xref: /netbsd-src/lib/libkvm/kvm_m68k.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.
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 /* from: static char sccsid[] = "@(#)kvm_hp300.c	8.1 (Berkeley) 6/4/93"; */
40 static char *rcsid = "$Id: kvm_m68k.c,v 1.1 1994/05/09 04:09:24 cgd Exp $";
41 #endif /* LIBC_SCCS and not lint */
42 
43 /*
44  * m68k machine dependent routines for kvm.  Hopefully, the forthcoming
45  * vm code will one day obsolete this module.
46  */
47 
48 #include <sys/param.h>
49 #include <sys/user.h>
50 #include <sys/proc.h>
51 #include <sys/stat.h>
52 #include <unistd.h>
53 #include <nlist.h>
54 #include <kvm.h>
55 
56 #include <vm/vm.h>
57 #include <vm/vm_param.h>
58 
59 #include <limits.h>
60 #include <db.h>
61 
62 #include "kvm_private.h"
63 
64 #include <machine/pte.h>
65 
66 #ifndef btop
67 #define	btop(x)		(((unsigned)(x)) >> PGSHIFT)	/* XXX */
68 #define	ptob(x)		((caddr_t)((x) << PGSHIFT))	/* XXX */
69 #endif
70 
71 struct vmstate {
72 	u_long lowram;
73 	int mmutype;
74 	struct ste *Sysseg;
75 };
76 
77 #define KREAD(kd, addr, p)\
78 	(kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p)))
79 
80 void
81 _kvm_freevtop(kd)
82 	kvm_t *kd;
83 {
84 	if (kd->vmst != 0)
85 		free(kd->vmst);
86 }
87 
88 int
89 _kvm_initvtop(kd)
90 	kvm_t *kd;
91 {
92 	struct vmstate *vm;
93 	struct nlist nlist[4];
94 
95 	vm = (struct vmstate *)_kvm_malloc(kd, sizeof(*vm));
96 	if (vm == 0)
97 		return (-1);
98 	kd->vmst = vm;
99 
100 	nlist[0].n_name = "_lowram";
101 	nlist[1].n_name = "_mmutype";
102 	nlist[2].n_name = "_Sysseg";
103 	nlist[3].n_name = 0;
104 
105 	if (kvm_nlist(kd, nlist) != 0) {
106 		_kvm_err(kd, kd->program, "bad namelist");
107 		return (-1);
108 	}
109 	vm->Sysseg = 0;
110 	if (KREAD(kd, (u_long)nlist[0].n_value, &vm->lowram)) {
111 		_kvm_err(kd, kd->program, "cannot read lowram");
112 		return (-1);
113 	}
114 	if (KREAD(kd, (u_long)nlist[1].n_value, &vm->mmutype)) {
115 		_kvm_err(kd, kd->program, "cannot read mmutype");
116 		return (-1);
117 	}
118 	if (KREAD(kd, (u_long)nlist[2].n_value, &vm->Sysseg)) {
119 		_kvm_err(kd, kd->program, "cannot read segment table");
120 		return (-1);
121 	}
122 	return (0);
123 }
124 
125 static int
126 _kvm_vatop(kd, sta, va, pa)
127 	kvm_t *kd;
128 	struct ste *sta;
129 	u_long va;
130 	u_long *pa;
131 {
132 	register struct vmstate *vm;
133 	register u_long lowram;
134 	register u_long addr;
135 	int p, ste, pte;
136 	int offset;
137 
138 	if (ISALIVE(kd)) {
139 		_kvm_err(kd, 0, "vatop called in live kernel!");
140 		return((off_t)0);
141 	}
142 	vm = kd->vmst;
143 	offset = va & PGOFSET;
144 	/*
145 	 * If we are initializing (kernel segment table pointer not yet set)
146 	 * then return pa == va to avoid infinite recursion.
147 	 */
148 	if (vm->Sysseg == 0) {
149 		*pa = va;
150 		return (NBPG - offset);
151 	}
152 	lowram = vm->lowram;
153 	if (vm->mmutype == -2) {
154 		struct ste *sta2;
155 
156 		addr = (u_long)&sta[va >> SG4_SHIFT1];
157 		/*
158 		 * Can't use KREAD to read kernel segment table entries.
159 		 * Fortunately it is 1-to-1 mapped so we don't have to.
