trap.c revision 1.30
1/* $NetBSD: trap.c,v 1.30 2006/03/07 03:32:05 thorpej Exp $ */ 2 3/* 4 * Copyright 2001 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38/* 39 * Copyright (C) 1995, 1996 Wolfgang Solfrank. 40 * Copyright (C) 1995, 1996 TooLs GmbH. 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by TooLs GmbH. 54 * 4. The name of TooLs GmbH may not be used to endorse or promote products 55 * derived from this software without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 60 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 61 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 62 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 63 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 64 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 65 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 66 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69#include <sys/cdefs.h> 70__KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.30 2006/03/07 03:32:05 thorpej Exp $"); 71 72#include "opt_altivec.h" 73#include "opt_ddb.h" 74#include "opt_syscall_debug.h" 75 76#include <sys/param.h> 77#include <sys/proc.h> 78#include <sys/reboot.h> 79#include <sys/syscall.h> 80#include <sys/systm.h> 81#include <sys/user.h> 82#include <sys/pool.h> 83#include <sys/sa.h> 84#include <sys/savar.h> 85#include <sys/userret.h> 86 87#include <uvm/uvm_extern.h> 88 89#include <dev/cons.h> 90 91#include <machine/cpu.h> 92#include <machine/db_machdep.h> 93#include <machine/fpu.h> 94#include <machine/frame.h> 95#include <machine/pcb.h> 96#include <machine/psl.h> 97#include <machine/trap.h> 98 99#include <powerpc/spr.h> 100#include <powerpc/ibm4xx/pmap.h> 101#include <powerpc/ibm4xx/tlb.h> 102#include <powerpc/fpu/fpu_extern.h> 103 104/* These definitions should probably be somewhere else XXX */ 105#define FIRSTARG 3 /* first argument is in reg 3 */ 106#define NARGREG 8 /* 8 args are in registers */ 107#define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */ 108 109static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 110 111void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 112/* Why are these not defined in a header? */ 113int badaddr __P((void *, size_t)); 114int badaddr_read __P((void *, size_t, int *)); 115int ctx_setup __P((int, int)); 116 117#ifdef DEBUG 118#define TDB_ALL 0x1 119int trapdebug = /* TDB_ALL */ 0; 120#define DBPRINTF(x, y) if (trapdebug & (x)) printf y 121#else 122#define DBPRINTF(x, y) 123#endif 124 125void 126trap(struct trapframe *frame) 127{ 128 struct lwp *l = curlwp; 129 struct proc *p = l ? l->l_proc : NULL; 130 int type = frame->exc; 131 int ftype, rv; 132 ksiginfo_t ksi; 133 134 KASSERT(l == 0 || (l->l_stat == LSONPROC)); 135 136 if (frame->srr1 & PSL_PR) 137 type |= EXC_USER; 138 139 ftype = VM_PROT_READ; 140 141 DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n", 142 type, frame->srr0, frame, &frame)); 143 144 switch (type) { 145 case EXC_DEBUG|EXC_USER: 146 { 147 int srr2, srr3; 148 149 __asm volatile("mfspr %0,0x3f0" : 150 "=r" (rv), "=r" (srr2), "=r" (srr3) :); 151 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, 152 srr3); 153 /* XXX fall through or break here?! */ 154 } 155 /* 156 * DEBUG intr -- probably single-step. 157 */ 158 case EXC_TRC|EXC_USER: 159 frame->srr1 &= ~PSL_SE; 160 KSI_INIT_TRAP(&ksi); 161 ksi.ksi_signo = SIGTRAP; 162 ksi.ksi_trap = EXC_TRC; 163 ksi.ksi_addr = (void *)frame->srr0; 164 KERNEL_PROC_LOCK(l); 165 trapsignal(l, &ksi); 166 KERNEL_PROC_UNLOCK(l); 167 break; 168 169 /* 170 * If we could not find and install appropriate TLB entry, fall through. 