xref: /netbsd-src/sys/compat/linux/arch/alpha/linux_machdep.c (revision b5677b36047b601b9addaaa494a58ceae82c2a6c)
1 /*	$NetBSD: linux_machdep.c,v 1.44 2009/03/18 17:06:48 cegger 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  *
31  * Based on sys/arch/i386/i386/linux_machdep.c:
32  *	linux_machdep.c,v 1.42 1998/09/11 12:50:06 mycroft Exp
33  *	written by Frank van der Linden
34  *
35  */
36 
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.44 2009/03/18 17:06:48 cegger Exp $");
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/signalvar.h>
43 #include <sys/kernel.h>
44 #include <sys/proc.h>
45 #include <sys/user.h>
46 #include <sys/buf.h>
47 #include <sys/reboot.h>
48 #include <sys/conf.h>
49 #include <sys/exec.h>
50 #include <sys/file.h>
51 #include <sys/callout.h>
52 #include <sys/malloc.h>
53 #include <sys/mbuf.h>
54 #include <sys/msgbuf.h>
55 #include <sys/mount.h>
56 #include <sys/vnode.h>
57 #include <sys/device.h>
58 #include <sys/syscallargs.h>
59 #include <sys/filedesc.h>
60 #include <sys/exec_elf.h>
61 #include <sys/ioctl.h>
62 #include <sys/kauth.h>
63 
64 #include <uvm/uvm_extern.h>
65 
66 #include <compat/linux/common/linux_types.h>
67 #include <compat/linux/common/linux_signal.h>
68 #include <compat/linux/common/linux_siginfo.h>
69 #include <compat/linux/common/linux_util.h>
70 #include <compat/linux/common/linux_ioctl.h>
71 #include <compat/linux/common/linux_exec.h>
72 #include <compat/linux/common/linux_machdep.h>
73 #include <compat/linux/common/linux_emuldata.h>
74 
75 #include <compat/linux/linux_syscallargs.h>
76 
77 #include <machine/alpha.h>
78 #include <machine/reg.h>
79 
80 #if defined(_KERNEL_OPT)
81 #include "wsdisplay.h"
82 #endif
83 #if (NWSDISPLAY >0)
84 #include <dev/wscons/wsdisplay_usl_io.h>
85 #endif
86 #ifdef DEBUG
87 #include <machine/sigdebug.h>
88 #endif
89 
90 /*
91  * Deal with some alpha-specific things in the Linux emulation code.
92  */
93 
94 void
95 linux_setregs(struct lwp *l, struct exec_package *epp, u_long stack)
96 {
97 #ifdef DEBUG
98 	struct trapframe *tfp = l->l_md.md_tf;
99 #endif
100 
101 	setregs(l, epp, stack);
102 #ifdef DEBUG
103 	/*
104 	 * Linux has registers set to zero on entry; for DEBUG kernels
105 	 * the alpha setregs() fills registers with 0xbabefacedeadbeef.
106 	 */
107 	memset(tfp->tf_regs, 0, FRAME_SIZE * sizeof tfp->tf_regs[0]);
108 #endif
109 }
110 
111 void
112 setup_linux_rt_sigframe(struct trapframe *tf, int sig, const sigset_t *mask)
113 {
114 	struct lwp *l = curlwp;
115 	struct proc *p = l->l_proc;
116 	struct linux_rt_sigframe *sfp, sigframe;
117 	int onstack, error;
118 	int fsize, rndfsize;
119 	extern char linux_rt_sigcode[], linux_rt_esigcode[];
120 
121 	/* Do we need to jump onto the signal stack? */
122 	onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
123 		  (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
124 
125 	/* Allocate space for the signal handler context.  */
126 	fsize = sizeof(struct linux_rt_sigframe);
127 	rndfsize = ((fsize + 15) / 16) * 16;
128 
129 	if (onstack)
130 		sfp = (struct linux_rt_sigframe *)
131 		    ((char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size);
132 	else
133 		sfp = (struct linux_rt_sigframe *)(alpha_pal_rdusp());
134 	sfp = (struct linux_rt_sigframe *)((char *)sfp - rndfsize);
135 
136 #ifdef DEBUG
137 	if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
138 		printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
139 		    sig, &onstack, sfp);
140 #endif /* DEBUG */
141 
142 	/*
143 	 * Build the signal context to be used by sigreturn.
