trap.c revision 260670
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: stable/10/sys/powerpc/aim/trap.c 260670 2014-01-15 05:19:37Z jhibbits $"); 36 37#include "opt_kdtrace.h" 38 39#include <sys/param.h> 40#include <sys/kdb.h> 41#include <sys/proc.h> 42#include <sys/ktr.h> 43#include <sys/lock.h> 44#include <sys/mutex.h> 45#include <sys/pioctl.h> 46#include <sys/ptrace.h> 47#include <sys/reboot.h> 48#include <sys/syscall.h> 49#include <sys/sysent.h> 50#include <sys/systm.h> 51#include <sys/uio.h> 52#include <sys/signalvar.h> 53#include <sys/vmmeter.h> 54 55#include <security/audit/audit.h> 56 57#include <vm/vm.h> 58#include <vm/pmap.h> 59#include <vm/vm_extern.h> 60#include <vm/vm_param.h> 61#include <vm/vm_kern.h> 62#include <vm/vm_map.h> 63#include <vm/vm_page.h> 64 65#include <machine/_inttypes.h> 66#include <machine/altivec.h> 67#include <machine/cpu.h> 68#include <machine/db_machdep.h> 69#include <machine/fpu.h> 70#include <machine/frame.h> 71#include <machine/pcb.h> 72#include <machine/pmap.h> 73#include <machine/psl.h> 74#include <machine/trap.h> 75#include <machine/spr.h> 76#include <machine/sr.h> 77 78static void trap_fatal(struct trapframe *frame); 79static void printtrap(u_int vector, struct trapframe *frame, int isfatal, 80 int user); 81static int trap_pfault(struct trapframe *frame, int user); 82static int fix_unaligned(struct thread *td, struct trapframe *frame); 83static int ppc_instr_emulate(struct trapframe *frame); 84static int handle_onfault(struct trapframe *frame); 85static void syscall(struct trapframe *frame); 86 87#ifdef __powerpc64__ 88 void handle_kernel_slb_spill(int, register_t, register_t); 89static int handle_user_slb_spill(pmap_t pm, vm_offset_t addr); 90extern int n_slbs; 91#endif 92 93int setfault(faultbuf); /* defined in locore.S */ 94 95/* Why are these not defined in a header? */ 96int badaddr(void *, size_t); 97int badaddr_read(void *, size_t, int *); 98 99struct powerpc_exception { 100 u_int vector; 101 char *name; 102}; 103 104#ifdef KDTRACE_HOOKS 105#include <sys/dtrace_bsd.h> 106 107/* 108 * This is a hook which is initialised by the dtrace module 109 * to handle traps which might occur during DTrace probe 110 * execution. 111 */ 112dtrace_trap_func_t dtrace_trap_func; 113 114dtrace_doubletrap_func_t dtrace_doubletrap_func; 115 116/* 117 * This is a hook which is initialised by the systrace module 118 * when it is loaded. This keeps the DTrace syscall provider 119 * implementation opaque. 120 */ 121systrace_probe_func_t systrace_probe_func; 122 123/* 124 * These hooks are necessary for the pid, usdt and fasttrap providers. 125 */ 126dtrace_fasttrap_probe_ptr_t dtrace_fasttrap_probe_ptr; 127dtrace_pid_probe_ptr_t dtrace_pid_probe_ptr; 128dtrace_return_probe_ptr_t dtrace_return_probe_ptr; 129int (*dtrace_invop_jump_addr)(struct trapframe *); 130#endif 131 132static struct powerpc_exception powerpc_exceptions[] = { 133 { 0x0100, "system reset" }, 134 { 0x0200, "machine check" }, 135 { 0x0300, "data storage interrupt" }, 136 { 0x0380, "data segment exception" }, 137 { 0x0400, "instruction storage interrupt" }, 138 { 0x0480, "instruction segment exception" }, 139 { 0x0500, "external interrupt" }, 140 { 0x0600, "alignment" }, 