xref: /freebsd/sys/powerpc/powerpc/exec_machdep.c (revision c1d255d3)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause AND BSD-2-Clause-FreeBSD
3  *
4  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
5  * Copyright (C) 1995, 1996 TooLs GmbH.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *      This product includes software developed by TooLs GmbH.
19  * 4. The name of TooLs GmbH may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
28  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 /*-
34  * Copyright (C) 2001 Benno Rice
35  * All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  *
46  * THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
47  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
48  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
49  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
50  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
51  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
52  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
53  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
54  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
55  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56  *	$NetBSD: machdep.c,v 1.74.2.1 2000/11/01 16:13:48 tv Exp $
57  */
58 
59 #include <sys/cdefs.h>
60 __FBSDID("$FreeBSD$");
61 
62 #include "opt_fpu_emu.h"
63 
64 #include <sys/param.h>
65 #include <sys/proc.h>
66 #include <sys/systm.h>
67 #include <sys/bio.h>
68 #include <sys/buf.h>
69 #include <sys/bus.h>
70 #include <sys/cons.h>
71 #include <sys/cpu.h>
72 #include <sys/exec.h>
73 #include <sys/imgact.h>
74 #include <sys/kernel.h>
75 #include <sys/ktr.h>
76 #include <sys/lock.h>
77 #include <sys/malloc.h>
78 #include <sys/mutex.h>
79 #include <sys/reg.h>
80 #include <sys/signalvar.h>
81 #include <sys/syscallsubr.h>
82 #include <sys/syscall.h>
83 #include <sys/sysent.h>
84 #include <sys/sysproto.h>
85 #include <sys/ucontext.h>
86 #include <sys/uio.h>
87 
88 #include <machine/altivec.h>
89 #include <machine/cpu.h>
90 #include <machine/elf.h>
91 #include <machine/fpu.h>
92 #include <machine/pcb.h>
93 #include <machine/sigframe.h>
94 #include <machine/trap.h>
95 #include <machine/vmparam.h>
96 
97 #include <vm/pmap.h>
98 
99 #ifdef FPU_EMU
100 #include <powerpc/fpu/fpu_extern.h>
101 #endif
102 
103 #ifdef COMPAT_FREEBSD32
104 #include <compat/freebsd32/freebsd32_signal.h>
105 #include <compat/freebsd32/freebsd32_util.h>
106 #include <compat/freebsd32/freebsd32_proto.h>
107 
108 typedef struct __ucontext32 {
109 	sigset_t		uc_sigmask;
110 	mcontext32_t		uc_mcontext;
111 	uint32_t		uc_link;
112 	struct sigaltstack32    uc_stack;
113 	uint32_t		uc_flags;
114 	uint32_t		__spare__[4];
115 } ucontext32_t;
116 
117 struct sigframe32 {
118 	ucontext32_t		sf_uc;
119 	struct siginfo32	sf_si;
120 };
121 
122 static int	grab_mcontext32(struct thread *td, mcontext32_t *, int flags);
123 #endif
124 
125 static int	grab_mcontext(struct thread *, mcontext_t *, int);
126 
127 static void	cleanup_power_extras(struct thread *);
128 
129 #ifdef __powerpc64__
130 extern struct sysentvec elf64_freebsd_sysvec_v2;
131 #endif
132 
133 void
134 sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask)
135 {
136 	struct trapframe *tf;
137 	struct sigacts *psp;
138 	struct sigframe sf;
139 	struct thread *td;
140 	struct proc *p;
141 	#ifdef COMPAT_FREEBSD32
142 	struct siginfo32 siginfo32;
143 	struct sigframe32 sf32;
144 	#endif
145 	size_t sfpsize;
146 	caddr_t sfp, usfp;
147 	register_t sp;
148 	int oonstack, rndfsize;
149 	int sig;
150 	int code;
151 
152 	td = curthread;
153 	p = td->td_proc;
154 	PROC_LOCK_ASSERT(p, MA_OWNED);
155 
156 	psp = p->p_sigacts;
157 	mtx_assert(&psp->ps_mtx, MA_OWNED);
158 	tf = td->td_frame;
159 
160 	/*
161 	 * Fill siginfo structure.
162 	 */
163 	ksi->ksi_info.si_signo = ksi->ksi_signo;
164 	ksi->ksi_info.si_addr =
165 	    (void *)((tf->exc == EXC_DSI || tf->exc == EXC_DSE) ?
166 	    tf->dar : tf->srr0);
167 
168 	#ifdef COMPAT_FREEBSD32
169 	if (SV_PROC_FLAG(p, SV_ILP32)) {
170 		siginfo_to_siginfo32(&ksi->ksi_info, &siginfo32);
171 		sig = siginfo32.si_signo;
172 		code = siginfo32.si_code;
173 		sfp = (caddr_t)&sf32;
174 		sfpsize = sizeof(sf32);
175 		rndfsize = roundup(sizeof(sf32), 16);
176 		sp = (uint32_t)tf->fixreg[1];
177 		oonstack = sigonstack(sp);
178 
179 		/*
180 		 * Save user context
181 		 */
182 
183 		memset(&sf32, 0, sizeof(sf32));
184 		grab_mcontext32(td, &sf32.sf_uc.uc_mcontext, 0);
185 
186 		sf32.sf_uc.uc_sigmask = *mask;
187 		sf32.sf_uc.uc_stack.ss_sp = (uintptr_t)td->td_sigstk.ss_sp;
188 		sf32.sf_uc.uc_stack.ss_size = (uint32_t)td->td_sigstk.ss_size;
189 		sf32.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
190 		    ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
191 
192 		sf32.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
193 	} else {
194 	#endif
195 		sig = ksi->ksi_signo;
196 		code = ksi->ksi_code;
197 		sfp = (caddr_t)&sf;
198 		sfpsize = sizeof(sf);
199 		#ifdef __powerpc64__
200 		/*
201 		 * 64-bit PPC defines a 288 byte scratch region
202 		 * below the stack.
