xref: /freebsd-14.2/sys/powerpc/powerpc/trap.c (revision e0f10213)
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 #include <sys/param.h>
36 #include <sys/kdb.h>
37 #include <sys/proc.h>
38 #include <sys/ktr.h>
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 #include <sys/ptrace.h>
42 #include <sys/reboot.h>
43 #include <sys/syscall.h>
44 #include <sys/sysent.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/uio.h>
48 #include <sys/signalvar.h>
49 #include <sys/vmmeter.h>
50 
51 #include <security/audit/audit.h>
52 
53 #include <vm/vm.h>
54 #include <vm/pmap.h>
55 #include <vm/vm_extern.h>
56 #include <vm/vm_param.h>
57 #include <vm/vm_kern.h>
58 #include <vm/vm_map.h>
59 #include <vm/vm_page.h>
60 
61 #include <machine/_inttypes.h>
62 #include <machine/altivec.h>
63 #include <machine/cpu.h>
64 #include <machine/db_machdep.h>
65 #include <machine/fpu.h>
66 #include <machine/frame.h>
67 #include <machine/pcb.h>
68 #include <machine/psl.h>
69 #include <machine/slb.h>
70 #include <machine/spr.h>
71 #include <machine/sr.h>
72 #include <machine/trap.h>
73 
74 /* Below matches setjmp.S */
75 #define	FAULTBUF_LR	21
76 #define	FAULTBUF_R1	1
77 #define	FAULTBUF_R2	2
78 #define	FAULTBUF_CR	22
79 #define	FAULTBUF_R14	3
80 
81 #define	MOREARGS(sp)	((caddr_t)((uintptr_t)(sp) + \
82     sizeof(struct callframe) - 3*sizeof(register_t))) /* more args go here */
83 
84 static void	trap_fatal(struct trapframe *frame);
85 static void	printtrap(u_int vector, struct trapframe *frame, int isfatal,
86 		    int user);
87 static bool	trap_pfault(struct trapframe *frame, bool user, int *signo,
88 		    int *ucode);
89 static int	fix_unaligned(struct thread *td, struct trapframe *frame);
90 static int	handle_onfault(struct trapframe *frame);
91 static void	syscall(struct trapframe *frame);
92 
93 #if defined(__powerpc64__) && defined(AIM)
94 static void	normalize_inputs(void);
95 #endif
96 
97 extern vm_offset_t __startkernel;
98 
99 extern int	copy_fault(void);
100 extern int	fusufault(void);
101 
102 #ifdef KDB
103 int db_trap_glue(struct trapframe *);		/* Called from trap_subr.S */
104 #endif
105 
106 struct powerpc_exception {
107 	u_int	vector;
108 	char	*name;
109 };
110 
111 #ifdef KDTRACE_HOOKS
112 #include <sys/dtrace_bsd.h>
113 
114 int (*dtrace_invop_jump_addr)(struct trapframe *);
115 #endif
116 
117 static struct powerpc_exception powerpc_exceptions[] = {
118 	{ EXC_CRIT,	"critical input" },
119 	{ EXC_RST,	"system reset" },
120 	{ EXC_MCHK,	"machine check" },
121 	{ EXC_DSI,	"data storage interrupt" },
122 	{ EXC_DSE,	"data segment exception" },
123 	{ EXC_ISI,	"instruction storage interrupt" },
124 	{ EXC_ISE,	"instruction segment exception" },
125 	{ EXC_EXI,	"external interrupt" },
126 	{ EXC_ALI,	"alignment" },
127 	{ EXC_PGM,	"program" },
128 	{ EXC_HEA,	"hypervisor emulation assistance" },
129 	{ EXC_FPU,	"floating-point unavailable" },
130 	{ EXC_APU,	"auxiliary proc unavailable" },
131 	{ EXC_DECR,	"decrementer" },
132 	{ EXC_FIT,	"fixed-interval timer" },
133 	{ EXC_WDOG,	"watchdog timer" },
134 	{ EXC_SC,	"system call" },
135 	{ EXC_TRC,	"trace" },
136 	{ EXC_FPA,	"floating-point assist" },
137 	{ EXC_DEBUG,	"debug" },
138 	{ EXC_PERF,	"performance monitoring" },
139 	{ EXC_VEC,	"altivec unavailable" },
140 	{ EXC_VSX,	"vsx unavailable" },
141 	{ EXC_FAC,	"facility unavailable" },
142 	{ EXC_ITMISS,	"instruction tlb miss" },
