kvm_i386.c revision 147678
11602Srgrimes/*- 21602Srgrimes * Copyright (c) 1989, 1992, 1993 31602Srgrimes * The Regents of the University of California. All rights reserved. 41602Srgrimes * 51602Srgrimes * This code is derived from software developed by the Computer Systems 61602Srgrimes * Engineering group at Lawrence Berkeley Laboratory under DARPA contract 71602Srgrimes * BG 91-66 and contributed to Berkeley. 81602Srgrimes * 91602Srgrimes * Redistribution and use in source and binary forms, with or without 101602Srgrimes * modification, are permitted provided that the following conditions 111602Srgrimes * are met: 121602Srgrimes * 1. Redistributions of source code must retain the above copyright 131602Srgrimes * notice, this list of conditions and the following disclaimer. 141602Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 151602Srgrimes * notice, this list of conditions and the following disclaimer in the 161602Srgrimes * documentation and/or other materials provided with the distribution. 171602Srgrimes * 3. All advertising materials mentioning features or use of this software 181602Srgrimes * must display the following acknowledgement: 191602Srgrimes * This product includes software developed by the University of 201602Srgrimes * California, Berkeley and its contributors. 211602Srgrimes * 4. Neither the name of the University nor the names of its contributors 221602Srgrimes * may be used to endorse or promote products derived from this software 231602Srgrimes * without specific prior written permission. 241602Srgrimes * 251602Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 261602Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 271602Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 281602Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 291602Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 301602Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 311602Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 321602Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 331602Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 341602Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 351602Srgrimes * SUCH DAMAGE. 361602Srgrimes */ 371602Srgrimes 3883551Sdillon#include <sys/cdefs.h> 3983551Sdillon__FBSDID("$FreeBSD: head/lib/libkvm/kvm_i386.c 147678 2005-06-30 01:25:21Z ps $"); 4083551Sdillon 411602Srgrimes#if defined(LIBC_SCCS) && !defined(lint) 4255127Speter#if 0 431602Srgrimesstatic char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93"; 4455127Speter#endif 451602Srgrimes#endif /* LIBC_SCCS and not lint */ 461602Srgrimes 471602Srgrimes/* 488870Srgrimes * i386 machine dependent routines for kvm. Hopefully, the forthcoming 491602Srgrimes * vm code will one day obsolete this module. 501602Srgrimes */ 511602Srgrimes 521602Srgrimes#include <sys/param.h> 531602Srgrimes#include <sys/user.h> 541602Srgrimes#include <sys/proc.h> 551602Srgrimes#include <sys/stat.h> 56147672Speter#include <sys/mman.h> 5717141Sjkh#include <stdlib.h> 581602Srgrimes#include <unistd.h> 591602Srgrimes#include <nlist.h> 601602Srgrimes#include <kvm.h> 611602Srgrimes 621602Srgrimes#include <vm/vm.h> 631602Srgrimes#include <vm/vm_param.h> 641602Srgrimes 65147672Speter#include <machine/elf.h> 66147672Speter 671602Srgrimes#include <limits.h> 681602Srgrimes 691602Srgrimes#include "kvm_private.h" 701602Srgrimes 711602Srgrimes#ifndef btop 721603Srgrimes#define