diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 4714f282a43e..2cb1640a90ad 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -586,8 +586,8 @@ struct kvm_fpu {
 
 4.24 KVM_CREATE_IRQCHIP
 
-Capability: KVM_CAP_IRQCHIP
-Architectures: x86, ia64, ARM, arm64
+Capability: KVM_CAP_IRQCHIP, KVM_CAP_S390_IRQCHIP (s390)
+Architectures: x86, ia64, ARM, arm64, s390
 Type: vm ioctl
 Parameters: none
 Returns: 0 on success, -1 on error
@@ -596,7 +596,10 @@ Creates an interrupt controller model in the kernel.  On x86, creates a virtual
 ioapic, a virtual PIC (two PICs, nested), and sets up future vcpus to have a
 local APIC.  IRQ routing for GSIs 0-15 is set to both PIC and IOAPIC; GSI 16-23
 only go to the IOAPIC.  On ia64, a IOSAPIC is created. On ARM/arm64, a GIC is
-created.
+created. On s390, a dummy irq routing table is created.
+
+Note that on s390 the KVM_CAP_S390_IRQCHIP vm capability needs to be enabled
+before KVM_CREATE_IRQCHIP can be used.
 
 
 4.25 KVM_IRQ_LINE
@@ -932,9 +935,9 @@ documentation when it pops into existence).
 
 4.37 KVM_ENABLE_CAP
 
-Capability: KVM_CAP_ENABLE_CAP
+Capability: KVM_CAP_ENABLE_CAP, KVM_CAP_ENABLE_CAP_VM
 Architectures: ppc, s390
-Type: vcpu ioctl
+Type: vcpu ioctl, vm ioctl (with KVM_CAP_ENABLE_CAP_VM)
 Parameters: struct kvm_enable_cap (in)
 Returns: 0 on success; -1 on error
 
@@ -965,6 +968,8 @@ function properly, this is the place to put them.
        __u8  pad[64];
 };
 
+The vcpu ioctl should be used for vcpu-specific capabilities, the vm ioctl
+for vm-wide capabilities.
 
 4.38 KVM_GET_MP_STATE
 
@@ -1334,7 +1339,7 @@ KVM_ASSIGN_DEV_IRQ. Partial deassignment of host or guest IRQ is allowed.
 4.52 KVM_SET_GSI_ROUTING
 
 Capability: KVM_CAP_IRQ_ROUTING
-Architectures: x86 ia64
+Architectures: x86 ia64 s390
 Type: vm ioctl
 Parameters: struct kvm_irq_routing (in)
 Returns: 0 on success, -1 on error
@@ -1357,6 +1362,7 @@ struct kvm_irq_routing_entry {
 	union {
 		struct kvm_irq_routing_irqchip irqchip;
 		struct kvm_irq_routing_msi msi;
+		struct kvm_irq_routing_s390_adapter adapter;
 		__u32 pad[8];
 	} u;
 };
@@ -1364,6 +1370,7 @@ struct kvm_irq_routing_entry {
 /* gsi routing entry types */
 #define KVM_IRQ_ROUTING_IRQCHIP 1
 #define KVM_IRQ_ROUTING_MSI 2
+#define KVM_IRQ_ROUTING_S390_ADAPTER 3
 
 No flags are specified so far, the corresponding field must be set to zero.
 
@@ -1379,6 +1386,14 @@ struct kvm_irq_routing_msi {
 	__u32 pad;
 };
 
+struct kvm_irq_routing_s390_adapter {
+	__u64 ind_addr;
+	__u64 summary_addr;
+	__u64 ind_offset;
+	__u32 summary_offset;
+	__u32 adapter_id;
+};
+
 
 4.53 KVM_ASSIGN_SET_MSIX_NR
 
diff --git a/Documentation/virtual/kvm/devices/s390_flic.txt b/Documentation/virtual/kvm/devices/s390_flic.txt
index 410fa673e5b6..4ceef53164b0 100644
--- a/Documentation/virtual/kvm/devices/s390_flic.txt
+++ b/Documentation/virtual/kvm/devices/s390_flic.txt
@@ -12,6 +12,7 @@ FLIC provides support to
 - inspect currently pending interrupts (KVM_FLIC_GET_ALL_IRQS)
 - purge all pending floating interrupts (KVM_DEV_FLIC_CLEAR_IRQS)
 - enable/disable for the guest transparent async page faults
+- register and modify adapter interrupt sources (KVM_DEV_FLIC_ADAPTER_*)
 
