1 /* $OpenBSD: kvm_i386.c,v 1.22 2012/07/09 08:43:10 deraadt Exp $ */ 2 /* $NetBSD: kvm_i386.c,v 1.9 1996/03/18 22:33:38 thorpej Exp $ */ 3 4 /*- 5 * Copyright (c) 1989, 1992, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software developed by the Computer Systems 9 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract 10 * BG 91-66 and contributed to Berkeley. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 /* 38 * i386 machine dependent routines for kvm. Hopefully, the forthcoming 39 * vm code will one day obsolete this module. 40 */ 41 42 #include <sys/param.h> 43 #include <sys/user.h> 44 #include <sys/proc.h> 45 #include <sys/stat.h> 46 #include <stdlib.h> 47 #include <unistd.h> 48 #include <nlist.h> 49 #include <kvm.h> 50 51 #include <uvm/uvm_extern.h> 52 #include <machine/vmparam.h> 53 #include <machine/pmap.h> 54 55 #include <limits.h> 56 #include <db.h> 57 58 #include "kvm_private.h" 59 60 #include <machine/pte.h> 61 62 struct vmstate { 63 pd_entry_t *PTD; 64 }; 65 66 void 67 _kvm_freevtop(kvm_t *kd) 68 { 69 if (kd->vmst != NULL) { 70 if (kd->vmst->PTD != NULL) 71 free(kd->vmst->PTD); 72 73 free(kd->vmst); 74 kd->vmst = NULL; 75 } 76 } 77 78 int 79 _kvm_initvtop(kvm_t *kd) 80 { 81 struct nlist nl[2]; 82 struct vmstate *vm; 83 u_long pa; 84 85 vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm)); 86 if (vm == NULL) 87 return (-1); 88 kd->vmst = vm; 89 90 vm->PTD = NULL; 91 92 nl[0].n_name = "_PTDpaddr"; 93 nl[1].n_name = NULL; 94 95 if (kvm_nlist(kd, nl) != 0) { 96 _kvm_err(kd, kd->program, "bad namelist"); 97 return (-1); 98 } 99 100 if (_kvm_pread(kd, kd->pmfd, &pa, sizeof pa, 101 (off_t)_kvm_pa2off(kd, nl[0].n_value - KERNBASE)) != sizeof pa) 102 goto invalid; 103 104 vm->PTD = (pd_entry_t *)_kvm_malloc(kd, PAGE_SIZE); 105 106 if (_kvm_pread(kd, kd->pmfd, vm->PTD, PAGE_SIZE, 107 (off_t)_kvm_pa2off(kd, pa)) != PAGE_SIZE) 108 goto invalid; 109 110 return (0); 111 112 invalid: 113 if (vm->PTD != NULL) { 114 free(vm->PTD); 115 vm->PTD = NULL; 116 } 117 return (-1); 118 } 119 120 /* 121 * Translate a kernel virtual address to a physical address. 122 */ 123 int 124 _kvm_kvatop(kvm_t *kd, u_long va, paddr_t *pa) 125 { 126 u_long offset, pte_pa; 127 struct vmstate *vm; 128 pt_entry_t pte; 129 130 if (!kd->vmst) { 131 _kvm_err(kd, 0, "vatop called before initvtop"); 132 return (0); 133 } 134 135 if (ISALIVE(kd)) { 136 _kvm_err(kd, 0, "vatop called in live kernel!"); 137 return (0); 138 } 139 140 vm = kd->vmst; 141 offset = va & PAGE_MASK; 142 143 /* 144 * If we are initializing (kernel page table descriptor pointer 145 * not yet set) * then return pa == va to avoid infinite recursion. 146 */ 147 if (vm->PTD == NULL) { 148 *pa = va; 149 return (PAGE_SIZE - (int)offset); 150 } 151 if ((vm->PTD[pdei(va)] & PG_V) == 0) 152 goto invalid; 153 154 pte_pa = (vm->PTD[pdei(va)] & PG_FRAME) + 155 (ptei(va) * sizeof(pt_entry_t)); 156 157 /* XXX READ PHYSICAL XXX */ 158 if (_kvm_pread(kd, kd->pmfd, &pte, sizeof pte, 159 (off_t)_kvm_pa2off(kd, pte_pa)) != sizeof pte) 160 goto invalid; 161 162 *pa = (pte & PG_FRAME) + offset; 163 return (PAGE_SIZE - (int)offset); 164 165 invalid: 166 _kvm_err(kd, 0, "invalid address (%lx)", va); 167 return (0); 168 } 169 170 /* 171 * Translate a physical address to a file-offset in the crash-dump. 172 */ 173 off_t 174 _kvm_pa2off(kvm_t *kd, paddr_t pa) 175 { 176 return ((off_t)(kd->dump_off + pa)); 177 } 178