trap.c revision 1.43
1/* $NetBSD: trap.c,v 1.43 2007/07/09 20:52:25 ad 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 1.43 2007/07/09 20:52:25 ad Exp $"); 71 72#include "opt_altivec.h" 73#include "opt_ddb.h" 74 75#include <sys/param.h> 76#include <sys/proc.h> 77#include <sys/reboot.h> 78#include <sys/syscall.h> 79#include <sys/systm.h> 80#include <sys/user.h> 81#include <sys/pool.h> 82#include <sys/userret.h> 83#include <sys/kauth.h> 84 85#include <uvm/uvm_extern.h> 86 87#include <dev/cons.h> 88 89#include <machine/cpu.h> 90#include <machine/db_machdep.h> 91#include <machine/fpu.h> 92#include <machine/frame.h> 93#include <machine/pcb.h> 94#include <machine/psl.h> 95#include <machine/trap.h> 96 97#include <powerpc/spr.h> 98#include <powerpc/ibm4xx/pmap.h> 99#include <powerpc/ibm4xx/tlb.h> 100#include <powerpc/fpu/fpu_extern.h> 101 102/* These definitions should probably be somewhere else XXX */ 103#define FIRSTARG 3 /* first argument is in reg 3 */ 104#define NARGREG 8 /* 8 args are in registers */ 105#define MOREARGS(sp) ((void *)((int)(sp) + 8)) /* more args go here */ 106 107static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 108 109void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 110/* Why are these not defined in a header? */ 111int badaddr __P((void *, size_t)); 112int badaddr_read __P((void *, size_t, int *)); 113int ctx_setup __P((int, int)); 114 115#ifdef DEBUG 116#define TDB_ALL 0x1 117int trapdebug = /* TDB_ALL */ 0; 118#define DBPRINTF(x, y) if (trapdebug & (x)) printf y 119#else 120#define DBPRINTF(x, y) 121#endif 122 123void 124trap(struct trapframe *frame) 125{ 126 struct lwp *l = curlwp; 127 struct proc *p = l ? l->l_proc : NULL; 128 int type = frame->exc; 129 int ftype, rv; 130 ksiginfo_t ksi; 131 132 KASSERT(l == 0 || (l->l_stat == LSONPROC)); 133 134 if (frame->srr1 & PSL_PR) { 135 LWP_CACHE_CREDS(l, p); 136 type |= EXC_USER; 137 } 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_LOCK(1, l); 165 trapsignal(l, &ksi); 166 KERNEL_UNLOCK_LAST(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(1, NULL); 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 } 188 189 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 190 ftype = VM_PROT_WRITE; 191 192 DBPRINTF(TDB_ALL, 193 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 194 frame->srr0, 195 (ftype & VM_PROT_WRITE) ? "write" : "read", 196 (void *)va, frame->tf_xtra[TF_ESR])); 197 rv = uvm_fault(map, trunc_page(va), ftype); 198 KERNEL_UNLOCK_ONE(NULL); 199 if (rv == 0) 200 goto done; 201 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 202 frame->tf_xtra[TF_PID] = KERNEL_PID; 203 frame->srr0 = fb->fb_pc; 204 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 205 frame->fixreg[1] = fb->fb_sp; 206 frame->fixreg[2] = fb->fb_r2; 207 frame->fixreg[3] = 1; /* Return TRUE */ 208 frame->cr = fb->fb_cr; 209 memcpy(&frame->fixreg[13], fb->fb_fixreg, 210 sizeof(fb->fb_fixreg)); 211 goto done; 212 } 213 } 214 goto brain_damage; 215 216 case EXC_DSI|EXC_USER: 217 /* FALLTHROUGH */ 218 case EXC_DTMISS|EXC_USER: 219 KERNEL_LOCK(1, l); 220 221 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 222 ftype = VM_PROT_WRITE; 223 224 DBPRINTF(TDB_ALL, 225 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 226 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 227 frame->dar, frame->tf_xtra[TF_ESR])); 228 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 229 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 230 ftype); 231 if (rv == 0) { 232 KERNEL_UNLOCK_LAST(l); 233 break; 234 } 235 KSI_INIT_TRAP(&ksi); 236 ksi.ksi_signo = SIGSEGV; 237 ksi.ksi_trap = EXC_DSI; 238 ksi.ksi_addr = (void *)frame->dar; 239 if (rv == ENOMEM) { 240 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 241 "out of swap\n", 242 p->p_pid, p->p_comm, l->l_lid, 243 l->l_cred ? 