trap.c revision 1.48.12.1
1 /* $NetBSD: trap.c,v 1.48.12.1 2008/05/10 23:48:45 wrstuden 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 1.48.12.1 2008/05/10 23:48:45 wrstuden 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/sa.h> 84 #include <sys/savar.h> 85 #include <sys/userret.h> 86 #include <sys/kauth.h> 87 88 #if defined(KGDB) 89 #include <sys/kgdb.h> 90 #endif 91 92 #include <uvm/uvm_extern.h> 93 94 #include <dev/cons.h> 95 96 #include <machine/cpu.h> 97 #include <machine/db_machdep.h> 98 #include <machine/fpu.h> 99 #include <machine/frame.h> 100 #include <machine/pcb.h> 101 #include <machine/psl.h> 102 #include <machine/trap.h> 103 104 #include <powerpc/spr.h> 105 #include <powerpc/ibm4xx/pmap.h> 106 #include <powerpc/ibm4xx/tlb.h> 107 #include <powerpc/fpu/fpu_extern.h> 108 109 /* These definitions should probably be somewhere else XXX */ 110 #define FIRSTARG 3 /* first argument is in reg 3 */ 111 #define NARGREG 8 /* 8 args are in registers */ 112 #define MOREARGS(sp) ((void *)((int)(sp) + 8)) /* more args go here */ 113 114 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 115 116 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 117 /* Why are these not defined in a header? */ 118 int badaddr __P((void *, size_t)); 119 int badaddr_read __P((void *, size_t, int *)); 120 int ctx_setup __P((int, int)); 121 122 #ifdef DEBUG 123 #define TDB_ALL 0x1 124 int trapdebug = /* TDB_ALL */ 0; 125 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y 126 #else 127 #define DBPRINTF(x, y) 128 #endif 129 130 void 131 trap(struct trapframe *frame) 132 { 133 struct lwp *l = curlwp; 134 struct proc *p = l ? l->l_proc : NULL; 135 int type = frame->exc; 136 int ftype, rv; 137 ksiginfo_t ksi; 138 139 KASSERT(l == 0 || (l->l_stat == LSONPROC)); 140 141 if (frame->srr1 & PSL_PR) { 142 LWP_CACHE_CREDS(l, p); 143 type |= EXC_USER; 144 } 145 146 ftype = VM_PROT_READ; 147 148 DBPRINTF(TDB_ALL, ("trap(%x) at %lx 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; 155 156 __asm volatile("mfspr %0,0x3f0" : 157 "=r" (rv), "=r" (srr2), "=r" (srr3) :); 158 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, 159 srr3); 160 /* XXX fall through or break here?! */ 161 } 162 /* 163 * DEBUG intr -- probably single-step. 164 */ 165 case EXC_TRC|EXC_USER: 166 frame->srr1 &= ~PSL_SE; 167 KSI_INIT_TRAP(&ksi); 168 ksi.ksi_signo = SIGTRAP; 169 ksi.ksi_trap = EXC_TRC; 170 ksi.ksi_addr = (void *)frame->srr0; 171 trapsignal(l, &ksi); 172 break; 173 174 /* 175 * If we could not find and install appropriate TLB entry, fall through. 176 */ 177 178 case EXC_DSI: 179 /* FALLTHROUGH */ 180 case EXC_DTMISS: 181 { 182 struct vm_map *map; 183 vaddr_t va; 184 struct faultbuf *fb = NULL; 185 186 va = frame->dar; 187 if (frame->tf_xtra[TF_PID] == KERNEL_PID) { 188 map = kernel_map; 189 } else { 190 map = &p->p_vmspace->vm_map; 191 } 192 193 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 194 ftype = VM_PROT_WRITE; 195 196 DBPRINTF(TDB_ALL, 197 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 198 frame->srr0, 199 (ftype & VM_PROT_WRITE) ? "write" : "read", 200 (void *)va, frame->tf_xtra[TF_ESR])); 201 rv = uvm_fault(map, trunc_page(va), ftype); 202 if (rv == 0) 203 goto done; 204 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 205 frame->tf_xtra[TF_PID] = KERNEL_PID; 206 frame->srr0 = fb->fb_pc; 207 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 208 frame->fixreg[1] = fb->fb_sp; 209 frame->fixreg[2] = fb->fb_r2; 210 frame->fixreg[3] = 1; /* Return TRUE */ 211 frame->cr = fb->fb_cr; 212 memcpy(&frame->fixreg[13], fb->fb_fixreg, 213 sizeof(fb->fb_fixreg)); 214 goto done; 215 } 216 } 217 goto brain_damage; 218 219 case EXC_DSI|EXC_USER: 220 /* FALLTHROUGH */ 221 case EXC_DTMISS|EXC_USER: 222 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 223 ftype = VM_PROT_WRITE; 224 225 DBPRINTF(TDB_ALL, 226 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 