trap.c revision 1.3.8.1
1 /* $NetBSD: trap.c,v 1.3.8.1 2002/07/15 00:33:10 gehenna 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 "opt_altivec.h" 70 #include "opt_ddb.h" 71 #include "opt_ktrace.h" 72 #include "opt_systrace.h" 73 #include "opt_syscall_debug.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 #ifdef KTRACE 82 #include <sys/ktrace.h> 83 #endif 84 #ifdef SYSTRACE 85 #include <sys/systrace.h> 86 #endif 87 88 #include <uvm/uvm_extern.h> 89 90 #include <dev/cons.h> 91 92 #include <machine/cpu.h> 93 #include <machine/db_machdep.h> 94 #include <machine/fpu.h> 95 #include <machine/frame.h> 96 #include <machine/pcb.h> 97 #include <machine/psl.h> 98 #include <machine/trap.h> 99 100 #include <powerpc/spr.h> 101 #include <powerpc/ibm4xx/pmap.h> 102 #include <powerpc/ibm4xx/tlb.h> 103 #include <powerpc/fpu/fpu_extern.h> 104 105 /* These definitions should probably be somewhere else XXX */ 106 #define FIRSTARG 3 /* first argument is in reg 3 */ 107 #define NARGREG 8 /* 8 args are in registers */ 108 #define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */ 109 110 #ifndef MULTIPROCESSOR 111 volatile int astpending; 112 volatile int want_resched; 113 #endif 114 115 void *syscall = NULL; /* XXX dummy symbol for emul_netbsd */ 116 117 static int fix_unaligned __P((struct proc *p, struct trapframe *frame)); 118 119 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 120 int setfault __P((faultbuf)); /* defined in locore.S */ 121 /* Why are these not defined in a header? */ 122 int badaddr __P((void *, size_t)); 123 int badaddr_read __P((void *, size_t, int *)); 124 int ctx_setup __P((int, int)); 125 126 #ifdef DEBUG 127 #define TDB_ALL 0x1 128 int trapdebug = /* TDB_ALL */ 0; 129 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y 130 #else 131 #define DBPRINTF(x, y) 132 #endif 133 134 void 135 trap(struct trapframe *frame) 136 { 137 struct proc *p = curproc; 138 int type = frame->exc; 139 int ftype, rv; 140 141 KASSERT(p == 0 || (p->p_stat == SONPROC)); 142 143 if (frame->srr1 & PSL_PR) 144 type |= EXC_USER; 145 146 ftype = VM_PROT_READ; 147 148 DBPRINTF(TDB_ALL, ("trap(%x) at %x from frame %p &frame %p\n", 149 type, frame->srr0, frame, &frame)); 150 151 switch (type) { 152 case EXC_DEBUG|EXC_USER: 153 { 154 int srr2, srr3; 155 __asm __volatile("mfspr %0,0x3f0" : "=r" (rv), "=r" (srr2), "=r" (srr3) :); 156 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, srr3); 157 } 158 /* 159 * DEBUG intr -- probably single-step. 160 */ 161 case EXC_TRC|EXC_USER: 162 KERNEL_PROC_LOCK(p); 163 frame->srr1 &= ~PSL_SE; 164 trapsignal(p, SIGTRAP, EXC_TRC); 165 KERNEL_PROC_UNLOCK(p); 166 break; 167 168 /* If we could not find and install appropriate TLB entry, fall through */ 169 170 case EXC_DSI: 171 /* FALLTHROUGH */ 172 case EXC_DTMISS: 173 { 174 struct vm_map *map; 175 vaddr_t va; 176 faultbuf *fb = NULL; 177 178 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE); 179 va = frame->dear; 180 if (frame->pid == KERNEL_PID) { 181 map = kernel_map; 182 } else { 183 map = &p->p_vmspace->vm_map; 184 } 185 186 if (frame->esr & (ESR_DST|ESR_DIZ)) 187 ftype = VM_PROT_WRITE; 188 189 DBPRINTF(TDB_ALL, ("trap(EXC_DSI) at %x %s fault on %p esr %x\n", 190 frame->srr0, (ftype&VM_PROT_WRITE) ? "write" : "read", (void *)va, frame->esr)); 191 rv = uvm_fault(map, trunc_page(va), 0, ftype); 192 KERNEL_UNLOCK(); 193 if (rv == 0) 194 goto done; 195 if ((fb = p->p_addr->u_pcb.pcb_onfault) != NULL) { 196 frame->pid = KERNEL_PID; 197 frame->srr0 = (*fb)[0]; 198 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 199 frame->fixreg[1] = (*fb)[1]; 200 frame->fixreg[2] = (*fb)[2]; 201 frame->fixreg[3] = 1; /* Return TRUE */ 202 frame->cr = (*fb)[3]; 203 memcpy(&frame->fixreg[13], &(*fb)[4], 204 19 * sizeof(register_t)); 205 goto done; 206 } 207 } 208 goto brain_damage; 209 210 case EXC_DSI|EXC_USER: 211 /* FALLTHROUGH */ 212 case EXC_DTMISS|EXC_USER: 213 KERNEL_PROC_LOCK(p); 214 215 if (frame->esr & (ESR_DST|ESR_DIZ)) 216 ftype = VM_PROT_WRITE; 217 218 DBPRINTF(TDB_ALL, ("trap(EXC_DSI|EXC_USER) at %x %s fault on %x %x\n", 219 frame->srr0, (ftype&VM_PROT_WRITE) ? "write" : "read", frame->dear, frame->esr)); 220 KASSERT(p == curproc && (p->p_stat == SONPROC)); 221 rv = uvm_fault(&p->p_vmspace->vm_map, 222 trunc_page(frame->dear), 0, ftype); 223 if (rv == 0) { 224 KERNEL_PROC_UNLOCK(p); 225 break; 226 } 227 if (rv == ENOMEM) { 228 printf("UVM: pid %d (%s), uid %d killed: " 229 "out of swap\n", 230 p->p_pid, p->p_comm, 231 p->p_cred && p->p_ucred ? 232 p->p_ucred->cr_uid : -1); 233 trapsignal(p, SIGKILL, EXC_DSI); 234 } else { 235 trapsignal(p, SIGSEGV, EXC_DSI); 236 } 237 KERNEL_PROC_UNLOCK(p); 238 break; 239 case EXC_ITMISS|EXC_USER: 240 case EXC_ISI|EXC_USER: 241 KERNEL_PROC_LOCK(p); 242 ftype = VM_PROT_READ | VM_PROT_EXECUTE; 243 DBPRINTF(TDB_ALL, ("trap(EXC_ISI|EXC_USER) at %x %s fault on %x tf %p\n", 244 frame->srr0, (ftype&VM_PROT_WRITE) ? "write" : "read", frame->srr0, frame)); 245 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 0, ftype); 246 if (rv == 0) { 247 KERNEL_PROC_UNLOCK(p); 248 break; 249 } 250 trapsignal(p, SIGSEGV, EXC_ISI); 251 KERNEL_PROC_UNLOCK(p); 252 break; 253 case EXC_SC|EXC_USER: 254 { 255 const struct sysent *callp; 256 size_t argsize; 257 register_t code, error; 258 register_t *params, rval[2]; 259 int n; 260 register_t args[10]; 261 262 KERNEL_PROC_LOCK(p); 263 264 uvmexp.syscalls++; 265 266 code = frame->fixreg[0]; 267 callp = p->p_emul->e_sysent; 268 params = frame->fixreg + FIRSTARG; 269 n = NARGREG; 270 271 switch (code) { 272 case SYS_syscall: 273 /* 274 * code is first argument, 275 * followed by actual args. 276 */ 277 code = *params++; 278 n -= 1; 279 break; 280 case SYS___syscall: 281 params++; 282 code = *params++; 283 n -= 2; 284 break; 285 default: 286 break; 287 } 288 289 code &= (SYS_NSYSENT - 1); 290 callp += code; 291 argsize = callp->sy_argsize; 292 293 if (argsize > n * sizeof(register_t)) { 294 memcpy(args, params, n * sizeof(register_t)); 295 error = copyin(MOREARGS(frame->fixreg[1]), 296 args + n, 297 argsize - n * sizeof(register_t)); 298 if (error) 299 goto syscall_bad; 300 params = args; 301 } 302 303 304 if ((error = trace_enter(p, code, args, rval)) != 0) 305 goto syscall_bad; 306 307 rval[0] = 0; 308 rval[1] = 0; 309 310 error = (*callp->sy_call)(p, params, rval); 311 switch (error) { 312 case 0: 313 frame->fixreg[FIRSTARG] = rval[0]; 314 frame->fixreg[FIRSTARG + 1] = rval[1]; 315 frame->cr &= ~0x10000000; 316 break; 317 case ERESTART: 318 /* 319 * Set