xref: /freebsd/sys/powerpc/powerpc/trap.c (revision 7cc42f6d)
1 /*-
2  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
3  * Copyright (C) 1995, 1996 TooLs GmbH.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by TooLs GmbH.
17  * 4. The name of TooLs GmbH may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  *
31  * $NetBSD: trap.c,v 1.58 2002/03/04 04:07:35 dbj Exp $
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/param.h>
38 #include <sys/kdb.h>
39 #include <sys/proc.h>
40 #include <sys/ktr.h>
41 #include <sys/lock.h>
42 #include <sys/mutex.h>
43 #include <sys/ptrace.h>
44 #include <sys/reboot.h>
45 #include <sys/syscall.h>
46 #include <sys/sysent.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/uio.h>
50 #include <sys/signalvar.h>
51 #include <sys/vmmeter.h>
52 
53 #include <security/audit/audit.h>
54 
55 #include <vm/vm.h>
56 #include <vm/pmap.h>
57 #include <vm/vm_extern.h>
58 #include <vm/vm_param.h>
59 #include <vm/vm_kern.h>
60 #include <vm/vm_map.h>
61 #include <vm/vm_page.h>
62 
63 #include <machine/_inttypes.h>
64 #include <machine/altivec.h>
65 #include <machine/cpu.h>
66 #include <machine/db_machdep.h>
67 #include <machine/fpu.h>
68 #include <machine/frame.h>
69 #include <machine/pcb.h>
70 #include <machine/psl.h>
71 #include <machine/slb.h>
72 #include <machine/spr.h>
73 #include <machine/sr.h>
74 #include <machine/trap.h>
75 
76 /* Below matches setjmp.S */
77 #define	FAULTBUF_LR	21
78 #define	FAULTBUF_R1	1
79 #define	FAULTBUF_R2	2
80 #define	FAULTBUF_CR	22
81 #define	FAULTBUF_R14	3
82 
83 #define	MOREARGS(sp)	((caddr_t)((uintptr_t)(sp) + \
84     sizeof(struct callframe) - 3*sizeof(register_t))) /* more args go here */
85 
86 static void	trap_fatal(struct trapframe *frame);
87 static void	printtrap(u_int vector, struct trapframe *frame, int isfatal,
88 		    int user);
89 static bool	trap_pfault(struct trapframe *frame, bool user, int *signo,
90 		    int *ucode);
91 static int	fix_unaligned(struct thread *td, struct trapframe *frame);
92 static int	handle_onfault(struct trapframe *frame);
93 static void	syscall(struct trapframe *frame);
94 
95 #if defined(__powerpc64__) && defined(AIM)
96 static void	normalize_inputs(void);
97 #endif
98 
99 extern vm_offset_t __startkernel;
100 
101 extern int	copy_fault(void);
102 extern int	fusufault(void);
103 
104 #ifdef KDB
105 int db_trap_glue(struct trapframe *);		/* Called from trap_subr.S */
106 #endif
107 
108 struct powerpc_exception {
109 	u_int	vector;
110 	char	*name;
111 };
112 
113 #ifdef KDTRACE_HOOKS
114 #include <sys/dtrace_bsd.h>
115 
116 int (*dtrace_invop_jump_addr)(struct trapframe *);
117 #endif
118 
119 static struct powerpc_exception powerpc_exceptions[] = {
120 	{ EXC_CRIT,	"critical input" },
121 	{ EXC_RST,	"system reset" },
122 	{ EXC_MCHK,	"machine check" },
123 	{ EXC_DSI,	"data storage interrupt" },
124 	{ EXC_DSE,	"data segment exception" },
125 	{ EXC_ISI,	"instruction storage interrupt" },
126 	{ EXC_ISE,	"instruction segment exception" },
127 	{ EXC_EXI,	"external interrupt" },
128 	{ EXC_ALI,	"alignment" },
129 	{ EXC_PGM,	"program" },
130 	{ EXC_HEA,	"hypervisor emulation assistance" },
131 	{ EXC_FPU,	"floating-point unavailable" },
132 	{ EXC_APU,	"auxiliary proc unavailable" },
133 	{ EXC_DECR,	"decrementer" },
134 	{ EXC_FIT,	"fixed-interval timer" },
135 	{ EXC_WDOG,	"watchdog timer" },
136 	{ EXC_SC,	"system call" },
137 	{ EXC_TRC,	"trace" },
