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authorLinus Torvalds <torvalds@linux-foundation.org>2011-10-30 15:36:45 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-10-30 15:36:45 -0700
commit1bc87b00556e8f7ba30a1010471951c5b8f71114 (patch)
treee73c2d187e2dff0df97ed82e32b45e362b923117 /virt
parentacff987d94cbdb4049f3706bed1f1792f8ef6837 (diff)
parentf1c1da2bde712812a3e0f9a7a7ebe7a916a4b5f4 (diff)
downloadlinux-1bc87b00556e8f7ba30a1010471951c5b8f71114.tar.gz
Merge branch 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (75 commits)
  KVM: SVM: Keep intercepting task switching with NPT enabled
  KVM: s390: implement sigp external call
  KVM: s390: fix register setting
  KVM: s390: fix return value of kvm_arch_init_vm
  KVM: s390: check cpu_id prior to using it
  KVM: emulate lapic tsc deadline timer for guest
  x86: TSC deadline definitions
  KVM: Fix simultaneous NMIs
  KVM: x86 emulator: convert push %sreg/pop %sreg to direct decode
  KVM: x86 emulator: switch lds/les/lss/lfs/lgs to direct decode
  KVM: x86 emulator: streamline decode of segment registers
  KVM: x86 emulator: simplify OpMem64 decode
  KVM: x86 emulator: switch src decode to decode_operand()
  KVM: x86 emulator: qualify OpReg inhibit_byte_regs hack
  KVM: x86 emulator: switch OpImmUByte decode to decode_imm()
  KVM: x86 emulator: free up some flag bits near src, dst
  KVM: x86 emulator: switch src2 to generic decode_operand()
  KVM: x86 emulator: expand decode flags to 64 bits
  KVM: x86 emulator: split dst decode to a generic decode_operand()
  KVM: x86 emulator: move memop, memopp into emulation context
  ...
Diffstat (limited to 'virt')
-rw-r--r--virt/kvm/assigned-dev.c62
-rw-r--r--virt/kvm/coalesced_mmio.c131
-rw-r--r--virt/kvm/coalesced_mmio.h7
-rw-r--r--virt/kvm/eventfd.c3
-rw-r--r--virt/kvm/ioapic.c3
-rw-r--r--virt/kvm/kvm_main.c112
6 files changed, 200 insertions, 118 deletions
diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c
index eaf3a50f9769..3ad0925d23a9 100644
--- a/virt/kvm/assigned-dev.c
+++ b/virt/kvm/assigned-dev.c
@@ -58,8 +58,6 @@ static int find_index_from_host_irq(struct kvm_assigned_dev_kernel
 static irqreturn_t kvm_assigned_dev_thread(int irq, void *dev_id)
 {
 	struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
-	u32 vector;
-	int index;
 
 	if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_INTX) {
 		spin_lock(&assigned_dev->intx_lock);
@@ -68,31 +66,35 @@ static irqreturn_t kvm_assigned_dev_thread(int irq, void *dev_id)
 		spin_unlock(&assigned_dev->intx_lock);
 	}
 
-	if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
-		index = find_index_from_host_irq(assigned_dev, irq);
-		if (index >= 0) {
-			vector = assigned_dev->
-					guest_msix_entries[index].vector;
-			kvm_set_irq(assigned_dev->kvm,
-				    assigned_dev->irq_source_id, vector, 1);
-		}
-	} else
+	kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
+		    assigned_dev->guest_irq, 1);
+
+	return IRQ_HANDLED;
+}
+
+#ifdef __KVM_HAVE_MSIX
+static irqreturn_t kvm_assigned_dev_thread_msix(int irq, void *dev_id)
+{
+	struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+	int index = find_index_from_host_irq(assigned_dev, irq);
+	u32 vector;
+
+	if (index >= 0) {
+		vector = assigned_dev->guest_msix_entries[index].vector;
 		kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
-			    assigned_dev->guest_irq, 1);
+			    vector, 1);
+	}
 
 	return IRQ_HANDLED;
 }
+#endif
 
 /* Ack the irq line for an assigned device */
 static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
 {
-	struct kvm_assigned_dev_kernel *dev;
-
-	if (kian->gsi == -1)
-		return;
-
-	dev = container_of(kian, struct kvm_assigned_dev_kernel,
-			   ack_notifier);
+	struct kvm_assigned_dev_kernel *dev =
+		container_of(kian, struct kvm_assigned_dev_kernel,
+			     ack_notifier);
 
 	kvm_set_irq(dev->kvm, dev->irq_source_id, dev->guest_irq, 0);
 
