[PATCH 4/6] kvm: lapic: Add apicv activate/deactivate helper function

[Suthikulpanit, Suravee]

Introduce a helper function for setting lapic parameters when
activate/deactivate apicv.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 arch/x86/kvm/lapic.c | 23 ++++++++++++++++++-----
 arch/x86/kvm/lapic.h |  1 +
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 95295cf81283..9c5cd1a98928 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2126,6 +2126,22 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
 
 }
 
+void kvm_apic_update_apicv(struct kvm_vcpu *vcpu)
+{
+	struct kvm_lapic *apic = vcpu->arch.apic;
+	bool active = vcpu->arch.apicv_active;
+
+	if (active) {
+		/* irr_pending is always true when apicv is activated. */
+		apic->irr_pending = true;
+		apic->isr_count = 1;
+	} else {
+		apic->irr_pending = !!count_vectors(apic->regs + APIC_IRR);
+		apic->isr_count = count_vectors(apic->regs + APIC_ISR);
+	}
+}
+EXPORT_SYMBOL(kvm_apic_update_apicv);
+
 void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
 {
 	struct kvm_lapic *apic = vcpu->arch.apic;
@@ -2170,8 +2186,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
 		kvm_lapic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
 		kvm_lapic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
 	}
-	apic->irr_pending = vcpu->arch.apicv_active;
-	apic->isr_count = vcpu->arch.apicv_active ? 1 : 0;
+	kvm_apic_update_apicv(vcpu);
 	apic->highest_isr_cache = -1;
 	update_divide_count(apic);
 	atomic_set(&apic->lapic_timer.pending, 0);
@@ -2433,9 +2448,7 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
 	apic_manage_nmi_watchdog(apic, kvm_lapic_get_reg(apic, APIC_LVT0));
 	update_divide_count(apic);
 	start_apic_timer(apic);
-	apic->irr_pending = true;
-	apic->isr_count = vcpu->arch.apicv_active ?
-				1 : count_vectors(apic->regs + APIC_ISR);
+	kvm_apic_update_apicv(vcpu);
 	apic->highest_isr_cache = -1;
 	if (vcpu->arch.apicv_active) {
 		kvm_x86_ops->apicv_post_state_restore(vcpu);
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index ff6ef9c3d760..b657605cfec0 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -88,6 +88,7 @@ void kvm_apic_update_ppr(struct kvm_vcpu *vcpu);
 int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
 		     struct dest_map *dest_map);
 int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type);
+void kvm_apic_update_apicv(struct kvm_vcpu *vcpu);
 
 bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
 		struct kvm_lapic_irq *irq, int *r, struct dest_map *dest_map);
-- 
2.17.1