1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2006 Peter Wemm 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 /* 32 * i386 machine dependent routines for kvm and minidumps. 33 */ 34 35 #include <sys/param.h> 36 #include <sys/endian.h> 37 #include <stdint.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <unistd.h> 41 #include <vm/vm.h> 42 #include <kvm.h> 43 44 #include "../../sys/i386/include/minidump.h" 45 46 #include <limits.h> 47 48 #include "kvm_private.h" 49 #include "kvm_i386.h" 50 51 #define i386_round_page(x) roundup2((kvaddr_t)(x), I386_PAGE_SIZE) 52 53 struct vmstate { 54 struct minidumphdr hdr; 55 }; 56 57 static i386_pte_pae_t 58 _i386_pte_pae_get(kvm_t *kd, u_long pteindex) 59 { 60 i386_pte_pae_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte)); 61 62 return le64toh(*pte); 63 } 64 65 static i386_pte_t 66 _i386_pte_get(kvm_t *kd, u_long pteindex) 67 { 68 i386_pte_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte)); 69 70 return le32toh(*pte); 71 } 72 73 static int 74 _i386_minidump_probe(kvm_t *kd) 75 { 76 77 return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_386) && 78 _kvm_is_minidump(kd)); 79 } 80 81 static void 82 _i386_minidump_freevtop(kvm_t *kd) 83 { 84 struct vmstate *vm = kd->vmst; 85 86 free(vm); 87 kd->vmst = NULL; 88 } 89 90 static int 91 _i386_minidump_initvtop(kvm_t *kd) 92 { 93 struct vmstate *vmst; 94 off_t off, dump_avail_off, sparse_off; 95 96 vmst = _kvm_malloc(kd, sizeof(*vmst)); 97 if (vmst == NULL) { 98 _kvm_err(kd, kd->program, "cannot allocate vm"); 99 return (-1); 100 } 101 kd->vmst = vmst; 102 if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) != 103 sizeof(vmst->hdr)) { 104 _kvm_err(kd, kd->program, "cannot read dump header"); 105 return (-1); 106 } 107 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) { 108 _kvm_err(kd, kd->program, "not a minidump for this platform"); 109 return (-1); 110 } 111 vmst->hdr.version = le32toh(vmst->hdr.version); 112 if (vmst->hdr.version != MINIDUMP_VERSION && vmst->hdr.version != 1) { 113 _kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d", 114 MINIDUMP_VERSION, vmst->hdr.version); 115 return (-1); 116 } 117 vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize); 118 vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize); 119 vmst->hdr.ptesize = le32toh(vmst->hdr.ptesize); 120 vmst->hdr.kernbase = le32toh(vmst->hdr.kernbase); 121 vmst->hdr.paemode = le32toh(vmst->hdr.paemode); 122 vmst->hdr.dumpavailsize = vmst->hdr.version == MINIDUMP_VERSION ? 123 le32toh(vmst->hdr.dumpavailsize) : 0; 124 125 /* Skip header and msgbuf */ 126 dump_avail_off = I386_PAGE_SIZE + i386_round_page(vmst->hdr.msgbufsize); 127 128 /* Skip dump_avail */ 129 off = dump_avail_off + i386_round_page(vmst->hdr.dumpavailsize); 130 131 sparse_off = off + i386_round_page(vmst->hdr.bitmapsize) + 132 i386_round_page(vmst->hdr.ptesize); 133 if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off, 134 vmst->hdr.bitmapsize, off, sparse_off, I386_PAGE_SIZE, 135 sizeof(uint32_t)) == -1) { 136 return (-1); 137 } 138 off += i386_round_page(vmst->hdr.bitmapsize); 139 140 if (_kvm_pmap_init(kd, vmst->hdr.ptesize, off) == -1) { 141 return (-1); 142 } 143 off += i386_round_page(vmst->hdr.ptesize); 144 145 return (0); 146 } 147 148 static int 149 _i386_minidump_vatop_pae(kvm_t *kd, kvaddr_t va, off_t *pa) 150 { 151 struct vmstate *vm; 152 i386_physaddr_pae_t offset; 153 i386_pte_pae_t pte; 154 kvaddr_t pteindex; 155 i386_physaddr_pae_t a; 156 off_t ofs; 157 158 vm = kd->vmst; 159 offset = va & I386_PAGE_MASK; 160 161 if (va >= vm->hdr.kernbase) { 162 pteindex = (va - vm->hdr.kernbase) >> I386_PAGE_SHIFT; 163 if (pteindex >= vm->hdr.ptesize / sizeof(pte)) 164 goto invalid; 165 pte = _i386_pte_pae_get(kd, pteindex); 166 if ((pte & I386_PG_V) == 0) { 167 _kvm_err(kd, kd->program, 168 "_i386_minidump_vatop_pae: pte not valid"); 169 goto invalid; 170 } 171 a = pte & I386_PG_FRAME_PAE; 172 ofs = _kvm_pt_find(kd, a, I386_PAGE_SIZE); 173 if (ofs == -1) { 174 _kvm_err(kd, kd->program, 175 "_i386_minidump_vatop_pae: physical address 0x%jx not in minidump", 176 (uintmax_t)a); 177 goto invalid; 178 } 179 *pa = ofs + offset; 180 return (I386_PAGE_SIZE - offset); 181 } else { 182 _kvm_err(kd, kd->program, 183 "_i386_minidump_vatop_pae: virtual address 0x%jx not minidumped", 184 (uintmax_t)va); 185 goto invalid; 186 } 187 188 invalid: 189 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va); 190 return (0); 191 } 192 193 static int 194 _i386_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa) 195 { 196 struct vmstate *vm; 197 i386_physaddr_t offset; 198 i386_pte_t pte; 199 kvaddr_t pteindex; 200 i386_physaddr_t a; 201 off_t ofs; 202 203 vm = kd->vmst; 204 offset = va & I386_PAGE_MASK; 205 206 if (va >= vm->hdr.kernbase) { 207 pteindex = (va - vm->hdr.kernbase) >> I386_PAGE_SHIFT; 208 if (pteindex >= vm->hdr.ptesize / sizeof(pte)) 209 goto invalid; 210 pte = _i386_pte_get(kd, pteindex); 211 if ((pte & I386_PG_V) == 0) { 212 _kvm_err(kd, kd->program, 213 "_i386_minidump_vatop: pte not valid"); 214 goto invalid; 215 } 216 a = pte & I386_PG_FRAME; 217 ofs = _kvm_pt_find(kd, a, I386_PAGE_SIZE); 218 if (ofs == -1) { 219 _kvm_err(kd, kd->program, 220 "_i386_minidump_vatop: physical address 0x%jx not in minidump", 221 (uintmax_t)a); 222 goto invalid; 223 } 224 *pa = ofs + offset; 225 return (I386_PAGE_SIZE - offset); 226 } else { 227 _kvm_err(kd, kd->program, 228 "_i386_minidump_vatop: virtual address 0x%jx not minidumped", 229 (uintmax_t)va); 230 goto invalid; 231 } 232 233 invalid: 234 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va); 235 return (0); 236 } 237 238 static int 239 _i386_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa) 240 { 241 242 if (ISALIVE(kd)) { 243 _kvm_err(kd, 0, "_i386_minidump_kvatop called in live kernel!"); 244 return (0); 245 } 246 if (kd->vmst->hdr.paemode) 247 return (_i386_minidump_vatop_pae(kd, va, pa)); 248 else 249 return (_i386_minidump_vatop(kd, va, pa)); 250 } 251 252 static vm_prot_t 253 _i386_entry_to_prot(uint64_t pte) 254 { 255 vm_prot_t prot = VM_PROT_READ; 256 257 /* Source: i386/pmap.c:pmap_protect() */ 258 if (pte & I386_PG_RW) 259 prot |= VM_PROT_WRITE; 260 if ((pte & I386_PG_NX) == 0) 261 prot |= VM_PROT_EXECUTE; 262 263 return prot; 264 } 265 266 struct i386_iter { 267 kvm_t *kd; 268 u_long nptes; 269 u_long pteindex; 270 }; 271 272 static void 273 _i386_iterator_init(struct i386_iter *it, kvm_t *kd) 274 { 275 struct vmstate *vm = kd->vmst; 276 277 it->kd = kd; 278 it->pteindex = 0; 279 if (vm->hdr.paemode) { 280 it->nptes = vm->hdr.ptesize / sizeof(i386_pte_pae_t); 281 } else { 282 it->nptes = vm->hdr.ptesize / sizeof(i386_pte_t); 283 } 284 return; 285 } 286 287 static int 288 _i386_iterator_next(struct i386_iter *it, u_long *pa, u_long *va, u_long *dva, 289 vm_prot_t *prot) 290 { 291 struct vmstate *vm = it->kd->vmst; 292 i386_pte_t pte32; 293 i386_pte_pae_t pte64; 294 int found = 0; 295 296 *dva = 0; 297 *pa = 0; 298 *va = 0; 299 *dva = 0; 300 *prot = 0; 301 for (; it->pteindex < it->nptes && found == 0; it->pteindex++) { 302 if (vm->hdr.paemode) { 303 pte64 = _i386_pte_pae_get(it->kd, it->pteindex); 304 if ((pte64 & I386_PG_V) == 0) 305 continue; 306 *prot = _i386_entry_to_prot(pte64); 307 *pa = pte64 & I386_PG_FRAME_PAE; 308 } else { 309 pte32 = _i386_pte_get(it->kd, it->pteindex); 310 if ((pte32 & I386_PG_V) == 0) 311 continue; 312 *prot = _i386_entry_to_prot(pte32); 313 *pa = pte32 & I386_PG_FRAME; 314 } 315 *va = vm->hdr.kernbase + (it->pteindex << I386_PAGE_SHIFT); 316 found = 1; 317 } 318 return found; 319 } 320 321 static int 322 _i386_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg) 323 { 324 struct i386_iter it; 325 u_long dva, pa, va; 326 vm_prot_t prot; 327 328 _i386_iterator_init(&it, kd); 329 while (_i386_iterator_next(&it, &pa, &va, &dva, &prot)) { 330 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva, 331 prot, I386_PAGE_SIZE, 0)) { 332 return (0); 333 } 334 } 335 return (1); 336 } 337 338 static struct kvm_arch kvm_i386_minidump = { 339 .ka_probe = _i386_minidump_probe, 340 .ka_initvtop = _i386_minidump_initvtop, 341 .ka_freevtop = _i386_minidump_freevtop, 342 .ka_kvatop = _i386_minidump_kvatop, 343 .ka_native = _i386_native, 344 .ka_walk_pages = _i386_minidump_walk_pages, 345 }; 346 347 KVM_ARCH(kvm_i386_minidump); 348