trap.c revision 1.17
1 /* $NetBSD: trap.c,v 1.17 2003/09/25 18:42:18 matt 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 1.17 2003/09/25 18:42:18 matt Exp $"); 71 72 #include "opt_altivec.h" 73 #include "opt_ddb.h" 74 #include "opt_ktrace.h" 75 #include "opt_systrace.h" 76 #include "opt_syscall_debug.h" 77 78 #include <sys/param.h> 79 #include <sys/proc.h> 80 #include <sys/reboot.h> 81 #include <sys/syscall.h> 82 #include <sys/systm.h> 83 #include <sys/user.h> 84 #ifdef KTRACE 85 #include <sys/ktrace.h> 86 #endif 87 #include <sys/pool.h> 88 #include <sys/sa.h> 89 #include <sys/savar.h> 90 #ifdef SYSTRACE 91 #include <sys/systrace.h> 92 #endif 93 94 #include <uvm/uvm_extern.h> 95 96 #include <dev/cons.h> 97 98 #include <machine/cpu.h> 99 #include <machine/db_machdep.h> 100 #include <machine/fpu.h> 101 #include <machine/frame.h> 102 #include <machine/pcb.h> 103 #include <machine/psl.h> 104 #include <machine/trap.h> 105 106 #include <powerpc/spr.h> 107 #include <powerpc/ibm4xx/pmap.h> 108 #include <powerpc/ibm4xx/tlb.h> 109 #include <powerpc/fpu/fpu_extern.h> 110 111 /* These definitions should probably be somewhere else XXX */ 112 #define FIRSTARG 3 /* first argument is in reg 3 */ 113 #define NARGREG 8 /* 8 args are in registers */ 114 #define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */ 115 116 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 117 118 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 119 /* Why are these not defined in a header? */ 120 int badaddr __P((void *, size_t)); 121 int badaddr_read __P((void *, size_t, int *)); 122 int ctx_setup __P((int, int)); 123 124 #ifdef DEBUG 125 #define TDB_ALL 0x1 126 int trapdebug = /* TDB_ALL */ 0; 127 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y 128 #else 129 #define DBPRINTF(x, y) 130 #endif 131 132 void 133 trap(struct trapframe *frame) 134 { 135 struct lwp *l = curlwp; 136 struct proc *p = l ? l->l_proc : NULL; 137 int type = frame->exc; 138 int ftype, rv; 139 140 KASSERT(l == 0 || (l->l_stat == LSONPROC)); 141 142 if (frame->srr1 & PSL_PR) 143 type |= EXC_USER; 144 145 ftype = VM_PROT_READ; 146 147 DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n", 148 type, frame->srr0, frame, &frame)); 149 150 switch (type) { 151 case EXC_DEBUG|EXC_USER: 152 { 153 int srr2, srr3; 154 155 __asm __volatile("mfspr %0,0x3f0" : 156 "=r" (rv), "=r" (srr2), "=r" (srr3) :); 157 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, 158 srr3); 159 /* XXX fall through or break here?! */ 160 } 161 /* 162 * DEBUG intr -- probably single-step. 163 */ 164 case EXC_TRC|EXC_USER: 165 frame->srr1 &= ~PSL_SE; 166 memset(&ksi, 0, sizeof(ksi)); 167 ksi.ksi_signo = SIGTRAP; 168 ksi.ksi_trap = EXC_TRC; 169 ksi.ksi_addr = (void *)frame->srr0; 170 KERNEL_PROC_LOCK(l); 171 trapsignal(l, &ksi); 172 KERNEL_PROC_UNLOCK(l); 173 break; 174 175 /* 176 * If we could not find and install appropriate TLB entry, fall through. 