xref: /openbsd/lib/libkvm/kvm_sh.c (revision 404b540a)
1 /*	$OpenBSD: kvm_sh.c,v 1.2 2007/03/03 21:37:27 miod Exp $	*/
2 
3 /*
4  * Copyright (c) 2007 Miodrag Vallat.
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice, this permission notice, and the disclaimer below
9  * appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/param.h>
21 #include <sys/core.h>
22 #include <sys/kcore.h>
23 
24 #include <unistd.h>
25 #include <stdlib.h>
26 #include <nlist.h>
27 #include <kvm.h>
28 
29 #include <db.h>
30 
31 #include "kvm_private.h"
32 
33 #include <machine/cpu.h>
34 #include <machine/kcore.h>
35 #include <machine/pte.h>
36 #include <machine/vmparam.h>
37 
38 void
39 _kvm_freevtop(kvm_t *kd)
40 {
41 }
42 
43 int
44 _kvm_initvtop(kvm_t *kd)
45 {
46 	return (0);
47 }
48 
49 /*
50  * Translate a kernel virtual address to a physical address by walking
51  * the kernels page table.
52  */
53 
54 /* Stolen from sys/arch/sh/include/pmap.h we can't really include */
55 #define	__PMAP_PTP_N		512	/* # of page table page maps 2GB. */
56 /* Stolen from sys/arch/sh/sh/pmap.c */
57 #define	__PMAP_PTP_SHIFT	22
58 #define	__PMAP_PTP_PG_N		(PAGE_SIZE / sizeof(pt_entry_t))
59 #define	__PMAP_PTP_INDEX(va)	(((va) >> __PMAP_PTP_SHIFT) & (__PMAP_PTP_N - 1))
60 #define	__PMAP_PTP_OFSET(va)	((va >> PGSHIFT) & (__PMAP_PTP_PG_N - 1))
61 
62 int
63 _kvm_kvatop(kvm_t *kd, u_long va, paddr_t *pa)
64 {
65 	cpu_kcore_hdr_t *h = kd->cpu_data;
66 	u_int l1idx, l2idx;
67 	vaddr_t l2va;
68 	pt_entry_t l1pte, l2pte;
69 	off_t pteoffset;
70 
71 	if (ISALIVE(kd)) {
72 		_kvm_err(kd, 0, "vatop called in live kernel!");
73 		return (0);
74 	}
75 
76 	/*
77 	 * P1 and P2 segments addresses are trivial.
78 	 */
79 	if (va >= SH3_P1SEG_BASE && va <= SH3_P1SEG_END) {
80 		*pa = SH3_P1SEG_TO_PHYS(va);
81 		return (int)((vaddr_t)SH3_P1SEG_END + 1 - va);
82 	}
83 	if (va >= SH3_P2SEG_BASE && va <= SH3_P2SEG_END) {
84 		*pa = SH3_P2SEG_TO_PHYS(va);
85 		return (int)((vaddr_t)SH3_P2SEG_END + 1 - va);
86 	}
87 
88 	/*
89 	 * P3 segment addresses need kernel page table walk.
90 	 */
91 	if (va >= SH3_P3SEG_BASE && va < SH3_P3SEG_END) {
92 		l1idx = __PMAP_PTP_INDEX(va - VM_MIN_KERNEL_ADDRESS);
93 		l2idx = __PMAP_PTP_OFSET(va);
94 
95 		/* read level 1 pte */
96 		pteoffset = h->kcore_kptp + sizeof(pt_entry_t) * l1idx;
97 		if (_kvm_pread(kd, kd->pmfd, (char *)&l1pte, sizeof(l1pte),
98 		    _kvm_pa2off(kd, pteoffset)) != sizeof(l1pte)) {
99 			_kvm_syserr(kd, 0, "could not read level 1 pte");
100 			goto bad;
101 		}
102 
103 		/* check pte for validity */
104 		if ((l1pte & PG_V) == 0) {
105 			_kvm_err(kd, 0, "invalid level 1 pte: no valid bit");
106 			goto bad;
107 		}
108 
109 		l2va = l1pte & PG_PPN;
110 		if (l2va < SH3_P1SEG_BASE || l2va > SH3_P1SEG_END) {
111 			_kvm_err(kd, 0, "invalid level 1 pte: out of P1");
112 			goto bad;
113 		}
114 
115 		/* read level 2 pte */
116 		pteoffset = SH3_P1SEG_TO_PHYS(l2va) +
117 		    sizeof(pt_entry_t) * l2idx;
118 		if (_kvm_pread(kd, kd->pmfd, (char *)&l2pte, sizeof(l2pte),
119 		    _kvm_pa2off(kd, pteoffset)) != sizeof(l2pte)) {
120 			_kvm_syserr(kd, 0, "could not read level 2 pte");
121 			goto bad;
122 		}
123 
124 		/* check pte for validity */
125 		if ((l2pte & PG_V) == 0) {
126 			_kvm_err(kd, 0, "invalid level 2 pte: no valid bit");
127 			goto bad;
128 		}
129 
130 		*pa = (l2pte & PG_PPN) | (va & PAGE_MASK);
131 		return (PAGE_SIZE - (va & PAGE_MASK));
132 	}
133 
134 	/*
135 	 * All other addresses are incorrect.
136 	 */
137 	_kvm_err(kd, 0, "not a kernel virtual address");
138 bad:
139 	*pa = (paddr_t)-1;
140 	return (0);
141 }
142 
143 /*
144  * Translate a physical address to a file offset in the crash dump.
145  */
146 off_t
147 _kvm_pa2off(kvm_t *kd, paddr_t pa)
148 {
149 	cpu_kcore_hdr_t *h = kd->cpu_data;
150 	phys_ram_seg_t *seg = h->kcore_segs;
151 	off_t off = kd->dump_off;
152 	u_int i;
153 
154 	for (i = h->kcore_nsegs; i != 0; i--) {
155 		if (pa >= seg->start && pa < seg->start + seg->size)
156 			return (off + (pa - seg->start));
157 		off += seg->size;
158 	}
159 
160 	_kvm_err(kd, 0, "physical address out of the image (%lx)", pa);
161 	return (0);
162 }
163