138 	{ EXC_FPA,	"floating-point assist" },
139 	{ EXC_DEBUG,	"debug" },
140 	{ EXC_PERF,	"performance monitoring" },
141 	{ EXC_VEC,	"altivec unavailable" },
142 	{ EXC_VSX,	"vsx unavailable" },
143 	{ EXC_FAC,	"facility unavailable" },
144 	{ EXC_ITMISS,	"instruction tlb miss" },
145 	{ EXC_DLMISS,	"data load tlb miss" },
146 	{ EXC_DSMISS,	"data store tlb miss" },
147 	{ EXC_BPT,	"instruction breakpoint" },
148 	{ EXC_SMI,	"system management" },
149 	{ EXC_VECAST_G4,	"altivec assist" },
150 	{ EXC_THRM,	"thermal management" },
151 	{ EXC_RUNMODETRC,	"run mode/trace" },
152 	{ EXC_SOFT_PATCH, "soft patch exception" },
153 	{ EXC_LAST,	NULL }
154 };
155 
156 #define ESR_BITMASK							\
157     "\20"								\
158     "\040b0\037b1\036b2\035b3\034PIL\033PRR\032PTR\031FP"		\
159     "\030ST\027b9\026DLK\025ILK\024b12\023b13\022BO\021PIE"		\
160     "\020b16\017b17\016b18\015b19\014b20\013b21\012b22\011b23"		\
161     "\010SPE\007EPID\006b26\005b27\004b28\003b29\002b30\001b31"
162 #define	MCSR_BITMASK							\
163     "\20"								\
164     "\040MCP\037ICERR\036DCERR\035TLBPERR\034L2MMU_MHIT\033b5\032b6\031b7"	\
165     "\030b8\027b9\026b10\025NMI\024MAV\023MEA\022b14\021IF"		\
166     "\020LD\017ST\016LDG\015b19\014b20\013b21\012b22\011b23"		\
167     "\010b24\007b25\006b26\005b27\004b28\003b29\002TLBSYNC\001BSL2_ERR"
168 #define	MSSSR_BITMASK							\
169     "\20"								\
170     "\040b0\037b1\036b2\035b3\034b4\033b5\032b6\031b7"			\
171     "\030b8\027b9\026b10\025b11\024b12\023L2TAG\022L2DAT\021L3TAG"	\
172     "\020L3DAT\017APE\016DPE\015TEA\014b20\013b21\012b22\011b23"	\
173     "\010b24\007b25\006b26\005b27\004b28\003b29\002b30\001b31"
174 
175 static const char *
176 trapname(u_int vector)
177 {
178 	struct	powerpc_exception *pe;
179 
180 	for (pe = powerpc_exceptions; pe->vector != EXC_LAST; pe++) {
181 		if (pe->vector == vector)
182 			return (pe->name);
183 	}
184 
185 	return ("unknown");
186 }
187 
188 static inline bool
189 frame_is_trap_inst(struct trapframe *frame)
190 {
191 #ifdef AIM
192 	return (frame->exc == EXC_PGM && frame->srr1 & EXC_PGM_TRAP);
193 #else
194 	return ((frame->cpu.booke.esr & ESR_PTR) != 0);
195 #endif
196 }
197 
198 void
199 trap(struct trapframe *frame)
200 {
201 	struct thread	*td;
202 	struct proc	*p;
203 #ifdef KDTRACE_HOOKS
204 	uint32_t inst;
205 #endif
206 	int		sig, type, user;
207 	u_int		ucode;
208 	ksiginfo_t	ksi;
209 	register_t 	addr, fscr;
210 
211 	VM_CNT_INC(v_trap);
212 
213 #ifdef KDB
214 	if (kdb_active) {
215 		kdb_reenter();
216 		return;
217 	}
218 #endif
219 
220 	td = curthread;
221 	p = td->td_proc;
222 
223 	type = ucode = frame->exc;
224 	sig = 0;
225 	user = frame->srr1 & PSL_PR;
226 	addr = 0;
227 
228 	CTR3(KTR_TRAP, "trap: %s type=%s (%s)", td->td_name,
229 	    trapname(type), user ? "user" : "kernel");
230 
231 #ifdef KDTRACE_HOOKS
232 	/*
233 	 * A trap can occur while DTrace executes a probe. Before
234 	 * executing the probe, DTrace blocks re-scheduling and sets
235 	 * a flag in its per-cpu flags to indicate that it doesn't
236 	 * want to fault. On returning from the probe, the no-fault
237 	 * flag is cleared and finally re-scheduling is enabled.
238 	 *
239 	 * If the DTrace kernel module has registered a trap handler,
240 	 * call it and if it returns non-zero, assume that it has
241 	 * handled the trap and modified the trap frame so that this
242 	 * function can return normally.
