kvm: x86: move ioapic.c and irq_comm.c back to arch/x86/

ia64 does not need them anymore.  Ack notifiers become x86-specific
too.

Suggested-by: Gleb Natapov <gleb@kernel.org>
Reviewed-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

6 files changed, 1150 insertions, 3 deletions

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 769db36a3001..76ff3e2d8fd2 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -603,6 +603,9 @@ struct kvm_arch {
 
 	struct kvm_xen_hvm_config xen_hvm_config;
 
+	/* reads protected by irq_srcu, writes by irq_lock */
+	struct hlist_head mask_notifier_list;
+
 	/* fields used by HYPER-V emulation */
 	u64 hv_guest_os_id;
 	u64 hv_hypercall;
@@ -819,6 +822,19 @@ int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
 			  const void *val, int bytes);
 u8 kvm_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn);
 
+struct kvm_irq_mask_notifier {
+	void (*func)(struct kvm_irq_mask_notifier *kimn, bool masked);
+	int irq;
+	struct hlist_node link;
+};
+
+void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
+				    struct kvm_irq_mask_notifier *kimn);
+void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
+				      struct kvm_irq_mask_notifier *kimn);
+void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
+			     bool mask);
+
 extern bool tdp_enabled;
 
 u64 vcpu_tsc_khz(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 25d22b2d6509..ee1cd92b03be 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -7,14 +7,13 @@ CFLAGS_vmx.o := -I.
 
 KVM := ../../../virt/kvm
 
-kvm-y			+= $(KVM)/kvm_main.o $(KVM)/ioapic.o \
-				$(KVM)/coalesced_mmio.o $(KVM)/irq_comm.o \
+kvm-y			+= $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o \
 				$(KVM)/eventfd.o $(KVM)/irqchip.o $(KVM)/vfio.o
 kvm-$(CONFIG_KVM_DEVICE_ASSIGNMENT)	+= $(KVM)/assigned-dev.o $(KVM)/iommu.o
 kvm-$(CONFIG_KVM_ASYNC_PF)	+= $(KVM)/async_pf.o
 
 kvm-y			+= x86.o mmu.o emulate.o i8259.o irq.o lapic.o \
-			   i8254.o cpuid.o pmu.o
+			   i8254.o ioapic.o irq_comm.o cpuid.o pmu.o
 kvm-intel-y		+= vmx.o
 kvm-amd-y		+= svm.o
 
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
new file mode 100644
index 000000000000..f0f7ef82b7a6
--- /dev/null
+++ b/arch/x86/kvm/ioapic.c
@@ -0,0 +1,682 @@
+/*
+ *  Copyright (C) 2001  MandrakeSoft S.A.
+ *  Copyright 2010 Red Hat, Inc. and/or its affiliates.
+ *
+ *    MandrakeSoft S.A.
+ *    43, rue d'Aboukir
+ *    75002 Paris - France
+ *    http://www.linux-mandrake.com/
+ *    http://www.mandrakesoft.com/
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ *  Yunhong Jiang <yunhong.jiang@intel.com>
+ *  Yaozu (Eddie) Dong <eddie.dong@intel.com>
+ *  Based on Xen 3.1 code.
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/kvm.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/smp.h>
+#include <linux/hrtimer.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+#include <asm/current.h>
+#include <trace/events/kvm.h>
+
+#include "ioapic.h"
+#include "lapic.h"
+#include "irq.h"
+
+#if 0
+#define ioapic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg)
+#else
+#define ioapic_debug(fmt, arg...)
+#endif
+static int ioapic_service(struct kvm_ioapic *vioapic, int irq,
+		bool line_status);
+
+static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic,
+					  unsigned long addr,
+					  unsigned long length)
+{
+	unsigned long result = 0;
+
+	switch (ioapic->ioregsel) {
+	case IOAPIC_REG_VERSION:
+		result = ((((IOAPIC_NUM_PINS - 1) & 0xff) << 16)
+			  | (IOAPIC_VERSION_ID & 0xff));
+		break;
+
+	case IOAPIC_REG_APIC_ID:
+	case IOAPIC_REG_ARB_ID:
+		result = ((ioapic->id & 0xf) << 24);
+		break;
+
+	default:
+		{
+			u32 redir_index = (ioapic->ioregsel - 0x10) >> 1;
+			u64 redir_content;
+
+			if (redir_index < IOAPIC_NUM_PINS)
+				redir_content =
+					ioapic->redirtbl[redir_index].bits;
+			else
+				redir_content = ~0ULL;
+
+			result = (ioapic->ioregsel & 0x1) ?