141 { 0x0700, "program" }, 142 { 0x0800, "floating-point unavailable" }, 143 { 0x0900, "decrementer" }, 144 { 0x0c00, "system call" }, 145 { 0x0d00, "trace" }, 146 { 0x0e00, "floating-point assist" }, 147 { 0x0f00, "performance monitoring" }, 148 { 0x0f20, "altivec unavailable" }, 149 { 0x1000, "instruction tlb miss" }, 150 { 0x1100, "data load tlb miss" }, 151 { 0x1200, "data store tlb miss" }, 152 { 0x1300, "instruction breakpoint" }, 153 { 0x1400, "system management" }, 154 { 0x1600, "altivec assist" }, 155 { 0x1700, "thermal management" }, 156 { 0x2000, "run mode/trace" }, 157 { 0x3000, NULL } 158}; 159 160static const char * 161trapname(u_int vector) 162{ 163 struct powerpc_exception *pe; 164 165 for (pe = powerpc_exceptions; pe->vector != 0x3000; pe++) { 166 if (pe->vector == vector) 167 return (pe->name); 168 } 169 170 return ("unknown"); 171} 172 173void 174trap(struct trapframe *frame) 175{ 176 struct thread *td; 177 struct proc *p; 178#ifdef KDTRACE_HOOKS 179 uint32_t inst; 180#endif 181 int sig, type, user; 182 u_int ucode; 183 ksiginfo_t ksi; 184 185 PCPU_INC(cnt.v_trap); 186 187 td = curthread; 188 p = td->td_proc; 189 190 type = ucode = frame->exc; 191 sig = 0; 192 user = frame->srr1 & PSL_PR; 193 194 CTR3(KTR_TRAP, "trap: %s type=%s (%s)", td->td_name, 195 trapname(type), user ? "user" : "kernel"); 196 197#ifdef KDTRACE_HOOKS 198 /* 199 * A trap can occur while DTrace executes a probe. Before 200 * executing the probe, DTrace blocks re-scheduling and sets 201 * a flag in it's per-cpu flags to indicate that it doesn't 202 * want to fault. On returning from the probe, the no-fault 203 * flag is cleared and finally re-scheduling is enabled. 204 * 205 * If the DTrace kernel module has registered a trap handler, 206 * call it and if it returns non-zero, assume that it has 207 * handled the trap and modified the trap frame so that this 208 * function can return normally. 209 */ 210 /* 211 * XXXDTRACE: add fasttrap and pid probes handlers here (if ever) 212 */ 213 if (dtrace_trap_func != NULL && (*dtrace_trap_func)(frame, type)) 214 return; 215#endif 216 217 if (user) { 218 td->td_pticks = 0; 219 td->td_frame = frame; 220 if (td->td_ucred != p->p_ucred) 221 cred_update_thread(td); 222 223 /* User Mode Traps */ 224 switch (type) { 225 case EXC_RUNMODETRC: 226 case EXC_TRC: 227 frame->srr1 &= ~PSL_SE; 228 sig = SIGTRAP; 229 break; 230 231#ifdef __powerpc64__ 232 case EXC_ISE: 233 case EXC_DSE: 234 if (handle_user_slb_spill(&p->p_vmspace->vm_pmap, 235 (type == EXC_ISE) ? frame->srr0 : 236 frame->cpu.aim.dar) != 0) 237 sig = SIGSEGV; 238 break; 239#endif 240 case EXC_DSI: 241 case EXC_ISI: 242 sig = trap_pfault(frame, 1); 243 break; 244 245 case EXC_SC: 246 syscall(frame); 247 break; 248 249 case EXC_FPU: 250 KASSERT((td->td_pcb->pcb_flags & PCB_FPU) != PCB_FPU, 251 ("FPU already enabled for thread")); 252 enable_fpu(td); 253 break; 254 255 case EXC_VEC: 256 KASSERT((td->td_pcb->pcb_flags & PCB_VEC) != PCB_VEC, 257 ("Altivec already enabled for thread")); 258 enable_vec(td); 259 break; 260 261 case EXC_VECAST_G4: 262 case EXC_VECAST_G5: 263 /* 264 * We get a VPU assist exception for IEEE mode 265 * vector operations on denormalized floats. 