&bia, com) = com;
521 	return sys_ioctl(p, &bia, retval);
522 }
523 
524 /* XXX XAX fix this */
525 dev_t
526 linux_fakedev(dev, raw)
527 	dev_t dev;
528 	int raw;
529 {
530 	return dev;
531 }
532 
533