btop(x) (i386_btop(x)) 731603Srgrimes#define ptob(x) (i386_ptob(x)) 741602Srgrimes#endif 751602Srgrimes 76147672Speter#define PG_FRAME_PAE (~((uint64_t)PAGE_MASK)) 77147672Speter#define PDRSHIFT_PAE 21 78147672Speter#define NPTEPG_PAE (PAGE_SIZE/sizeof(uint64_t)) 79147672Speter#define NBPDR_PAE (1<<PDRSHIFT_PAE) 80147672Speter 811602Srgrimesstruct vmstate { 82147672Speter void *mmapbase; 83147672Speter size_t mmapsize; 84147672Speter void *PTD; 85147672Speter int pae; 861602Srgrimes}; 871602Srgrimes 88147672Speter/* 89147672Speter * Map the ELF headers into the process' address space. We do this in two 90147672Speter * steps: first the ELF header itself and using that information the whole 91147672Speter * set of headers. (Taken from kvm_ia64.c) 92147672Speter */ 93147672Speterstatic int 94147672Speter_kvm_maphdrs(kvm_t *kd, size_t sz) 95147672Speter{ 96147672Speter struct vmstate *vm = kd->vmst; 97147672Speter 98147672Speter /* munmap() previous mmap(). */ 99147672Speter if (vm->mmapbase != NULL) { 100147672Speter munmap(vm->mmapbase, vm->mmapsize); 101147672Speter vm->mmapbase = NULL; 102147672Speter } 103147672Speter 104147672Speter vm->mmapsize = sz; 105147672Speter vm->mmapbase = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 106147672Speter if (vm->mmapbase == MAP_FAILED) { 107147672Speter _kvm_err(kd, kd->program, "cannot mmap corefile"); 108147672Speter return (-1); 109147672Speter } 110147672Speter return (0); 111147672Speter} 112147672Speter 113147672Speter/* 114147672Speter * Translate a physical memory address to a file-offset in the crash-dump. 115147672Speter * (Taken from kvm_ia64.c) 116147672Speter */ 117147672Speterstatic size_t 118147672Speter_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs) 119147672Speter{ 120147672Speter Elf_Ehdr *e = kd->vmst->mmapbase; 121147672Speter Elf_Phdr *p = (Elf_Phdr*)((char*)e + e->e_phoff); 122147672Speter int n = e->e_phnum; 123147672Speter 124147672Speter while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz)) 125147672Speter p++, n--; 126147672Speter if (n == 0) 127147672Speter return (0); 128147672Speter *ofs = (pa - p->p_paddr) + p->p_offset; 129147672Speter return (PAGE_SIZE - ((size_t)pa & PAGE_MASK)); 130147672Speter} 131147672Speter 1321602Srgrimesvoid 13318798Speter_kvm_freevtop(kvm_t *kd) 13418798Speter{ 135147672Speter struct vmstate *vm = kd->vmst; 136147672Speter 137147672Speter if (vm->mmapbase != NULL) 138147672Speter munmap(vm->mmapbase, vm->mmapsize); 139147672Speter if (vm->PTD) 140147672Speter free(vm->PTD); 141147672Speter free(vm); 142147672Speter kd->vmst = NULL; 1431602Srgrimes} 1441602Srgrimes 1451602Srgrimesint 14618798Speter_kvm_initvtop(kvm_t *kd) 14718798Speter{ 1481603Srgrimes struct nlist nlist[2]; 14918798Speter u_long pa; 15082263Speter u_long kernbase; 151147672Speter char *PTD; 152147672Speter Elf_Ehdr *ehdr; 153147672Speter size_t hdrsz; 154147672Speter int i; 1551602Srgrimes 156147672Speter kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst)); 157147672Speter if (kd->vmst == 0) { 1581603Srgrimes _kvm_err(kd, kd->program, "cannot allocate vm"); 1591602Srgrimes return (-1); 1601603Srgrimes } 161147672Speter kd->vmst->PTD = 0; 1621602Srgrimes 163147672Speter if (_kvm_maphdrs(kd, sizeof(Elf_Ehdr)) == -1) 164147672Speter return (-1); 165147672Speter 166147672Speter ehdr = kd->vmst->mmapbase; 167147672Speter hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum; 