trap.c revision 1.19
1 /* $NetBSD: trap.c,v 1.19 2003/10/08 00:28:42 thorpej 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 1.19 2003/10/08 00:28:42 thorpej Exp $"); 71 72 #include "opt_altivec.h" 73 #include "opt_ddb.h" 74 #include "opt_ktrace.h" 75 #include "opt_systrace.h" 76 #include "opt_syscall_debug.h" 77 78 #include <sys/param.h> 79 #include <sys/proc.h> 80 #include <sys/reboot.h> 81 #include <sys/syscall.h> 82 #include <sys/systm.h> 83 #include <sys/user.h> 84 #ifdef KTRACE 85 #include <sys/ktrace.h> 86 #endif 87 #include <sys/pool.h> 88 #include <sys/sa.h> 89 #include <sys/savar.h> 90 #ifdef SYSTRACE 91 #include <sys/systrace.h> 92 #endif 93 94 #include <uvm/uvm_extern.h> 95 96 #include <dev/cons.h> 97 98 #include <machine/cpu.h> 99 #include <machine/db_machdep.h> 100 #include <machine/fpu.h> 101 #include <machine/frame.h> 102 #include <machine/pcb.h> 103 #include <machine/psl.h> 104 #include <machine/trap.h> 105 106 #include <powerpc/spr.h> 107 #include <powerpc/ibm4xx/pmap.h> 108 #include <powerpc/ibm4xx/tlb.h> 109 #include <powerpc/fpu/fpu_extern.h> 110 111 /* These definitions should probably be somewhere else XXX */ 112 #define FIRSTARG 3 /* first argument is in reg 3 */ 113 #define NARGREG 8 /* 8 args are in registers */ 114 #define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */ 115 116 static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); 117 118 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 119 /* Why are these not defined in a header? */ 120 int badaddr __P((void *, size_t)); 121 int badaddr_read __P((void *, size_t, int *)); 122 int ctx_setup __P((int, int)); 123 124 #ifdef DEBUG 125 #define TDB_ALL 0x1 126 int trapdebug = /* TDB_ALL */ 0; 127 #define DBPRINTF(x, y) if (trapdebug & (x)) printf y 128 #else 129 #define DBPRINTF(x, y) 130 #endif 131 132 void 133 trap(struct trapframe *frame) 134 { 135 struct lwp *l = curlwp; 136 struct proc *p = l ? l->l_proc : NULL; 137 int type = frame->exc; 138 int ftype, rv; 139 ksiginfo_t ksi; 140 141 KASSERT(l == 0 || (l->l_stat == LSONPROC)); 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 %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 KERNEL_PROC_LOCK(l); 172 trapsignal(l, &ksi); 173 KERNEL_PROC_UNLOCK(l); 174 break; 175 176 /* 177 * If we could not find and install appropriate TLB entry, fall through. 178 */ 179 180 case EXC_DSI: 181 /* FALLTHROUGH */ 182 case EXC_DTMISS: 183 { 184 struct vm_map *map; 185 vaddr_t va; 186 struct faultbuf *fb = NULL; 187 188 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE); 189 va = frame->dar; 190 if (frame->tf_xtra[TF_PID] == KERNEL_PID) { 191 map = kernel_map; 192 } else { 193 map = &p->p_vmspace->vm_map; 194 if (l->l_flag & L_SA) { 195 KDASSERT(p != NULL && p->p_sa != NULL); 196 p->p_sa->sa_vp_faultaddr = va; 197 l->l_flag |= L_SA_PAGEFAULT; 198 } 199 } 200 201 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 202 ftype = VM_PROT_WRITE; 203 204 DBPRINTF(TDB_ALL, 205 ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", 206 frame->srr0, 207 (ftype & VM_PROT_WRITE) ? "write" : "read", 208 (void *)va, frame->tf_xtra[TF_ESR])); 209 rv = uvm_fault(map, trunc_page(va), 0, ftype); 210 KERNEL_UNLOCK(); 211 if (map != kernel_map) 212 l->l_flag &= ~L_SA_PAGEFAULT; 213 if (rv == 0) 214 goto done; 215 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 216 frame->tf_xtra[TF_PID] = KERNEL_PID; 217 frame->srr0 = fb->fb_pc; 218 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 219 frame->fixreg[1] = fb->fb_sp; 220 frame->fixreg[2] = fb->fb_r2; 221 frame->fixreg[3] = 1; /* Return TRUE */ 222 frame->cr = fb->fb_cr; 223 memcpy(&frame->fixreg[13], fb->fb_fixreg, 224 sizeof(fb->fb_fixreg)); 225 goto done; 226 } 227 } 228 goto brain_damage; 229 230 case EXC_DSI|EXC_USER: 231 /* FALLTHROUGH */ 232 case EXC_DTMISS|EXC_USER: 233 KERNEL_PROC_LOCK(l); 234 235 if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) 236 ftype = VM_PROT_WRITE; 237 238 DBPRINTF(TDB_ALL, 239 ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", 240 frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", 241 frame->dar, frame->tf_xtra[TF_ESR])); 242 KASSERT(l == curlwp && (l->l_stat == LSONPROC)); 243 if (l->l_flag & L_SA) { 244 KDASSERT(p != NULL && p->p_sa != NULL); 245 p->p_sa->sa_vp_faultaddr = (vaddr_t)frame->dar; 246 l->l_flag |= L_SA_PAGEFAULT; 247 } 248 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 249 0, ftype); 250 if (rv == 0) { 251 l->l_flag &= ~L_SA_PAGEFAULT; 252 KERNEL_PROC_UNLOCK(l); 253 break; 254 } 255 KSI_INIT_TRAP(&ksi); 256 ksi.ksi_signo = SIGSEGV; 257 ksi.ksi_trap = EXC_DSI; 258 ksi.ksi_addr = (void *)frame->dar; 259 if (rv == ENOMEM) { 260 printf("UVM: pid %d (%s) lid %d, uid %d killed: " 261 "out of swap\n", 262 p->p_pid, p->p_comm, l->l_lid, 263 p->p_cred && p->p_ucred ? 264 p->p_ucred->cr_uid : -1); 265 ksi.ksi_signo = SIGKILL; 266 } 267 trapsignal(l, &ksi); 268 l->l_flag &= ~L_SA_PAGEFAULT; 269 KERNEL_PROC_UNLOCK(l); 270 break; 271 272 case EXC_ITMISS|EXC_USER: 273 case EXC_ISI|EXC_USER: 274 KERNEL_PROC_LOCK(l); 275 if (l->l_flag & L_SA) { 276 KDASSERT(p != NULL && p->p_sa != NULL); 277 p->p_sa->sa_vp_faultaddr = (vaddr_t)frame->srr0; 278 l->l_flag |= L_SA_PAGEFAULT; 279 } 280 ftype = VM_PROT_EXECUTE; 281 DBPRINTF(TDB_ALL, 282 ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", 283 frame->srr0, frame)); 284 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 285 0, ftype); 286 if (rv == 0) { 287 l->l_flag &= ~L_SA_PAGEFAULT; 288 KERNEL_PROC_UNLOCK(l); 289 break; 290 } 291 KSI_INIT_TRAP(&ksi); 292 ksi.ksi_signo = SIGSEGV; 293 ksi.ksi_trap = EXC_ISI; 294 ksi.ksi_addr = (void *)frame->srr0; 295 trapsignal(l, &ksi); 296 l->l_flag &= ~L_SA_PAGEFAULT; 297 KERNEL_PROC_UNLOCK(l); 298 break; 299 300 case EXC_AST|EXC_USER: 301 curcpu()->ci_astpending = 0; /* we are about to do it */ 302 KERNEL_PROC_LOCK(l); 303 uvmexp.softs++; 304 if (p->p_flag & P_OWEUPC) { 305 p->p_flag &= ~P_OWEUPC; 306 ADDUPROF(p); 307 } 308 /* Check whether we are being preempted. */ 309 if (curcpu()->ci_want_resched) 310 preempt(0); 311 KERNEL_PROC_UNLOCK(l); 312 break; 313 314 315 case EXC_ALI|EXC_USER: 316 KERNEL_PROC_LOCK(l); 317 if (fix_unaligned(l, frame) != 0) { 318 KSI_INIT_TRAP(&ksi); 319 ksi.ksi_signo = SIGBUS; 320 ksi.ksi_trap = EXC_ALI; 321 ksi.ksi_addr = (void *)frame->dar; 322 trapsignal(l, &ksi); 323 } else 324 frame->srr0 += 4; 325 KERNEL_PROC_UNLOCK(l); 326 break; 327 328 case EXC_PGM|EXC_USER: 329 /* 330 * Illegal insn: 331 * 332 * let's try to see if it's FPU and can be emulated. 