144 	 */
145 	memset(&sigframe.uc, 0, sizeof(struct linux_ucontext));
146 	sigframe.uc.uc_mcontext.sc_onstack = onstack;
147 
148 	/* Setup potentially partial signal mask in sc_mask. */
149 	/* But get all of it in uc_sigmask */
150 	native_to_linux_old_sigset(&sigframe.uc.uc_mcontext.sc_mask, mask);
151 	native_to_linux_sigset(&sigframe.uc.uc_sigmask, mask);
152 
153 	sigframe.uc.uc_mcontext.sc_pc = tf->tf_regs[FRAME_PC];
154 	sigframe.uc.uc_mcontext.sc_ps = ALPHA_PSL_USERMODE;
155 	frametoreg(tf, (struct reg *)sigframe.uc.uc_mcontext.sc_regs);
156 	sigframe.uc.uc_mcontext.sc_regs[R_SP] = alpha_pal_rdusp();
157 
158 	alpha_enable_fp(l, 1);
159 	sigframe.uc.uc_mcontext.sc_fpcr = alpha_read_fpcr();
160 	sigframe.uc.uc_mcontext.sc_fp_control = alpha_read_fp_c(l);
161 	alpha_pal_wrfen(0);
162 
163 	sigframe.uc.uc_mcontext.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
164 	sigframe.uc.uc_mcontext.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
165 	sigframe.uc.uc_mcontext.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
166 
167 	/*
168 	 * XXX XAX Create bogus siginfo data.  This can't really
169 	 * XXX be fixed until NetBSD has realtime signals.
170 	 * XXX Or we do the emuldata thing.
171 	 * XXX -erh
172 	 */
173 	memset(&sigframe.info, 0, sizeof(struct linux_siginfo));
174 	sigframe.info.lsi_signo = sig;
175 	sigframe.info.lsi_code = LINUX_SI_USER;
176 	sigframe.info.lsi_pid = p->p_pid;
177 	sigframe.info.lsi_uid = kauth_cred_geteuid(l->l_cred);	/* Use real uid here? */
178 
179 	sendsig_reset(l, sig);
180 	mutex_exit(p->p_lock);
181 	error = copyout((void *)&sigframe, (void *)sfp, fsize);
182 	mutex_enter(p->p_lock);
183 
184 	if (error != 0) {
185 #ifdef DEBUG
186 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
187 			printf("sendsig(%d): copyout failed on sig %d\n",
188 			    p->p_pid, sig);
189 #endif
190 		/*
191 		 * Process has trashed its stack; give it an illegal
192 		 * instruction to halt it in its tracks.
193 		 */
194 		sigexit(l, SIGILL);
195 		/* NOTREACHED */
196 	}
197 
198 	/* Pass pointers to siginfo and ucontext in the regs */
199 	tf->tf_regs[FRAME_A1] = (unsigned long)&sfp->info;
200 	tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->uc;
201 
202 	/* Address of trampoline code.  End up at this PC after mi_switch */
203 	tf->tf_regs[FRAME_PC] =
204 	    (u_int64_t)(p->p_psstr - (linux_rt_esigcode - linux_rt_sigcode));
205 
206 	/* Adjust the stack */
207 	alpha_pal_wrusp((unsigned long)sfp);
208 
209 	/* Remember that we're now on the signal stack. */
210 	if (onstack)
211 		l->l_sigstk.ss_flags |= SS_ONSTACK;
212 }
213 
214 void setup_linux_sigframe(tf, sig, mask)
215 	struct trapframe *tf;
216 	int sig;
217 	const sigset_t *mask;
218 {
219 	struct lwp *l = curlwp;
220 	struct proc *p = l->l_proc;
221 	struct linux_sigframe *sfp, sigframe;
222 	int onstack, error;
223 	int fsize, rndfsize;
224 	extern char linux_sigcode[], linux_esigcode[];
225 
226 	/* Do we need to jump onto the signal stack? */
227 	onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
228 		  (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
229 
230 	/* Allocate space for the signal handler context.  */
231 	fsize = sizeof(struct linux_sigframe);
232 	rndfsize = ((fsize + 15) / 16) * 16;
233 
234 	if (onstack)
235 		sfp = (struct linux_sigframe *)
236 		    ((char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size);
237 	else
238 		sfp = (struct linux_sigframe *)(alpha_pal_rdusp());
239 	sfp = (struct linux_sigframe *)((char *)sfp - rndfsize);
240 
241 #ifdef DEBUG
242 	if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
243 		printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
244 		    sig, &onstack, sfp);
245 #endif /* DEBUG */
246 
247 	/*
248 	 * Build the signal context to be used by sigreturn.
