xref: /netbsd-src/lib/libkvm/kvm_i386.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: kvm_i386.c,v 1.9 1996/03/18 22:33:38 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 #if defined(LIBC_SCCS) && !defined(lint)
41 #if 0
42 static char sccsid[] = "@(#)kvm_hp300.c	8.1 (Berkeley) 6/4/93";
43 #else
44 static char *rcsid = "$NetBSD: kvm_i386.c,v 1.9 1996/03/18 22:33:38 thorpej Exp $";
45 #endif
46 #endif /* LIBC_SCCS and not lint */
47 
48 /*
49  * i386 machine dependent routines for kvm.  Hopefully, the forthcoming
50  * vm code will one day obsolete this module.
51  */
52 
53 #include <sys/param.h>
54 #include <sys/user.h>
55 #include <sys/proc.h>
56 #include <sys/stat.h>
57 #include <stdlib.h>
58 #include <unistd.h>
59 #include <nlist.h>
60 #include <kvm.h>
61 
62 #include <vm/vm.h>
63 #include <vm/vm_param.h>
64 
65 #include <limits.h>
66 #include <db.h>
67 
68 #include "kvm_private.h"
69 
70 #include <machine/pte.h>
71 
72 #ifndef btop
73 #define	btop(x)		(((unsigned)(x)) >> PGSHIFT)	/* XXX */
74 #define	ptob(x)		((caddr_t)((x) << PGSHIFT))	/* XXX */
75 #endif
76 
77 struct vmstate {
78 	pd_entry_t *PTD;
79 };
80 
81 void
82 _kvm_freevtop(kd)
83 	kvm_t *kd;
84 {
85 	if (kd->vmst != 0) {
86 		if (kd->vmst->PTD != 0)
87 			free(kd->vmst->PTD);
88 
89 		free(kd->vmst);
90 	}
91 }
92 
93 int
94 _kvm_initvtop(kd)
95 	kvm_t *kd;
96 {
97 	struct vmstate *vm;
98 	struct nlist nlist[2];
99 	u_long pa;
100 
101 	vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm));
102 	if (vm == 0)
103 		return (-1);
104 	kd->vmst = vm;
105 
106 	nlist[0].n_name = "_PTDpaddr";
107 	nlist[1].n_name = 0;
108 
109 	if (kvm_nlist(kd, nlist) != 0) {
110 		_kvm_err(kd, kd->program, "bad namelist");
111 		return (-1);
112 	}
113 
114 	vm->PTD = 0;
115 
116 	if (lseek(kd->pmfd, (off_t)(nlist[0].n_value - KERNBASE), 0) == -1 &&
117 	    errno != 0) {
118 		_kvm_syserr(kd, kd->program, "kvm_lseek");
119 		goto invalid;
120 	}
121 	if (read(kd->pmfd, &pa, sizeof pa) != sizeof pa) {
122 		_kvm_syserr(kd, kd->program, "kvm_read");
123 		goto invalid;
124 	}
125 
126 	vm->PTD = (pd_entry_t *)_kvm_malloc(kd, NBPG);
127 
128 	if (lseek(kd->pmfd, (off_t)pa, 0) == -1 && errno != 0) {
129 		_kvm_syserr(kd, kd->program, "kvm_lseek");
130 		goto invalid;
131 	}
132 	if (read(kd->pmfd, vm->PTD, NBPG) != NBPG) {
133 		_kvm_syserr(kd, kd->program, "kvm_read");
134 		goto invalid;
135 	}
136 
137 	return (0);
138 
139 invalid:
140 	if (vm->PTD != 0)
141 		free(vm->PTD);
142 	return (-1);
143 }
144 
145 /*
146  * Translate a kernel virtual address to a physical address.
147  */
148 int
149 _kvm_kvatop(kd, va, pa)
150 	kvm_t *kd;
151 	u_long va;
152 	u_long *pa;
153 {
154 	struct vmstate *vm;
155 	u_long offset;
156 	u_long pte_pa;
157 	pt_entry_t pte;
158 
159 	if (ISALIVE(kd)) {
160 		_kvm_err(kd, 0, "vatop called in live kernel!");
161 		return(0);
162 	}
163 
164 	vm = kd->vmst;
165 	offset = va & PGOFSET;
166 
167         /*
168          * If we are initializing (kernel page table descriptor pointer
169 	 * not yet set) * then return pa == va to avoid infinite recursion.
170          */
171         if (vm->PTD == 0) {
172                 *pa = va;
173                 return (NBPG - offset);
174         }
175 	if ((vm->PTD[pdei(va)] & PG_V) == 0)
176 		goto invalid;
177 
178 	pte_pa = (vm->PTD[pdei(va)] & PG_FRAME) +
179 	    (ptei(va) * sizeof(pt_entry_t));
180 	/* XXX READ PHYSICAL XXX */
181 	{
182 		if (lseek(kd->pmfd, (off_t)pte_pa, 0) == -1 && errno != 0) {
183 			_kvm_syserr(kd, kd->program, "kvm_lseek");
184 			goto invalid;
185 		}
186 		if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) {
187 			_kvm_syserr(kd, kd->program, "kvm_read");
188 			goto invalid;
189 		}
190 	}
191 
192 	*pa = (pte & PG_FRAME) + offset;
193 	return (NBPG - offset);
194 
195 invalid:
196 	_kvm_err(kd, 0, "invalid address (%x)", va);
197 	return (0);
198 }
199