243 	 */
244 	if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, type) != 0)
245 		return;
246 #endif
247 
248 	if (user) {
249 		td->td_pticks = 0;
250 		td->td_frame = frame;
251 		addr = frame->srr0;
252 		if (td->td_cowgen != p->p_cowgen)
253 			thread_cow_update(td);
254 
255 		/* User Mode Traps */
256 		switch (type) {
257 		case EXC_RUNMODETRC:
258 		case EXC_TRC:
259 			frame->srr1 &= ~PSL_SE;
260 			sig = SIGTRAP;
261 			ucode = TRAP_TRACE;
262 			break;
263 
264 #if defined(__powerpc64__) && defined(AIM)
265 		case EXC_DSE:
266 			addr = frame->dar;
267 			/* FALLTHROUGH */
268 		case EXC_ISE:
269 			/* DSE/ISE are automatically fatal with radix pmap. */
270 			if (radix_mmu ||
271 			    handle_user_slb_spill(&p->p_vmspace->vm_pmap,
272 			    addr) != 0){
273 				sig = SIGSEGV;
274 				ucode = SEGV_MAPERR;
275 			}
276 			break;
277 #endif
278 		case EXC_DSI:
279 			addr = frame->dar;
280 			/* FALLTHROUGH */
281 		case EXC_ISI:
282 			if (trap_pfault(frame, true, &sig, &ucode))
283 				sig = 0;
284 			break;
285 
286 		case EXC_SC:
287 			syscall(frame);
288 			break;
289 
290 		case EXC_FPU:
291 			KASSERT((td->td_pcb->pcb_flags & PCB_FPU) != PCB_FPU,
292 			    ("FPU already enabled for thread"));
293 			enable_fpu(td);
294 			break;
295 
296 		case EXC_VEC:
297 			KASSERT((td->td_pcb->pcb_flags & PCB_VEC) != PCB_VEC,
298 			    ("Altivec already enabled for thread"));
299 			enable_vec(td);
300 			break;
301 
302 		case EXC_VSX:
303 			KASSERT((td->td_pcb->pcb_flags & PCB_VSX) != PCB_VSX,
304 			    ("VSX already enabled for thread"));
305 			if (!(td->td_pcb->pcb_flags & PCB_VEC))
306 				enable_vec(td);
307 			if (td->td_pcb->pcb_flags & PCB_FPU)
308 				save_fpu(td);
309 			td->td_pcb->pcb_flags |= PCB_VSX;
310 			enable_fpu(td);
311 			break;
312 
313 		case EXC_FAC:
314 			fscr = mfspr(SPR_FSCR);
315 			switch (fscr & FSCR_IC_MASK) {
316 			case FSCR_IC_HTM:
317 				CTR0(KTR_TRAP,
318 				    "Hardware Transactional Memory subsystem disabled");
319 				sig = SIGILL;
320 				ucode =	ILL_ILLOPC;
321 				break;
322 			case FSCR_IC_DSCR:
323 				td->td_pcb->pcb_flags |= PCB_CFSCR | PCB_CDSCR;
324 				fscr |= FSCR_DSCR;
325 				mtspr(SPR_DSCR, 0);
326 				break;
327 			case FSCR_IC_EBB:
328 				td->td_pcb->pcb_flags |= PCB_CFSCR;
329 				fscr |= FSCR_EBB;
330 				mtspr(SPR_EBBHR, 0);
331 				mtspr(SPR_EBBRR, 0);
332 				mtspr(SPR_BESCR, 0);
333 				break;
334 			case FSCR_IC_TAR:
335 				td->td_pcb->pcb_flags |= PCB_CFSCR;
336 				fscr |= FSCR_TAR;
337 				mtspr(SPR_TAR, 0);
338 				break;
339 			case FSCR_IC_LM:
340 				td->td_pcb->pcb_flags |= PCB_CFSCR;
341 				fscr |= FSCR_LM;
342 				mtspr(SPR_LMRR, 0);
343 				mtspr(SPR_LMSER, 0);
344 				break;
345 			default:
346 				sig = SIGILL;
347 				ucode =	ILL_ILLOPC;
348 			}
349 			mtspr(SPR_FSCR, fscr & ~FSCR_IC_MASK);
350 			break;
351 		case EXC_HEA:
352 			sig = SIGILL;
353 			ucode =	ILL_ILLOPC;
354 			break;
355 
356 		case EXC_VECAST_E:
357 		case EXC_VECAST_G4:
358 		case EXC_VECAST_G5:
359 			/*
360 			 * We get a VPU assist exception for IEEE mode
361 			 * vector operations on denormalized floats.
362 			 * Emulating this is a giant pain, so for now,
363 			 * just switch off IEEE mode and treat them as
364 			 * zero.