266 * Emulating this is a giant pain, so for now, 267 * just switch off IEEE mode and treat them as 268 * zero. 269 */ 270 271 save_vec(td); 272 td->td_pcb->pcb_vec.vscr |= ALTIVEC_VSCR_NJ; 273 enable_vec(td); 274 break; 275 276 case EXC_ALI: 277 if (fix_unaligned(td, frame) != 0) 278 sig = SIGBUS; 279 else 280 frame->srr0 += 4; 281 break; 282 283 case EXC_PGM: 284 /* Identify the trap reason */ 285 if (frame->srr1 & EXC_PGM_TRAP) { 286#ifdef KDTRACE_HOOKS 287 inst = fuword32((const void *)frame->srr0); 288 if (inst == 0x0FFFDDDD && dtrace_pid_probe_ptr != NULL) { 289 struct reg regs; 290 fill_regs(td, ®s); 291 (*dtrace_pid_probe_ptr)(®s); 292 break; 293 } 294#endif 295 sig = SIGTRAP; 296 } else if (ppc_instr_emulate(frame) == 0) 297 frame->srr0 += 4; 298 else 299 sig = SIGILL; 300 break; 301 302 default: 303 trap_fatal(frame); 304 } 305 } else { 306 /* Kernel Mode Traps */ 307 308 KASSERT(cold || td->td_ucred != NULL, 309 ("kernel trap doesn't have ucred")); 310 switch (type) { 311#ifdef KDTRACE_HOOKS 312 case EXC_PGM: 313 if (frame->srr1 & EXC_PGM_TRAP) { 314 if (*(uint32_t *)frame->srr0 == 0x7c810808) { 315 if (dtrace_invop_jump_addr != NULL) { 316 dtrace_invop_jump_addr(frame); 317 return; 318 } 319 } 320 } 321 break; 322#endif 323#ifdef __powerpc64__ 324 case EXC_DSE: 325 if ((frame->cpu.aim.dar & SEGMENT_MASK) == USER_ADDR) { 326 __asm __volatile ("slbmte %0, %1" :: 327 "r"(td->td_pcb->pcb_cpu.aim.usr_vsid), 328 "r"(USER_SLB_SLBE)); 329 return; 330 } 331 break; 332#endif 333 case EXC_DSI: 334 if (trap_pfault(frame, 0) == 0) 335 return; 336 break; 337 case EXC_MCHK: 338 if (handle_onfault(frame)) 339 return; 340 break; 341 default: 342 break; 343 } 344 trap_fatal(frame); 345 } 346 347 if (sig != 0) { 348 if (p->p_sysent->sv_transtrap != NULL) 349 sig = (p->p_sysent->sv_transtrap)(sig, type); 350 ksiginfo_init_trap(&ksi); 351 ksi.ksi_signo = sig; 352 ksi.ksi_code = (int) ucode; /* XXX, not POSIX */ 353 /* ksi.ksi_addr = ? */ 354 ksi.ksi_trapno = type; 355 trapsignal(td, &ksi); 356 } 357 358 userret(td, frame); 359} 360 361static void 362trap_fatal(struct trapframe *frame) 363{ 364 365 printtrap(frame->exc, frame, 1, (frame->srr1 & PSL_PR)); 366#ifdef KDB 367 if ((debugger_on_panic || kdb_active) && 368 kdb_trap(frame->exc, 0, frame)) 369 return; 370#endif 371 panic("%s trap", trapname(frame->exc)); 372} 373 374static void 375printtrap(u_int vector, struct trapframe *frame, int isfatal, int user) 376{ 377 378 printf("\n"); 379 printf("%s %s trap:\n", isfatal ? "fatal" : "handled", 380 user ? "user" : "kernel"); 381 printf("\n"); 382 printf(" exception = 0x%x (%s)\n", vector, trapname(vector)); 383 switch (vector) { 384 case EXC_DSE: 385 case EXC_DSI: 386 printf(" virtual address = 0x%" PRIxPTR "\n", 387 frame->cpu.aim.dar); 388 printf(" dsisr = 0x%" PRIxPTR "\n", 389 frame->cpu.aim.dsisr); 390 break; 391 case EXC_ISE: 392 case EXC_ISI: 393 printf(" virtual address = 0x%" PRIxPTR "\n", frame->srr0); 394 break; 395 } 396 printf(" srr0 = 0x%" PRIxPTR "\n", frame->srr0); 397 printf(" srr1 = 0x%" PRIxPTR "\n", frame->srr1); 398 printf(" lr = 0x%" PRIxPTR "\n", frame->lr); 399 printf(" curthread = %p\n", curthread); 400 if (curthread != NULL) 401 printf(" pid = %d, comm = %s\n", 402 curthread->td_proc->p_pid, curthread->td_name); 403 printf("\n"); 404} 405 406/* 407 * Handles a fatal fault when we have onfault state to recover. Returns 408 * non-zero if there was onfault recovery state available. 