xref: /netbsd-src/lib/libkvm/kvm_i386.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: kvm_i386.c,v 1.17 2000/06/29 06:34:24 mrg 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 1.17 2000/06/29 06:34:24 mrg 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/proc.h>
56 #include <sys/stat.h>
57 #include <sys/kcore.h>
58 #include <machine/kcore.h>
59 #include <stdlib.h>
60 #include <unistd.h>
61 #include <nlist.h>
62 #include <kvm.h>
63 
64 #include <uvm/uvm_extern.h>
65 
66 #include <limits.h>
67 #include <db.h>
68 
69 #include "kvm_private.h"
70 
71 #include <machine/pte.h>
72 
73 #ifndef btop
74 #define	btop(x)		(((unsigned)(x)) >> PGSHIFT)	/* XXX */
75 #define	ptob(x)		((caddr_t)((x) << PGSHIFT))	/* XXX */
76 #endif
77 
78 void
79 _kvm_freevtop(kd)
80 	kvm_t *kd;
81 {
82 
83 	/* Not actually used for anything right now, but safe. */
84 	if (kd->vmst != 0)
85 		free(kd->vmst);
86 }
87 
88 /*ARGSUSED*/
89 int
90 _kvm_initvtop(kd)
91 	kvm_t *kd;
92 {
93 
94 	return (0);
95 }
96 
97 /*
98  * Translate a kernel virtual address to a physical address.
99  */
100 int
101 _kvm_kvatop(kd, va, pa)
102 	kvm_t *kd;
103 	u_long va;
104 	u_long *pa;
105 {
106 	cpu_kcore_hdr_t *cpu_kh;
107 	u_long page_off;
108 	pd_entry_t pde;
109 	pt_entry_t pte;
110 	u_long pde_pa, pte_pa;
111 
112 	if (ISALIVE(kd)) {
113 		_kvm_err(kd, 0, "vatop called in live kernel!");
114 		return (0);
115 	}
116 
117 	cpu_kh = kd->cpu_data;
118 	page_off = va & PGOFSET;
119 
120 	/*
121 	 * Find and read the page directory entry.
122 	 */
123 	pde_pa = cpu_kh->ptdpaddr + (pdei(va) * sizeof(pd_entry_t));
124 	if (pread(kd->pmfd, (void *)&pde, sizeof(pde),
125 	    _kvm_pa2off(kd, pde_pa)) != sizeof(pde)) {
126 		_kvm_syserr(kd, 0, "could not read PDE");
127 		goto lose;
128 	}
129 
130 	/*
131 	 * Find and read the page table entry.
132 	 */
133 	if ((pde & PG_V) == 0) {
134 		_kvm_err(kd, 0, "invalid translation (invalid PDE)");
135 		goto lose;
136 	}
137 	pte_pa = (pde & PG_FRAME) + (ptei(va) * sizeof(pt_entry_t));
138 	if (pread(kd->pmfd, (void *) &pte, sizeof(pte),
139 	    _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
140 		_kvm_syserr(kd, 0, "could not read PTE");
141 		goto lose;
142 	}
143 
144 	/*
145 	 * Validate the PTE and return the physical address.
146 	 */
147 	if ((pte & PG_V) == 0) {
148 		_kvm_err(kd, 0, "invalid translation (invalid PTE)");
149 		goto lose;
150 	}
151 	*pa = (pte & PG_FRAME) + page_off;
152 	return (int)(NBPG - page_off);
153 
154  lose:
155 	*pa = (u_long)~0L;
156 	return (0);
157 }
158 
159 /*
160  * Translate a physical address to a file-offset in the crash dump.
161  */
162 off_t
163 _kvm_pa2off(kd, pa)
164 	kvm_t *kd;
165 	u_long pa;
166 {
167 	cpu_kcore_hdr_t *cpu_kh;
168 	phys_ram_seg_t *ramsegs;
169 	off_t off;
170 	int i;
171 
172 	cpu_kh = kd->cpu_data;
173 	ramsegs = (void *)((char *)(void *)cpu_kh + ALIGN(sizeof *cpu_kh));
174 
175 	off = 0;
176 	for (i = 0; i < cpu_kh->nmemsegs; i++) {
177 		if (pa >= ramsegs[i].start &&
178 		    (pa - ramsegs[i].start) < ramsegs[i].size) {
179 			off += (pa - ramsegs[i].start);
180 			break;
181 		}
182 		off += ramsegs[i].size;
183 	}
184 
185 	return (kd->dump_off + off);
186 }
187 
188 /*
189  * Machine-dependent initialization for ALL open kvm descriptors,
190  * not just those for a kernel crash dump.  Some architectures
191  * have to deal with these NOT being constants!  (i.e. m68k)
192  */
193 int
194 _kvm_mdopen(kd)
195 	kvm_t	*kd;
196 {
197 
198 	kd->usrstack = USRSTACK;
199 	kd->min_uva = VM_MIN_ADDRESS;
200 	kd->max_uva = VM_MAXUSER_ADDRESS;
201 
202 	return (0);
203 }
204