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/proc.h> 45 #include <sys/stat.h> 46 #include <sys/mman.h> 47 #include <sys/elf_common.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <unistd.h> 51 #include <nlist.h> 52 53 #include <cpu/pmap.h> 54 #include <vm/vm.h> 55 #include <vm/vm_param.h> 56 57 #include <machine/elf.h> 58 59 #include <limits.h> 60 61 #include "kvm.h" 62 #include "kvm_private.h" 63 64 #ifndef btop 65 #define btop(x) (x86_64_btop(x)) 66 #define ptob(x) (x86_64_ptob(x)) 67 #endif 68 69 struct vmstate { 70 int minidump; /* 1 = minidump mode */ 71 void *mmapbase; 72 size_t mmapsize; 73 pml4_entry_t *PML4; 74 }; 75 76 /* 77 * Map the ELF headers into the process' address space. We do this in two 78 * steps: first the ELF header itself and using that information the whole 79 * set of headers. (Taken from kvm_ia64.c) 80 */ 81 static int 82 _kvm_maphdrs(kvm_t *kd, size_t sz) 83 { 84 struct vmstate *vm = kd->vmst; 85 86 if (kd->vmst->minidump) { 87 _kvm_minidump_freevtop(kd); 88 return (0); 89 } 90 91 /* munmap() previous mmap(). */ 92 if (vm->mmapbase != NULL) { 93 munmap(vm->mmapbase, vm->mmapsize); 94 vm->mmapbase = NULL; 95 } 96 97 vm->mmapsize = sz; 98 vm->mmapbase = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0); 99 if (vm->mmapbase == MAP_FAILED) { 100 _kvm_err(kd, kd->program, "cannot mmap corefile"); 101 return (-1); 102 } 103 return (0); 104 } 105 106 /* 107 * Translate a physical memory address to a file-offset in the crash-dump. 108 * (Taken from kvm_ia64.c) 109 */ 110 static size_t 111 _kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs) 112 { 113 Elf_Ehdr *e = kd->vmst->mmapbase; 114 Elf_Phdr *p; 115 int n; 116 117 if (kd->rawdump) { 118 *ofs = pa; 119 return (PAGE_SIZE - ((size_t)pa & PAGE_MASK)); 120 } 121 122 p = (Elf_Phdr*)((char*)e + e->e_phoff); 123 n = e->e_phnum; 124 125 while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz)) 126 p++, n--; 127 if (n == 0) 128 return (0); 129 *ofs = (pa - p->p_paddr) + p->p_offset; 130 return (PAGE_SIZE - ((size_t)pa & PAGE_MASK)); 131 } 132 133 void 134 _kvm_freevtop(kvm_t *kd) 135 { 136 struct vmstate *vm = kd->vmst; 137 138 if (kd->vmst->minidump) { 139 _kvm_minidump_freevtop(kd); 140 return; 141 } 142 143 if (vm->mmapbase != NULL) 144 munmap(vm->mmapbase, vm->mmapsize); 145 if (vm->PML4) 146 free(vm->PML4); 147 free(vm); 148 kd->vmst = NULL; 149 } 150 151 int 152 _kvm_initvtop(kvm_t *kd) 153 { 154 struct nlist nlists[2]; 155 u_long pa; 156 u_long kernbase; 157 pml4_entry_t *PML4; 158 Elf_Ehdr *ehdr; 159 size_t hdrsz; 160 char minihdr[8]; 161 struct pcb dumppcb; 162 163 if (pread(kd->pmfd, &minihdr, 8, 0) == 8) 164 if (memcmp(&minihdr, "minidump", 8) == 0) 165 return (_kvm_minidump_initvtop(kd)); 166 167 kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst)); 168 if (kd->vmst == 0) { 169 _kvm_err(kd, kd->program, "cannot allocate vm"); 170 return (-1); 171 } 172 kd->vmst->PML4 = 0; 173 174 if (_kvm_maphdrs(kd, sizeof(Elf_Ehdr)) == -1) 175 return (-1); 176 /* 177 * Check if this is indeed an ELF header. If not, assume old style 178 *dump or memory layout. 