xref: /netbsd-src/lib/libkvm/kvm_x86_64.c (revision b757af438b42b93f8c6571f026d8b8ef3eaf5fc9)
1 /*	$NetBSD: kvm_x86_64.c,v 1.9 2012/01/10 16:01:16 chs 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 1.9 2012/01/10 16:01:16 chs 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/user.h>
51 #include <sys/proc.h>
52 #include <sys/stat.h>
53 #include <sys/kcore.h>
54 #include <sys/types.h>
55 
56 #include <stdlib.h>
57 #include <unistd.h>
58 #include <nlist.h>
59 #include <kvm.h>
60 
61 #include <uvm/uvm_extern.h>
62 
63 #include <limits.h>
64 #include <db.h>
65 
66 #include "kvm_private.h"
67 
68 #include <machine/kcore.h>
69 #include <machine/pmap.h>
70 #include <machine/pte.h>
71 #include <machine/vmparam.h>
72 
73 void
74 _kvm_freevtop(kvm_t *kd)
75 {
76 
77 	/* Not actually used for anything right now, but safe. */
78 	if (kd->vmst != 0)
79 		free(kd->vmst);
80 }
81 
82 /*ARGSUSED*/
83 int
84 _kvm_initvtop(kvm_t *kd)
85 {
86 
87 	return (0);
88 }
89 
90 /*
91  * Translate a kernel virtual address to a physical address.
92  */
93 int
94 _kvm_kvatop(kvm_t *kd, vaddr_t va, paddr_t *pa)
95 {
96 	cpu_kcore_hdr_t *cpu_kh;
97 	u_long page_off;
98 	pd_entry_t pde;
99 	pt_entry_t pte;
100 	paddr_t pde_pa, pte_pa;
101 
102 	if (ISALIVE(kd)) {
103 		_kvm_err(kd, 0, "vatop called in live kernel!");
104 		return (0);
105 	}
106 
107 	cpu_kh = kd->cpu_data;
108 
109 	/*
110 	 * Find and read all entries to get to the pa.
111 	 */
112 
113 	/*
114 	 * Level 4.
115 	 */
116 	pde_pa = cpu_kh->ptdpaddr + (pl4_pi(va) * sizeof(pd_entry_t));
117 	if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
118 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
119 		_kvm_syserr(kd, 0, "could not read PT level 4 entry");
120 		goto lose;
121 	}
122 	if ((pde & PG_V) == 0) {
123 		_kvm_err(kd, 0, "invalid translation (invalid level 4 PDE)");
124 		goto lose;
125 	}
126 
127 	/*
128 	 * Level 3.
129 	 */
130 	pde_pa = (pde & PG_FRAME) + (pl3_pi(va) * sizeof(pd_entry_t));
131 	if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
132 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
133 		_kvm_syserr(kd, 0, "could not read PT level 3 entry");
134 		goto lose;
135 	}
136 	if ((pde & PG_V) == 0) {
137 		_kvm_err(kd, 0, "invalid translation (invalid level 3 PDE)");
138 		goto lose;
139 	}
140 	if (pde & PG_PS) {
141 		page_off = va & (NBPD_L3 - 1);
142 		*pa = (pde & PG_1GFRAME) + page_off;
143 		return (int)(NBPD_L3 - page_off);
144 	}
145 
146 	/*
147 	 * Level 2.
148 	 */
149 	pde_pa = (pde & PG_FRAME) + (pl2_pi(va) * sizeof(pd_entry_t));
150 	if (_kvm_pread(kd, kd->pmfd, (void *)&pde, sizeof(pde),
151 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
152 		_kvm_syserr(kd, 0, "could not read PT level 2 entry");
153 		goto lose;
154 	}
155 	if ((pde & PG_V) == 0) {
156 		_kvm_err(kd, 0, "invalid translation (invalid level 2 PDE)");
157 		goto lose;
158 	}
159 	if (pde & PG_PS) {
160 		page_off = va & (NBPD_L2 - 1);
161 		*pa = (pde & PG_2MFRAME) + page_off;
162 		return (int)(NBPD_L2 - page_off);
163 	}
164 
165 	/*
166 	 * Level 1.
167 	 */
168 	pte_pa = (pde & PG_FRAME) + (pl1_pi(va) * sizeof(pt_entry_t));
169 	if (_kvm_pread(kd, kd->pmfd, (void *) &pte, sizeof(pte),
170 	    _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
171 		_kvm_syserr(kd, 0, "could not read PTE");
172 		goto lose;
173 	}
174 	/*
175 	 * Validate the PTE and return the physical address.
176 	 */
177 	if ((pte & PG_V) == 0) {
178 		_kvm_err(kd, 0, "invalid translation (invalid PTE)");
179 		goto lose;
180 	}
181 	page_off = va & PGOFSET;
182 	*pa = (pte & PG_FRAME) + page_off;
183 	return (int)(NBPG - page_off);
184 
185  lose:
186 	*pa = (u_long)~0L;
187 	return (0);
188 }
189 
190 /*
191  * Translate a physical address to a file-offset in the crash dump.
192  */
193 off_t
194 _kvm_pa2off(kvm_t *kd, paddr_t pa)
195 {
196 	cpu_kcore_hdr_t *cpu_kh;
197 	phys_ram_seg_t *ramsegs;
198 	off_t off;
199 	int i;
200 
201 	cpu_kh = kd->cpu_data;
202 	ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh));
203 
204 	off = 0;
205 	for (i = 0; i < cpu_kh->nmemsegs; i++) {
206 		if (pa >= ramsegs[i].start &&
207 		    (pa - ramsegs[i].start) < ramsegs[i].size) {
208 			off += (pa - ramsegs[i].start);
209 			break;
210 		}
211 		off += ramsegs[i].size;
212 	}
213 
214 	return (kd->dump_off + off);
215 }
216 
217 /*
218  * Machine-dependent initialization for ALL open kvm descriptors,
219  * not just those for a kernel crash dump.  Some architectures
220  * have to deal with these NOT being constants!  (i.e. m68k)
221  */
222 int
223 _kvm_mdopen(kvm_t *kd)
224 {
225 
226 	kd->usrstack = USRSTACK;
227 	kd->min_uva = VM_MIN_ADDRESS;
228 	kd->max_uva = VM_MAXUSER_ADDRESS;
229 
230 	return (0);
231 }
232