203 		 */
204 		rndfsize = 288 + roundup(sizeof(sf), 48);
205 		#else
206 		rndfsize = roundup(sizeof(sf), 16);
207 		#endif
208 		sp = tf->fixreg[1];
209 		oonstack = sigonstack(sp);
210 
211 		/*
212 		 * Save user context
213 		 */
214 
215 		memset(&sf, 0, sizeof(sf));
216 		grab_mcontext(td, &sf.sf_uc.uc_mcontext, 0);
217 
218 		sf.sf_uc.uc_sigmask = *mask;
219 		sf.sf_uc.uc_stack = td->td_sigstk;
220 		sf.sf_uc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK)
221 		    ? ((oonstack) ? SS_ONSTACK : 0) : SS_DISABLE;
222 
223 		sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0;
224 	#ifdef COMPAT_FREEBSD32
225 	}
226 	#endif
227 
228 	CTR4(KTR_SIG, "sendsig: td=%p (%s) catcher=%p sig=%d", td, p->p_comm,
229 	     catcher, sig);
230 
231 	/*
232 	 * Allocate and validate space for the signal handler context.
233 	 */
234 	if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack &&
235 	    SIGISMEMBER(psp->ps_sigonstack, sig)) {
236 		usfp = (void *)(((uintptr_t)td->td_sigstk.ss_sp +
237 		   td->td_sigstk.ss_size - rndfsize) & ~0xFul);
238 	} else {
239 		usfp = (void *)((sp - rndfsize) & ~0xFul);
240 	}
241 
242 	/*
243 	 * Set Floating Point facility to "Ignore Exceptions Mode" so signal
244 	 * handler can run.
245 	 */
246 	if (td->td_pcb->pcb_flags & PCB_FPU)
247 		tf->srr1 = tf->srr1 & ~(PSL_FE0 | PSL_FE1);
248 
249 	/*
250 	 * Set up the registers to return to sigcode.
251 	 *
252 	 *   r1/sp - sigframe ptr
253 	 *   lr    - sig function, dispatched to by blrl in trampoline
254 	 *   r3    - sig number
255 	 *   r4    - SIGINFO ? &siginfo : exception code
256 	 *   r5    - user context
257 	 *   srr0  - trampoline function addr
258 	 */
259 	tf->lr = (register_t)catcher;
260 	tf->fixreg[1] = (register_t)usfp;
261 	tf->fixreg[FIRSTARG] = sig;
262 	#ifdef COMPAT_FREEBSD32
263 	tf->fixreg[FIRSTARG+2] = (register_t)usfp +
264 	    ((SV_PROC_FLAG(p, SV_ILP32)) ?
265 	    offsetof(struct sigframe32, sf_uc) :
266 	    offsetof(struct sigframe, sf_uc));
267 	#else
268 	tf->fixreg[FIRSTARG+2] = (register_t)usfp +
269 	    offsetof(struct sigframe, sf_uc);
270 	#endif
271 	if (SIGISMEMBER(psp->ps_siginfo, sig)) {
272 		/*
273 		 * Signal handler installed with SA_SIGINFO.
274 		 */
275 		#ifdef COMPAT_FREEBSD32
276 		if (SV_PROC_FLAG(p, SV_ILP32)) {
277 			sf32.sf_si = siginfo32;
278 			tf->fixreg[FIRSTARG+1] = (register_t)usfp +
279 			    offsetof(struct sigframe32, sf_si);
280 			sf32.sf_si = siginfo32;
281 		} else  {
282 		#endif
283 			tf->fixreg[FIRSTARG+1] = (register_t)usfp +
284 			    offsetof(struct sigframe, sf_si);
285 			sf.sf_si = ksi->ksi_info;
286 		#ifdef COMPAT_FREEBSD32
287 		}
288 		#endif
289 	} else {
290 		/* Old FreeBSD-style arguments. */
291 		tf->fixreg[FIRSTARG+1] = code;
292 		tf->fixreg[FIRSTARG+3] = (tf->exc == EXC_DSI) ?
293 		    tf->dar : tf->srr0;
294 	}
295 	mtx_unlock(&psp->ps_mtx);
296 	PROC_UNLOCK(p);
297 
298 	tf->srr0 = (register_t)p->p_sysent->sv_sigcode_base;
299 
300 	/*
301 	 * copy the frame out to userland.
302 	 */
303 	if (copyout(sfp, usfp, sfpsize) != 0) {
304 		/*
305 		 * Process has trashed its stack. Kill it.
