Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * irq.c: API for in kernel interrupt controller
4 * Copyright (c) 2007, Intel Corporation.
5 * Copyright 2009 Red Hat, Inc. and/or its affiliates.
6 *
7 * Authors:
8 * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
9 */
10
11#include <linux/export.h>
12#include <linux/kvm_host.h>
13
14#include "irq.h"
15#include "i8254.h"
16#include "x86.h"
17#include "xen.h"
18
19/*
20 * check if there are pending timer events
21 * to be processed.
22 */
23int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
24{
25 int r = 0;
26
27 if (lapic_in_kernel(vcpu))
28 r = apic_has_pending_timer(vcpu);
29 if (kvm_xen_timer_enabled(vcpu))
30 r += kvm_xen_has_pending_timer(vcpu);
31
32 return r;
33}
34
35/*
36 * check if there is a pending userspace external interrupt
37 */
38static int pending_userspace_extint(struct kvm_vcpu *v)
39{
40 return v->arch.pending_external_vector != -1;
41}
42
43/*
44 * check if there is pending interrupt from
45 * non-APIC source without intack.
46 */
47int kvm_cpu_has_extint(struct kvm_vcpu *v)
48{
49 /*
50 * FIXME: interrupt.injected represents an interrupt whose
51 * side-effects have already been applied (e.g. bit from IRR
52 * already moved to ISR). Therefore, it is incorrect to rely
53 * on interrupt.injected to know if there is a pending
54 * interrupt in the user-mode LAPIC.
55 * This leads to nVMX/nSVM not be able to distinguish
56 * if it should exit from L2 to L1 on EXTERNAL_INTERRUPT on
57 * pending interrupt or should re-inject an injected
58 * interrupt.
59 */
60 if (!lapic_in_kernel(v))
61 return v->arch.interrupt.injected;
62
63 if (kvm_xen_has_interrupt(v))
64 return 1;
65
66 if (!kvm_apic_accept_pic_intr(v))
67 return 0;
68
69 if (irqchip_split(v->kvm))
70 return pending_userspace_extint(v);
71 else
72 return v->kvm->arch.vpic->output;
73}
74
75/*
76 * check if there is injectable interrupt:
77 * when virtual interrupt delivery enabled,
78 * interrupt from apic will handled by hardware,
79 * we don't need to check it here.
80 */
81int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
82{
83 if (kvm_cpu_has_extint(v))
84 return 1;
85
86 if (!is_guest_mode(v) && kvm_vcpu_apicv_active(v))
87 return 0;
88
89 return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
90}
91EXPORT_SYMBOL_GPL(kvm_cpu_has_injectable_intr);
92
93/*
94 * check if there is pending interrupt without
95 * intack.
96 */
97int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
98{
99 if (kvm_cpu_has_extint(v))
100 return 1;
101
102 return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
103}
104EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
105
106/*
107 * Read pending interrupt(from non-APIC source)
108 * vector and intack.
109 */
110static int kvm_cpu_get_extint(struct kvm_vcpu *v)
111{
112 if (!kvm_cpu_has_extint(v)) {
113 WARN_ON(!lapic_in_kernel(v));
114 return -1;
115 }
116
117 if (!lapic_in_kernel(v))
118 return v->arch.interrupt.nr;
119
120 if (kvm_xen_has_interrupt(v))
121 return v->kvm->arch.xen.upcall_vector;
122
123 if (irqchip_split(v->kvm)) {
124 int vector = v->arch.pending_external_vector;
125
126 v->arch.pending_external_vector = -1;
127 return vector;
128 } else
129 return kvm_pic_read_irq(v->kvm); /* PIC */
130}
131
132/*
133 * Read pending interrupt vector and intack.