 Groups:
   KVM_DEV_FLIC_ENQUEUE
@@ -44,3 +45,47 @@ Groups:
     Disables async page faults for the guest and waits until already pending
     async page faults are done. This is necessary to trigger a completion interrupt
     for every init interrupt before migrating the interrupt list.
+
+  KVM_DEV_FLIC_ADAPTER_REGISTER
+    Register an I/O adapter interrupt source. Takes a kvm_s390_io_adapter
+    describing the adapter to register:
+
+struct kvm_s390_io_adapter {
+	__u32 id;
+	__u8 isc;
+	__u8 maskable;
+	__u8 swap;
+	__u8 pad;
+};
+
+   id contains the unique id for the adapter, isc the I/O interruption subclass
+   to use, maskable whether this adapter may be masked (interrupts turned off)
+   and swap whether the indicators need to be byte swapped.
+
+
+  KVM_DEV_FLIC_ADAPTER_MODIFY
+    Modifies attributes of an existing I/O adapter interrupt source. Takes
+    a kvm_s390_io_adapter_req specifiying the adapter and the operation:
+
+struct kvm_s390_io_adapter_req {
+	__u32 id;
+	__u8 type;
+	__u8 mask;
+	__u16 pad0;
+	__u64 addr;
+};
+
+    id specifies the adapter and type the operation. The supported operations
+    are:
+
+    KVM_S390_IO_ADAPTER_MASK
+      mask or unmask the adapter, as specified in mask
+
+    KVM_S390_IO_ADAPTER_MAP
+      perform a gmap translation for the guest address provided in addr,
+      pin a userspace page for the translated address and add it to the
+      list of mappings
+
+    KVM_S390_IO_ADAPTER_UNMAP
+      release a userspace page for the translated address specified in addr
+      from the list of mappings
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 734d302ba389..dd3933754d23 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -19,10 +19,19 @@
 #include <linux/kvm.h>
 #include <asm/debug.h>
 #include <asm/cpu.h>
+#include <asm/isc.h>
 
 #define KVM_MAX_VCPUS 64
 #define KVM_USER_MEM_SLOTS 32
 
+/*
+ * These seem to be used for allocating ->chip in the routing table,
+ * which we don't use. 4096 is an out-of-thin-air value. If we need
+ * to look at ->chip later on, we'll need to revisit this.
+ */
+#define KVM_NR_IRQCHIPS 1
+#define KVM_IRQCHIP_NUM_PINS 4096
+
 struct sca_entry {
 	atomic_t scn;
 	__u32	reserved;
@@ -245,6 +254,27 @@ struct kvm_vm_stat {
 struct kvm_arch_memory_slot {
 };
 
+struct s390_map_info {
+	struct list_head list;
+	__u64 guest_addr;
+	__u64 addr;
+	struct page *page;
+};
+
+struct s390_io_adapter {
+	unsigned int id;
+	int isc;
+	bool maskable;
+	bool masked;
+	bool swap;
+	struct rw_semaphore maps_lock;
+	struct list_head maps;
+	atomic_t nr_maps;
+};
+
+#define MAX_S390_IO_ADAPTERS ((MAX_ISC + 1) * 8)
+#define MAX_S390_ADAPTER_MAPS 256
+
 struct kvm_arch{
 	struct sca_block *sca;
 	debug_info_t *dbf;
@@ -252,6 +282,8 @@ struct kvm_arch{
 	struct kvm_device *flic;
 	struct gmap *gmap;
 	int css_support;
+	int use_irqchip;
+	struct s390_io_adapter *adapters[MAX_S390_IO_ADAPTERS];
 };
 
