trap.c revision 1.3.8.2
1 /* $NetBSD: trap.c,v 1.3.8.2 2002/07/16 13:09:57 gehenna 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 "opt_altivec.h" 70 #include "opt_ddb.h" 71 #include "opt_ktrace.h" 72 #include "opt_systrace.h" 73 #include "opt_syscall_debug.h" 74 75 #include <sys/param.h> 76 #include <sys/proc.h> 77 #include <sys/reboot.h> 78 #include <sys/syscall.h> 79 #include <sys/systm.h> 80 #include <sys/user.h> 81 #ifdef KTRACE 82 #include <sys/ktrace.h> 83 #endif 84 #ifdef SYSTRACE 85 #include <sys/systrace.h> 86 #endif 87 88 #include <uvm/uvm_extern.h> 89 90 #include <dev/cons.h> 91 92 #include <machine/cpu.h> 93 #include <machine/db_machdep.h> 94 #include <machine/fpu.h> 95 #include <machine/frame.h> 96 #include <machine/pcb.h> 97 #include <machine/psl.h> 98 #include <machine/trap.h> 99 100 #include <powerpc/spr.h> 101 #include <powerpc/ibm4xx/pmap.h> 102 #include <powerpc/ibm4xx/tlb.h> 103 #include <powerpc/fpu/fpu_extern.h> 104 105 /* These definitions should probably be somewhere else XXX */ 106 #define FIRSTARG 3 /* first argument is in reg 3 */ 107 #define NARGREG 8 /* 8 args are in registers */ 108 #define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */ 109 110 #ifndef MULTIPROCESSOR 111 volatile int astpending; 112 volatile int want_resched; 113 #endif 114 115 static int fix_unaligned __P((struct proc *p, struct trapframe *frame)); 116 117 void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ 118 int setfault __P((faultbuf)); /* defined in locore.S */ 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 proc *p = curproc; 136 int type = frame->exc; 137 int ftype, rv; 138 139 KASSERT(p == 0 || (p->p_stat == SONPROC)); 140 141 if (frame->srr1 & PSL_PR) 142 type |= EXC_USER; 143 144 ftype = VM_PROT_READ; 145 146 DBPRINTF(TDB_ALL, ("trap(%x) at %x 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 __asm __volatile("mfspr %0,0x3f0" : "=r" (rv), "=r" (srr2), "=r" (srr3) :); 154 printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, srr3); 155 } 156 /* 157 * DEBUG intr -- probably single-step. 158 */ 159 case EXC_TRC|EXC_USER: 160 KERNEL_PROC_LOCK(p); 161 frame->srr1 &= ~PSL_SE; 162 trapsignal(p, SIGTRAP, EXC_TRC); 163 KERNEL_PROC_UNLOCK(p); 164 break; 165 166 /* If we could not find and install appropriate TLB entry, fall through */ 167 168 case EXC_DSI: 169 /* FALLTHROUGH */ 170 case EXC_DTMISS: 171 { 172 struct vm_map *map; 173 vaddr_t va; 174 faultbuf *fb = NULL; 175 176 KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE); 177 va = frame->dear; 178 if (frame->pid == KERNEL_PID) { 179 map = kernel_map; 180 } else { 181 map = &p->p_vmspace->vm_map; 182 } 183 184 if (frame->esr & (ESR_DST|ESR_DIZ)) 185 ftype = VM_PROT_WRITE; 186 187 DBPRINTF(TDB_ALL, ("trap(EXC_DSI) at %x %s fault on %p esr %x\n", 188 frame->srr0, (ftype&VM_PROT_WRITE) ? "write" : "read", (void *)va, frame->esr)); 189 rv = uvm_fault(map, trunc_page(va), 0, ftype); 190 KERNEL_UNLOCK(); 191 if (rv == 0) 192 goto done; 193 if ((fb = p->p_addr->u_pcb.pcb_onfault) != NULL) { 194 frame->pid = KERNEL_PID; 195 frame->srr0 = (*fb)[0]; 196 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 197 frame->fixreg[1] = (*fb)[1]; 198 frame->fixreg[2] = (*fb)[2]; 199 frame->fixreg[3] = 1; /* Return TRUE */ 200 frame->cr = (*fb)[3]; 201 memcpy(&frame->fixreg[13], &(*fb)[4], 202 19 * sizeof(register_t)); 203 goto done; 204 } 205 } 206 goto brain_damage; 