365 			 */
366 
367 			save_vec(td);
368 			td->td_pcb->pcb_vec.vscr |= ALTIVEC_VSCR_NJ;
369 			enable_vec(td);
370 			break;
371 
372 		case EXC_ALI:
373 			if (fix_unaligned(td, frame) != 0) {
374 				sig = SIGBUS;
375 				ucode = BUS_ADRALN;
376 				addr = frame->dar;
377 			}
378 			else
379 				frame->srr0 += 4;
380 			break;
381 
382 		case EXC_DEBUG:	/* Single stepping */
383 			mtspr(SPR_DBSR, mfspr(SPR_DBSR));
384 			frame->srr1 &= ~PSL_DE;
385 			frame->cpu.booke.dbcr0 &= ~(DBCR0_IDM | DBCR0_IC);
386 			sig = SIGTRAP;
387 			ucode = TRAP_TRACE;
388 			break;
389 
390 		case EXC_PGM:
391 			/* Identify the trap reason */
392 			if (frame_is_trap_inst(frame)) {
393 #ifdef KDTRACE_HOOKS
394 				inst = fuword32((const void *)frame->srr0);
395 				if (inst == 0x0FFFDDDD &&
396 				    dtrace_pid_probe_ptr != NULL) {
397 					(*dtrace_pid_probe_ptr)(frame);
398 					break;
399 				}
400 #endif
401  				sig = SIGTRAP;
402 				ucode = TRAP_BRKPT;
403 			} else {
404 				sig = ppc_instr_emulate(frame, td);
405 				if (sig == SIGILL) {
406 					if (frame->srr1 & EXC_PGM_PRIV)
407 						ucode = ILL_PRVOPC;
408 					else if (frame->srr1 & EXC_PGM_ILLEGAL)
409 						ucode = ILL_ILLOPC;
410 				} else if (sig == SIGFPE)
411 					ucode = FPE_FLTINV;	/* Punt for now, invalid operation. */
412 			}
413 			break;
414 
415 		case EXC_MCHK:
416 			sig = cpu_machine_check(td, frame, &ucode);
417 			printtrap(frame->exc, frame, 0, (frame->srr1 & PSL_PR));
418 			break;
419 
420 #if defined(__powerpc64__) && defined(AIM)
421 		case EXC_SOFT_PATCH:
422 			/*
423 			 * Point to the instruction that generated the exception to execute it again,
424 			 * and normalize the register values.
425 			 */
426 			frame->srr0 -= 4;
427 			normalize_inputs();
428 			break;
429 #endif
430 
431 		default:
432 			trap_fatal(frame);
433 		}
434 	} else {
435 		/* Kernel Mode Traps */
436 
437 		KASSERT(cold || td->td_ucred != NULL,
438 		    ("kernel trap doesn't have ucred"));
439 		switch (type) {
440 		case EXC_PGM:
441 #ifdef KDTRACE_HOOKS
442 			if (frame_is_trap_inst(frame)) {
443 				if (*(uint32_t *)frame->srr0 == EXC_DTRACE) {
444 					if (dtrace_invop_jump_addr != NULL) {
445 						dtrace_invop_jump_addr(frame);
446 						return;
447 					}
448 				}
449 			}
450 #endif
451 #ifdef KDB
452 			if (db_trap_glue(frame))
453 				return;
454 #endif
455 			break;
456 #if defined(__powerpc64__) && defined(AIM)
457 		case EXC_DSE:
458 			/* DSE on radix mmu is automatically fatal. */
459 			if (radix_mmu)
460 				break;
461 			if (td->td_pcb->pcb_cpu.aim.usr_vsid != 0 &&
462 			    (frame->dar & SEGMENT_MASK) == USER_ADDR) {
463 				__asm __volatile ("slbmte %0, %1" ::
464 					"r"(td->td_pcb->pcb_cpu.aim.usr_vsid),
465 					"r"(USER_SLB_SLBE));
466 				return;
467 			}
468 			break;
469 #endif
470 		case EXC_DSI:
471 			if (trap_pfault(frame, false, NULL, NULL))
472  				return;
473 			break;
474 		case EXC_MCHK:
475 			if (handle_onfault(frame))
476  				return;
477 			break;
478 		default:
479 			break;
480 		}
481 		trap_fatal(frame);
482 	}
483 
484 	if (sig != 0) {
485 		if (p->p_sysent->sv_transtrap != NULL)
486 			sig = (p->p_sysent->sv_transtrap)(sig, type);