306 		 */
307 		CTR2(KTR_SIG, "sendsig: sigexit td=%p sfp=%p", td, sfp);
308 		PROC_LOCK(p);
309 		sigexit(td, SIGILL);
310 	}
311 
312 	CTR3(KTR_SIG, "sendsig: return td=%p pc=%#x sp=%#x", td,
313 	     tf->srr0, tf->fixreg[1]);
314 
315 	PROC_LOCK(p);
316 	mtx_lock(&psp->ps_mtx);
317 }
318 
319 int
320 sys_sigreturn(struct thread *td, struct sigreturn_args *uap)
321 {
322 	ucontext_t uc;
323 	int error;
324 
325 	CTR2(KTR_SIG, "sigreturn: td=%p ucp=%p", td, uap->sigcntxp);
326 
327 	if (copyin(uap->sigcntxp, &uc, sizeof(uc)) != 0) {
328 		CTR1(KTR_SIG, "sigreturn: efault td=%p", td);
329 		return (EFAULT);
330 	}
331 
332 	error = set_mcontext(td, &uc.uc_mcontext);
333 	if (error != 0)
334 		return (error);
335 
336 	/*
337 	 * Save FPU state if needed. User may have changed it on
338 	 * signal handler
339 	 */
340 	if (uc.uc_mcontext.mc_srr1 & PSL_FP)
341 		save_fpu(td);
342 
343 	kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0);
344 
345 	CTR3(KTR_SIG, "sigreturn: return td=%p pc=%#x sp=%#x",
346 	     td, uc.uc_mcontext.mc_srr0, uc.uc_mcontext.mc_gpr[1]);
347 
348 	return (EJUSTRETURN);
349 }
350 
351 #ifdef COMPAT_FREEBSD4
352 int
353 freebsd4_sigreturn(struct thread *td, struct freebsd4_sigreturn_args *uap)
354 {
355 
356 	return sys_sigreturn(td, (struct sigreturn_args *)uap);
357 }
358 #endif
359 
360 /*
361  * Construct a PCB from a trapframe. This is called from kdb_trap() where
362  * we want to start a backtrace from the function that caused us to enter
363  * the debugger. We have the context in the trapframe, but base the trace
364  * on the PCB. The PCB doesn't have to be perfect, as long as it contains
365  * enough for a backtrace.
366  */
367 void
368 makectx(struct trapframe *tf, struct pcb *pcb)
369 {
370 
371 	pcb->pcb_lr = tf->srr0;
372 	pcb->pcb_sp = tf->fixreg[1];
373 }
374 
375 /*
376  * get_mcontext/sendsig helper routine that doesn't touch the
377  * proc lock
378  */
379 static int
380 grab_mcontext(struct thread *td, mcontext_t *mcp, int flags)
381 {
382 	struct pcb *pcb;
383 	int i;
384 
385 	pcb = td->td_pcb;
386 
387 	memset(mcp, 0, sizeof(mcontext_t));
388 
389 	mcp->mc_vers = _MC_VERSION;
390 	mcp->mc_flags = 0;
391 	memcpy(&mcp->mc_frame, td->td_frame, sizeof(struct trapframe));
392 	if (flags & GET_MC_CLEAR_RET) {
393 		mcp->mc_gpr[3] = 0;
394 		mcp->mc_gpr[4] = 0;
395 	}
396 
397 	/*
398 	 * This assumes that floating-point context is *not* lazy,
399 	 * so if the thread has used FP there would have been a
400 	 * FP-unavailable exception that would have set things up
401 	 * correctly.
402 	 */
403 	if (pcb->pcb_flags & PCB_FPREGS) {
404 		if (pcb->pcb_flags & PCB_FPU) {
405 			KASSERT(td == curthread,
406 				("get_mcontext: fp save not curthread"));
407 			critical_enter();
408 			save_fpu(td);
409 			critical_exit();
410 		}
411 		mcp->mc_flags |= _MC_FP_VALID;
412 		memcpy(&mcp->mc_fpscr, &pcb->pcb_fpu.fpscr, sizeof(double));
413 		for (i = 0; i < 32; i++)
414 			memcpy(&mcp->mc_fpreg[i], &pcb->pcb_fpu.fpr[i].fpr,
415 			    sizeof(double));
416 	}
417 
418 	if (pcb->pcb_flags & PCB_VSX) {
419 		for (i = 0; i < 32; i++)
420 			memcpy(&mcp->mc_vsxfpreg[i],
421 			    &pcb->pcb_fpu.fpr[i].vsr[2], sizeof(double));
422 	}
423 
424 	/*
425 	 * Repeat for Altivec context
426 	 */
427 
428 	if (pcb->pcb_flags & PCB_VEC) {
429 		KASSERT(td == curthread,
430 			("get_mcontext: fp save not curthread"));
431 		critical_enter();
432 		save_vec(td);
433 		critical_exit();
434 		mcp->mc_flags |= _MC_AV_VALID;
435 		mcp->mc_vscr  = pcb->pcb_vec.vscr;
436 		mcp->mc_vrsave =  pcb->pcb_vec.vrsave;
437 		memcpy(mcp->mc_avec, pcb->pcb_vec.vr, sizeof(mcp->mc_avec));
438 	}
439 
440 	mcp->mc_len = sizeof(*mcp);
441 
442 	return (0);
443 }
444 
445 int
446 get_mcontext(struct thread *td, mcontext_t *mcp, int flags)
447 {
448 	int error;
449 
450 	error = grab_mcontext(td, mcp, flags);
451 	if (error == 0) {
452 		PROC_LOCK(curthread->td_proc);
453 		mcp->mc_onstack = sigonstack(td->td_frame->fixreg[1]);
454 		PROC_UNLOCK(curthread->td_proc);
455 	}
456 
457 	return (error);
458 }
459 
460 int
461 set_mcontext(struct thread *td, mcontext_t *mcp)
462 {
463 	struct pcb *pcb;
464 	struct trapframe *tf;
465 	register_t tls;
466 	int i;
467 
468 	pcb = td->td_pcb;
469 	tf = td->td_frame;
470 
471 	if (mcp->mc_vers != _MC_VERSION || mcp->mc_len != sizeof(*mcp))
472 		return (EINVAL);
473 
474 	/*
475 	 * Don't let the user change privileged MSR bits.
476 	 *
477 	 * psl_userstatic is used here to mask off any bits that can
478 	 * legitimately vary between user contexts (Floating point
479 	 * exception control and any facilities that we are using the
480 	 * "enable on first use" pattern with.)
481 	 *
482 	 * All other bits are required to match psl_userset(32).
483 	 *
484 	 * Remember to update the platform cpu_init code when implementing
485 	 * support for a new conditional facility!
