lib/libkvm/kvm_minidump_amd64.c

   1 /*-
   2  * Copyright (c) 2006 Peter Wemm
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  */
  25
  26 #include <sys/cdefs.h>
  27 __FBSDID("$FreeBSD$");
  28
  29 /*
  30  * AMD64 machine dependent routines for kvm and minidumps.
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/endian.h>
  35 #include <stdint.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <unistd.h>
  39 #include <kvm.h>
  40
  41 #include "../../sys/amd64/include/minidump.h"
  42
  43 #include <limits.h>
  44
  45 #include "kvm_private.h"
  46 #include "kvm_amd64.h"
  47
  48 #define amd64_round_page(x)     roundup2((kvaddr_t)(x), AMD64_PAGE_SIZE)
  49
  50 struct vmstate {
  51         struct minidumphdr hdr;
  52         struct hpt hpt;
  53         amd64_pte_t *page_map;
  54 };
  55
  56 static int
  57 _amd64_minidump_probe(kvm_t *kd)
  58 {
  59
  60         return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_X86_64) &&
  61             _kvm_is_minidump(kd));
  62 }
  63
  64 static void
  65 _amd64_minidump_freevtop(kvm_t *kd)
  66 {
  67         struct vmstate *vm = kd->vmst;
  68
  69         _kvm_hpt_free(&vm->hpt);
  70         if (vm->page_map)
  71                 free(vm->page_map);
  72         free(vm);
  73         kd->vmst = NULL;
  74 }
  75
  76 static int
  77 _amd64_minidump_initvtop(kvm_t *kd)
  78 {
  79         struct vmstate *vmst;
  80         uint64_t *bitmap;
  81         off_t off;
  82
  83         vmst = _kvm_malloc(kd, sizeof(*vmst));
  84         if (vmst == NULL) {
  85                 _kvm_err(kd, kd->program, "cannot allocate vm");
  86                 return (-1);
  87         }
  88         kd->vmst = vmst;
  89         if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
  90             sizeof(vmst->hdr)) {
  91                 _kvm_err(kd, kd->program, "cannot read dump header");
  92                 return (-1);
  93         }
  94         if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) {
  95                 _kvm_err(kd, kd->program, "not a minidump for this platform");
  96                 return (-1);
  97         }
  98
  99         /*
 100          * NB: amd64 minidump header is binary compatible between version 1
 101          * and version 2; this may not be the case for the future versions.
 102          */
 103         vmst->hdr.version = le32toh(vmst->hdr.version);
 104         if (vmst->hdr.version != MINIDUMP_VERSION && vmst->hdr.version != 1) {
 105                 _kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d",
 106                     MINIDUMP_VERSION, vmst->hdr.version);
 107                 return (-1);
 108         }
 109         vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize);
 110         vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize);
 111         vmst->hdr.pmapsize = le32toh(vmst->hdr.pmapsize);
 112         vmst->hdr.kernbase = le64toh(vmst->hdr.kernbase);
 113         vmst->hdr.dmapbase = le64toh(vmst->hdr.dmapbase);
 114         vmst->hdr.dmapend = le64toh(vmst->hdr.dmapend);
 115
 116         /* Skip header and msgbuf */
 117         off = AMD64_PAGE_SIZE + amd64_round_page(vmst->hdr.msgbufsize);
 118
 119         bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize);
 120         if (bitmap == NULL) {
 121                 _kvm_err(kd, kd->program, "cannot allocate %d bytes for bitmap", vmst->hdr.bitmapsize);
 122                 return (-1);
 123         }
 124         if (pread(kd->pmfd, bitmap, vmst->hdr.bitmapsize, off) !=
 125             (ssize_t)vmst->hdr.bitmapsize) {
 126                 _kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap", vmst->hdr.bitmapsize);
 127                 free(bitmap);
 128                 return (-1);
 129         }
 130         off += amd64_round_page(vmst->hdr.bitmapsize);
 131
 132         vmst->page_map = _kvm_malloc(kd, vmst->hdr.pmapsize);
 133         if (vmst->page_map == NULL) {
 134                 _kvm_err(kd, kd->program, "cannot allocate %d bytes for page_map", vmst->hdr.pmapsize);