409 */ 410static int 411handle_onfault(struct trapframe *frame) 412{ 413 struct thread *td; 414 faultbuf *fb; 415 416 td = curthread; 417 fb = td->td_pcb->pcb_onfault; 418 if (fb != NULL) { 419 frame->srr0 = (*fb)[0]; 420 frame->fixreg[1] = (*fb)[1]; 421 frame->fixreg[2] = (*fb)[2]; 422 frame->fixreg[3] = 1; 423 frame->cr = (*fb)[3]; 424 bcopy(&(*fb)[4], &frame->fixreg[13], 425 19 * sizeof(register_t)); 426 return (1); 427 } 428 return (0); 429} 430 431int 432cpu_fetch_syscall_args(struct thread *td, struct syscall_args *sa) 433{ 434 struct proc *p; 435 struct trapframe *frame; 436 caddr_t params; 437 size_t argsz; 438 int error, n, i; 439 440 p = td->td_proc; 441 frame = td->td_frame; 442 443 sa->code = frame->fixreg[0]; 444 params = (caddr_t)(frame->fixreg + FIRSTARG); 445 n = NARGREG; 446 447 if (sa->code == SYS_syscall) { 448 /* 449 * code is first argument, 450 * followed by actual args. 451 */ 452 sa->code = *(register_t *) params; 453 params += sizeof(register_t); 454 n -= 1; 455 } else if (sa->code == SYS___syscall) { 456 /* 457 * Like syscall, but code is a quad, 458 * so as to maintain quad alignment 459 * for the rest of the args. 460 */ 461 if (SV_PROC_FLAG(p, SV_ILP32)) { 462 params += sizeof(register_t); 463 sa->code = *(register_t *) params; 464 params += sizeof(register_t); 465 n -= 2; 466 } else { 467 sa->code = *(register_t *) params; 468 params += sizeof(register_t); 469 n -= 1; 470 } 471 } 472 473 if (p->p_sysent->sv_mask) 474 sa->code &= p->p_sysent->sv_mask; 475 if (sa->code >= p->p_sysent->sv_size) 476 sa->callp = &p->p_sysent->sv_table[0]; 477 else 478 sa->callp = &p->p_sysent->sv_table[sa->code]; 479 480 sa->narg = sa->callp->sy_narg; 481 482 if (SV_PROC_FLAG(p, SV_ILP32)) { 483 argsz = sizeof(uint32_t); 484 485 for (i = 0; i < n; i++) 486 sa->args[i] = ((u_register_t *)(params))[i] & 487 0xffffffff; 488 } else { 489 argsz = sizeof(uint64_t); 490 491 for (i = 0; i < n; i++) 492 sa->args[i] = ((u_register_t *)(params))[i]; 493 } 494 495 if (sa->narg > n) 496 error = copyin(MOREARGS(frame->fixreg[1]), sa->args + n, 497 (sa->narg - n) * argsz); 498 else 499 error = 0; 500 501#ifdef __powerpc64__ 502 if (SV_PROC_FLAG(p, SV_ILP32) && sa->narg > n) { 503 /* Expand the size of arguments copied from the stack */ 504 505 for (i = sa->narg; i >= n; i--) 506 sa->args[i] = ((uint32_t *)(&sa->args[n]))[i-n]; 507 } 508#endif 509 510 if (error == 0) { 511 td->td_retval[0] = 0; 512 td->td_retval[1] = frame->fixreg[FIRSTARG + 1]; 513 } 514 return (error); 515} 516 517#include "../../kern/subr_syscall.c" 518 519void 520syscall(struct trapframe *frame) 521{ 522 struct thread *td; 523 struct syscall_args sa; 524 int error; 525 526 td = curthread; 527 td->td_frame = frame; 528 529#ifdef __powerpc64__ 530 /* 531 * Speculatively restore last user SLB segment, which we know is 532 * invalid already, since we are likely to do copyin()/copyout(). 