trap.c revision 1.38
1 /* $NetBSD: trap.c,v 1.38 2007/02/09 21:55:10 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 1.38 2007/02/09 21:55:10 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) ((caddr_t)((int)(sp) + 8)) /* more args go here */ 106 107 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 108 109 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 110 /* Why are these not defined in a header? */ 111 int badaddr __P((void *, size_t)); 112 int badaddr_read __P((void *, size_t, int *)); 113 int ctx_setup __P((int, int)); 114 115 #ifdef DEBUG 116 #define TDB_ALL 0x1 117 int trapdebug = /* TDB_ALL */ 0; 118 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y 119 #else 120 #define DBPRINTF(x, y) 121 #endif 122 123 void 124 trap(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_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 } 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(); 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_PROC_LOCK(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_PROC_UNLOCK(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_PROC_UNLOCK(l); 249 break; 250 251 case EXC_ITMISS|EXC_USER: 252 case EXC_ISI|EXC_USER: 253 KERNEL_PROC_LOCK(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_PROC_UNLOCK(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_PROC_UNLOCK(l); 271 break; 272 273 case EXC_AST|EXC_USER: 274 curcpu()->ci_astpending = 0; /* we are about to do it */ 275 KERNEL_PROC_LOCK(l); 276 uvmexp.softs++; 277 if (p->p_flag & P_OWEUPC) { 278 p->p_flag &= ~P_OWEUPC; 279 ADDUPROF(p); 280 } 281 /* Check whether we are being preempted. */ 282 if (curcpu()->ci_want_resched) 283 preempt(); 284 KERNEL_PROC_UNLOCK(l); 285 break; 286 287 288 case EXC_ALI|EXC_USER: 289 KERNEL_PROC_LOCK(l); 290 if (fix_unaligned(l, frame) != 0) { 291 KSI_INIT_TRAP(&ksi); 292 ksi.ksi_signo = SIGBUS; 293 ksi.ksi_trap = EXC_ALI; 294 ksi.ksi_addr = (void *)frame->dar; 295 trapsignal(l, &ksi); 296 } else 297 frame->srr0 += 4; 298 KERNEL_PROC_UNLOCK(l); 299 break; 300 301 case EXC_PGM|EXC_USER: 302 /* 303 * Illegal insn: 304 * 305 * let's try to see if it's FPU and can be emulated. 306 */ 307 uvmexp.traps++; 308 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 309 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 310 sizeof l->l_addr->u_pcb.pcb_fpu); 311 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 312 } 313 314 if ((rv = fpu_emulate(frame, 315 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 316 KSI_INIT_TRAP(&ksi); 317 ksi.ksi_signo = rv; 318 ksi.ksi_trap = EXC_PGM; 319 ksi.ksi_addr = (void *)frame->srr0; 320 KERNEL_PROC_LOCK(l); 321 trapsignal(l, &ksi); 322 KERNEL_PROC_UNLOCK(l); 323 } 324 break; 325 326 case EXC_MCHK: 327 { 328 struct faultbuf *fb; 329 330 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 331 frame->tf_xtra[TF_PID] = KERNEL_PID; 332 frame->srr0 = fb->fb_pc; 333 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 334 frame->fixreg[1] = fb->fb_sp; 335 frame->fixreg[2] = fb->fb_r2; 336 frame->fixreg[3] = 1; /* Return TRUE */ 337 frame->cr = fb->fb_cr; 338 memcpy(&frame->fixreg[13], fb->fb_fixreg, 339 sizeof(fb->fb_fixreg)); 340 goto done; 341 } 342 } 343 goto brain_damage; 344 default: 345 brain_damage: 346 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 347 #ifdef DDB 348 if (kdb_trap(type, frame)) 349 goto done; 350 #endif 351 #ifdef TRAP_PANICWAIT 352 printf("Press a key to panic.