1 /*-
2 * Copyright (c) 2006 Peter Wemm
3 * Copyright (c) 2019 Mitchell Horne
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * From: FreeBSD: src/lib/libkvm/kvm_minidump_amd64.c r261799
27 */
28
29 #include <sys/cdefs.h>
30 /*
31 * RISC-V machine dependent routines for kvm and minidumps.
32 */
33
34 #include <sys/param.h>
35 #include <stdint.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 #include <vm/vm.h>
40 #include <kvm.h>
41
42 #include "../../sys/riscv/include/minidump.h"
43
44 #include <limits.h>
45
46 #include "kvm_private.h"
47 #include "kvm_riscv.h"
48
49 #define riscv_round_page(x) roundup2((kvaddr_t)(x), RISCV_PAGE_SIZE)
50
51 struct vmstate {
52 struct minidumphdr hdr;
53 };
54
55 static riscv_pt_entry_t
_riscv_pte_get(kvm_t * kd,u_long pteindex)56 _riscv_pte_get(kvm_t *kd, u_long pteindex)
57 {
58 riscv_pt_entry_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte));
59
60 return le64toh(*pte);
61 }
62
63 static int
_riscv_minidump_probe(kvm_t * kd)64 _riscv_minidump_probe(kvm_t *kd)
65 {
66
67 return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_RISCV) &&
68 _kvm_is_minidump(kd));
69 }
70
71 static void
_riscv_minidump_freevtop(kvm_t * kd)72 _riscv_minidump_freevtop(kvm_t *kd)
73 {
74 struct vmstate *vm = kd->vmst;
75
76 free(vm);
77 kd->vmst = NULL;
78 }
79
80 static int
_riscv_minidump_initvtop(kvm_t * kd)81 _riscv_minidump_initvtop(kvm_t *kd)
82 {
83 struct vmstate *vmst;
84 off_t off, dump_avail_off, sparse_off;
85
86 vmst = _kvm_malloc(kd, sizeof(*vmst));
87 if (vmst == NULL) {
88 _kvm_err(kd, kd->program, "cannot allocate vm");
89 return (-1);
90 }
91 kd->vmst = vmst;
92 if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
93 sizeof(vmst->hdr)) {
94 _kvm_err(kd, kd->program, "cannot read dump header");
95 return (-1);
96 }
97 if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
98 sizeof(vmst->hdr.magic)) != 0) {
99 _kvm_err(kd, kd->program, "not a minidump for this platform");
100 return (-1);
101 }
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. "
106 "Expected %d got %d", 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.dmapphys = le64toh(vmst->hdr.dmapphys);
114 vmst->hdr.dmapbase = le64toh(vmst->hdr.dmapbase);
115 vmst->hdr.dmapend = le64toh(vmst->hdr.dmapend);
116 vmst->hdr.dumpavailsize = vmst->hdr.version == MINIDUMP_VERSION ?
117 le32toh(vmst->hdr.dumpavailsize) : 0;
118
119 /* Skip header and msgbuf */
120 dump_avail_off = RISCV_PAGE_SIZE + riscv_round_page(vmst->hdr.msgbufsize);
121
122 /* Skip dump_avail */
123 off = dump_avail_off + riscv_round_page(vmst->hdr.dumpavailsize);
124
125 /* build physical address lookup table for sparse pages */
126 sparse_off = off + riscv_round_page(vmst->hdr.bitmapsize) +
127 riscv_round_page(vmst->hdr.pmapsize);
128 if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
129 vmst->hdr.bitmapsize, off, sparse_off, RISCV_PAGE_SIZE) == -1) {
130 return (-1);
131 }
132 off += riscv_round_page(vmst->hdr.bitmapsize);
133
134 if (_kvm_pmap_init(kd, vmst->hdr.pmapsize, off) == -1) {
135 return (-1);
136 }
137 off += riscv_round_page(vmst->hdr.pmapsize);
138
139 return (0);
140 }
141
142 static int
_riscv_minidump_vatop(kvm_t * kd,kvaddr_t va,off_t * pa)143 _riscv_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
144 {
145 struct vmstate *vm;
146 riscv_physaddr_t offset;
147 riscv_pt_entry_t l3;
148 kvaddr_t l3_index;
149 riscv_physaddr_t a;
150 off_t ofs;
151
152 vm = kd->vmst;
153 offset = va & RISCV_PAGE_MASK;
154
155 if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
156 a = (va - vm->hdr.dmapbase + vm->hdr.dmapphys) &
157 ~RISCV_PAGE_MASK;
158 ofs = _kvm_pt_find(kd, a, RISCV_PAGE_SIZE);
159 if (ofs == -1) {
160 _kvm_err(kd, kd->program, "_riscv_minidump_vatop: "