134 */
135int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
136{
137 int vector = kvm_cpu_get_extint(v);
138 if (vector != -1)
139 return vector; /* PIC */
140
141 return kvm_get_apic_interrupt(v); /* APIC */
142}
143EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
144
145void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
146{
147 if (lapic_in_kernel(vcpu))
148 kvm_inject_apic_timer_irqs(vcpu);
149 if (kvm_xen_timer_enabled(vcpu))
150 kvm_xen_inject_timer_irqs(vcpu);
151}
152
153void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
154{
155 __kvm_migrate_apic_timer(vcpu);
156 __kvm_migrate_pit_timer(vcpu);
157 static_call_cond(kvm_x86_migrate_timers)(vcpu);
158}
159
160bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args)
161{
162 bool resample = args->flags & KVM_IRQFD_FLAG_RESAMPLE;
163
164 return resample ? irqchip_kernel(kvm) : irqchip_in_kernel(kvm);
165}
166
167bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
168{
169 return irqchip_in_kernel(kvm);
170}
1/*
2 * irq.c: API for in kernel interrupt controller
3 * Copyright (c) 2007, Intel Corporation.
4 * Copyright 2009 Red Hat, Inc. and/or its affiliates.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
17 * Place - Suite 330, Boston, MA 02111-1307 USA.
18 * Authors:
19 * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
20 *
21 */
22
23#include <linux/module.h>
24#include <linux/kvm_host.h>
25
26#include "irq.h"
27#include "i8254.h"
28#include "x86.h"
29
30/*
31 * check if there are pending timer events
32 * to be processed.
33 */
34int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
35{
36 if (lapic_in_kernel(vcpu))
37 return apic_has_pending_timer(vcpu);
38
39 return 0;
40}
41EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
42
43/*
44 * check if there is a pending userspace external interrupt
45 */
46static int pending_userspace_extint(struct kvm_vcpu *v)
47{
48 return v->arch.pending_external_vector != -1;
49}
50
51/*
52 * check if there is pending interrupt from
53 * non-APIC source without intack.
54 */
55static int kvm_cpu_has_extint(struct kvm_vcpu *v)
56{
57 u8 accept = kvm_apic_accept_pic_intr(v);
58
59 if (accept) {
60 if (irqchip_split(v->kvm))
61 return pending_userspace_extint(v);
62 else
63 return pic_irqchip(v->kvm)->output;
64 } else
65 return 0;
66}
67
68/*
69 * check if there is injectable interrupt:
70 * when virtual interrupt delivery enabled,
71 * interrupt from apic will handled by hardware,
72 * we don't need to check it here.
73 */
74int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
75{
76 if (!lapic_in_kernel(v))
77 return v->arch.interrupt.pending;
78
79 if (kvm_cpu_has_extint(v))
80 return 1;
81
82 if (kvm_vcpu_apicv_active(v))
83 return 0;
84
85 return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
86}
87
88/*
89 * check if there is pending interrupt without
90 * intack.
91 */
92int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
93{
94 if (!lapic_in_kernel(v))
95 return v->arch.interrupt.pending;
96
97 if (kvm_cpu_has_extint(v))
98 return 1;
99
100 return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
101}
102EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
103
104/*
105 * Read pending interrupt(from non-APIC source)
106 * vector and intack.
107 */
108static int kvm_cpu_get_extint(struct kvm_vcpu *v)
109{
110 if (kvm_cpu_has_extint(v)) {
111 if (irqchip_split(v->kvm)) {
112 int vector = v->arch.pending_external_vector;
113
114 v->arch.pending_external_vector = -1;
115 return vector;
116 } else
117 return kvm_pic_read_irq(v->kvm); /* PIC */
118 } else
119 return -1;
120}
121
122/*
123 * Read pending interrupt vector and intack.
124 */
125int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
126{
127 int vector;
128
129 if (!lapic_in_kernel(v))
130 return v->arch.interrupt.nr;
131
132 vector = kvm_cpu_get_extint(v);
133
134 if (vector != -1)
135 return vector; /* PIC */
136
137 return kvm_get_apic_interrupt(v); /* APIC */
138}
139EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
140
141void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
142{
143 if (lapic_in_kernel(vcpu))
144 kvm_inject_apic_timer_irqs(vcpu);
145}
146EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
147
148void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
149{
150 __kvm_migrate_apic_timer(vcpu);
151 __kvm_migrate_pit_timer(vcpu);
152}