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, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 * 22 * $FreeBSD$ 23 */ 24 /* 25 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 26 * Use is subject to license terms. 27 */ 28 #include <sys/cdefs.h> 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/kernel.h> 33 #include <sys/stack.h> 34 #include <sys/pcpu.h> 35 36 #include <machine/frame.h> 37 #include <machine/md_var.h> 38 #include <machine/reg.h> 39 #include <machine/stack.h> 40 41 #include <vm/vm.h> 42 #include <vm/vm_param.h> 43 #include <vm/pmap.h> 44 45 #include "regset.h" 46 47 uint8_t dtrace_fuword8_nocheck(void *); 48 uint16_t dtrace_fuword16_nocheck(void *); 49 uint32_t dtrace_fuword32_nocheck(void *); 50 uint64_t dtrace_fuword64_nocheck(void *); 51 52 void 53 dtrace_getpcstack(pc_t *pcstack, int pcstack_limit, int aframes, 54 uint32_t *intrpc) 55 { 56 int depth = 0; 57 register_t rbp; 58 struct amd64_frame *frame; 59 vm_offset_t callpc; 60 pc_t caller = (pc_t) solaris_cpu[curcpu].cpu_dtrace_caller; 61 62 if (intrpc != 0) 63 pcstack[depth++] = (pc_t) intrpc; 64 65 aframes++; 66 67 __asm __volatile("movq %%rbp,%0" : "=r" (rbp)); 68 69 frame = (struct amd64_frame *)rbp; 70 while (depth < pcstack_limit) { 71 if (!INKERNEL((long) frame)) 72 break; 73 74 callpc = frame->f_retaddr; 75 76 if (!INKERNEL(callpc)) 77 break; 78 79 if (aframes > 0) { 80 aframes--; 81 if ((aframes == 0) && (caller != 0)) { 82 pcstack[depth++] = caller; 83 } 84 } 85 else { 86 pcstack[depth++] = callpc; 87 } 88 89 if (frame->f_frame <= frame || 90 (vm_offset_t)frame->f_frame >= 91 (vm_offset_t)rbp + KSTACK_PAGES * PAGE_SIZE) 92 break; 93 frame = frame->f_frame; 94 } 95 96 for (; depth < pcstack_limit; depth++) { 97 pcstack[depth] = 0; 98 } 99 } 100 101 static int 102 dtrace_getustack_common(uint64_t *pcstack, int pcstack_limit, uintptr_t pc, 103 uintptr_t sp) 104 { 105 volatile uint16_t *flags = 106 (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; 107 int ret = 0; 108 109 ASSERT(pcstack == NULL || pcstack_limit > 0); 110 111 while (pc != 0) { 112 ret++; 113 if (pcstack != NULL) { 114 *pcstack++ = (uint64_t)pc; 115 pcstack_limit--; 116 if (pcstack_limit <= 0) 117 break; 118 } 119 120 if (sp == 0) 121 break; 122 123 pc = dtrace_fuword64((void *)(sp + 124 offsetof(struct amd64_frame, f_retaddr))); 125 sp = dtrace_fuword64((void *)sp); 126 127 /* 128 * This is totally bogus: if we faulted, we're going to clear 129 * the fault and break. This is to deal with the apparently 130 * broken Java stacks on x86. 131 */ 132 if (*flags & CPU_DTRACE_FAULT) { 133 *flags &= ~CPU_DTRACE_FAULT; 134 break; 135 } 136 } 137 138 return (ret); 139 } 140 141 void 142 dtrace_getupcstack(uint64_t *pcstack, int pcstack_limit) 143 { 144 proc_t *p = curproc; 145 struct trapframe *tf; 146 uintptr_t pc, sp, fp; 147 volatile uint16_t *flags = 148 (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; 149 int n; 150 151 if (*flags & CPU_DTRACE_FAULT) 152 return; 153 154 if (pcstack_limit <= 0) 155 return; 156 157 /* 158 * If there's no user context we still need to zero the stack. 159 */ 160 if (p == NULL || (tf = curthread->td_frame) == NULL) 161 goto zero; 162 163 *pcstack++ = (uint64_t)p->p_pid; 164 pcstack_limit--; 165 166 if (pcstack_limit <= 0) 167 return; 168 169 pc = tf->tf_rip; 170 fp = tf->tf_rbp; 171 sp = tf->tf_rsp; 172 173 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) { 174 /* 175 * In an entry probe. The frame pointer has not yet been 176 * pushed (that happens in the function prologue). The 177 * best approach is to add the current pc as a missing top 178 * of stack and back the pc up to the caller, which is stored 179 * at the current stack pointer address since the call 180 * instruction puts it there right before the branch. 