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. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93 34 * $FreeBSD: src/lib/libkvm/kvm_amd64.c,v 1.16 2003/04/30 21:05:33 peter Exp $ 35 */ 36 37 /* 38 * x86_64 machine dependent routines for kvm. Hopefully, the forthcoming 39 * vm code will one day obsolete this module. 40 */ 41 42 #include <sys/user.h> /* MUST BE FIRST */ 43 #include <sys/param.h> 44 #include <sys/stat.h> 45 #include <sys/mman.h> 46 #include <sys/elf_common.h> 47 #include <stdlib.h> 48 #include <string.h> 49 #include <unistd.h> 50 #include <nlist.h> 51 52 #include <cpu/pmap.h> 53 #include <vm/vm.h> 54 #include <vm/vm_param.h> 55 56 #include <machine/elf.h> 57 58 #include <limits.h> 59 60 #include "kvm.h" 61 #include "kvm_private.h" 62 63 #ifndef btop 64 #define btop(x) (x86_64_btop(x)) 65 #define ptob(x) (x86_64_ptob(x)) 66 #endif 67 68 struct vmstate { 69 int minidump; /* 1 = minidump mode */ 70 void *mmapbase; 71 size_t mmapsize; 72 pml4_entry_t *PML4; 73 }; 74 75 /* 76 * Map the ELF headers into the process' address space. We do this in two 77 * steps: first the ELF header itself and using that information the whole 78 * set of headers. (Taken from kvm_ia64.c) 79 */ 80 static int 81 _kvm_maphdrs(kvm_t *kd, size_t sz) 82 { 83 struct vmstate *vm = kd->vmst; 84 85 if (kd->vmst->minidump) { 86 _kvm_minidump_freevtop(kd); 87 return (0); 88 } 89 90 /* munmap() previous mmap(). */ 91 if (vm->mmapbase != NULL) { 92 munmap(vm->mmapbase, vm->mmapsize); 93 vm->mmapbase = NULL; 94 } 95 96 vm->mmapsize = sz; 97 vm->mmapbase = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 98 if (vm->mmapbase == MAP_FAILED) { 99 _kvm_err(kd, kd->program, "cannot mmap corefile"); 100 return (-1); 101 } 102 return (0); 103 } 104 105 /* 106 * Translate a physical memory address to a file-offset in the crash-dump. 107 * (Taken from kvm_ia64.c) 108 */ 109 static size_t 110 _kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs) 111 { 112 Elf_Ehdr *e = kd->vmst->mmapbase; 113 Elf_Phdr *p; 114 int n; 115 116 if (kd->rawdump) { 117 *ofs = pa; 118 return (PAGE_SIZE - ((size_t)pa & PAGE_MASK)); 119 } 120 121 p = (Elf_Phdr*)((char*)e + e->e_phoff); 122 n = e->e_phnum; 123 124 while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz)) 125 p++, n--; 126 if (n == 0) 127 return (0); 128 *ofs = (pa - p->p_paddr) + p->p_offset; 129 return (PAGE_SIZE - ((size_t)pa & PAGE_MASK)); 130 } 131 132 void 133 _kvm_freevtop(kvm_t *kd) 134 { 135 struct vmstate *vm = kd->vmst; 136 137 if (kd->vmst->minidump) { 138 _kvm_minidump_freevtop(kd); 139 return; 140 } 141 142 if (vm->mmapbase != NULL) 143 munmap(vm->mmapbase, vm->mmapsize); 144 if (vm->PML4) 145 free(vm->PML4); 146 free(vm); 147 kd->vmst = NULL; 148 } 149 150 int 151 _kvm_initvtop(kvm_t *kd) 152 { 153 struct nlist nlists[2]; 154 u_long pa; 155 u_long kernbase; 156 pml4_entry_t *PML4; 157 Elf_Ehdr *ehdr; 158 size_t hdrsz; 159 char minihdr[8]; 160 struct