486 	 */
487 	if ((mcp->mc_srr1 & psl_userstatic) != (tf->srr1 & psl_userstatic)) {
488 		return (EINVAL);
489 	}
490 
491 	/* Copy trapframe, preserving TLS pointer across context change */
492 	if (SV_PROC_FLAG(td->td_proc, SV_LP64))
493 		tls = tf->fixreg[13];
494 	else
495 		tls = tf->fixreg[2];
496 	memcpy(tf, mcp->mc_frame, sizeof(mcp->mc_frame));
497 	if (SV_PROC_FLAG(td->td_proc, SV_LP64))
498 		tf->fixreg[13] = tls;
499 	else
500 		tf->fixreg[2] = tls;
501 
502 	/*
503 	 * Force the FPU back off to ensure the new context will not bypass
504 	 * the enable_fpu() setup code accidentally.
505 	 *
506 	 * This prevents an issue where a process that uses floating point
507 	 * inside a signal handler could end up in a state where the MSR
508 	 * did not match pcb_flags.
509 	 *
510 	 * Additionally, ensure VSX is disabled as well, as it is illegal
511 	 * to leave it turned on when FP or VEC are off.
512 	 */
513 	tf->srr1 &= ~(PSL_FP | PSL_VSX);
514 	pcb->pcb_flags &= ~(PCB_FPU | PCB_VSX);
515 
516 	if (mcp->mc_flags & _MC_FP_VALID) {
517 		/* enable_fpu() will happen lazily on a fault */
518 		pcb->pcb_flags |= PCB_FPREGS;
519 		memcpy(&pcb->pcb_fpu.fpscr, &mcp->mc_fpscr, sizeof(double));
520 		bzero(pcb->pcb_fpu.fpr, sizeof(pcb->pcb_fpu.fpr));
521 		for (i = 0; i < 32; i++) {
522 			memcpy(&pcb->pcb_fpu.fpr[i].fpr, &mcp->mc_fpreg[i],
523 			    sizeof(double));
524 			memcpy(&pcb->pcb_fpu.fpr[i].vsr[2],
525 			    &mcp->mc_vsxfpreg[i], sizeof(double));
526 		}
527 	}
528 
529 	if (mcp->mc_flags & _MC_AV_VALID) {
530 		if ((pcb->pcb_flags & PCB_VEC) != PCB_VEC) {
531 			critical_enter();
532 			enable_vec(td);
533 			critical_exit();
534 		}
535 		pcb->pcb_vec.vscr = mcp->mc_vscr;
536 		pcb->pcb_vec.vrsave = mcp->mc_vrsave;
537 		memcpy(pcb->pcb_vec.vr, mcp->mc_avec, sizeof(mcp->mc_avec));
538 	} else {
539 		tf->srr1 &= ~PSL_VEC;
540 		pcb->pcb_flags &= ~PCB_VEC;
541 	}
542 
543 	return (0);
544 }
545 
546 /*
547  * Clean up extra POWER state.  Some per-process registers and states are not
548  * managed by the MSR, so must be cleaned up explicitly on thread exit.
549  *
550  * Currently this includes:
551  * DSCR -- Data stream control register (PowerISA 2.06+)
552  * FSCR -- Facility Status and Control Register (PowerISA 2.07+)
553  */
554 static void
555 cleanup_power_extras(struct thread *td)
556 {
557 	uint32_t pcb_flags;
558 
559 	if (td != curthread)
560 		return;
561 
562 	pcb_flags = td->td_pcb->pcb_flags;
563 	/* Clean up registers not managed by MSR. */
564 	if (pcb_flags & PCB_CFSCR)
565 		mtspr(SPR_FSCR, 0);
566 	if (pcb_flags & PCB_CDSCR)
567 		mtspr(SPR_DSCRP, 0);
568 
569 	if (pcb_flags & PCB_FPU)
570 		cleanup_fpscr();
571 }
572 
573 /*
574  * Set set up registers on exec.
575  */
576 void
577 exec_setregs(struct thread *td, struct image_params *imgp, uintptr_t stack)
578 {
579 	struct trapframe	*tf;
580 	register_t		argc;
581 
582 	tf = trapframe(td);
583 	bzero(tf, sizeof *tf);
584 	#ifdef __powerpc64__
585 	tf->fixreg[1] = -roundup(-stack + 48, 16);
586 	#else
587 	tf->fixreg[1] = -roundup(-stack + 8, 16);
588 	#endif
589 
590 	/*
591 	 * Set up arguments for _start():
592 	 *	_start(argc, argv, envp, obj, cleanup, ps_strings);
593 	 *
594 	 * Notes:
595 	 *	- obj and cleanup are the auxilliary and termination
596 	 *	  vectors.  They are fixed up by ld.elf_so.
597 	 *	- ps_strings is a NetBSD extention, and will be
598 	 * 	  ignored by executables which are strictly
599 	 *	  compliant with the SVR4 ABI.