533 */ 534 __asm __volatile ("slbmte %0, %1; isync" :: 535 "r"(td->td_pcb->pcb_cpu.aim.usr_vsid), "r"(USER_SLB_SLBE)); 536#endif 537 538 error = syscallenter(td, &sa); 539 syscallret(td, error, &sa); 540} 541 542#ifdef __powerpc64__ 543/* Handle kernel SLB faults -- runs in real mode, all seat belts off */ 544void 545handle_kernel_slb_spill(int type, register_t dar, register_t srr0) 546{ 547 struct slb *slbcache; 548 uint64_t slbe, slbv; 549 uint64_t esid, addr; 550 int i; 551 552 addr = (type == EXC_ISE) ? srr0 : dar; 553 slbcache = PCPU_GET(slb); 554 esid = (uintptr_t)addr >> ADDR_SR_SHFT; 555 slbe = (esid << SLBE_ESID_SHIFT) | SLBE_VALID; 556 557 /* See if the hardware flushed this somehow (can happen in LPARs) */ 558 for (i = 0; i < n_slbs; i++) 559 if (slbcache[i].slbe == (slbe | (uint64_t)i)) 560 return; 561 562 /* Not in the map, needs to actually be added */ 563 slbv = kernel_va_to_slbv(addr); 564 if (slbcache[USER_SLB_SLOT].slbe == 0) { 565 for (i = 0; i < n_slbs; i++) { 566 if (i == USER_SLB_SLOT) 567 continue; 568 if (!(slbcache[i].slbe & SLBE_VALID)) 569 goto fillkernslb; 570 } 571 572 if (i == n_slbs) 573 slbcache[USER_SLB_SLOT].slbe = 1; 574 } 575 576 /* Sacrifice a random SLB entry that is not the user entry */ 577 i = mftb() % n_slbs; 578 if (i == USER_SLB_SLOT) 579 i = (i+1) % n_slbs; 580 581fillkernslb: 582 /* Write new entry */ 583 slbcache[i].slbv = slbv; 584 slbcache[i].slbe = slbe | (uint64_t)i; 585 586 /* Trap handler will restore from cache on exit */ 587} 588 589static int 590handle_user_slb_spill(pmap_t pm, vm_offset_t addr) 591{ 592 struct slb *user_entry; 593 uint64_t esid; 594 int i; 595 596 esid = (uintptr_t)addr >> ADDR_SR_SHFT; 597 598 PMAP_LOCK(pm); 599 user_entry = user_va_to_slb_entry(pm, addr); 600 601 if (user_entry == NULL) { 602 /* allocate_vsid auto-spills it */ 603 (void)allocate_user_vsid(pm, esid, 0); 604 } else { 605 /* 606 * Check that another CPU has not already mapped this. 607 * XXX: Per-thread SLB caches would be better. 608 */ 609 for (i = 0; i < pm->pm_slb_len; i++) 610 if (pm->pm_slb[i] == user_entry) 611 break; 612 613 if (i == pm->pm_slb_len) 614 slb_insert_user(pm, user_entry); 615 } 616 PMAP_UNLOCK(pm); 617 618 return (0); 619} 620#endif 621 622static int 623trap_pfault(struct trapframe *frame, int user) 624{ 625 vm_offset_t eva, va; 626 struct thread *td; 627 struct proc *p; 628 vm_map_t map; 629 vm_prot_t ftype; 630 int rv; 631 register_t user_sr; 632 633 td = curthread; 634 p = td->td_proc; 635 if (frame->exc == EXC_ISI) { 636 eva = frame->srr0; 637 ftype = VM_PROT_EXECUTE; 638 if (frame->srr1 & SRR1_ISI_PFAULT) 639 ftype |= VM_PROT_READ; 640 } else { 641 eva = frame->cpu.aim.dar; 642 if (frame->cpu.aim.dsisr & DSISR_STORE) 643 ftype = VM_PROT_WRITE; 644 else 645 ftype = VM_PROT_READ; 646 } 647 648 if (user) { 649 map = &p->p_vmspace->vm_map; 650 } else { 651 if ((eva >> ADDR_SR_SHFT) == (USER_ADDR >> ADDR_SR_SHFT)) { 652 if (p->p_vmspace == NULL) 653 return (SIGSEGV); 654 655 map = &p->p_vmspace->vm_map; 656 657 user_sr = td->td_pcb->pcb_cpu.aim.usr_segm; 658 eva &= ADDR_PIDX | ADDR_POFF; 659 eva |= user_sr << ADDR_SR_SHFT; 660 } else { 661 map = kernel_map; 662 } 663 } 664 va = trunc_page(eva); 665 666 if (map != kernel_map) { 667 /* 668 * Keep swapout from messing with us during this 669 * critical time. 670 */ 671 PROC_LOCK(p); 672 ++p->p_lock; 673 PROC_UNLOCK(p); 674 675 /* Fault in the user page: */ 676 rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL); 677 678 PROC_LOCK(p); 679 --p->p_lock; 680 PROC_UNLOCK(p); 681 /* 682 * XXXDTRACE: add dtrace_doubletrap_func here? 683 */ 684 } else { 685 /* 686 * Don't have to worry about process locking or stacks in the 687 * kernel. 