pcb dumppcb; 161 162 if (pread(kd->pmfd, &minihdr, 8, 0) == 8) 163 if (memcmp(&minihdr, "minidump", 8) == 0) 164 return (_kvm_minidump_initvtop(kd)); 165 166 kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst)); 167 if (kd->vmst == 0) { 168 _kvm_err(kd, kd->program, "cannot allocate vm"); 169 return (-1); 170 } 171 kd->vmst->PML4 = 0; 172 173 if (_kvm_maphdrs(kd, sizeof(Elf_Ehdr)) == -1) 174 return (-1); 175 /* 176 * Check if this is indeed an ELF header. If not, assume old style 177 *dump or memory layout. 178 */ 179 ehdr = kd->vmst->mmapbase; 180 if (!IS_ELF(*ehdr)) { 181 kd->rawdump = 1; 182 munmap(kd->vmst->mmapbase, kd->vmst->mmapsize); 183 kd->vmst->mmapbase = NULL; 184 } else { 185 hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum; 186 if (_kvm_maphdrs(kd, hdrsz) == -1) 187 return (-1); 188 } 189 190 nlists[0].n_name = "kernbase"; 191 nlists[1].n_name = 0; 192 193 if (kvm_nlist(kd, nlists) != 0) { 194 _kvm_err(kd, kd->program, "bad namelist - no kernbase"); 195 return (-1); 196 } 197 kernbase = nlists[0].n_value; 198 199 nlists[0].n_name = "dumppcb"; 200 nlists[1].n_name = 0; 201 202 if (kvm_nlist(kd, nlists) != 0) { 203 _kvm_err(kd, kd->program, "bad namelist - no dumppcb"); 204 return (-1); 205 } 206 if (kvm_read(kd, (nlists[0].n_value - kernbase), &dumppcb, 207 sizeof(dumppcb)) != sizeof(dumppcb)) { 208 _kvm_err(kd, kd->program, "cannot read dumppcb"); 209 return (-1); 210 } 211 pa = dumppcb.pcb_cr3 & PG_FRAME; 212 213 PML4 = _kvm_malloc(kd, PAGE_SIZE); 214 if (kvm_read(kd, pa, PML4, PAGE_SIZE) != PAGE_SIZE) { 215 _kvm_err(kd, kd->program, "cannot read dumppcb"); 216 return (-1); 217 } 218 kd->vmst->PML4 = PML4; 219 return (0); 220 } 221 222 static int 223 _kvm_vatop(kvm_t *kd, u_long va, off_t *pa) 224 { 225 struct vmstate *vm; 226 u_long offset; 227 u_long pdpe_pa; 228 u_long pde_pa; 229 u_long pte_pa; 230 pml4_entry_t pml4e; 231 pdp_entry_t pdpe; 232 pd_entry_t pde; 233 pt_entry_t pte; 234 u_long pml4eindex; 235 u_long pdpeindex; 236 u_long pdeindex; 237 u_long pteindex; 238 u_long a; 239 off_t ofs; 240 size_t s; 241 242 vm = kd->vmst; 243 offset = va & (PAGE_SIZE - 1); 244 245 /* 246 * If we are initializing (kernel page table descriptor pointer 247 * not yet set) then return pa == va to avoid infinite recursion. 248 */ 249 if (vm->PML4 == NULL) { 250 s = _kvm_pa2off(kd, va, pa); 251 if (s == 0) { 252 _kvm_err(kd, kd->program, 253 "_kvm_vatop: bootstrap data not in dump"); 254 goto invalid; 255 } else 256 return (PAGE_SIZE - offset); 257 } 258 259 pml4eindex = (va >> PML4SHIFT) & (NPML4EPG - 1); 260 pml4e = vm->PML4[pml4eindex]; 261 if (((u_long)pml4e & X86_PG_V) == 0) { 262 _kvm_err(kd, kd->program, "_kvm_vatop: pml4e not valid"); 263 goto invalid; 264 } 265 266 pdpeindex = (va >> PDPSHIFT) & (NPDPEPG-1); 267 pdpe_pa = ((u_long)pml4e & PG_FRAME) + 268 (pdpeindex * sizeof(pdp_entry_t)); 269 270 s = _kvm_pa2off(kd, pdpe_pa, &ofs); 271 if (s < sizeof pdpe) { 