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
39static 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
72void
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*/
82int
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 */
92int
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
189struct p2o {
190	paddr_t pa;
191	psize_t sz;
192	off_t off;
193};
194
195static int
196cmp_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 */
222off_t
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 */
268int
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