lib/libkvm/kvm_x86_64.c

   1 /*-
   2  * Copyright (c) 1989, 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software developed by the Computer Systems
   6  * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
   7  * BG 91-66 and contributed to Berkeley.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed by the University of
  20  *      California, Berkeley and its contributors.
  21  * 4. Neither the name of the University nor the names of its contributors
  22  *    may be used to endorse or promote products derived from this software
  23  *    without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  35  * SUCH DAMAGE.
  36  *
  37  * @(#)kvm_hp300.c      8.1 (Berkeley) 6/4/93
  38  * $FreeBSD: src/lib/libkvm/kvm_amd64.c,v 1.16 2003/04/30 21:05:33 peter Exp $
  39  */
  40
  41 /*
  42  * x86_64 machine dependent routines for kvm.  Hopefully, the forthcoming
  43  * vm code will one day obsolete this module.
  44  */
  45
  46 #include <sys/user.h>   /* MUST BE FIRST */
  47 #include <sys/param.h>
  48 #include <sys/proc.h>
  49 #include <sys/stat.h>
  50 #include <stdlib.h>
  51 #include <unistd.h>
  52 #include <nlist.h>
  53 #include <kvm.h>
  54
  55 #include <vm/vm.h>
  56 #include <vm/vm_param.h>
  57
  58 #include <limits.h>
  59
  60 #include "kvm_private.h"
  61
  62 #ifndef btop
  63 #define btop(x)         (x86_64_btop(x))
  64 #define ptob(x)         (x86_64_ptob(x))
  65 #endif
  66
  67 struct vmstate {
  68         pml4_entry_t    *PML4;
  69 };
  70
  71 void
  72 _kvm_freevtop(kvm_t *kd)
  73 {
  74         if (kd->vmst != 0) {
  75                 if (kd->vmst->PML4) {
  76                         free(kd->vmst->PML4);
  77                 }
  78                 free(kd->vmst);
  79         }
  80 }
  81
  82 int
  83 _kvm_initvtop(kvm_t *kd)
  84 {
  85         struct vmstate *vm;
  86         struct nlist nlist[2];
  87         u_long pa;
  88         u_long kernbase;
  89         pml4_entry_t    *PML4;
  90
  91         vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm));
  92         if (vm == 0) {
  93                 _kvm_err(kd, kd->program, "cannot allocate vm");
  94                 return (-1);
  95         }
  96         kd->vmst = vm;
  97         vm->PML4 = 0;
  98
  99         nlist[0].n_name = "kernbase";
 100         nlist[1].n_name = 0;
 101
 102         if (kvm_nlist(kd, nlist) != 0) {
 103                 _kvm_err(kd, kd->program, "bad namelist - no kernbase");
 104                 return (-1);
 105         }
 106         kernbase = nlist[0].n_value;
 107
 108         nlist[0].n_name = "KPML4phys";
 109         nlist[1].n_name = 0;
 110
 111         if (kvm_nlist(kd, nlist) != 0) {
 112                 _kvm_err(kd, kd->program, "bad namelist - no KPML4phys");
 113                 return (-1);
 114         }
 115         if (kvm_read(kd, (nlist[0].n_value - kernbase), &pa, sizeof(pa)) !=
 116             sizeof(pa)) {
 117                 _kvm_err(kd, kd->program, "cannot read KPML4phys");
 118                 return (-1);
 119         }
 120         PML4 = _kvm_malloc(kd, PAGE_SIZE);
 121         if (kvm_read(kd, pa, PML4, PAGE_SIZE) != PAGE_SIZE) {
 122                 _kvm_err(kd, kd->program, "cannot read KPML4phys");
 123                 return (-1);
 124         }
 125         vm->PML4 = PML4;
 126         return (0);
 127 }
 128
 129 static int
 130 _kvm_vatop(kvm_t *kd, u_long va, u_long *pa)
 131 {
 132         struct vmstate *vm;
 133         u_long offset;
 134         u_long pdpe_pa;
 135         u_long pde_pa;
 136         u_long pte_pa;
 137         pml4_entry_t pml4e;
 138         pdp_entry_t pdpe;
 139         pd_entry_t pde;
 140         pt_entry_t pte;
 141         u_long pml4eindex;
 142         u_long pdpeindex;
 143         u_long pdeindex;
 144         u_long pteindex;
 145
 146         if (kvm_ishost(kd)) {
 147                 _kvm_err(kd, 0, "kvm_vatop called in live kernel!");
 148                 return((off_t)0);
 149         }
 150
 151         vm = kd->vmst;
 152         offset = va & (PAGE_SIZE - 1);
 153
 154         /*
 155          * If we are initializing (kernel page table descriptor pointer
 156          * not yet set) then return pa == va to avoid infinite recursion.