600 	 */
601 
602 	/* Collect argc from the user stack */
603 	argc = fuword((void *)stack);
604 
605 	tf->fixreg[3] = argc;
606 	tf->fixreg[4] = stack + sizeof(register_t);
607 	tf->fixreg[5] = stack + (2 + argc)*sizeof(register_t);
608 	tf->fixreg[6] = 0;				/* auxillary vector */
609 	tf->fixreg[7] = 0;				/* termination vector */
610 	tf->fixreg[8] = (register_t)imgp->ps_strings;	/* NetBSD extension */
611 
612 	tf->srr0 = imgp->entry_addr;
613 	#ifdef __powerpc64__
614 	tf->fixreg[12] = imgp->entry_addr;
615 	#endif
616 	tf->srr1 = psl_userset | PSL_FE_DFLT;
617 	cleanup_power_extras(td);
618 	td->td_pcb->pcb_flags = 0;
619 }
620 
621 #ifdef COMPAT_FREEBSD32
622 void
623 ppc32_setregs(struct thread *td, struct image_params *imgp, uintptr_t stack)
624 {
625 	struct trapframe	*tf;
626 	uint32_t		argc;
627 
628 	tf = trapframe(td);
629 	bzero(tf, sizeof *tf);
630 	tf->fixreg[1] = -roundup(-stack + 8, 16);
631 
632 	argc = fuword32((void *)stack);
633 
634 	tf->fixreg[3] = argc;
635 	tf->fixreg[4] = stack + sizeof(uint32_t);
636 	tf->fixreg[5] = stack + (2 + argc)*sizeof(uint32_t);
637 	tf->fixreg[6] = 0;				/* auxillary vector */
638 	tf->fixreg[7] = 0;				/* termination vector */
639 	tf->fixreg[8] = (register_t)imgp->ps_strings;	/* NetBSD extension */
640 
641 	tf->srr0 = imgp->entry_addr;
642 	tf->srr1 = psl_userset32 | PSL_FE_DFLT;
643 	cleanup_power_extras(td);
644 	td->td_pcb->pcb_flags = 0;
645 }
646 #endif
647 
648 int
649 fill_regs(struct thread *td, struct reg *regs)
650 {
651 	struct trapframe *tf;
652 
653 	tf = td->td_frame;
654 	memcpy(regs, tf, sizeof(struct reg));
655 
656 	return (0);
657 }
658 
659 int
660 fill_dbregs(struct thread *td, struct dbreg *dbregs)
661 {
662 	/* No debug registers on PowerPC */
663 	return (ENOSYS);
664 }
665 
666 int
667 fill_fpregs(struct thread *td, struct fpreg *fpregs)
668 {
669 	struct pcb *pcb;
670 	int i;
671 
672 	pcb = td->td_pcb;
673 
674 	if ((pcb->pcb_flags & PCB_FPREGS) == 0)
675 		memset(fpregs, 0, sizeof(struct fpreg));
676 	else {
677 		memcpy(&fpregs->fpscr, &pcb->pcb_fpu.fpscr, sizeof(double));
678 		for (i = 0; i < 32; i++)
679 			memcpy(&fpregs->fpreg[i], &pcb->pcb_fpu.fpr[i].fpr,
680 			    sizeof(double));
681 	}
682 
683 	return (0);
684 }
685 
686 int
687 set_regs(struct thread *td, struct reg *regs)
688 {
689 	struct trapframe *tf;
690 
691 	tf = td->td_frame;
692 	memcpy(tf, regs, sizeof(struct reg));
693 
694 	return (0);
695 }
696 
697 int
698 set_dbregs(struct thread *td, struct dbreg *dbregs)
699 {
700 	/* No debug registers on PowerPC */
701 	return (ENOSYS);
702 }
703 
704 int
705 set_fpregs(struct thread *td, struct fpreg *fpregs)
706 {
707 	struct pcb *pcb;
708 	int i;
709 
710 	pcb = td->td_pcb;
711 	pcb->pcb_flags |= PCB_FPREGS;
712 	memcpy(&pcb->pcb_fpu.fpscr, &fpregs->fpscr, sizeof(double));
713 	for (i = 0; i < 32; i++) {
714 		memcpy(&pcb->pcb_fpu.fpr[i].fpr, &fpregs->fpreg[i],
715 		    sizeof(double));
716 	}
717 
718 	return (0);
719 }
720 
721 #ifdef COMPAT_FREEBSD32
722 int
723 set_regs32(struct thread *td, struct reg32 *regs)
724 {
725 	struct trapframe *tf;
726 	int i;
727 
728 	tf = td->td_frame;
729 	for (i = 0; i < 32; i++)
730 		tf->fixreg[i] = regs->fixreg[i];
731 	tf->lr = regs->lr;
732 	tf->cr = regs->cr;
733 	tf->xer = regs->xer;
734 	tf->ctr = regs->ctr;
735 	tf->srr0 = regs->pc;
736 
737 	return (0);
738 }
739 
740 int
741 fill_regs32(struct thread *td, struct reg32 *regs)
742 {
743 	struct trapframe *tf;
744 	int i;
745 
746 	tf = td->td_frame;
747 	for (i = 0; i < 32; i++)
748 		regs->fixreg[i] = tf->fixreg[i];
749 	regs->lr = tf->lr;
750 	regs->cr = tf->cr;
751 	regs->xer = tf->xer;
752 	regs->ctr = tf->ctr;
753 	regs->pc = tf->srr0;
754 
755 	return (0);
756 }
757 
758 static int
759 grab_mcontext32(struct thread *td, mcontext32_t *mcp, int flags)
760 {
761 	mcontext_t mcp64;
762 	int i, error;
763 
764 	error = grab_mcontext(td, &mcp64, flags);
765 	if (error != 0)
766 		return (error);
767 
768 	mcp->mc_vers = mcp64.mc_vers;
769 	mcp->mc_flags = mcp64.mc_flags;
770 	mcp->mc_onstack = mcp64.mc_onstack;
771 	mcp->mc_len = mcp64.mc_len;
772 	memcpy(mcp->mc_avec,mcp64.mc_avec,sizeof(mcp64.mc_avec));
773 	memcpy(mcp->mc_av,mcp64.mc_av,sizeof(mcp64.mc_av));
774 	for (i = 0; i < 42; i++)
775 		mcp->mc_frame[i] = mcp64.mc_frame[i];
776 	memcpy(mcp->mc_fpreg,mcp64.mc_fpreg,sizeof(mcp64.mc_fpreg));
777 	memcpy(mcp->mc_vsxfpreg,mcp64.mc_vsxfpreg,sizeof(mcp64.mc_vsxfpreg));
778 
779 	return (0);
780 }
781 
782 static int
783 get_mcontext32(struct thread *td, mcontext32_t *mcp, int flags)
784 {
785 	int error;
786 
787 	error = grab_mcontext32(td, mcp, flags);
788 	if (error == 0) {
789 		PROC_LOCK(curthread->td_proc);
790 		mcp->mc_onstack = sigonstack(td->td_frame->fixreg[1]);
791 		PROC_UNLOCK(curthread->td_proc);
792 	}
793 
794 	return (error);