 135                 free(bitmap);
 136                 return (-1);
 137         }
 138         if (pread(kd->pmfd, vmst->page_map, vmst->hdr.pmapsize, off) !=
 139             (ssize_t)vmst->hdr.pmapsize) {
 140                 _kvm_err(kd, kd->program, "cannot read %d bytes for page_map", vmst->hdr.pmapsize);
 141                 free(bitmap);
 142                 return (-1);
 143         }
 144         off += vmst->hdr.pmapsize;
 145
 146         /* build physical address hash table for sparse pages */
 147         _kvm_hpt_init(kd, &vmst->hpt, bitmap, vmst->hdr.bitmapsize, off,
 148             AMD64_PAGE_SIZE, sizeof(*bitmap));
 149         free(bitmap);
 150
 151         return (0);
 152 }
 153
 154 static int
 155 _amd64_minidump_vatop_v1(kvm_t *kd, kvaddr_t va, off_t *pa)
 156 {
 157         struct vmstate *vm;
 158         amd64_physaddr_t offset;
 159         amd64_pte_t pte;
 160         kvaddr_t pteindex;
 161         amd64_physaddr_t a;
 162         off_t ofs;
 163
 164         vm = kd->vmst;
 165         offset = va & AMD64_PAGE_MASK;
 166
 167         if (va >= vm->hdr.kernbase) {
 168                 pteindex = (va - vm->hdr.kernbase) >> AMD64_PAGE_SHIFT;
 169                 if (pteindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
 170                         goto invalid;
 171                 pte = le64toh(vm->page_map[pteindex]);
 172                 if ((pte & AMD64_PG_V) == 0) {
 173                         _kvm_err(kd, kd->program,
 174                             "_amd64_minidump_vatop_v1: pte not valid");
 175                         goto invalid;
 176                 }
 177                 a = pte & AMD64_PG_FRAME;
 178                 ofs = _kvm_hpt_find(&vm->hpt, a);
 179                 if (ofs == -1) {
 180                         _kvm_err(kd, kd->program,
 181             "_amd64_minidump_vatop_v1: physical address 0x%jx not in minidump",
 182                             (uintmax_t)a);
 183                         goto invalid;
 184                 }
 185                 *pa = ofs + offset;
 186                 return (AMD64_PAGE_SIZE - offset);
 187         } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
 188                 a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
 189                 ofs = _kvm_hpt_find(&vm->hpt, a);
 190                 if (ofs == -1) {
 191                         _kvm_err(kd, kd->program,
 192     "_amd64_minidump_vatop_v1: direct map address 0x%jx not in minidump",
 193                             (uintmax_t)va);
 194                         goto invalid;
 195                 }
 196                 *pa = ofs + offset;
 197                 return (AMD64_PAGE_SIZE - offset);
 198         } else {
 199                 _kvm_err(kd, kd->program,
 200             "_amd64_minidump_vatop_v1: virtual address 0x%jx not minidumped",
 201                     (uintmax_t)va);
 202                 goto invalid;
 203         }
 204
 205 invalid:
 206         _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
 207         return (0);
 208 }
 209
 210 static int
 211 _amd64_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
 212 {
 213         amd64_pte_t pt[AMD64_NPTEPG];
 214         struct vmstate *vm;
 215         amd64_physaddr_t offset;
 216         amd64_pde_t pde;
 217         amd64_pte_t pte;
 218         kvaddr_t pteindex;
 219         kvaddr_t pdeindex;
 220         amd64_physaddr_t a;
 221         off_t ofs;
 222
 223         vm = kd->vmst;
 224         offset = va & AMD64_PAGE_MASK;
 225
 226         if (va >= vm->hdr.kernbase) {
 227                 pdeindex = (va - vm->hdr.kernbase) >> AMD64_PDRSHIFT;
 228                 if (pdeindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
 229                         goto invalid;
 230                 pde = le64toh(vm->page_map[pdeindex]);
 231                 if ((pde & AMD64_PG_V) == 0) {
 232                         _kvm_err(kd, kd->program,
 233                             "_amd64_minidump_vatop: pde not valid");
