xref: /netbsd-src/lib/libkvm/kvm_mips.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: kvm_mips.c,v 1.5 1997/06/25 21:08:45 jonathan 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. Modified for MIPS by Ralph Campbell.
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_mips.c	8.1 (Berkeley) 6/4/93";
43 #else
44 static char *rcsid = "$NetBSD: kvm_mips.c,v 1.5 1997/06/25 21:08:45 jonathan Exp $";
45 #endif
46 #endif /* LIBC_SCCS and not lint */
47 
48 /*
49  * MIPS 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 <unistd.h>
58 #include <nlist.h>
59 #include <kvm.h>
60 
61 #include <vm/vm.h>
62 #include <vm/vm_param.h>
63 
64 #include <limits.h>
65 #include <db.h>
66 
67 #include "kvm_private.h"
68 
69 #include <mips/cpuregs.h>
70 #include <mips/mips1_pte.h>
71 #include <mips/mips3_pte.h>
72 #include <mips/pmap.h>
73 
74 struct vmstate {
75 	/*pt_entry_t*/u_int	*Sysmap;
76 	u_int		Sysmapsize;
77 	u_int		cpu_arch;
78 };
79 
80 #define KREAD(kd, addr, p)\
81 	(kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p)))
82 
83 void
84 _kvm_freevtop(kd)
85 	kvm_t *kd;
86 {
87 	if (kd->vmst != 0)
88 		free(kd->vmst);
89 }
90 
91 int
92 _kvm_initvtop(kd)
93 	kvm_t *kd;
94 {
95 	struct vmstate *vm;
96 	struct nlist nlist[4];
97 
98 	vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm));
99 	if (vm == 0)
100 		return (-1);
101 	kd->vmst = vm;
102 
103 	nlist[0].n_name = "cpu_arch";
104 	nlist[1].n_name = "Sysmap";
105 	nlist[2].n_name = "Sysmapsize";
106 	nlist[3].n_name = 0;
107 
108 	if (kvm_nlist(kd, nlist) != 0) {
109 		_kvm_err(kd, kd->program, "bad namelist");
110 		return (-1);
111 	}
112 	if (KREAD(kd, (u_long)nlist[0].n_value, &vm->cpu_arch)) {
113 		_kvm_err(kd, kd->program, "cannot read cpu_arch");
114 		return (-1);
115 	}
116 	if (KREAD(kd, (u_long)nlist[1].n_value, &vm->Sysmap)) {
117 		_kvm_err(kd, kd->program, "cannot read Sysmap");
118 		return (-1);
119 	}
120 	if (KREAD(kd, (u_long)nlist[2].n_value, &vm->Sysmapsize)) {
121 		_kvm_err(kd, kd->program, "cannot read mmutype");
122 		return (-1);
123 	}
124 	return (0);
125 }
126 
127 /*
128  * Translate a kernel virtual address to a physical address.
129  */
130 int
131 _kvm_kvatop(kd, va, pa)
132 	kvm_t *kd;
133 	u_long va;
134 	u_long *pa;
135 {
136 	register struct vmstate *vm;
137 	u_long pte, addr, offset;
138 
139 	u_int pgshift, pg_v, pg_frame;
140 
141 	if (ISALIVE(kd)) {
142 		_kvm_err(kd, 0, "vatop called in live kernel!");
143 		return((off_t)0);
144 	}
145 
146 	/* Compute TLB offsets for the level of mips cpu we're running on */
147 	switch (vm->cpu_arch) {
148 	case 1:
149 		pgshift = MIPS1_PG_SHIFT;
150 		pg_v = MIPS1_PG_V;
151 		pg_frame = MIPS1_PG_FRAME;
152 		break;
153 
154 	case 3:
155 		pgshift = MIPS3_PG_SHIFT;
156 		pg_v = MIPS3_PG_V;
157 		pg_frame = MIPS3_PG_FRAME;
158 		break;
159 
160 	default:
161 		_kvm_err(kd, 0, "unknown or unsupported mips CPU family!");
162 		return((off_t)0);
163 	}
164 
165 	vm = kd->vmst;
166 	offset = va & PGOFSET;
167 	/*
168 	 * If we are initializing (kernel segment table pointer not yet set)
169 	 * then return pa == va to avoid infinite recursion.
170 	 */
171 	if (vm->Sysmap == 0) {
172 		*pa = va;
173 		return (NBPG - offset);
174 	}
175 	if (va < KERNBASE ||
176 	    va >= VM_MIN_KERNEL_ADDRESS + vm->Sysmapsize * NBPG)
177 		goto invalid;
178 	if (va < VM_MIN_KERNEL_ADDRESS) {
179 		*pa = MIPS_KSEG0_TO_PHYS(va);
180 		return (NBPG - offset);
181 	}
182 	addr = (u_long)(vm->Sysmap +
183 	    ((va - VM_MIN_KERNEL_ADDRESS) >> pgshift));
184 
185 	/*
186 	 * Can't use KREAD to read kernel segment table entries.
187 	 * Fortunately it is 1-to-1 mapped so we don't have to.
188 	 */
189 	if (lseek(kd->pmfd, (off_t)addr, 0) < 0 ||
190 	    read(kd->pmfd, (char *)&pte, sizeof(pte)) < 0)
191 		goto invalid;
192 	if (!(pte & pg_v))
193 		goto invalid;
194 	*pa = (pte & pg_frame) | offset;
195 	return (NBPG - offset);
196 
197 invalid:
198 	_kvm_err(kd, 0, "invalid address (%x)", va);
199 	return (0);
200 }
201