1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <sys/dtrace_impl.h> 30 #include <sys/stack.h> 31 #include <sys/frame.h> 32 #include <sys/cmn_err.h> 33 #include <sys/privregs.h> 34 #include <sys/sysmacros.h> 35 36 extern uintptr_t kernelbase; 37 38 void 39 dtrace_getpcstack(pc_t *pcstack, int pcstack_limit, int aframes, 40 uint32_t *intrpc) 41 { 42 struct frame *fp = (struct frame *)dtrace_getfp(); 43 struct frame *nextfp, *minfp, *stacktop; 44 int depth = 0; 45 int on_intr, last = 0; 46 uintptr_t pc; 47 uintptr_t caller = CPU->cpu_dtrace_caller; 48 49 if ((on_intr = CPU_ON_INTR(CPU)) != 0) 50 stacktop = (struct frame *)(CPU->cpu_intr_stack + SA(MINFRAME)); 51 else 52 stacktop = (struct frame *)curthread->t_stk; 53 minfp = fp; 54 55 aframes++; 56 57 if (intrpc != NULL && depth < pcstack_limit) 58 pcstack[depth++] = (pc_t)intrpc; 59 60 while (depth < pcstack_limit) { 61 nextfp = (struct frame *)fp->fr_savfp; 62 pc = fp->fr_savpc; 63 64 if (nextfp <= minfp || nextfp >= stacktop) { 65 if (on_intr) { 66 /* 67 * Hop from interrupt stack to thread stack. 68 */ 69 stacktop = (struct frame *)curthread->t_stk; 70 minfp = (struct frame *)curthread->t_stkbase; 71 on_intr = 0; 72 continue; 73 } 74 75 /* 76 * This is the last frame we can process; indicate 77 * that we should return after processing this frame. 78 */ 79 last = 1; 80 } 81 82 if (aframes > 0) { 83 if (--aframes == 0 && caller != NULL) { 84 /* 85 * We've just run out of artificial frames, 86 * and we have a valid caller -- fill it in 87 * now. 88 */ 89 ASSERT(depth < pcstack_limit); 90 pcstack[depth++] = (pc_t)caller; 91 caller = NULL; 92 } 93 } else { 94 if (depth < pcstack_limit) 95 pcstack[depth++] = (pc_t)pc; 96 } 97 98 if (last) { 99 while (depth < pcstack_limit) 100 pcstack[depth++] = NULL; 101 return; 102 } 103 104 fp = nextfp; 105 minfp = fp; 106 } 107 } 108 109 static int 110 dtrace_getustack_common(uint64_t *pcstack, int pcstack_limit, uintptr_t pc, 111 uintptr_t sp) 112 { 113 klwp_t *lwp = ttolwp(curthread); 114 proc_t *p = curproc; 115 uintptr_t oldcontext = lwp->lwp_oldcontext; 116 volatile uint16_t *flags = 117 (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags; 118 size_t s1, s2; 119 int ret = 0; 120 121 ASSERT(pcstack == NULL || pcstack_limit > 0); 122 123 if (p->p_model == DATAMODEL_NATIVE) { 124 s1 = sizeof (struct frame) + 2 * sizeof (long); 125 s2 = s1 + sizeof (siginfo_t); 126 } else { 127 s1 = sizeof (struct frame32) + 3 * sizeof (int); 128 s2 = s1 + sizeof (siginfo32_t); 129 } 130 131 while (pc != 0) { 132 ret++; 133 if (pcstack != NULL) { 134 *pcstack++ = (uint64_t)pc; 135 pcstack_limit--; 136 if (pcstack_limit <= 0) 137 break; 138 } 139 140 if (sp == 0) 141 break; 142 143 if (oldcontext == sp + s1 || oldcontext == sp + s2) { 144 if (p->p_model == DATAMODEL_NATIVE) { 145 ucontext_t *ucp = (ucontext_t *)oldcontext; 146 greg_t *gregs = ucp->uc_mcontext.gregs; 147 148 sp = dtrace_fulword(&gregs[REG_FP]); 149 pc = dtrace_fulword(&gregs[REG_PC]); 150 151 oldcontext = dtrace_fulword(&ucp->uc_link); 152 } else { 153 ucontext32_t *ucp = (ucontext32_t *)oldcontext; 154 greg32_t *gregs = ucp->uc_mcontext.gregs; 155 156 sp = dtrace_fuword32(&gregs[EBP]); 157 pc = dtrace_fuword32(&gregs[EIP]); 158 159 oldcontext = dtrace_fuword32(&ucp->uc_link); 160 } 161 } else { 162 if (p->p_model == DATAMODEL_NATIVE) { 163 struct frame *fr = (struct frame *)sp; 164 165 pc = dtrace_fulword(&fr->fr_savpc); 166 sp = dtrace_fulword(&fr->fr_savfp); 167 } else { 168 struct frame32 *fr = (struct frame32 *)sp; 169 170 pc = dtrace_fuword32(&fr->fr_savpc); 171 sp = dtrace_fuword32(&fr->fr_savfp); 172 } 173 } 174 175 /* 176 * This is totally bogus: if we faulted, we're going to clear 177 * the fault and break. This is to deal with the apparently 178 * broken Java stacks on x86. 