user's pc back to redo the system call. 320 */ 321 frame->srr0 -= 4; 322 break; 323 case EJUSTRETURN: 324 /* nothing to do */ 325 break; 326 default: 327 syscall_bad: 328 if (p->p_emul->e_errno) 329 error = p->p_emul->e_errno[error]; 330 frame->fixreg[FIRSTARG] = error; 331 frame->cr |= 0x10000000; 332 break; 333 } 334 } 335 KERNEL_PROC_UNLOCK(p); 336 337 trace_exit(p, code, args, rval, error); 338 339 break; 340 341 case EXC_AST|EXC_USER: 342 astpending = 0; /* we are about to do it */ 343 KERNEL_PROC_LOCK(p); 344 uvmexp.softs++; 345 if (p->p_flag & P_OWEUPC) { 346 p->p_flag &= ~P_OWEUPC; 347 ADDUPROF(p); 348 } 349 /* Check whether we are being preempted. */ 350 if (want_resched) 351 preempt(NULL); 352 KERNEL_PROC_UNLOCK(p); 353 break; 354 355 356 case EXC_ALI|EXC_USER: 357 KERNEL_PROC_LOCK(p); 358 if (fix_unaligned(p, frame) != 0) 359 trapsignal(p, SIGBUS, EXC_ALI); 360 else 361 frame->srr0 += 4; 362 KERNEL_PROC_UNLOCK(p); 363 break; 364 365 case EXC_PGM|EXC_USER: 366 /* 367 * Illegal insn: 368 * 369 * let's try to see if it's FPU and can be emulated. 370 */ 371 uvmexp.traps ++; 372 if (!(p->p_addr->u_pcb.pcb_flags & PCB_FPU)) { 373 memset(&p->p_addr->u_pcb.pcb_fpu, 0, 374 sizeof p->p_addr->u_pcb.pcb_fpu); 375 p->p_addr->u_pcb.pcb_flags |= PCB_FPU; 376 } 377 378 if ((rv = fpu_emulate(frame, 379 (struct fpreg *)&p->p_addr->u_pcb.pcb_fpu))) { 380 KERNEL_PROC_LOCK(p); 381 trapsignal(p, rv, EXC_PGM); 382 KERNEL_PROC_UNLOCK(p); 383 } 384 break; 385 386 case EXC_MCHK: 387 { 388 faultbuf *fb; 389 390 if ((fb = p->p_addr->u_pcb.pcb_onfault) != NULL) { 391 frame->pid = KERNEL_PID; 392 frame->srr0 = (*fb)[0]; 393 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 394 frame->fixreg[1] = (*fb)[1]; 395 frame->fixreg[2] = (*fb)[2]; 396 frame->fixreg[3] = 1; /* Return TRUE */ 397 frame->cr = (*fb)[3]; 398 memcpy(&frame->fixreg[13], &(*fb)[4], 399 19 * sizeof(register_t)); 400 goto done; 401 } 402 } 403 goto brain_damage; 404 default: 405 brain_damage: 406 printf("trap type 0x%x at 0x%x\n", type, frame->srr0); 407 #ifdef DDB 408 if (kdb_trap(type, frame)) 409 goto done; 410 #endif 411 #ifdef TRAP_PANICWAIT 412 printf("Press a key to panic.\n"); 413 cngetc(); 414 #endif 415 panic("trap"); 416 } 417 418 /* Take pending signals. */ 419 { 420 int sig; 421 422 while ((sig = CURSIG(p)) != 0) 423 postsig(sig); 424 } 425 426 curcpu()->ci_schedstate.spc_curpriority = p->p_priority = p->p_usrpri; 427 done: 428 } 429 430 int 431 ctx_setup(int ctx, int srr1) 432 { 433 volatile struct pmap *pm; 434 435 /* Update PID if we're returning to user mode. */ 436 if (srr1 & PSL_PR) { 437 pm = curproc->p_vmspace->vm_map.pmap; 438 if (!pm->pm_ctx) { 439 ctx_alloc((struct pmap *)pm); 440 } 441 ctx = pm->pm_ctx; 442 if (srr1 & PSL_SE) { 443 int dbreg, mask = 0x48000000; 444 /* 445 * Set the Internal Debug and 446 * Instruction Completion bits of 447 * the DBCR0 register. 448 * 449 * XXX this is also used by jtag debuggers... 