trap.c revision 1.67
1 /* $NetBSD: trap.c,v 1.67 2014/10/18 08:33:26 snj 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 1.67 2014/10/18 08:33:26 snj 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/userret.h> 82 #include <sys/kauth.h> 83 #include <sys/cpu.h> 84 85 #if defined(KGDB) 86 #include <sys/kgdb.h> 87 #endif 88 89 #include <uvm/uvm_extern.h> 90 91 #include <dev/cons.h> 92 93 #include <machine/fpu.h> 94 #include <machine/frame.h> 95 #include <machine/pcb.h> 96 #include <machine/psl.h> 97 #include <machine/trap.h> 98 99 #include <powerpc/db_machdep.h> 100 #include <powerpc/spr.h> 101 #include <powerpc/ibm4xx/spr.h> 102 103 #include <powerpc/ibm4xx/cpu.h> 104 #include <powerpc/ibm4xx/pmap.h> 105 #include <powerpc/ibm4xx/tlb.h> 106 107 #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(struct lwp *l, struct trapframe *tf); 115 116 void trap(struct trapframe *); /* Called from locore / trap_subr */ 117 /* Why are these not defined in a header? */ 118 int badaddr(void *, size_t); 119 int badaddr_read(void *, size_t, int *); 120 int ctx_setup(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 *tf) 132 { 133 struct lwp *l = curlwp; 134 struct proc *p = l->l_proc; 135 struct pcb *pcb; 136 int type = tf->tf_exc; 137 int ftype, rv; 138 ksiginfo_t ksi; 139 140 KASSERT(l->l_stat == LSONPROC); 141 142 if (tf->tf_srr1 & PSL_PR) { 143 LWP_CACHE_CREDS(l, p); 144 type |= EXC_USER; 145 } 146 147 ftype = VM_PROT_READ; 148 149 DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n", 150 type, tf->tf_srr0, tf, &tf)); 151 152 switch (type) { 153 case EXC_DEBUG|EXC_USER: 154 { 155 int srr2, srr3; 156 157 __asm volatile("mfspr %0,0x3f0" : 158 "=r" (rv), "=r" (srr2), "=r" (srr3) :); 159 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, 160 srr3); 161 /* XXX fall through or break here?! */ 162 } 163 /* 164 * DEBUG intr -- probably single-step. 165 */ 166 case EXC_TRC|EXC_USER: 167 tf->tf_srr1 &= ~PSL_SE; 168 KSI_INIT_TRAP(&ksi); 169 ksi.ksi_signo = SIGTRAP; 170 ksi.ksi_trap = EXC_TRC; 171 ksi.ksi_addr = (void *)tf->tf_srr0; 172 trapsignal(l, &ksi); 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 va = tf->tf_dear; 188 if (tf->tf_pid == KERNEL_PID) { 189 map = kernel_map; 190 } else { 191 map = &p->p_vmspace->vm_map; 192 } 193 194 if (tf->tf_esr & (ESR_DST|ESR_DIZ)) 195 ftype = VM_PROT_WRITE; 196 197 DBPRINTF(TDB_ALL, 198 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 199 tf->tf_srr0, 200 (ftype & VM_PROT_WRITE) ? "write" : "read", 201 (void *)va, tf->tf_esr)); 202 203 pcb = lwp_getpcb(l); 204 fb = pcb->pcb_onfault; 205 pcb->pcb_onfault = NULL; 206 rv = uvm_fault(map, trunc_page(va), ftype); 207 pcb->pcb_onfault = fb; 208 if (rv == 0) 209 goto done; 210 if (fb != NULL) { 211 tf->tf_pid = KERNEL_PID; 212 tf->tf_srr0 = fb->fb_pc; 213 tf->tf_srr1 |= PSL_IR; /* Re-enable IMMU */ 214 tf->tf_cr = fb->fb_cr; 215 tf->tf_fixreg[1] = fb->fb_sp; 216 tf->tf_fixreg[2] = fb->fb_r2; 217 tf->tf_fixreg[3] = 1; /* Return TRUE */ 218 memcpy(&tf->tf_fixreg[13], fb->fb_fixreg, 219 sizeof(fb->fb_fixreg)); 220 goto done; 221 } 222 } 223 goto brain_damage; 224 225 case EXC_DSI|EXC_USER: 226 /* FALLTHROUGH */ 227 case EXC_DTMISS|EXC_USER: 228 if (tf->tf_esr & (ESR_DST|ESR_DIZ)) 229 ftype = VM_PROT_WRITE; 230 231 DBPRINTF(TDB_ALL, 232 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 233 tf->tf_srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 234 tf->tf_dear, tf->tf_esr)); 235 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 236 // KASSERT(curpcb->pcb_onfault == NULL); 237 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(tf->tf_dear), 238 ftype); 239 if (rv == 0) { 240 break; 241 } 242 KSI_INIT_TRAP(&ksi); 243 ksi.ksi_signo = SIGSEGV; 244 ksi.ksi_trap = EXC_DSI; 245 ksi.ksi_addr = (void *)tf->tf_dear; 246 if (rv == ENOMEM) { 247 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 248 "out of swap\n", 249 p->p_pid, p->p_comm, l->l_lid, 250 l->l_cred ? 