249 	 */
250 	memset(&sigframe.sf_sc, 0, sizeof(struct linux_sigcontext));
251 	sigframe.sf_sc.sc_onstack = onstack;
252 	native_to_linux_old_sigset(&sigframe.sf_sc.sc_mask, mask);
253 	sigframe.sf_sc.sc_pc = tf->tf_regs[FRAME_PC];
254 	sigframe.sf_sc.sc_ps = ALPHA_PSL_USERMODE;
255 	frametoreg(tf, (struct reg *)sigframe.sf_sc.sc_regs);
256 	sigframe.sf_sc.sc_regs[R_SP] = alpha_pal_rdusp();
257 
258 	if (l == fpcurlwp) {
259 	    alpha_pal_wrfen(1);
260 	    savefpstate(&l->l_addr->u_pcb.pcb_fp);
261 	    alpha_pal_wrfen(0);
262 	    sigframe.sf_sc.sc_fpcr = l->l_addr->u_pcb.pcb_fp.fpr_cr;
263 	    fpcurlwp = NULL;
264 	}
265 	/* XXX ownedfp ? etc...? */
266 
267 	sigframe.sf_sc.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
268 	sigframe.sf_sc.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
269 	sigframe.sf_sc.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
270 
271 	sendsig_reset(l, sig);
272 	mutex_exit(p->p_lock);
273 	error = copyout((void *)&sigframe, (void *)sfp, fsize);
274 	mutex_enter(p->p_lock);
275 
276 	if (error != 0) {
277 #ifdef DEBUG
278 		if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
279 			printf("sendsig(%d): copyout failed on sig %d\n",
280 			    p->p_pid, sig);
281 #endif
282 		/*
283 		 * Process has trashed its stack; give it an illegal
284 		 * instruction to halt it in its tracks.
285 		 */
286 		sigexit(l, SIGILL);
287 		/* NOTREACHED */
288 	}
289 
290 	/* Pass pointers to sigcontext in the regs */
291 	tf->tf_regs[FRAME_A1] = 0;
292 	tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->sf_sc;
293 
294 	/* Address of trampoline code.  End up at this PC after mi_switch */
295 	tf->tf_regs[FRAME_PC] =
296 	    (u_int64_t)(p->p_psstr - (linux_esigcode - linux_sigcode));
297 
298 	/* Adjust the stack */
299 	alpha_pal_wrusp((unsigned long)sfp);
300 
301 	/* Remember that we're now on the signal stack. */
302 	if (onstack)
303 		l->l_sigstk.ss_flags |= SS_ONSTACK;
304 }
305 
306 /*
307  * Send an interrupt to process.
308  *
309  * Stack is set up to allow sigcode stored
310  * in u. to call routine, followed by kcall
311  * to sigreturn routine below.  After sigreturn
312  * resets the signal mask, the stack, and the
313  * frame pointer, it returns to the user
314  * specified pc, psl.
