trap.c revision 1.47.2.1
1 /* $NetBSD: trap.c,v 1.47.2.1 2007/12/27 02:18:17 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 1.47.2.1 2007/12/27 02:18:17 ad Exp $"); 71 72 #include "opt_altivec.h" 73 #include "opt_ddb.h" 74 #include "opt_kgdb.h" 75 76 #include <sys/param.h> 77 #include <sys/proc.h> 78 #include <sys/reboot.h> 79 #include <sys/syscall.h> 80 #include <sys/systm.h> 81 #include <sys/user.h> 82 #include <sys/pool.h> 83 #include <sys/userret.h> 84 #include <sys/kauth.h> 85 86 #if defined(KGDB) 87 #include <sys/kgdb.h> 88 #endif 89 90 #include <uvm/uvm_extern.h> 91 92 #include <dev/cons.h> 93 94 #include <machine/cpu.h> 95 #include <machine/db_machdep.h> 96 #include <machine/fpu.h> 97 #include <machine/frame.h> 98 #include <machine/pcb.h> 99 #include <machine/psl.h> 100 #include <machine/trap.h> 101 102 #include <powerpc/spr.h> 103 #include <powerpc/ibm4xx/pmap.h> 104 #include <powerpc/ibm4xx/tlb.h> 105 #include <powerpc/fpu/fpu_extern.h> 106 107 /* These definitions should probably be somewhere else XXX */ 108 #define FIRSTARG 3 /* first argument is in reg 3 */ 109 #define NARGREG 8 /* 8 args are in registers */ 110 #define MOREARGS(sp) ((void *)((int)(sp) + 8)) /* more args go here */ 111 112 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 113 114 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 115 /* Why are these not defined in a header? */ 116 int badaddr __P((void *, size_t)); 117 int badaddr_read __P((void *, size_t, int *)); 118 int ctx_setup __P((int, int)); 119 120 #ifdef DEBUG 121 #define TDB_ALL 0x1 122 int trapdebug = /* TDB_ALL */ 0; 123 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y 124 #else 125 #define DBPRINTF(x, y) 126 #endif 127 128 void 129 trap(struct trapframe *frame) 130 { 131 struct lwp *l = curlwp; 132 struct proc *p = l ? l->l_proc : NULL; 133 int type = frame->exc; 134 int ftype, rv; 135 ksiginfo_t ksi; 136 137 KASSERT(l == 0 || (l->l_stat == LSONPROC)); 138 139 if (frame->srr1 & PSL_PR) { 140 LWP_CACHE_CREDS(l, p); 141 type |= EXC_USER; 142 } 143 144 ftype = VM_PROT_READ; 145 146 DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n", 147 type, frame->srr0, frame, &frame)); 148 149 switch (type) { 150 case EXC_DEBUG|EXC_USER: 151 { 152 int srr2, srr3; 153 154 __asm volatile("mfspr %0,0x3f0" : 155 "=r" (rv), "=r" (srr2), "=r" (srr3) :); 156 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, 157 srr3); 158 /* XXX fall through or break here?! */ 159 } 160 /* 161 * DEBUG intr -- probably single-step. 162 */ 163 case EXC_TRC|EXC_USER: 164 frame->srr1 &= ~PSL_SE; 165 KSI_INIT_TRAP(&ksi); 166 ksi.ksi_signo = SIGTRAP; 167 ksi.ksi_trap = EXC_TRC; 168 ksi.ksi_addr = (void *)frame->srr0; 169 trapsignal(l, &ksi); 170 break; 171 172 /* 173 * If we could not find and install appropriate TLB entry, fall through. 