143 	{ EXC_DLMISS,	"data load tlb miss" },
144 	{ EXC_DSMISS,	"data store tlb miss" },
145 	{ EXC_BPT,	"instruction breakpoint" },
146 	{ EXC_SMI,	"system management" },
147 	{ EXC_VECAST_G4,	"altivec assist" },
148 	{ EXC_THRM,	"thermal management" },
149 	{ EXC_RUNMODETRC,	"run mode/trace" },
150 	{ EXC_SOFT_PATCH, "soft patch exception" },
151 	{ EXC_LAST,	NULL }
152 };
153 
154 static int uprintf_signal;
155 SYSCTL_INT(_machdep, OID_AUTO, uprintf_signal, CTLFLAG_RWTUN,
156     &uprintf_signal, 0,
157     "Print debugging information on trap signal to ctty");
158 
159 #define ESR_BITMASK							\
160     "\20"								\
161     "\040b0\037b1\036b2\035b3\034PIL\033PRR\032PTR\031FP"		\
162     "\030ST\027b9\026DLK\025ILK\024b12\023b13\022BO\021PIE"		\
163     "\020b16\017b17\016b18\015b19\014b20\013b21\012b22\011b23"		\
164     "\010SPE\007EPID\006b26\005b27\004b28\003b29\002b30\001b31"
165 #define	MCSR_BITMASK							\
166     "\20"								\
167     "\040MCP\037ICERR\036DCERR\035TLBPERR\034L2MMU_MHIT\033b5\032b6\031b7"	\
168     "\030b8\027b9\026b10\025NMI\024MAV\023MEA\022b14\021IF"		\
169     "\020LD\017ST\016LDG\015b19\014b20\013b21\012b22\011b23"		\
170     "\010b24\007b25\006b26\005b27\004b28\003b29\002TLBSYNC\001BSL2_ERR"
171 #define	MSSSR_BITMASK							\
172     "\20"								\
173     "\040b0\037b1\036b2\035b3\034b4\033b5\032b6\031b7"			\
174     "\030b8\027b9\026b10\025b11\024b12\023L2TAG\022L2DAT\021L3TAG"	\
175     "\020L3DAT\017APE\016DPE\015TEA\014b20\013b21\012b22\011b23"	\
176     "\010b24\007b25\006b26\005b27\004b28\003b29\002b30\001b31"
177 
178 static const char *
trapname(u_int vector)179 trapname(u_int vector)
180 {
181 	struct	powerpc_exception *pe;
182 
183 	for (pe = powerpc_exceptions; pe->vector != EXC_LAST; pe++) {
184 		if (pe->vector == vector)
185 			return (pe->name);
186 	}
187 
188 	return ("unknown");
189 }
190 
191 static inline bool
frame_is_trap_inst(struct trapframe * frame)192 frame_is_trap_inst(struct trapframe *frame)
193 {
194 #ifdef AIM
195 	return (frame->exc == EXC_PGM && frame->srr1 & EXC_PGM_TRAP);
196 #else
197 	return ((frame->cpu.booke.esr & ESR_PTR) != 0);
198 #endif
199 }
200 
201 void
trap(struct trapframe * frame)202 trap(struct trapframe *frame)
203 {
204 	struct thread	*td;
205 	struct proc	*p;
206 #ifdef KDTRACE_HOOKS
207 	uint32_t inst;
208 #endif
209 	int		sig, type, user;
210 	u_int		ucode;
211 	ksiginfo_t	ksi;
212 	register_t 	addr, fscr;
213 
214 	VM_CNT_INC(v_trap);
215 
216 #ifdef KDB
217 	if (kdb_active) {
218 		kdb_reenter();
219 		return;
220 	}
221 #endif
222 
223 	td = curthread;
224 	p = td->td_proc;
225 
226 	type = ucode = frame->exc;
227 	sig = 0;
228 	user = frame->srr1 & PSL_PR;
229 	addr = 0;
230 
231 	CTR3(KTR_TRAP, "trap: %s type=%s (%s)", td->td_name,
232 	    trapname(type), user ? "user" : "kernel");
233 
234 #ifdef KDTRACE_HOOKS
235 	/*
236 	 * A trap can occur while DTrace executes a probe. Before
237 	 * executing the probe, DTrace blocks re-scheduling and sets
238 	 * a flag in its per-cpu flags to indicate that it doesn't
239 	 * want to fault. On returning from the probe, the no-fault
240 	 * flag is cleared and finally re-scheduling is enabled.
241 	 *
242 	 * If the DTrace kernel module has registered a trap handler,
243 	 * call it and if it returns non-zero, assume that it has
244 	 * handled the trap and modified the trap frame so that this
245 	 * function can return normally.