168147672Speter if (_kvm_maphdrs(kd, hdrsz) == -1) 169147672Speter return (-1); 170147672Speter 17182263Speter nlist[0].n_name = "kernbase"; 1721603Srgrimes nlist[1].n_name = 0; 1731602Srgrimes 17482263Speter if (kvm_nlist(kd, nlist) != 0) 17582263Speter kernbase = KERNBASE; /* for old kernels */ 17682263Speter else 17782263Speter kernbase = nlist[0].n_value; 17882263Speter 179147672Speter nlist[0].n_name = "IdlePDPT"; 18082263Speter nlist[1].n_name = 0; 18182263Speter 182147672Speter if (kvm_nlist(kd, nlist) == 0) { 183147672Speter uint64_t pa64; 184147672Speter 185147672Speter if (kvm_read(kd, (nlist[0].n_value - kernbase), &pa, 186147672Speter sizeof(pa)) != sizeof(pa)) { 187147672Speter _kvm_err(kd, kd->program, "cannot read IdlePDPT"); 188147672Speter return (-1); 189147672Speter } 190147672Speter PTD = _kvm_malloc(kd, 4 * PAGE_SIZE); 191147672Speter for (i = 0; i < 4; i++) { 192147672Speter if (kvm_read(kd, pa + (i * sizeof(pa64)), &pa64, 193147672Speter sizeof(pa64)) != sizeof(pa64)) { 194147672Speter _kvm_err(kd, kd->program, "Cannot read PDPT"); 195147672Speter free(PTD); 196147672Speter return (-1); 197147672Speter } 198147672Speter if (kvm_read(kd, pa64 & PG_FRAME_PAE, 199147672Speter PTD + (i * PAGE_SIZE), PAGE_SIZE) != (PAGE_SIZE)) { 200147672Speter _kvm_err(kd, kd->program, "cannot read PDPT"); 201147672Speter free(PTD); 202147672Speter return (-1); 203147672Speter } 204147672Speter } 205147672Speter kd->vmst->PTD = PTD; 206147672Speter kd->vmst->pae = 1; 207147672Speter } else { 208147672Speter nlist[0].n_name = "IdlePTD"; 209147672Speter nlist[1].n_name = 0; 210147672Speter 211147672Speter if (kvm_nlist(kd, nlist) != 0) { 212147672Speter _kvm_err(kd, kd->program, "bad namelist"); 213147672Speter return (-1); 214147672Speter } 215147672Speter if (kvm_read(kd, (nlist[0].n_value - kernbase), &pa, 216147672Speter sizeof(pa)) != sizeof(pa)) { 217147672Speter _kvm_err(kd, kd->program, "cannot read IdlePTD"); 218147672Speter return (-1); 219147672Speter } 220147672Speter PTD = _kvm_malloc(kd, PAGE_SIZE); 221147672Speter if (kvm_read(kd, pa, PTD, PAGE_SIZE) != PAGE_SIZE) { 222147672Speter _kvm_err(kd, kd->program, "cannot read PTD"); 223147672Speter return (-1); 224147672Speter } 225147672Speter kd->vmst->PTD = PTD; 226147672Speter return (0); 227147672Speter kd->vmst->pae = 0; 2281602Srgrimes } 2291602Srgrimes return (0); 2301602Srgrimes} 2311602Srgrimes 2321602Srgrimesstatic int 233147672Speter_kvm_vatop(kvm_t *kd, u_long va, off_t *pa) 23418798Speter{ 23518798Speter struct vmstate *vm; 23618798Speter u_long offset; 23718798Speter u_long pte_pa; 238147672Speter u_long pde_pa; 23918798Speter pd_entry_t pde; 24018798Speter pt_entry_t pte; 24118798Speter u_long pdeindex; 24218798Speter u_long pteindex; 243147672Speter size_t s; 244147672Speter u_long a; 245147672Speter off_t ofs; 246147672Speter uint32_t *PTD; 2471602Srgrimes 24818798Speter vm = kd->vmst; 249147672Speter PTD = (uint32_t *)vm->PTD; 25018798Speter offset = va & (PAGE_SIZE - 1); 25118798Speter 25218798Speter /* 25318798Speter * If we are initializing (kernel page table descriptor pointer 25418798Speter * not yet set) then return pa == va to avoid infinite recursion. 