179 */ 180 if (*flags & CPU_DTRACE_FAULT) { 181 *flags &= ~CPU_DTRACE_FAULT; 182 break; 183 } 184 } 185 186 return (ret); 187 } 188 189 void 190 dtrace_getupcstack(uint64_t *pcstack, int pcstack_limit) 191 { 192 klwp_t *lwp = ttolwp(curthread); 193 proc_t *p = curproc; 194 struct regs *rp; 195 uintptr_t pc, sp; 196 volatile uint16_t *flags = 197 (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags; 198 int n; 199 200 if (*flags & CPU_DTRACE_FAULT) 201 return; 202 203 if (pcstack_limit <= 0) 204 return; 205 206 /* 207 * If there's no user context we still need to zero the stack. 208 */ 209 if (lwp == NULL || p == NULL || (rp = lwp->lwp_regs) == NULL) 210 goto zero; 211 212 *pcstack++ = (uint64_t)p->p_pid; 213 pcstack_limit--; 214 215 if (pcstack_limit <= 0) 216 return; 217 218 pc = rp->r_pc; 219 sp = rp->r_fp; 220 221 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) { 222 *pcstack++ = (uint64_t)pc; 223 pcstack_limit--; 224 if (pcstack_limit <= 0) 225 return; 226 227 if (p->p_model == DATAMODEL_NATIVE) 228 pc = dtrace_fulword((void *)rp->r_sp); 229 else 230 pc = dtrace_fuword32((void *)rp->r_sp); 231 } 232 233 n = dtrace_getustack_common(pcstack, pcstack_limit, pc, sp); 234 ASSERT(n >= 0); 235 ASSERT(n <= pcstack_limit); 236 237 pcstack += n; 238 pcstack_limit -= n; 239 240 zero: 241 while (pcstack_limit-- > 0) 242 *pcstack++ = NULL; 243 } 244 245 int 246 dtrace_getustackdepth(void) 247 { 248 klwp_t *lwp = ttolwp(curthread); 249 proc_t *p = curproc; 250 struct regs *rp; 251 uintptr_t pc, sp; 252 int n = 0; 253 254 if (lwp == NULL || p == NULL || (rp = lwp->lwp_regs) == NULL) 255 return (0); 256 257 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT)) 258 return (-1); 259 260 pc = rp->r_pc; 261 sp = rp->r_fp; 262 263 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) { 264 n++; 265 266 if (p->p_model == DATAMODEL_NATIVE) 267 pc = dtrace_fulword((void *)rp->r_sp); 268 else 269 pc = dtrace_fuword32((void *)rp->r_sp); 270 } 271 272 n += dtrace_getustack_common(NULL, 0, pc, sp); 273 274 return (n); 275 } 276 277 void 278 dtrace_getufpstack(uint64_t *pcstack, uint64_t *fpstack, int pcstack_limit) 279 { 280 klwp_t *lwp = ttolwp(curthread); 281 proc_t *p = curproc; 282 struct regs *rp; 283 uintptr_t pc, sp, oldcontext; 284 volatile uint16_t *flags = 285 (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags; 286 size_t s1, s2; 287 288 if (*flags & CPU_DTRACE_FAULT) 289 return; 290 291 if (pcstack_limit <= 0) 292 return; 293 294 /* 295 * If there's no user context we still need to zero the stack. 