\n"); 353 cngetc(); 354 #endif 355 panic("trap"); 356 } 357 358 /* Invoke MI userret code */ 359 mi_userret(l); 360 361 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 362 done: 363 return; 364 } 365 366 int 367 ctx_setup(int ctx, int srr1) 368 { 369 volatile struct pmap *pm; 370 371 /* Update PID if we're returning to user mode. */ 372 if (srr1 & PSL_PR) { 373 pm = curproc->p_vmspace->vm_map.pmap; 374 if (!pm->pm_ctx) { 375 ctx_alloc(__UNVOLATILE(pm)); 376 } 377 ctx = pm->pm_ctx; 378 if (srr1 & PSL_SE) { 379 int dbreg, mask = 0x48000000; 380 /* 381 * Set the Internal Debug and 382 * Instruction Completion bits of 383 * the DBCR0 register. 384 * 385 * XXX this is also used by jtag debuggers... 386 */ 387 __asm volatile("mfspr %0,0x3f2;" 388 "or %0,%0,%1;" 389 "mtspr 0x3f2,%0;" : 390 "=&r" (dbreg) : "r" (mask)); 391 } 392 } 393 else if (!ctx) { 394 ctx = KERNEL_PID; 395 } 396 return (ctx); 397 } 398 399 /* 400 * Used by copyin()/copyout() 401 */ 402 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 403 extern void vunmaprange __P((vaddr_t, vsize_t)); 404 static int bigcopyin __P((const void *, void *, size_t )); 405 static int bigcopyout __P((const void *, void *, size_t )); 406 407 int 408 copyin(const void *udaddr, void *kaddr, size_t len) 409 { 410 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 411 int msr, pid, tmp, ctx; 412 struct faultbuf env; 413 414 /* For bigger buffers use the faster copy */ 415 if (len > 256) 416 return (bigcopyin(udaddr, kaddr, len)); 417 418 if (setfault(&env)) { 419 curpcb->pcb_onfault = 0; 420 return EFAULT; 421 } 422 423 if (!(ctx = pm->pm_ctx)) { 424 /* No context -- assign it one */ 425 ctx_alloc(pm); 426 ctx = pm->pm_ctx; 427 } 428 429 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 430 "mfmsr %0;" /* Save MSR */ 431 "li %1,0x20; " 432 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 433 "mfpid %1;" /* Save old PID */ 434 "sync; isync;" 435 436 "1: bdz 2f;" /* while len */ 437 "mtpid %3; sync;" /* Load user ctx */ 438 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 439 "sync; isync;" 440 "mtpid %1;sync;" 441 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 442 "sync; isync;" 443 "b 1b;" /* repeat */ 444 445 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 446 "sync; isync;" 447 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 448 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len)); 449 450 curpcb->pcb_onfault = 0; 451 return 0; 452 } 453 454 static int 455 bigcopyin(const void *udaddr, void *kaddr, size_t len) 456 { 457 const char *up; 458 char *kp = kaddr; 459 struct lwp *l = curlwp; 460 struct proc *p; 461 int error; 462 463 if (!l) { 464 return EFAULT; 465 } 466 467 p = l->l_proc; 468 469 /* 470 * Stolen from physio(): 471 */ 472 PHOLD(l); 473 error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ); 474 if (error) { 475 PRELE(l); 476 return EFAULT; 477 } 478 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 479 480 memcpy(kp, up, len); 481 vunmaprange((vaddr_t)up, len); 482 uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len); 483 PRELE(l); 484 485 return 0; 486 } 487 488 int 489 copyout(const void *kaddr, void *udaddr, size_t len) 490 { 491 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 492 int msr, pid, tmp, ctx; 493 struct faultbuf env; 494 495 /* For big copies use more efficient routine */ 496 if (len > 256) 497 return (bigcopyout(kaddr, udaddr, len)); 498 499 if (setfault(&env)) { 500 curpcb->pcb_onfault = 0; 501 return EFAULT; 502 } 503 504 if (!