171 */ 172 173 case EXC_DSI: 174 /* FALLTHROUGH */ 175 case EXC_DTMISS: 176 { 177 struct vm_map *map; 178 vaddr_t va; 179 struct faultbuf *fb = NULL; 180 181 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE); 182 va = frame->dar; 183 if (frame->tf_xtra[TF_PID] == KERNEL_PID) { 184 map = kernel_map; 185 } else { 186 map = &p->p_vmspace->vm_map; 187 if (l->l_flag & L_SA) { 188 l->l_savp->savp_faultaddr = va; 189 l->l_flag |= L_SA_PAGEFAULT; 190 } 191 } 192 193 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 194 ftype = VM_PROT_WRITE; 195 196 DBPRINTF(TDB_ALL, 197 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 198 frame->srr0, 199 (ftype & VM_PROT_WRITE) ? "write" : "read", 200 (void *)va, frame->tf_xtra[TF_ESR])); 201 rv = uvm_fault(map, trunc_page(va), 0, ftype); 202 KERNEL_UNLOCK(); 203 if (map != kernel_map) 204 l->l_flag &= ~L_SA_PAGEFAULT; 205 if (rv == 0) 206 goto done; 207 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 208 frame->tf_xtra[TF_PID] = KERNEL_PID; 209 frame->srr0 = fb->fb_pc; 210 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 211 frame->fixreg[1] = fb->fb_sp; 212 frame->fixreg[2] = fb->fb_r2; 213 frame->fixreg[3] = 1; /* Return TRUE */ 214 frame->cr = fb->fb_cr; 215 memcpy(&frame->fixreg[13], fb->fb_fixreg, 216 sizeof(fb->fb_fixreg)); 217 goto done; 218 } 219 } 220 goto brain_damage; 221 222 case EXC_DSI|EXC_USER: 223 /* FALLTHROUGH */ 224 case EXC_DTMISS|EXC_USER: 225 KERNEL_PROC_LOCK(l); 226 227 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 228 ftype = VM_PROT_WRITE; 229 230 DBPRINTF(TDB_ALL, 231 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 232 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 233 frame->dar, frame->tf_xtra[TF_ESR])); 234 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 235 if (l->l_flag & L_SA) { 236 l->l_savp->savp_faultaddr = (vaddr_t)frame->dar; 237 l->l_flag |= L_SA_PAGEFAULT; 238 } 239 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 240 0, ftype); 241 if (rv == 0) { 242 l->l_flag &= ~L_SA_PAGEFAULT; 243 KERNEL_PROC_UNLOCK(l); 244 break; 245 } 246 KSI_INIT_TRAP(&ksi); 247 ksi.ksi_signo = SIGSEGV; 248 ksi.ksi_trap = EXC_DSI; 249 ksi.ksi_addr = (void *)frame->dar; 250 if (rv == ENOMEM) { 251 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 252 "out of swap\n", 253 p->p_pid, p->p_comm, l->l_lid, 254 p->p_cred && p->p_ucred ? 255 p->p_ucred->cr_uid : -1); 256 ksi.ksi_signo = SIGKILL; 257 } 258 trapsignal(l, &ksi); 259 l->l_flag &= ~L_SA_PAGEFAULT; 260 KERNEL_PROC_UNLOCK(l); 261 break; 262 263 case EXC_ITMISS|EXC_USER: 264 case EXC_ISI|EXC_USER: 265 KERNEL_PROC_LOCK(l); 266 if (l->l_flag & L_SA) { 267 l->l_savp->savp_faultaddr = (vaddr_t)frame->srr0; 268 l->l_flag |= L_SA_PAGEFAULT; 269 } 270 ftype = VM_PROT_EXECUTE; 271 DBPRINTF(TDB_ALL, 272 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 273 frame->srr0, frame)); 274 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 275 0, ftype); 276 if (rv == 0) { 277 l->l_flag &= ~L_SA_PAGEFAULT; 278 KERNEL_PROC_UNLOCK(l); 279 break; 