296 */ 297 if (lwp == NULL || p == NULL || (rp = lwp->lwp_regs) == NULL) 298 goto zero; 299 300 *pcstack++ = (uint64_t)p->p_pid; 301 pcstack_limit--; 302 303 if (pcstack_limit <= 0) 304 return; 305 306 pc = rp->r_pc; 307 sp = rp->r_fp; 308 oldcontext = lwp->lwp_oldcontext; 309 310 if (p->p_model == DATAMODEL_NATIVE) { 311 s1 = sizeof (struct frame) + 2 * sizeof (long); 312 s2 = s1 + sizeof (siginfo_t); 313 } else { 314 s1 = sizeof (struct frame32) + 3 * sizeof (int); 315 s2 = s1 + sizeof (siginfo32_t); 316 } 317 318 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) { 319 *pcstack++ = (uint64_t)pc; 320 *fpstack++ = 0; 321 pcstack_limit--; 322 if (pcstack_limit <= 0) 323 return; 324 325 if (p->p_model == DATAMODEL_NATIVE) 326 pc = dtrace_fulword((void *)rp->r_sp); 327 else 328 pc = dtrace_fuword32((void *)rp->r_sp); 329 } 330 331 while (pc != 0) { 332 *pcstack++ = (uint64_t)pc; 333 *fpstack++ = sp; 334 pcstack_limit--; 335 if (pcstack_limit <= 0) 336 break; 337 338 if (sp == 0) 339 break; 340 341 if (oldcontext == sp + s1 || oldcontext == sp + s2) { 342 if (p->p_model == DATAMODEL_NATIVE) { 343 ucontext_t *ucp = (ucontext_t *)oldcontext; 344 greg_t *gregs = ucp->uc_mcontext.gregs; 345 346 sp = dtrace_fulword(&gregs[REG_FP]); 347 pc = dtrace_fulword(&gregs[REG_PC]); 348 349 oldcontext = dtrace_fulword(&ucp->uc_link); 350 } else { 351 ucontext_t *ucp = (ucontext_t *)oldcontext; 352 greg_t *gregs = ucp->uc_mcontext.gregs; 353 354 sp = dtrace_fuword32(&gregs[EBP]); 355 pc = dtrace_fuword32(&gregs[EIP]); 356 357 oldcontext = dtrace_fuword32(&ucp->uc_link); 358 } 359 } else { 360 if (p->p_model == DATAMODEL_NATIVE) { 361 struct frame *fr = (struct frame *)sp; 362 363 pc = dtrace_fulword(&fr->fr_savpc); 364 sp = dtrace_fulword(&fr->fr_savfp); 365 } else { 366 struct frame32 *fr = (struct frame32 *)sp; 367 368 pc = dtrace_fuword32(&fr->fr_savpc); 369 sp = dtrace_fuword32(&fr->fr_savfp); 370 } 371 } 372 373 /* 374 * This is totally bogus: if we faulted, we're going to clear 375 * the fault and break. This is to deal with the apparently 376 * broken Java stacks on x86. 377 */ 378 if (*flags & CPU_DTRACE_FAULT) { 379 *flags &= ~CPU_DTRACE_FAULT; 380 break; 381 } 382 } 383 384 zero: 385 while (pcstack_limit-- > 0) 386 *pcstack++ = NULL; 387 } 388 389 /*ARGSUSED*/ 390 uint64_t 391 dtrace_getarg(int arg, int aframes) 392 { 393 uintptr_t val; 394 struct frame *fp = (struct frame *)dtrace_getfp(); 395 uintptr_t *stack; 396 int i; 397 #if defined(__amd64) 398 /* 399 * A total of 6 arguments are passed via registers; any argument with 400 * index of 5 or lower is therefore in a register. 401 */ 402 int inreg = 5; 403 #endif 404 405 for (i = 1; i <= aframes; i++) { 406 fp = (struct frame *)(fp->fr_savfp); 407 408 if (fp->fr_savpc == (pc_t)dtrace_invop_callsite) { 409 #if !defined(__amd64) 410 /* 411 * If we pass through the invalid op handler, we will 412 * use the pointer that it passed to the stack as the 413 * second argument to dtrace_invop() as the pointer to 414 * the stack. When using this stack, we must step 415 * beyond the EIP/RIP that was pushed when the trap was 416 * taken -- hence the "+ 1" below. 417 */ 418 stack = ((uintptr_t **)&fp[1])[1] + 1; 419 #else 420 /* 421 * In the case of amd64, we will use the pointer to the 422 * regs structure that was pushed when we took the 423 * trap. To get this structure, we must increment 424 * beyond the frame structure, and then again beyond 425 * the calling RIP stored in dtrace_invop(). If the 426 * argument that we're seeking is passed on the stack, 427 * we'll pull the true stack pointer out of the saved 428 * registers and decrement our argument by the number 429 * of arguments passed in registers; if the argument 430 * we're seeking is passed in regsiters, we can just 431 * load it directly. 