179 */ 180 ehdr = kd->vmst->mmapbase; 181 if (!IS_ELF(*ehdr)) { 182 kd->rawdump = 1; 183 munmap(kd->vmst->mmapbase, kd->vmst->mmapsize); 184 kd->vmst->mmapbase = NULL; 185 } else { 186 hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum; 187 if (_kvm_maphdrs(kd, hdrsz) == -1) 188 return (-1); 189 } 190 191 nlists[0].n_name = "kernbase"; 192 nlists[1].n_name = 0; 193 194 if (kvm_nlist(kd, nlists) != 0) { 195 _kvm_err(kd, kd->program, "bad namelist - no kernbase"); 196 return (-1); 197 } 198 kernbase = nlists[0].n_value; 199 200 nlists[0].n_name = "dumppcb"; 201 nlists[1].n_name = 0; 202 203 if (kvm_nlist(kd, nlists) != 0) { 204 _kvm_err(kd, kd->program, "bad namelist - no dumppcb"); 205 return (-1); 206 } 207 if (kvm_read(kd, (nlists[0].n_value - kernbase), &dumppcb, 208 sizeof(dumppcb)) != sizeof(dumppcb)) { 209 _kvm_err(kd, kd->program, "cannot read dumppcb"); 210 return (-1); 211 } 212 pa = dumppcb.pcb_cr3 & PG_FRAME; 213 214 PML4 = _kvm_malloc(kd, PAGE_SIZE); 215 if (kvm_read(kd, pa, PML4, PAGE_SIZE) != PAGE_SIZE) { 216 _kvm_err(kd, kd->program, "cannot read dumppcb"); 217 return (-1); 218 } 219 kd->vmst->PML4 = PML4; 220 return (0); 221 } 222 223 static int 224 _kvm_vatop(kvm_t *kd, u_long va, off_t *pa) 225 { 226 struct vmstate *vm; 227 u_long offset; 228 u_long pdpe_pa; 229 u_long pde_pa; 230 u_long pte_pa; 231 pml4_entry_t pml4e; 232 pdp_entry_t pdpe; 233 pd_entry_t pde; 234 pt_entry_t pte; 235 u_long pml4eindex; 236 u_long pdpeindex; 237 u_long pdeindex; 238 u_long pteindex; 239 u_long a; 240 off_t ofs; 241 size_t s; 242 243 vm = kd->vmst; 244 offset = va & (PAGE_SIZE - 1); 245 246 /* 247 * If we are initializing (kernel page table descriptor pointer 248 * not yet set) then return pa == va to avoid infinite recursion. 249 */ 250 if (vm->PML4 == NULL) { 251 s = _kvm_pa2off(kd, va, pa); 252 if (s == 0) { 253 _kvm_err(kd, kd->program, 254 "_kvm_vatop: bootstrap data not in dump"); 255 goto invalid; 256 } else 257 return (PAGE_SIZE - offset); 258 } 259 260 pml4eindex = (va >> PML4SHIFT) & (NPML4EPG - 1); 261 pml4e = vm->PML4[pml4eindex]; 262 if (((u_long)pml4e & X86_PG_V) == 0) { 263 _kvm_err(kd, kd->program, "_kvm_vatop: pml4e not valid"); 264 goto invalid; 265 } 266 267 pdpeindex = (va >> PDPSHIFT) & (NPDPEPG-1); 268 pdpe_pa = ((u_long)pml4e & PG_FRAME) + 269 (pdpeindex * sizeof(pdp_entry_t)); 270 271 s = _kvm_pa2off(kd, pdpe_pa, &ofs); 272 if (s < sizeof pdpe) { 273 _kvm_err(kd, kd->program, "_kvm_vatop: pdpe_pa not found"); 274 goto invalid; 275 } 276 if (lseek(kd->pmfd, ofs, 