trap.c revision 1.5
1 /* $NetBSD: trap.c,v 1.5 2002/06/17 21:08:56 christos 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, params, 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 KERNEL_PROC_UNLOCK(p); 335 336 trace_exit(p, code, args, rval, error); 337 } 338 break; 339 340 case EXC_AST|EXC_USER: 341 astpending = 0; /* we are about to do it */ 342 KERNEL_PROC_LOCK(p); 343 uvmexp.softs++; 344 if (p->p_flag & P_OWEUPC) { 345 p->p_flag &= ~P_OWEUPC; 346 ADDUPROF(p); 347 } 348 /* Check whether we are being preempted. */ 349 if (want_resched) 350 preempt(NULL); 351 KERNEL_PROC_UNLOCK(p); 352 break; 353 354 355 case EXC_ALI|EXC_USER: 356 KERNEL_PROC_LOCK(p); 357 if (fix_unaligned(p, frame) != 0) 358 trapsignal(p, SIGBUS, EXC_ALI); 359 else 360 frame->srr0 += 4; 361 KERNEL_PROC_UNLOCK(p); 362 break; 363 364 case EXC_PGM|EXC_USER: 365 /* 366 * Illegal insn: 367 * 368 * let's try to see if it's FPU and can be emulated. 369 */ 370 uvmexp.traps ++; 371 if (!(p->p_addr->u_pcb.pcb_flags & PCB_FPU)) { 372 memset(&p->p_addr->u_pcb.pcb_fpu, 0, 373 sizeof p->p_addr->u_pcb.pcb_fpu); 374 p->p_addr->u_pcb.pcb_flags |= PCB_FPU; 375 } 376 377 if ((rv = fpu_emulate(frame, 378 (struct fpreg *)&p->p_addr->u_pcb.pcb_fpu))) { 379 KERNEL_PROC_LOCK(p); 380 trapsignal(p, rv, EXC_PGM); 381 KERNEL_PROC_UNLOCK(p); 382 } 383 break; 384 385 case EXC_MCHK: 386 { 387 faultbuf *fb; 388 389 if ((fb = p->p_addr->u_pcb.pcb_onfault) != NULL) { 390 frame->pid = KERNEL_PID; 391 frame->srr0 = (*fb)[0]; 392 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 393 frame->fixreg[1] = (*fb)[1]; 394 frame->fixreg[2] = (*fb)[2]; 395 frame->fixreg[3] = 1; /* Return TRUE */ 396 frame->cr = (*fb)[3]; 397 memcpy(&frame->fixreg[13], &(*fb)[4], 398 19 * sizeof(register_t)); 399 goto done; 400 } 401 } 402 goto brain_damage; 403 default: 404 brain_damage: 405 printf("trap type 0x%x at 0x%x\n", type, frame->srr0); 406 #ifdef DDB 407 if (kdb_trap(type, frame)) 408 goto done; 409 #endif 410 #ifdef TRAP_PANICWAIT 411 printf("Press a key to panic.\n"); 412 cngetc(); 413 #endif 414 panic("trap"); 415 } 416 417 /* Take pending signals. */ 418 { 419 int sig; 420 421 while ((sig = CURSIG(p)) != 0) 422 postsig(sig); 423 } 424 425 curcpu()->ci_schedstate.spc_curpriority = p->p_priority = p->p_usrpri; 426 done: 427 } 428 429 int 430 ctx_setup(int ctx, int srr1) 431 { 432 volatile struct pmap *pm; 433 434 /* Update PID if we're returning to user mode. */ 435 if (srr1 & PSL_PR) { 436 pm = curproc->p_vmspace->vm_map.pmap; 437 if (!pm->pm_ctx) { 438 ctx_alloc((struct pmap *)pm); 439 } 440 ctx = pm->pm_ctx; 441 if (srr1 & PSL_SE) { 442 int dbreg, mask = 0x48000000; 443 /* 444 * Set the Internal Debug and 445 * Instruction Completion bits of 446 * the DBCR0 register. 447 * 448 * XXX this is also used by jtag debuggers... 