+			    (redir_content >> 32) & 0xffffffff :
+			    redir_content & 0xffffffff;
+			break;
+		}
+	}
+
+	return result;
+}
+
+static void rtc_irq_eoi_tracking_reset(struct kvm_ioapic *ioapic)
+{
+	ioapic->rtc_status.pending_eoi = 0;
+	bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
+}
+
+static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic);
+
+static void rtc_status_pending_eoi_check_valid(struct kvm_ioapic *ioapic)
+{
+	if (WARN_ON(ioapic->rtc_status.pending_eoi < 0))
+		kvm_rtc_eoi_tracking_restore_all(ioapic);
+}
+
+static void __rtc_irq_eoi_tracking_restore_one(struct kvm_vcpu *vcpu)
+{
+	bool new_val, old_val;
+	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
+	union kvm_ioapic_redirect_entry *e;
+
+	e = &ioapic->redirtbl[RTC_GSI];
+	if (!kvm_apic_match_dest(vcpu, NULL, 0,	e->fields.dest_id,
+				e->fields.dest_mode))
+		return;
+
+	new_val = kvm_apic_pending_eoi(vcpu, e->fields.vector);
+	old_val = test_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
+
+	if (new_val == old_val)
+		return;
+
+	if (new_val) {
+		__set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
+		ioapic->rtc_status.pending_eoi++;
+	} else {
+		__clear_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
+		ioapic->rtc_status.pending_eoi--;
+		rtc_status_pending_eoi_check_valid(ioapic);
+	}
+}
+
+void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu)
+{
+	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
+
+	spin_lock(&ioapic->lock);
+	__rtc_irq_eoi_tracking_restore_one(vcpu);
+	spin_unlock(&ioapic->lock);
+}
+
+static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic)
+{
+	struct kvm_vcpu *vcpu;
+	int i;
+
+	if (RTC_GSI >= IOAPIC_NUM_PINS)
+		return;
+
+	rtc_irq_eoi_tracking_reset(ioapic);
+	kvm_for_each_vcpu(i, vcpu, ioapic->kvm)
+	    __rtc_irq_eoi_tracking_restore_one(vcpu);
+}
+
+static void rtc_irq_eoi(struct kvm_ioapic *ioapic, struct kvm_vcpu *vcpu)
+{
+	if (test_and_clear_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map)) {
+		--ioapic->rtc_status.pending_eoi;
+		rtc_status_pending_eoi_check_valid(ioapic);
+	}
+}
+
+static bool rtc_irq_check_coalesced(struct kvm_ioapic *ioapic)
+{
+	if (ioapic->rtc_status.pending_eoi > 0)
+		return true; /* coalesced */
+
+	return false;
+}
+
+static int ioapic_set_irq(struct kvm_ioapic *ioapic, unsigned int irq,
+		int irq_level, bool line_status)
+{
+	union kvm_ioapic_redirect_entry entry;
+	u32 mask = 1 << irq;
+	u32 old_irr;
+	int edge, ret;
+
+	entry = ioapic->redirtbl[irq];
+	edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
+
+	if (!irq_level) {
+		ioapic->irr &= ~mask;
+		ret = 1;
+		goto out;
+	}
+
+	/*
+	 * Return 0 for coalesced interrupts; for edge-triggered interrupts,
+	 * this only happens if a previous edge has not been delivered due
+	 * do masking.  For level interrupts, the remote_irr field tells
+	 * us if the interrupt is waiting for an EOI.
+	 *
+	 * RTC is special: it is edge-triggered, but userspace likes to know
+	 * if it has been already ack-ed via EOI because coalesced RTC
+	 * interrupts lead to time drift in Windows guests.  So we track
+	 * EOI manually for the RTC interrupt.