174 */ 175 176 case EXC_DSI: 177 /* FALLTHROUGH */ 178 case EXC_DTMISS: 179 { 180 struct vm_map *map; 181 vaddr_t va; 182 struct faultbuf *fb = NULL; 183 184 va = frame->dar; 185 if (frame->tf_xtra[TF_PID] == KERNEL_PID) { 186 map = kernel_map; 187 } else { 188 map = &p->p_vmspace->vm_map; 189 } 190 191 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 192 ftype = VM_PROT_WRITE; 193 194 DBPRINTF(TDB_ALL, 195 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 196 frame->srr0, 197 (ftype & VM_PROT_WRITE) ? "write" : "read", 198 (void *)va, frame->tf_xtra[TF_ESR])); 199 rv = uvm_fault(map, trunc_page(va), ftype); 200 if (rv == 0) 201 goto done; 202 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 203 frame->tf_xtra[TF_PID] = KERNEL_PID; 204 frame->srr0 = fb->fb_pc; 205 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 206 frame->fixreg[1] = fb->fb_sp; 207 frame->fixreg[2] = fb->fb_r2; 208 frame->fixreg[3] = 1; /* Return TRUE */ 209 frame->cr = fb->fb_cr; 210 memcpy(&frame->fixreg[13], fb->fb_fixreg, 211 sizeof(fb->fb_fixreg)); 212 goto done; 213 } 214 } 215 goto brain_damage; 216 217 case EXC_DSI|EXC_USER: 218 /* FALLTHROUGH */ 219 case EXC_DTMISS|EXC_USER: 220 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 221 ftype = VM_PROT_WRITE; 222 223 DBPRINTF(TDB_ALL, 224 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 225 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 226 frame->dar, frame->tf_xtra[TF_ESR])); 227 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 228 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 229 ftype); 230 if (rv == 0) { 231 break; 232 } 233 KSI_INIT_TRAP(&ksi); 234 ksi.ksi_signo = SIGSEGV; 235 ksi.ksi_trap = EXC_DSI; 236 ksi.ksi_addr = (void *)frame->dar; 237 if (rv == ENOMEM) { 238 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 239 "out of swap\n", 240 p->p_pid, p->p_comm, l->l_lid, 241 l->l_cred ? 242 kauth_cred_geteuid(l->l_cred) : -1); 243 ksi.ksi_signo = SIGKILL; 244 } 245 trapsignal(l, &ksi); 246 break; 247 248 case EXC_ITMISS|EXC_USER: 249 case EXC_ISI|EXC_USER: 250 ftype = VM_PROT_EXECUTE; 251 DBPRINTF(TDB_ALL, 252 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 253 frame->srr0, frame)); 254 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 255 ftype); 256 if (rv == 0) { 257 break; 258 } 259 KSI_INIT_TRAP(&ksi); 260 ksi.ksi_signo = SIGSEGV; 261 ksi.ksi_trap = EXC_ISI; 262 ksi.ksi_addr = (void *)frame->srr0; 263 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR); 264 trapsignal(l, &ksi); 265 break; 266 267 case EXC_AST|EXC_USER: 268 curcpu()->ci_astpending = 0; /* we are about to do it */ 269 uvmexp.softs++; 270 if (l->l_pflag & LP_OWEUPC) { 271 l->l_pflag &= ~LP_OWEUPC; 272 ADDUPROF(l); 273 } 274 /* Check whether we are being preempted. */ 275 if (curcpu()->ci_want_resched) 276 preempt(); 277 break; 278 279 280 case EXC_ALI|EXC_USER: 281 if (fix_unaligned(l, frame) != 0) { 282 KSI_INIT_TRAP(&ksi); 283 ksi.ksi_signo = SIGBUS; 284 ksi.ksi_trap = EXC_ALI; 285 ksi.ksi_addr = (void *)frame->dar; 286 trapsignal(l, &ksi); 287 } else 288 frame->srr0 += 4; 289 break; 290 291 case EXC_PGM|EXC_USER: 292 /* 293 * Illegal insn: 294 * 295 * let's try to see if it's FPU and can be emulated. 