25518798Speter */ 256147672Speter if (PTD == 0) { 257147672Speter s = _kvm_pa2off(kd, va, pa); 258147672Speter if (s == 0) { 259147672Speter _kvm_err(kd, kd->program, 260147672Speter "_kvm_vatop: bootstrap data not in dump"); 261147672Speter goto invalid; 262147672Speter } else 263147672Speter return (PAGE_SIZE - offset); 26418798Speter } 26518798Speter 26618798Speter pdeindex = va >> PDRSHIFT; 267147672Speter pde = PTD[pdeindex]; 268147672Speter if (((u_long)pde & PG_V) == 0) { 269147672Speter _kvm_err(kd, kd->program, "_kvm_vatop: pde not valid"); 27018798Speter goto invalid; 271147672Speter } 27218798Speter 27328318Stegge if ((u_long)pde & PG_PS) { 27428318Stegge /* 27528318Stegge * No second-level page table; ptd describes one 4MB page. 27628318Stegge * (We assume that the kernel wouldn't set PG_PS without enabling 277147672Speter * it cr0). 27828318Stegge */ 27928318Stegge#define PAGE4M_MASK (NBPDR - 1) 28028318Stegge#define PG_FRAME4M (~PAGE4M_MASK) 281147672Speter pde_pa = ((u_long)pde & PG_FRAME4M) + (va & PAGE4M_MASK); 282147672Speter s = _kvm_pa2off(kd, pde_pa, &ofs); 283147672Speter if (s <= sizeof pde) { 284147672Speter _kvm_syserr(kd, kd->program, 285147672Speter "_kvm_vatop: pde_pa not found"); 286147672Speter goto invalid; 287147672Speter } 288147672Speter *pa = ofs; 28928318Stegge return (NBPDR - (va & PAGE4M_MASK)); 29028318Stegge } 29128318Stegge 29218798Speter pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1); 293147672Speter pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pde)); 29418798Speter 295147672Speter s = _kvm_pa2off(kd, pte_pa, &ofs); 296147672Speter if (s <= sizeof pte) { 297147672Speter _kvm_err(kd, kd->program, "_kvm_vatop: pdpe_pa not found"); 298147672Speter goto invalid; 299147672Speter } 300147672Speter 30118798Speter /* XXX This has to be a physical address read, kvm_read is virtual */ 302147672Speter if (lseek(kd->pmfd, ofs, 0) == -1) { 30318798Speter _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek"); 30418798Speter goto invalid; 30518798Speter } 30618798Speter if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) { 30718798Speter _kvm_syserr(kd, kd->program, "_kvm_vatop: read"); 30818798Speter goto invalid; 30918798Speter } 310147672Speter if (((u_long)pte & PG_V) == 0) { 311147672Speter _kvm_err(kd, kd->program, "_kvm_kvatop: pte not valid"); 31218798Speter goto invalid; 313147672Speter } 31418798Speter 315147672Speter a = ((u_long)pte & PG_FRAME) + offset; 316147672Speter s =_kvm_pa2off(kd, a, pa); 317147672Speter if (s == 0) { 318147672Speter _kvm_err(kd, kd->program, "_kvm_vatop: address not in dump"); 319147672Speter goto invalid; 320147672Speter } else 321147672Speter return (PAGE_SIZE - offset); 32218798Speter 32318798Speterinvalid: 324147672Speter _kvm_err(kd, 0, "invalid address (0x%lx)", va); 32518798Speter return (0); 3261602Srgrimes} 3271602Srgrimes 328147672Speterstatic int 329147672Speter_kvm_vatop_pae(kvm_t *kd, u_long va, off_t *pa) 330147672Speter{ 331147672Speter struct vmstate *vm; 332147672Speter uint64_t offset; 333147672Speter uint64_t pte_pa; 334147672Speter uint64_t pde_pa; 335147672Speter uint64_t pde; 336147672Speter uint64_t pte; 337147672Speter u_long pdeindex; 338147672Speter u_long pteindex; 339147672Speter size_t s; 340147672Speter uint64_t a; 341147672Speter off_t ofs; 342147672Speter uint64_t *PTD; 343147672Speter 344147672Speter vm = kd->vmst; 345147672Speter PTD = (uint64_t *)vm->PTD; 346147672Speter offset = va & (PAGE_SIZE - 1); 347147672Speter 348147672Speter /* 349147672Speter * If we are initializing (kernel page table descriptor pointer 350147672Speter * not yet set) then return pa == va to avoid infinite recursion. 