xref: /minix/lib/libkvm/kvm_mips.c (revision b89261ba)
1 /* $NetBSD: kvm_mips.c,v 1.22 2014/02/19 20:21:22 dsl Exp $ */
2 
3 /*
4  * Copyright (c) 1994, 1995 Carnegie-Mellon University.
5  * All rights reserved.
6  *
7  * Author: Chris G. Demetriou
8  *
9  * Permission to use, copy, modify and distribute this software and
10  * its documentation is hereby granted, provided that both the copyright
11  * notice and this permission notice appear in all copies of the
12  * software, derivative works or modified versions, and any portions
13  * thereof, and that both notices appear in supporting documentation.
14  *
15  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
17  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18  *
19  * Carnegie Mellon requests users of this software to return to
20  *
21  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
22  *  School of Computer Science
23  *  Carnegie Mellon University
24  *  Pittsburgh PA 15213-3890
25  *
26  * any improvements or extensions that they make and grant Carnegie the
27  * rights to redistribute these changes.
28  */
29 
30 /*
31  * Modified for NetBSD/mips by Jason R. Thorpe, Numerical Aerospace
32  * Simulation Facility, NASA Ames Research Center.
33  */
34 
35 #include <sys/cdefs.h>
36 #if defined(LIBC_SCCS) && !defined(lint)
37 __RCSID("$NetBSD: kvm_mips.c,v 1.22 2014/02/19 20:21:22 dsl Exp $");
38 #endif /* LIBC_SCCS and not lint */
39 
40 /*
41  * MIPS machine dependent routines for kvm.
42  */
43 
44 #include <sys/param.h>
45 #include <sys/proc.h>
46 #include <sys/stat.h>
47 #include <sys/kcore.h>
48 #include <sys/types.h>
49 
50 #include <machine/kcore.h>
51 
52 #include <stdlib.h>
53 #include <unistd.h>
54 #include <nlist.h>
55 #include <kvm.h>
56 
57 #include <uvm/uvm_extern.h>
58 
59 #include <limits.h>
60 #include <db.h>
61 
62 #include "kvm_private.h"
63 
64 #include <mips/cpuregs.h>
65 #include <mips/vmparam.h>
66 
67 void
68 _kvm_freevtop(kvm_t *kd)
69 {
70 
71 	/* Not actually used for anything right now, but safe. */
72 	if (kd->vmst != 0)
73 		free(kd->vmst);
74 }
75 
76 int
77 _kvm_initvtop(kvm_t *kd)
78 {
79 
80 	return (0);
81 }
82 
83 /*
84  * Translate a kernel virtual address to a physical address.
85  */
86 int
87 _kvm_kvatop(kvm_t *kd, vaddr_t va, paddr_t *pa)
88 {
89 	cpu_kcore_hdr_t *cpu_kh;
90 	int page_off;
91 	u_int pte;
92 	paddr_t pte_pa;
93 
94 	if (ISALIVE(kd)) {
95 		_kvm_err(kd, 0, "vatop called in live kernel!");
96 		return((off_t)0);
97 	}
98 
99 	cpu_kh = kd->cpu_data;
100 	page_off = va & PGOFSET;
101 
102 #ifdef _LP64
103 	if (MIPS_XKPHYS_P(va)) {
104 		/*
105 		 * Direct-mapped cached address: just convert it.
106 		 */
107 		*pa = MIPS_XKPHYS_TO_PHYS(va);
108 		return (NBPG - page_off);
109 	}
110 
111 	if (va < MIPS_XKPHYS_START) {
112 		/*
113 		 * XUSEG (user virtual address space) - invalid.
114 		 */
115 		_kvm_err(kd, 0, "invalid kernel virtual address");
116 		goto lose;
117 	}
118 #else
119 	if (va < MIPS_KSEG0_START) {
120 		/*
121 		 * KUSEG (user virtual address space) - invalid.
122 		 */
123 		_kvm_err(kd, 0, "invalid kernel virtual address");
124 		goto lose;
125 	}
126 #endif
127 
128 	if (MIPS_KSEG0_P(va)) {
129 		/*
130 		 * Direct-mapped cached address: just convert it.