177 */ 178 179 case EXC_DSI: 180 /* FALLTHROUGH */ 181 case EXC_DTMISS: 182 { 183 struct vm_map *map; 184 vaddr_t va; 185 struct faultbuf *fb = NULL; 186 187 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE); 188 va = frame->dar; 189 if (frame->tf_xtra[TF_PID] == KERNEL_PID) { 190 map = kernel_map; 191 } else { 192 map = &p->p_vmspace->vm_map; 193 if (l->l_flag & L_SA) { 194 KDASSERT(p != NULL && p->p_sa != NULL); 195 p->p_sa->sa_vp_faultaddr = va; 196 l->l_flag |= L_SA_PAGEFAULT; 197 } 198 } 199 200 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 201 ftype = VM_PROT_WRITE; 202 203 DBPRINTF(TDB_ALL, 204 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 205 frame->srr0, 206 (ftype & VM_PROT_WRITE) ? "write" : "read", 207 (void *)va, frame->tf_xtra[TF_ESR])); 208 rv = uvm_fault(map, trunc_page(va), 0, ftype); 209 KERNEL_UNLOCK(); 210 if (map != kernel_map) 211 l->l_flag &= ~L_SA_PAGEFAULT; 212 if (rv == 0) 213 goto done; 214 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 215 frame->tf_xtra[TF_PID] = KERNEL_PID; 216 frame->srr0 = fb->fb_pc; 217 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 218 frame->fixreg[1] = fb->fb_sp; 219 frame->fixreg[2] = fb->fb_r2; 220 frame->fixreg[3] = 1; /* Return TRUE */ 221 frame->cr = fb->fb_cr; 222 memcpy(&frame->fixreg[13], fb->fb_fixreg, 223 sizeof(fb->fb_fixreg)); 224 goto done; 225 } 226 } 227 goto brain_damage; 228 229 case EXC_DSI|EXC_USER: 230 /* FALLTHROUGH */ 231 case EXC_DTMISS|EXC_USER: 232 KERNEL_PROC_LOCK(l); 233 234 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 235 ftype = VM_PROT_WRITE; 236 237 DBPRINTF(TDB_ALL, 238 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 239 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 240 frame->dar, frame->tf_xtra[TF_ESR])); 241 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 242 if (l->l_flag & L_SA) { 243 KDASSERT(p != NULL && p->p_sa != NULL); 244 p->p_sa->sa_vp_faultaddr = (vaddr_t)frame->dar; 245 l->l_flag |= L_SA_PAGEFAULT; 246 } 247 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 248 0, ftype); 249 if (rv == 0) { 250 l->l_flag &= ~L_SA_PAGEFAULT; 251 KERNEL_PROC_UNLOCK(l); 252 break; 253 } 254 memset(&ksi, 0, sizeof(ksi)); 255 ksi.ksi_signo = SIGSEGV; 256 ksi.ksi_trap = EXC_DSI; 257 ksi.ksi_addr = (void *)frame->dar; 258 if (rv == ENOMEM) { 259 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 260 "out of swap\n", 261 p->p_pid, p->p_comm, l->l_lid, 262 p->p_cred && p->p_ucred ? 263 p->p_ucred->cr_uid : -1); 264 ksi.ksi_signo = SIGKILL; 265 } 266 trapsignal(l, &ksi); 267 l->l_flag &= ~L_SA_PAGEFAULT; 268 KERNEL_PROC_UNLOCK(l); 269 break; 270 271 case EXC_ITMISS|EXC_USER: 272 case EXC_ISI|EXC_USER: 273 KERNEL_PROC_LOCK(l); 274 if (l->l_flag & L_SA) { 275 KDASSERT(p != NULL && p->p_sa != NULL); 276 p->p_sa->sa_vp_faultaddr = (vaddr_t)frame->srr0; 277 l->l_flag |= L_SA_PAGEFAULT; 278 } 279 ftype = VM_PROT_EXECUTE; 280 DBPRINTF(TDB_ALL, 281 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 282 frame->srr0, frame)); 283 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 284 0, ftype); 285 if (rv == 0) { 286 l->l_flag &= ~L_SA_PAGEFAULT; 287 KERNEL_PROC_UNLOCK(l); 288 break; 289 } 290 memset(&ksi, 0, sizeof(ksi)); 291 ksi.ksi_signo = SIGSEGV; 292 ksi.ksi_trap = EXC_ISI; 293 ksi.ksi_addr = (void *)frame->srr0; 294 trapsignal(l, &ksi); 295 l->l_flag &= ~L_SA_PAGEFAULT; 296 KERNEL_PROC_UNLOCK(l); 297 break; 298 299 case EXC_AST|EXC_USER: 300 curcpu()->ci_astpending = 0; /* we are about to do it */ 301 KERNEL_PROC_LOCK(l); 302 uvmexp.softs++; 303 if (p->p_flag & P_OWEUPC) { 304 p->p_flag &= ~P_OWEUPC; 305 ADDUPROF(p); 306 } 307 /* Check whether we are being preempted. */ 308 if (curcpu()->ci_want_resched) 309 preempt(0); 310 KERNEL_PROC_UNLOCK(l); 311 break; 312 313 314 case EXC_ALI|EXC_USER: 315 KERNEL_PROC_LOCK(l); 316 if (fix_unaligned(l, frame) != 0) { 317 memset(&ksi, 0, sizeof(ksi)); 318 ksi.ksi_signo = SIGBUS; 319 ksi.ksi_trap = EXC_ALI; 320 ksi.ksi_addr = (void *)frame->dar; 321 trapsignal(l, &ksi); 322 } else 323 frame->srr0 += 4; 324 KERNEL_PROC_UNLOCK(l); 325 break; 326 327 case EXC_PGM|EXC_USER: 328 /* 329 * Illegal insn: 330 * 331 * let's try to see if it's FPU and can be emulated. 