xref: /netbsd-src/sys/compat/linux/arch/powerpc/linux_machdep.c (revision 0df165c04d0a9ca1adde9ed2b890344c937954a6)
1 /*	$NetBSD: linux_machdep.c,v 1.35 2007/10/19 12:16:38 ad Exp $ */
2 
3 /*-
4  * Copyright (c) 1995, 2000, 2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Frank van der Linden and Emmanuel Dreyfus.
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 1.35 2007/10/19 12:16:38 ad Exp $");
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/signalvar.h>
45 #include <sys/kernel.h>
46 #include <sys/proc.h>
47 #include <sys/user.h>
48 #include <sys/buf.h>
49 #include <sys/reboot.h>
50 #include <sys/conf.h>
51 #include <sys/exec.h>
52 #include <sys/file.h>
53 #include <sys/callout.h>
54 #include <sys/malloc.h>
55 #include <sys/mbuf.h>
56 #include <sys/msgbuf.h>
57 #include <sys/mount.h>
58 #include <sys/vnode.h>
59 #include <sys/device.h>
60 #include <sys/syscallargs.h>
61 #include <sys/filedesc.h>
62 #include <sys/exec_elf.h>
63 #include <sys/disklabel.h>
64 #include <sys/ioctl.h>
65 #include <miscfs/specfs/specdev.h>
66 
67 #include <compat/linux/common/linux_types.h>
68 #include <compat/linux/common/linux_signal.h>
69 #include <compat/linux/common/linux_util.h>
70 #include <compat/linux/common/linux_ioctl.h>
71 #include <compat/linux/common/linux_hdio.h>
72 #include <compat/linux/common/linux_exec.h>
73 #include <compat/linux/common/linux_machdep.h>
74 
75 #include <compat/linux/linux_syscallargs.h>
76 
77 #include <sys/cpu.h>
78 #include <machine/fpu.h>
79 #include <machine/psl.h>
80 #include <machine/reg.h>
81 #include <machine/vmparam.h>
82 
83 /*
84  * To see whether wscons is configured (for virtual console ioctl calls).
85  */
86 #if defined(_KERNEL_OPT)
87 #include "wsdisplay.h"
88 #endif
89 #if (NWSDISPLAY > 0)
90 #include <dev/wscons/wsconsio.h>
91 #include <dev/wscons/wsdisplay_usl_io.h>
92 #endif
93 
94 /*
95  * Set set up registers on exec.
96  * XXX not used at the moment since in sys/kern/exec_conf, LINUX_COMPAT
97  * entry uses NetBSD's native setregs instead of linux_setregs
98  */
99 void
100 linux_setregs(l, pack, stack)
101 	struct lwp *l;
102 	struct exec_package *pack;
103 	u_long stack;
104 {
105 	setregs(l, pack, stack);
106 }
107 
108 /*
109  * Send an interrupt to process.
110  *
111  * Adapted from arch/powerpc/powerpc/sig_machdep.c:sendsig and
112  * compat/linux/arch/i386/linux_machdep.c:linux_sendsig
113  *
114  * XXX Does not work well yet with RT signals
115  *
116  */
117 
118 void
119 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
120 {
121 	const int sig = ksi->ksi_signo;
122 	struct lwp *l = curlwp;
123 	struct proc *p = l->l_proc;
124 	struct trapframe *tf;
125 	sig_t catcher = SIGACTION(p, sig).sa_handler;
126 	struct linux_sigregs frame;
127 	struct linux_pt_regs linux_regs;
128 	struct linux_sigcontext sc;
129 	register_t fp;
130 	int onstack, error;
131 	int i;
132 
133 	tf = trapframe(l);
134 
135 	/*
136 	 * Do we need to jump onto the signal stack?
137 	 */
138 	onstack =
139 	    (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
140 	    (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
141 
142 	/*
143 	 * Signal stack is broken (see at the end of linux_sigreturn), so we do
144 	 * not use it yet. XXX fix this.