181 */ 182 183 *pcstack++ = (uint64_t)pc; 184 pcstack_limit--; 185 if (pcstack_limit <= 0) 186 return; 187 188 pc = dtrace_fuword64((void *) sp); 189 } 190 191 n = dtrace_getustack_common(pcstack, pcstack_limit, pc, fp); 192 ASSERT(n >= 0); 193 ASSERT(n <= pcstack_limit); 194 195 pcstack += n; 196 pcstack_limit -= n; 197 198 zero: 199 while (pcstack_limit-- > 0) 200 *pcstack++ = 0; 201 } 202 203 int 204 dtrace_getustackdepth(void) 205 { 206 proc_t *p = curproc; 207 struct trapframe *tf; 208 uintptr_t pc, fp, sp; 209 int n = 0; 210 211 if (p == NULL || (tf = curthread->td_frame) == NULL) 212 return (0); 213 214 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT)) 215 return (-1); 216 217 pc = tf->tf_rip; 218 fp = tf->tf_rbp; 219 sp = tf->tf_rsp; 220 221 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) { 222 /* 223 * In an entry probe. The frame pointer has not yet been 224 * pushed (that happens in the function prologue). The 225 * best approach is to add the current pc as a missing top 226 * of stack and back the pc up to the caller, which is stored 227 * at the current stack pointer address since the call 228 * instruction puts it there right before the branch. 229 */ 230 231 pc = dtrace_fuword64((void *) sp); 232 n++; 233 } 234 235 n += dtrace_getustack_common(NULL, 0, pc, fp); 236 237 return (n); 238 } 239 240 void 241 dtrace_getufpstack(uint64_t *pcstack, uint64_t *fpstack, int pcstack_limit) 242 { 243 proc_t *p = curproc; 244 struct trapframe *tf; 245 uintptr_t pc, sp, fp; 246 volatile uint16_t *flags = 247 (volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags; 248 #ifdef notyet /* XXX signal stack */ 249 uintptr_t oldcontext; 250 size_t s1, s2; 251 #endif 252 253 if (*flags & CPU_DTRACE_FAULT) 254 return; 255 256 if (pcstack_limit <= 0) 257 return; 258 259 /* 260 * If there's no user context we still need to zero the stack. 261 */ 262 if (p == NULL || (tf = curthread->td_frame) == NULL) 263 goto zero; 264 265 *pcstack++ = (uint64_t)p->p_pid; 266 pcstack_limit--; 267 268 if (pcstack_limit <= 0) 269 return; 270 271 pc = tf->tf_rip; 272 sp = tf->tf_rsp; 273 fp = tf->tf_rbp; 274 275 #ifdef notyet /* XXX signal stack */ 276 oldcontext = lwp->lwp_oldcontext; 277 s1 = sizeof (struct xframe) + 2 * sizeof (long); 278 s2 = s1 + sizeof (siginfo_t); 279 #endif 280 281 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) { 282 *pcstack++ = (uint64_t)pc; 283 *fpstack++ = 0; 284 pcstack_limit--; 285 if (pcstack_limit <= 0) 286 return; 287 288 pc = dtrace_fuword64((void *)sp); 289 } 290 291 while (pc != 0) { 292 *pcstack++ = (uint64_t)pc; 293 *fpstack++ = fp; 294 pcstack_limit--; 295 if (pcstack_limit <= 0) 296 break; 297 298 if (fp == 0) 299 break; 300 301 #ifdef notyet /* XXX signal stack */ 302 if (oldcontext == sp + s1 || oldcontext == sp + s2) { 303 ucontext_t *ucp = (ucontext_t *)oldcontext; 304 greg_t *gregs = ucp->uc_mcontext.gregs; 305 306 sp = dtrace_fulword(&gregs[REG_FP]); 307 pc = dtrace_fulword(&gregs[REG_PC]); 308 309 oldcontext = dtrace_fulword(&ucp->uc_link); 310 } else 311 #endif /* XXX */ 312 { 313 pc = dtrace_fuword64((void *)(fp + 314 offsetof(struct amd64_frame, f_retaddr))); 315 fp = dtrace_fuword64((void *)fp); 316 } 317 318 /* 319 * This is totally bogus: if we faulted, we're going to clear 320 * the fault and break. This is to deal with the apparently 321 * broken Java stacks on x86. 322 */ 323 if (*flags & CPU_DTRACE_FAULT) { 324 *flags &= ~CPU_DTRACE_FAULT; 325 break; 326 } 327 } 328 329 zero: 330 while (pcstack_limit-- > 0) 331 *pcstack++ = 0; 332 } 333 334 /*ARGSUSED*/ 335 uint64_t 336 dtrace_getarg(int arg, int aframes) 337 { 338 uintptr_t val; 339 struct amd64_frame *fp = (struct amd64_frame *)dtrace_getfp(); 340 uintptr_t *stack; 341 int i; 342 343 /* 344 * A total of 6 arguments are passed via registers; any argument with 345 * index of 5 or lower is therefore in a register. 