161 "direct map address 0x%jx not in minidump",
162 (uintmax_t)va);
163 goto invalid;
164 }
165 *pa = ofs + offset;
166 return (RISCV_PAGE_SIZE - offset);
167 } else if (va >= vm->hdr.kernbase) {
168 l3_index = (va - vm->hdr.kernbase) >> RISCV_L3_SHIFT;
169 if (l3_index >= vm->hdr.pmapsize / sizeof(l3))
170 goto invalid;
171 l3 = _riscv_pte_get(kd, l3_index);
172 if ((l3 & RISCV_PTE_V) == 0 || (l3 & RISCV_PTE_RWX) == 0) {
173 _kvm_err(kd, kd->program,
174 "_riscv_minidump_vatop: pte not valid");
175 goto invalid;
176 }
177 a = (l3 >> RISCV_PTE_PPN0_S) << RISCV_L3_SHIFT;
178 ofs = _kvm_pt_find(kd, a, RISCV_PAGE_SIZE);
179 if (ofs == -1) {
180 _kvm_err(kd, kd->program, "_riscv_minidump_vatop: "
181 "physical address 0x%jx not in minidump",
182 (uintmax_t)a);
183 goto invalid;
184 }
185 *pa = ofs + offset;
186 return (RISCV_PAGE_SIZE - offset);
187 } else {
188 _kvm_err(kd, kd->program,
189 "_riscv_minidump_vatop: virtual address 0x%jx not minidumped",
190 (uintmax_t)va);
191 goto invalid;
192 }
193
194 invalid:
195 _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
196 return (0);
197 }
198
199 static int
_riscv_minidump_kvatop(kvm_t * kd,kvaddr_t va,off_t * pa)200 _riscv_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
201 {
202
203 if (ISALIVE(kd)) {
204 _kvm_err(kd, 0,
205 "_riscv_minidump_kvatop called in live kernel!");
206 return (0);
207 }
208 return (_riscv_minidump_vatop(kd, va, pa));
209 }
210
211 static int
_riscv_native(kvm_t * kd __unused)212 _riscv_native(kvm_t *kd __unused)
213 {
214
215 #ifdef __riscv
216 return (1);
217 #else
218 return (0);
219 #endif
220 }
221
222 static vm_prot_t
_riscv_entry_to_prot(riscv_pt_entry_t pte)223 _riscv_entry_to_prot(riscv_pt_entry_t pte)
224 {
225 vm_prot_t prot = VM_PROT_READ;
226
227 if ((pte & RISCV_PTE_W) != 0)
228 prot |= VM_PROT_WRITE;
229 if ((pte & RISCV_PTE_X) != 0)
230 prot |= VM_PROT_EXECUTE;
231 return prot;
232 }
233
234 static int
_riscv_minidump_walk_pages(kvm_t * kd,kvm_walk_pages_cb_t * cb,void * arg)235 _riscv_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg)
236 {
237 struct vmstate *vm = kd->vmst;
238 u_long nptes = vm->hdr.pmapsize / sizeof(riscv_pt_entry_t);
239 u_long bmindex, dva, pa, pteindex, va;
240 struct kvm_bitmap bm;
241 vm_prot_t prot;
242 int ret = 0;
243
244 if (!_kvm_bitmap_init(&bm, vm->hdr.bitmapsize, &bmindex))
245 return (0);
246
247 for (pteindex = 0; pteindex < nptes; pteindex++) {
248 riscv_pt_entry_t pte = _riscv_pte_get(kd, pteindex);
249
250 if (((pte & RISCV_PTE_V) == 0) ||
251 ((pte & RISCV_PTE_RWX) == 0))
252 continue;
253
254 va = vm->hdr.kernbase + (pteindex << RISCV_L3_SHIFT);
255 pa = (pte >> RISCV_PTE_PPN0_S) << RISCV_L3_SHIFT;
256 dva = vm->hdr.dmapbase + pa;
257 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
258 _riscv_entry_to_prot(pte), RISCV_PAGE_SIZE, 0)) {
259 goto out;
260 }
261 }
262
263 while (_kvm_bitmap_next(&bm, &bmindex)) {
264 pa = _kvm_bit_id_pa(kd, bmindex, RISCV_PAGE_SIZE);
265 if (pa == _KVM_PA_INVALID)
266 break;
267 dva = vm->hdr.dmapbase + pa;
268 if (vm->hdr.dmapend < (dva + RISCV_PAGE_SIZE))
269 break;
270 va = 0;
271 prot = VM_PROT_READ | VM_PROT_WRITE;
272 if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
273 prot, RISCV_PAGE_SIZE, 0)) {
274 goto out;
275 }
276 }
277 ret = 1;
278
279 out:
280 _kvm_bitmap_deinit(&bm);
281 return (ret);
282 }
283
284 static struct kvm_arch kvm_riscv_minidump = {
285 .ka_probe = _riscv_minidump_probe,
286 .ka_initvtop = _riscv_minidump_initvtop,
287 .ka_freevtop = _riscv_minidump_freevtop,
288 .ka_kvatop = _riscv_minidump_kvatop,
289 .ka_native = _riscv_native,
290 .ka_walk_pages = _riscv_minidump_walk_pages,
291 };
292
293 KVM_ARCH(kvm_riscv_minidump);
294