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