332 */ 333 uvmexp.traps ++; 334 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 335 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 336 sizeof l->l_addr->u_pcb.pcb_fpu); 337 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 338 } 339 340 if ((rv = fpu_emulate(frame, 341 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 342 memset(&ksi, 0, sizeof(ksi)); 343 ksi.ksi_signo = rv; 344 ksi.ksi_trap = EXC_PGM; 345 ksi.ksi_addr = (void *)frame->srr0; 346 KERNEL_PROC_LOCK(l); 347 trapsignal(l, &ksi); 348 KERNEL_PROC_UNLOCK(l); 349 } 350 break; 351 352 case EXC_MCHK: 353 { 354 struct faultbuf *fb; 355 356 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 357 frame->tf_xtra[TF_PID] = KERNEL_PID; 358 frame->srr0 = fb->fb_pc; 359 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 360 frame->fixreg[1] = fb->fb_sp; 361 frame->fixreg[2] = fb->fb_r2; 362 frame->fixreg[3] = 1; /* Return TRUE */ 363 frame->cr = fb->fb_cr; 364 memcpy(&frame->fixreg[13], fb->fb_fixreg, 365 sizeof(fb->fb_fixreg)); 366 goto done; 367 } 368 } 369 goto brain_damage; 370 default: 371 brain_damage: 372 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 373 #ifdef DDB 374 if (kdb_trap(type, frame)) 375 goto done; 376 #endif 377 #ifdef TRAP_PANICWAIT 378 printf("Press a key to panic.\n"); 379 cngetc(); 380 #endif 381 panic("trap"); 382 } 383 384 /* Take pending signals. */ 385 { 386 int sig; 387 388 while ((sig = CURSIG(l)) != 0) 389 postsig(sig); 390 } 391 392 /* Invoke per-process kernel-exit handling, if any */ 393 if (p->p_userret) 394 (p->p_userret)(l, p->p_userret_arg); 395 396 /* Invoke any pending upcalls */ 397 while (l->l_flag & L_SA_UPCALL) 398 sa_upcall_userret(l); 399 400 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 401 done: 402 return; 403 } 404 405 int 406 ctx_setup(int ctx, int srr1) 407 { 408 volatile struct pmap *pm; 409 410 /* Update PID if we're returning to user mode. */ 411 if (srr1 & PSL_PR) { 412 pm = curproc->p_vmspace->vm_map.pmap; 413 if (!pm->pm_ctx) { 414 ctx_alloc((struct pmap *)pm); 415 } 416 ctx = pm->pm_ctx; 417 if (srr1 & PSL_SE) { 418 int dbreg, mask = 0x48000000; 419 /* 420 * Set the Internal Debug and 421 * Instruction Completion bits of 422 * the DBCR0 register. 423 * 424 * XXX this is also used by jtag debuggers... 425 */ 426 __asm __volatile("mfspr %0,0x3f2;" 427 "or %0,%0,%1;" 428 "mtspr 0x3f2,%0;" : 429 "=&r" (dbreg) : "r" (mask)); 430 } 431 } 432 else if (!ctx) { 433 ctx = KERNEL_PID; 434 } 435 return (ctx); 436 } 437 438 /* 439 * Used by copyin()/copyout() 440 */ 441 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 442 extern void vunmaprange __P((vaddr_t, vsize_t)); 443 static int bigcopyin __P((const void *, void *, size_t )); 444 static int bigcopyout __P((const void *, void *, size_t )); 445 446 int 447 copyin(const void *udaddr, void *kaddr, size_t len) 448 { 449 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 450 int msr, pid, tmp, ctx; 451 struct faultbuf env; 452 453 /* For bigger buffers use the faster copy */ 454 if (len > 256) return (bigcopyin(udaddr, kaddr, len)); 455 456 if (setfault(&env)) { 457 curpcb->pcb_onfault = 0; 458 return EFAULT; 459 } 460 461 if (!