207 208 case EXC_DSI|EXC_USER: 209 /* FALLTHROUGH */ 210 case EXC_DTMISS|EXC_USER: 211 KERNEL_PROC_LOCK(p); 212 213 if (frame->esr & (ESR_DST|ESR_DIZ)) 214 ftype = VM_PROT_WRITE; 215 216 DBPRINTF(TDB_ALL, ("trap(EXC_DSI|EXC_USER) at %x %s fault on %x %x\n", 217 frame->srr0, (ftype&VM_PROT_WRITE) ? "write" : "read", frame->dear, frame->esr)); 218 KASSERT(p == curproc && (p->p_stat == SONPROC)); 219 rv = uvm_fault(&p->p_vmspace->vm_map, 220 trunc_page(frame->dear), 0, ftype); 221 if (rv == 0) { 222 KERNEL_PROC_UNLOCK(p); 223 break; 224 } 225 if (rv == ENOMEM) { 226 printf("UVM: pid %d (%s), uid %d killed: " 227 "out of swap\n", 228 p->p_pid, p->p_comm, 229 p->p_cred && p->p_ucred ? 230 p->p_ucred->cr_uid : -1); 231 trapsignal(p, SIGKILL, EXC_DSI); 232 } else { 233 trapsignal(p, SIGSEGV, EXC_DSI); 234 } 235 KERNEL_PROC_UNLOCK(p); 236 break; 237 case EXC_ITMISS|EXC_USER: 238 case EXC_ISI|EXC_USER: 239 KERNEL_PROC_LOCK(p); 240 ftype = VM_PROT_READ | VM_PROT_EXECUTE; 241 DBPRINTF(TDB_ALL, ("trap(EXC_ISI|EXC_USER) at %x %s fault on %x tf %p\n", 242 frame->srr0, (ftype&VM_PROT_WRITE) ? "write" : "read", frame->srr0, frame)); 243 rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 0, ftype); 244 if (rv == 0) { 245 KERNEL_PROC_UNLOCK(p); 246 break; 247 } 248 trapsignal(p, SIGSEGV, EXC_ISI); 249 KERNEL_PROC_UNLOCK(p); 250 break; 251 252 case EXC_SC|EXC_USER: 253 (*p->p_md.md_syscall)(frame); 254 break; 255 256 case EXC_AST|EXC_USER: 257 astpending = 0; /* we are about to do it */ 258 KERNEL_PROC_LOCK(p); 259 uvmexp.softs++; 260 if (p->p_flag & P_OWEUPC) { 261 p->p_flag &= ~P_OWEUPC; 262 ADDUPROF(p); 263 } 264 /* Check whether we are being preempted. */ 265 if (want_resched) 266 preempt(NULL); 267 KERNEL_PROC_UNLOCK(p); 268 break; 269 270 271 case EXC_ALI|EXC_USER: 272 KERNEL_PROC_LOCK(p); 273 if (fix_unaligned(p, frame) != 0) 274 trapsignal(p, SIGBUS, EXC_ALI); 275 else 276 frame->srr0 += 4; 277 KERNEL_PROC_UNLOCK(p); 278 break; 279 280 case EXC_PGM|EXC_USER: 281 /* 282 * Illegal insn: 283 * 284 * let's try to see if it's FPU and can be emulated. 285 */ 286 uvmexp.traps ++; 287 if (!(p->p_addr->u_pcb.pcb_flags & PCB_FPU)) { 288 memset(&p->p_addr->u_pcb.pcb_fpu, 0, 289 sizeof p->p_addr->u_pcb.pcb_fpu); 290 p->p_addr->u_pcb.pcb_flags |= PCB_FPU; 291 } 292 293 if ((rv = fpu_emulate(frame, 294 (struct fpreg *)&p->p_addr->u_pcb.pcb_fpu))) { 295 KERNEL_PROC_LOCK(p); 296 trapsignal(p, rv, EXC_PGM); 297 KERNEL_PROC_UNLOCK(p); 298 } 299 break; 300 301 case EXC_MCHK: 302 { 303 faultbuf *fb; 304 305 if ((fb = p->p_addr->u_pcb.pcb_onfault) != NULL) { 306 frame->pid = KERNEL_PID; 307 frame->srr0 = (*fb)[0]; 308 frame->srr1 |= PSL_IR; /* Re-enable IMMU */ 309 frame->fixreg[1] = (*fb)[1]; 310 frame->fixreg[2] = (*fb)[2]; 311 frame->fixreg[3] = 1; /* Return TRUE */ 312 frame->cr = (*fb)[3]; 313 memcpy(&frame->fixreg[13], &(*fb)[4], 314 19 * sizeof(register_t)); 315 goto done; 316 } 317 } 318 goto brain_damage; 319 default: 320 brain_damage: 321 printf("trap type 0x%x at 0x%x\n", type, frame->srr0); 322 #ifdef DDB 323 if (kdb_trap(type, frame)) 324 goto done; 325 #endif 326 #ifdef TRAP_PANICWAIT 327 printf("Press a key to panic.