[PATCH v3 51/59] KVM: arm/arm64: GICv4: Add doorbell interrupt handling

Marc Zyngier
2017-07-31T17:27:30Z

When a vPE is not running, a VLPI being made pending results in a
doorbell interrupt being delivered. Let's handle this interrupt
and update the pending_last flag that indicates that VLPIs are
pending. The corresponding vcpu is also kicked into action.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
virt/kvm/arm/vgic/vgic-v4.c | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 534d3051a078..6af3cde6d7d4 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -21,6 +21,19 @@

#include "vgic.h"

+static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info)
+{
+ struct kvm_vcpu *vcpu = info;
+
+ if (!kvm_vgic_vcpu_pending_irq(vcpu)) {
+ vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last = true;
+ kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
+ kvm_vcpu_kick(vcpu);
+ }
+
+ return IRQ_HANDLED;
+}
+
int vgic_v4_init(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
@@ -57,16 +70,37 @@ int vgic_v4_init(struct kvm *kvm)
return ret;
}

+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ int irq = dist->its_vm.vpes[i]->irq;
+
+ ret = request_irq(irq, vgic_v4_doorbell_handler,
+ 0, "vcpu", vcpu);
+ if (ret) {
+ kvm_err("failed to allocate vcpu IRQ%d\n", irq);
+ dist->its_vm.nr_vpes = i;
+ break;
+ }
+ }
+
+ if (ret)
+ vgic_v4_teardown(kvm);
+
return ret;
}

void vgic_v4_teardown(struct kvm *kvm)
{
struct its_vm *its_vm = &kvm->arch.vgic.its_vm;
+ int i;

if (!its_vm->vpes)
return;

+ for (i = 0; i < its_vm->nr_vpes; i++) {
+ struct kvm_vcpu *vcpu = kvm_get_vcpu(kvm, i);
+ free_irq(its_vm->vpes[i]->irq, vcpu);
+ }
+
its_free_vcpu_irqs(its_vm);
kfree(its_vm->vpes);
its_vm->nr_vpes = 0;
--
2.11.0