145 	 */
146 	onstack=0;
147 
148 	/*
149 	 * Allocate space for the signal handler context.
150 	 */
151 	if (onstack) {
152 		fp = (register_t)
153 		    ((char *)l->l_sigstk.ss_sp +
154 		    l->l_sigstk.ss_size);
155 	} else {
156 		fp = tf->fixreg[1];
157 	}
158 #ifdef DEBUG_LINUX
159 	printf("fp at start of linux_sendsig = %x\n", fp);
160 #endif
161 	fp -= sizeof(struct linux_sigregs);
162 	fp &= ~0xf;
163 
164 	/*
165 	 * Prepare a sigcontext for later.
166 	 */
167 	memset(&sc, 0, sizeof sc);
168 	sc.lsignal = (int)native_to_linux_signo[sig];
169 	sc.lhandler = (unsigned long)catcher;
170 	native_to_linux_old_extra_sigset(&sc.lmask, &sc._unused[3], mask);
171 	sc.lregs = (struct linux_pt_regs*)fp;
172 
173 	/*
174 	 * Setup the signal stack frame as Linux does it in
175 	 * arch/ppc/kernel/signal.c:setup_frame()
176 	 *
177 	 * Save register context.
178 	 */
179 	for (i = 0; i < 32; i++)
180 		linux_regs.lgpr[i] = tf->fixreg[i];
181 	linux_regs.lnip = tf->srr0;
182 	linux_regs.lmsr = tf->srr1 & PSL_USERSRR1;
183 	linux_regs.lorig_gpr3 = tf->fixreg[3]; /* XXX Is that right? */
184 	linux_regs.lctr = tf->ctr;
185 	linux_regs.llink = tf->lr;
186 	linux_regs.lxer = tf->xer;
187 	linux_regs.lccr = tf->cr;
188 	linux_regs.lmq = 0;  			/* Unused, 601 only */
189 	linux_regs.ltrap = tf->exc;
190 	linux_regs.ldar = tf->dar;
191 	linux_regs.ldsisr = tf->dsisr;
192 	linux_regs.lresult = 0;
193 
194 	memset(&frame, 0, sizeof(frame));
195 	memcpy(&frame.lgp_regs, &linux_regs, sizeof(linux_regs));
196 
197 	save_fpu_lwp(curlwp, FPU_SAVE);
198 	memcpy(&frame.lfp_regs, curpcb->pcb_fpu.fpreg, sizeof(frame.lfp_regs));
199 
200 	/*
201 	 * Copy Linux's signal trampoline on the user stack It should not
202 	 * be used, but Linux binaries might expect it to be there.
203 	 */
204 	frame.ltramp[0] = 0x38997777; /* li r0, 0x7777 */
205 	frame.ltramp[1] = 0x44000002; /* sc */
206 
207 	/*
208 	 * Move it to the user stack
209 	 * There is a little trick here, about the LINUX_ABIGAP: the
210 	 * linux_sigreg structure has a 56 int gap to support rs6000/xcoff
211 	 * binaries. But the Linux kernel seems to do without it, and it
212 	 * just skip it when building the stack frame. Hence the LINUX_ABIGAP.
213 	 */
214 	sendsig_reset(l, sig);
215 	mutex_exit(&p->p_smutex);
216 	error = copyout(&frame, (void *)fp, sizeof (frame) - LINUX_ABIGAP);
217 
218 	if (error != 0) {
219 		/*
220 		 * Process has trashed its stack; give it an illegal
221 		 * instruction to halt it in its tracks.
222 		 */
223 		mutex_enter(&p->p_smutex);
224 		sigexit(l, SIGILL);
225 		/* NOTREACHED */
226 	}
227 
228 	/*
229 	 * Add a sigcontext on the stack
230 	 */
231 	fp -= sizeof(struct linux_sigcontext);
232 	error = copyout(&sc, (void *)fp, sizeof (struct linux_sigcontext));
233 	mutex_enter(&p->p_smutex);
234 
235 	if (error != 0) {
236 		/*
237 		 * Process has trashed its stack; give it an illegal
238 		 * instruction to halt it in its tracks.