+	 */
+	if (irq == RTC_GSI && line_status &&
+		rtc_irq_check_coalesced(ioapic)) {
+		ret = 0;
+		goto out;
+	}
+
+	old_irr = ioapic->irr;
+	ioapic->irr |= mask;
+	if ((edge && old_irr == ioapic->irr) ||
+	    (!edge && entry.fields.remote_irr)) {
+		ret = 0;
+		goto out;
+	}
+
+	ret = ioapic_service(ioapic, irq, line_status);
+
+out:
+	trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
+	return ret;
+}
+
+static void kvm_ioapic_inject_all(struct kvm_ioapic *ioapic, unsigned long irr)
+{
+	u32 idx;
+
+	rtc_irq_eoi_tracking_reset(ioapic);
+	for_each_set_bit(idx, &irr, IOAPIC_NUM_PINS)
+		ioapic_set_irq(ioapic, idx, 1, true);
+
+	kvm_rtc_eoi_tracking_restore_all(ioapic);
+}
+
+
+static void update_handled_vectors(struct kvm_ioapic *ioapic)
+{
+	DECLARE_BITMAP(handled_vectors, 256);
+	int i;
+
+	memset(handled_vectors, 0, sizeof(handled_vectors));
+	for (i = 0; i < IOAPIC_NUM_PINS; ++i)
+		__set_bit(ioapic->redirtbl[i].fields.vector, handled_vectors);
+	memcpy(ioapic->handled_vectors, handled_vectors,
+	       sizeof(handled_vectors));
+	smp_wmb();
+}
+
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
+			u32 *tmr)
+{
+	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
+	union kvm_ioapic_redirect_entry *e;
+	int index;
+
+	spin_lock(&ioapic->lock);
+	for (index = 0; index < IOAPIC_NUM_PINS; index++) {
+		e = &ioapic->redirtbl[index];
+		if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG ||
+		    kvm_irq_has_notifier(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index) ||
+		    index == RTC_GSI) {
+			if (kvm_apic_match_dest(vcpu, NULL, 0,
+				e->fields.dest_id, e->fields.dest_mode)) {
+				__set_bit(e->fields.vector,
+					(unsigned long *)eoi_exit_bitmap);
+				if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG)
+					__set_bit(e->fields.vector,
+						(unsigned long *)tmr);
+			}
+		}
+	}
+	spin_unlock(&ioapic->lock);
+}
+
+#ifdef CONFIG_X86
+void kvm_vcpu_request_scan_ioapic(struct kvm *kvm)
+{
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+
+	if (!ioapic)
+		return;
+	kvm_make_scan_ioapic_request(kvm);
+}
+#else
+void kvm_vcpu_request_scan_ioapic(struct kvm *kvm)
+{
+	return;
+}
+#endif
+
+static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
+{
+	unsigned index;
+	bool mask_before, mask_after;
+	union kvm_ioapic_redirect_entry *e;
+
+	switch (ioapic->ioregsel) {
+	case IOAPIC_REG_VERSION:
+		/* Writes are ignored. */
+		break;
+
+	case IOAPIC_REG_APIC_ID:
+		ioapic->id = (val >> 24) & 0xf;
+		break;
+
+	case IOAPIC_REG_ARB_ID:
+		break;
+
+	default:
+		index = (ioapic->ioregsel - 0x10) >> 1;
+
+		ioapic_debug("change redir index %x val %x\n", index, val);
+		if (index >= IOAPIC_NUM_PINS)
+			return;
+		e = &ioapic->redirtbl[index];
+		mask_before = e->fields.mask;
+		if (ioapic->ioregsel & 1) {
+			e->bits &= 0xffffffff;
+			e->bits |= (u64) val << 32;
+		} else {
+			e->bits &= ~0xffffffffULL;
+			e->bits |= (u32) val;
+			e->fields.remote_irr = 0;
+		}
+		update_handled_vectors(ioapic);
+		mask_after = e->fields.mask;
+		if (mask_before != mask_after)
+			kvm_fire_mask_notifiers(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index, mask_after);
+		if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG
+		    && ioapic->irr & (1 << index))
+			ioapic_service(ioapic, index, false);
+		kvm_vcpu_request_scan_ioapic(ioapic->kvm);
+		break;
+	}
+}
+
+static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
+{
+	union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
+	struct kvm_lapic_irq irqe;
+	int ret;
+
+	if (entry->fields.mask)
+		return -1;
+
+	ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
+		     "vector=%x trig_mode=%x\n",
+		     entry->fields.dest_id, entry->fields.dest_mode,
+		     entry->fields.delivery_mode, entry->fields.vector,
+		     entry->fields.trig_mode);
+
+	irqe.dest_id = entry->fields.dest_id;
+	irqe.vector = entry->fields.vector;
+	irqe.dest_mode = entry->fields.dest_mode;
+	irqe.trig_mode = entry->fields.trig_mode;
+	irqe.delivery_mode = entry->fields.delivery_mode << 8;
+	irqe.level = 1;
+	irqe.shorthand = 0;
+
+	if (irqe.trig_mode == IOAPIC_EDGE_TRIG)
+		ioapic->irr &= ~(1 << irq);
+
+	if (irq == RTC_GSI && line_status) {
+		/*
+		 * pending_eoi cannot ever become negative (see
+		 * rtc_status_pending_eoi_check_valid) and the caller
+		 * ensures that it is only called if it is >= zero, namely
+		 * if rtc_irq_check_coalesced returns false).