@@ -110,8 +112,9 @@ static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
 static void deassign_guest_irq(struct kvm *kvm,
 			       struct kvm_assigned_dev_kernel *assigned_dev)
 {
-	kvm_unregister_irq_ack_notifier(kvm, &assigned_dev->ack_notifier);
-	assigned_dev->ack_notifier.gsi = -1;
+	if (assigned_dev->ack_notifier.gsi != -1)
+		kvm_unregister_irq_ack_notifier(kvm,
+						&assigned_dev->ack_notifier);
 
 	kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
 		    assigned_dev->guest_irq, 0);
@@ -143,7 +146,7 @@ static void deassign_host_irq(struct kvm *kvm,
 
 		for (i = 0; i < assigned_dev->entries_nr; i++)
 			free_irq(assigned_dev->host_msix_entries[i].vector,
-				 (void *)assigned_dev);
+				 assigned_dev);
 
 		assigned_dev->entries_nr = 0;
 		kfree(assigned_dev->host_msix_entries);
@@ -153,7 +156,7 @@ static void deassign_host_irq(struct kvm *kvm,
 		/* Deal with MSI and INTx */
 		disable_irq(assigned_dev->host_irq);
 
-		free_irq(assigned_dev->host_irq, (void *)assigned_dev);
+		free_irq(assigned_dev->host_irq, assigned_dev);
 
 		if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSI)
 			pci_disable_msi(assigned_dev->dev);
@@ -239,7 +242,7 @@ static int assigned_device_enable_host_intx(struct kvm *kvm,
 	 * are going to be long delays in accepting, acking, etc.
 	 */
 	if (request_threaded_irq(dev->host_irq, NULL, kvm_assigned_dev_thread,
-				 IRQF_ONESHOT, dev->irq_name, (void *)dev))
+				 IRQF_ONESHOT, dev->irq_name, dev))
 		return -EIO;
 	return 0;
 }
@@ -258,7 +261,7 @@ static int assigned_device_enable_host_msi(struct kvm *kvm,
 
 	dev->host_irq = dev->dev->irq;
 	if (request_threaded_irq(dev->host_irq, NULL, kvm_assigned_dev_thread,
-				 0, dev->irq_name, (void *)dev)) {
+				 0, dev->irq_name, dev)) {
 		pci_disable_msi(dev->dev);
 		return -EIO;
 	}
@@ -284,8 +287,8 @@ static int assigned_device_enable_host_msix(struct kvm *kvm,
 
 	for (i = 0; i < dev->entries_nr; i++) {
 		r = request_threaded_irq(dev->host_msix_entries[i].vector,
-					 NULL, kvm_assigned_dev_thread,
-					 0, dev->irq_name, (void *)dev);
+					 NULL, kvm_assigned_dev_thread_msix,
+					 0, dev->irq_name, dev);
 		if (r)
 			goto err;
 	}
@@ -293,7 +296,7 @@ static int assigned_device_enable_host_msix(struct kvm *kvm,
 	return 0;
 err:
 	for (i -= 1; i >= 0; i--)
-		free_irq(dev->host_msix_entries[i].vector, (void *)dev);
+		free_irq(dev->host_msix_entries[i].vector, dev);
 	pci_disable_msix(dev->dev);
 	return r;
 }
@@ -406,7 +409,8 @@ static int assign_guest_irq(struct kvm *kvm,
 
 	if (!r) {
 		dev->irq_requested_type |= guest_irq_type;
-		kvm_register_irq_ack_notifier(kvm, &dev->ack_notifier);
+		if (dev->ack_notifier.gsi != -1)
+			kvm_register_irq_ack_notifier(kvm, &dev->ack_notifier);
 	} else
 		kvm_free_irq_source_id(kvm, dev->irq_source_id);
 
diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index fc8487564d1f..a6ec206f36ba 100644
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -24,10 +24,19 @@ static inline struct kvm_coalesced_mmio_dev *to_mmio(struct kvm_io_device *dev)
 static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev,
 				   gpa_t addr, int len)
 {
-	struct kvm_coalesced_mmio_zone *zone;
+	/* is it in a batchable area ?
+	 * (addr,len) is fully included in
+	 * (zone->addr, zone->size)
+	 */
+
+	return (dev->zone.addr <= addr &&
+		addr + len <= dev->zone.addr + dev->zone.size);
+}
+
+static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_dev *dev)
+{
 	struct kvm_coalesced_mmio_ring *ring;
 	unsigned avail;
-	int i;
 
 	/* Are we able to batch it ? */
 
@@ -37,25 +46,12 @@ static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev,
 	 */
 	ring = dev->kvm->coalesced_mmio_ring;
 	avail = (ring->first - ring->last - 1) % KVM_COALESCED_MMIO_MAX;
-	if (avail < KVM_MAX_VCPUS) {
+	if (avail == 0) {
 		/* full */
 		return 0;
 	}
 
-	/* is it in a batchable area ? */
-
-	for (i = 0; i < dev->nb_zones; i++) {
-		zone = &dev->zone[i];
-
-		/* (addr,len) is fully included in
-		 * (zone->addr, zone->size)
-		 */
-
-		if (zone->addr <= addr &&
-		    addr + len <= zone->addr + zone->size)
-			return 1;
-	}
-	return 0;
+	return 1;
 }
 
 static int coalesced_mmio_write(struct kvm_io_device *this,
@@ -63,10 +59,16 @@ static int coalesced_mmio_write(struct kvm_io_device *this,
 {
 	struct kvm_coalesced_mmio_dev *dev = to_mmio(this);
 	struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring;
+
 	if (!coalesced_mmio_in_range(dev, addr, len))
 		return -EOPNOTSUPP;
 
