xref: /minix3/lib/libkvm/kvm_x86_64.c (revision 9da227510d14c35cccbd92c6a9e316b4079c4911)
1 /*	$NetBSD: kvm_x86_64.c,v 1.10 2014/02/19 20:21:22 dsl 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 1.10 2014/02/19 20:21:22 dsl 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 & PG_V) == 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 & PG_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 & PG_V) == 0) {
136 		_kvm_err(kd, 0, "invalid translation (invalid level 3 PDE)");
137 		goto lose;
138 	}
139 	if (pde & PG_PS) {
140 		page_off = va & (NBPD_L3 - 1);
141 		*pa = (pde & PG_1GFRAME) + page_off;
142 		return (int)(NBPD_L3 - page_off);
143 	}
144 
145 	/*
146 	 * Level 2.
147 	 */
148 	pde_pa = (pde & PG_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 & PG_V) == 0) {
155 		_kvm_err(kd, 0, "invalid translation (invalid level 2 PDE)");
156 		goto lose;
157 	}
158 	if (pde & PG_PS) {
159 		page_off = va & (NBPD_L2 - 1);
160 		*pa = (pde & PG_2MFRAME) + page_off;
161 		return (int)(NBPD_L2 - page_off);
162 	}
163 
164 	/*
165 	 * Level 1.
166 	 */
167 	pte_pa = (pde & PG_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 & PG_V) == 0) {
177 		_kvm_err(kd, 0, "invalid translation (invalid PTE)");
178 		goto lose;
179 	}
180 	page_off = va & PGOFSET;
181 	*pa = (pte & PG_FRAME) + page_off;
182 	return (int)(NBPG - page_off);
183 
184  lose:
185 	*pa = (u_long)~0L;
186 	return (0);
187 }
188 
189 /*
190  * Translate a physical address to a file-offset in the crash dump.
191  */
192 off_t
_kvm_pa2off(kvm_t * kd,paddr_t pa)193 _kvm_pa2off(kvm_t *kd, paddr_t pa)
194 {
195 	cpu_kcore_hdr_t *cpu_kh;
196 	phys_ram_seg_t *ramsegs;
197 	off_t off;
198 	int i;
199 
200 	cpu_kh = kd->cpu_data;
201 	ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh));
202 
203 	off = 0;
204 	for (i = 0; i < cpu_kh->nmemsegs; i++) {
205 		if (pa >= ramsegs[i].start &&
206 		    (pa - ramsegs[i].start) < ramsegs[i].size) {
207 			off += (pa - ramsegs[i].start);
208 			break;
209 		}
210 		off += ramsegs[i].size;
211 	}
212 
213 	return (kd->dump_off + off);
214 }
215 
216 /*
217  * Machine-dependent initialization for ALL open kvm descriptors,
218  * not just those for a kernel crash dump.  Some architectures
219  * have to deal with these NOT being constants!  (i.e. m68k)
220  */
221 int
_kvm_mdopen(kvm_t * kd)222 _kvm_mdopen(kvm_t *kd)
223 {
224 
225 	kd->usrstack = USRSTACK;
226 	kd->min_uva = VM_MIN_ADDRESS;
227 	kd->max_uva = VM_MAXUSER_ADDRESS;
228 
229 	return (0);
230 }
231