280 } 281 KSI_INIT_TRAP(&ksi); 282 ksi.ksi_signo = SIGSEGV; 283 ksi.ksi_trap = EXC_ISI; 284 ksi.ksi_addr = (void *)frame->srr0; 285 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR); 286 trapsignal(l, &ksi); 287 l->l_flag &= ~L_SA_PAGEFAULT; 288 KERNEL_PROC_UNLOCK(l); 289 break; 290 291 case EXC_AST|EXC_USER: 292 curcpu()->ci_astpending = 0; /* we are about to do it */ 293 KERNEL_PROC_LOCK(l); 294 uvmexp.softs++; 295 if (p->p_flag & P_OWEUPC) { 296 p->p_flag &= ~P_OWEUPC; 297 ADDUPROF(p); 298 } 299 /* Check whether we are being preempted. */ 300 if (curcpu()->ci_want_resched) 301 preempt(0); 302 KERNEL_PROC_UNLOCK(l); 303 break; 304 305 306 case EXC_ALI|EXC_USER: 307 KERNEL_PROC_LOCK(l); 308 if (fix_unaligned(l, frame) != 0) { 309 KSI_INIT_TRAP(&ksi); 310 ksi.ksi_signo = SIGBUS; 311 ksi.ksi_trap = EXC_ALI; 312 ksi.ksi_addr = (void *)frame->dar; 313 trapsignal(l, &ksi); 314 } else 315 frame->srr0 += 4; 316 KERNEL_PROC_UNLOCK(l); 317 break; 318 319 case EXC_PGM|EXC_USER: 320 /* 321 * Illegal insn: 322 * 323 * let's try to see if it's FPU and can be emulated. 324 */ 325 uvmexp.traps++; 326 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 327 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 328 sizeof l->l_addr->u_pcb.pcb_fpu); 329 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 330 } 331 332 if ((rv = fpu_emulate(frame, 333 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 334 KSI_INIT_TRAP(&ksi); 335 ksi.ksi_signo = rv; 336 ksi.ksi_trap = EXC_PGM; 337 ksi.ksi_addr = (void *)frame->srr0; 338 KERNEL_PROC_LOCK(l); 339 trapsignal(l, &ksi); 340 KERNEL_PROC_UNLOCK(l); 341 } 342 break; 343 344 case EXC_MCHK: 345 { 346 struct faultbuf *fb; 347 348 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 349 frame->tf_xtra[TF_PID] = KERNEL_PID; 350 frame->srr0 = fb->fb_pc; 351 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 352 frame->fixreg[1] = fb->fb_sp; 353 frame->fixreg[2] = fb->fb_r2; 354 frame->fixreg[3] = 1; /* Return TRUE */ 355 frame->cr = fb->fb_cr; 356 memcpy(&frame->fixreg[13], fb->fb_fixreg, 357 sizeof(fb->fb_fixreg)); 358 goto done; 359 } 360 } 361 goto brain_damage; 362 default: 363 brain_damage: 364 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 365#ifdef DDB 366 if (kdb_trap(type, frame)) 367 goto done; 368#endif 369#ifdef TRAP_PANICWAIT 370 printf("Press a key to panic.\n"); 371 cngetc(); 372#endif 373 panic("trap"); 374 } 375 376 /* Invoke MI userret code */ 377 mi_userret(l); 378 379 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 380 done: 381 return; 382} 383 384int 385ctx_setup(int ctx, int srr1) 386{ 387 volatile struct pmap *pm; 388 389 /* Update PID if we're returning to user mode. */ 390 if (srr1 & PSL_PR) { 391 pm = curproc->p_vmspace->vm_map.pmap; 392 if (!pm->pm_ctx) { 393 ctx_alloc(__UNVOLATILE(pm)); 394 } 395 ctx = pm->pm_ctx; 396 if (srr1 & PSL_SE) { 397 int dbreg, mask = 0x48000000; 398 /* 399 * Set the Internal Debug and 400 * Instruction Completion bits of 401 * the DBCR0 register. 402 * 403 * XXX this is also used by jtag debuggers... 