xref: /netbsd-src/lib/libkvm/kvm_mips.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*-
2  * Copyright (c) 1989, 1992, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software developed by the Computer Systems
6  * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
7  * BG 91-66 and contributed to Berkeley. Modified for MIPS by Ralph Campbell.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #if defined(LIBC_SCCS) && !defined(lint)
39 static char sccsid[] = "@(#)kvm_mips.c	8.1 (Berkeley) 6/4/93";
40 #endif /* LIBC_SCCS and not lint */
41 /*
42  * MIPS machine dependent routines for kvm.  Hopefully, the forthcoming
43  * vm code will one day obsolete this module.
44  */
45 
46 #include <sys/param.h>
47 #include <sys/user.h>
48 #include <sys/proc.h>
49 #include <sys/stat.h>
50 #include <unistd.h>
51 #include <nlist.h>
52 #include <kvm.h>
53 
54 #include <vm/vm.h>
55 #include <vm/vm_param.h>
56 
57 #include <limits.h>
58 #include <db.h>
59 
60 #include "kvm_private.h"
61 
62 #include <machine/machConst.h>
63 #include <machine/pte.h>
64 #include <machine/pmap.h>
65 
66 struct vmstate {
67 	pt_entry_t	*Sysmap;
68 	u_int		Sysmapsize;
69 };
70 
71 #define KREAD(kd, addr, p)\
72 	(kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p)))
73 
74 void
75 _kvm_freevtop(kd)
76 	kvm_t *kd;
77 {
78 	if (kd->vmst != 0)
79 		free(kd->vmst);
80 }
81 
82 int
83 _kvm_initvtop(kd)
84 	kvm_t *kd;
85 {
86 	struct vmstate *vm;
87 	struct nlist nlist[3];
88 
89 	vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm));
90 	if (vm == 0)
91 		return (-1);
92 	kd->vmst = vm;
93 
94 	nlist[0].n_name = "Sysmap";
95 	nlist[1].n_name = "Sysmapsize";
96 	nlist[2].n_name = 0;
97 
98 	if (kvm_nlist(kd, nlist) != 0) {
99 		_kvm_err(kd, kd->program, "bad namelist");
100 		return (-1);
101 	}
102 	if (KREAD(kd, (u_long)nlist[0].n_value, &vm->Sysmap)) {
103 		_kvm_err(kd, kd->program, "cannot read Sysmap");
104 		return (-1);
105 	}
106 	if (KREAD(kd, (u_long)nlist[1].n_value, &vm->Sysmapsize)) {
107 		_kvm_err(kd, kd->program, "cannot read mmutype");
108 		return (-1);
109 	}
110 	return (0);
111 }
112 
113 /*
114  * Translate a kernel virtual address to a physical address.
115  */
116 int
117 _kvm_kvatop(kd, va, pa)
118 	kvm_t *kd;
119 	u_long va;
120 	u_long *pa;
121 {
122 	register struct vmstate *vm;
123 	u_long pte, addr, offset;
124 
125 	if (ISALIVE(kd)) {
126 		_kvm_err(kd, 0, "vatop called in live kernel!");
127 		return((off_t)0);
128 	}
129 	vm = kd->vmst;
130 	offset = va & PGOFSET;
131 	/*
132 	 * If we are initializing (kernel segment table pointer not yet set)
133 	 * then return pa == va to avoid infinite recursion.
134 	 */
135 	if (vm->Sysmap == 0) {
136 		*pa = va;
137 		return (NBPG - offset);
138 	}
139 	if (va < KERNBASE ||
140 	    va >= VM_MIN_KERNEL_ADDRESS + vm->Sysmapsize * NBPG)
141 		goto invalid;
142 	if (va < VM_MIN_KERNEL_ADDRESS) {
143 		*pa = MACH_CACHED_TO_PHYS(va);
144 		return (NBPG - offset);
145 	}
146 	addr = (u_long)(vm->Sysmap + ((va - VM_MIN_KERNEL_ADDRESS) >> PGSHIFT));
147 	/*
148 	 * Can't use KREAD to read kernel segment table entries.
149 	 * Fortunately it is 1-to-1 mapped so we don't have to.
150 	 */
151 	if (lseek(kd->pmfd, (off_t)addr, 0) < 0 ||
152 	    read(kd->pmfd, (char *)&pte, sizeof(pte)) < 0)
153 		goto invalid;
154 	if (!(pte & PG_V))
155 		goto invalid;
156 	*pa = (pte & PG_FRAME) | offset;
157 	return (NBPG - offset);
158 
159 invalid:
160 	_kvm_err(kd, 0, "invalid address (%x)", va);
161 	return (0);
162 }
163 
164 /*
165  * Translate a user virtual address to a physical address.
166  */
167 int
168 _kvm_uvatop(kd, p, va, pa)
169 	kvm_t *kd;
170 	const struct proc *p;
171 	u_long va;
172 	u_long *pa;
173 {
174 	register struct vmspace *vms = p->p_vmspace;
175 	u_long kva, offset;
176 
177 	if (va >= KERNBASE)
178 		goto invalid;
179 
180 	/* read the address of the first level table */
181 	kva = (u_long)&vms->vm_pmap.pm_segtab;
182 	if (kvm_read(kd, kva, (char *)&kva, sizeof(kva)) != sizeof(kva))
183 		goto invalid;
184 	if (kva == 0)
185 		goto invalid;
186 
187 	/* read the address of the second level table */
188 	kva += (va >> SEGSHIFT) * sizeof(caddr_t);
189 	if (kvm_read(kd, kva, (char *)&kva, sizeof(kva)) != sizeof(kva))
190 		goto invalid;
191 	if (kva == 0)
192 		goto invalid;
193 
194 	/* read the pte from the second level table */
195 	kva += (va >> PGSHIFT) & (NPTEPG - 1);
196 	if (kvm_read(kd, kva, (char *)&kva, sizeof(kva)) != sizeof(kva))
197 		goto invalid;
198 	if (!(kva & PG_V))
199 		goto invalid;
200 	offset = va & PGOFSET;
201 	*pa = (kva & PG_FRAME) | offset;
202 	return (NBPG - offset);
203 
204 invalid:
205 	_kvm_err(kd, 0, "invalid address (%x)", va);
206 	return (0);
207 }
208