315  */
316 void
317 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
318 {
319 	struct lwp *l = curlwp;
320 	struct proc *p = l->l_proc;
321 	struct trapframe *tf = l->l_md.md_tf;
322 	const int sig = ksi->ksi_signo;
323 	sig_t catcher = SIGACTION(p, sig).sa_handler;
324 #ifdef notyet
325 	struct linux_emuldata *edp;
326 
327 	/* Setup the signal frame (and part of the trapframe) */
328 	/*OLD: if (p->p_sigacts->ps_siginfo & sigmask(sig))*/
329 /*	XXX XAX this is broken now.  need someplace to store what
330 	XXX XAX kind of signal handler a signal has.*/
331 #if 0
332 	edp = (struct linux_emuldata *)p->p_emuldata;
333 #else
334 	edp = 0;
335 #endif
336 	if (edp && sigismember(&edp->ps_siginfo, sig))
337 		setup_linux_rt_sigframe(tf, sig, mask);
338 	else
339 #endif /* notyet */
340 		setup_linux_sigframe(tf, sig, mask);
341 
342 	/* Signal handler for trampoline code */
343 	tf->tf_regs[FRAME_T12] = (u_int64_t)catcher;
344 	tf->tf_regs[FRAME_A0] = native_to_linux_signo[sig];
345 
346 	/*
347 	 * Linux has a custom restorer option.  To support it we would
348 	 * need to store an array of restorers and a sigcode block
349 	 * which knew to use it.  Doesn't seem worth the trouble.
350 	 * -erh
351 	 */
352 
353 #ifdef DEBUG
354 	if (sigdebug & SDB_FOLLOW)
355 		printf("sendsig(%d): pc %lx, catcher %lx\n", l->l_proc->p_pid,
356 		    tf->tf_regs[FRAME_PC], tf->tf_regs[FRAME_A3]);
357 	if ((sigdebug & SDB_KSTACK) && l->l_proc->p_pid == sigpid)
358 		printf("sendsig(%d): sig %d returns\n", l->l_proc->p_pid, sig);
359 #endif
360 }
361 
362 /*
363  * System call to cleanup state after a signal
364  * has been taken.  Reset signal mask and
365  * stack state from context left by sendsig (above).
366  * Return to previous pc as specified by context
367  * left by sendsig.
368  * Linux real-time signals use a different sigframe,
369  * but the sigcontext is the same.
370  */
371 
372 int
373 linux_restore_sigcontext(struct lwp *l, struct linux_sigcontext context,
374 			 sigset_t *mask)
375 {
376 	struct proc *p = l->l_proc;
377 
378 	/*
379 	 * Linux doesn't (yet) have alternate signal stacks.
380 	 * However, the OSF/1 sigcontext which they use has
381 	 * an onstack member.  This could be needed in the future.
382 	 */
383 	mutex_enter(p->p_lock);
384 	if (context.sc_onstack & LINUX_SA_ONSTACK)
385 	    l->l_sigstk.ss_flags |= SS_ONSTACK;
386 	else
387 	    l->l_sigstk.ss_flags &= ~SS_ONSTACK;
388 
389 	/* Reset the signal mask */
390 	(void) sigprocmask1(l, SIG_SETMASK, mask, 0);
391 	mutex_exit(p->p_lock);
392 
393 	/*
394 	 * Check for security violations.
395 	 * Linux doesn't allow any changes to the PSL.