795 }
796 
797 static int
798 set_mcontext32(struct thread *td, mcontext32_t *mcp)
799 {
800 	mcontext_t mcp64;
801 	int i, error;
802 
803 	mcp64.mc_vers = mcp->mc_vers;
804 	mcp64.mc_flags = mcp->mc_flags;
805 	mcp64.mc_onstack = mcp->mc_onstack;
806 	mcp64.mc_len = mcp->mc_len;
807 	memcpy(mcp64.mc_avec,mcp->mc_avec,sizeof(mcp64.mc_avec));
808 	memcpy(mcp64.mc_av,mcp->mc_av,sizeof(mcp64.mc_av));
809 	for (i = 0; i < 42; i++)
810 		mcp64.mc_frame[i] = mcp->mc_frame[i];
811 	mcp64.mc_srr1 |= (td->td_frame->srr1 & 0xFFFFFFFF00000000ULL);
812 	memcpy(mcp64.mc_fpreg,mcp->mc_fpreg,sizeof(mcp64.mc_fpreg));
813 	memcpy(mcp64.mc_vsxfpreg,mcp->mc_vsxfpreg,sizeof(mcp64.mc_vsxfpreg));
814 
815 	error = set_mcontext(td, &mcp64);
816 
817 	return (error);
818 }
819 #endif
820 
821 #ifdef COMPAT_FREEBSD32
822 int
823 freebsd32_sigreturn(struct thread *td, struct freebsd32_sigreturn_args *uap)
824 {
825 	ucontext32_t uc;
826 	int error;
827 
828 	CTR2(KTR_SIG, "sigreturn: td=%p ucp=%p", td, uap->sigcntxp);
829 
830 	if (copyin(uap->sigcntxp, &uc, sizeof(uc)) != 0) {
831 		CTR1(KTR_SIG, "sigreturn: efault td=%p", td);
832 		return (EFAULT);
833 	}
834 
835 	error = set_mcontext32(td, &uc.uc_mcontext);
836 	if (error != 0)
837 		return (error);
838 
839 	/*
840 	 * Save FPU state if needed. User may have changed it on
841 	 * signal handler
842 	 */
843 	if (uc.uc_mcontext.mc_srr1 & PSL_FP)
844 		save_fpu(td);
845 
846 	kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0);
847 
848 	CTR3(KTR_SIG, "sigreturn: return td=%p pc=%#x sp=%#x",
849 	     td, uc.uc_mcontext.mc_srr0, uc.uc_mcontext.mc_gpr[1]);
850 
851 	return (EJUSTRETURN);
852 }
853 
854 /*
855  * The first two fields of a ucontext_t are the signal mask and the machine
856  * context.  The next field is uc_link; we want to avoid destroying the link
857  * when copying out contexts.
858  */
859 #define	UC32_COPY_SIZE	offsetof(ucontext32_t, uc_link)
860 
861 int
862 freebsd32_getcontext(struct thread *td, struct freebsd32_getcontext_args *uap)
863 {
864 	ucontext32_t uc;
865 	int ret;
866 
867 	if (uap->ucp == NULL)
868 		ret = EINVAL;
869 	else {
870 		bzero(&uc, sizeof(uc));
871 		get_mcontext32(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
872 		PROC_LOCK(td->td_proc);
873 		uc.uc_sigmask = td->td_sigmask;
874 		PROC_UNLOCK(td->td_proc);
875 		ret = copyout(&uc, uap->ucp, UC32_COPY_SIZE);
876 	}
877 	return (ret);
878 }
879 
880 int
881 freebsd32_setcontext(struct thread *td, struct freebsd32_setcontext_args *uap)
882 {
883 	ucontext32_t uc;
884 	int ret;
885 
886 	if (uap->ucp == NULL)
887 		ret = EINVAL;
888 	else {
889 		ret = copyin(uap->ucp, &uc, UC32_COPY_SIZE);
890 		if (ret == 0) {
891 			ret = set_mcontext32(td, &uc.uc_mcontext);
892 			if (ret == 0) {
893 				kern_sigprocmask(td, SIG_SETMASK,
894 				    &uc.uc_sigmask, NULL, 0);
895 			}
896 		}
897 	}
898 	return (ret == 0 ? EJUSTRETURN : ret);
899 }
900 
901 int
902 freebsd32_swapcontext(struct thread *td, struct freebsd32_swapcontext_args *uap)
903 {
904 	ucontext32_t uc;
905 	int ret;
906 
907 	if (uap->oucp == NULL || uap->ucp == NULL)
908 		ret = EINVAL;
909 	else {
910 		bzero(&uc, sizeof(uc));
911 		get_mcontext32(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
912 		PROC_LOCK(td->td_proc);
913 		uc.uc_sigmask = td->td_sigmask;
914 		PROC_UNLOCK(td->td_proc);
915 		ret = copyout(&uc, uap->oucp, UC32_COPY_SIZE);
916 		if (ret == 0) {
917 			ret = copyin(uap->ucp, &uc, UC32_COPY_SIZE);
918 			if (ret == 0) {
919 				ret = set_mcontext32(td, &uc.uc_mcontext);
920 				if (ret == 0) {
921 					kern_sigprocmask(td, SIG_SETMASK,
922 					    &uc.uc_sigmask, NULL, 0);
923 				}
924 			}
925 		}
926 	}
927 	return (ret == 0 ? EJUSTRETURN : ret);
928 }
929 
930 #endif
931 
932 void
933 cpu_set_syscall_retval(struct thread *td, int error)
934 {
935 	struct proc *p;
936 	struct trapframe *tf;
937 	int fixup;
938 
939 	if (error == EJUSTRETURN)
940 		return;
941 
942 	p = td->td_proc;
943 	tf = td->td_frame;
944 
945 	if (tf->fixreg[0] == SYS___syscall &&
946 	    (SV_PROC_FLAG(p, SV_ILP32))) {
947 		int code = tf->fixreg[FIRSTARG + 1];
948 		fixup = (
949 #if defined(COMPAT_FREEBSD6) && defined(SYS_freebsd6_lseek)
950 		    code != SYS_freebsd6_lseek &&
951 #endif
952 		    code != SYS_lseek) ?  1 : 0;
953 	} else
954 		fixup = 0;
955 
956 	switch (error) {
957 	case 0:
958 		if (fixup) {
959 			/*
960 			 * 64-bit return, 32-bit syscall. Fixup byte order
961 			 */
962 			tf->fixreg[FIRSTARG] = 0;
963 			tf->fixreg[FIRSTARG + 1] = td->td_retval[0];
964 		} else {
965 			tf->fixreg[FIRSTARG] = td->td_retval[0];
966 			tf->fixreg[FIRSTARG + 1] = td->td_retval[1];
967 		}
968 		tf->cr &= ~0x10000000;		/* Unset summary overflow */
969 		break;
970 	case ERESTART:
971 		/*
972 		 * Set user's pc back to redo the system call.