404 */ 405 __asm volatile("mfspr %0,0x3f2;" 406 "or %0,%0,%1;" 407 "mtspr 0x3f2,%0;" : 408 "=&r" (dbreg) : "r" (mask)); 409 } 410 } 411 else if (!ctx) { 412 ctx = KERNEL_PID; 413 } 414 return (ctx); 415} 416 417/* 418 * Used by copyin()/copyout() 419 */ 420extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 421extern void vunmaprange __P((vaddr_t, vsize_t)); 422static int bigcopyin __P((const void *, void *, size_t )); 423static int bigcopyout __P((const void *, void *, size_t )); 424 425int 426copyin(const void *udaddr, void *kaddr, size_t len) 427{ 428 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 429 int msr, pid, tmp, ctx; 430 struct faultbuf env; 431 432 /* For bigger buffers use the faster copy */ 433 if (len > 256) 434 return (bigcopyin(udaddr, kaddr, len)); 435 436 if (setfault(&env)) { 437 curpcb->pcb_onfault = 0; 438 return EFAULT; 439 } 440 441 if (!(ctx = pm->pm_ctx)) { 442 /* No context -- assign it one */ 443 ctx_alloc(pm); 444 ctx = pm->pm_ctx; 445 } 446 447 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 448 "mfmsr %0;" /* Save MSR */ 449 "li %1,0x20; " 450 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 451 "mfpid %1;" /* Save old PID */ 452 "sync; isync;" 453 454 "1: bdz 2f;" /* while len */ 455 "mtpid %3; sync;" /* Load user ctx */ 456 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 457 "sync; isync;" 458 "mtpid %1;sync;" 459 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 460 "sync; isync;" 461 "b 1b;" /* repeat */ 462 463 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 464 "sync; isync;" 465 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 466 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len)); 467 468 curpcb->pcb_onfault = 0; 469 return 0; 470} 471 472static int 473bigcopyin(const void *udaddr, void *kaddr, size_t len) 474{ 475 const char *up; 476 char *kp = kaddr; 477 struct lwp *l = curlwp; 478 struct proc *p; 479 int error; 480 481 if (!l) { 482 return EFAULT; 483 } 484 485 p = l->l_proc; 486 487 /* 488 * Stolen from physio(): 489 */ 490 PHOLD(l); 491 error = uvm_vslock(p, __UNCONST(udaddr), len, VM_PROT_READ); 492 if (error) { 493 PRELE(l); 494 return EFAULT; 495 } 496 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 497 498 memcpy(kp, up, len); 499 vunmaprange((vaddr_t)up, len); 500 uvm_vsunlock(p, __UNCONST(udaddr), len); 501 PRELE(l); 502 503 return 0; 504} 505 506int 507copyout(const void *kaddr, void *udaddr, size_t len) 508{ 509 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 510 int msr, pid, tmp, ctx; 511 struct faultbuf env; 512 513 /* For big copies use more efficient routine */ 514 if (len > 256) 515 return (bigcopyout(kaddr, udaddr, len)); 516 517 if (setfault(&env)) { 518 curpcb->pcb_onfault = 0; 519 return EFAULT; 520 } 521 522 if (!(ctx = pm->pm_ctx)) { 523 /* No context -- assign it one */ 524 ctx_alloc(pm); 525 ctx = pm->pm_ctx; 526 } 527 528 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 529 "mfmsr %0;" /* Save MSR */ 530 "li %1,0x20; " 531 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 532 "mfpid %1;" /* Save old PID */ 533 "sync; isync;" 534 535 "1: bdz 2f;" /* while len */ 536 "mtpid %1;sync;" 537 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 538 "sync; isync;" 539 "mtpid %3; sync;" /* Load user ctx */ 540 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 541 "sync; isync;" 542 "b 1b;" /* repeat */ 543 544 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 545 "sync; isync;" 546 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 547 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len)); 