\n"); 328 cngetc(); 329 #endif 330 panic("trap"); 331 } 332 333 /* Take pending signals. */ 334 { 335 int sig; 336 337 while ((sig = CURSIG(p)) != 0) 338 postsig(sig); 339 } 340 341 curcpu()->ci_schedstate.spc_curpriority = p->p_priority = p->p_usrpri; 342 done: 343 } 344 345 int 346 ctx_setup(int ctx, int srr1) 347 { 348 volatile struct pmap *pm; 349 350 /* Update PID if we're returning to user mode. */ 351 if (srr1 & PSL_PR) { 352 pm = curproc->p_vmspace->vm_map.pmap; 353 if (!pm->pm_ctx) { 354 ctx_alloc((struct pmap *)pm); 355 } 356 ctx = pm->pm_ctx; 357 if (srr1 & PSL_SE) { 358 int dbreg, mask = 0x48000000; 359 /* 360 * Set the Internal Debug and 361 * Instruction Completion bits of 362 * the DBCR0 register. 363 * 364 * XXX this is also used by jtag debuggers... 365 */ 366 __asm __volatile("mfspr %0,0x3f2;" 367 "or %0,%0,%1;" 368 "mtspr 0x3f2,%0;" : 369 "=&r" (dbreg) : "r" (mask)); 370 } 371 } 372 else if (!ctx) { 373 ctx = KERNEL_PID; 374 } 375 return (ctx); 376 } 377 378 /* 379 * Used by copyin()/copyout() 380 */ 381 extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); 382 extern void vunmaprange __P((vaddr_t, vsize_t)); 383 static int bigcopyin __P((const void *, void *, size_t )); 384 static int bigcopyout __P((const void *, void *, size_t )); 385 386 int 387 copyin(const void *udaddr, void *kaddr, size_t len) 388 { 389 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 390 int msr, pid, tmp, ctx; 391 faultbuf env; 392 393 /* For bigger buffers use the faster copy */ 394 if (len > 256) return (bigcopyin(udaddr, kaddr, len)); 395 396 if (setfault(env)) { 397 curpcb->pcb_onfault = 0; 398 return EFAULT; 399 } 400 401 if (!(ctx = pm->pm_ctx)) { 402 /* No context -- assign it one */ 403 ctx_alloc(pm); 404 ctx = pm->pm_ctx; 405 } 406 407 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 408 "mfmsr %0;" /* Save MSR */ 409 "li %1,0x20; " 410 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 411 "mfpid %1;" /* Save old PID */ 412 "sync; isync;" 413 414 "1: bdz 2f;" /* while len */ 415 "mtpid %3; sync;" /* Load user ctx */ 416 "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ 417 "sync; isync;" 418 "mtpid %1;sync;" 419 "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ 420 "sync; isync;" 421 "b 1b;" /* repeat */ 422 423 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 424 "sync; isync;" 425 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 426 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 427 428 curpcb->pcb_onfault = 0; 429 return 0; 430 } 431 432 static int 433 bigcopyin(const void *udaddr, void *kaddr, size_t len) 434 { 435 const char *up; 436 char *kp = kaddr; 437 struct proc *p = curproc; 438 int error; 439 440 if (!p) { 441 return EFAULT; 442 } 443 444 /* 445 * Stolen from physio(): 446 */ 447 PHOLD(p); 448 error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ); 449 if (error) { 450 PRELE(p); 451 return EFAULT; 452 } 453 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); 454 455 memcpy(kp, up, len); 456 vunmaprange((vaddr_t)up, len); 457 uvm_vsunlock(p, (caddr_t)udaddr, len); 458 PRELE(p); 459 460 return 0; 461 } 462 463 int 464 copyout(const void *kaddr, void *udaddr, size_t len) 465 { 466 struct pmap *pm = curproc->p_vmspace->vm_map.pmap; 467 int msr, pid, tmp, ctx; 468 faultbuf env; 469 470 /* For big copies use more efficient routine */ 471 if (len > 256) return (bigcopyout(kaddr, udaddr, len)); 472 473 if (setfault(env)) { 474 curpcb->pcb_onfault = 0; 475 return EFAULT; 476 } 477 478 if (!