KVM: arm/arm64: vgic: Add vgic_{get,set}_phys_irq_active

In order to control the active state of an interrupt, introduce
a pair of accessors allowing the state to be set/queried.

This only affects the logical state, and the HW state will only be
applied at world-switch time.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

include/kvm/arm_vgic.h

@@ -356,6 +356,8 @@ int kvm_vgic_vcpu_active_irq(struct kvm_vcpu *vcpu);
 struct irq_phys_map *kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu,
 					   int virt_irq, int irq);
 int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, struct irq_phys_map *map);
+bool kvm_vgic_get_phys_irq_active(struct irq_phys_map *map);
+void kvm_vgic_set_phys_irq_active(struct irq_phys_map *map, bool active);
 
 #define irqchip_in_kernel(k)	(!!((k)->arch.vgic.in_kernel))
 #define vgic_initialized(k)	(!!((k)->arch.vgic.nr_cpus))

virt/kvm/arm/vgic.c

@@ -1801,6 +1801,30 @@ static void vgic_free_phys_irq_map_rcu(struct rcu_head *rcu)
 	kfree(entry);
 }
 
+/**
+ * kvm_vgic_get_phys_irq_active - Return the active state of a mapped IRQ
+ *
+ * Return the logical active state of a mapped interrupt. This doesn't
+ * necessarily reflects the current HW state.
+ */
+bool kvm_vgic_get_phys_irq_active(struct irq_phys_map *map)
+{
+	BUG_ON(!map);
+	return map->active;
+}
+
+/**
+ * kvm_vgic_set_phys_irq_active - Set the active state of a mapped IRQ
+ *
+ * Set the logical active state of a mapped interrupt. This doesn't
+ * immediately affects the HW state.
+ */
+void kvm_vgic_set_phys_irq_active(struct irq_phys_map *map, bool active)
+{
+	BUG_ON(!map);
+	map->active = active;
+}
+
 /**
  * kvm_vgic_unmap_phys_irq - Remove a virtual to physical IRQ mapping
  * @vcpu: The VCPU pointer