131 		 */
132 		*pa = MIPS_KSEG0_TO_PHYS(va);
133 		return (NBPG - page_off);
134 	}
135 
136 	if (MIPS_KSEG1_P(va)) {
137 		/*
138 		 * Direct-mapped uncached address: just convert it.
139 		 */
140 		*pa = MIPS_KSEG1_TO_PHYS(va);
141 		return (NBPG - page_off);
142 	}
143 
144 #ifdef _LP64
145 	if (va >= MIPS_KSEG2_START) {
146 		/*
147 		 * KUSEG (user virtual address space) - invalid.
148 		 */
149 		_kvm_err(kd, 0, "invalid kernel virtual address");
150 		goto lose;
151 	}
152 #endif
153 
154 	/*
155 	 * We now know that we're a KSEG2 (kernel virtually mapped)
156 	 * address.  Translate the address using the pmap's kernel
157 	 * page table.
158 	 */
159 
160 	/*
161 	 * Step 1: Make sure the kernel page table has a translation
162 	 * for the address.
163 	 */
164 #ifdef _LP64
165 	if (va >= (MIPS_XKSEG_START + (cpu_kh->sysmapsize * NBPG))) {
166 		_kvm_err(kd, 0, "invalid XKSEG address");
167 		goto lose;
168 	}
169 #else
170 	if (va >= (MIPS_KSEG2_START + (cpu_kh->sysmapsize * NBPG))) {
171 		_kvm_err(kd, 0, "invalid KSEG2 address");
172 		goto lose;
173 	}
174 #endif
175 
176 	/*
177 	 * Step 2: Locate and read the PTE.
178 	 */
179 	pte_pa = cpu_kh->sysmappa +
180 	    (((va - MIPS_KSEG2_START) >> PGSHIFT) * sizeof(u_int));
181 	if (_kvm_pread(kd, kd->pmfd, &pte, sizeof(pte),
182 	    _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
183 		_kvm_syserr(kd, 0, "could not read PTE");
184 		goto lose;
185 	}
186 
187 	/*
188 	 * Step 3: Validate the PTE and return the physical address.
189 	 */
190 	if ((pte & cpu_kh->pg_v) == 0) {
191 		_kvm_err(kd, 0, "invalid translation (invalid PTE)");
192 		goto lose;
193 	}
194 	*pa = (((pte & cpu_kh->pg_frame) >> cpu_kh->pg_shift) << PGSHIFT) +
195 	    page_off;
196 	return (NBPG - page_off);
197 
198  lose:
199 	*pa = -1;
200 	return (0);
201 }
202 
203 /*
204  * Translate a physical address to a file-offset in the crash dump.
205  */
206 off_t
207 _kvm_pa2off(kvm_t *kd, paddr_t pa)
208 {
209 	cpu_kcore_hdr_t *cpu_kh;
210 	phys_ram_seg_t *ramsegs;
211 	off_t off;
212 	int i;
213 
214 	cpu_kh = kd->cpu_data;
215 	ramsegs = (phys_ram_seg_t *)((char *)cpu_kh + ALIGN(sizeof *cpu_kh));
216 
217 	off = 0;
218 	for (i = 0; i < cpu_kh->nmemsegs; i++) {
219 		if (pa >= ramsegs[i].start &&
220 		    (pa - ramsegs[i].start) < ramsegs[i].size) {
221 			off += (pa - ramsegs[i].start);
222 			break;
223 		}
224 		off += ramsegs[i].size;
225 	}
226 
227 	return (kd->dump_off + off);
228 }
229 
230 /*
231  * Machine-dependent initialization for ALL open kvm descriptors,
232  * not just those for a kernel crash dump.  Some architectures
233  * have to deal with these NOT being constants!  (i.e. m68k)
234  */
235 int
236 _kvm_mdopen(kvm_t *kd)
237 {
238 
239 	kd->usrstack = USRSTACK;
240 	kd->min_uva = VM_MIN_ADDRESS;
241 	kd->max_uva = VM_MAXUSER_ADDRESS;
242 
243 	return (0);
244 }
245