+		 */
+		BUG_ON(ioapic->rtc_status.pending_eoi != 0);
+		ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe,
+				ioapic->rtc_status.dest_map);
+		ioapic->rtc_status.pending_eoi = (ret < 0 ? 0 : ret);
+	} else
+		ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe, NULL);
+
+	if (ret && irqe.trig_mode == IOAPIC_LEVEL_TRIG)
+		entry->fields.remote_irr = 1;
+
+	return ret;
+}
+
+int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
+		       int level, bool line_status)
+{
+	int ret, irq_level;
+
+	BUG_ON(irq < 0 || irq >= IOAPIC_NUM_PINS);
+
+	spin_lock(&ioapic->lock);
+	irq_level = __kvm_irq_line_state(&ioapic->irq_states[irq],
+					 irq_source_id, level);
+	ret = ioapic_set_irq(ioapic, irq, irq_level, line_status);
+
+	spin_unlock(&ioapic->lock);
+
+	return ret;
+}
+
+void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id)
+{
+	int i;
+
+	spin_lock(&ioapic->lock);
+	for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
+		__clear_bit(irq_source_id, &ioapic->irq_states[i]);
+	spin_unlock(&ioapic->lock);
+}
+
+static void kvm_ioapic_eoi_inject_work(struct work_struct *work)
+{
+	int i;
+	struct kvm_ioapic *ioapic = container_of(work, struct kvm_ioapic,
+						 eoi_inject.work);
+	spin_lock(&ioapic->lock);
+	for (i = 0; i < IOAPIC_NUM_PINS; i++) {
+		union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
+
+		if (ent->fields.trig_mode != IOAPIC_LEVEL_TRIG)
+			continue;
+
+		if (ioapic->irr & (1 << i) && !ent->fields.remote_irr)
+			ioapic_service(ioapic, i, false);
+	}
+	spin_unlock(&ioapic->lock);
+}
+
+#define IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT 10000
+
+static void __kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu,
+			struct kvm_ioapic *ioapic, int vector, int trigger_mode)
+{
+	int i;
+
+	for (i = 0; i < IOAPIC_NUM_PINS; i++) {
+		union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
+
+		if (ent->fields.vector != vector)
+			continue;
+
+		if (i == RTC_GSI)
+			rtc_irq_eoi(ioapic, vcpu);
+		/*
+		 * We are dropping lock while calling ack notifiers because ack
+		 * notifier callbacks for assigned devices call into IOAPIC
+		 * recursively. Since remote_irr is cleared only after call
+		 * to notifiers if the same vector will be delivered while lock
+		 * is dropped it will be put into irr and will be delivered
+		 * after ack notifier returns.
+		 */
+		spin_unlock(&ioapic->lock);
+		kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, i);
+		spin_lock(&ioapic->lock);
+
+		if (trigger_mode != IOAPIC_LEVEL_TRIG)
+			continue;
+
+		ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
+		ent->fields.remote_irr = 0;
+		if (!ent->fields.mask && (ioapic->irr & (1 << i))) {
+			++ioapic->irq_eoi[i];
+			if (ioapic->irq_eoi[i] == IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT) {
+				/*
+				 * Real hardware does not deliver the interrupt
+				 * immediately during eoi broadcast, and this
+				 * lets a buggy guest make slow progress
+				 * even if it does not correctly handle a
+				 * level-triggered interrupt.  Emulate this
+				 * behavior if we detect an interrupt storm.