296 */ 297 uvmexp.traps++; 298 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 299 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 300 sizeof l->l_addr->u_pcb.pcb_fpu); 301 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 302 } 303 304 if ((rv = fpu_emulate(frame, 305 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 306 KSI_INIT_TRAP(&ksi); 307 ksi.ksi_signo = rv; 308 ksi.ksi_trap = EXC_PGM; 309 ksi.ksi_addr = (void *)frame->srr0; 310 trapsignal(l, &ksi); 311 } 312 break; 313 314 case EXC_MCHK: 315 { 316 struct faultbuf *fb; 317 318 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 319 frame->tf_xtra[TF_PID] = KERNEL_PID; 320 frame->srr0 = fb->fb_pc; 321 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 322 frame->fixreg[1] = fb->fb_sp; 323 frame->fixreg[2] = fb->fb_r2; 324 frame->fixreg[3] = 1; /* Return TRUE */ 325 frame->cr = fb->fb_cr; 326 memcpy(&frame->fixreg[13], fb->fb_fixreg, 327 sizeof(fb->fb_fixreg)); 328 goto done; 329 } 330 } 331 goto brain_damage; 332 default: 333 brain_damage: 334 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 335 #if defined(DDB) || defined(KGDB) 336 if (kdb_trap(type, frame)) 337 goto done; 338 #endif 339 #ifdef TRAP_PANICWAIT 340 printf("Press a key to panic.\n"); 341 cngetc(); 342 #endif 343 panic("trap"); 344 } 345 346 /* Invoke MI userret code */ 347 mi_userret(l); 348 done: 349 return; 350 } 351 352 int 353 ctx_setup(int ctx, int srr1) 354 { 355 volatile struct pmap *pm; 356 357 /* Update PID if we're returning to user mode. */ 358 if (srr1 & PSL_PR) { 359 pm = curproc->p_vmspace->vm_map.pmap; 360 if (!pm->pm_ctx) { 361 ctx_alloc(__UNVOLATILE(pm)); 362 } 363 ctx = pm->pm_ctx; 364 if (srr1 & PSL_SE) { 365 int dbreg, mask = 0x48000000; 366 /* 367 * Set the Internal Debug and 368 * Instruction Completion bits of 369 * the DBCR0 register. 370 * 371 * XXX this is also used by jtag debuggers... 372 */ 373 __asm volatile("mfspr %0,0x3f2;" 374 "or %0,%0,%1;" 375 "mtspr 0x3f2,%0;" : 376 "=&r" (dbreg) : "r" (mask)); 377 } 378 } 379 else if (!ctx) { 380 ctx = KERNEL_PID; 381 } 382 return (ctx); 383 } 384 385 /* 386 * Used by copyin()/copyout() 387 */ 388 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 389 extern void vunmaprange __P((vaddr_t, vsize_t)); 390 static int bigcopyin __P((const void *, void *, size_t )); 391 static int bigcopyout __P((const void *, void *, size_t )); 392 393 int 394 copyin(const void *udaddr, void *kaddr, size_t len) 395 { 396 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 397 int msr, pid, tmp, ctx, count=0; 398 struct faultbuf env; 399 400 /* For bigger buffers use the faster copy */ 401 if (len > 1024) 402 return (bigcopyin(udaddr, kaddr, len)); 403 404 if (setfault(&env)) { 405 curpcb->pcb_onfault = 0; 406 return EFAULT; 407 } 408 409 if (!(ctx = pm->pm_ctx)) { 410 /* No context -- assign it one */ 411 ctx_alloc(pm); 412 ctx = pm->pm_ctx; 413 } 414 415 __asm volatile( 416 " mfmsr %[msr];" /* Save MSR */ 417 " li %[pid],0x20; " 418 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ 419 " mfpid %[pid];" /* Save old PID */ 420 " sync; isync;" 421 422 " srwi. %[count],%[len],0x2;" /* How many words? */ 423 " beq- 2f;" /* No words. Go do bytes */ 424 " mtctr %[count];" 425 "1: mtpid %[ctx]; sync;" 426 " lswi %[tmp],%[udaddr],4;" /* Load user word */ 427 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 428 " sync; isync;" 429 " mtpid %[pid];sync;" 430 " stswi %[tmp],%[kaddr],4;" /* Store kernel word */ 431 " dcbf 0,%[kaddr];" /* flush cache */ 432 " addi %[kaddr],%[kaddr],0x4;" /* next udaddr word */ 433 " sync; isync;" 