lib/libkvm/kvm_i386.c

   1 /*      $NetBSD: kvm_i386.c,v 1.24 2008/01/05 06:54:12 jld 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 1.24 2008/01/05 06:54:12 jld 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 <machine/kcore.h>
  54 #include <stdlib.h>
  55 #include <unistd.h>
  56 #include <nlist.h>
  57 #include <kvm.h>
  58
  59 #include <uvm/uvm_extern.h>
  60
  61 #include <limits.h>
  62 #include <db.h>
  63
  64 #include "kvm_private.h"
  65
  66 #include <machine/pmap.h>
  67 #include <machine/pte.h>
  68 #include <machine/vmparam.h>
  69
  70 #ifndef btop
  71 #define btop(x)         (((unsigned)(x)) >> PGSHIFT)    /* XXX */
  72 #define ptob(x)         ((caddr_t)((x) << PGSHIFT))     /* XXX */
  73 #endif
  74
  75 void
  76 _kvm_freevtop(kd)
  77         kvm_t *kd;
  78 {
  79
  80         /* Not actually used for anything right now, but safe. */
  81         if (kd->vmst != 0)
  82                 free(kd->vmst);
  83 }
  84
  85 /*ARGSUSED*/
  86 int
  87 _kvm_initvtop(kd)
  88         kvm_t *kd;
  89 {
  90
  91         return (0);
  92 }
  93
  94 /*
  95  * Translate a kernel virtual address to a physical address.
  96  */
  97 int
  98 _kvm_kvatop(kd, va, pa)
  99         kvm_t *kd;
 100         u_long va;
 101         u_long *pa;
 102 {
 103         cpu_kcore_hdr_t *cpu_kh;
 104         u_long page_off;
 105         pd_entry_t pde;
 106         pt_entry_t pte;
 107         u_long pde_pa, pte_pa;
 108
 109         if (ISALIVE(kd)) {
 110                 _kvm_err(kd, 0, "vatop called in live kernel!");
 111                 return (0);
 112         }
 113
 114         cpu_kh = kd->cpu_data;
 115         page_off = va & PGOFSET;
 116
 117         /*
 118          * Find and read the page directory entry.
 119          */
 120         pde_pa = cpu_kh->pdppaddr + (pl2_pi(va) * sizeof(pd_entry_t));
 121         if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
 122             _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
 123                 _kvm_syserr(kd, 0, "could not read PDE");
 124                 goto lose;
 125         }
 126
 127         /*
 128          * Find and read the page table entry.
 129          */
 130         if ((pde & PG_V) == 0) {
 131                 _kvm_err(kd, 0, "invalid translation (invalid PDE)");
 132                 goto lose;
 133         }
 134         if ((pde & PG_PS) != 0) {
 135                 /*
 136                  * This is a 4MB page.
 137                  */
 138                 page_off = va & ~PG_LGFRAME;
 139                 *pa = (pde & PG_LGFRAME) + page_off;
 140                 return (int)(NBPD_L2 - page_off);
 141         }
 142         pte_pa = (pde & PG_FRAME) + (pl1_pi(va) * sizeof(pt_entry_t));
 143         if (_kvm_pread(kd, kd->pmfd, (void *) &pte, sizeof(pte),
 144             _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
 145                 _kvm_syserr(kd, 0, "could not read PTE");
 146                 goto lose;
 147         }
 148
 149         /*
 150          * Validate the PTE and return the physical address.
 151          */
 152         if ((pte & PG_V) == 0) {
 153                 _kvm_err(kd, 0, "invalid translation (invalid PTE)");
 154                 goto lose;
 155         }
 156         *pa = (pte & PG_FRAME) + page_off;
 157         return (int)(NBPG - page_off);
 158
 159  lose:
 160         *pa = (u_long)~0L;
 161         return (0);
 162 }
 163
 164 /*
 165  * Translate a physical address to a file-offset in the crash dump.
 166  */
 167 off_t
 168 _kvm_pa2off(kd, pa)
 169         kvm_t *kd;
 170         u_long pa;
 171 {
 172         cpu_kcore_hdr_t *cpu_kh;
 173         phys_ram_seg_t *ramsegs;
 174         off_t off;
 175         int i;
 176
 177         cpu_kh = kd->cpu_data;
 178         ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh));
 179
 180         off = 0;
 181         for (i = 0; i < cpu_kh->nmemsegs; i++) {
 182                 if (pa >= ramsegs[i].start &&
 183                     (pa - ramsegs[i].start) < ramsegs[i].size) {
 184                         off += (pa - ramsegs[i].start);
 185                         break;
 186                 }
 187                 off += ramsegs[i].size;
 188         }
 189
 190         return (kd->dump_off + off);
 191 }
 192
 193 /*
 194  * Machine-dependent initialization for ALL open kvm descriptors,
 195  * not just those for a kernel crash dump.  Some architectures
 196  * have to deal with these NOT being constants!  (i.e. m68k)
 197  */
 198 int
 199 _kvm_mdopen(kd)
 200         kvm_t   *kd;
 201 {
 202
 203         kd->usrstack = USRSTACK;
 204         kd->min_uva = VM_MIN_ADDRESS;
 205         kd->max_uva = VM_MAXUSER_ADDRESS;
 206
 207         return (0);
 208 }