(ctx = pm->pm_ctx)) { 462 /* No context -- assign it one */ 463 ctx_alloc(pm); 464 ctx = pm->pm_ctx; 465 } 466 467 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 468 "mfmsr %0;" /* Save MSR */ 469 "li %1,0x20; " 470 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 471 "mfpid %1;" /* Save old PID */ 472 "sync; isync;" 473 474 "1: bdz 2f;" /* while len */ 475 "mtpid %3; sync;" /* Load user ctx */ 476 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 477 "sync; isync;" 478 "mtpid %1;sync;" 479 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 480 "sync; isync;" 481 "b 1b;" /* repeat */ 482 483 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 484 "sync; isync;" 485 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 486 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 487 488 curpcb->pcb_onfault = 0; 489 return 0; 490 } 491 492 static int 493 bigcopyin(const void *udaddr, void *kaddr, size_t len) 494 { 495 const char *up; 496 char *kp = kaddr; 497 struct lwp *l = curlwp; 498 struct proc *p; 499 int error; 500 501 if (!l) { 502 return EFAULT; 503 } 504 505 p = l->l_proc; 506 507 /* 508 * Stolen from physio(): 509 */ 510 PHOLD(l); 511 error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ); 512 if (error) { 513 PRELE(l); 514 return EFAULT; 515 } 516 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 517 518 memcpy(kp, up, len); 519 vunmaprange((vaddr_t)up, len); 520 uvm_vsunlock(p, (caddr_t)udaddr, len); 521 PRELE(l); 522 523 return 0; 524 } 525 526 int 527 copyout(const void *kaddr, void *udaddr, size_t len) 528 { 529 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 530 int msr, pid, tmp, ctx; 531 struct faultbuf env; 532 533 /* For big copies use more efficient routine */ 534 if (len > 256) return (bigcopyout(kaddr, udaddr, len)); 535 536 if (setfault(&env)) { 537 curpcb->pcb_onfault = 0; 538 return EFAULT; 539 } 540 541 if (!(ctx = pm->pm_ctx)) { 542 /* No context -- assign it one */ 543 ctx_alloc(pm); 544 ctx = pm->pm_ctx; 545 } 546 547 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 548 "mfmsr %0;" /* Save MSR */ 549 "li %1,0x20; " 550 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 551 "mfpid %1;" /* Save old PID */ 552 "sync; isync;" 553 554 "1: bdz 2f;" /* while len */ 555 "mtpid %1;sync;" 556 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 557 "sync; isync;" 558 "mtpid %3; sync;" /* Load user ctx */ 559 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 560 "sync; isync;" 561 "b 1b;" /* repeat */ 562 563 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 564 "sync; isync;" 565 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 566 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 567 568 curpcb->pcb_onfault = 0; 569 return 0; 570 } 571 572 static int 573 bigcopyout(const void *kaddr, void *udaddr, size_t len) 574 { 575 char *up; 576 const char *kp = (char *)kaddr; 577 struct lwp *l = curlwp; 578 struct proc *p; 579 int error; 580 581 if (!l) { 582 return EFAULT; 583 } 584 585 p = l->l_proc; 586 587 /* 588 * Stolen