333 */ 334 uvmexp.traps ++; 335 if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { 336 memset(&l->l_addr->u_pcb.pcb_fpu, 0, 337 sizeof l->l_addr->u_pcb.pcb_fpu); 338 l->l_addr->u_pcb.pcb_flags |= PCB_FPU; 339 } 340 341 if ((rv = fpu_emulate(frame, 342 (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { 343 KSI_INIT_TRAP(&ksi); 344 ksi.ksi_signo = rv; 345 ksi.ksi_trap = EXC_PGM; 346 ksi.ksi_addr = (void *)frame->srr0; 347 KERNEL_PROC_LOCK(l); 348 trapsignal(l, &ksi); 349 KERNEL_PROC_UNLOCK(l); 350 } 351 break; 352 353 case EXC_MCHK: 354 { 355 struct faultbuf *fb; 356 357 if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { 358 frame->tf_xtra[TF_PID] = KERNEL_PID; 359 frame->srr0 = fb->fb_pc; 360 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 361 frame->fixreg[1] = fb->fb_sp; 362 frame->fixreg[2] = fb->fb_r2; 363 frame->fixreg[3] = 1; /* Return TRUE */ 364 frame->cr = fb->fb_cr; 365 memcpy(&frame->fixreg[13], fb->fb_fixreg, 366 sizeof(fb->fb_fixreg)); 367 goto done; 368 } 369 } 370 goto brain_damage; 371 default: 372 brain_damage: 373 printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); 374 #ifdef DDB 375 if (kdb_trap(type, frame)) 376 goto done; 377 #endif 378 #ifdef TRAP_PANICWAIT 379 printf("Press a key to panic.\n"); 380 cngetc(); 381 #endif 382 panic("trap"); 383 } 384 385 /* Take pending signals. */ 386 { 387 int sig; 388 389 while ((sig = CURSIG(l)) != 0) 390 postsig(sig); 391 } 392 393 /* Invoke per-process kernel-exit handling, if any */ 394 if (p->p_userret) 395 (p->p_userret)(l, p->p_userret_arg); 396 397 /* Invoke any pending upcalls */ 398 while (l->l_flag & L_SA_UPCALL) 399 sa_upcall_userret(l); 400 401 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 402 done: 403 return; 404 } 405 406 int 407 ctx_setup(int ctx, int srr1) 408 { 409 volatile struct pmap *pm; 410 411 /* Update PID if we're returning to user mode. */ 412 if (srr1 & PSL_PR) { 413 pm = curproc->p_vmspace->vm_map.pmap; 414 if (!pm->pm_ctx) { 415 ctx_alloc((struct pmap *)pm); 416 } 417 ctx = pm->pm_ctx; 418 if (srr1 & PSL_SE) { 419 int dbreg, mask = 0x48000000; 420 /* 421 * Set the Internal Debug and 422 * Instruction Completion bits of 423 * the DBCR0 register. 424 * 425 * XXX this is also used by jtag debuggers... 426 */ 427 __asm __volatile("mfspr %0,0x3f2;" 428 "or %0,%0,%1;" 429 "mtspr 0x3f2,%0;" : 430 "=&r" (dbreg) : "r" (mask)); 431 } 432 } 433 else if (!ctx) { 434 ctx = KERNEL_PID; 435 } 436 return (ctx); 437 } 438 439 /* 440 * Used by copyin()/copyout() 441 */ 442 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 443 extern void vunmaprange __P((vaddr_t, vsize_t)); 444 static int bigcopyin __P((const void *, void *, size_t )); 445 static int bigcopyout __P((const void *, void *, size_t )); 446 447 int 448 copyin(const void *udaddr, void *kaddr, size_t len) 449 { 450 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 451 int msr, pid, tmp, ctx; 452 struct faultbuf env; 453 454 /* For bigger buffers use the faster copy */ 455 if (len > 256) return (bigcopyin(udaddr, kaddr, len)); 456 457 if (setfault(&env)) { 458 curpcb->pcb_onfault = 0; 459 return EFAULT; 460 } 461 462 if (!