246 	 */
247 	if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, type) != 0)
248 		return;
249 #endif
250 
251 	if (user) {
252 		td->td_pticks = 0;
253 		td->td_frame = frame;
254 		addr = frame->srr0;
255 		if (td->td_cowgen != atomic_load_int(&p->p_cowgen))
256 			thread_cow_update(td);
257 
258 		/* User Mode Traps */
259 		switch (type) {
260 		case EXC_RUNMODETRC:
261 		case EXC_TRC:
262 			frame->srr1 &= ~PSL_SE;
263 			sig = SIGTRAP;
264 			ucode = TRAP_TRACE;
265 			break;
266 
267 #if defined(__powerpc64__) && defined(AIM)
268 		case EXC_DSE:
269 			addr = frame->dar;
270 			/* FALLTHROUGH */
271 		case EXC_ISE:
272 			/* DSE/ISE are automatically fatal with radix pmap. */
273 			if (radix_mmu ||
274 			    handle_user_slb_spill(&p->p_vmspace->vm_pmap,
275 			    addr) != 0){
276 				sig = SIGSEGV;
277 				ucode = SEGV_MAPERR;
278 			}
279 			break;
280 #endif
281 		case EXC_DSI:
282 			addr = frame->dar;
283 			/* FALLTHROUGH */
284 		case EXC_ISI:
285 			if (trap_pfault(frame, true, &sig, &ucode))
286 				sig = 0;
287 			break;
288 
289 		case EXC_SC:
290 			syscall(frame);
291 			break;
292 
293 		case EXC_FPU:
294 			KASSERT((td->td_pcb->pcb_flags & PCB_FPU) != PCB_FPU,
295 			    ("FPU already enabled for thread"));
296 			enable_fpu(td);
297 			break;
298 
299 		case EXC_VEC:
300 			KASSERT((td->td_pcb->pcb_flags & PCB_VEC) != PCB_VEC,
301 			    ("Altivec already enabled for thread"));
302 			enable_vec(td);
303 			break;
304 
305 		case EXC_VSX:
306 			KASSERT((td->td_pcb->pcb_flags & PCB_VSX) != PCB_VSX,
307 			    ("VSX already enabled for thread"));
308 			if (!(td->td_pcb->pcb_flags & PCB_VEC))
309 				enable_vec(td);
310 			if (td->td_pcb->pcb_flags & PCB_FPU)
311 				save_fpu(td);
312 			td->td_pcb->pcb_flags |= PCB_VSX;
313 			enable_fpu(td);
314 			break;
315 
316 		case EXC_FAC:
317 			fscr = mfspr(SPR_FSCR);
318 			switch (fscr & FSCR_IC_MASK) {
319 			case FSCR_IC_HTM:
320 				CTR0(KTR_TRAP,
321 				    "Hardware Transactional Memory subsystem disabled");
322 				sig = SIGILL;
323 				ucode =	ILL_ILLOPC;
324 				break;
325 			case FSCR_IC_DSCR:
326 				td->td_pcb->pcb_flags |= PCB_CFSCR | PCB_CDSCR;
327 				fscr |= FSCR_DSCR;
328 				mtspr(SPR_DSCR, 0);
329 				break;
330 			case FSCR_IC_EBB:
331 				td->td_pcb->pcb_flags |= PCB_CFSCR;
332 				fscr |= FSCR_EBB;
333 				mtspr(SPR_EBBHR, 0);
334 				mtspr(SPR_EBBRR, 0);
335 				mtspr(SPR_BESCR, 0);
336 				break;
337 			case FSCR_IC_TAR:
338 				td->td_pcb->pcb_flags |= PCB_CFSCR;
339 				fscr |= FSCR_TAR;
340 				mtspr(SPR_TAR, 0);
341 				break;
342 			case FSCR_IC_LM:
343 				td->td_pcb->pcb_flags |= PCB_CFSCR;
344 				fscr |= FSCR_LM;
345 				mtspr(SPR_LMRR, 0);
346 				mtspr(SPR_LMSER, 0);
347 				break;
348 			default:
349 				sig = SIGILL;
350 				ucode =	ILL_ILLOPC;
351 			}
352 			mtspr(SPR_FSCR, fscr & ~FSCR_IC_MASK);
353 			break;
354 		case EXC_HEA:
355 			sig = SIGILL;
356 			ucode =	ILL_ILLOPC;
357 			break;
358 
359 		case EXC_VECAST_E:
360 		case EXC_VECAST_G4:
361 		case EXC_VECAST_G5:
362 			/*
363 			 * We get a VPU assist exception for IEEE mode
364 			 * vector operations on denormalized floats.
365 			 * Emulating this is a giant pain, so for now,
366 			 * just switch off IEEE mode and treat them as
367 			 * zero.
