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("$FreeBSD$");
28
29 /*
30 * AMD64 machine dependent routines for kvm and minidumps.
31 */
32
33 #include <sys/param.h>
34 #include <sys/endian.h>
35 #include <stdint.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 #include <kvm.h>
40
41 #include "../../sys/amd64/include/minidump.h"
42
43 #include <limits.h>
44
45 #include "kvm_private.h"
46 #include "kvm_amd64.h"
47
48 #define amd64_round_page(x) roundup2((kvaddr_t)(x), AMD64_PAGE_SIZE)
49
50 struct vmstate {
51 struct minidumphdr hdr;
52 struct hpt hpt;
53 amd64_pte_t *page_map;
54 };
55
56 static int
_amd64_minidump_probe(kvm_t * kd)57 _amd64_minidump_probe(kvm_t *kd)
58 {
59
60 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_X86_64) &&
61 _kvm_is_minidump(kd));
62 }
63
64 static void
_amd64_minidump_freevtop(kvm_t * kd)65 _amd64_minidump_freevtop(kvm_t *kd)
66 {
67 struct vmstate *vm = kd->vmst;
68
69 _kvm_hpt_free(&vm->hpt);
70 if (vm->page_map)
71 free(vm->page_map);
72 free(vm);
73 kd->vmst = NULL;
74 }
75
76 static int
_amd64_minidump_initvtop(kvm_t * kd)77 _amd64_minidump_initvtop(kvm_t *kd)
78 {
79 struct vmstate *vmst;
80 uint64_t *bitmap;
81 off_t off;
82
83 vmst = _kvm_malloc(kd, sizeof(*vmst));
84 if (vmst == 0) {
85 _kvm_err(kd, kd->program, "cannot allocate vm");
86 return (-1);
87 }
88 kd->vmst = vmst;
89 if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
90 sizeof(vmst->hdr)) {
91 _kvm_err(kd, kd->program, "cannot read dump header");
92 return (-1);
93 }
94 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) {
95 _kvm_err(kd, kd->program, "not a minidump for this platform");
96 return (-1);
97 }
98
99 /*
100 * NB: amd64 minidump header is binary compatible between version 1
101 * and version 2; this may not be the case for the future versions.
102 */
103 vmst->hdr.version = le32toh(vmst->hdr.version);
104 if (vmst->hdr.version != MINIDUMP_VERSION && vmst->hdr.version != 1) {
105 _kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d",
106 MINIDUMP_VERSION, vmst->hdr.version);
107 return (-1);
108 }
109 vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize);
110 vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize);
111 vmst->hdr.pmapsize = le32toh(vmst->hdr.pmapsize);
112 vmst->hdr.kernbase = le64toh(vmst->hdr.kernbase);
113 vmst->hdr.dmapbase = le64toh(vmst->hdr.dmapbase);
114 vmst->hdr.dmapend = le64toh(vmst->hdr.dmapend);
115
116 /* Skip header and msgbuf */
117 off = AMD64_PAGE_SIZE + amd64_round_page(vmst->hdr.msgbufsize);
118
119 bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize);
120 if (bitmap == NULL) {
121 _kvm_err(kd, kd->program, "cannot allocate %d bytes for bitmap", vmst->hdr.bitmapsize);
122 return (-1);
123 }
124 if (pread(kd->pmfd, bitmap, vmst->hdr.bitmapsize, off) !=
125 (ssize_t)vmst->hdr.bitmapsize) {
126 _kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap", vmst->hdr.bitmapsize);
127 free(bitmap);
128 return (-1);
129 }
130 off += amd64_round_page(vmst->hdr.bitmapsize);
131
132 vmst->page_map = _kvm_malloc(kd, vmst->hdr.pmapsize);
133 if (vmst->page_map == NULL) {
134 _kvm_err(kd, kd->program, "cannot allocate %d bytes for page_map", vmst->hdr.pmapsize);
135 free(bitmap);
136 return (-1);
137 }
138 if (pread(kd->pmfd, vmst->page_map, vmst->hdr.pmapsize, off) !=
139 (ssize_t)vmst->hdr.pmapsize) {
140 _kvm_err(kd, kd->program, "cannot read %d bytes for page_map", vmst->hdr.pmapsize);
141 free(bitmap);
142 return (-1);
143 }
144 off += vmst->hdr.pmapsize;
145
146 /* build physical address hash table for sparse pages */
147 _kvm_hpt_init(kd, &vmst->hpt, bitmap, vmst->hdr.bitmapsize, off,
148 AMD64_PAGE_SIZE, sizeof(*bitmap));
149 free(bitmap);
150
151 return (0);
152 }
153
154 static int
_amd64_minidump_vatop_v1(kvm_t * kd,kvaddr_t va,off_t * pa)155 _amd64_minidump_vatop_v1(kvm_t *kd, kvaddr_t va, off_t *pa)
156 {
157 struct vmstate *vm;
158 amd64_physaddr_t offset;
159 amd64_pte_t pte;
160 kvaddr_t pteindex;
161 amd64_physaddr_t a;
162 off_t ofs;
163
164 vm = kd->vmst;
165 offset = va & AMD64_PAGE_MASK;
166
167 if (va >= vm->hdr.kernbase) {
168 pteindex = (va - vm->hdr.kernbase) >> AMD64_PAGE_SHIFT;
169 if (pteindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
170 goto invalid;
171 pte = le64toh(vm->page_map[pteindex]);
172 if ((pte & AMD64_PG_V) == 0) {
