1 /* $NetBSD: kvm_i386.c,v 1.29 2010/10/05 23:48:16 jym Exp $ */ 2 3 /*- 4 * Copyright (c) 1989, 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software developed by the Computer Systems 8 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract 9 * BG 91-66 and contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: kvm_i386.c,v 1.29 2010/10/05 23:48:16 jym Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 /* 46 * i386 machine dependent routines for kvm. 47 */ 48 49 #include <sys/param.h> 50 #include <sys/user.h> 51 #include <sys/stat.h> 52 #include <sys/kcore.h> 53 #include <sys/types.h> 54 55 #include <stdlib.h> 56 #include <unistd.h> 57 #include <nlist.h> 58 #include <kvm.h> 59 60 #include <uvm/uvm_extern.h> 61 62 #include <limits.h> 63 #include <db.h> 64 65 #include "kvm_private.h" 66 67 #include <i386/kcore.h> 68 #include <i386/pmap.h> 69 #include <i386/pte.h> 70 #include <i386/vmparam.h> 71 72 #ifndef btop 73 #define btop(x) (((unsigned)(x)) >> PGSHIFT) /* XXX */ 74 #define ptob(x) ((caddr_t)((x) << PGSHIFT)) /* XXX */ 75 #endif 76 77 /* 78 * Indicates whether PAE is in use for the kernel image 79 * 0: native i386 memory mappings 80 * 1: i386 PAE mappings 81 */ 82 static int i386_use_pae; 83 84 int _kvm_kvatop_i386(kvm_t *, vaddr_t, paddr_t *); 85 int _kvm_kvatop_i386pae(kvm_t *, vaddr_t, paddr_t *); 86 87 void 88 _kvm_freevtop(kvm_t *kd) 89 { 90 91 /* Not actually used for anything right now, but safe. */ 92 if (kd->vmst != 0) 93 free(kd->vmst); 94 } 95 96 /*ARGSUSED*/ 97 int 98 _kvm_initvtop(kvm_t *kd) 99 { 100 cpu_kcore_hdr_t *cpu_kh = kd->cpu_data; 101 102 i386_use_pae = 0; /* default: non PAE mode */ 103 if ((cpu_kh->pdppaddr & I386_KCORE_PAE) == I386_KCORE_PAE) 104 i386_use_pae = 1; 105 106 return 0; 107 } 108 109 /* 110 * Translate a kernel virtual address to a physical address. 111 */ 112 int 113 _kvm_kvatop(kvm_t *kd, vaddr_t va, paddr_t *pa) 114 { 115 116 if (ISALIVE(kd)) { 117 _kvm_err(kd, 0, "vatop called in live kernel!"); 118 return 0; 119 } 120 121 switch (i386_use_pae) { 122 default: 123 case 0: 124 return _kvm_kvatop_i386(kd, va, pa); 125 case 1: 126 return _kvm_kvatop_i386pae(kd, va, pa); 127 } 128 129 } 130 131 /* 132 * Used to translate a virtual address to a physical address for systems 133 * with PAE mode disabled. Only two levels of virtual memory pages are 134 * dereferenced (L2 PDEs, then L1 PTEs). 135 */ 136 int 137 _kvm_kvatop_i386(kvm_t *kd, vaddr_t va, paddr_t *pa) 138 { 139 cpu_kcore_hdr_t *cpu_kh; 140 u_long page_off; 141 pd_entry_t pde; 142 pt_entry_t pte; 143 paddr_t pde_pa, pte_pa; 144 145 cpu_kh = kd->cpu_data; 146 page_off = va & PGOFSET; 147 148 /* 149 * Find and read the page directory entry. 150 * pdppaddr being PAGE_SIZE aligned, we mask the option bits. 151 */ 152 pde_pa = (cpu_kh->pdppaddr & PG_FRAME) + (pl2_pi(va) * sizeof(pde)); 153 if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde), 154 _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) { 155 _kvm_syserr(kd, 0, "could not read PDE"); 156 goto lose; 157 } 158 159 /* 160 * Find and read the page table entry. 161 */ 162 if ((pde & PG_V) == 0) { 163 _kvm_err(kd, 0, "invalid translation (invalid PDE)"); 164 goto lose; 165 } 166 if ((pde & PG_PS) != 0) { 167 /* 168 * This is a 4MB page. 169 */ 170 page_off = va & ~PG_LGFRAME; 171 *pa = (pde & PG_LGFRAME) + page_off; 172 return (int)(NBPD_L2 - page_off); 173 } 174 pte_pa = (pde & PG_FRAME) + (pl1_pi(va) * sizeof(pt_entry_t)); 175 if (_kvm_pread(kd, kd->pmfd, (void *) &pte, sizeof(pte), 176 _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) { 177 _kvm_syserr(kd, 0, "could not read PTE"); 178 goto lose; 179 } 180 181 /* 182 * Validate the PTE and return the physical address. 183 */ 184 if ((pte & PG_V) == 0) { 185 _kvm_err(kd, 0, "invalid translation (invalid PTE)"); 186 goto lose; 187 } 188 *pa = (pte & PG_FRAME) + page_off; 189 return (int)(NBPG - page_off); 190 191 lose: 192 *pa = (paddr_t)~0L; 193 return 0; 194 } 195 196 /* 197 * Translate a physical address to a file-offset in the crash dump. 198 */ 199 off_t 200 _kvm_pa2off(kvm_t *kd, paddr_t pa) 201 { 202 cpu_kcore_hdr_t *cpu_kh; 203 phys_ram_seg_t *ramsegs; 204 off_t off; 205 int i; 206 207 cpu_kh = kd->cpu_data; 208 ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh)); 209 210 off = 0; 211 for (i = 0; i < cpu_kh->nmemsegs; i++) { 212 if (pa >= ramsegs[i].start && 213 (pa - ramsegs[i].start) < ramsegs[i].size) { 214 off += (pa - ramsegs[i].start); 215 break; 216 } 217 off += ramsegs[i].size; 218 } 219 220 return (kd->dump_off + off); 221 } 222 223 /* 224 * Machine-dependent initialization for ALL open kvm descriptors, 225 * not just those for a kernel crash dump. Some architectures 226 * have to deal with these NOT being constants! (i.e. m68k) 227 */ 228 int 229 _kvm_mdopen(kvm_t *kd) 230 { 231 232 kd->usrstack = USRSTACK; 233 kd->min_uva = VM_MIN_ADDRESS; 234 kd->max_uva = VM_MAXUSER_ADDRESS; 235 236 return 0; 237 } 238