251 kauth_cred_geteuid(l->l_cred) : -1); 252 ksi.ksi_signo = SIGKILL; 253 } 254 trapsignal(l, &ksi); 255 break; 256 257 case EXC_ITMISS|EXC_USER: 258 case EXC_ISI|EXC_USER: 259 ftype = VM_PROT_EXECUTE; 260 DBPRINTF(TDB_ALL, 261 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 262 tf->tf_srr0, tf)); 263 // KASSERT(curpcb->pcb_onfault == NULL); 264 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(tf->tf_srr0), 265 ftype); 266 if (rv == 0) { 267 break; 268 } 269 KSI_INIT_TRAP(&ksi); 270 ksi.ksi_signo = SIGSEGV; 271 ksi.ksi_trap = EXC_ISI; 272 ksi.ksi_addr = (void *)tf->tf_srr0; 273 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR); 274 trapsignal(l, &ksi); 275 break; 276 277 case EXC_AST|EXC_USER: 278 cpu_ast(l, curcpu()); 279 break; 280 281 case EXC_ALI|EXC_USER: 282 if (fix_unaligned(l, tf) != 0) { 283 KSI_INIT_TRAP(&ksi); 284 ksi.ksi_signo = SIGBUS; 285 ksi.ksi_trap = EXC_ALI; 286 ksi.ksi_addr = (void *)tf->tf_dear; 287 trapsignal(l, &ksi); 288 } else 289 tf->tf_srr0 += 4; 290 break; 291 292 case EXC_PGM|EXC_USER: 293 /* 294 * Illegal insn: 295 * 296 * let's try to see if its FPU and can be emulated. 297 */ 298 curcpu()->ci_data.cpu_ntrap++; 299 pcb = lwp_getpcb(l); 300 301 if (__predict_false(!fpu_used_p(l))) { 302 memset(&pcb->pcb_fpu, 0, sizeof(pcb->pcb_fpu)); 303 fpu_mark_used(l); 304 } 305 306 if (fpu_emulate(tf, &pcb->pcb_fpu, &ksi)) { 307 if (ksi.ksi_signo == 0) /* was emulated */ 308 break; 309 } else { 310 ksi.ksi_signo = SIGILL; 311 ksi.ksi_code = ILL_ILLOPC; 312 ksi.ksi_trap = EXC_PGM; 313 ksi.ksi_addr = (void *)tf->tf_srr0; 314 } 315 316 trapsignal(l, &ksi); 317 break; 318 319 case EXC_MCHK: 320 { 321 struct faultbuf *fb; 322 323 pcb = lwp_getpcb(l); 324 if ((fb = pcb->pcb_onfault) != NULL) { 325 tf->tf_pid = KERNEL_PID; 326 tf->tf_srr0 = fb->fb_pc; 327 tf->tf_srr1 |= PSL_IR; /* Re-enable IMMU */ 328 tf->tf_fixreg[1] = fb->fb_sp; 329 tf->tf_fixreg[2] = fb->fb_r2; 330 tf->tf_fixreg[3] = 1; /* Return TRUE */ 331 tf->tf_cr = fb->fb_cr; 332 memcpy(&tf->tf_fixreg[13], fb->fb_fixreg, 333 sizeof(fb->fb_fixreg)); 334 goto done; 335 } 336 } 337 goto brain_damage; 338 default: 339 brain_damage: 340 printf("trap type 0x%x at 0x%lx\n", type, tf->tf_srr0); 341 #if defined(DDB) || defined(KGDB) 342 if (kdb_trap(type, tf)) 343 goto done; 344 #endif 345 #ifdef TRAP_PANICWAIT 346 printf("Press a key to panic.\n"); 347 cngetc(); 348 #endif 349 panic("trap"); 350 } 351 352 /* Invoke MI userret code */ 353 mi_userret(l); 354 done: 355 return; 356 } 357 358 int 359 ctx_setup(int ctx, int srr1) 360 { 361 volatile struct pmap *pm; 362 363 /* Update PID if we're returning to user mode. */ 364 if (srr1 & PSL_PR) { 365 pm = curproc->p_vmspace->vm_map.pmap; 366 if (!pm->pm_ctx) { 367 ctx_alloc(__UNVOLATILE(pm)); 368 } 369 ctx = pm->pm_ctx; 370 if (srr1 & PSL_SE) { 371 int dbreg, mask = 0x48000000; 372 /* 373 * Set the Internal Debug and 374 * Instruction Completion bits of 375 * the DBCR0 register. 376 * 377 * XXX this is also used by jtag debuggers... 