+				 */
+				schedule_delayed_work(&ioapic->eoi_inject, HZ / 100);
+				ioapic->irq_eoi[i] = 0;
+				trace_kvm_ioapic_delayed_eoi_inj(ent->bits);
+			} else {
+				ioapic_service(ioapic, i, false);
+			}
+		} else {
+			ioapic->irq_eoi[i] = 0;
+		}
+	}
+}
+
+bool kvm_ioapic_handles_vector(struct kvm *kvm, int vector)
+{
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+	smp_rmb();
+	return test_bit(vector, ioapic->handled_vectors);
+}
+
+void kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu, int vector, int trigger_mode)
+{
+	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
+
+	spin_lock(&ioapic->lock);
+	__kvm_ioapic_update_eoi(vcpu, ioapic, vector, trigger_mode);
+	spin_unlock(&ioapic->lock);
+}
+
+static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
+{
+	return container_of(dev, struct kvm_ioapic, dev);
+}
+
+static inline int ioapic_in_range(struct kvm_ioapic *ioapic, gpa_t addr)
+{
+	return ((addr >= ioapic->base_address &&
+		 (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
+}
+
+static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
+			    void *val)
+{
+	struct kvm_ioapic *ioapic = to_ioapic(this);
+	u32 result;
+	if (!ioapic_in_range(ioapic, addr))
+		return -EOPNOTSUPP;
+
+	ioapic_debug("addr %lx\n", (unsigned long)addr);
+	ASSERT(!(addr & 0xf));	/* check alignment */
+
+	addr &= 0xff;
+	spin_lock(&ioapic->lock);
+	switch (addr) {
+	case IOAPIC_REG_SELECT:
+		result = ioapic->ioregsel;
+		break;
+
+	case IOAPIC_REG_WINDOW:
+		result = ioapic_read_indirect(ioapic, addr, len);
+		break;
+
+	default:
+		result = 0;
+		break;
+	}
+	spin_unlock(&ioapic->lock);
+
+	switch (len) {
+	case 8:
+		*(u64 *) val = result;
+		break;
+	case 1:
+	case 2:
+	case 4:
+		memcpy(val, (char *)&result, len);
+		break;
+	default:
+		printk(KERN_WARNING "ioapic: wrong length %d\n", len);
+	}
+	return 0;
+}
+
+static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
+			     const void *val)
+{
+	struct kvm_ioapic *ioapic = to_ioapic(this);
+	u32 data;
+	if (!ioapic_in_range(ioapic, addr))
+		return -EOPNOTSUPP;
+
+	ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
+		     (void*)addr, len, val);
+	ASSERT(!(addr & 0xf));	/* check alignment */
+
+	switch (len) {
+	case 8:
+	case 4:
+		data = *(u32 *) val;
+		break;
+	case 2:
+		data = *(u16 *) val;
+		break;
+	case 1:
+		data = *(u8  *) val;
+		break;
+	default:
+		printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
+		return 0;
+	}
+
+	addr &= 0xff;
+	spin_lock(&ioapic->lock);
+	switch (addr) {
+	case IOAPIC_REG_SELECT:
+		ioapic->ioregsel = data & 0xFF; /* 8-bit register */
+		break;
+
+	case IOAPIC_REG_WINDOW:
+		ioapic_write_indirect(ioapic, data);
+		break;
+
+	default:
+		break;
+	}
+	spin_unlock(&ioapic->lock);
+	return 0;
+}
+
+static void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
+{
+	int i;
+
+	cancel_delayed_work_sync(&ioapic->eoi_inject);
+	for (i = 0; i < IOAPIC_NUM_PINS; i++)
+		ioapic->redirtbl[i].fields.mask = 1;
+	ioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
+	ioapic->ioregsel = 0;
+	ioapic->irr = 0;
+	ioapic->id = 0;
+	memset(ioapic->irq_eoi, 0x00, IOAPIC_NUM_PINS);
+	rtc_irq_eoi_tracking_reset(ioapic);
+	update_handled_vectors(ioapic);
+}
+
+static const struct kvm_io_device_ops ioapic_mmio_ops = {
+	.read     = ioapic_mmio_read,
+	.write    = ioapic_mmio_write,
+};
+
+int kvm_ioapic_init(struct kvm *kvm)
+{
+	struct kvm_ioapic *ioapic;
+	int ret;
+
+	ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
+	if (!ioapic)
+		return -ENOMEM;
+	spin_lock_init(&ioapic->lock);
+	INIT_DELAYED_WORK(&ioapic->eoi_inject, kvm_ioapic_eoi_inject_work);
+	kvm->arch.vioapic = ioapic;
+	kvm_ioapic_reset(ioapic);
+	kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
+	ioapic->kvm = kvm;
+	mutex_lock(&kvm->slots_lock);
+	ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, ioapic->base_address,
+				      IOAPIC_MEM_LENGTH, &ioapic->dev);
+	mutex_unlock(&kvm->slots_lock);
+	if (ret < 0) {
+		kvm->arch.vioapic = NULL;
+		kfree(ioapic);
+	}
+
+	return ret;
+}
+
+void kvm_ioapic_destroy(struct kvm *kvm)