173 _kvm_err(kd, kd->program,
174 "_amd64_minidump_vatop_v1: pte not valid");
175 goto invalid;
176 }
177 a = pte & AMD64_PG_FRAME;
178 ofs = _kvm_hpt_find(&vm->hpt, a);
179 if (ofs == -1) {
180 _kvm_err(kd, kd->program,
181 "_amd64_minidump_vatop_v1: physical address 0x%jx not in minidump",
182 (uintmax_t)a);
183 goto invalid;
184 }
185 *pa = ofs + offset;
186 return (AMD64_PAGE_SIZE - offset);
187 } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
188 a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
189 ofs = _kvm_hpt_find(&vm->hpt, a);
190 if (ofs == -1) {
191 _kvm_err(kd, kd->program,
192 "_amd64_minidump_vatop_v1: direct map address 0x%jx not in minidump",
193 (uintmax_t)va);
194 goto invalid;
195 }
196 *pa = ofs + offset;
197 return (AMD64_PAGE_SIZE - offset);
198 } else {
199 _kvm_err(kd, kd->program,
200 "_amd64_minidump_vatop_v1: virtual address 0x%jx not minidumped",
201 (uintmax_t)va);
202 goto invalid;
203 }
204
205 invalid:
206 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
207 return (0);
208 }
209
210 static int
_amd64_minidump_vatop(kvm_t * kd,kvaddr_t va,off_t * pa)211 _amd64_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
212 {
213 amd64_pte_t pt[AMD64_NPTEPG];
214 struct vmstate *vm;
215 amd64_physaddr_t offset;
216 amd64_pde_t pde;
217 amd64_pte_t pte;
218 kvaddr_t pteindex;
219 kvaddr_t pdeindex;
220 amd64_physaddr_t a;
221 off_t ofs;
222
223 vm = kd->vmst;
224 offset = va & AMD64_PAGE_MASK;
225
226 if (va >= vm->hdr.kernbase) {
227 pdeindex = (va - vm->hdr.kernbase) >> AMD64_PDRSHIFT;
228 if (pdeindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
229 goto invalid;
230 pde = le64toh(vm->page_map[pdeindex]);
231 if ((pde & AMD64_PG_V) == 0) {
232 _kvm_err(kd, kd->program,
233 "_amd64_minidump_vatop: pde not valid");
234 goto invalid;
235 }
236 if ((pde & AMD64_PG_PS) == 0) {
237 a = pde & AMD64_PG_FRAME;
238 ofs = _kvm_hpt_find(&vm->hpt, a);
239 if (ofs == -1) {
240 _kvm_err(kd, kd->program,
241 "_amd64_minidump_vatop: pt physical address 0x%jx not in minidump",
242 (uintmax_t)a);
243 goto invalid;
244 }
245 /* TODO: Just read the single PTE */
246 if (pread(kd->pmfd, &pt, AMD64_PAGE_SIZE, ofs) !=
247 AMD64_PAGE_SIZE) {
248 _kvm_err(kd, kd->program,
249 "cannot read %d bytes for page table",
250 AMD64_PAGE_SIZE);
251 return (-1);
252 }
253 pteindex = (va >> AMD64_PAGE_SHIFT) &
254 (AMD64_NPTEPG - 1);
255 pte = le64toh(pt[pteindex]);
256 if ((pte & AMD64_PG_V) == 0) {
257 _kvm_err(kd, kd->program,
258 "_amd64_minidump_vatop: pte not valid");
259 goto invalid;
260 }
261 a = pte & AMD64_PG_FRAME;
262 } else {
263 a = pde & AMD64_PG_PS_FRAME;
264 a += (va & AMD64_PDRMASK) ^ offset;
265 }
266 ofs = _kvm_hpt_find(&vm->hpt, a);
267 if (ofs == -1) {
268 _kvm_err(kd, kd->program,
269 "_amd64_minidump_vatop: physical address 0x%jx not in minidump",
270 (uintmax_t)a);
271 goto invalid;
272 }
273 *pa = ofs + offset;
274 return (AMD64_PAGE_SIZE - offset);
275 } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
276 a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
277 ofs = _kvm_hpt_find(&vm->hpt, a);
278 if (ofs == -1) {
279 _kvm_err(kd, kd->program,
280 "_amd64_minidump_vatop: direct map address 0x%jx not in minidump",
281 (uintmax_t)va);
282 goto invalid;
283 }
284 *pa = ofs + offset;
285 return (AMD64_PAGE_SIZE - offset);
286 } else {
287 _kvm_err(kd, kd->program,
288 "_amd64_minidump_vatop: virtual address 0x%jx not minidumped",
289 (uintmax_t)va);
290 goto invalid;
291 }
292
293 invalid:
294 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
295 return (0);
296 }
297
298 static int
_amd64_minidump_kvatop(kvm_t * kd,kvaddr_t va,off_t * pa)299 _amd64_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
300 {
301
302 if (ISALIVE(kd)) {
303 _kvm_err(kd, 0,
304 "_amd64_minidump_kvatop called in live kernel!");
305 return (0);
306 }
307 if (((struct vmstate *)kd->vmst)->hdr.version == 1)
308 return (_amd64_minidump_vatop_v1(kd, va, pa));
309 else
310 return (_amd64_minidump_vatop(kd, va, pa));
311 }
312
313 struct kvm_arch kvm_amd64_minidump = {
314 .ka_probe = _amd64_minidump_probe,
315 .ka_initvtop = _amd64_minidump_initvtop,
316 .ka_freevtop = _amd64_minidump_freevtop,
317 .ka_kvatop = _amd64_minidump_kvatop,
318 .ka_native = _amd64_native,
319 };
320
321 KVM_ARCH(kvm_amd64_minidump);
322