lib/libkvm/kvm_minidump_mips.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2010 Oleksandr Tymoshenko
   5  * Copyright (c) 2008 Semihalf, Grzegorz Bernacki
   6  * Copyright (c) 2006 Peter Wemm
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * From: FreeBSD: src/lib/libkvm/kvm_minidump_arm.c r214223
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __FBSDID("$FreeBSD$");
  34
  35 /*
  36  * MIPS machine dependent routines for kvm and minidumps.
  37  */
  38
  39 #include <sys/param.h>
  40 #include <vm/vm.h>
  41 #include <kvm.h>
  42 #include <limits.h>
  43 #include <stdint.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46 #include <unistd.h>
  47
  48 #include "../../sys/mips/include/cpuregs.h"
  49 #include "../../sys/mips/include/minidump.h"
  50
  51 #include "kvm_private.h"
  52 #include "kvm_mips.h"
  53
  54 #define mips_round_page(x)      roundup2((kvaddr_t)(x), MIPS_PAGE_SIZE)
  55
  56 struct vmstate {
  57         struct          minidumphdr hdr;
  58         int             pte_size;
  59 };
  60
  61 static int
  62 _mips_minidump_probe(kvm_t *kd)
  63 {
  64
  65         if (kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS32 &&
  66             kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS64)
  67                 return (0);
  68         if (kd->nlehdr.e_machine != EM_MIPS)
  69                 return (0);
  70         return (_kvm_is_minidump(kd));
  71 }
  72
  73 static void
  74 _mips_minidump_freevtop(kvm_t *kd)
  75 {
  76         struct vmstate *vm = kd->vmst;
  77
  78         free(vm);
  79         kd->vmst = NULL;
  80 }
  81
  82 static int
  83 _mips_minidump_initvtop(kvm_t *kd)
  84 {
  85         struct vmstate *vmst;
  86         off_t off, sparse_off;
  87
  88         vmst = _kvm_malloc(kd, sizeof(*vmst));
  89         if (vmst == NULL) {
  90                 _kvm_err(kd, kd->program, "cannot allocate vm");
  91                 return (-1);
  92         }
  93
  94         kd->vmst = vmst;
  95
  96         if (kd->nlehdr.e_ident[EI_CLASS] == ELFCLASS64 ||
  97             kd->nlehdr.e_flags & EF_MIPS_ABI2)
  98                 vmst->pte_size = 64;
  99         else
 100                 vmst->pte_size = 32;
 101
 102         if (pread(kd->pmfd, &vmst->hdr,
 103             sizeof(vmst->hdr), 0) != sizeof(vmst->hdr)) {
 104                 _kvm_err(kd, kd->program, "cannot read dump header");
 105                 return (-1);
 106         }
 107
 108         if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
 109             sizeof(vmst->hdr.magic)) != 0) {
 110                 _kvm_err(kd, kd->program, "not a minidump for this platform");
 111                 return (-1);
 112         }
 113         vmst->hdr.version = _kvm32toh(kd, vmst->hdr.version);
 114         if (vmst->hdr.version != MINIDUMP_VERSION) {
 115                 _kvm_err(kd, kd->program, "wrong minidump version. "
 116                     "Expected %d got %d", MINIDUMP_VERSION, vmst->hdr.version);
 117                 return (-1);
 118         }
 119         vmst->hdr.msgbufsize = _kvm32toh(kd, vmst->hdr.msgbufsize);
 120         vmst->hdr.bitmapsize = _kvm32toh(kd, vmst->hdr.bitmapsize);
 121         vmst->hdr.ptesize = _kvm32toh(kd, vmst->hdr.ptesize);
 122         vmst->hdr.kernbase = _kvm64toh(kd, vmst->hdr.kernbase);
 123         vmst->hdr.dmapbase = _kvm64toh(kd, vmst->hdr.dmapbase);
 124         vmst->hdr.dmapend = _kvm64toh(kd, vmst->hdr.dmapend);
 125
 126         /* Skip header and msgbuf */
 127         off = MIPS_PAGE_SIZE + mips_round_page(vmst->hdr.msgbufsize);
 128
 129         sparse_off = off + mips_round_page(vmst->hdr.bitmapsize) +
 130             mips_round_page(vmst->hdr.ptesize);
 131         if (_kvm_pt_init(kd, vmst->hdr.bitmapsize, off, sparse_off,
 132             MIPS_PAGE_SIZE, sizeof(uint32_t)) == -1) {
 133                 return (-1);
 134         }
 135         off += mips_round_page(vmst->hdr.bitmapsize);
 136
 137         if (_kvm_pmap_init(kd, vmst->hdr.ptesize, off) == -1) {
 138                 return (-1);
 139         }
 140         off += mips_round_page(vmst->hdr.ptesize);
 141
 142         return (0);