+{
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+
+	cancel_delayed_work_sync(&ioapic->eoi_inject);
+	if (ioapic) {
+		kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
+		kvm->arch.vioapic = NULL;
+		kfree(ioapic);
+	}
+}
+
+int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
+{
+	struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
+	if (!ioapic)
+		return -EINVAL;
+
+	spin_lock(&ioapic->lock);
+	memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
+	spin_unlock(&ioapic->lock);
+	return 0;
+}
+
+int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
+{
+	struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
+	if (!ioapic)
+		return -EINVAL;
+
+	spin_lock(&ioapic->lock);
+	memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
+	ioapic->irr = 0;
+	update_handled_vectors(ioapic);
+	kvm_vcpu_request_scan_ioapic(kvm);
+	kvm_ioapic_inject_all(ioapic, state->irr);
+	spin_unlock(&ioapic->lock);
+	return 0;
+}
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
new file mode 100644
index 000000000000..deac8d509f2a
--- /dev/null
+++ b/arch/x86/kvm/ioapic.h
@@ -0,0 +1,102 @@
+#ifndef __KVM_IO_APIC_H
+#define __KVM_IO_APIC_H
+
+#include <linux/kvm_host.h>
+
+#include "iodev.h"
+
+struct kvm;
+struct kvm_vcpu;
+
+#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
+
+#define IOAPIC_DEFAULT_BASE_ADDRESS  0xfec00000
+#define IOAPIC_MEM_LENGTH            0x100
+
+/* Direct registers. */
+#define IOAPIC_REG_SELECT  0x00
+#define IOAPIC_REG_WINDOW  0x10
+
+/* Indirect registers. */
+#define IOAPIC_REG_APIC_ID 0x00	/* x86 IOAPIC only */
+#define IOAPIC_REG_VERSION 0x01
+#define IOAPIC_REG_ARB_ID  0x02	/* x86 IOAPIC only */
+
+/*ioapic delivery mode*/
+#define	IOAPIC_FIXED			0x0
+#define	IOAPIC_LOWEST_PRIORITY		0x1
+#define	IOAPIC_PMI			0x2
+#define	IOAPIC_NMI			0x4
+#define	IOAPIC_INIT			0x5
+#define	IOAPIC_EXTINT			0x7
+
+#ifdef CONFIG_X86
+#define RTC_GSI 8
+#else
+#define RTC_GSI -1U
+#endif
+
+struct rtc_status {
+	int pending_eoi;
+	DECLARE_BITMAP(dest_map, KVM_MAX_VCPUS);
+};
+
+struct kvm_ioapic {
+	u64 base_address;
+	u32 ioregsel;
+	u32 id;
+	u32 irr;
+	u32 pad;
+	union kvm_ioapic_redirect_entry redirtbl[IOAPIC_NUM_PINS];
+	unsigned long irq_states[IOAPIC_NUM_PINS];
+	struct kvm_io_device dev;
+	struct kvm *kvm;
+	void (*ack_notifier)(void *opaque, int irq);
+	spinlock_t lock;
+	DECLARE_BITMAP(handled_vectors, 256);
+	struct rtc_status rtc_status;
+	struct delayed_work eoi_inject;
+	u32 irq_eoi[IOAPIC_NUM_PINS];
+};
+
+#ifdef DEBUG
+#define ASSERT(x)  							\
+do {									\
+	if (!(x)) {							\
+		printk(KERN_EMERG "assertion failed %s: %d: %s\n",	\
+		       __FILE__, __LINE__, #x);				\
+		BUG();							\
+	}								\
+} while (0)
+#else
+#define ASSERT(x) do { } while (0)
+#endif
+
+static inline struct kvm_ioapic *ioapic_irqchip(struct kvm *kvm)
+{
+	return kvm->arch.vioapic;
+}
+
+void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu);
+int kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
+		int short_hand, unsigned int dest, int dest_mode);
+int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2);
+void kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu, int vector,
+			int trigger_mode);
+bool kvm_ioapic_handles_vector(struct kvm *kvm, int vector);
+int kvm_ioapic_init(struct kvm *kvm);
+void kvm_ioapic_destroy(struct kvm *kvm);
+int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
+		       int level, bool line_status);
+void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id);
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+		struct kvm_lapic_irq *irq, unsigned long *dest_map);
+int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
+int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
+			u32 *tmr);
+
+#endif
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
new file mode 100644
index 000000000000..e9c135b639aa
--- /dev/null
+++ b/arch/x86/kvm/irq_comm.c
@@ -0,0 +1,347 @@
+/*
+ * 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>
+ *
+ * Copyright 2010 Red Hat, Inc. and/or its affiliates.