368 			 */
369 
370 			save_vec(td);
371 			td->td_pcb->pcb_vec.vscr |= ALTIVEC_VSCR_NJ;
372 			enable_vec(td);
373 			break;
374 
375 		case EXC_ALI:
376 			if (fix_unaligned(td, frame) != 0) {
377 				sig = SIGBUS;
378 				ucode = BUS_ADRALN;
379 				addr = frame->dar;
380 			}
381 			else
382 				frame->srr0 += 4;
383 			break;
384 
385 		case EXC_DEBUG:	/* Single stepping */
386 			mtspr(SPR_DBSR, mfspr(SPR_DBSR));
387 			frame->srr1 &= ~PSL_DE;
388 			frame->cpu.booke.dbcr0 &= ~(DBCR0_IDM | DBCR0_IC);
389 			sig = SIGTRAP;
390 			ucode = TRAP_TRACE;
391 			break;
392 
393 		case EXC_PGM:
394 			/* Identify the trap reason */
395 			if (frame_is_trap_inst(frame)) {
396 #ifdef KDTRACE_HOOKS
397 				inst = fuword32((const void *)frame->srr0);
398 				if (inst == 0x0FFFDDDD &&
399 				    dtrace_pid_probe_ptr != NULL) {
400 					(*dtrace_pid_probe_ptr)(frame);
401 					break;
402 				}
403 #endif
404  				sig = SIGTRAP;
405 				ucode = TRAP_BRKPT;
406 				break;
407 			}
408 
409 			if ((frame->srr1 & EXC_PGM_FPENABLED) &&
410 			     (td->td_pcb->pcb_flags & PCB_FPU))
411 				sig = SIGFPE;
412 			else
413 				sig = ppc_instr_emulate(frame, td);
414 
415 			if (sig == SIGILL) {
416 				if (frame->srr1 & EXC_PGM_PRIV)
417 					ucode = ILL_PRVOPC;
418 				else if (frame->srr1 & EXC_PGM_ILLEGAL)
419 					ucode = ILL_ILLOPC;
420 			} else if (sig == SIGFPE) {
421 				ucode = get_fpu_exception(td);
422 			}
423 
424 			break;
425 
426 		case EXC_MCHK:
427 			sig = cpu_machine_check(td, frame, &ucode);
428 			printtrap(frame->exc, frame, 0, (frame->srr1 & PSL_PR));
429 			break;
430 
431 #if defined(__powerpc64__) && defined(AIM)
432 		case EXC_SOFT_PATCH:
433 			/*
434 			 * Point to the instruction that generated the exception to execute it again,
435 			 * and normalize the register values.
436 			 */
437 			frame->srr0 -= 4;
438 			normalize_inputs();
439 			break;
440 #endif
441 
442 		default:
443 			trap_fatal(frame);
444 		}
445 	} else {
446 		/* Kernel Mode Traps */
447 
448 		KASSERT(cold || td->td_ucred != NULL,
449 		    ("kernel trap doesn't have ucred"));
450 		switch (type) {
451 		case EXC_PGM:
452 #ifdef KDTRACE_HOOKS
453 			if (frame_is_trap_inst(frame)) {
454 				if (*(uint32_t *)frame->srr0 == EXC_DTRACE) {
455 					if (dtrace_invop_jump_addr != NULL) {
456 						dtrace_invop_jump_addr(frame);
457 						return;
458 					}
459 				}
460 			}
461 #endif
462 #ifdef KDB
463 			if (db_trap_glue(frame))
464 				return;
465 #endif
466 			break;
467 #if defined(__powerpc64__) && defined(AIM)
468 		case EXC_DSE:
469 			/* DSE on radix mmu is automatically fatal. */
470 			if (radix_mmu)
471 				break;
472 			if (td->td_pcb->pcb_cpu.aim.usr_vsid != 0 &&
473 			    (frame->dar & SEGMENT_MASK) == USER_ADDR) {
474 				__asm __volatile ("slbmte %0, %1" ::
475 					"r"(td->td_pcb->pcb_cpu.aim.usr_vsid),
476 					"r"(USER_SLB_SLBE));
477 				return;
478 			}
479 			break;
480 #endif
481 		case EXC_DSI:
482 			if (trap_pfault(frame, false, NULL, NULL))
483  				return;
484 			break;
485 		case EXC_MCHK:
486 			if (handle_onfault(frame))
487  				return;
488 			break;
489 		default:
490 			break;
491 		}
492 		trap_fatal(frame);
493 	}
494 
495 	if (sig != 0) {
496 		ksiginfo_init_trap(&ksi);
497 		ksi.ksi_signo = sig;
498 		ksi.ksi_code = (int) ucode; /* XXX, not POSIX */
499 		ksi.ksi_addr = (void *)addr;
500 		ksi.ksi_trapno = type;
501 		if (uprintf_signal) {