from physio(): 589 */ 590 PHOLD(l); 591 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); 592 if (error) { 593 PRELE(l); 594 return EFAULT; 595 } 596 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 597 VM_PROT_READ | VM_PROT_WRITE); 598 599 memcpy(up, kp, len); 600 vunmaprange((vaddr_t)up, len); 601 uvm_vsunlock(p, udaddr, len); 602 PRELE(l); 603 604 return 0; 605 } 606 607 /* 608 * kcopy(const void *src, void *dst, size_t len); 609 * 610 * Copy len bytes from src to dst, aborting if we encounter a fatal 611 * page fault. 612 * 613 * kcopy() _must_ save and restore the old fault handler since it is 614 * called by uiomove(), which may be in the path of servicing a non-fatal 615 * page fault. 616 */ 617 int 618 kcopy(const void *src, void *dst, size_t len) 619 { 620 struct faultbuf env, *oldfault; 621 622 oldfault = curpcb->pcb_onfault; 623 if (setfault(&env)) { 624 curpcb->pcb_onfault = oldfault; 625 return EFAULT; 626 } 627 628 memcpy(dst, src, len); 629 630 curpcb->pcb_onfault = oldfault; 631 return 0; 632 } 633 634 int 635 badaddr(void *addr, size_t size) 636 { 637 638 return badaddr_read(addr, size, NULL); 639 } 640 641 int 642 badaddr_read(void *addr, size_t size, int *rptr) 643 { 644 struct faultbuf env; 645 int x; 646 647 /* Get rid of any stale machine checks that have been waiting. */ 648 __asm __volatile ("sync; isync"); 649 650 if (setfault(&env)) { 651 curpcb->pcb_onfault = 0; 652 __asm __volatile ("sync"); 653 return 1; 654 } 655 656 __asm __volatile ("sync"); 657 658 switch (size) { 659 case 1: 660 x = *(volatile int8_t *)addr; 661 break; 662 case 2: 663 x = *(volatile int16_t *)addr; 664 break; 665 case 4: 666 x = *(volatile int32_t *)addr; 667 break; 668 default: 669 panic("badaddr: invalid size (%d)", size); 670 } 671 672 /* Make sure we took the machine check, if we caused one. */ 673 __asm __volatile ("sync; isync"); 674 675 curpcb->pcb_onfault = 0; 676 __asm __volatile ("sync"); /* To be sure. */ 677 678 /* Use the value to avoid reorder. */ 679 if (rptr) 680 *rptr = x; 681 682 return 0; 683 } 684 685 /* 686 * For now, this only deals with the particular unaligned access case 687 * that gcc tends to generate. Eventually it should handle all of the 688 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 689 */ 690 691 static int 692 fix_unaligned(struct lwp *l, struct trapframe *frame) 693 { 694 695 return -1; 696 } 697 698 /* 699 * Start a new LWP 700 */ 701 void 702 startlwp(arg) 703 void *arg; 704 { 705 int err; 706 ucontext_t *uc = arg; 707 struct lwp *l = curlwp; 708 709 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 710 #if DIAGNOSTIC 711 if (err) { 712 printf("Error %d from cpu_setmcontext.", err); 713 } 714 #endif 715 pool_put(&lwp_uc_pool, uc); 716 717 upcallret(l); 718 } 719 720 /* 721 * XXX This is a terrible name. 722 */ 723 void 724 upcallret(l) 725 struct lwp *l; 726 { 727 int sig; 728 729 /* Take pending signals. */ 730 while ((sig = CURSIG(l)) != 0) 731 postsig(sig); 732 733 /* Invoke per-process kernel-exit handling, if any */ 734 if (l->l_proc->p_userret) 735 (l->l_proc->p_userret)(l, l->l_proc->p_userret_arg); 736 737 /* Invoke any pending upcalls */ 738 while (l->l_flag & L_SA_UPCALL) 739 sa_upcall_userret(l); 740 741 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 742 } 743
Indexes created Sun Sep 21 16:09:51 GMT 2025