 157          */
 158         if (vm->PML4 == 0) {
 159                 *pa = va;
 160                 return (PAGE_SIZE - offset);
 161         }
 162
 163         pml4eindex = (va >> PML4SHIFT) & (NPML4EPG - 1);
 164         pml4e = vm->PML4[pml4eindex];
 165         if (((u_long)pml4e & PG_V) == 0)
 166                 goto invalid;
 167
 168         pdpeindex = (va >> PDPSHIFT) & (NPDPEPG-1);
 169         pdpe_pa = ((u_long)pml4e & PG_FRAME) + (pdpeindex * sizeof(pdp_entry_t));
 170
 171         /* XXX This has to be a physical address read, kvm_read is virtual */
 172         if (lseek(kd->pmfd, pdpe_pa, 0) == -1) {
 173                 _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pdpe_pa");
 174                 goto invalid;
 175         }
 176         if (read(kd->pmfd, &pdpe, sizeof pdpe) != sizeof pdpe) {
 177                 _kvm_syserr(kd, kd->program, "_kvm_vatop: read pdpe");
 178                 goto invalid;
 179         }
 180         if (((u_long)pdpe & PG_V) == 0)
 181                 goto invalid;
 182
 183
 184         pdeindex = (va >> PDRSHIFT) & (NPDEPG-1);
 185         pde_pa = ((u_long)pdpe & PG_FRAME) + (pdeindex * sizeof(pd_entry_t));
 186
 187         /* XXX This has to be a physical address read, kvm_read is virtual */
 188         if (lseek(kd->pmfd, pde_pa, 0) == -1) {
 189                 _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pde_pa");
 190                 goto invalid;
 191         }
 192         if (read(kd->pmfd, &pde, sizeof pde) != sizeof pde) {
 193                 _kvm_syserr(kd, kd->program, "_kvm_vatop: read pde");
 194                 goto invalid;
 195         }
 196         if (((u_long)pde & PG_V) == 0)
 197                 goto invalid;
 198
 199         if ((u_long)pde & PG_PS) {
 200               /*
 201                * No final-level page table; ptd describes one 2MB page.
 202                */
 203 #define PAGE2M_MASK     (NBPDR - 1)
 204 #define PG_FRAME2M      (~PAGE2M_MASK)
 205                 *pa = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK);
 206                 return (NBPDR - (va & PAGE2M_MASK));
 207         }
 208
 209         pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1);
 210         pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pt_entry_t));
 211
 212         /* XXX This has to be a physical address read, kvm_read is virtual */
 213         if (lseek(kd->pmfd, pte_pa, 0) == -1) {
 214                 _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek");
 215                 goto invalid;
 216         }
 217         if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) {
 218                 _kvm_syserr(kd, kd->program, "_kvm_vatop: read");
 219                 goto invalid;
 220         }
 221         if (((u_long)pte & PG_V) == 0)
 222                 goto invalid;
 223
 224         *pa = ((u_long)pte & PG_FRAME) + offset;
 225         return (PAGE_SIZE - offset);
 226
 227 invalid:
 228         _kvm_err(kd, 0, "invalid address (%jx)", (intmax_t)va);
 229         return (0);
 230 }
 231
 232 int
 233 _kvm_kvatop(kvm_t *kd, u_long va, u_long *pa)
 234 {
 235         return (_kvm_vatop(kd, va, pa));
 236 }