502 			uprintf("pid %d comm %s: signal %d code %d type 0x%x "
503 				"addr 0x%lx r1 0x%lx srr0 0x%lx srr1 0x%lx\n",
504 			        p->p_pid, p->p_comm, sig, ucode, type,
505 				(u_long)addr, (u_long)frame->fixreg[1],
506 				(u_long)frame->srr0, (u_long)frame->srr1);
507 		}
508 
509 		trapsignal(td, &ksi);
510 	}
511 
512 	userret(td, frame);
513 }
514 
515 static void
trap_fatal(struct trapframe * frame)516 trap_fatal(struct trapframe *frame)
517 {
518 #ifdef KDB
519 	bool handled;
520 #endif
521 
522 	printtrap(frame->exc, frame, 1, (frame->srr1 & PSL_PR));
523 #ifdef KDB
524 	if (debugger_on_trap) {
525 		kdb_why = KDB_WHY_TRAP;
526 		handled = kdb_trap(frame->exc, 0, frame);
527 		kdb_why = KDB_WHY_UNSET;
528 		if (handled)
529 			return;
530 	}
531 #endif
532 	panic("%s trap", trapname(frame->exc));
533 }
534 
535 static void
cpu_printtrap(u_int vector,struct trapframe * frame,int isfatal,int user)536 cpu_printtrap(u_int vector, struct trapframe *frame, int isfatal, int user)
537 {
538 #ifdef AIM
539 	uint16_t ver;
540 
541 	switch (vector) {
542 	case EXC_MCHK:
543 		ver = mfpvr() >> 16;
544 		if (MPC745X_P(ver))
545 			printf("    msssr0         = 0x%b\n",
546 			    (int)mfspr(SPR_MSSSR0), MSSSR_BITMASK);
547 	case EXC_DSE:
548 	case EXC_DSI:
549 	case EXC_DTMISS:
550 		printf("   dsisr           = 0x%lx\n",
551 		    (u_long)frame->cpu.aim.dsisr);
552 		break;
553 	}
554 #elif defined(BOOKE)
555 	vm_paddr_t pa;
556 
557 	switch (vector) {
558 	case EXC_MCHK:
559 		pa = mfspr(SPR_MCARU);
560 		pa = (pa << 32) | (u_register_t)mfspr(SPR_MCAR);
561 		printf("   mcsr            = 0x%b\n",
562 		    (int)mfspr(SPR_MCSR), MCSR_BITMASK);
563 		printf("   mcar            = 0x%jx\n", (uintmax_t)pa);
564 	}
565 	printf("   esr             = 0x%b\n",
566 	    (int)frame->cpu.booke.esr, ESR_BITMASK);
567 #endif
568 }
569 
570 static void
printtrap(u_int vector,struct trapframe * frame,int isfatal,int user)571 printtrap(u_int vector, struct trapframe *frame, int isfatal, int user)
572 {
573 
574 	printf("\n");
575 	printf("%s %s trap:\n", isfatal ? "fatal" : "handled",
576 	    user ? "user" : "kernel");
577 	printf("\n");
578 	printf("   exception       = 0x%x (%s)\n", vector, trapname(vector));
579 	switch (vector) {
580 	case EXC_DSE:
581 	case EXC_DSI:
582 	case EXC_DTMISS:
583 	case EXC_ALI:
584 	case EXC_MCHK:
585 		printf("   virtual address = 0x%" PRIxPTR "\n", frame->dar);
586 		break;
587 	case EXC_ISE:
588 	case EXC_ISI:
589 	case EXC_ITMISS:
590 		printf("   virtual address = 0x%" PRIxPTR "\n", frame->srr0);
591 		break;
592 	}
593 	cpu_printtrap(vector, frame, isfatal, user);
594 	printf("   srr0            = 0x%" PRIxPTR " (0x%" PRIxPTR ")\n",
595 	    frame->srr0, frame->srr0 - (register_t)(__startkernel - KERNBASE));
596 	printf("   srr1            = 0x%lx\n", (u_long)frame->srr1);
597 	printf("   current msr     = 0x%" PRIxPTR "\n", mfmsr());
598 	printf("   lr              = 0x%" PRIxPTR " (0x%" PRIxPTR ")\n",
599 	    frame->lr, frame->lr - (register_t)(__startkernel - KERNBASE));
600 	printf("   frame           = %p\n", frame);
601 	printf("   curthread       = %p\n", curthread);
602 	if (curthread != NULL)
603 		printf("          pid = %d, comm = %s\n",
604 		    curthread->td_proc->p_pid, curthread->td_name);
605 	printf("\n");
606 }
607 
608 /*
609  * Handles a fatal fault when we have onfault state to recover.  Returns
610  * non-zero if there was onfault recovery state available.