548 549 curpcb->pcb_onfault = 0; 550 return 0; 551} 552 553static int 554bigcopyout(const void *kaddr, void *udaddr, size_t len) 555{ 556 char *up; 557 const char *kp = (const char *)kaddr; 558 struct lwp *l = curlwp; 559 struct proc *p; 560 int error; 561 562 if (!l) { 563 return EFAULT; 564 } 565 566 p = l->l_proc; 567 568 /* 569 * Stolen from physio(): 570 */ 571 PHOLD(l); 572 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); 573 if (error) { 574 PRELE(l); 575 return EFAULT; 576 } 577 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 578 VM_PROT_READ | VM_PROT_WRITE); 579 580 memcpy(up, kp, len); 581 vunmaprange((vaddr_t)up, len); 582 uvm_vsunlock(p, udaddr, len); 583 PRELE(l); 584 585 return 0; 586} 587 588/* 589 * kcopy(const void *src, void *dst, size_t len); 590 * 591 * Copy len bytes from src to dst, aborting if we encounter a fatal 592 * page fault. 593 * 594 * kcopy() _must_ save and restore the old fault handler since it is 595 * called by uiomove(), which may be in the path of servicing a non-fatal 596 * page fault. 597 */ 598int 599kcopy(const void *src, void *dst, size_t len) 600{ 601 struct faultbuf env, *oldfault; 602 603 oldfault = curpcb->pcb_onfault; 604 if (setfault(&env)) { 605 curpcb->pcb_onfault = oldfault; 606 return EFAULT; 607 } 608 609 memcpy(dst, src, len); 610 611 curpcb->pcb_onfault = oldfault; 612 return 0; 613} 614 615int 616badaddr(void *addr, size_t size) 617{ 618 619 return badaddr_read(addr, size, NULL); 620} 621 622int 623badaddr_read(void *addr, size_t size, int *rptr) 624{ 625 struct faultbuf env; 626 int x; 627 628 /* Get rid of any stale machine checks that have been waiting. */ 629 __asm volatile ("sync; isync"); 630 631 if (setfault(&env)) { 632 curpcb->pcb_onfault = 0; 633 __asm volatile ("sync"); 634 return 1; 635 } 636 637 __asm volatile ("sync"); 638 639 switch (size) { 640 case 1: 641 x = *(volatile int8_t *)addr; 642 break; 643 case 2: 644 x = *(volatile int16_t *)addr; 645 break; 646 case 4: 647 x = *(volatile int32_t *)addr; 648 break; 649 default: 650 panic("badaddr: invalid size (%d)", size); 651 } 652 653 /* Make sure we took the machine check, if we caused one. */ 654 __asm volatile ("sync; isync"); 655 656 curpcb->pcb_onfault = 0; 657 __asm volatile ("sync"); /* To be sure. */ 658 659 /* Use the value to avoid reorder. */ 660 if (rptr) 661 *rptr = x; 662 663 return 0; 664} 665 666/* 667 * For now, this only deals with the particular unaligned access case 668 * that gcc tends to generate. Eventually it should handle all of the 669 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 670 */ 671 672static int 673fix_unaligned(struct lwp *l, struct trapframe *frame) 674{ 675 676 return -1; 677} 678 679/* 680 * Start a new LWP 681 */ 682void 683startlwp(arg) 684 void *arg; 685{ 686 int err; 687 ucontext_t *uc = arg; 688 struct lwp *l = curlwp; 689 690 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 691#if DIAGNOSTIC 692 if (err) { 693 printf("Error %d from cpu_setmcontext.", err); 694 } 695#endif 696 pool_put(&lwp_uc_pool, uc); 697 698 upcallret(l); 699} 700 701/* 702 * XXX This is a terrible name. 703 */ 704void 705upcallret(l) 706 struct lwp *l; 707{ 708 709 /* Invoke MI userret code */ 710 mi_userret(l); 711 712 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 713} 714