227 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 228 frame->dar, frame->tf_xtra[TF_ESR])); 229 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 230 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 231 ftype); 232 if (rv == 0) { 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 break; 249 250 case EXC_ITMISS|EXC_USER: 251 case EXC_ISI|EXC_USER: 252 ftype = VM_PROT_EXECUTE; 253 DBPRINTF(TDB_ALL, 254 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 255 frame->srr0, frame)); 256 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 257 ftype); 258 if (rv == 0) { 259 break; 260 } 261 KSI_INIT_TRAP(&ksi); 262 ksi.ksi_signo = SIGSEGV; 263 ksi.ksi_trap = EXC_ISI; 264 ksi.ksi_addr = (void *)frame->srr0; 265 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR); 266 trapsignal(l, &ksi); 267 break; 268 269 case EXC_AST|EXC_USER: 270 curcpu()->ci_astpending = 0; /* we are about to do it */ 271 uvmexp.softs++; 272 if (l->l_pflag & LP_OWEUPC) { 273 l->l_pflag &= ~LP_OWEUPC; 274 ADDUPROF(l); 275 } 276 /* Check whether we are being preempted. */ 277 if (curcpu()->ci_want_resched) 278 preempt(); 279 break; 280 281 282 case EXC_ALI|EXC_USER: 283 if (fix_unaligned(l, frame) != 0) { 284 KSI_INIT_TRAP(&ksi); 285 ksi.ksi_signo = SIGBUS; 286 ksi.ksi_trap = EXC_ALI; 287 ksi.ksi_addr = (void *)frame->dar; 288 trapsignal(l, &ksi); 289 } else 290 frame->srr0 += 4; 291 break; 292 293 case EXC_PGM|EXC_USER: 294 /* 295 * Illegal insn: 296 * 297 * let's try to see if it's FPU and can be emulated. 298 */ 299 uvmexp.traps++; 300 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 301 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 302 sizeof l->l_addr->u_pcb.pcb_fpu); 303 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 304 } 305 306 if ((rv = fpu_emulate(frame, 307 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 308 KSI_INIT_TRAP(&ksi); 309 ksi.ksi_signo = rv; 310 ksi.ksi_trap = EXC_PGM; 311 ksi.ksi_addr = (void *)frame->srr0; 312 trapsignal(l, &ksi); 313 } 314 break; 315 316 case EXC_MCHK: 317 { 318 struct faultbuf *fb; 319 320 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 321 frame->tf_xtra[TF_PID] = KERNEL_PID; 322 frame->srr0 = fb->fb_pc; 323 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 324 frame->fixreg[1] = fb->fb_sp; 325 frame->fixreg[2] = fb->fb_r2; 326 frame->fixreg[3] = 1; /* Return TRUE */ 327 frame->cr = fb->fb_cr; 328 memcpy(&frame->fixreg[13], fb->fb_fixreg, 329 sizeof(fb->fb_fixreg)); 330 goto done; 331 } 332 } 333 goto brain_damage; 334 default: 335 brain_damage: 336 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 337 #if defined(DDB) || defined(KGDB) 338 if (kdb_trap(type, frame)) 339 goto done; 340 #endif 341 #ifdef TRAP_PANICWAIT 342 printf("Press a key to panic.\n"); 343 cngetc(); 344 #endif 345 panic("trap"); 346 } 347 348 /* Invoke MI userret code */ 349 mi_userret(l); 350 done: 351 return; 352 } 353 354 int 355 ctx_setup(int ctx, int srr1) 356 { 357 volatile struct pmap *pm; 358 359 /* Update PID if we're returning to user mode. */ 360 if (srr1 & PSL_PR) { 361 pm = curproc->p_vmspace->vm_map.pmap; 362 if (!pm->pm_ctx) { 363 ctx_alloc(__UNVOLATILE(pm)); 364 } 365 ctx = pm->pm_ctx; 366 if (srr1 & PSL_SE) { 367 int dbreg, mask = 0x48000000; 368 /* 369 * Set the Internal Debug and 370 * Instruction Completion bits of 371 * the DBCR0 register. 372 * 373 * XXX this is also used by jtag debuggers... 374 */ 375 __asm volatile("mfspr %0,0x3f2;" 376 "or %0,%0,%1;" 377 "mtspr 0x3f2,%0;" : 378 "=&r" (dbreg) : "r" (mask)); 379 } 380 } 381 else if (!ctx) { 382 ctx = KERNEL_PID; 383 } 384 return (ctx); 385 } 386 387 /* 388 * Used by copyin()/copyout() 389 */ 390 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 391 extern void vunmaprange __P((vaddr_t, vsize_t)); 392 static int bigcopyin __P((const void *, void *, size_t )); 393 static int bigcopyout __P((const void *, void *, size_t )); 394 395 int 396 copyin(const void *udaddr, void *kaddr, size_t len) 397 { 398 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 399 int msr, pid, tmp, ctx, count=0; 400 struct faultbuf env; 401 402 /* For bigger buffers use the faster copy */ 403 if (len > 1024) 404 return (bigcopyin(udaddr, kaddr, len)); 405 406 if (setfault(&env)) { 407 curpcb->pcb_onfault = 0; 408 return EFAULT; 409 } 410 411 if (!