272 _kvm_err(kd, kd->program, "_kvm_vatop: pdpe_pa not found"); 273 goto invalid; 274 } 275 if (lseek(kd->pmfd, ofs, 0) == -1) { 276 _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pdpe_pa"); 277 goto invalid; 278 } 279 if (read(kd->pmfd, &pdpe, sizeof pdpe) != sizeof pdpe) { 280 _kvm_syserr(kd, kd->program, "_kvm_vatop: read pdpe"); 281 goto invalid; 282 } 283 if (((u_long)pdpe & X86_PG_V) == 0) { 284 _kvm_err(kd, kd->program, "_kvm_vatop: pdpe not valid"); 285 goto invalid; 286 } 287 288 pdeindex = (va >> PDRSHIFT) & (NPDEPG-1); 289 pde_pa = ((u_long)pdpe & PG_FRAME) + (pdeindex * sizeof(pd_entry_t)); 290 291 s = _kvm_pa2off(kd, pde_pa, &ofs); 292 if (s < sizeof pde) { 293 _kvm_syserr(kd, kd->program, "_kvm_vatop: pde_pa not found"); 294 goto invalid; 295 } 296 if (lseek(kd->pmfd, ofs, 0) == -1) { 297 _kvm_err(kd, kd->program, "_kvm_vatop: lseek pde_pa"); 298 goto invalid; 299 } 300 if (read(kd->pmfd, &pde, sizeof pde) != sizeof pde) { 301 _kvm_syserr(kd, kd->program, "_kvm_vatop: read pde"); 302 goto invalid; 303 } 304 if (((u_long)pde & X86_PG_V) == 0) { 305 _kvm_err(kd, kd->program, "_kvm_vatop: pde not valid"); 306 goto invalid; 307 } 308 309 if ((u_long)pde & X86_PG_PS) { 310 /* 311 * No final-level page table; ptd describes one 2MB page. 312 */ 313 #define PAGE2M_MASK (NBPDR - 1) 314 #define PG_FRAME2M (~PAGE2M_MASK) 315 a = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK); 316 s = _kvm_pa2off(kd, a, pa); 317 if (s == 0) { 318 _kvm_err(kd, kd->program, 319 "_kvm_vatop: 2MB page address not in dump"); 320 goto invalid; 321 } else { 322 return (NBPDR - (va & PAGE2M_MASK)); 323 } 324 } 325 326 pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1); 327 pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pt_entry_t)); 328 329 s = _kvm_pa2off(kd, pte_pa, &ofs); 330 if (s < sizeof pte) { 331 _kvm_err(kd, kd->program, "_kvm_vatop: pte_pa not found"); 332 goto invalid; 333 } 334 if (lseek(kd->pmfd, ofs, 0) == -1) { 335 _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek"); 336 goto invalid; 337 } 338 if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) { 339 _kvm_syserr(kd, kd->program, "_kvm_vatop: read"); 340 goto invalid; 341 } 342 if (((u_long)pte & X86_PG_V) == 0) { 343 _kvm_err(kd, kd->program, "_kvm_vatop: pte not valid"); 344 goto invalid; 345 } 346 347 a = ((u_long)pte & PG_FRAME) + offset; 348 s = _kvm_pa2off(kd, a, pa); 349 if (s == 0) { 350 _kvm_err(kd, kd->program, "_kvm_vatop: address not in dump"); 351 goto invalid; 352 } else 353 return (PAGE_SIZE - offset); 354 355 invalid: 356 _kvm_err(kd, 0, "invalid address (0x%lx)", va); 357 return (0); 358 } 359 360 int 361 _kvm_kvatop(kvm_t *kd, u_long va, off_t *pa) 362 { 363 if (kd->vmst->minidump) 364 return (_kvm_minidump_kvatop(kd, va, pa)); 365 366 if (kvm_ishost(kd)) { 367 _kvm_err(kd, 0, "kvm_vatop called in live kernel!"); 368 return((off_t)0); 369 } 370 371 return (_kvm_vatop(kd, va, pa)); 372 } 373