450 */ 451 __asm __volatile("mfspr %0,0x3f2;" 452 "or %0,%0,%1;" 453 "mtspr 0x3f2,%0;" : 454 "=&r" (dbreg) : "r" (mask)); 455 } 456 } 457 else if (!ctx) { 458 ctx = KERNEL_PID; 459 } 460 return (ctx); 461 } 462 463 void 464 child_return(void *arg) 465 { 466 struct proc *p = arg; 467 struct trapframe *tf = trapframe(p); 468 469 KERNEL_PROC_UNLOCK(p); 470 471 tf->fixreg[FIRSTARG] = 0; 472 tf->fixreg[FIRSTARG + 1] = 1; 473 tf->cr &= ~0x10000000; 474 tf->srr1 &= ~(PSL_FP|PSL_VEC); /* Disable FP & AltiVec, as we can't be them */ 475 #ifdef KTRACE 476 if (KTRPOINT(p, KTR_SYSRET)) { 477 KERNEL_PROC_LOCK(p); 478 ktrsysret(p, SYS_fork, 0, 0); 479 KERNEL_PROC_UNLOCK(p); 480 } 481 #endif 482 /* Profiling? XXX */ 483 curcpu()->ci_schedstate.spc_curpriority = p->p_priority; 484 } 485 486 /* 487 * Used by copyin()/copyout() 488 */ 489 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 490 extern void vunmaprange __P((vaddr_t, vsize_t)); 491 static int bigcopyin __P((const void *, void *, size_t )); 492 static int bigcopyout __P((const void *, void *, size_t )); 493 494 int 495 copyin(const void *udaddr, void *kaddr, size_t len) 496 { 497 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 498 int msr, pid, tmp, ctx; 499 faultbuf env; 500 501 /* For bigger buffers use the faster copy */ 502 if (len > 256) return (bigcopyin(udaddr, kaddr, len)); 503 504 if (setfault(env)) { 505 curpcb->pcb_onfault = 0; 506 return EFAULT; 507 } 508 509 if (!(ctx = pm->pm_ctx)) { 510 /* No context -- assign it one */ 511 ctx_alloc(pm); 512 ctx = pm->pm_ctx; 513 } 514 515 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 516 "mfmsr %0;" /* Save MSR */ 517 "li %1,0x20; " 518 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 519 "mfpid %1;" /* Save old PID */ 520 "sync; isync;" 521 522 "1: bdz 2f;" /* while len */ 523 "mtpid %3; sync;" /* Load user ctx */ 524 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 525 "sync; isync;" 526 "mtpid %1;sync;" 527 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 528 "sync; isync;" 529 "b 1b;" /* repeat */ 530 531 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 532 "sync; isync;" 533 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 534 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 535 536 curpcb->pcb_onfault = 0; 537 return 0; 538 } 539 540 static int 541 bigcopyin(const void *udaddr, void *kaddr, size_t len) 542 { 543 const char *up; 544 char *kp = kaddr; 545 struct proc *p = curproc; 546 int error; 547 548 if (!p) { 549 return EFAULT; 550 } 551 552 /* 553 * Stolen from physio(): 554 */ 555 PHOLD(p); 556 error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ); 557 if (error) { 558 PRELE(p); 559 return EFAULT; 560 } 561 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 562 563 memcpy(kp, up, len); 564 vunmaprange((vaddr_t)up, len); 565 uvm_vsunlock(p, (caddr_t)udaddr, len); 566 PRELE(p); 567 568 return 0; 569 } 570 571 int 572 copyout(const void *kaddr, void *udaddr, size_t len) 573 { 574 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 575 int msr, pid, tmp, ctx; 576 faultbuf env; 577 578 /* For big copies use more efficient routine */ 579 if (len > 256) return (bigcopyout(kaddr, udaddr, len)); 580 581 if (setfault(env)) { 582 curpcb->pcb_onfault = 0; 583 return EFAULT; 584 } 585 586 if (!