449 */ 450 __asm __volatile("mfspr %0,0x3f2;" 451 "or %0,%0,%1;" 452 "mtspr 0x3f2,%0;" : 453 "=&r" (dbreg) : "r" (mask)); 454 } 455 } 456 else if (!ctx) { 457 ctx = KERNEL_PID; 458 } 459 return (ctx); 460 } 461 462 void 463 child_return(void *arg) 464 { 465 struct proc *p = arg; 466 struct trapframe *tf = trapframe(p); 467 468 KERNEL_PROC_UNLOCK(p); 469 470 tf->fixreg[FIRSTARG] = 0; 471 tf->fixreg[FIRSTARG + 1] = 1; 472 tf->cr &= ~0x10000000; 473 tf->srr1 &= ~(PSL_FP|PSL_VEC); /* Disable FP & AltiVec, as we can't be them */ 474 #ifdef KTRACE 475 if (KTRPOINT(p, KTR_SYSRET)) { 476 KERNEL_PROC_LOCK(p); 477 ktrsysret(p, SYS_fork, 0, 0); 478 KERNEL_PROC_UNLOCK(p); 479 } 480 #endif 481 /* Profiling? XXX */ 482 curcpu()->ci_schedstate.spc_curpriority = p->p_priority; 483 } 484 485 /* 486 * Used by copyin()/copyout() 487 */ 488 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 489 extern void vunmaprange __P((vaddr_t, vsize_t)); 490 static int bigcopyin __P((const void *, void *, size_t )); 491 static int bigcopyout __P((const void *, void *, size_t )); 492 493 int 494 copyin(const void *udaddr, void *kaddr, size_t len) 495 { 496 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 497 int msr, pid, tmp, ctx; 498 faultbuf env; 499 500 /* For bigger buffers use the faster copy */ 501 if (len > 256) return (bigcopyin(udaddr, kaddr, len)); 502 503 if (setfault(env)) { 504 curpcb->pcb_onfault = 0; 505 return EFAULT; 506 } 507 508 if (!(ctx = pm->pm_ctx)) { 509 /* No context -- assign it one */ 510 ctx_alloc(pm); 511 ctx = pm->pm_ctx; 512 } 513 514 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 515 "mfmsr %0;" /* Save MSR */ 516 "li %1,0x20; " 517 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 518 "mfpid %1;" /* Save old PID */ 519 "sync; isync;" 520 521 "1: bdz 2f;" /* while len */ 522 "mtpid %3; sync;" /* Load user ctx */ 523 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 524 "sync; isync;" 525 "mtpid %1;sync;" 526 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 527 "sync; isync;" 528 "b 1b;" /* repeat */ 529 530 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 531 "sync; isync;" 532 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 533 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 534 535 curpcb->pcb_onfault = 0; 536 return 0; 537 } 538 539 static int 540 bigcopyin(const void *udaddr, void *kaddr, size_t len) 541 { 542 const char *up; 543 char *kp = kaddr; 544 struct proc *p = curproc; 545 int error; 546 547 if (!p) { 548 return EFAULT; 549 } 550 551 /* 552 * Stolen from physio(): 553 */ 554 PHOLD(p); 555 error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ); 556 if (error) { 557 PRELE(p); 558 return EFAULT; 559 } 560 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 561 562 memcpy(kp, up, len); 563 vunmaprange((vaddr_t)up, len); 564 uvm_vsunlock(p, (caddr_t)udaddr, len); 565 PRELE(p); 566 567 return 0; 568 } 569 570 int 571 copyout(const void *kaddr, void *udaddr, size_t len) 572 { 573 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 574 int msr, pid, tmp, ctx; 575 faultbuf env; 576 577 /* For big copies use more efficient routine */ 578 if (len > 256) return (bigcopyout(kaddr, udaddr, len)); 579 580 if (setfault(env)) { 581 curpcb->pcb_onfault = 0; 582 return EFAULT; 583 } 584 585 if (!