611  */
612 static int
handle_onfault(struct trapframe * frame)613 handle_onfault(struct trapframe *frame)
614 {
615 	struct		thread *td;
616 	jmp_buf		*fb;
617 
618 	td = curthread;
619 #if defined(__powerpc64__) || defined(BOOKE)
620 	uintptr_t dispatch = (uintptr_t)td->td_pcb->pcb_onfault;
621 
622 	if (dispatch == 0)
623 		return (0);
624 	/* Short-circuit radix and Book-E paths. */
625 	switch (dispatch) {
626 		case COPYFAULT:
627 			frame->srr0 = (uintptr_t)copy_fault;
628 			return (1);
629 		case FUSUFAULT:
630 			frame->srr0 = (uintptr_t)fusufault;
631 			return (1);
632 		default:
633 			break;
634 	}
635 #endif
636 	fb = td->td_pcb->pcb_onfault;
637 	if (fb != NULL) {
638 		frame->srr0 = (*fb)->_jb[FAULTBUF_LR];
639 		frame->fixreg[1] = (*fb)->_jb[FAULTBUF_R1];
640 		frame->fixreg[2] = (*fb)->_jb[FAULTBUF_R2];
641 		frame->fixreg[3] = 1;
642 		frame->cr = (*fb)->_jb[FAULTBUF_CR];
643 		bcopy(&(*fb)->_jb[FAULTBUF_R14], &frame->fixreg[14],
644 		    18 * sizeof(register_t));
645 		td->td_pcb->pcb_onfault = NULL; /* Returns twice, not thrice */
646 		return (1);
647 	}
648 	return (0);
649 }
650 
651 int
cpu_fetch_syscall_args(struct thread * td)652 cpu_fetch_syscall_args(struct thread *td)
653 {
654 	struct proc *p;
655 	struct trapframe *frame;
656 	struct syscall_args *sa;
657 	caddr_t	params;
658 	size_t argsz;
659 	int error, n, narg, i;
660 
661 	p = td->td_proc;
662 	frame = td->td_frame;
663 	sa = &td->td_sa;
664 
665 	sa->code = frame->fixreg[0];
666 	sa->original_code = sa->code;
667 	params = (caddr_t)(frame->fixreg + FIRSTARG);
668 	n = NARGREG;
669 
670 	if (sa->code == SYS_syscall) {
671 		/*
672 		 * code is first argument,
673 		 * followed by actual args.
674 		 */
675 		sa->code = *(register_t *) params;
676 		params += sizeof(register_t);
677 		n -= 1;
678 	} else if (sa->code == SYS___syscall) {
679 		/*
680 		 * Like syscall, but code is a quad,
681 		 * so as to maintain quad alignment
682 		 * for the rest of the args.
683 		 */
684 		if (SV_PROC_FLAG(p, SV_ILP32)) {
685 			params += sizeof(register_t);
686 			sa->code = *(register_t *) params;
687 			params += sizeof(register_t);
688 			n -= 2;
689 		} else {
690 			sa->code = *(register_t *) params;
691 			params += sizeof(register_t);
692 			n -= 1;
693 		}
694 	}
695 
696 	if (sa->code >= p->p_sysent->sv_size)
697 		sa->callp = &nosys_sysent;
698 	else
699 		sa->callp = &p->p_sysent->sv_table[sa->code];
700 
701 	narg = sa->callp->sy_narg;
702 
703 	if (SV_PROC_FLAG(p, SV_ILP32)) {
704 		argsz = sizeof(uint32_t);
705 
706 		for (i = 0; i < n; i++)
707 			sa->args[i] = ((u_register_t *)(params))[i] &
708 			    0xffffffff;
709 	} else {
710 		argsz = sizeof(uint64_t);
711 
712 		for (i = 0; i < n; i++)
713 			sa->args[i] = ((u_register_t *)(params))[i];
714 	}
715 
716 	if (narg > n)
717 		error = copyin(MOREARGS(frame->fixreg[1]), sa->args + n,
718 			       (narg - n) * argsz);
719 	else
720 		error = 0;
721 
722 #ifdef __powerpc64__
723 	if (SV_PROC_FLAG(p, SV_ILP32) && narg > n) {
724 		/* Expand the size of arguments copied from the stack */
725 
726 		for (i = narg; i >= n; i--)
727 			sa->args[i] = ((uint32_t *)(&sa->args[n]))[i-n];
728 	}
729 #endif
730 
731 	if (error == 0) {
732 		td->td_retval[0] = 0;
733 		td->td_retval[1] = frame->fixreg[FIRSTARG + 1];
734 	}
735 	return (error);
736 }
737 
738 #include "../../kern/subr_syscall.c"
739 
740 void
syscall(struct trapframe * frame)741 syscall(struct trapframe *frame)
742 {
743 	struct thread *td;
744 
745 	td = curthread;
746 	td->td_frame = frame;
747 
748 #if defined(__powerpc64__) && defined(AIM)
749 	/*
750 	 * Speculatively restore last user SLB segment, which we know is
751 	 * invalid already, since we are likely to do copyin()/copyout().
