kvm_minidump_amd64.c revision 159246
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: head/lib/libkvm/kvm_minidump_amd64.c 159246 2006-06-05 08:51:14Z delphij $"); 28 29/* 30 * AMD64 machine dependent routines for kvm and minidumps. 31 */ 32 33#include <sys/param.h> 34#include <sys/user.h> 35#include <sys/proc.h> 36#include <sys/stat.h> 37#include <sys/mman.h> 38#include <sys/fnv_hash.h> 39#include <stdlib.h> 40#include <strings.h> 41#include <unistd.h> 42#include <nlist.h> 43#include <kvm.h> 44 45#include <vm/vm.h> 46#include <vm/vm_param.h> 47 48#include <machine/elf.h> 49#include <machine/cpufunc.h> 50#include <machine/minidump.h> 51 52#include <limits.h> 53 54#include "kvm_private.h" 55 56struct hpte { 57 struct hpte *next; 58 vm_paddr_t pa; 59 int64_t off; 60}; 61 62#define HPT_SIZE 1024 63 64/* minidump must be the first item! */ 65struct vmstate { 66 int minidump; /* 1 = minidump mode */ 67 struct minidumphdr hdr; 68 void *hpt_head[HPT_SIZE]; 69 uint64_t *bitmap; 70 uint64_t *ptemap; 71}; 72 73static void 74hpt_insert(kvm_t *kd, vm_paddr_t pa, int64_t off) 75{ 76 struct hpte *hpte; 77 uint32_t fnv = FNV1_32_INIT; 78 79 fnv = fnv_32_buf(&pa, sizeof(pa), fnv); 80 fnv &= (HPT_SIZE - 1); 81 hpte = malloc(sizeof(*hpte)); 82 hpte->pa = pa; 83 hpte->off = off; 84 hpte->next = kd->vmst->hpt_head[fnv]; 85 kd->vmst->hpt_head[fnv] = hpte; 86} 87 88static int64_t 89hpt_find(kvm_t *kd, vm_paddr_t pa) 90{ 91 struct hpte *hpte; 92 uint32_t fnv = FNV1_32_INIT; 93 94 fnv = fnv_32_buf(&pa, sizeof(pa), fnv); 95 fnv &= (HPT_SIZE - 1); 96 for (hpte = kd->vmst->hpt_head[fnv]; hpte != NULL; hpte = hpte->next) { 97 if (pa == hpte->pa) 98 return (hpte->off); 99 } 100 return (-1); 101} 102 103static int 104inithash(kvm_t *kd, uint64_t *base, int len, off_t off) 105{ 106 uint64_t idx; 107 uint64_t bit, bits; 108 vm_paddr_t pa; 109 110 for (idx = 0; idx < len / sizeof(*base); idx++) { 111 bits = base[idx]; 112 while (bits) { 113 bit = bsfq(bits); 114 bits &= ~(1ul << bit); 115 pa = (idx * sizeof(*base) * NBBY + bit) * PAGE_SIZE; 116 hpt_insert(kd, pa, off); 117 off += PAGE_SIZE; 118 } 119 } 120 return (off); 121} 122 123void 124_kvm_minidump_freevtop(kvm_t *kd) 125{ 126 struct vmstate *vm = kd->vmst; 127 128 if (vm->bitmap) 129 free(vm->bitmap); 130 if (vm->ptemap) 131 free(vm->ptemap); 132 free(vm); 133 kd->vmst = NULL; 134} 135 136int 137_kvm_minidump_initvtop(kvm_t *kd) 138{ 139 u_long pa; 140 struct vmstate *vmst; 141 off_t off; 142 143 vmst = _kvm_malloc(kd, sizeof(*vmst)); 144 if (vmst == 0) { 145 _kvm_err(kd, kd->program, "cannot allocate vm"); 146 return (-1); 147 } 148 kd->vmst = vmst; 149 bzero(vmst, sizeof(*vmst)); 150 vmst->minidump = 1; 151 if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) != 152 sizeof(vmst->hdr)) { 153 _kvm_err(kd, kd->program, "cannot read dump header"); 154 return (-1); 155 } 156 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) { 157 _kvm_err(kd, kd->program, "not a minidump for this platform"); 158 return (-1); 159 } 160 if (vmst->hdr.version != MINIDUMP_VERSION) { 161 _kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d", 162 MINIDUMP_VERSION, vmst->hdr.version); 163 return (-1); 164 } 165 166 /* Skip header and msgbuf */ 167 off = PAGE_SIZE + round_page(vmst->hdr.msgbufsize); 168 169 vmst->bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize); 170 if (vmst->bitmap == NULL) { 171 _kvm_err(kd, kd->program, "cannot allocate %d bytes for bitmap", vmst->hdr.bitmapsize); 172 return (-1); 173 } 174 if (pread(kd->pmfd, vmst->bitmap, vmst->hdr.bitmapsize, off) != 175 vmst->hdr.bitmapsize) { 176 _kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap", vmst->hdr.bitmapsize); 177 return (-1); 178 } 179 off += round_page(vmst->hdr.bitmapsize); 180 181 vmst->ptemap = _kvm_malloc(kd, vmst->hdr.ptesize); 182 if (vmst->ptemap == NULL) { 183 _kvm_err(kd, kd->program, "cannot allocate %d bytes for ptemap", vmst->hdr.ptesize); 184 return (-1); 185 } 186 if (pread(kd->pmfd, vmst->ptemap, vmst->hdr.ptesize, off) != 187 vmst->hdr.ptesize) { 188 _kvm_err(kd, kd->program, "cannot read %d bytes for ptemap", vmst->hdr.ptesize); 189 return (-1); 190 } 191 off += vmst->hdr.ptesize; 192 193 /* build physical address hash table for sparse pages */ 194 inithash(kd, vmst->bitmap, vmst->hdr.bitmapsize, off); 195 196 return (0); 197} 198 199static int 200_kvm_minidump_vatop(kvm_t *kd, u_long va, off_t *pa) 201{ 202 struct vmstate *vm; 203 u_long offset; 204 pt_entry_t pte; 205 u_long pteindex; 206 int i; 207 u_long a; 208 off_t ofs; 209 210 vm = kd->vmst; 211 offset = va & (PAGE_SIZE - 1); 212 213 if (va >= vm->hdr.kernbase) { 214 pteindex = (va - vm->hdr.kernbase) >> PAGE_SHIFT; 215 pte = vm->ptemap[pteindex]; 216 if (((u_long)pte & PG_V) == 0) { 217 _kvm_err(kd, kd->program, "_kvm_vatop: pte not valid"); 218 goto invalid; 219 } 220 a = pte & PG_FRAME; 221 ofs = hpt_find(kd, a); 222 if (ofs == -1) { 223 _kvm_err(kd, kd->program, "_kvm_vatop: physical address 0x%lx not in minidump", a); 224 goto invalid; 225 } 226 *pa = ofs + offset; 227 return (PAGE_SIZE - offset); 228 } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) { 229 a = (va - vm->hdr.dmapbase) & ~PAGE_MASK; 230 ofs = hpt_find(kd, a); 231 if (ofs == -1) { 232 _kvm_err(kd, kd->program, "_kvm_vatop: direct map address 0x%lx not in minidump", va); 233 goto invalid; 234 } 235 *pa = ofs + offset; 236 return (PAGE_SIZE - offset); 237 } else { 238 _kvm_err(kd, kd->program, "_kvm_vatop: virtual address 0x%lx not minidumped", va); 239 goto invalid; 240 } 241 242invalid: 243 _kvm_err(kd, 0, "invalid address (0x%lx)", va); 244 return (0); 245} 246 247int 248_kvm_minidump_kvatop(kvm_t *kd, u_long va, off_t *pa) 249{ 250 251 if (ISALIVE(kd)) { 252 _kvm_err(kd, 0, "kvm_kvatop called in live kernel!"); 253 return (0); 254 } 255 return (_kvm_minidump_vatop(kd, va, pa)); 256} 257