(ctx = pm->pm_ctx)) { 505 /* No context -- assign it one */ 506 ctx_alloc(pm); 507 ctx = pm->pm_ctx; 508 } 509 510 __asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 511 "mfmsr %0;" /* Save MSR */ 512 "li %1,0x20; " 513 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 514 "mfpid %1;" /* Save old PID */ 515 "sync; isync;" 516 517 "1: bdz 2f;" /* while len */ 518 "mtpid %1;sync;" 519 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 520 "sync; isync;" 521 "mtpid %3; sync;" /* Load user ctx */ 522 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 523 "sync; isync;" 524 "b 1b;" /* repeat */ 525 526 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 527 "sync; isync;" 528 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 529 : "r" (ctx), "b" (udaddr), "b" (kaddr), "b" (len)); 530 531 curpcb->pcb_onfault = 0; 532 return 0; 533 } 534 535 static int 536 bigcopyout(const void *kaddr, void *udaddr, size_t len) 537 { 538 char *up; 539 const char *kp = (const char *)kaddr; 540 struct lwp *l = curlwp; 541 struct proc *p; 542 int error; 543 544 if (!l) { 545 return EFAULT; 546 } 547 548 p = l->l_proc; 549 550 /* 551 * Stolen from physio(): 552 */ 553 PHOLD(l); 554 error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE); 555 if (error) { 556 PRELE(l); 557 return EFAULT; 558 } 559 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 560 VM_PROT_READ | VM_PROT_WRITE); 561 562 memcpy(up, kp, len); 563 vunmaprange((vaddr_t)up, len); 564 uvm_vsunlock(p->p_vmspace, udaddr, len); 565 PRELE(l); 566 567 return 0; 568 } 569 570 /* 571 * kcopy(const void *src, void *dst, size_t len); 572 * 573 * Copy len bytes from src to dst, aborting if we encounter a fatal 574 * page fault. 575 * 576 * kcopy() _must_ save and restore the old fault handler since it is 577 * called by uiomove(), which may be in the path of servicing a non-fatal 578 * page fault. 579 */ 580 int 581 kcopy(const void *src, void *dst, size_t len) 582 { 583 struct faultbuf env, *oldfault; 584 585 oldfault = curpcb->pcb_onfault; 586 if (setfault(&env)) { 587 curpcb->pcb_onfault = oldfault; 588 return EFAULT; 589 } 590 591 memcpy(dst, src, len); 592 593 curpcb->pcb_onfault = oldfault; 594 return 0; 595 } 596 597 int 598 badaddr(void *addr, size_t size) 599 { 600 601 return badaddr_read(addr, size, NULL); 602 } 603 604 int 605 badaddr_read(void *addr, size_t size, int *rptr) 606 { 607 struct faultbuf env; 608 int x; 609 610 /* Get rid of any stale machine checks that have been waiting. */ 611 __asm volatile ("sync; isync"); 612 613 if (setfault(&env)) { 614 curpcb->pcb_onfault = 0; 615 __asm volatile ("sync"); 616 return 1; 617 } 618 619 __asm volatile ("sync"); 620 621 switch (size) { 622 case 1: 623 x = *(volatile int8_t *)addr; 624 break; 625 case 2: 626 x = *(volatile int16_t *)addr; 627 break; 628 case 4: 629 x = *(volatile int32_t *)addr; 630 break; 631 default: 632 panic("badaddr: invalid size (%d)", size); 633 } 634 635 /* Make sure we took the machine check, if we caused one. */ 636 __asm volatile ("sync; isync"); 637 638 curpcb->pcb_onfault = 0; 639 __asm volatile ("sync"); /* To be sure. */ 640 641 /* Use the value to avoid reorder. */ 642 if (rptr) 643 *rptr = x; 644 645 return 0; 646 } 647 648 /* 649 * For now, this only deals with the particular unaligned access case 650 * that gcc tends to generate. Eventually it should handle all of the 651 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 652 */ 653 654 static int 655 fix_unaligned(struct lwp *l, struct trapframe *frame) 656 { 657 658 return -1; 659 } 660 661 /* 662 * Start a new LWP 663 */ 664 void 665 startlwp(arg) 666 void *arg; 667 { 668 int err; 669 ucontext_t *uc = arg; 670 struct lwp *l = curlwp; 671 672 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 673 #if DIAGNOSTIC 674 if (err) { 675 printf("Error %d from cpu_setmcontext.", err); 676 } 677 #endif 678 pool_put(&lwp_uc_pool, uc); 679 680 /* Invoke MI userret code */ 681 mi_userret(l); 682 683 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 684 } 685
Indexes created Tue Sep 23 07:09:52 GMT 2025