752 	 */
753 	if (td->td_pcb->pcb_cpu.aim.usr_vsid != 0)
754 		__asm __volatile ("slbmte %0, %1; isync" ::
755 		    "r"(td->td_pcb->pcb_cpu.aim.usr_vsid), "r"(USER_SLB_SLBE));
756 #endif
757 
758 	syscallenter(td);
759 	syscallret(td);
760 }
761 
762 static bool
trap_pfault(struct trapframe * frame,bool user,int * signo,int * ucode)763 trap_pfault(struct trapframe *frame, bool user, int *signo, int *ucode)
764 {
765 	vm_offset_t	eva;
766 	struct		thread *td;
767 	struct		proc *p;
768 	vm_map_t	map;
769 	vm_prot_t	ftype;
770 	int		rv, is_user;
771 
772 	td = curthread;
773 	p = td->td_proc;
774 	if (frame->exc == EXC_ISI) {
775 		eva = frame->srr0;
776 		ftype = VM_PROT_EXECUTE;
777 		if (frame->srr1 & SRR1_ISI_PFAULT)
778 			ftype |= VM_PROT_READ;
779 	} else {
780 		eva = frame->dar;
781 #ifdef BOOKE
782 		if (frame->cpu.booke.esr & ESR_ST)
783 #else
784 		if (frame->cpu.aim.dsisr & DSISR_STORE)
785 #endif
786 			ftype = VM_PROT_WRITE;
787 		else
788 			ftype = VM_PROT_READ;
789 	}
790 #if defined(__powerpc64__) && defined(AIM)
791 	if (radix_mmu && pmap_nofault(&p->p_vmspace->vm_pmap, eva, ftype) == 0)
792 		return (true);
793 #endif
794 
795 	if (__predict_false((td->td_pflags & TDP_NOFAULTING) == 0)) {
796 		/*
797 		 * If we get a page fault while in a critical section, then
798 		 * it is most likely a fatal kernel page fault.  The kernel
799 		 * is already going to panic trying to get a sleep lock to
800 		 * do the VM lookup, so just consider it a fatal trap so the
801 		 * kernel can print out a useful trap message and even get
802 		 * to the debugger.
803 		 *
804 		 * If we get a page fault while holding a non-sleepable
805 		 * lock, then it is most likely a fatal kernel page fault.
806 		 * If WITNESS is enabled, then it's going to whine about
807 		 * bogus LORs with various VM locks, so just skip to the
808 		 * fatal trap handling directly.
809 		 */
810 		if (td->td_critnest != 0 ||
811 			WITNESS_CHECK(WARN_SLEEPOK | WARN_GIANTOK, NULL,
812 				"Kernel page fault") != 0) {
813 			trap_fatal(frame);
814 			return (false);
815 		}
816 	}
817 	if (user) {
818 		KASSERT(p->p_vmspace != NULL, ("trap_pfault: vmspace  NULL"));
819 		map = &p->p_vmspace->vm_map;
820 	} else {
821 		rv = pmap_decode_kernel_ptr(eva, &is_user, &eva);
822 		if (rv != 0)
823 			return (false);
824 
825 		if (is_user)
826 			map = &p->p_vmspace->vm_map;
827 		else
828 			map = kernel_map;
829 	}
830 
831 	/* Fault in the page. */
832 	rv = vm_fault_trap(map, eva, ftype, VM_FAULT_NORMAL, signo, ucode);
833 	/*
834 	 * XXXDTRACE: add dtrace_doubletrap_func here?
835 	 */
836 
837 	if (rv == KERN_SUCCESS)
838 		return (true);
839 
840 	if (!user && handle_onfault(frame))
841 		return (true);
842 
843 	return (false);
844 }
845 
846 /*
847  * For now, this only deals with the particular unaligned access case
848  * that gcc tends to generate.  Eventually it should handle all of the
849  * possibilities that can happen on a 32-bit PowerPC in big-endian mode.
850  */
851 
852 static int
fix_unaligned(struct thread * td,struct trapframe * frame)853 fix_unaligned(struct thread *td, struct trapframe *frame)
854 {
855 	struct thread	*fputhread;
856 #ifdef BOOKE
857 	uint32_t	inst;
858 #endif
859 	int		indicator, reg;
860 	double		*fpr;
861 
862 #ifdef __SPE__
863 	indicator = (frame->cpu.booke.esr & (ESR_ST|ESR_SPE));
864 	if (indicator & ESR_SPE) {
865 		if (copyin((void *)frame->srr0, &inst, sizeof(inst)) != 0)
866 			return (-1);
867 		reg = EXC_ALI_INST_RST(inst);
868 		fpr = (double *)td->td_pcb->pcb_vec.vr[reg];
869 		fputhread = PCPU_GET(vecthread);
870 
871 		/* Juggle the SPE to ensure that we've initialized
872 		 * the registers, and that their current state is in
873 		 * the PCB.