239 		 */
240 		sigexit(l, SIGILL);
241 		/* NOTREACHED */
242 	}
243 
244 	/*
245 	 * Set the registers according to how the Linux process expects them.
246 	 * "Mind the gap" Linux expects a gap here.
247 	 */
248 	tf->fixreg[1] = fp - LINUX__SIGNAL_FRAMESIZE;
249 	tf->lr = (int)catcher;
250 	tf->fixreg[3] = (int)native_to_linux_signo[sig];
251 	tf->fixreg[4] = fp;
252 	tf->srr0 = (int)p->p_sigctx.ps_sigcode;
253 
254 #ifdef DEBUG_LINUX
255 	printf("fp at end of linux_sendsig = %x\n", fp);
256 #endif
257 	/*
258 	 * Remember that we're now on the signal stack.
259 	 */
260 	if (onstack)
261 		l->l_sigstk.ss_flags |= SS_ONSTACK;
262 #ifdef DEBUG_LINUX
263 	printf("linux_sendsig: exitting. fp=0x%lx\n",(long)fp);
264 #endif
265 }
266 
267 /*
268  * System call to cleanup state after a signal
269  * has been taken.  Reset signal mask and
270  * stack state from context left by sendsig (above).
271  * Return to previous pc and psl as specified by
272  * context left by sendsig. Check carefully to
273  * make sure that the user has not modified the
274  * psl to gain improper privileges or to cause
275  * a machine fault.
276  *
277  * XXX not tested
278  */
279 int
280 linux_sys_rt_sigreturn(l, v, retval)
281 	struct lwp *l;
282 	void *v;
283 	register_t *retval;
284 {
285 	struct linux_sys_rt_sigreturn_args /* {
286 		syscallarg(struct linux_rt_sigframe *) sfp;
287 	} */ *uap = v;
288 	struct proc *p = l->l_proc;
289 	struct linux_rt_sigframe *scp, sigframe;
290 	struct linux_sigregs sregs;
291 	struct linux_pt_regs *lregs;
292 	struct trapframe *tf;
293 	sigset_t mask;
294 	int i;
295 
296 	/*
297 	 * The trampoline code hands us the context.
298 	 * It is unsafe to keep track of it ourselves, in the event that a
299 	 * program jumps out of a signal handler.
300 	 */
301 	scp = SCARG(uap, sfp);
302 
303 	/*
304 	 * Get the context from user stack
305 	 */
306 	if (copyin((void *)scp, &sigframe, sizeof(*scp)))
307 		return (EFAULT);
308 
309 	/*
310 	 *  Restore register context.
311 	 */
312 	if (copyin((void *)sigframe.luc.luc_context.lregs,
313 		   &sregs, sizeof(sregs)))
314 		return (EFAULT);
315 	lregs = (struct linux_pt_regs *)&sregs.lgp_regs;
316 
317 	tf = trapframe(l);
318 #ifdef DEBUG_LINUX
319 	    (unsigned long)tf, (unsigned long)scp);
320 #endif
321 
322 	if (!PSL_USEROK_P(lregs->lmsr))
323 		return (EINVAL);
324 
325 	for (i = 0; i < 32; i++)
326 		tf->fixreg[i] = lregs->lgpr[i];
327 	tf->lr = lregs->llink;
328 	tf->cr = lregs->lccr;
329 	tf->xer = lregs->lxer;
330 	tf->ctr = lregs->lctr;
331 	tf->srr0 = lregs->lnip;
332 	tf->srr1 = lregs->lmsr;
333 
334 	/*
335 	 * Make sure the fpu state is discarded
336 	 */
337 	save_fpu_lwp(curlwp, FPU_DISCARD);
338 
339 	memcpy(curpcb->pcb_fpu.fpreg, (void *)&sregs.lfp_regs,
340 	       sizeof(curpcb->pcb_fpu.fpreg));
341 
342 	mutex_enter(&p->p_smutex);
343 
344 	/*
345 	 * Restore signal stack.
