tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
3 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2, as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
17 */
18
19#include <linux/kvm.h>
20#include <linux/kvm_host.h>
21#include <asm/kvm_emulate.h>
22#include <asm/kvm_coproc.h>
23#include <asm/kvm_mmu.h>
24#include <asm/kvm_psci.h>
25#include <trace/events/kvm.h>
26
27#include "trace.h"
28
29#include "trace.h"
30
31typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);
32
33static int handle_svc_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
34{
35 /* SVC called from Hyp mode should never get here */
36 kvm_debug("SVC called from Hyp mode shouldn't go here\n");
37 BUG();
38 return -EINVAL; /* Squash warning */
39}
40
41static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
42{
43 trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0),
44 kvm_vcpu_hvc_get_imm(vcpu));
45
46 if (kvm_psci_call(vcpu))
47 return 1;
48
49 kvm_inject_undefined(vcpu);
50 return 1;
51}
52
53static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
54{
55 if (kvm_psci_call(vcpu))
56 return 1;
57
58 kvm_inject_undefined(vcpu);
59 return 1;
60}
61
62static int handle_pabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
63{
64 /* The hypervisor should never cause aborts */
65 kvm_err("Prefetch Abort taken from Hyp mode at %#08lx (HSR: %#08x)\n",
66 kvm_vcpu_get_hfar(vcpu), kvm_vcpu_get_hsr(vcpu));
67 return -EFAULT;
68}
69
70static int handle_dabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
71{
72 /* This is either an error in the ws. code or an external abort */
73 kvm_err("Data Abort taken from Hyp mode at %#08lx (HSR: %#08x)\n",
74 kvm_vcpu_get_hfar(vcpu), kvm_vcpu_get_hsr(vcpu));
75 return -EFAULT;
76}
77
78/**
79 * kvm_handle_wfi - handle a wait-for-interrupts instruction executed by a guest
80 * @vcpu: the vcpu pointer
81 * @run: the kvm_run structure pointer
82 *
83 * Simply sets the wait_for_interrupts flag on the vcpu structure, which will
84 * halt execution of world-switches and schedule other host processes until
85 * there is an incoming IRQ or FIQ to the VM.
86 */
87static int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run)
88{
89 trace_kvm_wfi(*vcpu_pc(vcpu));
90 kvm_vcpu_block(vcpu);
91 return 1;
92}
93
94static exit_handle_fn arm_exit_handlers[] = {
95 [HSR_EC_WFI] = kvm_handle_wfi,
96 [HSR_EC_CP15_32] = kvm_handle_cp15_32,
97 [HSR_EC_CP15_64] = kvm_handle_cp15_64,
98 [HSR_EC_CP14_MR] = kvm_handle_cp14_access,
99 [HSR_EC_CP14_LS] = kvm_handle_cp14_load_store,
100 [HSR_EC_CP14_64] = kvm_handle_cp14_access,
101 [HSR_EC_CP_0_13] = kvm_handle_cp_0_13_access,
102 [HSR_EC_CP10_ID] = kvm_handle_cp10_id,
103 [HSR_EC_SVC_HYP] = handle_svc_hyp,
104 [HSR_EC_HVC] = handle_hvc,
105 [HSR_EC_SMC] = handle_smc,
106 [HSR_EC_IABT] = kvm_handle_guest_abort,
107 [HSR_EC_IABT_HYP] = handle_pabt_hyp,
108 [HSR_EC_DABT] = kvm_handle_guest_abort,
109 [HSR_EC_DABT_HYP] = handle_dabt_hyp,
110};
111
112static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
113{
114 u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
115
116 if (hsr_ec >= ARRAY_SIZE(arm_exit_handlers) ||
117 !arm_exit_handlers[hsr_ec]) {
118 kvm_err("Unknown exception class: hsr: %#08x\n",
119 (unsigned int)kvm_vcpu_get_hsr(vcpu));
120 BUG();
121 }
122
123 return arm_exit_handlers[hsr_ec];
124}
125
126/*
127 * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
128 * proper exit to userspace.
129 */
130int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
131 int exception_index)
132{
133 exit_handle_fn exit_handler;
134
135 switch (exception_index) {
136 case ARM_EXCEPTION_IRQ:
137 return 1;
138 case ARM_EXCEPTION_UNDEFINED:
139 kvm_err("Undefined exception in Hyp mode at: %#08lx\n",
140 kvm_vcpu_get_hyp_pc(vcpu));
141 BUG();
142 panic("KVM: Hypervisor undefined exception!\n");
143 case ARM_EXCEPTION_DATA_ABORT:
144 case ARM_EXCEPTION_PREF_ABORT:
145 case ARM_EXCEPTION_HVC:
146 /*
147 * See ARM ARM B1.14.1: "Hyp traps on instructions
148 * that fail their condition code check"
149 */
150 if (!kvm_condition_valid(vcpu)) {
151 kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
152 return 1;
153 }
154
155 exit_handler = kvm_get_exit_handler(vcpu);
156
157 return exit_handler(vcpu, run);
158 default:
159 kvm_pr_unimpl("Unsupported exception type: %d",
160 exception_index);
161 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
162 return 0;
163 }
164}