aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/kvm/emulate.c
blob: 9046b53d87c198bb61890a8aefe08bf7a7b0660b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
/*
 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

#include <linux/mm.h>
#include <linux/kvm_host.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_emulate.h>
#include <asm/opcodes.h>
#include <trace/events/kvm.h>

#include "trace.h"

#define VCPU_NR_MODES		6
#define VCPU_REG_OFFSET_USR	0
#define VCPU_REG_OFFSET_FIQ	1
#define VCPU_REG_OFFSET_IRQ	2
#define VCPU_REG_OFFSET_SVC	3
#define VCPU_REG_OFFSET_ABT	4
#define VCPU_REG_OFFSET_UND	5
#define REG_OFFSET(_reg) \
	(offsetof(struct kvm_regs, _reg) / sizeof(u32))

#define USR_REG_OFFSET(_num) REG_OFFSET(usr_regs.uregs[_num])

static const unsigned long vcpu_reg_offsets[VCPU_NR_MODES][15] = {
	/* USR/SYS Registers */
	[VCPU_REG_OFFSET_USR] = {
		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
		USR_REG_OFFSET(12), USR_REG_OFFSET(13),	USR_REG_OFFSET(14),
	},

	/* FIQ Registers */
	[VCPU_REG_OFFSET_FIQ] = {
		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
		USR_REG_OFFSET(6), USR_REG_OFFSET(7),
		REG_OFFSET(fiq_regs[0]), /* r8 */
		REG_OFFSET(fiq_regs[1]), /* r9 */
		REG_OFFSET(fiq_regs[2]), /* r10 */
		REG_OFFSET(fiq_regs[3]), /* r11 */
		REG_OFFSET(fiq_regs[4]), /* r12 */
		REG_OFFSET(fiq_regs[5]), /* r13 */
		REG_OFFSET(fiq_regs[6]), /* r14 */
	},

	/* IRQ Registers */
	[VCPU_REG_OFFSET_IRQ] = {
		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
		USR_REG_OFFSET(12),
		REG_OFFSET(irq_regs[0]), /* r13 */
		REG_OFFSET(irq_regs[1]), /* r14 */
	},

	/* SVC Registers */
	[VCPU_REG_OFFSET_SVC] = {
		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
		USR_REG_OFFSET(12),
		REG_OFFSET(svc_regs[0]), /* r13 */
		REG_OFFSET(svc_regs[1]), /* r14 */
	},

	/* ABT Registers */
	[VCPU_REG_OFFSET_ABT] = {
		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
		USR_REG_OFFSET(12),
		REG_OFFSET(abt_regs[0]), /* r13 */
		REG_OFFSET(abt_regs[1]), /* r14 */
	},

	/* UND Registers */
	[VCPU_REG_OFFSET_UND] = {
		USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
		USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
		USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
		USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
		USR_REG_OFFSET(12),
		REG_OFFSET(und_regs[0]), /* r13 */
		REG_OFFSET(und_regs[1]), /* r14 */
	},
};

/*
 * Return a pointer to the register number valid in the current mode of
 * the virtual CPU.
 */
unsigned long *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num)
{
	unsigned long *reg_array = (unsigned long *)&vcpu->arch.ctxt.gp_regs;
	unsigned long mode = *vcpu_cpsr(vcpu) & MODE_MASK;

	switch (mode) {
	case USR_MODE...SVC_MODE:
		mode &= ~MODE32_BIT; /* 0 ... 3 */
		break;

	case ABT_MODE:
		mode = VCPU_REG_OFFSET_ABT;
		break;

	case UND_MODE:
		mode = VCPU_REG_OFFSET_UND;
		break;

	case SYSTEM_MODE:
		mode = VCPU_REG_OFFSET_USR;
		break;

	default:
		BUG();
	}

	return reg_array + vcpu_reg_offsets[mode][reg_num];
}

/*
 * Return the SPSR for the current mode of the virtual CPU.
 */
unsigned long *__vcpu_spsr(struct kvm_vcpu *vcpu)
{
	unsigned long mode = *vcpu_cpsr(vcpu) & MODE_MASK;
	switch (mode) {
	case SVC_MODE:
		return &vcpu->arch.ctxt.gp_regs.KVM_ARM_SVC_spsr;
	case ABT_MODE:
		return &vcpu->arch.ctxt.gp_regs.KVM_ARM_ABT_spsr;
	case UND_MODE:
		return &vcpu->arch.ctxt.gp_regs.KVM_ARM_UND_spsr;
	case IRQ_MODE:
		return &vcpu->arch.ctxt.gp_regs.KVM_ARM_IRQ_spsr;
	case FIQ_MODE:
		return &vcpu->arch.ctxt.gp_regs.KVM_ARM_FIQ_spsr;
	default:
		BUG();
	}
}

/******************************************************************************
 * Inject exceptions into the guest
 */

/**
 * kvm_inject_vabt - inject an async abort / SError into the guest
 * @vcpu: The VCPU to receive the exception
 *
 * It is assumed that this code is called from the VCPU thread and that the
 * VCPU therefore is not currently executing guest code.
 */
void kvm_inject_vabt(struct kvm_vcpu *vcpu)
{
	*vcpu_hcr(vcpu) |= HCR_VA;
}