(ctx = pm->pm_ctx)) { 412 /* No context -- assign it one */ 413 ctx_alloc(pm); 414 ctx = pm->pm_ctx; 415 } 416 417 __asm volatile( 418 " mfmsr %[msr];" /* Save MSR */ 419 " li %[pid],0x20; " 420 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ 421 " mfpid %[pid];" /* Save old PID */ 422 " sync; isync;" 423 424 " srwi. %[count],%[len],0x2;" /* How many words? */ 425 " beq- 2f;" /* No words. Go do bytes */ 426 " mtctr %[count];" 427 "1: mtpid %[ctx]; sync;" 428 " lswi %[tmp],%[udaddr],4;" /* Load user word */ 429 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 430 " sync; isync;" 431 " mtpid %[pid];sync;" 432 " stswi %[tmp],%[kaddr],4;" /* Store kernel word */ 433 " dcbf 0,%[kaddr];" /* flush cache */ 434 " addi %[kaddr],%[kaddr],0x4;" /* next udaddr word */ 435 " sync; isync;" 436 " bdnz 1b;" /* repeat */ 437 438 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 439 " addi %[count],%[count],0x1;" 440 " mtctr %[count];" 441 "3: bdz 10f;" /* while count */ 442 " mtpid %[ctx];sync;" 443 " lbz %[tmp],0(%[udaddr]);" /* Load user byte */ 444 " addi %[udaddr],%[udaddr],0x1;" /* next udaddr byte */ 445 " sync; isync;" 446 " mtpid %[pid]; sync;" 447 " stb %[tmp],0(%[kaddr]);" /* Store kernel byte */ 448 " dcbf 0,%[kaddr];" /* flush cache */ 449 " addi %[kaddr],%[kaddr],0x1;" 450 " sync; isync;" 451 " b 3b;" 452 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 453 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 454 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 455 456 curpcb->pcb_onfault = 0; 457 return 0; 458 } 459 460 static int 461 bigcopyin(const void *udaddr, void *kaddr, size_t len) 462 { 463 const char *up; 464 char *kp = kaddr; 465 struct lwp *l = curlwp; 466 struct proc *p; 467 int error; 468 469 if (!l) { 470 return EFAULT; 471 } 472 473 p = l->l_proc; 474 475 /* 476 * Stolen from physio(): 477 */ 478 uvm_lwp_hold(l); 479 error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ); 480 if (error) { 481 uvm_lwp_rele(l); 482 return EFAULT; 483 } 484 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 485 486 memcpy(kp, up, len); 487 vunmaprange((vaddr_t)up, len); 488 uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len); 489 uvm_lwp_rele(l); 490 491 return 0; 492 } 493 494 int 495 copyout(const void *kaddr, void *udaddr, size_t len) 496 { 497 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 498 int msr, pid, tmp, ctx, count=0; 499 struct faultbuf env; 500 501 /* For big copies use more efficient routine */ 502 if (len > 1024) 503 return (bigcopyout(kaddr, udaddr, len)); 504 505 if (setfault(&env)) { 506 curpcb->pcb_onfault = 0; 507 return EFAULT; 508 } 509 510 if (!(ctx = pm->pm_ctx)) { 511 /* No context -- assign it one */ 512 ctx_alloc(pm); 513 ctx = pm->pm_ctx; 514 } 515 516 __asm volatile( 517 " mfmsr %[msr];" /* Save MSR */ \ 518 " li %[pid],0x20; " \ 519 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ \ 520 " mfpid %[pid];" /* Save old PID */ \ 521 " sync; isync;" 522 523 " srwi. %[count],%[len],0x2;" /* How many words? */ 524 " beq- 2f;" /* No words. Go do bytes */ 525 " mtctr %[count];" 526 "1: mtpid %[pid];sync;" 527 " lswi %[tmp],%[kaddr],4;" /* Load kernel word */ 528 " addi %[kaddr],%[kaddr],0x4;" /* next kaddr word */ 529 " sync; isync;" 530 " mtpid %[ctx]; sync;" 531 " stswi %[tmp],%[udaddr],4;" /* Store user word */ 532 " dcbf 0,%[udaddr];" /* flush cache */ 533 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 534 " sync; isync;" 535 " bdnz 1b;" /* repeat */ 536 537 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 538 " addi %[count],%[count],0x1;" 539 " mtctr %[count];" 540 "3: bdz 10f;" /* while count */ 541 " mtpid %[pid];sync;" 542 " lbz %[tmp],0(%[kaddr]);" /* Load kernel byte */ 543 " addi %[kaddr],%[kaddr],0x1;" /* next kaddr byte */ 544 " sync; isync;" 545 " mtpid %[ctx]; sync;" 546 " stb %[tmp],0(%[udaddr]);" /* Store user byte */ 547 " dcbf 0,%[udaddr];" /* flush cache */ 548 " addi %[udaddr],%[udaddr],0x1;" 549 " sync; isync;" 550 " b 3b;" 551 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 552 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 553 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 554 555 curpcb->pcb_onfault = 0; 556 return 0; 557 } 558 559 static int 560 bigcopyout(const void *kaddr, void *udaddr, size_t len) 561 { 562 char *up; 563 const char *kp = (const char *)kaddr; 564 struct lwp *l = curlwp; 565 struct proc *p; 566 int error; 567 568 if (!l) { 569 return EFAULT; 570 } 571 572 p = l->l_proc; 573 574 /* 575 * Stolen from physio(): 576 */ 577 uvm_lwp_hold(l); 578 error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE); 579 if (error) { 580 uvm_lwp_rele(l); 581 return EFAULT; 582 } 583 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 584 VM_PROT_READ | VM_PROT_WRITE); 585 586 memcpy(up, kp, len); 587 vunmaprange((vaddr_t)up, len); 588 uvm_vsunlock(p->p_vmspace, udaddr, len); 589 uvm_lwp_rele(l); 590 591 return 0; 592 } 593 594 /* 595 * kcopy(const void *src, void *dst, size_t len); 596 * 597 * Copy len bytes from src to dst, aborting if we encounter a fatal 598 * page fault. 599 * 600 * kcopy() _must_ save and restore the old fault handler since it is 601 * called by uiomove(), which may be in the path of servicing a non-fatal 602 * page fault. 603 */ 604 int 605 kcopy(const void *src, void *dst, size_t len) 606 { 607 struct faultbuf env, *oldfault; 608 609 oldfault = curpcb->pcb_onfault; 610 if (setfault(&env)) { 611 curpcb->pcb_onfault = oldfault; 612 return EFAULT; 613 } 614 615 memcpy(dst, src, len); 616 617 curpcb->pcb_onfault = oldfault; 618 return 0; 619 } 620 621 int 622 badaddr(void *addr, size_t size) 623 { 624 625 return badaddr_read(addr, size, NULL); 626 } 627 628 int 629 badaddr_read(void *addr, size_t size, int *rptr) 630 { 631 struct faultbuf env; 632 int x; 633 634 /* Get rid of any stale machine checks that have been waiting. */ 635 __asm volatile ("sync; isync"); 636 637 if (setfault(&env)) { 638 curpcb->pcb_onfault = 0; 639 __asm volatile ("sync"); 640 return 1; 641 } 642 643 __asm volatile ("sync"); 644 645 switch (size) { 646 case 1: 647 x = *(volatile int8_t *)addr; 648 break; 649 case 2: 650 x = *(volatile int16_t *)addr; 651 break; 652 case 4: 653 x = *(volatile int32_t *)addr; 654 break; 655 default: 656 panic("badaddr: invalid size (%d)", size); 657 } 658 659 /* Make sure we took the machine check, if we caused one. */ 660 __asm volatile ("sync; isync"); 661 662 curpcb->pcb_onfault = 0; 663 __asm volatile ("sync"); /* To be sure. */ 664 665 /* Use the value to avoid reorder. */ 666 if (rptr) 667 *rptr = x; 668 669 return 0; 670 } 671 672 /* 673 * For now, this only deals with the particular unaligned access case 674 * that gcc tends to generate. Eventually it should handle all of the 675 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 676 */ 677 678 static int 679 fix_unaligned(struct lwp *l, struct trapframe *frame) 680 { 681 682 return -1; 683 } 684 685 /* 686 * Start a new LWP 687 */ 688 void 689 startlwp(arg) 690 void *arg; 691 { 692 int err; 693 ucontext_t *uc = arg; 694 struct lwp *l = curlwp; 695 696 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 697 #if DIAGNOSTIC 698 if (err) { 699 printf("Error %d from cpu_setmcontext.", err); 700 } 701 #endif 702 pool_put(&lwp_uc_pool, uc); 703 704 /* Invoke MI userret code */ 705 mi_userret(l); 706 } 707
Indexes created Tue Sep 30 20:09:53 GMT 2025