1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2008 Semihalf, Grzegorz Bernacki
5 * Copyright (c) 2006 Peter Wemm
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * From: FreeBSD: src/lib/libkvm/kvm_minidump_i386.c,v 1.2 2006/06/05 08:51:14
29 */
30
31 #include <sys/cdefs.h>
32 /*
33 * ARM machine dependent routines for kvm and minidumps.
34 */
35
36 #include <sys/endian.h>
37 #include <sys/param.h>
38 #include <vm/vm.h>
39 #include <kvm.h>
40 #include <limits.h>
41 #include <stdint.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45
46 #include "../../sys/arm/include/minidump.h"
47
48 #include "kvm_private.h"
49 #include "kvm_arm.h"
50
51 #define arm_round_page(x) roundup2((kvaddr_t)(x), ARM_PAGE_SIZE)
52
53 struct vmstate {
54 struct minidumphdr hdr;
55 unsigned char ei_data;
56 };
57
58 static arm_pt_entry_t
_arm_pte_get(kvm_t * kd,u_long pteindex)59 _arm_pte_get(kvm_t *kd, u_long pteindex)
60 {
61 arm_pt_entry_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte));
62
63 return _kvm32toh(kd, *pte);
64 }
65
66 static int
_arm_minidump_probe(kvm_t * kd)67 _arm_minidump_probe(kvm_t *kd)
68 {
69
70 return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_ARM) &&
71 _kvm_is_minidump(kd));
72 }
73
74 static void
_arm_minidump_freevtop(kvm_t * kd)75 _arm_minidump_freevtop(kvm_t *kd)
76 {
77 struct vmstate *vm = kd->vmst;
78
79 free(vm);
80 kd->vmst = NULL;
81 }
82
83 static int
_arm_minidump_initvtop(kvm_t * kd)84 _arm_minidump_initvtop(kvm_t *kd)
85 {
86 struct vmstate *vmst;
87 off_t off, dump_avail_off, sparse_off;
88
89 vmst = _kvm_malloc(kd, sizeof(*vmst));
90 if (vmst == NULL) {
91 _kvm_err(kd, kd->program, "cannot allocate vm");
92 return (-1);
93 }
94
95 kd->vmst = vmst;
96
97 if (pread(kd->pmfd, &vmst->hdr,
98 sizeof(vmst->hdr), 0) != sizeof(vmst->hdr)) {
99 _kvm_err(kd, kd->program, "cannot read dump header");
100 return (-1);
101 }
102
103 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
104 sizeof(vmst->hdr.magic)) != 0) {
105 _kvm_err(kd, kd->program, "not a minidump for this platform");
106 return (-1);
107 }
108 vmst->hdr.version = _kvm32toh(kd, vmst->hdr.version);
109 if (vmst->hdr.version != MINIDUMP_VERSION && vmst->hdr.version != 1) {
110 _kvm_err(kd, kd->program, "wrong minidump version. "
111 "Expected %d got %d", MINIDUMP_VERSION, vmst->hdr.version);
112 return (-1);
113 }
114 vmst->hdr.msgbufsize = _kvm32toh(kd, vmst->hdr.msgbufsize);
115 vmst->hdr.bitmapsize = _kvm32toh(kd, vmst->hdr.bitmapsize);
116 vmst->hdr.ptesize = _kvm32toh(kd, vmst->hdr.ptesize);
117 vmst->hdr.kernbase = _kvm32toh(kd, vmst->hdr.kernbase);
118 vmst->hdr.arch = _kvm32toh(kd, vmst->hdr.arch);
119 vmst->hdr.mmuformat = _kvm32toh(kd, vmst->hdr.mmuformat);
120 if (vmst->hdr.mmuformat == MINIDUMP_MMU_FORMAT_UNKNOWN) {
121 /* This is a safe default as 1K pages are not used. */
122 vmst->hdr.mmuformat = MINIDUMP_MMU_FORMAT_V6;
123 }
124 vmst->hdr.dumpavailsize = vmst->hdr.version == MINIDUMP_VERSION ?