434 " bdnz 1b;" /* repeat */ 435 436 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 437 " addi %[count],%[count],0x1;" 438 " mtctr %[count];" 439 "3: bdz 10f;" /* while count */ 440 " mtpid %[ctx];sync;" 441 " lbz %[tmp],0(%[udaddr]);" /* Load user byte */ 442 " addi %[udaddr],%[udaddr],0x1;" /* next udaddr byte */ 443 " sync; isync;" 444 " mtpid %[pid]; sync;" 445 " stb %[tmp],0(%[kaddr]);" /* Store kernel byte */ 446 " dcbf 0,%[kaddr];" /* flush cache */ 447 " addi %[kaddr],%[kaddr],0x1;" 448 " sync; isync;" 449 " b 3b;" 450 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 451 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 452 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 453 454 curpcb->pcb_onfault = 0; 455 return 0; 456 } 457 458 static int 459 bigcopyin(const void *udaddr, void *kaddr, size_t len) 460 { 461 const char *up; 462 char *kp = kaddr; 463 struct lwp *l = curlwp; 464 struct proc *p; 465 int error; 466 467 if (!l) { 468 return EFAULT; 469 } 470 471 p = l->l_proc; 472 473 /* 474 * Stolen from physio(): 475 */ 476 uvm_lwp_hold(l); 477 error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ); 478 if (error) { 479 uvm_lwp_rele(l); 480 return EFAULT; 481 } 482 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 483 484 memcpy(kp, up, len); 485 vunmaprange((vaddr_t)up, len); 486 uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len); 487 uvm_lwp_rele(l); 488 489 return 0; 490 } 491 492 int 493 copyout(const void *kaddr, void *udaddr, size_t len) 494 { 495 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 496 int msr, pid, tmp, ctx, count=0; 497 struct faultbuf env; 498 499 /* For big copies use more efficient routine */ 500 if (len > 1024) 501 return (bigcopyout(kaddr, udaddr, 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( 515 " mfmsr %[msr];" /* Save MSR */ \ 516 " li %[pid],0x20; " \ 517 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ \ 518 " mfpid %[pid];" /* Save old PID */ \ 519 " sync; isync;" 520 521 " srwi. %[count],%[len],0x2;" /* How many words? */ 522 " beq- 2f;" /* No words. Go do bytes */ 523 " mtctr %[count];" 524 "1: mtpid %[pid];sync;" 525 " lswi %[tmp],%[kaddr],4;" /* Load kernel word */ 526 " addi %[kaddr],%[kaddr],0x4;" /* next kaddr word */ 527 " sync; isync;" 528 " mtpid %[ctx]; sync;" 529 " stswi %[tmp],%[udaddr],4;" /* Store user word */ 530 " dcbf 0,%[udaddr];" /* flush cache */ 531 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 532 " sync; isync;" 533 " bdnz 1b;" /* repeat */ 534 535 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 536 " addi %[count],%[count],0x1;" 537 " mtctr %[count];" 538 "3: bdz 10f;" /* while count */ 539 " mtpid %[pid];sync;" 540 " lbz %[tmp],0(%[kaddr]);" /* Load kernel byte */ 541 " addi %[kaddr],%[kaddr],0x1;" /* next kaddr byte */ 542 " sync; isync;" 543 " mtpid %[ctx]; sync;" 544 " stb %[tmp],0(%[udaddr]);" /* Store user byte */ 545 " dcbf 0,%[udaddr];" /* flush cache */ 546 " addi %[udaddr],%[udaddr],0x1;" 547 " sync; isync;" 548 " b 3b;" 549 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 550 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 551 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 552 553 