trap.c revision 1.69
1 /* $NetBSD: trap.c,v 1.69 2016/12/26 21:54:00 rin 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 1.69 2016/12/26 21:54:00 rin 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 case EXC_DSI: 176 /* FALLTHROUGH */ 177 case EXC_DTMISS: 178 { 179 struct vm_map *map; 180 vaddr_t va; 181 struct faultbuf *fb = NULL; 182 183 va = tf->tf_dear; 184 if (tf->tf_pid == KERNEL_PID) { 185 map = kernel_map; 186 } else { 187 map = &p->p_vmspace->vm_map; 188 } 189 190 if (tf->tf_esr & (ESR_DST|ESR_DIZ)) 191 ftype = VM_PROT_WRITE; 192 193 DBPRINTF(TDB_ALL, 194 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 195 tf->tf_srr0, 196 (ftype & VM_PROT_WRITE) ? "write" : "read", 197 (void *)va, tf->tf_esr)); 198 199 pcb = lwp_getpcb(l); 200 fb = pcb->pcb_onfault; 201 pcb->pcb_onfault = NULL; 202 rv = uvm_fault(map, trunc_page(va), ftype); 203 pcb->pcb_onfault = fb; 204 if (rv == 0) 205 return; 206 if (fb != NULL) { 207 tf->tf_pid = KERNEL_PID; 208 tf->tf_srr0 = fb->fb_pc; 209 tf->tf_srr1 |= PSL_IR; /* Re-enable IMMU */ 210 tf->tf_cr = fb->fb_cr; 211 tf->tf_fixreg[1] = fb->fb_sp; 212 tf->tf_fixreg[2] = fb->fb_r2; 213 tf->tf_fixreg[3] = 1; /* Return TRUE */ 214 memcpy(&tf->tf_fixreg[13], fb->fb_fixreg, 215 sizeof(fb->fb_fixreg)); 216 return; 217 } 218 } 219 goto brain_damage; 220 221 case EXC_DSI|EXC_USER: 222 /* FALLTHROUGH */ 223 case EXC_DTMISS|EXC_USER: 224 if (tf->tf_esr & (ESR_DST|ESR_DIZ)) 225 ftype = VM_PROT_WRITE; 226 227 DBPRINTF(TDB_ALL, 228 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 229 tf->tf_srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 230 tf->tf_dear, tf->tf_esr)); 231 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 232 // KASSERT(curpcb->pcb_onfault == NULL); 233 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(tf->tf_dear), 234 ftype); 235 if (rv == 0) { 236 break; 237 } 238 KSI_INIT_TRAP(&ksi); 239 ksi.ksi_signo = SIGSEGV; 240 ksi.ksi_trap = EXC_DSI; 241 ksi.ksi_addr = (void *)tf->tf_dear; 242 if (rv == ENOMEM) { 243 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 244 "out of swap\n", 245 p->p_pid, p->p_comm, l->l_lid, 246 l->l_cred ? 247 kauth_cred_geteuid(l->l_cred) : -1); 248 ksi.ksi_signo = SIGKILL; 249 } 250 trapsignal(l, &ksi); 251 break; 252 253 case EXC_ITMISS|EXC_USER: 254 case EXC_ISI|EXC_USER: 255 ftype = VM_PROT_EXECUTE; 256 DBPRINTF(TDB_ALL, 257 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 258 tf->tf_srr0, tf)); 259 // KASSERT(curpcb->pcb_onfault == NULL); 260 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(tf->tf_srr0), 261 ftype); 262 if (rv == 0) { 263 break; 264 } 265 KSI_INIT_TRAP(&ksi); 266 ksi.ksi_signo = SIGSEGV; 267 ksi.ksi_trap = EXC_ISI; 268 ksi.ksi_addr = (void *)tf->tf_srr0; 269 ksi.ksi_code = (rv == EACCES ? SEGV_ACCERR : SEGV_MAPERR); 270 trapsignal(l, &ksi); 271 break; 272 273 case EXC_AST|EXC_USER: 274 cpu_ast(l, curcpu()); 275 break; 276 277 case EXC_ALI|EXC_USER: 278 if (fix_unaligned(l, tf) != 0) { 279 KSI_INIT_TRAP(&ksi); 280 ksi.ksi_signo = SIGBUS; 281 ksi.ksi_trap = EXC_ALI; 282 ksi.ksi_addr = (void *)tf->tf_dear; 283 trapsignal(l, &ksi); 284 } else 285 tf->tf_srr0 += 4; 286 break; 287 288 case EXC_PGM|EXC_USER: 289 /* 290 * Illegal insn: 291 * 292 * let's try to see if its FPU and can be emulated. 