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 * From: FreeBSD: src/lib/libkvm/kvm_minidump_amd64.c r261799
26 */
27
28 #include <sys/cdefs.h>
29 /*
30 * ARM64 (AArch64) machine dependent routines for kvm and minidumps.
31 */
32
33 #include <sys/param.h>
34 #include <stdint.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <unistd.h>
38 #include <vm/vm.h>
39 #include <kvm.h>
40
41 #include "../../sys/arm64/include/minidump.h"
42
43 #include <limits.h>
44
45 #include "kvm_private.h"
46 #include "kvm_aarch64.h"
47
48 #define aarch64_round_page(x, size) roundup2((kvaddr_t)(x), size)
49 #define aarch64_trunc_page(x, size) rounddown2((kvaddr_t)(x), size)
50
51 struct vmstate {
52 struct minidumphdr hdr;
53 size_t page_size;
54 u_int l3_shift;
55 };
56
57 static aarch64_pte_t
_aarch64_pte_get(kvm_t * kd,u_long pteindex)58 _aarch64_pte_get(kvm_t *kd, u_long pteindex)
59 {
60 aarch64_pte_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte));
61
62 return le64toh(*pte);
63 }
64
65 static int
_aarch64_minidump_probe(kvm_t * kd)66 _aarch64_minidump_probe(kvm_t *kd)
67 {
68
69 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_AARCH64) &&
70 _kvm_is_minidump(kd));
71 }
72
73 static void
_aarch64_minidump_freevtop(kvm_t * kd)74 _aarch64_minidump_freevtop(kvm_t *kd)
75 {
76 struct vmstate *vm = kd->vmst;
77
78 free(vm);
79 kd->vmst = NULL;
80 }
81
82 static int
_aarch64_minidump_initvtop(kvm_t * kd)83 _aarch64_minidump_initvtop(kvm_t *kd)
84 {
85 struct vmstate *vmst;
86 off_t off, dump_avail_off, sparse_off;
87
88 vmst = _kvm_malloc(kd, sizeof(*vmst));
89 if (vmst == NULL) {
90 _kvm_err(kd, kd->program, "cannot allocate vm");
91 return (-1);
92 }
93 kd->vmst = vmst;
94 if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
95 sizeof(vmst->hdr)) {
96 _kvm_err(kd, kd->program, "cannot read dump header");
97 return (-1);
98 }
99 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
100 sizeof(vmst->hdr.magic)) != 0) {
101 _kvm_err(kd, kd->program, "not a minidump for this platform");
102 return (-1);
103 }
104
105 vmst->hdr.version = le32toh(vmst->hdr.version);
106 if (vmst->hdr.version > MINIDUMP_VERSION || vmst->hdr.version < 1) {
107 _kvm_err(kd, kd->program, "wrong minidump version. "
108 "Expected %d got %d", MINIDUMP_VERSION, vmst->hdr.version);
109 return (-1);
110 }
111 vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize);
112 vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize);
113 vmst->hdr.pmapsize = le32toh(vmst->hdr.pmapsize);
114 vmst->hdr.kernbase = le64toh(vmst->hdr.kernbase);
115 vmst->hdr.dmapphys = le64toh(vmst->hdr.dmapphys);
116 vmst->hdr.dmapbase = le64toh(vmst->hdr.dmapbase);
117 vmst->hdr.dmapend = le64toh(vmst->hdr.dmapend);
118 /* dumpavailsize added in version 2 */
119 if (vmst->hdr.version >= 2) {
120 vmst->hdr.dumpavailsize = le32toh(vmst->hdr.dumpavailsize);
121 } else {
122 vmst->hdr.dumpavailsize = 0;
123 }
124 /* flags added in version 3 */
125 if (vmst->hdr.version >= 3) {