 #define KVM_HVA_ERR_BAD		(-1UL)
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 2f0ade24f96a..c003c6a73b1e 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -22,6 +22,8 @@
 #define KVM_DEV_FLIC_CLEAR_IRQS		3
 #define KVM_DEV_FLIC_APF_ENABLE		4
 #define KVM_DEV_FLIC_APF_DISABLE_WAIT	5
+#define KVM_DEV_FLIC_ADAPTER_REGISTER	6
+#define KVM_DEV_FLIC_ADAPTER_MODIFY	7
 /*
  * We can have up to 4*64k pending subchannels + 8 adapter interrupts,
  * as well as up  to ASYNC_PF_PER_VCPU*KVM_MAX_VCPUS pfault done interrupts.
@@ -32,6 +34,26 @@
 #define KVM_S390_MAX_FLOAT_IRQS	266250
 #define KVM_S390_FLIC_MAX_BUFFER	0x2000000
 
+struct kvm_s390_io_adapter {
+	__u32 id;
+	__u8 isc;
+	__u8 maskable;
+	__u8 swap;
+	__u8 pad;
+};
+
+#define KVM_S390_IO_ADAPTER_MASK 1
+#define KVM_S390_IO_ADAPTER_MAP 2
+#define KVM_S390_IO_ADAPTER_UNMAP 3
+
+struct kvm_s390_io_adapter_req {
+	__u32 id;
+	__u8 type;
+	__u8 mask;
+	__u16 pad0;
+	__u64 addr;
+};
+
 /* for KVM_GET_REGS and KVM_SET_REGS */
 struct kvm_regs {
 	/* general purpose regs for s390 */
diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
index c8bacbcd2e5b..10d529ac9821 100644
--- a/arch/s390/kvm/Kconfig
+++ b/arch/s390/kvm/Kconfig
@@ -25,6 +25,8 @@ config KVM
 	select HAVE_KVM_EVENTFD
 	select KVM_ASYNC_PF
 	select KVM_ASYNC_PF_SYNC
+	select HAVE_KVM_IRQCHIP
+	select HAVE_KVM_IRQ_ROUTING
 	---help---
 	  Support hosting paravirtualized guest machines using the SIE
 	  virtualization capability on the mainframe. This should work
diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index a47d2c355f68..d3adb37e93a4 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -7,7 +7,7 @@
 # as published by the Free Software Foundation.
 
 KVM := ../../../virt/kvm
-common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o  $(KVM)/async_pf.o
+common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o  $(KVM)/async_pf.o $(KVM)/irqchip.o
 
 ccflags-y := -Ivirt/kvm -Iarch/s390/kvm
 
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 79d2e4fa9f9c..2e2814eceb85 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -1,7 +1,7 @@
 /*
  * handling kvm guest interrupts
  *
- * Copyright IBM Corp. 2008
+ * Copyright IBM Corp. 2008,2014
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License (version 2 only)
@@ -13,6 +13,7 @@
 #include <linux/interrupt.h>
 #include <linux/kvm_host.h>
 #include <linux/hrtimer.h>
+#include <linux/mmu_context.h>
 #include <linux/signal.h>
 #include <linux/slab.h>
 #include <asm/asm-offsets.h>
@@ -1054,6 +1055,171 @@ static int enqueue_floating_irq(struct kvm_device *dev,
 	return r;
 }
 