125 _kvm32toh(kd, vmst->hdr.dumpavailsize) : 0;
126
127 /* Skip header and msgbuf */
128 dump_avail_off = ARM_PAGE_SIZE + arm_round_page(vmst->hdr.msgbufsize);
129
130 /* Skip dump_avail */
131 off = dump_avail_off + arm_round_page(vmst->hdr.dumpavailsize);
132
133 sparse_off = off + arm_round_page(vmst->hdr.bitmapsize) +
134 arm_round_page(vmst->hdr.ptesize);
135 if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
136 vmst->hdr.bitmapsize, off, sparse_off, ARM_PAGE_SIZE) == -1) {
137 return (-1);
138 }
139 off += arm_round_page(vmst->hdr.bitmapsize);
140
141 if (_kvm_pmap_init(kd, vmst->hdr.ptesize, off) == -1) {
142 return (-1);
143 }
144 off += arm_round_page(vmst->hdr.ptesize);
145
146 return (0);
147 }
148
149 static int
_arm_minidump_kvatop(kvm_t * kd,kvaddr_t va,off_t * pa)150 _arm_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
151 {
152 struct vmstate *vm;
153 arm_pt_entry_t pte;
154 arm_physaddr_t offset, a;
155 kvaddr_t pteindex;
156 off_t ofs;
157
158 if (ISALIVE(kd)) {
159 _kvm_err(kd, 0, "_arm_minidump_kvatop called in live kernel!");
160 return (0);
161 }
162
163 vm = kd->vmst;
164
165 if (va >= vm->hdr.kernbase) {
166 pteindex = (va - vm->hdr.kernbase) >> ARM_PAGE_SHIFT;
167 if (pteindex >= vm->hdr.ptesize / sizeof(pte))
168 goto invalid;
169 pte = _arm_pte_get(kd, pteindex);
170 if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_INV) {
171 _kvm_err(kd, kd->program,
172 "_arm_minidump_kvatop: pte not valid");
173 goto invalid;
174 }
175 if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_L) {
176 /* 64K page -> convert to be like 4K page */
177 offset = va & ARM_L2_S_OFFSET;
178 a = (pte & ARM_L2_L_FRAME) +
179 (va & ARM_L2_L_OFFSET & ARM_L2_S_FRAME);
180 } else {
181 if (kd->vmst->hdr.mmuformat == MINIDUMP_MMU_FORMAT_V4 &&
182 (pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_T) {
183 _kvm_err(kd, kd->program,
184 "_arm_minidump_kvatop: pte not supported");
185 goto invalid;
186 }
187 /* 4K page */
188 offset = va & ARM_L2_S_OFFSET;
189 a = pte & ARM_L2_S_FRAME;
190 }
191
192 ofs = _kvm_pt_find(kd, a, ARM_PAGE_SIZE);
193 if (ofs == -1) {
194 _kvm_err(kd, kd->program, "_arm_minidump_kvatop: "
195 "physical address 0x%jx not in minidump",
196 (uintmax_t)a);
197 goto invalid;
198 }
199
200 *pa = ofs + offset;
201 return (ARM_PAGE_SIZE - offset);
202 } else
203 _kvm_err(kd, kd->program, "_arm_minidump_kvatop: virtual "
204 "address 0x%jx not minidumped", (uintmax_t)va);
205
206 invalid:
207 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
208 return (0);
209 }
210
211 static vm_prot_t
_arm_entry_to_prot(kvm_t * kd,arm_pt_entry_t pte)212 _arm_entry_to_prot(kvm_t *kd, arm_pt_entry_t pte)
213 {
214 struct vmstate *vm = kd->vmst;
215 vm_prot_t prot = VM_PROT_READ;
216
217 /* Source: arm/arm/pmap-v4.c:pmap_fault_fixup() */
218 if (vm->hdr.mmuformat == MINIDUMP_MMU_FORMAT_V4) {
219 if (pte & ARM_L2_S_PROT_W)
220 prot |= VM_PROT_WRITE;
221 return prot;
222 }
223
224 /* Source: arm/arm/pmap-v6.c:pmap_protect() */
225 if ((pte & ARM_PTE2_RO) == 0)
226 prot |= VM_PROT_WRITE;
227 if ((pte & ARM_PTE2_NX) == 0)
228 prot |= VM_PROT_EXECUTE;
229 return prot;
230 }
231
232 static int
_arm_minidump_walk_pages(kvm_t * kd,kvm_walk_pages_cb_t * cb,void * arg)233 _arm_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg)
234 {
235 struct vmstate *vm = kd->vmst;
236 u_long nptes = vm->hdr.ptesize / sizeof(arm_pt_entry_t);
237 u_long dva, pa, pteindex, va;
238
239 for (pteindex = 0; pteindex < nptes; pteindex++) {
240 arm_pt_entry_t pte = _arm_pte_get(kd, pteindex);
241
242 if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_INV)
243 continue;
244
245 va = vm->hdr.kernbase + (pteindex << ARM_PAGE_SHIFT);
246 if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_L) {
247 /* 64K page */
248 pa = (pte & ARM_L2_L_FRAME) +
249 (va & ARM_L2_L_OFFSET & ARM_L2_S_FRAME);
250 } else {
251 if (vm->hdr.mmuformat == MINIDUMP_MMU_FORMAT_V4 &&
252 (pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_T) {
253 continue;
254 }
255 /* 4K page */
256 pa = pte & ARM_L2_S_FRAME;
257 }
258
259 dva = 0; /* no direct map on this platform */
260 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
261 _arm_entry_to_prot(kd, pte), ARM_PAGE_SIZE, 0))
262 return (0);
263 }
264 return (1);
265 }
266
267 static struct kvm_arch kvm_arm_minidump = {
268 .ka_probe = _arm_minidump_probe,
269 .ka_initvtop = _arm_minidump_initvtop,
270 .ka_freevtop = _arm_minidump_freevtop,
271 .ka_kvatop = _arm_minidump_kvatop,
272 .ka_native = _arm_native,
273 .ka_walk_pages = _arm_minidump_walk_pages,
274 };
275
276 KVM_ARCH(kvm_arm_minidump);
277