 234                         goto invalid;
 235                 }
 236                 if ((pde & AMD64_PG_PS) == 0) {
 237                         a = pde & AMD64_PG_FRAME;
 238                         ofs = _kvm_hpt_find(&vm->hpt, a);
 239                         if (ofs == -1) {
 240                                 _kvm_err(kd, kd->program,
 241             "_amd64_minidump_vatop: pt physical address 0x%jx not in minidump",
 242                                     (uintmax_t)a);
 243                                 goto invalid;
 244                         }
 245                         /* TODO: Just read the single PTE */
 246                         if (pread(kd->pmfd, &pt, AMD64_PAGE_SIZE, ofs) !=
 247                             AMD64_PAGE_SIZE) {
 248                                 _kvm_err(kd, kd->program,
 249                                     "cannot read %d bytes for page table",
 250                                     AMD64_PAGE_SIZE);
 251                                 return (-1);
 252                         }
 253                         pteindex = (va >> AMD64_PAGE_SHIFT) &
 254                             (AMD64_NPTEPG - 1);
 255                         pte = le64toh(pt[pteindex]);
 256                         if ((pte & AMD64_PG_V) == 0) {
 257                                 _kvm_err(kd, kd->program,
 258                                     "_amd64_minidump_vatop: pte not valid");
 259                                 goto invalid;
 260                         }
 261                         a = pte & AMD64_PG_FRAME;
 262                 } else {
 263                         a = pde & AMD64_PG_PS_FRAME;
 264                         a += (va & AMD64_PDRMASK) ^ offset;
 265                 }
 266                 ofs = _kvm_hpt_find(&vm->hpt, a);
 267                 if (ofs == -1) {
 268                         _kvm_err(kd, kd->program,
 269             "_amd64_minidump_vatop: physical address 0x%jx not in minidump",
 270                             (uintmax_t)a);
 271                         goto invalid;
 272                 }
 273                 *pa = ofs + offset;
 274                 return (AMD64_PAGE_SIZE - offset);
 275         } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
 276                 a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
 277                 ofs = _kvm_hpt_find(&vm->hpt, a);
 278                 if (ofs == -1) {
 279                         _kvm_err(kd, kd->program,
 280             "_amd64_minidump_vatop: direct map address 0x%jx not in minidump",
 281                             (uintmax_t)va);
 282                         goto invalid;
 283                 }
 284                 *pa = ofs + offset;
 285                 return (AMD64_PAGE_SIZE - offset);
 286         } else {
 287                 _kvm_err(kd, kd->program,
 288             "_amd64_minidump_vatop: virtual address 0x%jx not minidumped",
 289                     (uintmax_t)va);
 290                 goto invalid;
 291         }
 292
 293 invalid:
 294         _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
 295         return (0);
 296 }
 297
 298 static int
 299 _amd64_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
 300 {
 301
 302         if (ISALIVE(kd)) {
 303                 _kvm_err(kd, 0,
 304                     "_amd64_minidump_kvatop called in live kernel!");
 305                 return (0);
 306         }
 307         if (((struct vmstate *)kd->vmst)->hdr.version == 1)
 308                 return (_amd64_minidump_vatop_v1(kd, va, pa));
 309         else
 310                 return (_amd64_minidump_vatop(kd, va, pa));
 311 }
 312
 313 static struct kvm_arch kvm_amd64_minidump = {
 314         .ka_probe = _amd64_minidump_probe,
 315         .ka_initvtop = _amd64_minidump_initvtop,
 316         .ka_freevtop = _amd64_minidump_freevtop,
 317         .ka_kvatop = _amd64_minidump_kvatop,
 318         .ka_native = _amd64_native,
 319 };
 320
 321 KVM_ARCH(kvm_amd64_minidump);