+static struct s390_io_adapter *get_io_adapter(struct kvm *kvm, unsigned int id)
+{
+	if (id >= MAX_S390_IO_ADAPTERS)
+		return NULL;
+	return kvm->arch.adapters[id];
+}
+
+static int register_io_adapter(struct kvm_device *dev,
+			       struct kvm_device_attr *attr)
+{
+	struct s390_io_adapter *adapter;
+	struct kvm_s390_io_adapter adapter_info;
+
+	if (copy_from_user(&adapter_info,
+			   (void __user *)attr->addr, sizeof(adapter_info)))
+		return -EFAULT;
+
+	if ((adapter_info.id >= MAX_S390_IO_ADAPTERS) ||
+	    (dev->kvm->arch.adapters[adapter_info.id] != NULL))
+		return -EINVAL;
+
+	adapter = kzalloc(sizeof(*adapter), GFP_KERNEL);
+	if (!adapter)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&adapter->maps);
+	init_rwsem(&adapter->maps_lock);
+	atomic_set(&adapter->nr_maps, 0);
+	adapter->id = adapter_info.id;
+	adapter->isc = adapter_info.isc;
+	adapter->maskable = adapter_info.maskable;
+	adapter->masked = false;
+	adapter->swap = adapter_info.swap;
+	dev->kvm->arch.adapters[adapter->id] = adapter;
+
+	return 0;
+}
+
+int kvm_s390_mask_adapter(struct kvm *kvm, unsigned int id, bool masked)
+{
+	int ret;
+	struct s390_io_adapter *adapter = get_io_adapter(kvm, id);
+
+	if (!adapter || !adapter->maskable)
+		return -EINVAL;
+	ret = adapter->masked;
+	adapter->masked = masked;
+	return ret;
+}
+
+static int kvm_s390_adapter_map(struct kvm *kvm, unsigned int id, __u64 addr)
+{
+	struct s390_io_adapter *adapter = get_io_adapter(kvm, id);
+	struct s390_map_info *map;
+	int ret;
+
+	if (!adapter || !addr)
+		return -EINVAL;
+
+	map = kzalloc(sizeof(*map), GFP_KERNEL);
+	if (!map) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	INIT_LIST_HEAD(&map->list);
+	map->guest_addr = addr;
+	map->addr = gmap_translate(addr, kvm->arch.gmap);
+	if (map->addr == -EFAULT) {
+		ret = -EFAULT;
+		goto out;
+	}
+	ret = get_user_pages_fast(map->addr, 1, 1, &map->page);
+	if (ret < 0)
+		goto out;
+	BUG_ON(ret != 1);
+	down_write(&adapter->maps_lock);
+	if (atomic_inc_return(&adapter->nr_maps) < MAX_S390_ADAPTER_MAPS) {
+		list_add_tail(&map->list, &adapter->maps);
+		ret = 0;
+	} else {
+		put_page(map->page);
+		ret = -EINVAL;
+	}
+	up_write(&adapter->maps_lock);
+out:
+	if (ret)
+		kfree(map);
+	return ret;
+}
+
+static int kvm_s390_adapter_unmap(struct kvm *kvm, unsigned int id, __u64 addr)
+{
+	struct s390_io_adapter *adapter = get_io_adapter(kvm, id);
+	struct s390_map_info *map, *tmp;
+	int found = 0;
+
+	if (!adapter || !addr)
+		return -EINVAL;
+
+	down_write(&adapter->maps_lock);
+	list_for_each_entry_safe(map, tmp, &adapter->maps, list) {
+		if (map->guest_addr == addr) {
+			found = 1;
+			atomic_dec(&adapter->nr_maps);
+			list_del(&map->list);
+			put_page(map->page);
+			kfree(map);
+			break;
+		}
+	}
+	up_write(&adapter->maps_lock);
+
+	return found ? 0 : -EINVAL;
+}
+
+void kvm_s390_destroy_adapters(struct kvm *kvm)
+{
+	int i;
+	struct s390_map_info *map, *tmp;
+
+	for (i = 0; i < MAX_S390_IO_ADAPTERS; i++) {
+		if (!kvm->arch.adapters[i])
+			continue;
+		list_for_each_entry_safe(map, tmp,
+					 &kvm->arch.adapters[i]->maps, list) {
+			list_del(&map->list);
+			put_page(map->page);
+			kfree(map);
+		}
+		kfree(kvm->arch.adapters[i]);
+	}
+}
+
+static int modify_io_adapter(struct kvm_device *dev,
+			     struct kvm_device_attr *attr)
+{
+	struct kvm_s390_io_adapter_req req;
+	struct s390_io_adapter *adapter;
+	int ret;
+
+	if (copy_from_user(&req, (void __user *)attr->addr, sizeof(req)))
+		return -EFAULT;
+
+	adapter = get_io_adapter(dev->kvm, req.id);
+	if (!adapter)
+		return -EINVAL;
+	switch (req.type) {
+	case KVM_S390_IO_ADAPTER_MASK:
+		ret = kvm_s390_mask_adapter(dev->kvm, req.id, req.mask);
+		if (ret > 0)
+			ret = 0;
+		break;
+	case KVM_S390_IO_ADAPTER_MAP:
+		ret = kvm_s390_adapter_map(dev->kvm, req.id, req.addr);
+		break;
+	case KVM_S390_IO_ADAPTER_UNMAP:
+		ret = kvm_s390_adapter_unmap(dev->kvm, req.id, req.addr);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
 static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
 {
 	int r = 0;
@@ -1082,6 +1248,12 @@ static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
 		kvm_for_each_vcpu(i, vcpu, dev->kvm)
 			kvm_clear_async_pf_completion_queue(vcpu);
 		break;
+	case KVM_DEV_FLIC_ADAPTER_REGISTER:
+		r = register_io_adapter(dev, attr);
