1 /* $NetBSD: kvm_x86_64.c,v 1.13 2022/01/10 19:51:30 christos Exp $ */
2
3 /*-
4 * Copyright (c) 1989, 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software developed by the Computer Systems
8 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
9 * BG 91-66 and contributed to Berkeley.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <sys/cdefs.h>
37 #if defined(LIBC_SCCS) && !defined(lint)
38 #if 0
39 static char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93";
40 #else
41 __RCSID("$NetBSD: kvm_x86_64.c,v 1.13 2022/01/10 19:51:30 christos Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44
45 /*
46 * x86-64 machine dependent routines for kvm.
47 */
48
49 #include <sys/param.h>
50 #include <sys/proc.h>
51 #include <sys/stat.h>
52 #include <sys/kcore.h>
53 #include <sys/types.h>
54
55 #include <stdlib.h>
56 #include <unistd.h>
57 #include <nlist.h>
58 #include <kvm.h>
59
60 #include <uvm/uvm_extern.h>
61
62 #include <limits.h>
63 #include <db.h>
64
65 #include "kvm_private.h"
66
67 #include <machine/kcore.h>
68 #include <machine/pmap.h>
69 #include <machine/pte.h>
70 #include <machine/vmparam.h>
71
72 void
_kvm_freevtop(kvm_t * kd)73 _kvm_freevtop(kvm_t *kd)
74 {
75
76 /* Not actually used for anything right now, but safe. */
77 if (kd->vmst != 0)
78 free(kd->vmst);
79 }
80
81 /*ARGSUSED*/
82 int
_kvm_initvtop(kvm_t * kd)83 _kvm_initvtop(kvm_t *kd)
84 {
85
86 return (0);
87 }
88
89 /*
90 * Translate a kernel virtual address to a physical address.
91 */
92 int
_kvm_kvatop(kvm_t * kd,vaddr_t va,paddr_t * pa)93 _kvm_kvatop(kvm_t *kd, vaddr_t va, paddr_t *pa)
94 {
95 cpu_kcore_hdr_t *cpu_kh;
96 u_long page_off;
97 pd_entry_t pde;
98 pt_entry_t pte;
99 paddr_t pde_pa, pte_pa;
100
101 if (ISALIVE(kd)) {
102 _kvm_err(kd, 0, "vatop called in live kernel!");
103 return (0);
104 }
105
106 cpu_kh = kd->cpu_data;
107
108 /*
109 * Find and read all entries to get to the pa.
110 */
111
112 /*
113 * Level 4.
114 */
115 pde_pa = cpu_kh->ptdpaddr + (pl4_pi(va) * sizeof(pd_entry_t));
116 if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
117 _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
118 _kvm_syserr(kd, 0, "could not read PT level 4 entry");
119 goto lose;
120 }
121 if ((pde & PTE_P) == 0) {
122 _kvm_err(kd, 0, "invalid translation (invalid level 4 PDE)");
123 goto lose;
124 }
125
126 /*
127 * Level 3.
128 */
129 pde_pa = (pde & PTE_FRAME) + (pl3_pi(va) * sizeof(pd_entry_t));
130 if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
131 _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
132 _kvm_syserr(kd, 0, "could not read PT level 3 entry");
133 goto lose;
134 }
135 if ((pde & PTE_P) == 0) {
136 _kvm_err(kd, 0, "invalid translation (invalid level 3 PDE)");
137 goto lose;
138 }
139 if (pde & PTE_PS) {
140 page_off = va & (NBPD_L3 - 1);
141 *pa = (pde & PTE_1GFRAME) + page_off;
142 return (int)(NBPD_L3 - page_off);
143 }
144
145 /*
146 * Level 2.
