diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
new file mode 100644
index 0000000..d0169f5
--- /dev/null
+++ b/virt/kvm/irq_comm.c
@@ -0,0 +1,60 @@
+/*
+ * irq_comm.c: Common API for in kernel interrupt controller
+ * Copyright (c) 2007, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ * Authors:
+ *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
+ *
+ */
+
+#include <linux/kvm_host.h>
+#include "irq.h"
+
+#include "ioapic.h"
+
+/* This should be called with the kvm->lock mutex held */
+void kvm_set_irq(struct kvm *kvm, int irq, int level)
+{
+	/* Not possible to detect if the guest uses the PIC or the
+	 * IOAPIC.  So set the bit in both. The guest will ignore
+	 * writes to the unused one.
+	 */
+	kvm_ioapic_set_irq(kvm->arch.vioapic, irq, level);
+#ifdef CONFIG_X86
+	kvm_pic_set_irq(pic_irqchip(kvm), irq, level);
+#endif
+}
+
+void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi)
+{
+	struct kvm_irq_ack_notifier *kian;
+	struct hlist_node *n;
+
+	hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
+		if (kian->gsi == gsi)
+			kian->irq_acked(kian);
+}
+
+void kvm_register_irq_ack_notifier(struct kvm *kvm,
+				   struct kvm_irq_ack_notifier *kian)
+{
+	hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
+}
+
+void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
+				     struct kvm_irq_ack_notifier *kian)
+{
+	hlist_del(&kian->link);
+}