(ctx = pm->pm_ctx)) { 463 /* No context -- assign it one */ 464 ctx_alloc(pm); 465 ctx = pm->pm_ctx; 466 } 467 468 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 469 "mfmsr %0;" /* Save MSR */ 470 "li %1,0x20; " 471 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 472 "mfpid %1;" /* Save old PID */ 473 "sync; isync;" 474 475 "1: bdz 2f;" /* while len */ 476 "mtpid %3; sync;" /* Load user ctx */ 477 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 478 "sync; isync;" 479 "mtpid %1;sync;" 480 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 481 "sync; isync;" 482 "b 1b;" /* repeat */ 483 484 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 485 "sync; isync;" 486 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 487 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 488 489 curpcb->pcb_onfault = 0; 490 return 0; 491 } 492 493 static int 494 bigcopyin(const void *udaddr, void *kaddr, size_t len) 495 { 496 const char *up; 497 char *kp = kaddr; 498 struct lwp *l = curlwp; 499 struct proc *p; 500 int error; 501 502 if (!l) { 503 return EFAULT; 504 } 505 506 p = l->l_proc; 507 508 /* 509 * Stolen from physio(): 510 */ 511 PHOLD(l); 512 error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ); 513 if (error) { 514 PRELE(l); 515 return EFAULT; 516 } 517 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 518 519 memcpy(kp, up, len); 520 vunmaprange((vaddr_t)up, len); 521 uvm_vsunlock(p, (caddr_t)udaddr, len); 522 PRELE(l); 523 524 return 0; 525 } 526 527 int 528 copyout(const void *kaddr, void *udaddr, size_t len) 529 { 530 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 531 int msr, pid, tmp, ctx; 532 struct faultbuf env; 533 534 /* For big copies use more efficient routine */ 535 if (len > 256) return (bigcopyout(kaddr, udaddr, len)); 536 537 if (setfault(&env)) { 538 curpcb->pcb_onfault = 0; 539 return EFAULT; 540 } 541 542 if (!(ctx = pm->pm_ctx)) { 543 /* No context -- assign it one */ 544 ctx_alloc(pm); 545 ctx = pm->pm_ctx; 546 } 547 548 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 549 "mfmsr %0;" /* Save MSR */ 550 "li %1,0x20; " 551 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 552 "mfpid %1;" /* Save old PID */ 553 "sync; isync;" 554 555 "1: bdz 2f;" /* while len */ 556 "mtpid %1;sync;" 557 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 558 "sync; isync;" 559 "mtpid %3; sync;" /* Load user ctx */ 560 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 561 "sync; isync;" 562 "b 1b;" /* repeat */ 563 564 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 565 "sync; isync;" 566 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 567 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 568 569 curpcb->pcb_onfault = 0; 570 return 0; 571 } 572 573 static int 574 bigcopyout(const void *kaddr, void *udaddr, size_t len) 575 { 576 char *up; 577 const char *kp = (char *)kaddr; 578 struct lwp *l = curlwp; 579 struct proc *p; 580 int error; 581 582 if (!l) { 583 return EFAULT; 584 } 585 586 p = l->l_proc; 587 588 /* 589 * Stolen from physio(): 590 */ 591 PHOLD(l); 592 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); 593 if (error) { 594 PRELE(l); 595 return EFAULT; 596 } 597 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 598 VM_PROT_READ | VM_PROT_WRITE); 599 600 memcpy(up, kp, len); 601 vunmaprange((vaddr_t)up, len); 602 uvm_vsunlock(p, udaddr, len); 603 PRELE(l); 604 605 return 0; 606 } 607 608 /* 609 * kcopy(const void *src, void *dst, size_t len); 610 * 611 * Copy len bytes from src to dst, aborting if we encounter a fatal 612 * page fault. 