| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * irq.c: API for in kernel interrupt controller |
| * Copyright (c) 2007, Intel Corporation. |
| * Copyright 2009 Red Hat, Inc. and/or its affiliates. |
| * |
| * Authors: |
| * Yaozu (Eddie) Dong <Eddie.dong@intel.com> |
| */ |
| |
| #include <linux/export.h> |
| #include <linux/kvm_host.h> |
| |
| #include "irq.h" |
| #include "i8254.h" |
| #include "x86.h" |
| #include "xen.h" |
| |
| /* |
| * check if there are pending timer events |
| * to be processed. |
| */ |
| int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) |
| { |
| int r = 0; |
| |
| if (lapic_in_kernel(vcpu)) |
| r = apic_has_pending_timer(vcpu); |
| if (kvm_xen_timer_enabled(vcpu)) |
| r += kvm_xen_has_pending_timer(vcpu); |
| |
| return r; |
| } |
| EXPORT_SYMBOL(kvm_cpu_has_pending_timer); |
| |
| /* |
| * check if there is a pending userspace external interrupt |
| */ |
| static int pending_userspace_extint(struct kvm_vcpu *v) |
| { |
| return v->arch.pending_external_vector != -1; |
| } |
| |
| /* |
| * check if there is pending interrupt from |
| * non-APIC source without intack. |
| */ |
| int kvm_cpu_has_extint(struct kvm_vcpu *v) |
| { |
| /* |
| * FIXME: interrupt.injected represents an interrupt whose |
| * side-effects have already been applied (e.g. bit from IRR |
| * already moved to ISR). Therefore, it is incorrect to rely |
| * on interrupt.injected to know if there is a pending |
| * interrupt in the user-mode LAPIC. |
| * This leads to nVMX/nSVM not be able to distinguish |
| * if it should exit from L2 to L1 on EXTERNAL_INTERRUPT on |
| * pending interrupt or should re-inject an injected |
| * interrupt. |
| */ |
| if (!lapic_in_kernel(v)) |
| return v->arch.interrupt.injected; |
| |
| if (kvm_xen_has_interrupt(v)) |
| return 1; |
| |
| if (!kvm_apic_accept_pic_intr(v)) |
| return 0; |
| |
| if (irqchip_split(v->kvm)) |
| return pending_userspace_extint(v); |
| else |
| return v->kvm->arch.vpic->output; |
| } |
| |
| /* |
| * check if there is injectable interrupt: |
| * when virtual interrupt delivery enabled, |
| * interrupt from apic will handled by hardware, |
| * we don't need to check it here. |
| */ |
| int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v) |
| { |
| if (kvm_cpu_has_extint(v)) |
| return 1; |
| |
| if (!is_guest_mode(v) && kvm_vcpu_apicv_active(v)) |
| return 0; |
| |
| return kvm_apic_has_interrupt(v) != -1; /* LAPIC */ |
| } |
| EXPORT_SYMBOL_GPL(kvm_cpu_has_injectable_intr); |
| |
| /* |
| * check if there is pending interrupt without |
| * intack. |
| */ |
| int kvm_cpu_has_interrupt(struct kvm_vcpu *v) |
| { |
| if (kvm_cpu_has_extint(v)) |
| return 1; |
| |
| return kvm_apic_has_interrupt(v) != -1; /* LAPIC */ |
| } |
| EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt); |
| |
| /* |
| * Read pending interrupt(from non-APIC source) |
| * vector and intack. |
| */ |
| static int kvm_cpu_get_extint(struct kvm_vcpu *v) |
| { |
| if (!kvm_cpu_has_extint(v)) { |
| WARN_ON(!lapic_in_kernel(v)); |
| return -1; |
| } |
| |
| if (!lapic_in_kernel(v)) |
| return v->arch.interrupt.nr; |
| |
| if (kvm_xen_has_interrupt(v)) |
| return v->kvm->arch.xen.upcall_vector; |
| |
| if (irqchip_split(v->kvm)) { |
| int vector = v->arch.pending_external_vector; |
| |
| v->arch.pending_external_vector = -1; |
| return vector; |
| } else |
| return kvm_pic_read_irq(v->kvm); /* PIC */ |
| } |
| |
| /* |
| * Read pending interrupt vector and intack. |
| */ |
| int kvm_cpu_get_interrupt(struct kvm_vcpu *v) |
| { |
| int vector = kvm_cpu_get_extint(v); |
| if (vector != -1) |
| return vector; /* PIC */ |
| |
| return kvm_get_apic_interrupt(v); /* APIC */ |
| } |
| EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt); |
| |
| void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu) |
| { |
| if (lapic_in_kernel(vcpu)) |
| kvm_inject_apic_timer_irqs(vcpu); |
| if (kvm_xen_timer_enabled(vcpu)) |
| kvm_xen_inject_timer_irqs(vcpu); |
| } |
| EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs); |
| |
| void __kvm_migrate_timers(struct kvm_vcpu *vcpu) |
| { |
| __kvm_migrate_apic_timer(vcpu); |
| __kvm_migrate_pit_timer(vcpu); |
| static_call_cond(kvm_x86_migrate_timers)(vcpu); |
| } |
| |
| bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args) |
| { |
| bool resample = args->flags & KVM_IRQFD_FLAG_RESAMPLE; |
| |
| return resample ? irqchip_kernel(kvm) : irqchip_in_kernel(kvm); |
| } |