378 */ 379 __asm volatile("mfspr %0,0x3f2;" 380 "or %0,%0,%1;" 381 "mtspr 0x3f2,%0;" : 382 "=&r" (dbreg) : "r" (mask)); 383 } 384 } 385 else if (!ctx) { 386 ctx = KERNEL_PID; 387 } 388 return (ctx); 389 } 390 391 /* 392 * Used by copyin()/copyout() 393 */ 394 extern vaddr_t vmaprange(struct proc *, vaddr_t, vsize_t, int); 395 extern void vunmaprange(vaddr_t, vsize_t); 396 static int bigcopyin(const void *, void *, size_t ); 397 static int bigcopyout(const void *, void *, size_t ); 398 399 int 400 copyin(const void *udaddr, void *kaddr, size_t len) 401 { 402 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 403 int rv, msr, pid, tmp, ctx, count = 0; 404 struct faultbuf env; 405 406 /* For bigger buffers use the faster copy */ 407 if (len > 1024) 408 return (bigcopyin(udaddr, kaddr, len)); 409 410 if ((rv = setfault(&env))) { 411 curpcb->pcb_onfault = NULL; 412 return rv; 413 } 414 415 if (!(ctx = pm->pm_ctx)) { 416 /* No context -- assign it one */ 417 ctx_alloc(pm); 418 ctx = pm->pm_ctx; 419 } 420 421 __asm volatile( 422 " mfmsr %[msr];" /* Save MSR */ 423 " li %[pid],0x20; " 424 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ 425 " mfpid %[pid];" /* Save old PID */ 426 " sync; isync;" 427 428 " srwi. %[count],%[len],0x2;" /* How many words? */ 429 " beq- 2f;" /* No words. Go do bytes */ 430 " mtctr %[count];" 431 "1: mtpid %[ctx]; sync;" 432 " lswi %[tmp],%[udaddr],4;" /* Load user word */ 433 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 434 " sync; isync;" 435 " mtpid %[pid];sync;" 436 " stswi %[tmp],%[kaddr],4;" /* Store kernel word */ 437 " dcbf 0,%[kaddr];" /* flush cache */ 438 " addi %[kaddr],%[kaddr],0x4;" /* next udaddr word */ 439 " sync; isync;" 440 " bdnz 1b;" /* repeat */ 441 442 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 443 " addi %[count],%[count],0x1;" 444 " mtctr %[count];" 445 "3: bdz 10f;" /* while count */ 446 " mtpid %[ctx];sync;" 447 " lbz %[tmp],0(%[udaddr]);" /* Load user byte */ 448 " addi %[udaddr],%[udaddr],0x1;" /* next udaddr byte */ 449 " sync; isync;" 450 " mtpid %[pid]; sync;" 451 " stb %[tmp],0(%[kaddr]);" /* Store kernel byte */ 452 " dcbf 0,%[kaddr];" /* flush cache */ 453 " addi %[kaddr],%[kaddr],0x1;" 454 " sync; isync;" 455 " b 3b;" 456 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 457 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 458 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 459 460 curpcb->pcb_onfault = NULL; 461 return 0; 462 } 463 464 static int 465 bigcopyin(const void *udaddr, void *kaddr, size_t len) 466 { 467 const char *up; 468 char *kp = kaddr; 469 struct lwp *l = curlwp; 470 struct proc *p; 471 struct faultbuf env; 472 int error; 473 474 p = l->l_proc; 475 476 /* 477 * Stolen from physio(): 478 */ 479 error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ); 480 if (error) { 481 return error; 482 } 483 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 484 485 if ((error = setfault(&env)) == 0) { 486 memcpy(kp, up, len); 487 } 488 489 curpcb->pcb_onfault = NULL; 490 vunmaprange((vaddr_t)up, len); 491 uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len); 492 493 return error; 494 } 495 496 int 497 copyout(const void *kaddr, void *udaddr, size_t len) 498 { 499 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 500 int rv, msr, pid, tmp, ctx, count = 0; 501 struct faultbuf env; 502 503 /* For big copies use more efficient routine */ 504 if (len > 1024) 505 return (bigcopyout(kaddr, udaddr, len)); 506 507 if ((rv = setfault(&env))) { 508 curpcb->pcb_onfault = NULL; 509 return rv; 510 } 511 512 if (!