 143 }
 144
 145 static int
 146 _mips_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
 147 {
 148         struct vmstate *vm;
 149         mips_physaddr_t offset, a;
 150         kvaddr_t pteindex;
 151         u_long valid;
 152         off_t ofs;
 153         mips32_pte_t pte32;
 154         mips64_pte_t pte64;
 155
 156         if (ISALIVE(kd)) {
 157                 _kvm_err(kd, 0, "_mips_minidump_kvatop called in live kernel!");
 158                 return (0);
 159         }
 160
 161         offset = va & MIPS_PAGE_MASK;
 162         /* Operate with page-aligned address */
 163         va &= ~MIPS_PAGE_MASK;
 164
 165         vm = kd->vmst;
 166         if (kd->nlehdr.e_ident[EI_CLASS] == ELFCLASS64) {
 167                 if (va >= MIPS_XKPHYS_START && va < MIPS_XKPHYS_END) {
 168                         a = va & MIPS_XKPHYS_PHYS_MASK;
 169                         goto found;
 170                 }
 171                 if (va >= MIPS64_KSEG0_START && va < MIPS64_KSEG0_END) {
 172                         a = va & MIPS_KSEG0_PHYS_MASK;
 173                         goto found;
 174                 }
 175                 if (va >= MIPS64_KSEG1_START && va < MIPS64_KSEG1_END) {
 176                         a = va & MIPS_KSEG0_PHYS_MASK;
 177                         goto found;
 178                 }
 179         } else {
 180                 if (va >= MIPS32_KSEG0_START && va < MIPS32_KSEG0_END) {
 181                         a = va & MIPS_KSEG0_PHYS_MASK;
 182                         goto found;
 183                 }
 184                 if (va >= MIPS32_KSEG1_START && va < MIPS32_KSEG1_END) {
 185                         a = va & MIPS_KSEG0_PHYS_MASK;
 186                         goto found;
 187                 }
 188         }
 189         if (va >= vm->hdr.kernbase) {
 190                 pteindex = (va - vm->hdr.kernbase) >> MIPS_PAGE_SHIFT;
 191                 if (vm->pte_size == 64) {
 192                         valid = pteindex < vm->hdr.ptesize / sizeof(pte64);
 193                         if (pteindex >= vm->hdr.ptesize / sizeof(pte64))
 194                                 goto invalid;
 195                         pte64 = _mips64_pte_get(kd, pteindex);
 196                         valid = pte64 & MIPS_PTE_V;
 197                         if (valid)
 198                                 a = MIPS64_PTE_TO_PA(pte64);
 199                 } else {
 200                         if (pteindex >= vm->hdr.ptesize / sizeof(pte32))
 201                                 goto invalid;
 202                         pte32 = _mips32_pte_get(kd, pteindex);
 203                         valid = pte32 & MIPS_PTE_V;
 204                         if (valid)
 205                                 a = MIPS32_PTE_TO_PA(pte32);
 206                 }
 207                 if (!valid) {
 208                         _kvm_err(kd, kd->program, "_mips_minidump_kvatop: pte "
 209                             "not valid");
 210                         goto invalid;
 211                 }
 212         } else {
 213                 _kvm_err(kd, kd->program, "_mips_minidump_kvatop: virtual "
 214                     "address 0x%jx not minidumped", (uintmax_t)va);
 215                 return (0);
 216         }
 217
 218 found:
 219         ofs = _kvm_pt_find(kd, a, MIPS_PAGE_SIZE);
 220         if (ofs == -1) {
 221                 _kvm_err(kd, kd->program, "_mips_minidump_kvatop: physical "
 222                     "address 0x%jx not in minidump", (uintmax_t)a);
 223                 goto invalid;
 224         }
 225
 226         *pa = ofs + offset;
 227         return (MIPS_PAGE_SIZE - offset);
 228
 229
 230 invalid:
 231         _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
 232         return (0);
 233 }
 234
 235 static int
 236 #ifdef __mips__
 237 _mips_native(kvm_t *kd)
 238 #else
 239 _mips_native(kvm_t *kd __unused)
 240 #endif
 241 {
 242
 243 #ifdef __mips__
 244 #ifdef __mips_n64
 245         if (kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS64)
 246                 return (0);
 247 #else
 248         if (kd->nlehdr.e_ident[EI_CLASS] != ELFCLASS32)
 249                 return (0);
