xref: /openbsd/lib/libkvm/kvm_sh.c (revision 4cfece93)
1 /*	$OpenBSD: kvm_sh.c,v 1.7 2020/06/28 09:45:12 kettenis 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 #include <sys/vnode.h>
24 
25 #include <unistd.h>
26 #include <stdlib.h>
27 #include <nlist.h>
28 #include <kvm.h>
29 
30 #include <db.h>
31 
32 #include "kvm_private.h"
33 
34 #include <machine/cpu.h>
35 #include <machine/kcore.h>
36 #include <machine/pte.h>
37 #include <machine/vmparam.h>
38 
39 void
40 _kvm_freevtop(kvm_t *kd)
41 {
42 }
43 
44 int
45 _kvm_initvtop(kvm_t *kd)
46 {
47 	return (0);
48 }
49 
50 /*
51  * Translate a kernel virtual address to a physical address by walking
52  * the kernel page tables.
53  */
54 
55 /* Stolen from sys/arch/sh/include/pmap.h we can't really include */
56 #define	__PMAP_PTP_N		512	/* # of page table page maps 2GB. */
57 /* Stolen from sys/arch/sh/sh/pmap.c */
58 #define	__PMAP_PTP_SHIFT	22
59 #define	__PMAP_PTP_PG_N		(kd->nbpg / sizeof(pt_entry_t))
60 #define	__PMAP_PTP_INDEX(va)	(((va) >> __PMAP_PTP_SHIFT) & (__PMAP_PTP_N - 1))
61 #define	__PMAP_PTP_OFSET(va)	((va / kd->nbpg) & (__PMAP_PTP_PG_N - 1))
62 
63 int
64 _kvm_kvatop(kvm_t *kd, u_long va, paddr_t *pa)
65 {
66 	cpu_kcore_hdr_t *h = kd->cpu_data;
67 	u_int l1idx, l2idx;
68 	vaddr_t l2va;
69 	pt_entry_t l1pte, l2pte;
70 	off_t pteoffset;
71 
72 	if (ISALIVE(kd)) {
73 		_kvm_err(kd, 0, "vatop called in live kernel!");
74 		return (0);
75 	}
76 
77 	/*
78 	 * P1 and P2 segments addresses are trivial.
79 	 */
80 	if (va >= SH3_P1SEG_BASE && va <= SH3_P1SEG_END) {
81 		*pa = SH3_P1SEG_TO_PHYS(va);
82 		return (int)((vaddr_t)SH3_P1SEG_END + 1 - va);
83 	}
84 	if (va >= SH3_P2SEG_BASE && va <= SH3_P2SEG_END) {
85 		*pa = SH3_P2SEG_TO_PHYS(va);
86 		return (int)((vaddr_t)SH3_P2SEG_END + 1 - va);
87 	}
88 
89 	/*
90 	 * P3 segment addresses need kernel page table walk.
91 	 */
92 	if (va >= SH3_P3SEG_BASE && va < SH3_P3SEG_END) {
93 		l1idx = __PMAP_PTP_INDEX(va - VM_MIN_KERNEL_ADDRESS);
94 		l2idx = __PMAP_PTP_OFSET(va);
95 
96 		/* read level 1 pte */
97 		pteoffset = h->kcore_kptp + sizeof(pt_entry_t) * l1idx;
98 		if (_kvm_pread(kd, kd->pmfd, (char *)&l1pte, sizeof(l1pte),
99 		    _kvm_pa2off(kd, pteoffset)) != sizeof(l1pte)) {
100 			_kvm_syserr(kd, 0, "could not read level 1 pte");
101 			goto bad;
102 		}
103 
104 		/* check pte for validity */
105 		if ((l1pte & PG_V) == 0) {
106 			_kvm_err(kd, 0, "invalid level 1 pte: no valid bit");
107 			goto bad;
108 		}
109 
110 		l2va = l1pte & PG_PPN;
111 		if (l2va < SH3_P1SEG_BASE || l2va > SH3_P1SEG_END) {
112 			_kvm_err(kd, 0, "invalid level 1 pte: out of P1");
113 			goto bad;
114 		}
115 
116 		/* read level 2 pte */
117 		pteoffset = SH3_P1SEG_TO_PHYS(l2va) +
118 		    sizeof(pt_entry_t) * l2idx;
119 		if (_kvm_pread(kd, kd->pmfd, (char *)&l2pte, sizeof(l2pte),
120 		    _kvm_pa2off(kd, pteoffset)) != sizeof(l2pte)) {
121 			_kvm_syserr(kd, 0, "could not read level 2 pte");
122 			goto bad;
123 		}
124 
125 		/* check pte for validity */
126 		if ((l2pte & PG_V) == 0) {
127 			_kvm_err(kd, 0, "invalid level 2 pte: no valid bit");
128 			goto bad;
129 		}
130 
131 		*pa = (l2pte & PG_PPN) | (va & (kd->nbpg - 1));
132 		return (kd->nbpg - (va & (kd->nbpg - 1)));
133 	}
134 
135 	/*
136 	 * All other addresses are incorrect.
137 	 */
138 	_kvm_err(kd, 0, "not a kernel virtual address");
139 bad:
140 	*pa = (paddr_t)-1;
141 	return (0);
142 }
143 
144 /*
145  * Translate a physical address to a file offset in the crash dump.
146  */
147 off_t
148 _kvm_pa2off(kvm_t *kd, paddr_t pa)
149 {
150 	cpu_kcore_hdr_t *h = kd->cpu_data;
151 	phys_ram_seg_t *seg = h->kcore_segs;
152 	off_t off = kd->dump_off;
153 	u_int i;
154 
155 	for (i = h->kcore_nsegs; i != 0; i--) {
156 		if (pa >= seg->start && pa < seg->start + seg->size)
157 			return (off + (pa - seg->start));
158 		off += seg->size;
159 	}
160 
161 	_kvm_err(kd, 0, "physical address out of the image (%lx)", pa);
162 	return (0);
163 }
164