244 kauth_cred_geteuid(l->l_cred) : -1); 245 ksi.ksi_signo = SIGKILL; 246 } 247 trapsignal(l, &ksi); 248 KERNEL_UNLOCK_LAST(l); 249 break; 250 251 case EXC_ITMISS|EXC_USER: 252 case EXC_ISI|EXC_USER: 253 KERNEL_LOCK(1, l); 254 ftype = VM_PROT_EXECUTE; 255 DBPRINTF(TDB_ALL, 256 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 257 frame->srr0, frame)); 258 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 259 ftype); 260 if (rv == 0) { 261 KERNEL_UNLOCK_LAST(l); 262 break; 263 } 264 KSI_INIT_TRAP(&ksi); 265 ksi.ksi_signo = SIGSEGV; 266 ksi.ksi_trap = EXC_ISI; 267 ksi.ksi_addr = (void *)frame->srr0; 268 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR); 269 trapsignal(l, &ksi); 270 KERNEL_UNLOCK_LAST(l); 271 break; 272 273 case EXC_AST|EXC_USER: 274 curcpu()->ci_astpending = 0; /* we are about to do it */ 275 uvmexp.softs++; 276 if (l->l_pflag & LP_OWEUPC) { 277 l->l_pflag &= ~LP_OWEUPC; 278 ADDUPROF(l); 279 } 280 /* Check whether we are being preempted. */ 281 if (curcpu()->ci_want_resched) 282 preempt(); 283 break; 284 285 286 case EXC_ALI|EXC_USER: 287 KERNEL_LOCK(1, l); 288 if (fix_unaligned(l, frame) != 0) { 289 KSI_INIT_TRAP(&ksi); 290 ksi.ksi_signo = SIGBUS; 291 ksi.ksi_trap = EXC_ALI; 292 ksi.ksi_addr = (void *)frame->dar; 293 trapsignal(l, &ksi); 294 } else 295 frame->srr0 += 4; 296 KERNEL_UNLOCK_LAST(l); 297 break; 298 299 case EXC_PGM|EXC_USER: 300 /* 301 * Illegal insn: 302 * 303 * let's try to see if it's FPU and can be emulated. 304 */ 305 uvmexp.traps++; 306 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 307 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 308 sizeof l->l_addr->u_pcb.pcb_fpu); 309 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 310 } 311 312 if ((rv = fpu_emulate(frame, 313 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 314 KSI_INIT_TRAP(&ksi); 315 ksi.ksi_signo = rv; 316 ksi.ksi_trap = EXC_PGM; 317 ksi.ksi_addr = (void *)frame->srr0; 318 KERNEL_LOCK(1, l); 319 trapsignal(l, &ksi); 320 KERNEL_UNLOCK_LAST(l); 321 } 322 break; 323 324 case EXC_MCHK: 325 { 326 struct faultbuf *fb; 327 328 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 329 frame->tf_xtra[TF_PID] = KERNEL_PID; 330 frame->srr0 = fb->fb_pc; 331 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 332 frame->fixreg[1] = fb->fb_sp; 333 frame->fixreg[2] = fb->fb_r2; 334 frame->fixreg[3] = 1; /* Return TRUE */ 335 frame->cr = fb->fb_cr; 336 memcpy(&frame->fixreg[13], fb->fb_fixreg, 337 sizeof(fb->fb_fixreg)); 338 goto done; 339 } 340 } 341 goto brain_damage; 342 default: 343 brain_damage: 344 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 345#ifdef DDB 346 if (kdb_trap(type, frame)) 347 goto done; 348#endif 349#ifdef TRAP_PANICWAIT 350 printf("Press a key to panic.\n"); 351 cngetc(); 352#endif 353 panic("trap"); 354 } 355 356 /* Invoke MI userret code */ 357 mi_userret(l); 358 359 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 360 done: 361 return; 362} 363 364int 365ctx_setup(int ctx, int srr1) 366{ 367 volatile struct pmap *pm; 368 369 /* Update PID if we're returning to user mode. */ 370 if (srr1 & PSL_PR) { 371 pm = curproc->p_vmspace->vm_map.pmap; 372 if (!pm->pm_ctx) { 373 ctx_alloc(__UNVOLATILE(pm)); 374 } 375 ctx = pm->pm_ctx; 376 if (srr1 & PSL_SE) { 377 int dbreg, mask = 0x48000000; 378 /* 379 * Set the Internal Debug and 380 * Instruction Completion bits of 381 * the DBCR0 register. 