+		break;
+	case KVM_DEV_FLIC_ADAPTER_MODIFY:
+		r = modify_io_adapter(dev, attr);
+		break;
 	default:
 		r = -EINVAL;
 	}
@@ -1113,3 +1285,123 @@ struct kvm_device_ops kvm_flic_ops = {
 	.create = flic_create,
 	.destroy = flic_destroy,
 };
+
+static unsigned long get_ind_bit(__u64 addr, unsigned long bit_nr, bool swap)
+{
+	unsigned long bit;
+
+	bit = bit_nr + (addr % PAGE_SIZE) * 8;
+
+	return swap ? (bit ^ (BITS_PER_LONG - 1)) : bit;
+}
+
+static struct s390_map_info *get_map_info(struct s390_io_adapter *adapter,
+					  u64 addr)
+{
+	struct s390_map_info *map;
+
+	if (!adapter)
+		return NULL;
+
+	list_for_each_entry(map, &adapter->maps, list) {
+		if (map->guest_addr == addr)
+			return map;
+	}
+	return NULL;
+}
+
+static int adapter_indicators_set(struct kvm *kvm,
+				  struct s390_io_adapter *adapter,
+				  struct kvm_s390_adapter_int *adapter_int)
+{
+	unsigned long bit;
+	int summary_set, idx;
+	struct s390_map_info *info;
+	void *map;
+
+	info = get_map_info(adapter, adapter_int->ind_addr);
+	if (!info)
+		return -1;
+	map = page_address(info->page);
+	bit = get_ind_bit(info->addr, adapter_int->ind_offset, adapter->swap);
+	set_bit(bit, map);
+	idx = srcu_read_lock(&kvm->srcu);
+	mark_page_dirty(kvm, info->guest_addr >> PAGE_SHIFT);
+	set_page_dirty_lock(info->page);
+	info = get_map_info(adapter, adapter_int->summary_addr);
+	if (!info) {
+		srcu_read_unlock(&kvm->srcu, idx);
+		return -1;
+	}
+	map = page_address(info->page);
+	bit = get_ind_bit(info->addr, adapter_int->summary_offset,
+			  adapter->swap);
+	summary_set = test_and_set_bit(bit, map);
+	mark_page_dirty(kvm, info->guest_addr >> PAGE_SHIFT);
+	set_page_dirty_lock(info->page);
+	srcu_read_unlock(&kvm->srcu, idx);
+	return summary_set ? 0 : 1;
+}
+
+/*
+ * < 0 - not injected due to error
+ * = 0 - coalesced, summary indicator already active
+ * > 0 - injected interrupt
+ */
+static int set_adapter_int(struct kvm_kernel_irq_routing_entry *e,
+			   struct kvm *kvm, int irq_source_id, int level,
+			   bool line_status)
+{
+	int ret;
+	struct s390_io_adapter *adapter;
+
+	/* We're only interested in the 0->1 transition. */
+	if (!level)
+		return 0;
+	adapter = get_io_adapter(kvm, e->adapter.adapter_id);
+	if (!adapter)
+		return -1;
+	down_read(&adapter->maps_lock);
+	ret = adapter_indicators_set(kvm, adapter, &e->adapter);
+	up_read(&adapter->maps_lock);
+	if ((ret > 0) && !adapter->masked) {
+		struct kvm_s390_interrupt s390int = {
+			.type = KVM_S390_INT_IO(1, 0, 0, 0),
+			.parm = 0,
+			.parm64 = (adapter->isc << 27) | 0x80000000,
+		};
+		ret = kvm_s390_inject_vm(kvm, &s390int);
+		if (ret == 0)
+			ret = 1;
+	}
+	return ret;
+}
+
+int kvm_set_routing_entry(struct kvm_irq_routing_table *rt,
+			  struct kvm_kernel_irq_routing_entry *e,
+			  const struct kvm_irq_routing_entry *ue)
+{
+	int ret;
+
+	switch (ue->type) {
+	case KVM_IRQ_ROUTING_S390_ADAPTER:
+		e->set = set_adapter_int;
+		e->adapter.summary_addr = ue->u.adapter.summary_addr;
+		e->adapter.ind_addr = ue->u.adapter.ind_addr;
+		e->adapter.summary_offset = ue->u.adapter.summary_offset;
+		e->adapter.ind_offset = ue->u.adapter.ind_offset;
+		e->adapter.adapter_id = ue->u.adapter.adapter_id;
+		ret = 0;
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,
+		int irq_source_id, int level, bool line_status)
+{
+	return -EINVAL;
+}
diff --git a/arch/s390/kvm/irq.h b/arch/s390/kvm/irq.h
new file mode 100644
index 000000000000..d98e4159643d
--- /dev/null
+++ b/arch/s390/kvm/irq.h
@@ -0,0 +1,22 @@
+/*
+ * s390 irqchip routines
+ *
+ * Copyright IBM Corp. 2014
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ *    Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
+ */
+#ifndef __KVM_IRQ_H
+#define __KVM_IRQ_H
+
+#include <linux/kvm_host.h>
+
+static inline int irqchip_in_kernel(struct kvm *kvm)
+{
+	return 1;
+}
+
+#endif
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 7337c577e949..ce5b659ec531 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -159,6 +159,7 @@ int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_S390_CSS_SUPPORT:
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_DEVICE_CTRL:
+	case KVM_CAP_ENABLE_CAP_VM:
 		r = 1;
 		break;
 	case KVM_CAP_NR_VCPUS:
@@ -187,6 +188,25 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
 	return 0;
 }
 