(ctx = pm->pm_ctx)) { 513 /* No context -- assign it one */ 514 ctx_alloc(pm); 515 ctx = pm->pm_ctx; 516 } 517 518 __asm volatile( 519 " mfmsr %[msr];" /* Save MSR */ \ 520 " li %[pid],0x20; " \ 521 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ \ 522 " mfpid %[pid];" /* Save old PID */ \ 523 " sync; isync;" 524 525 " srwi. %[count],%[len],0x2;" /* How many words? */ 526 " beq- 2f;" /* No words. Go do bytes */ 527 " mtctr %[count];" 528 "1: mtpid %[pid];sync;" 529 " lswi %[tmp],%[kaddr],4;" /* Load kernel word */ 530 " addi %[kaddr],%[kaddr],0x4;" /* next kaddr word */ 531 " sync; isync;" 532 " mtpid %[ctx]; sync;" 533 " stswi %[tmp],%[udaddr],4;" /* Store user word */ 534 " dcbf 0,%[udaddr];" /* flush cache */ 535 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 536 " sync; isync;" 537 " bdnz 1b;" /* repeat */ 538 539 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 540 " addi %[count],%[count],0x1;" 541 " mtctr %[count];" 542 "3: bdz 10f;" /* while count */ 543 " mtpid %[pid];sync;" 544 " lbz %[tmp],0(%[kaddr]);" /* Load kernel byte */ 545 " addi %[kaddr],%[kaddr],0x1;" /* next kaddr byte */ 546 " sync; isync;" 547 " mtpid %[ctx]; sync;" 548 " stb %[tmp],0(%[udaddr]);" /* Store user byte */ 549 " dcbf 0,%[udaddr];" /* flush cache */ 550 " addi %[udaddr],%[udaddr],0x1;" 551 " sync; isync;" 552 " b 3b;" 553 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 554 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 555 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 556 557 curpcb->pcb_onfault = NULL; 558 return 0; 559 } 560 561 static int 562 bigcopyout(const void *kaddr, void *udaddr, size_t len) 563 { 564 char *up; 565 const char *kp = (const char *)kaddr; 566 struct lwp *l = curlwp; 567 struct proc *p; 568 struct faultbuf env; 569 int error; 570 571 p = l->l_proc; 572 573 /* 574 * Stolen from physio(): 575 */ 576 error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE); 577 if (error) { 578 return error; 579 } 580 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 581 VM_PROT_READ | VM_PROT_WRITE); 582 583 if ((error = setfault(&env)) == 0) { 584 memcpy(up, kp, len); 585 } 586 587 curpcb->pcb_onfault = NULL; 588 vunmaprange((vaddr_t)up, len); 589 uvm_vsunlock(p->p_vmspace, udaddr, len); 590 591 return error; 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 int rv; 609 610 oldfault = curpcb->pcb_onfault; 611 if ((rv = setfault(&env))) { 612 curpcb->pcb_onfault = oldfault; 613 return rv; 614 } 615 616 memcpy(dst, src, len); 617 618 curpcb->pcb_onfault = oldfault; 619 return 0; 620 } 621 622 int 623 badaddr(void *addr, size_t size) 624 { 625 626 return badaddr_read(addr, size, NULL); 627 } 628 629 int 630 badaddr_read(void *addr, size_t size, int *rptr) 631 { 632 struct faultbuf env; 633 int x; 634 635 /* Get rid of any stale machine checks that have been waiting. */ 636 __asm volatile ("sync; isync"); 637 638 if (setfault(&env)) { 639 curpcb->pcb_onfault = NULL; 640 __asm volatile ("sync"); 641 return 1; 642 } 643 644 __asm volatile ("sync"); 645 646 switch (size) { 647 case 1: 648 x = *(volatile int8_t *)addr; 649 break; 650 case 2: 651 x = *(volatile int16_t *)addr; 652 break; 653 case 4: 654 x = *(volatile int32_t *)addr; 655 break; 656 default: 657 panic("badaddr: invalid size (%d)", size); 658 } 659 660 /* Make sure we took the machine check, if we caused one. */ 661 __asm volatile ("sync; isync"); 662 663 curpcb->pcb_onfault = NULL; 664 __asm volatile ("sync"); /* To be sure. */ 665 666 /* Use the value to avoid reorder. */ 667 if (rptr) 668 *rptr = x; 669 670 return 0; 671 } 672 673 /* 674 * For now, this only deals with the particular unaligned access case 675 * that gcc tends to generate. Eventually it should handle all of the 676 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 677 */ 678 679 static int 680 fix_unaligned(struct lwp *l, struct trapframe *tf) 681 { 682 683 return -1; 684 } 685
Indexes created Mon Sep 22 13:09:51 GMT 2025