613 * 614 * kcopy() _must_ save and restore the old fault handler since it is 615 * called by uiomove(), which may be in the path of servicing a non-fatal 616 * page fault. 617 */ 618 int 619 kcopy(const void *src, void *dst, size_t len) 620 { 621 struct faultbuf env, *oldfault; 622 623 oldfault = curpcb->pcb_onfault; 624 if (setfault(&env)) { 625 curpcb->pcb_onfault = oldfault; 626 return EFAULT; 627 } 628 629 memcpy(dst, src, len); 630 631 curpcb->pcb_onfault = oldfault; 632 return 0; 633 } 634 635 int 636 badaddr(void *addr, size_t size) 637 { 638 639 return badaddr_read(addr, size, NULL); 640 } 641 642 int 643 badaddr_read(void *addr, size_t size, int *rptr) 644 { 645 struct faultbuf env; 646 int x; 647 648 /* Get rid of any stale machine checks that have been waiting. */ 649 __asm __volatile ("sync; isync"); 650 651 if (setfault(&env)) { 652 curpcb->pcb_onfault = 0; 653 __asm __volatile ("sync"); 654 return 1; 655 } 656 657 __asm __volatile ("sync"); 658 659 switch (size) { 660 case 1: 661 x = *(volatile int8_t *)addr; 662 break; 663 case 2: 664 x = *(volatile int16_t *)addr; 665 break; 666 case 4: 667 x = *(volatile int32_t *)addr; 668 break; 669 default: 670 panic("badaddr: invalid size (%d)", size); 671 } 672 673 /* Make sure we took the machine check, if we caused one. */ 674 __asm __volatile ("sync; isync"); 675 676 curpcb->pcb_onfault = 0; 677 __asm __volatile ("sync"); /* To be sure. */ 678 679 /* Use the value to avoid reorder. */ 680 if (rptr) 681 *rptr = x; 682 683 return 0; 684 } 685 686 /* 687 * For now, this only deals with the particular unaligned access case 688 * that gcc tends to generate. Eventually it should handle all of the 689 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 690 */ 691 692 static int 693 fix_unaligned(struct lwp *l, struct trapframe *frame) 694 { 695 696 return -1; 697 } 698 699 /* 700 * Start a new LWP 701 */ 702 void 703 startlwp(arg) 704 void *arg; 705 { 706 int err; 707 ucontext_t *uc = arg; 708 struct lwp *l = curlwp; 709 710 err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); 711 #if DIAGNOSTIC 712 if (err) { 713 printf("Error %d from cpu_setmcontext.", err); 714 } 715 #endif 716 pool_put(&lwp_uc_pool, uc); 717 718 upcallret(l); 719 } 720 721 /* 722 * XXX This is a terrible name. 723 */ 724 void 725 upcallret(l) 726 struct lwp *l; 727 { 728 int sig; 729 730 /* Take pending signals. */ 731 while ((sig = CURSIG(l)) != 0) 732 postsig(sig); 733 734 /* Invoke per-process kernel-exit handling, if any */ 735 if (l->l_proc->p_userret) 736 (l->l_proc->p_userret)(l, l->l_proc->p_userret_arg); 737 738 /* Invoke any pending upcalls */ 739 while (l->l_flag & L_SA_UPCALL) 740 sa_upcall_userret(l); 741 742 curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; 743 } 744
Indexes created Mon Sep 22 13:09:51 GMT 2025