147 */
148 pde_pa = (pde & PTE_FRAME) + (pl2_pi(va) * sizeof(pd_entry_t));
149 if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
150 _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
151 _kvm_syserr(kd, 0, "could not read PT level 2 entry");
152 goto lose;
153 }
154 if ((pde & PTE_P) == 0) {
155 _kvm_err(kd, 0, "invalid translation (invalid level 2 PDE)");
156 goto lose;
157 }
158 if (pde & PTE_PS) {
159 page_off = va & (NBPD_L2 - 1);
160 *pa = (pde & PTE_2MFRAME) + page_off;
161 return (int)(NBPD_L2 - page_off);
162 }
163
164 /*
165 * Level 1.
166 */
167 pte_pa = (pde & PTE_FRAME) + (pl1_pi(va) * sizeof(pt_entry_t));
168 if (_kvm_pread(kd, kd->pmfd, (void *) &pte, sizeof(pte),
169 _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
170 _kvm_syserr(kd, 0, "could not read PTE");
171 goto lose;
172 }
173 /*
174 * Validate the PTE and return the physical address.
175 */
176 if ((pte & PTE_P) == 0) {
177 _kvm_err(kd, 0, "invalid translation (invalid PTE)");
178 goto lose;
179 }
180 page_off = va & PGOFSET;
181 *pa = (pte & PTE_FRAME) + page_off;
182 return (int)(NBPG - page_off);
183
184 lose:
185 *pa = (u_long)~0L;
186 return (0);
187 }
188
189 struct p2o {
190 paddr_t pa;
191 psize_t sz;
192 off_t off;
193 };
194
195 static int
cmp_p2o(const void * a,const void * b)196 cmp_p2o(const void *a, const void *b)
197 {
198 const struct p2o *p1 = a;
199 const struct p2o *p2 = b;
200
201 /* If one range contains the start of the other, it's a match. */
202 if (p1->pa >= p2->pa && p1->pa < p2->pa + p2->sz) {
203 return 0;
204 }
205 if (p2->pa >= p1->pa && p2->pa < p1->pa + p1->sz) {
206 return 0;
207 }
208
209 /* Otherwise sort by pa. */
210 if (p1->pa < p2->pa)
211 return -1;
212 else if (p1->pa > p2->pa)
213 return 1;
214 else
215 return 0;
216 }
217
218
219 /*
220 * Translate a physical address to a file-offset in the crash dump.
221 */
222 off_t
_kvm_pa2off(kvm_t * kd,paddr_t pa)223 _kvm_pa2off(kvm_t *kd, paddr_t pa)
224 {
225 cpu_kcore_hdr_t *cpu_kh;
226 phys_ram_seg_t *ramsegs;
227 off_t off;
228 int i;
229
230 static struct p2o *map;
231 struct p2o key, *val;
232
233 cpu_kh = kd->cpu_data;
234 ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh));
235
236 if (map == NULL) {
237 map = calloc(sizeof *map, cpu_kh->nmemsegs);
238 off = 0;
239 for (i = 0; i < cpu_kh->nmemsegs; i++) {
240 map[i].pa = ramsegs[i].start;
241 map[i].sz = ramsegs[i].size;
242 map[i].off = off;
243 off += ramsegs[i].size;
244 }
245 #if 0
246 /* The array appears to be sorted already */
247 qsort(map, cpu_kh->nmemsegs, sizeof(*map), cmp_p2o);
248 #endif
249 }
250
251 key.pa = pa;
252 key.sz = 1;
253 key.off = -1;
254 val = bsearch(&key, map, cpu_kh->nmemsegs, sizeof (key), cmp_p2o);
255 if (val)
256 off = val->off + pa - val->pa;
257 else
258 off = 0;
259
260 return (kd->dump_off + off);
261 }
262
263 /*
264 * Machine-dependent initialization for ALL open kvm descriptors,
265 * not just those for a kernel crash dump. Some architectures
266 * have to deal with these NOT being constants! (i.e. m68k)
267 */
268 int
_kvm_mdopen(kvm_t * kd)269 _kvm_mdopen(kvm_t *kd)
270 {
271
272 kd->min_uva = VM_MIN_ADDRESS;
273 kd->max_uva = VM_MAXUSER_ADDRESS;
274
275 return (0);
276 }
277