973 		 */
974 		tf->srr0 -= 4;
975 		break;
976 	default:
977 		tf->fixreg[FIRSTARG] = error;
978 		tf->cr |= 0x10000000;		/* Set summary overflow */
979 		break;
980 	}
981 }
982 
983 /*
984  * Threading functions
985  */
986 void
987 cpu_thread_exit(struct thread *td)
988 {
989 	cleanup_power_extras(td);
990 }
991 
992 void
993 cpu_thread_clean(struct thread *td)
994 {
995 }
996 
997 void
998 cpu_thread_alloc(struct thread *td)
999 {
1000 	struct pcb *pcb;
1001 
1002 	pcb = (struct pcb *)((td->td_kstack + td->td_kstack_pages * PAGE_SIZE -
1003 	    sizeof(struct pcb)) & ~0x2fUL);
1004 	td->td_pcb = pcb;
1005 	td->td_frame = (struct trapframe *)pcb - 1;
1006 }
1007 
1008 void
1009 cpu_thread_free(struct thread *td)
1010 {
1011 }
1012 
1013 int
1014 cpu_set_user_tls(struct thread *td, void *tls_base)
1015 {
1016 
1017 	if (SV_PROC_FLAG(td->td_proc, SV_LP64))
1018 		td->td_frame->fixreg[13] = (register_t)tls_base + 0x7010;
1019 	else
1020 		td->td_frame->fixreg[2] = (register_t)tls_base + 0x7008;
1021 	return (0);
1022 }
1023 
1024 void
1025 cpu_copy_thread(struct thread *td, struct thread *td0)
1026 {
1027 	struct pcb *pcb2;
1028 	struct trapframe *tf;
1029 	struct callframe *cf;
1030 
1031 	pcb2 = td->td_pcb;
1032 
1033 	/* Copy the upcall pcb */
1034 	bcopy(td0->td_pcb, pcb2, sizeof(*pcb2));
1035 
1036 	/* Create a stack for the new thread */
1037 	tf = td->td_frame;
1038 	bcopy(td0->td_frame, tf, sizeof(struct trapframe));
1039 	tf->fixreg[FIRSTARG] = 0;
1040 	tf->fixreg[FIRSTARG + 1] = 0;
1041 	tf->cr &= ~0x10000000;
1042 
1043 	/* Set registers for trampoline to user mode. */
1044 	cf = (struct callframe *)tf - 1;
1045 	memset(cf, 0, sizeof(struct callframe));
1046 	cf->cf_func = (register_t)fork_return;
1047 	cf->cf_arg0 = (register_t)td;
1048 	cf->cf_arg1 = (register_t)tf;
1049 
1050 	pcb2->pcb_sp = (register_t)cf;
1051 	#if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1)
1052 	pcb2->pcb_lr = ((register_t *)fork_trampoline)[0];
1053 	pcb2->pcb_toc = ((register_t *)fork_trampoline)[1];
1054 	#else
1055 	pcb2->pcb_lr = (register_t)fork_trampoline;
1056 	pcb2->pcb_context[0] = pcb2->pcb_lr;
1057 	#endif
1058 	pcb2->pcb_cpu.aim.usr_vsid = 0;
1059 #ifdef __SPE__
1060 	pcb2->pcb_vec.vscr = SPEFSCR_DFLT;
1061 #endif
1062 
1063 	/* Setup to release spin count in fork_exit(). */
1064 	td->td_md.md_spinlock_count = 1;
1065 	td->td_md.md_saved_msr = psl_kernset;
1066 }
1067 
1068 void
1069 cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg,
1070     stack_t *stack)
1071 {
1072 	struct trapframe *tf;
1073 	uintptr_t sp;
1074 
1075 	tf = td->td_frame;
1076 	/* align stack and alloc space for frame ptr and saved LR */
1077 	#ifdef __powerpc64__
1078 	sp = ((uintptr_t)stack->ss_sp + stack->ss_size - 48) &
1079 	    ~0x1f;
1080 	#else
1081 	sp = ((uintptr_t)stack->ss_sp + stack->ss_size - 8) &
1082 	    ~0x1f;
1083 	#endif
1084 	bzero(tf, sizeof(struct trapframe));
1085 
1086 	tf->fixreg[1] = (register_t)sp;
1087 	tf->fixreg[3] = (register_t)arg;
1088 	if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
1089 		tf->srr0 = (register_t)entry;
1090 		#ifdef __powerpc64__
1091 		tf->srr1 = psl_userset32 | PSL_FE_DFLT;
1092 		#else
1093 		tf->srr1 = psl_userset | PSL_FE_DFLT;
1094 		#endif
1095 	} else {
1096 	    #ifdef __powerpc64__
1097 		if (td->td_proc->p_sysent == &elf64_freebsd_sysvec_v2) {
1098 			tf->srr0 = (register_t)entry;