126 vmst->hdr.flags = le32toh(vmst->hdr.flags);
127 } else {
128 vmst->hdr.flags = MINIDUMP_FLAG_PS_4K;
129 }
130
131 switch (vmst->hdr.flags & MINIDUMP_FLAG_PS_MASK) {
132 case MINIDUMP_FLAG_PS_4K:
133 vmst->page_size = AARCH64_PAGE_SIZE_4K;
134 vmst->l3_shift = AARCH64_L3_SHIFT_4K;
135 break;
136 case MINIDUMP_FLAG_PS_16K:
137 vmst->page_size = AARCH64_PAGE_SIZE_16K;
138 vmst->l3_shift = AARCH64_L3_SHIFT_16K;
139 break;
140 default:
141 _kvm_err(kd, kd->program, "unknown page size flag %x",
142 vmst->hdr.flags & MINIDUMP_FLAG_PS_MASK);
143 return (-1);
144 }
145
146 /* Skip header and msgbuf */
147 dump_avail_off = vmst->page_size +
148 aarch64_round_page(vmst->hdr.msgbufsize, vmst->page_size);
149
150 /* Skip dump_avail */
151 off = dump_avail_off +
152 aarch64_round_page(vmst->hdr.dumpavailsize, vmst->page_size);
153
154 /* build physical address lookup table for sparse pages */
155 sparse_off = off +
156 aarch64_round_page(vmst->hdr.bitmapsize, vmst->page_size) +
157 aarch64_round_page(vmst->hdr.pmapsize, vmst->page_size);
158 if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
159 vmst->hdr.bitmapsize, off, sparse_off, vmst->page_size) == -1) {
160 return (-1);
161 }
162 off += aarch64_round_page(vmst->hdr.bitmapsize, vmst->page_size);
163
164 if (_kvm_pmap_init(kd, vmst->hdr.pmapsize, off) == -1) {
165 return (-1);
166 }
167 off += aarch64_round_page(vmst->hdr.pmapsize, vmst->page_size);
168
169 return (0);
170 }
171
172 static int
_aarch64_minidump_vatop(kvm_t * kd,kvaddr_t va,off_t * pa)173 _aarch64_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
174 {
175 struct vmstate *vm;
176 aarch64_physaddr_t offset;
177 aarch64_pte_t l3;
178 kvaddr_t l3_index;
179 aarch64_physaddr_t a;
180 off_t ofs;
181
182 vm = kd->vmst;
183 offset = va & (kd->vmst->page_size - 1);
184
185 if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
186 a = aarch64_trunc_page(va - vm->hdr.dmapbase + vm->hdr.dmapphys,
187 kd->vmst->page_size);
188 ofs = _kvm_pt_find(kd, a, kd->vmst->page_size);
189 if (ofs == -1) {
190 _kvm_err(kd, kd->program, "_aarch64_minidump_vatop: "
191 "direct map address 0x%jx not in minidump",
192 (uintmax_t)va);
193 goto invalid;
194 }
195 *pa = ofs + offset;
196 return (kd->vmst->page_size - offset);
197 } else if (va >= vm->hdr.kernbase) {
198 l3_index = (va - vm->hdr.kernbase) >> kd->vmst->l3_shift;
199 if (l3_index >= vm->hdr.pmapsize / sizeof(l3))
200 goto invalid;
201 l3 = _aarch64_pte_get(kd, l3_index);
202 if ((l3 & AARCH64_ATTR_DESCR_MASK) != AARCH64_L3_PAGE) {
203 _kvm_err(kd, kd->program,
204 "_aarch64_minidump_vatop: pde not valid");
205 goto invalid;
206 }
207 a = l3 & ~AARCH64_ATTR_MASK;
208 ofs = _kvm_pt_find(kd, a, kd->vmst->page_size);
209 if (ofs == -1) {
210 _kvm_err(kd, kd->program, "_aarch64_minidump_vatop: "
211 "physical address 0x%jx not in minidump",
212 (uintmax_t)a);
213 goto invalid;
214 }
215 *pa = ofs + offset;
216 return (kd->vmst->page_size - offset);