293 */ 294 curcpu()->ci_data.cpu_ntrap++; 295 pcb = lwp_getpcb(l); 296 297 if (__predict_false(!fpu_used_p(l))) { 298 memset(&pcb->pcb_fpu, 0, sizeof(pcb->pcb_fpu)); 299 fpu_mark_used(l); 300 } 301 302 if (fpu_emulate(tf, &pcb->pcb_fpu, &ksi)) { 303 if (ksi.ksi_signo == 0) /* was emulated */ 304 break; 305 } else { 306 ksi.ksi_signo = SIGILL; 307 ksi.ksi_code = ILL_ILLOPC; 308 ksi.ksi_trap = EXC_PGM; 309 ksi.ksi_addr = (void *)tf->tf_srr0; 310 } 311 312 trapsignal(l, &ksi); 313 break; 314 315 case EXC_MCHK: 316 { 317 struct faultbuf *fb; 318 319 pcb = lwp_getpcb(l); 320 if ((fb = pcb->pcb_onfault) != NULL) { 321 tf->tf_pid = KERNEL_PID; 322 tf->tf_srr0 = fb->fb_pc; 323 tf->tf_srr1 |= PSL_IR; /* Re-enable IMMU */ 324 tf->tf_fixreg[1] = fb->fb_sp; 325 tf->tf_fixreg[2] = fb->fb_r2; 326 tf->tf_fixreg[3] = 1; /* Return TRUE */ 327 tf->tf_cr = fb->fb_cr; 328 memcpy(&tf->tf_fixreg[13], fb->fb_fixreg, 329 sizeof(fb->fb_fixreg)); 330 return; 331 } 332 } 333 goto brain_damage; 334 335 default: 336 brain_damage: 337 printf("trap type 0x%x at 0x%lx\n", type, tf->tf_srr0); 338 #if defined(DDB) || defined(KGDB) 339 if (kdb_trap(type, tf)) 340 return; 341 #endif 342 #ifdef TRAP_PANICWAIT 343 printf("Press a key to panic.\n"); 344 cngetc(); 345 #endif 346 panic("trap"); 347 } 348 349 /* Invoke MI userret code */ 350 mi_userret(l); 351 } 352 353 int 354 ctx_setup(int ctx, int srr1) 355 { 356 volatile struct pmap *pm; 357 358 /* Update PID if we're returning to user mode. */ 359 if (srr1 & PSL_PR) { 360 pm = curproc->p_vmspace->vm_map.pmap; 361 if (!pm->pm_ctx) { 362 ctx_alloc(__UNVOLATILE(pm)); 363 } 364 ctx = pm->pm_ctx; 365 if (srr1 & PSL_SE) { 366 int dbreg, mask = 0x48000000; 367 /* 368 * Set the Internal Debug and 369 * Instruction Completion bits of 370 * the DBCR0 register. 371 * 372 * XXX this is also used by jtag debuggers... 373 */ 374 __asm volatile("mfspr %0,0x3f2;" 375 "or %0,%0,%1;" 376 "mtspr 0x3f2,%0;" : 377 "=&r" (dbreg) : "r" (mask)); 378 } 379 } 380 else if (!ctx) { 381 ctx = KERNEL_PID; 382 } 383 return (ctx); 384 } 385 386 /* 387 * Used by copyin()/copyout() 388 */ 389 extern vaddr_t vmaprange(struct proc *, vaddr_t, vsize_t, int); 390 extern void vunmaprange(vaddr_t, vsize_t); 391 static int bigcopyin(const void *, void *, size_t ); 392 static int bigcopyout(const void *, void *, size_t ); 393 394 int 395 copyin(const void *udaddr, void *kaddr, size_t len) 396 { 397 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 398 int rv, msr, pid, tmp, ctx, count = 0; 399 struct faultbuf env; 400 401 /* For bigger buffers use the faster copy */ 402 if (len > 1024) 403 return (bigcopyin(udaddr, kaddr, len)); 404 405 if ((rv = setfault(&env))) { 406 curpcb->pcb_onfault = NULL; 407 return rv; 408 } 409 410 if (!(ctx = pm->pm_ctx)) { 411 /* No context -- assign it one */ 412 ctx_alloc(pm); 413 ctx = pm->pm_ctx; 414 } 415 416 __asm volatile( 417 " mfmsr %[msr];" /* Save MSR */ 418 " li %[pid],0x20; " 419 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ 420 " mfpid %[pid];" /* Save old PID */ 421 " sync; isync;" 422 423 " srwi. %[count],%[len],0x2;" /* How many words? */ 424 " beq- 2f;" /* No words. Go do bytes */ 425 " mtctr %[count];" 426 "1: mtpid %[ctx]; sync;" 427 " lswi %[tmp],%[udaddr],4;" /* Load user word */ 428 