160 		 */
161 		if (sta == vm->Sysseg) {
162 			if (lseek(kd->pmfd, (off_t)addr, 0) == -1 ||
163 			    read(kd->pmfd, (char *)&ste, sizeof(ste)) < 0)
164 				goto invalid;
165 		} else if (KREAD(kd, addr, &ste))
166 			goto invalid;
167 		if ((ste & SG_V) == 0) {
168 			_kvm_err(kd, 0, "invalid level 1 descriptor (%x)",
169 				 ste);
170 			return((off_t)0);
171 		}
172 		sta2 = (struct ste *)(ste & SG4_ADDR1);
173 		addr = (u_long)&sta2[(va & SG4_MASK2) >> SG4_SHIFT2];
174 		/*
175 		 * Address from level 1 STE is a physical address,
176 		 * so don't use kvm_read.
177 		 */
178 		if (lseek(kd->pmfd, (off_t)(addr - lowram), 0) == -1 ||
179 		    read(kd->pmfd, (char *)&ste, sizeof(ste)) < 0)
180 			goto invalid;
181 		if ((ste & SG_V) == 0) {
182 			_kvm_err(kd, 0, "invalid level 2 descriptor (%x)",
183 				 ste);
184 			return((off_t)0);
185 		}
186 		sta2 = (struct ste *)(ste & SG4_ADDR2);
187 		addr = (u_long)&sta2[(va & SG4_MASK3) >> SG4_SHIFT3];
188 	} else {
189 		addr = (u_long)&sta[va >> SEGSHIFT];
190 		/*
191 		 * Can't use KREAD to read kernel segment table entries.
192 		 * Fortunately it is 1-to-1 mapped so we don't have to.
193 		 */
194 		if (sta == vm->Sysseg) {
195 			if (lseek(kd->pmfd, (off_t)addr, 0) == -1 ||
196 			    read(kd->pmfd, (char *)&ste, sizeof(ste)) < 0)
197 				goto invalid;
198 		} else if (KREAD(kd, addr, &ste))
199 			goto invalid;
200 		if ((ste & SG_V) == 0) {
201 			_kvm_err(kd, 0, "invalid segment (%x)", ste);
202 			return((off_t)0);
203 		}
204 		p = btop(va & SG_PMASK);
205 		addr = (ste & SG_FRAME) + (p * sizeof(struct pte));
206 	}
207 	/*
208 	 * Address from STE is a physical address so don't use kvm_read.
209 	 */
210 	if (lseek(kd->pmfd, (off_t)(addr - lowram), 0) == -1 ||
211 	    read(kd->pmfd, (char *)&pte, sizeof(pte)) < 0)
212 		goto invalid;
213 	addr = pte & PG_FRAME;
214 	if (pte == PG_NV) {
215 		_kvm_err(kd, 0, "page not valid");
216 		return (0);
217 	}
218 	*pa = addr - lowram + offset;
219 
220 	return (NBPG - offset);
221 invalid:
222 	_kvm_err(kd, 0, "invalid address (%x)", va);
223 	return (0);
224 }
225 
226 int
227 _kvm_kvatop(kd, va, pa)
228 	kvm_t *kd;
229 	u_long va;
230 	u_long *pa;
231 {
232 	return (_kvm_vatop(kd, (u_long)kd->vmst->Sysseg, va, pa));
233 }
234 
235 /*
236  * Translate a user virtual address to a physical address.
237  */
238 int
239 _kvm_uvatop(kd, p, va, pa)
240 	kvm_t *kd;
241 	const struct proc *p;
242 	u_long va;
243 	u_long *pa;
244 {
245 	register struct vmspace *vms = p->p_vmspace;
246 	int kva;
247 
248 	/*
249 	 * If this is a live kernel we just look it up in the kernel
250 	 * virtually allocated flat 4mb page table (i.e. let the kernel
251 	 * do the table walk).  In this way, we avoid needing to know
252 	 * the MMU type.
253 	 */
254 	if (ISALIVE(kd)) {
255 		struct pte *ptab;
256 		int pte, offset;
257 
258 		kva = (int)&vms->vm_pmap.pm_ptab;
259 		if (KREAD(kd, kva, &ptab)) {
260 			_kvm_err(kd, 0, "invalid address (%x)", va);
261 			return (0);
262 		}
263 		kva = (int)&ptab[btop(va)];
264 		if (KREAD(kd, kva, &pte) || (pte & PG_V) == 0) {
265 			_kvm_err(kd, 0, "invalid address (%x)", va);
266 			return (0);
267 		}
268 		offset = va & PGOFSET;
269 		*pa = (pte & PG_FRAME) | offset;
270 		return (NBPG - offset);
271 	}
272 	/*
273 	 * Otherwise, we just walk the table ourself.
274 	 */
275 	kva = (int)&vms->vm_pmap.pm_stab;
276 	if (KREAD(kd, kva, &kva)) {
277 		_kvm_err(kd, 0, "invalid address (%x)", va);
278 		return (0);
279 	}
280 	return (_kvm_vatop(kd, kva, va, pa));
281 }
282