(ctx = pm->pm_ctx)) { 586 /* No context -- assign it one */ 587 ctx_alloc(pm); 588 ctx = pm->pm_ctx; 589 } 590 591 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 592 "mfmsr %0;" /* Save MSR */ 593 "li %1,0x20; " 594 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 595 "mfpid %1;" /* Save old PID */ 596 "sync; isync;" 597 598 "1: bdz 2f;" /* while len */ 599 "mtpid %1;sync;" 600 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 601 "sync; isync;" 602 "mtpid %3; sync;" /* Load user ctx */ 603 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 604 "sync; isync;" 605 "b 1b;" /* repeat */ 606 607 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 608 "sync; isync;" 609 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 610 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 611 612 curpcb->pcb_onfault = 0; 613 return 0; 614 } 615 616 static int 617 bigcopyout(const void *kaddr, void *udaddr, size_t len) 618 { 619 char *up; 620 const char *kp = (char *)kaddr; 621 struct proc *p = curproc; 622 int error; 623 624 if (!p) { 625 return EFAULT; 626 } 627 628 /* 629 * Stolen from physio(): 630 */ 631 PHOLD(p); 632 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); 633 if (error) { 634 PRELE(p); 635 return EFAULT; 636 } 637 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 638 VM_PROT_READ|VM_PROT_WRITE); 639 640 memcpy(up, kp, len); 641 vunmaprange((vaddr_t)up, len); 642 uvm_vsunlock(p, udaddr, len); 643 PRELE(p); 644 645 return 0; 646 } 647 648 /* 649 * kcopy(const void *src, void *dst, size_t len); 650 * 651 * Copy len bytes from src to dst, aborting if we encounter a fatal 652 * page fault. 653 * 654 * kcopy() _must_ save and restore the old fault handler since it is 655 * called by uiomove(), which may be in the path of servicing a non-fatal 656 * page fault. 657 */ 658 int 659 kcopy(const void *src, void *dst, size_t len) 660 { 661 faultbuf env, *oldfault; 662 663 oldfault = curpcb->pcb_onfault; 664 if (setfault(env)) { 665 curpcb->pcb_onfault = oldfault; 666 return EFAULT; 667 } 668 669 memcpy(dst, src, len); 670 671 curpcb->pcb_onfault = oldfault; 672 return 0; 673 } 674 675 int 676 badaddr(void *addr, size_t size) 677 { 678 679 return badaddr_read(addr, size, NULL); 680 } 681 682 int 683 badaddr_read(void *addr, size_t size, int *rptr) 684 { 685 faultbuf env; 686 int x; 687 688 /* Get rid of any stale machine checks that have been waiting. */ 689 __asm __volatile ("sync; isync"); 690 691 if (setfault(env)) { 692 curpcb->pcb_onfault = 0; 693 __asm __volatile ("sync"); 694 return 1; 695 } 696 697 __asm __volatile ("sync"); 698 699 switch (size) { 700 case 1: 701 x = *(volatile int8_t *)addr; 702 break; 703 case 2: 704 x = *(volatile int16_t *)addr; 705 break; 706 case 4: 707 x = *(volatile int32_t *)addr; 708 break; 709 default: 710 panic("badaddr: invalid size (%d)", size); 711 } 712 713 /* Make sure we took the machine check, if we caused one. */ 714 __asm __volatile ("sync; isync"); 715 716 curpcb->pcb_onfault = 0; 717 __asm __volatile ("sync"); /* To be sure. */ 718 719 /* Use the value to avoid reorder. */ 720 if (rptr) 721 *rptr = x; 722 723 return 0; 724 } 725 726 /* 727 * For now, this only deals with the particular unaligned access case 728 * that gcc tends to generate. Eventually it should handle all of the 729 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 730 */ 731 732 static int 733 fix_unaligned(struct proc *p, struct trapframe *frame) 734 { 735 736 return -1; 737 } 738
Indexes created Tue Sep 30 20:09:53 GMT 2025