0) == -1) { 277 _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pdpe_pa"); 278 goto invalid; 279 } 280 if (read(kd->pmfd, &pdpe, sizeof pdpe) != sizeof pdpe) { 281 _kvm_syserr(kd, kd->program, "_kvm_vatop: read pdpe"); 282 goto invalid; 283 } 284 if (((u_long)pdpe & X86_PG_V) == 0) { 285 _kvm_err(kd, kd->program, "_kvm_vatop: pdpe not valid"); 286 goto invalid; 287 } 288 289 pdeindex = (va >> PDRSHIFT) & (NPDEPG-1); 290 pde_pa = ((u_long)pdpe & PG_FRAME) + (pdeindex * sizeof(pd_entry_t)); 291 292 s = _kvm_pa2off(kd, pde_pa, &ofs); 293 if (s < sizeof pde) { 294 _kvm_syserr(kd, kd->program, "_kvm_vatop: pde_pa not found"); 295 goto invalid; 296 } 297 if (lseek(kd->pmfd, ofs, 0) == -1) { 298 _kvm_err(kd, kd->program, "_kvm_vatop: lseek pde_pa"); 299 goto invalid; 300 } 301 if (read(kd->pmfd, &pde, sizeof pde) != sizeof pde) { 302 _kvm_syserr(kd, kd->program, "_kvm_vatop: read pde"); 303 goto invalid; 304 } 305 if (((u_long)pde & X86_PG_V) == 0) { 306 _kvm_err(kd, kd->program, "_kvm_vatop: pde not valid"); 307 goto invalid; 308 } 309 310 if ((u_long)pde & X86_PG_PS) { 311 /* 312 * No final-level page table; ptd describes one 2MB page. 313 */ 314 #define PAGE2M_MASK (NBPDR - 1) 315 #define PG_FRAME2M (~PAGE2M_MASK) 316 a = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK); 317 s = _kvm_pa2off(kd, a, pa); 318 if (s == 0) { 319 _kvm_err(kd, kd->program, 320 "_kvm_vatop: 2MB page address not in dump"); 321 goto invalid; 322 } else { 323 return (NBPDR - (va & PAGE2M_MASK)); 324 } 325 } 326 327 pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1); 328 pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pt_entry_t)); 329 330 s = _kvm_pa2off(kd, pte_pa, &ofs); 331 if (s < sizeof pte) { 332 _kvm_err(kd, kd->program, "_kvm_vatop: pte_pa not found"); 333 goto invalid; 334 } 335 if (lseek(kd->pmfd, ofs, 0) == -1) { 336 _kvm_syserr(kd, kd->program, "_kvm_vatop: lseek"); 337 goto invalid; 338 } 339 if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) { 340 _kvm_syserr(kd, kd->program, "_kvm_vatop: read"); 341 goto invalid; 342 } 343 if (((u_long)pte & X86_PG_V) == 0) { 344 _kvm_err(kd, kd->program, "_kvm_vatop: pte not valid"); 345 goto invalid; 346 } 347 348 a = ((u_long)pte & PG_FRAME) + offset; 349 s = _kvm_pa2off(kd, a, pa); 350 if (s == 0) { 351 _kvm_err(kd, kd->program, "_kvm_vatop: address not in dump"); 352 goto invalid; 353 } else 354 return (PAGE_SIZE - offset); 355 356 invalid: 357 _kvm_err(kd, 0, "invalid address (0x%lx)", va); 358 return (0); 359 } 360 361 int 362 _kvm_kvatop(kvm_t *kd, u_long va, off_t *pa) 363 { 364 if (kd->vmst->minidump) 365 return (_kvm_minidump_kvatop(kd, va, pa)); 366 367 if (kvm_ishost(kd)) { 368 _kvm_err(kd, 0, "kvm_vatop called in live kernel!"); 369 return((off_t)0); 370 } 371 372 return (_kvm_vatop(kd, va, pa)); 373 } 374