346 	 *
347 	 * XXX cannot find the onstack information in Linux sig context.
348 	 * Is signal stack really supported on Linux?
349 	 *
350 	 * It seems to be supported in libc6...
351 	 */
352 	/* if (sc.sc_onstack & SS_ONSTACK)
353 		l->l_sigstk.ss_flags |= SS_ONSTACK;
354 	else */
355 		l->l_sigstk.ss_flags &= ~SS_ONSTACK;
356 
357 	/*
358 	 * Grab the signal mask
359 	 */
360 	linux_to_native_sigset(&mask, &sigframe.luc.luc_sigmask);
361 	(void) sigprocmask1(l, SIG_SETMASK, &mask, 0);
362 
363 	mutex_exit(&p->p_smutex);
364 
365 	return (EJUSTRETURN);
366 }
367 
368 
369 /*
370  * The following needs code review for potential security issues
371  */
372 int
373 linux_sys_sigreturn(l, v, retval)
374 	struct lwp *l;
375 	void *v;
376 	register_t *retval;
377 {
378 	struct linux_sys_sigreturn_args /* {
379 		syscallarg(struct linux_sigcontext *) scp;
380 	} */ *uap = v;
381 	struct proc *p = l->l_proc;
382 	struct linux_sigcontext *scp, context;
383 	struct linux_sigregs sregs;
384 	struct linux_pt_regs *lregs;
385 	struct trapframe *tf;
386 	sigset_t mask;
387 	int i;
388 
389 	/*
390 	 * The trampoline code hands us the context.
391 	 * It is unsafe to keep track of it ourselves, in the event that a
392 	 * program jumps out of a signal handler.
393 	 */
394 	scp = SCARG(uap, scp);
395 
396 	/*
397 	 * Get the context from user stack
398 	 */
399 	if (copyin(scp, &context, sizeof(*scp)))
400 		return (EFAULT);
401 
402 	/*
403 	 *  Restore register context.
404 	 */
405 	if (copyin((void *)context.lregs, &sregs, sizeof(sregs)))
406 		return (EFAULT);
407 	lregs = (struct linux_pt_regs *)&sregs.lgp_regs;
408 
409 	tf = trapframe(l);
410 #ifdef DEBUG_LINUX
411 	printf("linux_sys_sigreturn: trapframe=0x%lx scp=0x%lx\n",
412 	    (unsigned long)tf, (unsigned long)scp);
413 #endif
414 
415 	if (!PSL_USEROK_P(lregs->lmsr))
416 		return (EINVAL);
417 
418 	for (i = 0; i < 32; i++)
419 		tf->fixreg[i] = lregs->lgpr[i];
420 	tf->lr = lregs->llink;
421 	tf->cr = lregs->lccr;
422 	tf->xer = lregs->lxer;
423 	tf->ctr = lregs->lctr;
424 	tf->srr0 = lregs->lnip;
425 	tf->srr1 = lregs->lmsr;
426 
427 	/*
428 	 * Make sure the fpu state is discarded
429 	 */
430 	save_fpu_lwp(curlwp, FPU_DISCARD);
431 
432 	memcpy(curpcb->pcb_fpu.fpreg, (void *)&sregs.lfp_regs,
433 	       sizeof(curpcb->pcb_fpu.fpreg));
434 
435 	mutex_enter(&p->p_smutex);
436 
437 	/*
438 	 * Restore signal stack.
439 	 *
440 	 * XXX cannot find the onstack information in Linux sig context.
441 	 * Is signal stack really supported on Linux?