432 */ 433 struct regs *rp = (struct regs *)((uintptr_t)&fp[1] + 434 sizeof (uintptr_t)); 435 436 if (arg <= inreg) { 437 stack = (uintptr_t *)&rp->r_rdi; 438 } else { 439 stack = (uintptr_t *)(rp->r_rsp); 440 arg -= inreg; 441 } 442 #endif 443 goto load; 444 } 445 446 } 447 448 /* 449 * We know that we did not come through a trap to get into 450 * dtrace_probe() -- the provider simply called dtrace_probe() 451 * directly. As this is the case, we need to shift the argument 452 * that we're looking for: the probe ID is the first argument to 453 * dtrace_probe(), so the argument n will actually be found where 454 * one would expect to find argument (n + 1). 455 */ 456 arg++; 457 458 #if defined(__amd64) 459 if (arg <= inreg) { 460 /* 461 * This shouldn't happen. If the argument is passed in a 462 * register then it should have been, well, passed in a 463 * register... 464 */ 465 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); 466 return (0); 467 } 468 469 arg -= (inreg + 1); 470 #endif 471 stack = (uintptr_t *)&fp[1]; 472 473 load: 474 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); 475 val = stack[arg]; 476 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); 477 478 return (val); 479 } 480 481 /*ARGSUSED*/ 482 int 483 dtrace_getstackdepth(int aframes) 484 { 485 struct frame *fp = (struct frame *)dtrace_getfp(); 486 struct frame *nextfp, *minfp, *stacktop; 487 int depth = 0; 488 int on_intr; 489 490 if ((on_intr = CPU_ON_INTR(CPU)) != 0) 491 stacktop = (struct frame *)(CPU->cpu_intr_stack + SA(MINFRAME)); 492 else 493 stacktop = (struct frame *)curthread->t_stk; 494 minfp = fp; 495 496 aframes++; 497 498 for (;;) { 499 depth++; 500 501 nextfp = (struct frame *)fp->fr_savfp; 502 503 if (nextfp <= minfp || nextfp >= stacktop) { 504 if (on_intr) { 505 /* 506 * Hop from interrupt stack to thread stack. 507 */ 508 stacktop = (struct frame *)curthread->t_stk; 509 minfp = (struct frame *)curthread->t_stkbase; 510 on_intr = 0; 511 continue; 512 } 513 break; 514 } 515 516 fp = nextfp; 517 minfp = fp; 518 } 519 520 if (depth <= aframes) 521 return (0); 522 523 return (depth - aframes); 524 } 525 526 ulong_t 527 dtrace_getreg(struct regs *rp, uint_t reg) 528 { 529 #if defined(__amd64) 530 int regmap[] = { 531 REG_GS, /* GS */ 532 REG_FS, /* FS */ 533 REG_ES, /* ES */ 534 REG_DS, /* DS */ 535 REG_RDI, /* EDI */ 536 REG_RSI, /* ESI */ 537 REG_RBP, /* EBP */ 538 REG_RSP, /* ESP */ 539 REG_RBX, /* EBX */ 540 REG_RDX, /* EDX */ 541 REG_RCX, /* ECX */ 542 REG_RAX, /* EAX */ 543 REG_TRAPNO, /* TRAPNO */ 544 REG_ERR, /* ERR */ 545 REG_RIP, /* EIP */ 546 REG_CS, /* CS */ 547 REG_RFL, /* EFL */ 548 REG_RSP, /* UESP */ 549 REG_SS /* SS */ 550 }; 551 552 if (reg <= SS) { 553 if (reg >= sizeof (regmap) / sizeof (int)) { 554 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); 555 return (0); 556 } 557 558 reg = regmap[reg]; 559 } else { 560 reg -= SS + 1; 561 } 562 563 switch (reg) { 564 case REG_RDI: 565 return (rp->r_rdi); 566 case REG_RSI: 567 return (rp->r_rsi); 568 case REG_RDX: 569 return (rp->r_rdx); 570 case REG_RCX: 571 return (rp->r_rcx); 572 case REG_R8: 573 return (rp->r_r8); 574 case REG_R9: 575 return (rp->r_r9); 576 case REG_RAX: 577 return (rp->r_rax); 578 case REG_RBX: 579 return (rp->r_rbx); 580 case REG_RBP: 581 return (rp->r_rbp); 582 case REG_R10: 583 return (rp->r_r10); 584 case REG_R11: 585 return (rp->r_r11); 586 case REG_R12: 587 