487 		ksiginfo_init_trap(&ksi);
488 		ksi.ksi_signo = sig;
489 		ksi.ksi_code = (int) ucode; /* XXX, not POSIX */
490 		ksi.ksi_addr = (void *)addr;
491 		ksi.ksi_trapno = type;
492 		trapsignal(td, &ksi);
493 	}
494 
495 	userret(td, frame);
496 }
497 
498 static void
499 trap_fatal(struct trapframe *frame)
500 {
501 #ifdef KDB
502 	bool handled;
503 #endif
504 
505 	printtrap(frame->exc, frame, 1, (frame->srr1 & PSL_PR));
506 #ifdef KDB
507 	if (debugger_on_trap) {
508 		kdb_why = KDB_WHY_TRAP;
509 		handled = kdb_trap(frame->exc, 0, frame);
510 		kdb_why = KDB_WHY_UNSET;
511 		if (handled)
512 			return;
513 	}
514 #endif
515 	panic("%s trap", trapname(frame->exc));
516 }
517 
518 static void
519 cpu_printtrap(u_int vector, struct trapframe *frame, int isfatal, int user)
520 {
521 #ifdef AIM
522 	uint16_t ver;
523 
524 	switch (vector) {
525 	case EXC_MCHK:
526 		ver = mfpvr() >> 16;
527 		if (MPC745X_P(ver))
528 			printf("    msssr0         = 0x%b\n",
529 			    (int)mfspr(SPR_MSSSR0), MSSSR_BITMASK);
530 	case EXC_DSE:
531 	case EXC_DSI:
532 	case EXC_DTMISS:
533 		printf("   dsisr           = 0x%lx\n",
534 		    (u_long)frame->cpu.aim.dsisr);
535 		break;
536 	}
537 #elif defined(BOOKE)
538 	vm_paddr_t pa;
539 
540 	switch (vector) {
541 	case EXC_MCHK:
542 		pa = mfspr(SPR_MCARU);
543 		pa = (pa << 32) | (u_register_t)mfspr(SPR_MCAR);
544 		printf("   mcsr            = 0x%b\n",
545 		    (int)mfspr(SPR_MCSR), MCSR_BITMASK);
546 		printf("   mcar            = 0x%jx\n", (uintmax_t)pa);
547 	}
548 	printf("   esr             = 0x%b\n",
549 	    (int)frame->cpu.booke.esr, ESR_BITMASK);
550 #endif
551 }
552 
553 static void
554 printtrap(u_int vector, struct trapframe *frame, int isfatal, int user)
555 {
556 
557 	printf("\n");
558 	printf("%s %s trap:\n", isfatal ? "fatal" : "handled",
559 	    user ? "user" : "kernel");
560 	printf("\n");
561 	printf("   exception       = 0x%x (%s)\n", vector, trapname(vector));
562 	switch (vector) {
563 	case EXC_DSE:
564 	case EXC_DSI:
565 	case EXC_DTMISS:
566 	case EXC_ALI:
567 	case EXC_MCHK:
568 		printf("   virtual address = 0x%" PRIxPTR "\n", frame->dar);
569 		break;
570 	case EXC_ISE:
571 	case EXC_ISI:
572 	case EXC_ITMISS:
573 		printf("   virtual address = 0x%" PRIxPTR "\n", frame->srr0);
574 		break;
575 	}
576 	cpu_printtrap(vector, frame, isfatal, user);
577 	printf("   srr0            = 0x%" PRIxPTR " (0x%" PRIxPTR ")\n",
578 	    frame->srr0, frame->srr0 - (register_t)(__startkernel - KERNBASE));
579 	printf("   srr1            = 0x%lx\n", (u_long)frame->srr1);
580 	printf("   current msr     = 0x%" PRIxPTR "\n", mfmsr());
581 	printf("   lr              = 0x%" PRIxPTR " (0x%" PRIxPTR ")\n",
582 	    frame->lr, frame->lr - (register_t)(__startkernel - KERNBASE));
583 	printf("   frame           = %p\n", frame);
584 	printf("   curthread       = %p\n", curthread);
585 	if (curthread != NULL)
586 		printf("          pid = %d, comm = %s\n",
587 		    curthread->td_proc->p_pid, curthread->td_name);
588 	printf("\n");
589 }
590 
591 /*
592  * Handles a fatal fault when we have onfault state to recover.  Returns
593  * non-zero if there was onfault recovery state available.