346 */ 347 int inreg = 5; 348 349 for (i = 1; i <= aframes; i++) { 350 fp = fp->f_frame; 351 352 if (P2ROUNDUP(fp->f_retaddr, 16) == 353 (long)dtrace_invop_callsite) { 354 /* 355 * In the case of amd64, we will use the pointer to the 356 * regs structure that was pushed when we took the 357 * trap. To get this structure, we must increment 358 * beyond the frame structure, and then again beyond 359 * the calling RIP stored in dtrace_invop(). If the 360 * argument that we're seeking is passed on the stack, 361 * we'll pull the true stack pointer out of the saved 362 * registers and decrement our argument by the number 363 * of arguments passed in registers; if the argument 364 * we're seeking is passed in regsiters, we can just 365 * load it directly. 366 */ 367 struct trapframe *tf = 368 (struct trapframe *)((uintptr_t)&fp[1]); 369 370 if (arg <= inreg) { 371 switch (arg) { 372 case 0: 373 stack = (uintptr_t *)&tf->tf_rdi; 374 break; 375 case 1: 376 stack = (uintptr_t *)&tf->tf_rsi; 377 break; 378 case 2: 379 stack = (uintptr_t *)&tf->tf_rdx; 380 break; 381 case 3: 382 stack = (uintptr_t *)&tf->tf_rcx; 383 break; 384 case 4: 385 stack = (uintptr_t *)&tf->tf_r8; 386 break; 387 case 5: 388 stack = (uintptr_t *)&tf->tf_r9; 389 break; 390 } 391 arg = 0; 392 } else { 393 stack = (uintptr_t *)(tf->tf_rsp); 394 arg -= inreg; 395 } 396 goto load; 397 } 398 399 } 400 401 /* 402 * We know that we did not come through a trap to get into 403 * dtrace_probe() -- the provider simply called dtrace_probe() 404 * directly. As this is the case, we need to shift the argument 405 * that we're looking for: the probe ID is the first argument to 406 * dtrace_probe(), so the argument n will actually be found where 407 * one would expect to find argument (n + 1). 408 */ 409 arg++; 410 411 if (arg <= inreg) { 412 /* 413 * This shouldn't happen. If the argument is passed in a 414 * register then it should have been, well, passed in a 415 * register... 416 */ 417 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); 418 return (0); 419 } 420 421 arg -= (inreg + 1); 422 stack = (uintptr_t *)fp + 2; 423 424 load: 425 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); 426 val = stack[arg]; 427 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); 428 429 return (val); 430 return (0); 431 } 432 433 int 434 dtrace_getstackdepth(int aframes) 435 { 436 int depth = 0; 437 struct amd64_frame *frame; 438 vm_offset_t rbp; 439 440 aframes++; 441 rbp = dtrace_getfp(); 442 frame = (struct amd64_frame *)rbp; 443 depth++; 444 for(;;) { 445 if (!INKERNEL((long) frame)) 446 break; 447 if (!INKERNEL((long) frame->f_frame)) 448 break; 449 depth++; 450 if (frame->f_frame <= frame || 451 (vm_offset_t)frame->f_frame >= 452 (vm_offset_t)rbp + KSTACK_PAGES * PAGE_SIZE) 453 break; 454 frame = frame->f_frame; 455 } 456 if (depth < aframes) 457 return 0; 458 else 459 return depth - aframes; 460 } 461 462 ulong_t 463 dtrace_getreg(struct trapframe *rp, uint_t reg) 464 { 465 /* This table is dependent on reg.d. */ 466 int regmap[] = { 467 REG_GS, /* 0 GS */ 468 REG_FS, /* 1 FS */ 469 REG_ES, /* 2 ES */ 470 REG_DS, /* 3 DS */ 471 REG_RDI, /* 4 EDI */ 472 REG_RSI, /* 5 ESI */ 473 REG_RBP, /* 6 EBP, REG_FP */ 474 REG_RSP, /* 7 ESP */ 475 REG_RBX, /* 8 EBX, REG_R1 */ 476 REG_RDX, /* 9 EDX */ 477 REG_RCX, /* 10 ECX */ 478 REG_RAX, /* 11 EAX, REG_R0 */ 479 REG_TRAPNO, /* 12 TRAPNO */ 480 REG_ERR, /* 13 ERR */ 481 REG_RIP, /* 14 EIP, REG_PC */ 482 REG_CS, /* 15 CS */ 483 REG_RFL, /* 16 EFL, REG_PS */ 484 REG_RSP, /* 17 UESP, REG_SP */ 485 REG_SS /* 18 SS */ 486 }; 487 488 if (reg <= SS) { 489 if (reg >= sizeof (regmap) / sizeof (int)) { 490 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); 