351147672Speter */ 352147672Speter if (PTD == 0) { 353147672Speter s = _kvm_pa2off(kd, va, pa); 354147672Speter if (s == 0) { 355147672Speter _kvm_err(kd, kd->program, 356147672Speter "_kvm_vatop_pae: bootstrap data not in dump"); 357147672Speter goto invalid; 358147672Speter } else 359147672Speter return (PAGE_SIZE - offset); 360147672Speter } 361147672Speter 362147672Speter pdeindex = va >> PDRSHIFT_PAE; 363147672Speter pde = PTD[pdeindex]; 364147672Speter if (((u_long)pde & PG_V) == 0) { 365147672Speter _kvm_err(kd, kd->program, "_kvm_kvatop_pae: pde not valid"); 366147672Speter goto invalid; 367147672Speter } 368147672Speter 369147672Speter if ((u_long)pde & PG_PS) { 370147672Speter /* 371147672Speter * No second-level page table; ptd describes one 2MB page. 372147672Speter * (We assume that the kernel wouldn't set PG_PS without enabling 373147672Speter * it cr0). 374147672Speter */ 375147672Speter#define PAGE2M_MASK (NBPDR_PAE - 1) 376147672Speter#define PG_FRAME2M (~PAGE2M_MASK) 377147672Speter pde_pa = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK); 378147672Speter s = _kvm_pa2off(kd, pde_pa, &ofs); 379147672Speter if (s <= sizeof pde) { 380147672Speter _kvm_syserr(kd, kd->program, 381147672Speter "_kvm_vatop_pae: pde_pa not found"); 382147672Speter goto invalid; 383147672Speter } 384147672Speter *pa = ofs; 385147672Speter return (NBPDR_PAE - (va & PAGE2M_MASK)); 386147672Speter } 387147672Speter 388147672Speter pteindex = (va >> PAGE_SHIFT) & (NPTEPG_PAE-1); 389147672Speter pte_pa = ((uint64_t)pde & PG_FRAME_PAE) + (pteindex * sizeof(pde)); 390147672Speter 391147672Speter s = _kvm_pa2off(kd, pte_pa, &ofs); 392147672Speter if (s <= sizeof pte) { 393147672Speter _kvm_err(kd, kd->program, "_kvm_vatop_pae: pdpe_pa not found"); 394147672Speter goto invalid; 395147672Speter } 396147672Speter 397147672Speter /* XXX This has to be a physical address read, kvm_read is virtual */ 398147672Speter if (lseek(kd->pmfd, ofs, 0) == -1) { 399147672Speter _kvm_syserr(kd, kd->program, "_kvm_vatop_pae: lseek"); 400147672Speter goto invalid; 401147672Speter } 402147672Speter if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) { 403147672Speter _kvm_syserr(kd, kd->program, "_kvm_vatop_pae: read"); 404147672Speter goto invalid; 405147672Speter } 406147672Speter if (((uint64_t)pte & PG_V) == 0) { 407147672Speter _kvm_err(kd, kd->program, "_kvm_vatop_pae: pte not valid"); 408147672Speter goto invalid; 409147672Speter } 410147672Speter 411147672Speter a = ((uint64_t)pte & PG_FRAME_PAE) + offset; 412147672Speter s =_kvm_pa2off(kd, a, pa); 413147672Speter if (s == 0) { 414147672Speter _kvm_err(kd, kd->program, 415147672Speter "_kvm_vatop_pae: address not in dump"); 416147672Speter goto invalid; 417147672Speter } else 418147672Speter return (PAGE_SIZE - offset); 419147672Speter 420147672Speterinvalid: 421147672Speter _kvm_err(kd, 0, "invalid address (0x%lx)", va); 422147672Speter return (0); 423147672Speter} 424147672Speter 4251602Srgrimesint 426147678Sps_kvm_kvatop(kvm_t *kd, u_long va, off_t *pa) 42718798Speter{ 428147672Speter 429147672Speter if (ISALIVE(kd)) { 430147672Speter _kvm_err(kd, 0, "vatop called in live kernel!"); 431147672Speter return (0); 432147672Speter } 433147672Speter if (kd->vmst->pae) 434147672Speter return (_kvm_vatop_pae(kd, va, pa)); 435147672Speter else 436147672Speter return (_kvm_vatop(kd, va, pa)); 4371602Srgrimes} 438