(ctx = pm->pm_ctx)) { 479 /* No context -- assign it one */ 480 ctx_alloc(pm); 481 ctx = pm->pm_ctx; 482 } 483 484 asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ 485 "mfmsr %0;" /* Save MSR */ 486 "li %1,0x20; " 487 "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ 488 "mfpid %1;" /* Save old PID */ 489 "sync; isync;" 490 491 "1: bdz 2f;" /* while len */ 492 "mtpid %1;sync;" 493 "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ 494 "sync; isync;" 495 "mtpid %3; sync;" /* Load user ctx */ 496 "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ 497 "sync; isync;" 498 "b 1b;" /* repeat */ 499 500 "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ 501 "sync; isync;" 502 : "=&r" (msr), "=&r" (pid), "=&r" (tmp) 503 : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); 504 505 curpcb->pcb_onfault = 0; 506 return 0; 507 } 508 509 static int 510 bigcopyout(const void *kaddr, void *udaddr, size_t len) 511 { 512 char *up; 513 const char *kp = (char *)kaddr; 514 struct proc *p = curproc; 515 int error; 516 517 if (!p) { 518 return EFAULT; 519 } 520 521 /* 522 * Stolen from physio(): 523 */ 524 PHOLD(p); 525 error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); 526 if (error) { 527 PRELE(p); 528 return EFAULT; 529 } 530 up = (char *)vmaprange(p, (vaddr_t)udaddr, len, 531 VM_PROT_READ|VM_PROT_WRITE); 532 533 memcpy(up, kp, len); 534 vunmaprange((vaddr_t)up, len); 535 uvm_vsunlock(p, udaddr, len); 536 PRELE(p); 537 538 return 0; 539 } 540 541 /* 542 * kcopy(const void *src, void *dst, size_t len); 543 * 544 * Copy len bytes from src to dst, aborting if we encounter a fatal 545 * page fault. 546 * 547 * kcopy() _must_ save and restore the old fault handler since it is 548 * called by uiomove(), which may be in the path of servicing a non-fatal 549 * page fault. 550 */ 551 int 552 kcopy(const void *src, void *dst, size_t len) 553 { 554 faultbuf env, *oldfault; 555 556 oldfault = curpcb->pcb_onfault; 557 if (setfault(env)) { 558 curpcb->pcb_onfault = oldfault; 559 return EFAULT; 560 } 561 562 memcpy(dst, src, len); 563 564 curpcb->pcb_onfault = oldfault; 565 return 0; 566 } 567 568 int 569 badaddr(void *addr, size_t size) 570 { 571 572 return badaddr_read(addr, size, NULL); 573 } 574 575 int 576 badaddr_read(void *addr, size_t size, int *rptr) 577 { 578 faultbuf env; 579 int x; 580 581 /* Get rid of any stale machine checks that have been waiting. */ 582 __asm __volatile ("sync; isync"); 583 584 if (setfault(env)) { 585 curpcb->pcb_onfault = 0; 586 __asm __volatile ("sync"); 587 return 1; 588 } 589 590 __asm __volatile ("sync"); 591 592 switch (size) { 593 case 1: 594 x = *(volatile int8_t *)addr; 595 break; 596 case 2: 597 x = *(volatile int16_t *)addr; 598 break; 599 case 4: 600 x = *(volatile int32_t *)addr; 601 break; 602 default: 603 panic("badaddr: invalid size (%d)", size); 604 } 605 606 /* Make sure we took the machine check, if we caused one. */ 607 __asm __volatile ("sync; isync"); 608 609 curpcb->pcb_onfault = 0; 610 __asm __volatile ("sync"); /* To be sure. */ 611 612 /* Use the value to avoid reorder. */ 613 if (rptr) 614 *rptr = x; 615 616 return 0; 617 } 618 619 /* 620 * For now, this only deals with the particular unaligned access case 621 * that gcc tends to generate. Eventually it should handle all of the 622 * possibilities that can happen on a 32-bit PowerPC in big-endian mode. 623 */ 624 625 static int 626 fix_unaligned(struct proc *p, struct trapframe *frame) 627 { 628 629 return -1; 630 } 631
Indexes created Tue Sep 30 20:09:53 GMT 2025