1099 			/* ELFv2 ABI requires that the global entry point be in r12. */
1100 			tf->fixreg[12] = (register_t)entry;
1101 		}
1102 		else {
1103 			register_t entry_desc[3];
1104 			(void)copyin((void *)entry, entry_desc, sizeof(entry_desc));
1105 			tf->srr0 = entry_desc[0];
1106 			tf->fixreg[2] = entry_desc[1];
1107 			tf->fixreg[11] = entry_desc[2];
1108 		}
1109 		tf->srr1 = psl_userset | PSL_FE_DFLT;
1110 	    #endif
1111 	}
1112 
1113 	td->td_pcb->pcb_flags = 0;
1114 #ifdef __SPE__
1115 	td->td_pcb->pcb_vec.vscr = SPEFSCR_DFLT;
1116 #endif
1117 
1118 	td->td_retval[0] = (register_t)entry;
1119 	td->td_retval[1] = 0;
1120 }
1121 
1122 static int
1123 emulate_mfspr(int spr, int reg, struct trapframe *frame){
1124 	struct thread *td;
1125 
1126 	td = curthread;
1127 
1128 	if (spr == SPR_DSCR || spr == SPR_DSCRP) {
1129 		if (!(cpu_features2 & PPC_FEATURE2_DSCR))
1130 			return (SIGILL);
1131 		// If DSCR was never set, get the default DSCR
1132 		if ((td->td_pcb->pcb_flags & PCB_CDSCR) == 0)
1133 			td->td_pcb->pcb_dscr = mfspr(SPR_DSCRP);
1134 
1135 		frame->fixreg[reg] = td->td_pcb->pcb_dscr;
1136 		frame->srr0 += 4;
1137 		return (0);
1138 	} else
1139 		return (SIGILL);
1140 }
1141 
1142 static int
1143 emulate_mtspr(int spr, int reg, struct trapframe *frame){
1144 	struct thread *td;
1145 
1146 	td = curthread;
1147 
1148 	if (spr == SPR_DSCR || spr == SPR_DSCRP) {
1149 		if (!(cpu_features2 & PPC_FEATURE2_DSCR))
1150 			return (SIGILL);
1151 		td->td_pcb->pcb_flags |= PCB_CDSCR;
1152 		td->td_pcb->pcb_dscr = frame->fixreg[reg];
1153 		mtspr(SPR_DSCRP, frame->fixreg[reg]);
1154 		frame->srr0 += 4;
1155 		return (0);
1156 	} else
1157 		return (SIGILL);
1158 }
1159 
1160 #define XFX 0xFC0007FF
1161 int
1162 ppc_instr_emulate(struct trapframe *frame, struct thread *td)
1163 {
1164 	struct pcb *pcb;
1165 	uint32_t instr;
1166 	int reg, sig;
1167 	int rs, spr;
1168 
1169 	instr = fuword32((void *)frame->srr0);
1170 	sig = SIGILL;
1171 
1172 	if ((instr & 0xfc1fffff) == 0x7c1f42a6) {	/* mfpvr */
1173 		reg = (instr & ~0xfc1fffff) >> 21;
1174 		frame->fixreg[reg] = mfpvr();
1175 		frame->srr0 += 4;
1176 		return (0);
1177 	} else if ((instr & XFX) == 0x7c0002a6) {	/* mfspr */
1178 		rs = (instr &  0x3e00000) >> 21;
1179 		spr = (instr & 0x1ff800) >> 16;
1180 		return emulate_mfspr(spr, rs, frame);
1181 	} else if ((instr & XFX) == 0x7c0003a6) {	/* mtspr */
1182 		rs = (instr &  0x3e00000) >> 21;
1183 		spr = (instr & 0x1ff800) >> 16;
1184 		return emulate_mtspr(spr, rs, frame);
1185 	} else if ((instr & 0xfc000ffe) == 0x7c0004ac) {	/* various sync */
1186 		powerpc_sync(); /* Do a heavy-weight sync */
1187 		frame->srr0 += 4;
1188 		return (0);
1189 	}
1190 
1191 	pcb = td->td_pcb;
1192 #ifdef FPU_EMU
1193 	if (!(pcb->pcb_flags & PCB_FPREGS)) {
1194 		bzero(&pcb->pcb_fpu, sizeof(pcb->pcb_fpu));
1195 		pcb->pcb_flags |= PCB_FPREGS;
1196 	} else if (pcb->pcb_flags & PCB_FPU)
1197 		save_fpu(td);
1198 	sig = fpu_emulate(frame, &pcb->pcb_fpu);
1199 	if ((sig == 0 || sig == SIGFPE) && pcb->pcb_flags & PCB_FPU)
1200 		enable_fpu(td);
1201 #endif
1202 	if (sig == SIGILL) {
1203 		if (pcb->pcb_lastill != frame->srr0) {
1204 			/* Allow a second chance, in case of cache sync issues. */
1205 			sig = 0;
1206 			pmap_sync_icache(PCPU_GET(curpmap), frame->srr0, 4);
1207 			pcb->pcb_lastill = frame->srr0;
1208 		}
1209 	}
1210 
1211 	return (sig);
1212 }
1213