594  */
595 static int
596 handle_onfault(struct trapframe *frame)
597 {
598 	struct		thread *td;
599 	jmp_buf		*fb;
600 
601 	td = curthread;
602 #if defined(__powerpc64__) || defined(BOOKE)
603 	uintptr_t dispatch = (uintptr_t)td->td_pcb->pcb_onfault;
604 
605 	if (dispatch == 0)
606 		return (0);
607 	/* Short-circuit radix and Book-E paths. */
608 	switch (dispatch) {
609 		case COPYFAULT:
610 			frame->srr0 = (uintptr_t)copy_fault;
611 			return (1);
612 		case FUSUFAULT:
613 			frame->srr0 = (uintptr_t)fusufault;
614 			return (1);
615 		default:
616 			break;
617 	}
618 #endif
619 	fb = td->td_pcb->pcb_onfault;
620 	if (fb != NULL) {
621 		frame->srr0 = (*fb)->_jb[FAULTBUF_LR];
622 		frame->fixreg[1] = (*fb)->_jb[FAULTBUF_R1];
623 		frame->fixreg[2] = (*fb)->_jb[FAULTBUF_R2];
624 		frame->fixreg[3] = 1;
625 		frame->cr = (*fb)->_jb[FAULTBUF_CR];
626 		bcopy(&(*fb)->_jb[FAULTBUF_R14], &frame->fixreg[14],
627 		    18 * sizeof(register_t));
628 		td->td_pcb->pcb_onfault = NULL; /* Returns twice, not thrice */
629 		return (1);
630 	}
631 	return (0);
632 }
633 
634 int
635 cpu_fetch_syscall_args(struct thread *td)
636 {
637 	struct proc *p;
638 	struct trapframe *frame;
639 	struct syscall_args *sa;
640 	caddr_t	params;
641 	size_t argsz;
642 	int error, n, narg, i;
643 
644 	p = td->td_proc;
645 	frame = td->td_frame;
646 	sa = &td->td_sa;
647 
648 	sa->code = frame->fixreg[0];
649 	params = (caddr_t)(frame->fixreg + FIRSTARG);
650 	n = NARGREG;
651 
652 	if (sa->code == SYS_syscall) {
653 		/*
654 		 * code is first argument,
655 		 * followed by actual args.
656 		 */
657 		sa->code = *(register_t *) params;
658 		params += sizeof(register_t);
659 		n -= 1;
660 	} else if (sa->code == SYS___syscall) {
661 		/*
662 		 * Like syscall, but code is a quad,
663 		 * so as to maintain quad alignment
664 		 * for the rest of the args.
665 		 */
666 		if (SV_PROC_FLAG(p, SV_ILP32)) {
667 			params += sizeof(register_t);
668 			sa->code = *(register_t *) params;
669 			params += sizeof(register_t);
670 			n -= 2;
671 		} else {
672 			sa->code = *(register_t *) params;
673 			params += sizeof(register_t);
674 			n -= 1;
675 		}
676 	}
677 
678 	if (sa->code >= p->p_sysent->sv_size)
679 		sa->callp = &p->p_sysent->sv_table[0];
680 	else
681 		sa->callp = &p->p_sysent->sv_table[sa->code];
682 
683 	narg = sa->callp->sy_narg;
684 
685 	if (SV_PROC_FLAG(p, SV_ILP32)) {
686 		argsz = sizeof(uint32_t);
687 
688 		for (i = 0; i < n; i++)
689 			sa->args[i] = ((u_register_t *)(params))[i] &
690 			    0xffffffff;
691 	} else {
692 		argsz = sizeof(uint64_t);
693 
694 		for (i = 0; i < n; i++)
695 			sa->args[i] = ((u_register_t *)(params))[i];
696 	}
697 
698 	if (narg > n)
699 		error = copyin(MOREARGS(frame->fixreg[1]), sa->args + n,
700 			       (narg - n) * argsz);
701 	else
702 		error = 0;
703 
704 #ifdef __powerpc64__
705 	if (SV_PROC_FLAG(p, SV_ILP32) && narg > n) {
706 		/* Expand the size of arguments copied from the stack */
707 
708 		for (i = narg; i >= n; i--)
709 			sa->args[i] = ((uint32_t *)(&sa->args[n]))[i-n];
710 	}
711 #endif
712 
713 	if (error == 0) {
714 		td->td_retval[0] = 0;
715 		td->td_retval[1] = frame->fixreg[FIRSTARG + 1];
716 	}
717 	return (error);
718 }
719 
720 #include "../../kern/subr_syscall.c"
721 
722 void
723 syscall(struct trapframe *frame)
724 {
725 	struct thread *td;
726 
727 	td = curthread;
728 	td->td_frame = frame;
729 
730 #if defined(__powerpc64__) && defined(AIM)
731 	/*
732 	 * Speculatively restore last user SLB segment, which we know is
733 	 * invalid already, since we are likely to do copyin()/copyout().