return (rp->r_r12); 588 case REG_R13: 589 return (rp->r_r13); 590 case REG_R14: 591 return (rp->r_r14); 592 case REG_R15: 593 return (rp->r_r15); 594 case REG_DS: 595 return (rp->r_ds); 596 case REG_ES: 597 return (rp->r_es); 598 case REG_FS: 599 return (rp->r_fs); 600 case REG_GS: 601 return (rp->r_gs); 602 case REG_TRAPNO: 603 return (rp->r_trapno); 604 case REG_ERR: 605 return (rp->r_err); 606 case REG_RIP: 607 return (rp->r_rip); 608 case REG_CS: 609 return (rp->r_cs); 610 case REG_SS: 611 return (rp->r_ss); 612 case REG_RFL: 613 return (rp->r_rfl); 614 case REG_RSP: 615 return (rp->r_rsp); 616 default: 617 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); 618 return (0); 619 } 620 621 #else 622 if (reg > SS) { 623 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); 624 return (0); 625 } 626 627 return ((&rp->r_gs)[reg]); 628 #endif 629 } 630 631 static int 632 dtrace_copycheck(uintptr_t uaddr, uintptr_t kaddr, size_t size) 633 { 634 ASSERT(kaddr >= kernelbase && kaddr + size >= kaddr); 635 636 if (uaddr + size >= kernelbase || uaddr + size < uaddr) { 637 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 638 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = uaddr; 639 return (0); 640 } 641 642 return (1); 643 } 644 645 void 646 dtrace_copyin(uintptr_t uaddr, uintptr_t kaddr, size_t size) 647 { 648 if (dtrace_copycheck(uaddr, kaddr, size)) 649 dtrace_copy(uaddr, kaddr, size); 650 } 651 652 void 653 dtrace_copyout(uintptr_t kaddr, uintptr_t uaddr, size_t size) 654 { 655 if (dtrace_copycheck(uaddr, kaddr, size)) 656 dtrace_copy(kaddr, uaddr, size); 657 } 658 659 void 660 dtrace_copyinstr(uintptr_t uaddr, uintptr_t kaddr, size_t size) 661 { 662 if (dtrace_copycheck(uaddr, kaddr, size)) 663 dtrace_copystr(uaddr, kaddr, size); 664 } 665 666 void 667 dtrace_copyoutstr(uintptr_t kaddr, uintptr_t uaddr, size_t size) 668 { 669 if (dtrace_copycheck(uaddr, kaddr, size)) 670 dtrace_copystr(kaddr, uaddr, size); 671 } 672 673 uint8_t 674 dtrace_fuword8(void *uaddr) 675 { 676 extern uint8_t dtrace_fuword8_nocheck(void *); 677 if ((uintptr_t)uaddr >= _userlimit) { 678 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 679 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = (uintptr_t)uaddr; 680 return (0); 681 } 682 return (dtrace_fuword8_nocheck(uaddr)); 683 } 684 685 uint16_t 686 dtrace_fuword16(void *uaddr) 687 { 688 extern uint16_t dtrace_fuword16_nocheck(void *); 689 if ((uintptr_t)uaddr >= _userlimit) { 690 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 691 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = (uintptr_t)uaddr; 692 return (0); 693 } 694 return (dtrace_fuword16_nocheck(uaddr)); 695 } 696 697 uint32_t 698 dtrace_fuword32(void *uaddr) 699 { 700 extern uint32_t dtrace_fuword32_nocheck(void *); 701 if ((uintptr_t)uaddr >= _userlimit) { 702 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 703 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = (uintptr_t)uaddr; 704 return (0); 705 } 706 return (dtrace_fuword32_nocheck(uaddr)); 707 } 708 709 uint64_t 710 dtrace_fuword64(void *uaddr) 711 { 712 extern uint64_t dtrace_fuword64_nocheck(void *); 713 if ((uintptr_t)uaddr >= _userlimit) { 714 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 715 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = (uintptr_t)uaddr; 716 return (0); 717 } 718 return (dtrace_fuword64_nocheck(uaddr)); 719 } 720