1 // SPDX-License-Identifier: GPL-2.0-only
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.
8 * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
11 #include <linux/export.h>
12 #include <linux/kvm_host.h>
19 * check if there are pending timer events
22 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
24 if (lapic_in_kernel(vcpu))
25 return apic_has_pending_timer(vcpu);
29 EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
32 * check if there is a pending userspace external interrupt
34 static int pending_userspace_extint(struct kvm_vcpu *v)
36 return v->arch.pending_external_vector != -1;
40 * check if there is pending interrupt from
41 * non-APIC source without intack.
43 int kvm_cpu_has_extint(struct kvm_vcpu *v)
46 * FIXME: interrupt.injected represents an interrupt whose
47 * side-effects have already been applied (e.g. bit from IRR
48 * already moved to ISR). Therefore, it is incorrect to rely
49 * on interrupt.injected to know if there is a pending
50 * interrupt in the user-mode LAPIC.
51 * This leads to nVMX/nSVM not be able to distinguish
52 * if it should exit from L2 to L1 on EXTERNAL_INTERRUPT on
53 * pending interrupt or should re-inject an injected
56 if (!lapic_in_kernel(v))
57 return v->arch.interrupt.injected;
59 if (!kvm_apic_accept_pic_intr(v))
62 if (irqchip_split(v->kvm))
63 return pending_userspace_extint(v);
65 return v->kvm->arch.vpic->output;
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.
74 int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
76 if (kvm_cpu_has_extint(v))
79 if (!is_guest_mode(v) && kvm_vcpu_apicv_active(v))
82 return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
86 * check if there is pending interrupt without
89 int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
91 if (kvm_cpu_has_extint(v))
94 return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
96 EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
99 * Read pending interrupt(from non-APIC source)
102 static int kvm_cpu_get_extint(struct kvm_vcpu *v)
104 if (!kvm_cpu_has_extint(v)) {
105 WARN_ON(!lapic_in_kernel(v));
109 if (!lapic_in_kernel(v))
110 return v->arch.interrupt.nr;
112 if (irqchip_split(v->kvm)) {
113 int vector = v->arch.pending_external_vector;
115 v->arch.pending_external_vector = -1;
118 return kvm_pic_read_irq(v->kvm); /* PIC */
122 * Read pending interrupt vector and intack.
124 int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
126 int vector = kvm_cpu_get_extint(v);
128 return vector; /* PIC */
130 return kvm_get_apic_interrupt(v); /* APIC */
132 EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
134 void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
136 if (lapic_in_kernel(vcpu))
137 kvm_inject_apic_timer_irqs(vcpu);
139 EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
141 void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
143 __kvm_migrate_apic_timer(vcpu);
144 __kvm_migrate_pit_timer(vcpu);
147 bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args)
149 bool resample = args->flags & KVM_IRQFD_FLAG_RESAMPLE;
151 return resample ? irqchip_kernel(kvm) : irqchip_in_kernel(kvm);