734 	 */
735 	if (td->td_pcb->pcb_cpu.aim.usr_vsid != 0)
736 		__asm __volatile ("slbmte %0, %1; isync" ::
737 		    "r"(td->td_pcb->pcb_cpu.aim.usr_vsid), "r"(USER_SLB_SLBE));
738 #endif
739 
740 	syscallenter(td);
741 	syscallret(td);
742 }
743 
744 static bool
745 trap_pfault(struct trapframe *frame, bool user, int *signo, int *ucode)
746 {
747 	vm_offset_t	eva;
748 	struct		thread *td;
749 	struct		proc *p;
750 	vm_map_t	map;
751 	vm_prot_t	ftype;
752 	int		rv, is_user;
753 
754 	td = curthread;
755 	p = td->td_proc;
756 	if (frame->exc == EXC_ISI) {
757 		eva = frame->srr0;
758 		ftype = VM_PROT_EXECUTE;
759 		if (frame->srr1 & SRR1_ISI_PFAULT)
760 			ftype |= VM_PROT_READ;
761 	} else {
762 		eva = frame->dar;
763 #ifdef BOOKE
764 		if (frame->cpu.booke.esr & ESR_ST)
765 #else
766 		if (frame->cpu.aim.dsisr & DSISR_STORE)
767 #endif
768 			ftype = VM_PROT_WRITE;
769 		else
770 			ftype = VM_PROT_READ;
771 	}
772 #if defined(__powerpc64__) && defined(AIM)
773 	if (radix_mmu && pmap_nofault(&p->p_vmspace->vm_pmap, eva, ftype) == 0)
774 		return (true);
775 #endif
776 
777 	if (__predict_false((td->td_pflags & TDP_NOFAULTING) == 0)) {
778 		/*
779 		 * If we get a page fault while in a critical section, then
780 		 * it is most likely a fatal kernel page fault.  The kernel
781 		 * is already going to panic trying to get a sleep lock to
782 		 * do the VM lookup, so just consider it a fatal trap so the
783 		 * kernel can print out a useful trap message and even get
784 		 * to the debugger.
785 		 *
786 		 * If we get a page fault while holding a non-sleepable
787 		 * lock, then it is most likely a fatal kernel page fault.
788 		 * If WITNESS is enabled, then it's going to whine about
789 		 * bogus LORs with various VM locks, so just skip to the
790 		 * fatal trap handling directly.
791 		 */
792 		if (td->td_critnest != 0 ||
793 			WITNESS_CHECK(WARN_SLEEPOK | WARN_GIANTOK, NULL,
794 				"Kernel page fault") != 0) {
795 			trap_fatal(frame);
796 			return (false);
797 		}
798 	}
799 	if (user) {
800 		KASSERT(p->p_vmspace != NULL, ("trap_pfault: vmspace  NULL"));
801 		map = &p->p_vmspace->vm_map;
802 	} else {
803 		rv = pmap_decode_kernel_ptr(eva, &is_user, &eva);
804 		if (rv != 0)
805 			return (false);
806 
807 		if (is_user)
808 			map = &p->p_vmspace->vm_map;
809 		else
810 			map = kernel_map;
811 	}
812 
813 	/* Fault in the page. */
814 	rv = vm_fault_trap(map, eva, ftype, VM_FAULT_NORMAL, signo, ucode);
815 	/*
816 	 * XXXDTRACE: add dtrace_doubletrap_func here?
817 	 */
818 
819 	if (rv == KERN_SUCCESS)
820 		return (true);
821 
822 	if (!user && handle_onfault(frame))
823 		return (true);
824 
825 	return (false);
826 }
827 
828 /*
829  * For now, this only deals with the particular unaligned access case
830  * that gcc tends to generate.  Eventually it should handle all of the
831  * possibilities that can happen on a 32-bit PowerPC in big-endian mode.
832  */
833 
834 static int
835 fix_unaligned(struct thread *td, struct trapframe *frame)
836 {
837 	struct thread	*fputhread;
838 #ifdef BOOKE
839 	uint32_t	inst;
840 #endif
841 	int		indicator, reg;
842 	double		*fpr;
843 
844 #ifdef __SPE__
845 	indicator = (frame->cpu.booke.esr & (ESR_ST|ESR_SPE));
846 	if (indicator & ESR_SPE) {
847 		if (copyin((void *)frame->srr0, &inst, sizeof(inst)) != 0)
848 			return (-1);
849 		reg = EXC_ALI_INST_RST(inst);
850 		fpr = (double *)td->td_pcb->pcb_vec.vr[reg];
851 		fputhread = PCPU_GET(vecthread);
852 
853 		/* Juggle the SPE to ensure that we've initialized
854 		 * the registers, and that their current state is in
855 		 * the PCB.