382 * 383 * XXX this is also used by jtag debuggers... 384 */ 385 __asm volatile("mfspr %0,0x3f2;" 386 "or %0,%0,%1;" 387 "mtspr 0x3f2,%0;" : 388 "=&r" (dbreg) : "r" (mask)); 389 } 390 } 391 else if (!ctx) { 392 ctx = KERNEL_PID; 393 } 394 return (ctx); 395} 396 397/* 398 * Used by copyin()/copyout() 399 */ 400extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 401extern void vunmaprange __P((vaddr_t, vsize_t)); 402static int bigcopyin __P((const void *, void *, size_t )); 403static int bigcopyout __P((const void *, void *, size_t )); 404 405int 406copyin(const void *udaddr, void *kaddr, size_t len) 407{ 408 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 409 int msr, pid, tmp, ctx; 410 struct faultbuf env; 411 412 /* For bigger buffers use the faster copy */ 413 if (len > 256) 414 return (bigcopyin(udaddr, kaddr, len)); 415 416 if (setfault(&env)) { 417 curpcb->pcb_onfault = 0; 418 return EFAULT; 419 } 420 421 if (!(ctx = pm->pm_ctx)) { 422 /* No context -- assign it one */ 423 ctx_alloc(pm); 424 ctx = pm->pm_ctx; 425 } 426 427 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 428 "mfmsr %0;" /* Save MSR */ 429 "li %1,0x20; " 430 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 431 "mfpid %1;" /* Save old PID */ 432 "sync; isync;" 433 434 "1: bdz 2f;" /* while len */ 435 "mtpid %3; sync;" /* Load user ctx */ 436 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 437 "sync; isync;" 438 "mtpid %1;sync;" 439 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 440 "sync; isync;" 441 "b 1b;" /* repeat */ 442 443 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 444 "sync; isync;" 445 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 446 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len)); 447 448 curpcb->pcb_onfault = 0; 449 return 0; 450} 451 452static int 453bigcopyin(const void *udaddr, void *kaddr, size_t len) 454{ 455 const char *up; 456 char *kp = kaddr; 457 struct lwp *l = curlwp; 458 struct proc *p; 459 int error; 460 461 if (!l) { 462 return EFAULT; 463 } 464 465 p = l->l_proc; 466 467 /* 468 * Stolen from physio(): 469 */ 470 uvm_lwp_hold(l); 471 error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ); 472 if (error) { 473 uvm_lwp_rele(l); 474 return EFAULT; 475 } 476 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 477 478 memcpy(kp, up, len); 479 vunmaprange((vaddr_t)up, len); 480 uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len); 481 uvm_lwp_rele(l); 482 483 return 0; 484} 485 486int 487copyout(const void *kaddr, void *udaddr, size_t len) 488{ 489 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 490 int msr, pid, tmp, ctx; 491 struct faultbuf env; 492 493 /* For big copies use more efficient routine */ 494 if (len > 256) 495 return (bigcopyout(kaddr, udaddr, len)); 496 497 if (setfault(&env)) { 498 curpcb->pcb_onfault = 0; 499 return EFAULT; 500 } 501 502 if (!