217 } else {
218 _kvm_err(kd, kd->program,
219 "_aarch64_minidump_vatop: virtual address 0x%jx not minidumped",
220 (uintmax_t)va);
221 goto invalid;
222 }
223
224 invalid:
225 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
226 return (0);
227 }
228
229 static int
_aarch64_minidump_kvatop(kvm_t * kd,kvaddr_t va,off_t * pa)230 _aarch64_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
231 {
232
233 if (ISALIVE(kd)) {
234 _kvm_err(kd, 0,
235 "_aarch64_minidump_kvatop called in live kernel!");
236 return (0);
237 }
238 return (_aarch64_minidump_vatop(kd, va, pa));
239 }
240
241 static int
_aarch64_native(kvm_t * kd __unused)242 _aarch64_native(kvm_t *kd __unused)
243 {
244
245 #ifdef __aarch64__
246 return (1);
247 #else
248 return (0);
249 #endif
250 }
251
252 static vm_prot_t
_aarch64_entry_to_prot(aarch64_pte_t pte)253 _aarch64_entry_to_prot(aarch64_pte_t pte)
254 {
255 vm_prot_t prot = VM_PROT_READ;
256
257 /* Source: arm64/arm64/pmap.c:pmap_protect() */
258 if ((pte & AARCH64_ATTR_AP(AARCH64_ATTR_AP_RO)) == 0)
259 prot |= VM_PROT_WRITE;
260 if ((pte & AARCH64_ATTR_XN) == 0)
261 prot |= VM_PROT_EXECUTE;
262 return prot;
263 }
264
265 static int
_aarch64_minidump_walk_pages(kvm_t * kd,kvm_walk_pages_cb_t * cb,void * arg)266 _aarch64_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg)
267 {
268 struct vmstate *vm = kd->vmst;
269 u_long nptes = vm->hdr.pmapsize / sizeof(aarch64_pte_t);
270 u_long bmindex, dva, pa, pteindex, va;
271 struct kvm_bitmap bm;
272 vm_prot_t prot;
273 int ret = 0;
274
275 if (!_kvm_bitmap_init(&bm, vm->hdr.bitmapsize, &bmindex))
276 return (0);
277
278 for (pteindex = 0; pteindex < nptes; pteindex++) {
279 aarch64_pte_t pte = _aarch64_pte_get(kd, pteindex);
280
281 if ((pte & AARCH64_ATTR_DESCR_MASK) != AARCH64_L3_PAGE)
282 continue;
283
284 va = vm->hdr.kernbase + (pteindex << kd->vmst->l3_shift);
285 pa = pte & ~AARCH64_ATTR_MASK;
286 dva = vm->hdr.dmapbase + pa;
287 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
288 _aarch64_entry_to_prot(pte), kd->vmst->page_size, 0)) {
289 goto out;
290 }
291 }
292
293 while (_kvm_bitmap_next(&bm, &bmindex)) {
294 pa = _kvm_bit_id_pa(kd, bmindex, kd->vmst->page_size);
295 if (pa == _KVM_PA_INVALID)
296 break;
297 dva = vm->hdr.dmapbase + pa;
298 if (vm->hdr.dmapend < (dva + kd->vmst->page_size))
299 break;
300 va = 0;
301 prot = VM_PROT_READ | VM_PROT_WRITE;
302 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
303 prot, kd->vmst->page_size, 0)) {
304 goto out;
305 }
306 }
307 ret = 1;
308
309 out:
310 _kvm_bitmap_deinit(&bm);
311 return (ret);
312 }
313
314 static struct kvm_arch kvm_aarch64_minidump = {
315 .ka_probe = _aarch64_minidump_probe,
316 .ka_initvtop = _aarch64_minidump_initvtop,
317 .ka_freevtop = _aarch64_minidump_freevtop,
318 .ka_kvatop = _aarch64_minidump_kvatop,
319 .ka_native = _aarch64_native,
320 .ka_walk_pages = _aarch64_minidump_walk_pages,
321 };
322
323 KVM_ARCH(kvm_aarch64_minidump);
324