874 		 */
875 		if (fputhread != td) {
876 			if (fputhread)
877 				save_vec(fputhread);
878 			enable_vec(td);
879 		}
880 		save_vec(td);
881 
882 		if (!(indicator & ESR_ST)) {
883 			if (copyin((void *)frame->dar, fpr,
884 			    sizeof(double)) != 0)
885 				return (-1);
886 			frame->fixreg[reg] = td->td_pcb->pcb_vec.vr[reg][1];
887 			enable_vec(td);
888 		} else {
889 			td->td_pcb->pcb_vec.vr[reg][1] = frame->fixreg[reg];
890 			if (copyout(fpr, (void *)frame->dar,
891 			    sizeof(double)) != 0)
892 				return (-1);
893 		}
894 		return (0);
895 	}
896 #else
897 #ifdef BOOKE
898 	indicator = (frame->cpu.booke.esr & ESR_ST) ? EXC_ALI_STFD : EXC_ALI_LFD;
899 #else
900 	indicator = EXC_ALI_OPCODE_INDICATOR(frame->cpu.aim.dsisr);
901 #endif
902 
903 	switch (indicator) {
904 	case EXC_ALI_LFD:
905 	case EXC_ALI_STFD:
906 #ifdef BOOKE
907 		if (copyin((void *)frame->srr0, &inst, sizeof(inst)) != 0)
908 			return (-1);
909 		reg = EXC_ALI_INST_RST(inst);
910 #else
911 		reg = EXC_ALI_RST(frame->cpu.aim.dsisr);
912 #endif
913 		fpr = &td->td_pcb->pcb_fpu.fpr[reg].fpr;
914 		fputhread = PCPU_GET(fputhread);
915 
916 		/* Juggle the FPU to ensure that we've initialized
917 		 * the FPRs, and that their current state is in
918 		 * the PCB.
919 		 */
920 		if (fputhread != td) {
921 			if (fputhread)
922 				save_fpu(fputhread);
923 			enable_fpu(td);
924 		}
925 		save_fpu(td);
926 
927 		if (indicator == EXC_ALI_LFD) {
928 			if (copyin((void *)frame->dar, fpr,
929 			    sizeof(double)) != 0)
930 				return (-1);
931 			enable_fpu(td);
932 		} else {
933 			if (copyout(fpr, (void *)frame->dar,
934 			    sizeof(double)) != 0)
935 				return (-1);
936 		}
937 		return (0);
938 		break;
939 	}
940 #endif
941 
942 	return (-1);
943 }
944 
945 #if defined(__powerpc64__) && defined(AIM)
946 #define MSKNSHL(x, m, n) "(((" #x ") & " #m ") << " #n ")"
947 #define MSKNSHR(x, m, n) "(((" #x ") & " #m ") >> " #n ")"
948 
949 /* xvcpsgndp instruction, built in opcode format.
950  * This can be changed to use mnemonic after a toolchain update.
951  */
952 #define XVCPSGNDP(xt, xa, xb) \
953 	__asm __volatile(".long (" \
954 		MSKNSHL(60, 0x3f, 26) " | " \
955 		MSKNSHL(xt, 0x1f, 21) " | " \
956 		MSKNSHL(xa, 0x1f, 16) " | " \
957 		MSKNSHL(xb, 0x1f, 11) " | " \
958 		MSKNSHL(240, 0xff, 3) " | " \
959 		MSKNSHR(xa,  0x20, 3) " | " \
960 		MSKNSHR(xa,  0x20, 4) " | " \
961 		MSKNSHR(xa,  0x20, 5) ")")
962 
963 /* Macros to normalize 1 or 10 VSX registers */
964 #define NORM(x)	XVCPSGNDP(x, x, x)
965 #define NORM10(x) \
966 	NORM(x ## 0); NORM(x ## 1); NORM(x ## 2); NORM(x ## 3); NORM(x ## 4); \
967 	NORM(x ## 5); NORM(x ## 6); NORM(x ## 7); NORM(x ## 8); NORM(x ## 9)
968 
969 static void
normalize_inputs(void)970 normalize_inputs(void)
971 {
972 	register_t msr;
973 
974 	/* enable VSX */
975 	msr = mfmsr();
976 	mtmsr(msr | PSL_VSX);
977 
978 	NORM(0);   NORM(1);   NORM(2);   NORM(3);   NORM(4);
979 	NORM(5);   NORM(6);   NORM(7);   NORM(8);   NORM(9);
980 	NORM10(1); NORM10(2); NORM10(3); NORM10(4); NORM10(5);
981 	NORM(60);  NORM(61);  NORM(62);  NORM(63);
982 
983 	/* restore MSR */
984 	mtmsr(msr);
985 }
986 #endif
987 
988 #ifdef KDB
989 int
db_trap_glue(struct trapframe * frame)990 db_trap_glue(struct trapframe *frame)
991 {
992 
993 	if (!(frame->srr1 & PSL_PR)
994 	    && (frame->exc == EXC_TRC || frame->exc == EXC_RUNMODETRC
995 	    	|| frame_is_trap_inst(frame)
996 		|| frame->exc == EXC_BPT
997 		|| frame->exc == EXC_DEBUG
998 		|| frame->exc == EXC_DSI)) {
999 		int type = frame->exc;
1000 
1001 		/* Ignore DTrace traps. */
1002 		if (*(uint32_t *)frame->srr0 == EXC_DTRACE)
1003 			return (0);
1004 		if (frame_is_trap_inst(frame)) {
1005 			type = T_BREAKPOINT;
1006 		}
1007 		return (kdb_trap(type, 0, frame));
1008 	}
1009 
1010 	return (0);
1011 }
1012 #endif
1013