(ctx = pm->pm_ctx)) { 503 /* No context -- assign it one */ 504 ctx_alloc(pm); 505 ctx = pm->pm_ctx; 506 } 507 508 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 509 "mfmsr %0;" /* Save MSR */ 510 "li %1,0x20; " 511 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 512 "mfpid %1;" /* Save old PID */ 513 "sync; isync;" 514 515 "1: bdz 2f;" /* while len */ 516 "mtpid %1;sync;" 517 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 518 "sync; isync;" 519 "mtpid %3; sync;" /* Load user ctx */ 520 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 521 "sync; isync;" 522 "b 1b;" /* repeat */ 523 524 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 525 "sync; isync;" 526 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 527 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len)); 528 529 curpcb->pcb_onfault = 0; 530 return 0; 531} 532 533static int 534bigcopyout(const void *kaddr, void *udaddr, size_t len) 535{ 536 char *up; 537 const char *kp = (const char *)kaddr; 538 struct lwp *l = curlwp; 539 struct proc *p; 540 int error; 541 542 if (!l) { 543 return EFAULT; 544 } 545 546 p = l->l_proc; 547 548 /* 549 * Stolen from physio(): 550 */ 551 uvm_lwp_hold(l); 552 error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE); 553 if (error) { 554 uvm_lwp_rele(l); 555 return EFAULT; 556 } 557 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 558 VM_PROT_READ | VM_PROT_WRITE); 559 560 memcpy(up, kp, len); 561 vunmaprange((vaddr_t)up, len); 562 uvm_vsunlock(p->p_vmspace, udaddr, len); 563 uvm_lwp_rele(l); 564 565 return 0; 566} 567 568/* 569 * kcopy(const void *src, void *dst, size_t len); 570 * 571 * Copy len bytes from src to dst, aborting if we encounter a fatal 572 * page fault. 573 * 574 * kcopy() _must_ save and restore the old fault handler since it is 575 * called by uiomove(), which may be in the path of servicing a non-fatal 576 * page fault. 577 */ 578int 579kcopy(const void *src, void *dst, size_t len) 580{ 581 struct faultbuf env, *oldfault; 582 583 oldfault = curpcb->pcb_onfault; 584 if (setfault(&env)) { 585 curpcb->pcb_onfault = oldfault; 586 return EFAULT; 587 } 588 589 memcpy(dst, src, len); 590 591 curpcb->pcb_onfault = oldfault; 592 return 0; 593} 594 595int 596badaddr(void *addr, size_t size) 597{ 598 599 return badaddr_read(addr, size, NULL); 600} 601 602int 603badaddr_read(void *addr, size_t size, int *rptr) 604{ 605 struct faultbuf env; 606 int x; 607 608 /* Get rid of any stale machine checks that have been waiting. */ 609 __asm volatile ("sync; isync"); 610 611 if (setfault(&env)) { 612 curpcb->pcb_onfault = 0; 613 __asm volatile ("sync"); 614 return 1; 615 } 616 617 __asm volatile ("sync"); 618 619 switch (size) { 620 case 1: 621 x = *(volatile int8_t *)addr; 622 break; 623 case 2: 624 x = *(volatile int16_t *)addr; 625 break; 626 case 4: 627 x = *(volatile int32_t *)addr; 628 break; 629 default: 630 panic("badaddr: invalid size (%d)", size); 631 } 632 633 /* Make sure we took the machine check, if we caused one. */ 634 __asm volatile ("sync; isync"); 635 636 curpcb->pcb_onfault = 0; 637 __asm volatile ("sync"); /* To be sure. */ 638 639 /* Use the value to avoid reorder. */ 640 if (rptr) 641 *rptr = x; 642 643 return 0; 644} 645 646/* 647 * For now, this only deals with the particular unaligned access case 648 * that gcc tends to generate. Eventually it should handle all of the 649 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 650 */ 651 652static int 653fix_unaligned(struct lwp *l, struct trapframe *frame) 654{ 655 656 return -1; 657} 658 659/* 660 * Start a new LWP 661 */ 662void 663startlwp(arg) 664 void *arg; 665{ 666 int err; 667 ucontext_t *uc = arg; 668 struct lwp *l = curlwp; 669 670 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 671#if DIAGNOSTIC 672 if (err) { 673 printf("Error %d from cpu_setmcontext.", err); 674 } 675#endif 676 pool_put(&lwp_uc_pool, uc); 677 678 /* Invoke MI userret code */ 679 mi_userret(l); 680 681 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 682} 683