xref: /netbsd-src/lib/libkvm/kvm_i386.c (revision 001c68bd94f75ce9270b69227c4199fbf34ee396)
1 /*	$NetBSD: kvm_i386.c,v 1.19 2003/01/18 10:40:41 thorpej 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. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  */
39 
40 #include <sys/cdefs.h>
41 #if defined(LIBC_SCCS) && !defined(lint)
42 #if 0
43 static char sccsid[] = "@(#)kvm_hp300.c	8.1 (Berkeley) 6/4/93";
44 #else
45 __RCSID("$NetBSD: kvm_i386.c,v 1.19 2003/01/18 10:40:41 thorpej Exp $");
46 #endif
47 #endif /* LIBC_SCCS and not lint */
48 
49 /*
50  * i386 machine dependent routines for kvm.
51  */
52 
53 #include <sys/param.h>
54 #include <sys/user.h>
55 #include <sys/stat.h>
56 #include <sys/kcore.h>
57 #include <machine/kcore.h>
58 #include <stdlib.h>
59 #include <unistd.h>
60 #include <nlist.h>
61 #include <kvm.h>
62 
63 #include <uvm/uvm_extern.h>
64 
65 #include <limits.h>
66 #include <db.h>
67 
68 #include "kvm_private.h"
69 
70 #include <machine/pmap.h>
71 #include <machine/pte.h>
72 #include <machine/vmparam.h>
73 
74 #ifndef btop
75 #define	btop(x)		(((unsigned)(x)) >> PGSHIFT)	/* XXX */
76 #define	ptob(x)		((caddr_t)((x) << PGSHIFT))	/* XXX */
77 #endif
78 
79 void
80 _kvm_freevtop(kd)
81 	kvm_t *kd;
82 {
83 
84 	/* Not actually used for anything right now, but safe. */
85 	if (kd->vmst != 0)
86 		free(kd->vmst);
87 }
88 
89 /*ARGSUSED*/
90 int
91 _kvm_initvtop(kd)
92 	kvm_t *kd;
93 {
94 
95 	return (0);
96 }
97 
98 /*
99  * Translate a kernel virtual address to a physical address.
100  */
101 int
102 _kvm_kvatop(kd, va, pa)
103 	kvm_t *kd;
104 	u_long va;
105 	u_long *pa;
106 {
107 	cpu_kcore_hdr_t *cpu_kh;
108 	u_long page_off;
109 	pd_entry_t pde;
110 	pt_entry_t pte;
111 	u_long pde_pa, pte_pa;
112 
113 	if (ISALIVE(kd)) {
114 		_kvm_err(kd, 0, "vatop called in live kernel!");
115 		return (0);
116 	}
117 
118 	cpu_kh = kd->cpu_data;
119 	page_off = va & PGOFSET;
120 
121 	/*
122 	 * Find and read the page directory entry.
123 	 */
124 	pde_pa = cpu_kh->ptdpaddr + (pdei(va) * sizeof(pd_entry_t));
125 	if (pread(kd->pmfd, (void *)&pde, sizeof(pde),
126 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
127 		_kvm_syserr(kd, 0, "could not read PDE");
128 		goto lose;
129 	}
130 
131 	/*
132 	 * Find and read the page table entry.
133 	 */
134 	if ((pde & PG_V) == 0) {
135 		_kvm_err(kd, 0, "invalid translation (invalid PDE)");
136 		goto lose;
137 	}
138 	pte_pa = (pde & PG_FRAME) + (ptei(va) * sizeof(pt_entry_t));
139 	if (pread(kd->pmfd, (void *) &pte, sizeof(pte),
140 	    _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
141 		_kvm_syserr(kd, 0, "could not read PTE");
142 		goto lose;
143 	}
144 
145 	/*
146 	 * Validate the PTE and return the physical address.
147 	 */
148 	if ((pte & PG_V) == 0) {
149 		_kvm_err(kd, 0, "invalid translation (invalid PTE)");
150 		goto lose;
151 	}
152 	*pa = (pte & PG_FRAME) + page_off;
153 	return (int)(NBPG - page_off);
154 
155  lose:
156 	*pa = (u_long)~0L;
157 	return (0);
158 }
159 
160 /*
161  * Translate a physical address to a file-offset in the crash dump.
162  */
163 off_t
164 _kvm_pa2off(kd, pa)
165 	kvm_t *kd;
166 	u_long pa;
167 {
168 	cpu_kcore_hdr_t *cpu_kh;
169 	phys_ram_seg_t *ramsegs;
170 	off_t off;
171 	int i;
172 
173 	cpu_kh = kd->cpu_data;
174 	ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh));
175 
176 	off = 0;
177 	for (i = 0; i < cpu_kh->nmemsegs; i++) {
178 		if (pa >= ramsegs[i].start &&
179 		    (pa - ramsegs[i].start) < ramsegs[i].size) {
180 			off += (pa - ramsegs[i].start);
181 			break;
182 		}
183 		off += ramsegs[i].size;
184 	}
185 
186 	return (kd->dump_off + off);
187 }
188 
189 /*
190  * Machine-dependent initialization for ALL open kvm descriptors,
191  * not just those for a kernel crash dump.  Some architectures
192  * have to deal with these NOT being constants!  (i.e. m68k)
193  */
194 int
195 _kvm_mdopen(kd)
196 	kvm_t	*kd;
197 {
198 
199 	kd->usrstack = USRSTACK;
200 	kd->min_uva = VM_MIN_ADDRESS;
201 	kd->max_uva = VM_MAXUSER_ADDRESS;
202 
203 	return (0);
204 }
205