(ctx = pm->pm_ctx)) { 587 /* No context -- assign it one */ 588 ctx_alloc(pm); 589 ctx = pm->pm_ctx; 590 } 591 592 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 593 "mfmsr %0;" /* Save MSR */ 594 "li %1,0x20; " 595 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 596 "mfpid %1;" /* Save old PID */ 597 "sync; isync;" 598 599 "1: bdz 2f;" /* while len */ 600 "mtpid %1;sync;" 601 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 602 "sync; isync;" 603 "mtpid %3; sync;" /* Load user ctx */ 604 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 605 "sync; isync;" 606 "b 1b;" /* repeat */ 607 608 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 609 "sync; isync;" 610 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 611 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 612 613 curpcb->pcb_onfault = 0; 614 return 0; 615 } 616 617 static int 618 bigcopyout(const void *kaddr, void *udaddr, size_t len) 619 { 620 char *up; 621 const char *kp = (char *)kaddr; 622 struct proc *p = curproc; 623 int error; 624 625 if (!p) { 626 return EFAULT; 627 } 628 629 /* 630 * Stolen from physio(): 631 */ 632 PHOLD(p); 633 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); 634 if (error) { 635 PRELE(p); 636 return EFAULT; 637 } 638 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 639 VM_PROT_READ|VM_PROT_WRITE); 640 641 memcpy(up, kp, len); 642 vunmaprange((vaddr_t)up, len); 643 uvm_vsunlock(p, udaddr, len); 644 PRELE(p); 645 646 return 0; 647 } 648 649 /* 650 * kcopy(const void *src, void *dst, size_t len); 651 * 652 * Copy len bytes from src to dst, aborting if we encounter a fatal 653 * page fault. 654 * 655 * kcopy() _must_ save and restore the old fault handler since it is 656 * called by uiomove(), which may be in the path of servicing a non-fatal 657 * page fault. 658 */ 659 int 660 kcopy(const void *src, void *dst, size_t len) 661 { 662 faultbuf env, *oldfault; 663 664 oldfault = curpcb->pcb_onfault; 665 if (setfault(env)) { 666 curpcb->pcb_onfault = oldfault; 667 return EFAULT; 668 } 669 670 memcpy(dst, src, len); 671 672 curpcb->pcb_onfault = oldfault; 673 return 0; 674 } 675 676 int 677 badaddr(void *addr, size_t size) 678 { 679 680 return badaddr_read(addr, size, NULL); 681 } 682 683 int 684 badaddr_read(void *addr, size_t size, int *rptr) 685 { 686 faultbuf env; 687 int x; 688 689 /* Get rid of any stale machine checks that have been waiting. */ 690 __asm __volatile ("sync; isync"); 691 692 if (setfault(env)) { 693 curpcb->pcb_onfault = 0; 694 __asm __volatile ("sync"); 695 return 1; 696 } 697 698 __asm __volatile ("sync"); 699 700 switch (size) { 701 case 1: 702 x = *(volatile int8_t *)addr; 703 break; 704 case 2: 705 x = *(volatile int16_t *)addr; 706 break; 707 case 4: 708 x = *(volatile int32_t *)addr; 709 break; 710 default: 711 panic("badaddr: invalid size (%d)", size); 712 } 713 714 /* Make sure we took the machine check, if we caused one. */ 715 __asm __volatile ("sync; isync"); 716 717 curpcb->pcb_onfault = 0; 718 __asm __volatile ("sync"); /* To be sure. */ 719 720 /* Use the value to avoid reorder. */ 721 if (rptr) 722 *rptr = x; 723 724 return 0; 725 } 726 727 /* 728 * For now, this only deals with the particular unaligned access case 729 * that gcc tends to generate. Eventually it should handle all of the 730 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 731 */ 732 733 static int 734 fix_unaligned(struct proc *p, struct trapframe *frame) 735 { 736 737 return -1; 738 } 739
Indexes created Tue Sep 30 20:09:53 GMT 2025