curpcb->pcb_onfault = 0; 554 return 0; 555 } 556 557 static int 558 bigcopyout(const void *kaddr, void *udaddr, size_t len) 559 { 560 char *up; 561 const char *kp = (const char *)kaddr; 562 struct lwp *l = curlwp; 563 struct proc *p; 564 int error; 565 566 if (!l) { 567 return EFAULT; 568 } 569 570 p = l->l_proc; 571 572 /* 573 * Stolen from physio(): 574 */ 575 uvm_lwp_hold(l); 576 error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE); 577 if (error) { 578 uvm_lwp_rele(l); 579 return EFAULT; 580 } 581 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 582 VM_PROT_READ | VM_PROT_WRITE); 583 584 memcpy(up, kp, len); 585 vunmaprange((vaddr_t)up, len); 586 uvm_vsunlock(p->p_vmspace, udaddr, len); 587 uvm_lwp_rele(l); 588 589 return 0; 590 } 591 592 /* 593 * kcopy(const void *src, void *dst, size_t len); 594 * 595 * Copy len bytes from src to dst, aborting if we encounter a fatal 596 * page fault. 597 * 598 * kcopy() _must_ save and restore the old fault handler since it is 599 * called by uiomove(), which may be in the path of servicing a non-fatal 600 * page fault. 601 */ 602 int 603 kcopy(const void *src, void *dst, size_t len) 604 { 605 struct faultbuf env, *oldfault; 606 607 oldfault = curpcb->pcb_onfault; 608 if (setfault(&env)) { 609 curpcb->pcb_onfault = oldfault; 610 return EFAULT; 611 } 612 613 memcpy(dst, src, len); 614 615 curpcb->pcb_onfault = oldfault; 616 return 0; 617 } 618 619 int 620 badaddr(void *addr, size_t size) 621 { 622 623 return badaddr_read(addr, size, NULL); 624 } 625 626 int 627 badaddr_read(void *addr, size_t size, int *rptr) 628 { 629 struct faultbuf env; 630 int x; 631 632 /* Get rid of any stale machine checks that have been waiting. */ 633 __asm volatile ("sync; isync"); 634 635 if (setfault(&env)) { 636 curpcb->pcb_onfault = 0; 637 __asm volatile ("sync"); 638 return 1; 639 } 640 641 __asm volatile ("sync"); 642 643 switch (size) { 644 case 1: 645 x = *(volatile int8_t *)addr; 646 break; 647 case 2: 648 x = *(volatile int16_t *)addr; 649 break; 650 case 4: 651 x = *(volatile int32_t *)addr; 652 break; 653 default: 654 panic("badaddr: invalid size (%d)", size); 655 } 656 657 /* Make sure we took the machine check, if we caused one. */ 658 __asm volatile ("sync; isync"); 659 660 curpcb->pcb_onfault = 0; 661 __asm volatile ("sync"); /* To be sure. */ 662 663 /* Use the value to avoid reorder. */ 664 if (rptr) 665 *rptr = x; 666 667 return 0; 668 } 669 670 /* 671 * For now, this only deals with the particular unaligned access case 672 * that gcc tends to generate. Eventually it should handle all of the 673 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 674 */ 675 676 static int 677 fix_unaligned(struct lwp *l, struct trapframe *frame) 678 { 679 680 return -1; 681 } 682 683 /* 684 * Start a new LWP 685 */ 686 void 687 startlwp(arg) 688 void *arg; 689 { 690 int err; 691 ucontext_t *uc = arg; 692 struct lwp *l = curlwp; 693 694 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 695 #if DIAGNOSTIC 696 if (err) { 697 printf("Error %d from cpu_setmcontext.", err); 698 } 699 #endif 700 pool_put(&lwp_uc_pool, uc); 701 702 /* Invoke MI userret code */ 703 mi_userret(l); 704 } 705
Indexes created Tue Sep 30 20:09:53 GMT 2025