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 429 " sync; isync;" 430 " mtpid %[pid];sync;" 431 " stswi %[tmp],%[kaddr],4;" /* Store kernel word */ 432 " dcbf 0,%[kaddr];" /* flush cache */ 433 " addi %[kaddr],%[kaddr],0x4;" /* next udaddr word */ 434 " sync; isync;" 435 " bdnz 1b;" /* repeat */ 436 437 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 438 " addi %[count],%[count],0x1;" 439 " mtctr %[count];" 440 "3: bdz 10f;" /* while count */ 441 " mtpid %[ctx];sync;" 442 " lbz %[tmp],0(%[udaddr]);" /* Load user byte */ 443 " addi %[udaddr],%[udaddr],0x1;" /* next udaddr byte */ 444 " sync; isync;" 445 " mtpid %[pid]; sync;" 446 " stb %[tmp],0(%[kaddr]);" /* Store kernel byte */ 447 " dcbf 0,%[kaddr];" /* flush cache */ 448 " addi %[kaddr],%[kaddr],0x1;" 449 " sync; isync;" 450 " b 3b;" 451 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 452 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 453 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 454 455 curpcb->pcb_onfault = NULL; 456 return 0; 457 } 458 459 static int 460 bigcopyin(const void *udaddr, void *kaddr, size_t len) 461 { 462 const char *up; 463 char *kp = kaddr; 464 struct lwp *l = curlwp; 465 struct proc *p; 466 struct faultbuf env; 467 int error; 468 469 p = l->l_proc; 470 471 /* 472 * Stolen from physio(): 473 */ 474 error = uvm_vslock(p->p_vmspace, __UNCONST(udaddr), len, VM_PROT_READ); 475 if (error) { 476 return error; 477 } 478 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 479 480 if ((error = setfault(&env)) == 0) { 481 memcpy(kp, up, len); 482 } 483 484 curpcb->pcb_onfault = NULL; 485 vunmaprange((vaddr_t)up, len); 486 uvm_vsunlock(p->p_vmspace, __UNCONST(udaddr), len); 487 488 return error; 489 } 490 491 int 492 copyout(const void *kaddr, void *udaddr, size_t len) 493 { 494 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 495 int rv, msr, pid, tmp, ctx, count = 0; 496 struct faultbuf env; 497 498 /* For big copies use more efficient routine */ 499 if (len > 1024) 500 return (bigcopyout(kaddr, udaddr, len)); 501 502 if ((rv = setfault(&env))) { 503 curpcb->pcb_onfault = NULL; 504 return rv; 505 } 506 507 if (!(ctx = pm->pm_ctx)) { 508 /* No context -- assign it one */ 509 ctx_alloc(pm); 510 ctx = pm->pm_ctx; 511 } 512 513 __asm volatile( 514 " mfmsr %[msr];" /* Save MSR */ \ 515 " li %[pid],0x20; " \ 516 " andc %[pid],%[msr],%[pid]; mtmsr %[pid];" /* Disable IMMU */ \ 517 " mfpid %[pid];" /* Save old PID */ \ 518 " sync; isync;" 519 520 " srwi. %[count],%[len],0x2;" /* How many words? */ 521 " beq- 2f;" /* No words. Go do bytes */ 522 " mtctr %[count];" 523 "1: mtpid %[pid];sync;" 524 " lswi %[tmp],%[kaddr],4;" /* Load kernel word */ 525 " addi %[kaddr],%[kaddr],0x4;" /* next kaddr word */ 526 " sync; isync;" 527 " mtpid %[ctx]; sync;" 528 " stswi %[tmp],%[udaddr],4;" /* Store user word */ 529 " dcbf 0,%[udaddr];" /* flush cache */ 530 " addi %[udaddr],%[udaddr],0x4;" /* next udaddr word */ 531 " sync; isync;" 532 " bdnz 1b;" /* repeat */ 533 534 "2: andi. %[count],%[len],0x3;" /* How many remaining bytes? */ 535 " addi %[count],%[count],0x1;" 536 " mtctr %[count];" 537 "3: bdz 10f;" /* while count */ 538 " mtpid %[pid];sync;" 539 " lbz %[tmp],0(%[kaddr]);" /* Load kernel byte */ 540 " addi %[kaddr],%[kaddr],0x1;" /* next kaddr byte */ 541 " sync; isync;" 542 " mtpid %[ctx]; sync;" 543 " stb %[tmp],0(%[udaddr]);" /* Store user byte */ 544 " dcbf 0,%[udaddr];" /* flush cache */ 545 " addi %[udaddr],%[udaddr],0x1;" 546 " sync; isync;" 547 " b 3b;" 548 "10:mtpid %[pid]; mtmsr %[msr]; sync; isync;" /* Restore PID and MSR */ 549 : [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp) 550 : [udaddr] "b" (udaddr), [ctx] "b" (ctx), [kaddr] "b" (kaddr), [len] "b" (len), [count] "b" (count)); 551 552 curpcb->pcb_onfault = NULL; 553 return 0; 554 } 555 556 static int 557 bigcopyout(const void *kaddr, void *udaddr, size_t len) 558 { 559 char *up; 560 const char *kp = (const char *)kaddr; 561 struct lwp *l = curlwp; 562 struct proc *p; 563 struct faultbuf env; 564 int error; 565 566 p = l->l_proc; 567 568 /* 569 * Stolen from physio(): 570 */ 571 error = uvm_vslock(p->p_vmspace, udaddr, len, VM_PROT_WRITE); 572 if (error) { 573 return error; 574 } 575 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 576 VM_PROT_READ | VM_PROT_WRITE); 577 578 if ((error = setfault(&env)) == 0) { 579 memcpy(up, kp, len); 580 } 581 582 curpcb->pcb_onfault = NULL; 583 vunmaprange((vaddr_t)up, len); 584 uvm_vsunlock(p->p_vmspace, udaddr, len); 585 586 return error; 587 } 588 589 /* 590 * kcopy(const void *src, void *dst, size_t len); 591 * 592 * Copy len bytes from src to dst, aborting if we encounter a fatal 593 * page fault. 594 * 595 * kcopy() _must_ save and restore the old fault handler since it is 596 * called by uiomove(), which may be in the path of servicing a non-fatal 597 * page fault. 598 */ 599 int 600 kcopy(const void *src, void *dst, size_t len) 601 { 602 struct faultbuf env, *oldfault; 603 int rv; 604 605 oldfault = curpcb->pcb_onfault; 606 if ((rv = setfault(&env))) { 607 curpcb->pcb_onfault = oldfault; 608 return rv; 609 } 610 611 memcpy(dst, src, len); 612 613 curpcb->pcb_onfault = oldfault; 614 return 0; 615 } 616 617 int 618 badaddr(void *addr, size_t size) 619 { 620 621 return badaddr_read(addr, size, NULL); 622 } 623 624 int 625 badaddr_read(void *addr, size_t size, int *rptr) 626 { 627 struct faultbuf env; 628 int x; 629 630 /* Get rid of any stale machine checks that have been waiting. */ 631 __asm volatile ("sync; isync"); 632 633 if (setfault(&env)) { 634 curpcb->pcb_onfault = NULL; 635 __asm volatile ("sync"); 636 return 1; 637 } 638 639 __asm volatile ("sync"); 640 641 switch (size) { 642 case 1: 643 x = *(volatile int8_t *)addr; 644 break; 645 case 2: 646 x = *(volatile int16_t *)addr; 647 break; 648 case 4: 649 x = *(volatile int32_t *)addr; 650 break; 651 default: 652 panic("badaddr: invalid size (%d)", size); 653 } 654 655 /* Make sure we took the machine check, if we caused one. */ 656 __asm volatile ("sync; isync"); 657 658 curpcb->pcb_onfault = NULL; 659 __asm volatile ("sync"); /* To be sure. */ 660 661 /* Use the value to avoid reorder. */ 662 if (rptr) 663 *rptr = x; 664 665 return 0; 666 } 667 668 /* 669 * For now, this only deals with the particular unaligned access case 670 * that gcc tends to generate. Eventually it should handle all of the 671 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 672 */ 673 674 static int 675 fix_unaligned(struct lwp *l, struct trapframe *tf) 676 { 677 678 return -1; 679 } 680
Indexes created Tue Sep 30 20:09:53 GMT 2025