396 	 */
397 	if (context.sc_ps != ALPHA_PSL_USERMODE)
398 	    return(EINVAL);
399 
400 	l->l_md.md_tf->tf_regs[FRAME_PC] = context.sc_pc;
401 	l->l_md.md_tf->tf_regs[FRAME_PS] = context.sc_ps;
402 
403 	regtoframe((struct reg *)context.sc_regs, l->l_md.md_tf);
404 	alpha_pal_wrusp(context.sc_regs[R_SP]);
405 
406 	if (l == fpcurlwp)
407 	    fpcurlwp = NULL;
408 
409 	/* Restore fp regs and fpr_cr */
410 	memcpy( &l->l_addr->u_pcb.pcb_fp, (struct fpreg *)context.sc_fpregs,
411 	    sizeof(struct fpreg));
412 	/* XXX sc_ownedfp ? */
413 	/* XXX sc_fp_control ? */
414 
415 #ifdef DEBUG
416 	if (sigdebug & SDB_FOLLOW)
417 		printf("linux_rt_sigreturn(%d): returns\n", p->p_pid);
418 #endif
419 	return (EJUSTRETURN);
420 }
421 
422 int
423 linux_sys_rt_sigreturn(struct lwp *l, const struct linux_sys_rt_sigreturn_args *uap, register_t *retval)
424 {
425 	/* {
426 		syscallarg(struct linux_rt_sigframe *) sfp;
427 	} */
428 	struct linux_rt_sigframe *sfp, sigframe;
429 	sigset_t mask;
430 
431 	/*
432 	 * The trampoline code hands us the context.
433 	 * It is unsafe to keep track of it ourselves, in the event that a
434 	 * program jumps out of a signal handler.
435 	 */
436 
437 	sfp = SCARG(uap, sfp);
438 
439 	if (ALIGN(sfp) != (u_int64_t)sfp)
440 		return(EINVAL);
441 
442 	/*
443 	 * Fetch the frame structure.
444 	 */
445 	if (copyin((void *)sfp, &sigframe,
446 			sizeof(struct linux_rt_sigframe)) != 0)
447 		return (EFAULT);
448 
449 	/* Grab the signal mask */
450 	linux_to_native_sigset(&mask, &sigframe.uc.uc_sigmask);
451 
452 	return(linux_restore_sigcontext(l, sigframe.uc.uc_mcontext, &mask));
453 }
454 
455 
456 int
457 linux_sys_sigreturn(struct lwp *l, const struct linux_sys_sigreturn_args *uap, register_t *retval)
458 {
459 	/* {
460 		syscallarg(struct linux_sigframe *) sfp;
461 	} */
462 	struct linux_sigframe *sfp, frame;
463 	sigset_t mask;
464 
465 	/*
466 	 * The trampoline code hands us the context.
467 	 * It is unsafe to keep track of it ourselves, in the event that a
468 	 * program jumps out of a signal handler.
469 	 */
470 
471 	sfp = SCARG(uap, sfp);
472 	if (ALIGN(sfp) != (u_int64_t)sfp)
473 		return(EINVAL);
474 
475 	/*
476 	 * Fetch the frame structure.
477 	 */
478 	if (copyin((void *)sfp, &frame, sizeof(struct linux_sigframe)) != 0)
479 		return(EFAULT);
480 
481 	/* Grab the signal mask. */
482 	/* XXX use frame.extramask */
483 	linux_old_to_native_sigset(&mask, frame.sf_sc.sc_mask);
484 
485 	return(linux_restore_sigcontext(l, frame.sf_sc, &mask));
486 }
487 
488 /*
489  * We come here in a last attempt to satisfy a Linux ioctl() call
490  */
491 /* XXX XAX update this, add maps, etc... */
492 int
493 linux_machdepioctl(struct lwp *l, const struct linux_sys_ioctl_args *uap, register_t *retval)
494 {
495 	/* {
496 		syscallarg(int) fd;
497 		syscallarg(u_long) com;
498 		syscallarg(void *) data;
499 	} */
500 	struct sys_ioctl_args bia;
501 	u_long com;
502 
503 	SCARG(&bia, fd) = SCARG(uap, fd);
504 	SCARG(&bia, data) = SCARG(uap, data);
505 	com = SCARG(uap, com);
506 
507 	switch (com) {
508 	default:
509 		printf("linux_machdepioctl: invalid ioctl %08lx\n", com);
510 		return EINVAL;
511 	}
512 	SCARG(&bia, com) = com;
513 	return sys_ioctl(l, &bia, retval);
514 }
515 
516 /* XXX XAX fix this */
517 dev_t
518 linux_fakedev(dev_t dev, int raw)
519 {
520 	return dev;
521 }
522 
523 int
524 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
525 {
526 	return 0;
527 }
528