491 return (0); 492 } 493 494 reg = regmap[reg]; 495 } else { 496 /* This is dependent on reg.d. */ 497 reg -= SS + 1; 498 } 499 500 switch (reg) { 501 case REG_RDI: 502 return (rp->tf_rdi); 503 case REG_RSI: 504 return (rp->tf_rsi); 505 case REG_RDX: 506 return (rp->tf_rdx); 507 case REG_RCX: 508 return (rp->tf_rcx); 509 case REG_R8: 510 return (rp->tf_r8); 511 case REG_R9: 512 return (rp->tf_r9); 513 case REG_RAX: 514 return (rp->tf_rax); 515 case REG_RBX: 516 return (rp->tf_rbx); 517 case REG_RBP: 518 return (rp->tf_rbp); 519 case REG_R10: 520 return (rp->tf_r10); 521 case REG_R11: 522 return (rp->tf_r11); 523 case REG_R12: 524 return (rp->tf_r12); 525 case REG_R13: 526 return (rp->tf_r13); 527 case REG_R14: 528 return (rp->tf_r14); 529 case REG_R15: 530 return (rp->tf_r15); 531 case REG_DS: 532 return (rp->tf_ds); 533 case REG_ES: 534 return (rp->tf_es); 535 case REG_FS: 536 return (rp->tf_fs); 537 case REG_GS: 538 return (rp->tf_gs); 539 case REG_TRAPNO: 540 return (rp->tf_trapno); 541 case REG_ERR: 542 return (rp->tf_err); 543 case REG_RIP: 544 return (rp->tf_rip); 545 case REG_CS: 546 return (rp->tf_cs); 547 case REG_SS: 548 return (rp->tf_ss); 549 case REG_RFL: 550 return (rp->tf_rflags); 551 case REG_RSP: 552 return (rp->tf_rsp); 553 default: 554 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); 555 return (0); 556 } 557 } 558 559 static int 560 dtrace_copycheck(uintptr_t uaddr, uintptr_t kaddr, size_t size) 561 { 562 ASSERT(INKERNEL(kaddr) && kaddr + size >= kaddr); 563 564 if (uaddr + size > VM_MAXUSER_ADDRESS || uaddr + size < uaddr) { 565 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 566 cpu_core[curcpu].cpuc_dtrace_illval = uaddr; 567 return (0); 568 } 569 570 return (1); 571 } 572 573 void 574 dtrace_copyin(uintptr_t uaddr, uintptr_t kaddr, size_t size, 575 volatile uint16_t *flags) 576 { 577 if (dtrace_copycheck(uaddr, kaddr, size)) 578 dtrace_copy(uaddr, kaddr, size); 579 } 580 581 void 582 dtrace_copyout(uintptr_t kaddr, uintptr_t uaddr, size_t size, 583 volatile uint16_t *flags) 584 { 585 if (dtrace_copycheck(uaddr, kaddr, size)) 586 dtrace_copy(kaddr, uaddr, size); 587 } 588 589 void 590 dtrace_copyinstr(uintptr_t uaddr, uintptr_t kaddr, size_t size, 591 volatile uint16_t *flags) 592 { 593 if (dtrace_copycheck(uaddr, kaddr, size)) 594 dtrace_copystr(uaddr, kaddr, size, flags); 595 } 596 597 void 598 dtrace_copyoutstr(uintptr_t kaddr, uintptr_t uaddr, size_t size, 599 volatile uint16_t *flags) 600 { 601 if (dtrace_copycheck(uaddr, kaddr, size)) 602 dtrace_copystr(kaddr, uaddr, size, flags); 603 } 604 605 uint8_t 606 dtrace_fuword8(void *uaddr) 607 { 608 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 609 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 610 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 611 return (0); 612 } 613 return (dtrace_fuword8_nocheck(uaddr)); 614 } 615 616 uint16_t 617 dtrace_fuword16(void *uaddr) 618 { 619 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 620 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 621 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 622 return (0); 623 } 624 return (dtrace_fuword16_nocheck(uaddr)); 625 } 626 627 uint32_t 628 dtrace_fuword32(void *uaddr) 629 { 630 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 631 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 632 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 633 return (0); 634 } 635 return (dtrace_fuword32_nocheck(uaddr)); 636 } 637 638 uint64_t 639 dtrace_fuword64(void *uaddr) 640 { 641 if ((uintptr_t)uaddr > VM_MAXUSER_ADDRESS) { 642 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); 643 cpu_core[curcpu].cpuc_dtrace_illval = (uintptr_t)uaddr; 644 return (0); 645 } 646 return (dtrace_fuword64_nocheck(uaddr)); 647 } 648