kvm_minidump_amd64.c revision 183985
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 183985 2008-10-17 20:09:00Z 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 vmst->minidump = 1; 150 if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) != 151 sizeof(vmst->hdr)) { 152 _kvm_err(kd, kd->program, "cannot read dump header"); 153 return (-1); 154 } 155 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) { 156 _kvm_err(kd, kd->program, "not a minidump for this platform"); 157 return (-1); 158 } 159 if (vmst->hdr.version != MINIDUMP_VERSION) { 160 _kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d", 161 MINIDUMP_VERSION, vmst->hdr.version); 162 return (-1); 163 } 164 165 /* Skip header and msgbuf */ 166 off = PAGE_SIZE + round_page(vmst->hdr.msgbufsize); 167 168 vmst->bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize); 169 if (vmst->bitmap == NULL) { 170 _kvm_err(kd, kd->program, "cannot allocate %d bytes for bitmap", vmst->hdr.bitmapsize); 171 return (-1); 172 } 173 if (pread(kd->pmfd, vmst->bitmap, vmst->hdr.bitmapsize, off) != 174 vmst->hdr.bitmapsize) { 175 _kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap", vmst->hdr.bitmapsize); 176 return (-1); 177 } 178 off += round_page(vmst->hdr.bitmapsize); 179 180 vmst->ptemap = _kvm_malloc(kd, vmst->hdr.ptesize); 181 if (vmst->ptemap == NULL) { 182 _kvm_err(kd, kd->program, "cannot allocate %d bytes for ptemap", vmst->hdr.ptesize); 183 return (-1); 184 } 185 if (pread(kd->pmfd, vmst->ptemap, vmst->hdr.ptesize, off) != 186 vmst->hdr.ptesize) { 187 _kvm_err(kd, kd->program, "cannot read %d bytes for ptemap", vmst->hdr.ptesize); 188 return (-1); 189 } 190 off += vmst->hdr.ptesize; 191 192 /* build physical address hash table for sparse pages */ 193 inithash(kd, vmst->bitmap, vmst->hdr.bitmapsize, off); 194 195 return (0); 196} 197 198static int 199_kvm_minidump_vatop(kvm_t *kd, u_long va, off_t *pa) 200{ 201 struct vmstate *vm; 202 u_long offset; 203 pt_entry_t pte; 204 u_long pteindex; 205 int i; 206 u_long a; 207 off_t ofs; 208 209 vm = kd->vmst; 210 offset = va & (PAGE_SIZE - 1); 211 212 if (va >= vm->hdr.kernbase) { 213 pteindex = (va - vm->hdr.kernbase) >> PAGE_SHIFT; 214 pte = vm->ptemap[pteindex]; 215 if (((u_long)pte & PG_V) == 0) { 216 _kvm_err(kd, kd->program, "_kvm_vatop: pte not valid"); 217 goto invalid; 218 } 219 a = pte & PG_FRAME; 220 ofs = hpt_find(kd, a); 221 if (ofs == -1) { 222 _kvm_err(kd, kd->program, "_kvm_vatop: physical address 0x%lx not in minidump", a); 223 goto invalid; 224 } 225 *pa = ofs + offset; 226 return (PAGE_SIZE - offset); 227 } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) { 228 a = (va - vm->hdr.dmapbase) & ~PAGE_MASK; 229 ofs = hpt_find(kd, a); 230 if (ofs == -1) { 231 _kvm_err(kd, kd->program, "_kvm_vatop: direct map address 0x%lx not in minidump", va); 232 goto invalid; 233 } 234 *pa = ofs + offset; 235 return (PAGE_SIZE - offset); 236 } else { 237 _kvm_err(kd, kd->program, "_kvm_vatop: virtual address 0x%lx not minidumped", va); 238 goto invalid; 239 } 240 241invalid: 242 _kvm_err(kd, 0, "invalid address (0x%lx)", va); 243 return (0); 244} 245 246int 247_kvm_minidump_kvatop(kvm_t *kd, u_long va, off_t *pa) 248{ 249 250 if (ISALIVE(kd)) { 251 _kvm_err(kd, 0, "kvm_kvatop called in live kernel!"); 252 return (0); 253 } 254 return (_kvm_minidump_vatop(kd, va, pa)); 255} 256