KVM: in-kernel IOAPIC save and restore support

This patch adds support for in-kernel ioapic save and restore (to
and from userspace). It uses the same get/set_irqchip ioctl as
in-kernel PIC.

Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/irq.h b/drivers/kvm/irq.h
index 4034f65..30adddc 100644
--- a/drivers/kvm/irq.h
+++ b/drivers/kvm/irq.h
@@ -61,7 +61,7 @@
 int kvm_cpu_has_interrupt(struct kvm_vcpu *v);
 void kvm_pic_update_irq(struct kvm_pic *s);
 
-#define IOAPIC_NUM_PINS  24
+#define IOAPIC_NUM_PINS  KVM_IOAPIC_NUM_PINS
 #define IOAPIC_VERSION_ID 0x11	/* IOAPIC version */
 #define IOAPIC_EDGE_TRIG  0
 #define IOAPIC_LEVEL_TRIG 1
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index c270e4a..61dff55 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -913,6 +913,11 @@
 			&pic_irqchip(kvm)->pics[1],
 			sizeof(struct kvm_pic_state));
 		break;
+	case KVM_IRQCHIP_IOAPIC:
+		memcpy (&chip->chip.ioapic,
+			ioapic_irqchip(kvm),
+			sizeof(struct kvm_ioapic_state));
+		break;
 	default:
 		r = -EINVAL;
 		break;
@@ -936,6 +941,11 @@
 			&chip->chip.pic,
 			sizeof(struct kvm_pic_state));
 		break;
+	case KVM_IRQCHIP_IOAPIC:
+		memcpy (ioapic_irqchip(kvm),
+			&chip->chip.ioapic,
+			sizeof(struct kvm_ioapic_state));
+		break;
 	default:
 		r = -EINVAL;
 		break;