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <trace/events/kvm.h>
+
+#include <asm/msidef.h>
+
+#include "irq.h"
+
+#include "ioapic.h"
+
+static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
+			   struct kvm *kvm, int irq_source_id, int level,
+			   bool line_status)
+{
+#ifdef CONFIG_X86
+	struct kvm_pic *pic = pic_irqchip(kvm);
+	return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
+#else
+	return -1;
+#endif
+}
+
+static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
+			      struct kvm *kvm, int irq_source_id, int level,
+			      bool line_status)
+{
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+	return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level,
+				line_status);
+}
+
+inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
+{
+	return irq->delivery_mode == APIC_DM_LOWEST;
+}
+
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+		struct kvm_lapic_irq *irq, unsigned long *dest_map)
+{
+	int i, r = -1;
+	struct kvm_vcpu *vcpu, *lowest = NULL;
+
+	if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
+			kvm_is_dm_lowest_prio(irq)) {
+		printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
+		irq->delivery_mode = APIC_DM_FIXED;
+	}
+
+	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
+		return r;
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		if (!kvm_apic_present(vcpu))
+			continue;
+
+		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
+					irq->dest_id, irq->dest_mode))
+			continue;
+
+		if (!kvm_is_dm_lowest_prio(irq)) {
+			if (r < 0)
+				r = 0;
+			r += kvm_apic_set_irq(vcpu, irq, dest_map);
+		} else if (kvm_lapic_enabled(vcpu)) {
+			if (!lowest)
+				lowest = vcpu;
+			else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
+				lowest = vcpu;
+		}
+	}
+
+	if (lowest)
+		r = kvm_apic_set_irq(lowest, irq, dest_map);
+
+	return r;
+}
+
+static inline void kvm_set_msi_irq(struct kvm_kernel_irq_routing_entry *e,
+				   struct kvm_lapic_irq *irq)
+{
+	trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
+
+	irq->dest_id = (e->msi.address_lo &
+			MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
+	irq->vector = (e->msi.data &
+			MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
+	irq->dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
+	irq->trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
+	irq->delivery_mode = e->msi.data & 0x700;
+	irq->level = 1;
+	irq->shorthand = 0;
+	/* TODO Deal with RH bit of MSI message address */
+}
+
+int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
+		struct kvm *kvm, int irq_source_id, int level, bool line_status)
+{
+	struct kvm_lapic_irq irq;
+
+	if (!level)
+		return -1;
+
+	kvm_set_msi_irq(e, &irq);
+
+	return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
+}
+
+
+static int kvm_set_msi_inatomic(struct kvm_kernel_irq_routing_entry *e,
+			 struct kvm *kvm)
+{
+	struct kvm_lapic_irq irq;
+	int r;
+
+	kvm_set_msi_irq(e, &irq);
+
+	if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
+		return r;
+	else
+		return -EWOULDBLOCK;
+}
+
+/*
+ * Deliver an IRQ in an atomic context if we can, or return a failure,
+ * user can retry in a process context.
+ * Return value:
+ *  -EWOULDBLOCK - Can't deliver in atomic context: retry in a process context.
+ *  Other values - No need to retry.
+ */
+int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level)
+{
+	struct kvm_kernel_irq_routing_entry entries[KVM_NR_IRQCHIPS];
+	struct kvm_kernel_irq_routing_entry *e;
+	int ret = -EINVAL;
+	int idx;
+
+	trace_kvm_set_irq(irq, level, irq_source_id);
+
+	/*
+	 * Injection into either PIC or IOAPIC might need to scan all CPUs,
+	 * which would need to be retried from thread context;  when same GSI
+	 * is connected to both PIC and IOAPIC, we'd have to report a
+	 * partial failure here.
+	 * Since there's no easy way to do this, we only support injecting MSI
+	 * which is limited to 1:1 GSI mapping.
