summaryrefslogtreecommitdiffstats
path: root/arch/arm64/kvm/handle_exit.c
blob: 34b8bd0711e94295b3b8d629e2e032db8d8bce33 (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
/*
 * Copyright (C) 2012,2013 - ARM Ltd
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * Derived from arch/arm/kvm/handle_exit.c:
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_coproc.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_psci.h>

typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);

static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	int ret;

	ret = kvm_psci_call(vcpu);
	if (ret < 0) {
		kvm_inject_undefined(vcpu);
		return 1;
	}

	return ret;
}

static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	kvm_inject_undefined(vcpu);
	return 1;
}

/**
 * kvm_handle_wfx - handle a wait-for-interrupts or wait-for-event
 *		    instruction executed by a guest
 *
 * @vcpu:	the vcpu pointer
 *
 * WFE: Yield the CPU and come back to this vcpu when the scheduler
 * decides to.
 * WFI: Simply call kvm_vcpu_block(), which will halt execution of
 * world-switches and schedule other host processes until there is an
 * incoming IRQ or FIQ to the VM.
 */
static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	if (kvm_vcpu_get_hsr(vcpu) & ESR_EL2_EC_WFI_ISS_WFE)
		kvm_vcpu_on_spin(vcpu);
	else
		kvm_vcpu_block(vcpu);

	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));

	return 1;
}

static exit_handle_fn arm_exit_handlers[] = {
	[ESR_EL2_EC_WFI]	= kvm_handle_wfx,
	[ESR_EL2_EC_CP15_32]	= kvm_handle_cp15_32,
	[ESR_EL2_EC_CP15_64]	= kvm_handle_cp15_64,
	[ESR_EL2_EC_CP14_MR]	= kvm_handle_cp14_32,
	[ESR_EL2_EC_CP14_LS]	= kvm_handle_cp14_load_store,
	[ESR_EL2_EC_CP14_64]	= kvm_handle_cp14_64,
	[ESR_EL2_EC_HVC32]	= handle_hvc,
	[ESR_EL2_EC_SMC32]	= handle_smc,
	[ESR_EL2_EC_HVC64]	= handle_hvc,
	[ESR_EL2_EC_SMC64]	= handle_smc,
	[ESR_EL2_EC_SYS64]	= kvm_handle_sys_reg,
	[ESR_EL2_EC_IABT]	= kvm_handle_guest_abort,
	[ESR_EL2_EC_DABT]	= kvm_handle_guest_abort,
};

static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
{
	u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);

	if (hsr_ec >= ARRAY_SIZE(arm_exit_handlers) ||
	    !arm_exit_handlers[hsr_ec]) {
		kvm_err("Unknown exception class: hsr: %#08x\n",
			(unsigned int)kvm_vcpu_get_hsr(vcpu));
		BUG();
	}

	return arm_exit_handlers[hsr_ec];
}

/*
 * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
 * proper exit to userspace.
 */
int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
		       int exception_index)
{
	exit_handle_fn exit_handler;

	switch (exception_index) {
	case ARM_EXCEPTION_IRQ:
		return 1;
	case ARM_EXCEPTION_TRAP:
		/*
		 * See ARM ARM B1.14.1: "Hyp traps on instructions
		 * that fail their condition code check"
		 */
		if (!kvm_condition_valid(vcpu)) {
			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
			return 1;
		}

		exit_handler = kvm_get_exit_handler(vcpu);

		return exit_handler(vcpu, run);
	default:
		kvm_pr_unimpl("Unsupported exception type: %d",
			      exception_index);
		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
		return 0;
	}
}
OpenPOWER on IntegriCloud