856 		 */
857 		if (fputhread != td) {
858 			if (fputhread)
859 				save_vec(fputhread);
860 			enable_vec(td);
861 		}
862 		save_vec(td);
863 
864 		if (!(indicator & ESR_ST)) {
865 			if (copyin((void *)frame->dar, fpr,
866 			    sizeof(double)) != 0)
867 				return (-1);
868 			frame->fixreg[reg] = td->td_pcb->pcb_vec.vr[reg][1];
869 			enable_vec(td);
870 		} else {
871 			td->td_pcb->pcb_vec.vr[reg][1] = frame->fixreg[reg];
872 			if (copyout(fpr, (void *)frame->dar,
873 			    sizeof(double)) != 0)
874 				return (-1);
875 		}
876 		return (0);
877 	}
878 #else
879 #ifdef BOOKE
880 	indicator = (frame->cpu.booke.esr & ESR_ST) ? EXC_ALI_STFD : EXC_ALI_LFD;
881 #else
882 	indicator = EXC_ALI_OPCODE_INDICATOR(frame->cpu.aim.dsisr);
883 #endif
884 
885 	switch (indicator) {
886 	case EXC_ALI_LFD:
887 	case EXC_ALI_STFD:
888 #ifdef BOOKE
889 		if (copyin((void *)frame->srr0, &inst, sizeof(inst)) != 0)
890 			return (-1);
891 		reg = EXC_ALI_INST_RST(inst);
892 #else
893 		reg = EXC_ALI_RST(frame->cpu.aim.dsisr);
894 #endif
895 		fpr = &td->td_pcb->pcb_fpu.fpr[reg].fpr;
896 		fputhread = PCPU_GET(fputhread);
897 
898 		/* Juggle the FPU to ensure that we've initialized
899 		 * the FPRs, and that their current state is in
900 		 * the PCB.
901 		 */
902 		if (fputhread != td) {
903 			if (fputhread)
904 				save_fpu(fputhread);
905 			enable_fpu(td);
906 		}
907 		save_fpu(td);
908 
909 		if (indicator == EXC_ALI_LFD) {
910 			if (copyin((void *)frame->dar, fpr,
911 			    sizeof(double)) != 0)
912 				return (-1);
913 			enable_fpu(td);
914 		} else {
915 			if (copyout(fpr, (void *)frame->dar,
916 			    sizeof(double)) != 0)
917 				return (-1);
918 		}
919 		return (0);
920 		break;
921 	}
922 #endif
923 
924 	return (-1);
925 }
926 
927 #if defined(__powerpc64__) && defined(AIM)
928 #define MSKNSHL(x, m, n) "(((" #x ") & " #m ") << " #n ")"
929 #define MSKNSHR(x, m, n) "(((" #x ") & " #m ") >> " #n ")"
930 
931 /* xvcpsgndp instruction, built in opcode format.
932  * This can be changed to use mnemonic after a toolchain update.
933  */
934 #define XVCPSGNDP(xt, xa, xb) \
935 	__asm __volatile(".long (" \
936 		MSKNSHL(60, 0x3f, 26) " | " \
937 		MSKNSHL(xt, 0x1f, 21) " | " \
938 		MSKNSHL(xa, 0x1f, 16) " | " \
939 		MSKNSHL(xb, 0x1f, 11) " | " \
940 		MSKNSHL(240, 0xff, 3) " | " \
941 		MSKNSHR(xa,  0x20, 3) " | " \
942 		MSKNSHR(xa,  0x20, 4) " | " \
943 		MSKNSHR(xa,  0x20, 5) ")")
944 
945 /* Macros to normalize 1 or 10 VSX registers */
946 #define NORM(x)	XVCPSGNDP(x, x, x)
947 #define NORM10(x) \
948 	NORM(x ## 0); NORM(x ## 1); NORM(x ## 2); NORM(x ## 3); NORM(x ## 4); \
949 	NORM(x ## 5); NORM(x ## 6); NORM(x ## 7); NORM(x ## 8); NORM(x ## 9)
950 
951 static void
952 normalize_inputs(void)
953 {
954 	unsigned long msr;
955 
956 	/* enable VSX */
957 	msr = mfmsr();
958 	mtmsr(msr | PSL_VSX);
959 
960 	NORM(0);   NORM(1);   NORM(2);   NORM(3);   NORM(4);
961 	NORM(5);   NORM(6);   NORM(7);   NORM(8);   NORM(9);
962 	NORM10(1); NORM10(2); NORM10(3); NORM10(4); NORM10(5);
963 	NORM(60);  NORM(61);  NORM(62);  NORM(63);
964 
965 	/* restore MSR */
966 	mtmsr(msr);
967 }
968 #endif
969 
970 #ifdef KDB
971 int
972 db_trap_glue(struct trapframe *frame)
973 {
974 
975 	if (!(frame->srr1 & PSL_PR)
976 	    && (frame->exc == EXC_TRC || frame->exc == EXC_RUNMODETRC
977 	    	|| frame_is_trap_inst(frame)
978 		|| frame->exc == EXC_BPT
979 		|| frame->exc == EXC_DEBUG
980 		|| frame->exc == EXC_DSI)) {
981 		int type = frame->exc;
982 
983 		/* Ignore DTrace traps. */
984 		if (*(uint32_t *)frame->srr0 == EXC_DTRACE)
985 			return (0);
986 		if (frame_is_trap_inst(frame)) {
987 			type = T_BREAKPOINT;
988 		}
989 		return (kdb_trap(type, 0, frame));
990 	}
991 
992 	return (0);
993 }
994 #endif
995