+	 */
+	idx = srcu_read_lock(&kvm->irq_srcu);
+	if (kvm_irq_map_gsi(kvm, entries, irq) > 0) {
+		e = &entries[0];
+		if (likely(e->type == KVM_IRQ_ROUTING_MSI))
+			ret = kvm_set_msi_inatomic(e, kvm);
+		else
+			ret = -EWOULDBLOCK;
+	}
+	srcu_read_unlock(&kvm->irq_srcu, idx);
+	return ret;
+}
+
+int kvm_request_irq_source_id(struct kvm *kvm)
+{
+	unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
+	int irq_source_id;
+
+	mutex_lock(&kvm->irq_lock);
+	irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
+
+	if (irq_source_id >= BITS_PER_LONG) {
+		printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
+		irq_source_id = -EFAULT;
+		goto unlock;
+	}
+
+	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
+#ifdef CONFIG_X86
+	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
+#endif
+	set_bit(irq_source_id, bitmap);
+unlock:
+	mutex_unlock(&kvm->irq_lock);
+
+	return irq_source_id;
+}
+
+void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
+{
+	ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
+#ifdef CONFIG_X86
+	ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
+#endif
+
+	mutex_lock(&kvm->irq_lock);
+	if (irq_source_id < 0 ||
+	    irq_source_id >= BITS_PER_LONG) {
+		printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
+		goto unlock;
+	}
+	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
+	if (!irqchip_in_kernel(kvm))
+		goto unlock;
+
+	kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
+#ifdef CONFIG_X86
+	kvm_pic_clear_all(pic_irqchip(kvm), irq_source_id);
+#endif
+unlock:
+	mutex_unlock(&kvm->irq_lock);
+}
+
+void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
+				    struct kvm_irq_mask_notifier *kimn)
+{
+	mutex_lock(&kvm->irq_lock);
+	kimn->irq = irq;
+	hlist_add_head_rcu(&kimn->link, &kvm->arch.mask_notifier_list);
+	mutex_unlock(&kvm->irq_lock);
+}
+
+void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
+				      struct kvm_irq_mask_notifier *kimn)
+{
+	mutex_lock(&kvm->irq_lock);
+	hlist_del_rcu(&kimn->link);
+	mutex_unlock(&kvm->irq_lock);
+	synchronize_srcu(&kvm->irq_srcu);
+}
+
+void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
+			     bool mask)
+{
+	struct kvm_irq_mask_notifier *kimn;
+	int idx, gsi;
+
+	idx = srcu_read_lock(&kvm->irq_srcu);
+	gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin);
+	if (gsi != -1)
+		hlist_for_each_entry_rcu(kimn, &kvm->arch.mask_notifier_list, link)
+			if (kimn->irq == gsi)
+				kimn->func(kimn, mask);
+	srcu_read_unlock(&kvm->irq_srcu, idx);
+}
+
+int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e,
+			  const struct kvm_irq_routing_entry *ue)
+{
+	int r = -EINVAL;
+	int delta;
+	unsigned max_pin;
+
+	switch (ue->type) {
+	case KVM_IRQ_ROUTING_IRQCHIP:
+		delta = 0;
+		switch (ue->u.irqchip.irqchip) {
+		case KVM_IRQCHIP_PIC_MASTER:
+			e->set = kvm_set_pic_irq;
+			max_pin = PIC_NUM_PINS;
+			break;
+		case KVM_IRQCHIP_PIC_SLAVE:
+			e->set = kvm_set_pic_irq;
+			max_pin = PIC_NUM_PINS;
+			delta = 8;
+			break;
+		case KVM_IRQCHIP_IOAPIC:
+			max_pin = KVM_IOAPIC_NUM_PINS;
+			e->set = kvm_set_ioapic_irq;
+			break;
+		default:
+			goto out;
+		}
+		e->irqchip.irqchip = ue->u.irqchip.irqchip;
+		e->irqchip.pin = ue->u.irqchip.pin + delta;
+		if (e->irqchip.pin >= max_pin)
+			goto out;
+		break;
+	case KVM_IRQ_ROUTING_MSI:
+		e->set = kvm_set_msi;
+		e->msi.address_lo = ue->u.msi.address_lo;
+		e->msi.address_hi = ue->u.msi.address_hi;
+		e->msi.data = ue->u.msi.data;
+		break;
+	default:
+		goto out;
+	}
+
+	r = 0;
+out:
+	return r;
+}
+
+#define IOAPIC_ROUTING_ENTRY(irq) \
+	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
+	  .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
+#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
+
+#ifdef CONFIG_X86
+#  define PIC_ROUTING_ENTRY(irq) \
+	{ .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,	\
+	  .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } }
+#  define ROUTING_ENTRY2(irq) \
+	IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
+#else
+#  define ROUTING_ENTRY2(irq) \
+	IOAPIC_ROUTING_ENTRY(irq)
+#endif
+
+static const struct kvm_irq_routing_entry default_routing[] = {
+	ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
+	ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
+	ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
+	ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
+	ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
+	ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
+	ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
+	ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
+	ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
+	ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
+	ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
+	ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
+};
+
+int kvm_setup_default_irq_routing(struct kvm *kvm)
+{
+	return kvm_set_irq_routing(kvm, default_routing,
+				   ARRAY_SIZE(default_routing), 0);
+}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a8f53a6960fd..5337039427c8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7264,6 +7264,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	if (type)
 		return -EINVAL;
 
+	INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list);
 	INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
 	INIT_LIST_HEAD(&kvm->arch.zapped_obsolete_pages);
 	INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);