+static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
+{
+	int r;
+
+	if (cap->flags)
+		return -EINVAL;
+
+	switch (cap->cap) {
+	case KVM_CAP_S390_IRQCHIP:
+		kvm->arch.use_irqchip = 1;
+		r = 0;
+		break;
+	default:
+		r = -EINVAL;
+		break;
+	}
+	return r;
+}
+
 long kvm_arch_vm_ioctl(struct file *filp,
 		       unsigned int ioctl, unsigned long arg)
 {
@@ -204,6 +224,26 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		r = kvm_s390_inject_vm(kvm, &s390int);
 		break;
 	}
+	case KVM_ENABLE_CAP: {
+		struct kvm_enable_cap cap;
+		r = -EFAULT;
+		if (copy_from_user(&cap, argp, sizeof(cap)))
+			break;
+		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
+		break;
+	}
+	case KVM_CREATE_IRQCHIP: {
+		struct kvm_irq_routing_entry routing;
+
+		r = -EINVAL;
+		if (kvm->arch.use_irqchip) {
+			/* Set up dummy routing. */
+			memset(&routing, 0, sizeof(routing));
+			kvm_set_irq_routing(kvm, &routing, 0, 0);
+			r = 0;
+		}
+		break;
+	}
 	default:
 		r = -ENOTTY;
 	}
@@ -260,6 +300,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	}
 