442 	 */
443 #if 0
444 	if (sc.sc_onstack & SS_ONSTACK)
445 		l->l_sigstk.ss_flags |= SS_ONSTACK;
446 	else
447 #endif
448 		l->l_sigstk.ss_flags &= ~SS_ONSTACK;
449 
450 	/* Restore signal mask. */
451 	linux_old_extra_to_native_sigset(&mask, &context.lmask,
452 	    &context._unused[3]);
453 	(void) sigprocmask1(l, SIG_SETMASK, &mask, 0);
454 
455 	mutex_exit(&p->p_smutex);
456 
457 	return (EJUSTRETURN);
458 }
459 
460 
461 #if 0
462 int
463 linux_sys_modify_ldt(p, v, retval)
464 	struct proc *p;
465 	void *v;
466 	register_t *retval;
467 {
468 	/*
469 	 * This syscall is not implemented in Linux/PowerPC: we should not
470 	 * be here
471 	 */
472 #ifdef DEBUG_LINUX
473 	printf("linux_sys_modify_ldt: should not be here.\n");
474 #endif
475   return 0;
476 }
477 #endif
478 
479 /*
480  * major device numbers remapping
481  */
482 dev_t
483 linux_fakedev(dev, raw)
484 	dev_t dev;
485 	int raw;
486 {
487 	/* XXX write me */
488 	return dev;
489 }
490 
491 /*
492  * We come here in a last attempt to satisfy a Linux ioctl() call
493  */
494 int
495 linux_machdepioctl(l, v, retval)
496 	struct lwp *l;
497 	void *v;
498 	register_t *retval;
499 {
500 	struct linux_sys_ioctl_args /* {
501 		syscallarg(int) fd;
502 		syscallarg(u_long) com;
503 		syscallarg(void *) data;
504 	} */ *uap = v;
505 	struct sys_ioctl_args bia;
506 	u_long com;
507 
508 	SCARG(&bia, fd) = SCARG(uap, fd);
509 	SCARG(&bia, data) = SCARG(uap, data);
510 	com = SCARG(uap, com);
511 
512 	switch (com) {
513 	default:
514 		printf("linux_machdepioctl: invalid ioctl %08lx\n", com);
515 		return EINVAL;
516 	}
517 	SCARG(&bia, com) = com;
518 	/* XXX NJWLWP */
519 	return sys_ioctl(curlwp, &bia, retval);
520 }
521 #if 0
522 /*
523  * Set I/O permissions for a process. Just set the maximum level
524  * right away (ignoring the argument), otherwise we would have
525  * to rely on I/O permission maps, which are not implemented.
526  */
527 int
528 linux_sys_iopl(l, v, retval)
529 	struct lwp *l;
530 	void *v;
531 	register_t *retval;
532 {
533 	/*
534 	 * This syscall is not implemented in Linux/PowerPC: we should not be here
535 	 */
536 #ifdef DEBUG_LINUX
537 	printf("linux_sys_iopl: should not be here.\n");
538 #endif
539 	return 0;
540 }
541 #endif
542 
543 /*
544  * See above. If a root process tries to set access to an I/O port,
545  * just let it have the whole range.
546  */
547 int
548 linux_sys_ioperm(l, v, retval)
549 	struct lwp *l;
550 	void *v;
551 	register_t *retval;
552 {
553 	/*
554 	 * This syscall is not implemented in Linux/PowerPC: we should not be here
555 	 */
556 #ifdef DEBUG_LINUX
557 	printf("linux_sys_ioperm: should not be here.\n");
558 #endif
559 	return 0;
560 }
561 
562 /*
563  * wrapper linux_sys_new_uname() -> linux_sys_uname()
564  */
565 int
566 linux_sys_new_uname(l, v, retval)
567 	struct lwp *l;
568 	void *v;
569 	register_t *retval;
570 {
571 	return linux_sys_uname(l, v, retval);
572 }
573 
574 /*
575  * wrapper linux_sys_new_select() -> linux_sys_select()
576  */
577 int
578 linux_sys_new_select(l, v, retval)
579 	struct lwp *l;
580 	void *v;
581 	register_t *retval;
582 {
583 	return linux_sys_select(l, v, retval);
584 }
585 
586 int
587 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
588 {
589 	return 0;
590 }
591