 250 #ifdef __mips_n32
 251         if (!(kd->nlehdr.e_flags & EF_MIPS_ABI2))
 252                 return (0);
 253 #else
 254         if (kd->nlehdr.e_flags & EF_MIPS_ABI2)
 255                 return (0);
 256 #endif
 257 #endif
 258 #if _BYTE_ORDER == _LITTLE_ENDIAN
 259         return (kd->nlehdr.e_ident[EI_DATA] == ELFDATA2LSB);
 260 #else
 261         return (kd->nlehdr.e_ident[EI_DATA] == ELFDATA2MSB);
 262 #endif
 263 #else
 264         return (0);
 265 #endif
 266 }
 267
 268 struct mips_iter {
 269         kvm_t *kd;
 270         u_long nptes;
 271         u_long pteindex;
 272 };
 273
 274 static void
 275 _mips_iterator_init(struct mips_iter *it, kvm_t *kd)
 276 {
 277         struct vmstate *vm = kd->vmst;
 278
 279         it->kd = kd;
 280         it->pteindex = 0;
 281         if (vm->pte_size == 64)
 282                 it->nptes = vm->hdr.ptesize / sizeof(mips64_pte_t);
 283         else
 284                 it->nptes = vm->hdr.ptesize / sizeof(mips32_pte_t);
 285         return;
 286 }
 287
 288 static int
 289 _mips_iterator_next(struct mips_iter *it, u_long *pa, u_long *va, u_long *dva,
 290     vm_prot_t *prot)
 291 {
 292         struct vmstate *vm = it->kd->vmst;
 293         int found = 0;
 294         mips64_pte_t pte64;
 295         mips32_pte_t pte32;
 296
 297         /*
 298          * mips/mips/pmap.c: init_pte_prot / pmap_protect indicate that all
 299          * pages are R|X at least.
 300          */
 301         *prot = VM_PROT_READ | VM_PROT_EXECUTE;
 302         *pa = 0;
 303         *va = 0;
 304         *dva = 0;
 305         for (;it->pteindex < it->nptes && found == 0; it->pteindex++) {
 306                 if (vm->pte_size == 64) {
 307                         pte64 = _mips64_pte_get(it->kd, it->pteindex);
 308                         if ((pte64 & MIPS_PTE_V) == 0)
 309                                 continue;
 310                         if ((pte64 & MIPS64_PTE_RO) == 0)
 311                                 *prot |= VM_PROT_WRITE;
 312                         *pa = MIPS64_PTE_TO_PA(pte64);
 313                 } else {
 314                         pte32 = _mips32_pte_get(it->kd, it->pteindex);
 315                         if ((pte32 & MIPS_PTE_V) == 0)
 316                                 continue;
 317                         if ((pte32 & MIPS32_PTE_RO) == 0)
 318                                 *prot |= VM_PROT_WRITE;
 319                         *pa = MIPS32_PTE_TO_PA(pte32);
 320                 }
 321                 *va = vm->hdr.kernbase + (it->pteindex << MIPS_PAGE_SHIFT);
 322                 found = 1;
 323                 /* advance pteindex regardless */
 324         }
 325
 326         return found;
 327 }
 328
 329 static int
 330 _mips_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg)
 331 {
 332         struct mips_iter it;
 333         u_long dva, pa, va;
 334         vm_prot_t prot;
 335
 336         /* Generate direct mapped entries; need page entries for prot etc? */
 337         if (kd->nlehdr.e_ident[EI_CLASS] == ELFCLASS64) {
 338                 /* MIPS_XKPHYS_START..MIPS_XKPHYS_END */
 339                 /* MIPS64_KSEG0_START..MIPS64_KSEG0_END */
 340                 /* MIPS64_KSEG1_START..MIPS64_KSEG1_START */
 341         } else {
 342                 /* MIPS32_KSEG0_START..MIPS32_KSEG0_END */
 343                 /* MIPS32_KSEG1_START..MIPS32_KSEG1_END */
 344         }
 345
 346         _mips_iterator_init(&it, kd);
 347         while (_mips_iterator_next(&it, &pa, &va, &dva, &prot)) {
 348                 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
 349                     prot, MIPS_PAGE_SIZE, 0)) {
 350                         return (0);
 351                 }
 352         }
 353         return (1);
 354 }
 355
 356 static struct kvm_arch kvm_mips_minidump = {
 357         .ka_probe = _mips_minidump_probe,
 358         .ka_initvtop = _mips_minidump_initvtop,
 359         .ka_freevtop = _mips_minidump_freevtop,
 360         .ka_kvatop = _mips_minidump_kvatop,
 361         .ka_native = _mips_native,
 362         .ka_walk_pages = _mips_minidump_walk_pages,
 363 };
 364
 365 KVM_ARCH(kvm_mips_minidump);