688 */ 689 rv = vm_fault(map, va, ftype, VM_FAULT_NORMAL); 690 } 691 692 if (rv == KERN_SUCCESS) 693 return (0); 694 695 if (!user && handle_onfault(frame)) 696 return (0); 697 698 return (SIGSEGV); 699} 700 701int 702badaddr(void *addr, size_t size) 703{ 704 return (badaddr_read(addr, size, NULL)); 705} 706 707int 708badaddr_read(void *addr, size_t size, int *rptr) 709{ 710 struct thread *td; 711 faultbuf env; 712 int x; 713 714 /* Get rid of any stale machine checks that have been waiting. */ 715 __asm __volatile ("sync; isync"); 716 717 td = curthread; 718 719 if (setfault(env)) { 720 td->td_pcb->pcb_onfault = 0; 721 __asm __volatile ("sync"); 722 return 1; 723 } 724 725 __asm __volatile ("sync"); 726 727 switch (size) { 728 case 1: 729 x = *(volatile int8_t *)addr; 730 break; 731 case 2: 732 x = *(volatile int16_t *)addr; 733 break; 734 case 4: 735 x = *(volatile int32_t *)addr; 736 break; 737 default: 738 panic("badaddr: invalid size (%zd)", size); 739 } 740 741 /* Make sure we took the machine check, if we caused one. */ 742 __asm __volatile ("sync; isync"); 743 744 td->td_pcb->pcb_onfault = 0; 745 __asm __volatile ("sync"); /* To be sure. */ 746 747 /* Use the value to avoid reorder. */ 748 if (rptr) 749 *rptr = x; 750 751 return (0); 752} 753 754/* 755 * For now, this only deals with the particular unaligned access case 756 * that gcc tends to generate. Eventually it should handle all of the 757 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 758 */ 759 760static int 761fix_unaligned(struct thread *td, struct trapframe *frame) 762{ 763 struct thread *fputhread; 764 int indicator, reg; 765 double *fpr; 766 767 indicator = EXC_ALI_OPCODE_INDICATOR(frame->cpu.aim.dsisr); 768 769 switch (indicator) { 770 case EXC_ALI_LFD: 771 case EXC_ALI_STFD: 772 reg = EXC_ALI_RST(frame->cpu.aim.dsisr); 773 fpr = &td->td_pcb->pcb_fpu.fpr[reg]; 774 fputhread = PCPU_GET(fputhread); 775 776 /* Juggle the FPU to ensure that we've initialized 777 * the FPRs, and that their current state is in 778 * the PCB. 779 */ 780 if (fputhread != td) { 781 if (fputhread) 782 save_fpu(fputhread); 783 enable_fpu(td); 784 } 785 save_fpu(td); 786 787 if (indicator == EXC_ALI_LFD) { 788 if (copyin((void *)frame->cpu.aim.dar, fpr, 789 sizeof(double)) != 0) 790 return -1; 791 enable_fpu(td); 792 } else { 793 if (copyout(fpr, (void *)frame->cpu.aim.dar, 794 sizeof(double)) != 0) 795 return -1; 796 } 797 return 0; 798 break; 799 } 800 801 return -1; 802} 803 804static int 805ppc_instr_emulate(struct trapframe *frame) 806{ 807 uint32_t instr; 808 int reg; 809 810 instr = fuword32((void *)frame->srr0); 811 812 if ((instr & 0xfc1fffff) == 0x7c1f42a6) { /* mfpvr */ 813 reg = (instr & ~0xfc1fffff) >> 21; 814 frame->fixreg[reg] = mfpvr(); 815 return (0); 816 } 817 818 return (-1); 819} 820 821