 	kvm->arch.css_support = 0;
+	kvm->arch.use_irqchip = 0;
 
 	return 0;
 out_nogmap:
@@ -319,6 +360,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 	debug_unregister(kvm->arch.dbf);
 	if (!kvm_is_ucontrol(kvm))
 		gmap_free(kvm->arch.gmap);
+	kvm_s390_destroy_adapters(kvm);
 }
 
 /* Section: vcpu related */
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index ed4750a5bc3c..5502cc951868 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -136,6 +136,7 @@ int __must_check kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
 int __must_check kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code);
 struct kvm_s390_interrupt_info *kvm_s390_get_io_int(struct kvm *kvm,
 						    u64 cr6, u64 schid);
+int kvm_s390_mask_adapter(struct kvm *kvm, unsigned int id, bool masked);
 
 /* implemented in priv.c */
 int kvm_s390_handle_b2(struct kvm_vcpu *vcpu);
@@ -162,5 +163,6 @@ int kvm_s390_handle_diag(struct kvm_vcpu *vcpu);
 /* implemented in interrupt.c */
 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
 int psw_extint_disabled(struct kvm_vcpu *vcpu);
+void kvm_s390_destroy_adapters(struct kvm *kvm);
 
 #endif
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 9816b68b085f..7d21cf9f4380 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -297,6 +297,14 @@ static inline unsigned long kvm_dirty_bitmap_bytes(struct kvm_memory_slot *memsl
 	return ALIGN(memslot->npages, BITS_PER_LONG) / 8;
 }
 
+struct kvm_s390_adapter_int {
+	u64 ind_addr;
+	u64 summary_addr;
+	u64 ind_offset;
+	u32 summary_offset;
+	u32 adapter_id;
+};
+
 struct kvm_kernel_irq_routing_entry {
 	u32 gsi;
 	u32 type;
@@ -309,6 +317,7 @@ struct kvm_kernel_irq_routing_entry {
 			unsigned pin;
 		} irqchip;
 		struct msi_msg msi;
+		struct kvm_s390_adapter_int adapter;
 	};
 	struct hlist_node link;
 };
@@ -913,7 +922,11 @@ static inline int mmu_notifier_retry(struct kvm *kvm, unsigned long mmu_seq)
 
 #ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
 
+#ifdef CONFIG_S390
+#define KVM_MAX_IRQ_ROUTES 4096 //FIXME: we can have more than that...
+#else
 #define KVM_MAX_IRQ_ROUTES 1024
+#endif
 
 int kvm_setup_default_irq_routing(struct kvm *kvm);
 int kvm_set_irq_routing(struct kvm *kvm,
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index a7518be31d53..a8f4ee5d2e82 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -741,6 +741,8 @@ struct kvm_ppc_smmu_info {
 #define KVM_CAP_EXT_EMUL_CPUID 95
 #define KVM_CAP_HYPERV_TIME 96
 #define KVM_CAP_IOAPIC_POLARITY_IGNORED 97
+#define KVM_CAP_ENABLE_CAP_VM 98
+#define KVM_CAP_S390_IRQCHIP 99
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
@@ -756,9 +758,18 @@ struct kvm_irq_routing_msi {
 	__u32 pad;
 };
 
+struct kvm_irq_routing_s390_adapter {
+	__u64 ind_addr;
+	__u64 summary_addr;
+	__u64 ind_offset;
+	__u32 summary_offset;
+	__u32 adapter_id;
+};
+
 /* gsi routing entry types */
 #define KVM_IRQ_ROUTING_IRQCHIP 1
 #define KVM_IRQ_ROUTING_MSI 2
+#define KVM_IRQ_ROUTING_S390_ADAPTER 3
 
 struct kvm_irq_routing_entry {
 	__u32 gsi;
@@ -768,6 +779,7 @@ struct kvm_irq_routing_entry {
 	union {
 		struct kvm_irq_routing_irqchip irqchip;
 		struct kvm_irq_routing_msi msi;
+		struct kvm_irq_routing_s390_adapter adapter;
 		__u32 pad[8];
 	} u;
 };
@@ -1076,6 +1088,10 @@ struct kvm_s390_ucas_mapping {
 /* Available with KVM_CAP_DEBUGREGS */
 #define KVM_GET_DEBUGREGS         _IOR(KVMIO,  0xa1, struct kvm_debugregs)
 #define KVM_SET_DEBUGREGS         _IOW(KVMIO,  0xa2, struct kvm_debugregs)
+/*
+ * vcpu version available with KVM_ENABLE_CAP
+ * vm version available with KVM_CAP_ENABLE_CAP_VM
+ */
 #define KVM_ENABLE_CAP            _IOW(KVMIO,  0xa3, struct kvm_enable_cap)
 /* Available with KVM_CAP_XSAVE */
 #define KVM_GET_XSAVE		  _IOR(KVMIO,  0xa4, struct kvm_xsave)