-	spin_lock(&dev->lock);
+	spin_lock(&dev->kvm->ring_lock);
+
+	if (!coalesced_mmio_has_room(dev)) {
+		spin_unlock(&dev->kvm->ring_lock);
+		return -EOPNOTSUPP;
+	}
 
 	/* copy data in first free entry of the ring */
 
@@ -75,7 +77,7 @@ static int coalesced_mmio_write(struct kvm_io_device *this,
 	memcpy(ring->coalesced_mmio[ring->last].data, val, len);
 	smp_wmb();
 	ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX;
-	spin_unlock(&dev->lock);
+	spin_unlock(&dev->kvm->ring_lock);
 	return 0;
 }
 
@@ -83,6 +85,8 @@ static void coalesced_mmio_destructor(struct kvm_io_device *this)
 {
 	struct kvm_coalesced_mmio_dev *dev = to_mmio(this);
 
+	list_del(&dev->list);
+
 	kfree(dev);
 }
 
@@ -93,7 +97,6 @@ static const struct kvm_io_device_ops coalesced_mmio_ops = {
 
 int kvm_coalesced_mmio_init(struct kvm *kvm)
 {
-	struct kvm_coalesced_mmio_dev *dev;
 	struct page *page;
 	int ret;
 
@@ -101,31 +104,18 @@ int kvm_coalesced_mmio_init(struct kvm *kvm)
 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
 	if (!page)
 		goto out_err;
-	kvm->coalesced_mmio_ring = page_address(page);
-
-	ret = -ENOMEM;
-	dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL);
-	if (!dev)
-		goto out_free_page;
-	spin_lock_init(&dev->lock);
-	kvm_iodevice_init(&dev->dev, &coalesced_mmio_ops);
-	dev->kvm = kvm;
-	kvm->coalesced_mmio_dev = dev;
 
-	mutex_lock(&kvm->slots_lock);
-	ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &dev->dev);
-	mutex_unlock(&kvm->slots_lock);
-	if (ret < 0)
-		goto out_free_dev;
+	ret = 0;
+	kvm->coalesced_mmio_ring = page_address(page);
 
-	return ret;
+	/*
+	 * We're using this spinlock to sync access to the coalesced ring.
+	 * The list doesn't need it's own lock since device registration and
+	 * unregistration should only happen when kvm->slots_lock is held.
+	 */
+	spin_lock_init(&kvm->ring_lock);
+	INIT_LIST_HEAD(&kvm->coalesced_zones);
 
-out_free_dev:
-	kvm->coalesced_mmio_dev = NULL;
-	kfree(dev);
-out_free_page:
-	kvm->coalesced_mmio_ring = NULL;
-	__free_page(page);
 out_err:
 	return ret;
 }
@@ -139,51 +129,50 @@ void kvm_coalesced_mmio_free(struct kvm *kvm)
 int kvm_vm_ioctl_register_coalesced_mmio(struct kvm *kvm,
 					 struct kvm_coalesced_mmio_zone *zone)
 {
-	struct kvm_coalesced_mmio_dev *dev = kvm->coalesced_mmio_dev;
+	int ret;
+	struct kvm_coalesced_mmio_dev *dev;
 
-	if (dev == NULL)
-		return -ENXIO;
+	dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+
+	kvm_iodevice_init(&dev->dev, &coalesced_mmio_ops);
+	dev->kvm = kvm;
+	dev->zone = *zone;
 
 	mutex_lock(&kvm->slots_lock);
-	if (dev->nb_zones >= KVM_COALESCED_MMIO_ZONE_MAX) {
-		mutex_unlock(&kvm->slots_lock);
-		return -ENOBUFS;
-	}
+	ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, zone->addr,
+				      zone->size, &dev->dev);
+	if (ret < 0)
+		goto out_free_dev;
+	list_add_tail(&dev->list, &kvm->coalesced_zones);
+	mutex_unlock(&kvm->slots_lock);
 
-	dev->zone[dev->nb_zones] = *zone;
-	dev->nb_zones++;
+	return ret;
 
+out_free_dev:
 	mutex_unlock(&kvm->slots_lock);
+
+	kfree(dev);
+
+	if (dev == NULL)
+		return -ENXIO;
+
 	return 0;
 }
 
 int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm,
 					   struct kvm_coalesced_mmio_zone *zone)
 {
-	int i;
-	struct kvm_coalesced_mmio_dev *dev = kvm->coalesced_mmio_dev;
-	struct kvm_coalesced_mmio_zone *z;
-
-	if (dev == NULL)
-		return -ENXIO;
+	struct kvm_coalesced_mmio_dev *dev, *tmp;
 
 	mutex_lock(&kvm->slots_lock);
 
-	i = dev->nb_zones;
-	while (i) {
-		z = &dev->zone[i - 1];
-
-		/* unregister all zones
-		 * included in (zone->addr, zone->size)
-		 */
-
-		if (zone->addr <= z->addr &&
-		    z->addr + z->size <= zone->addr + zone->size) {
-			dev->nb_zones--;
-			*z = dev->zone[dev->nb_zones];
+	list_for_each_entry_safe(dev, tmp, &kvm->coalesced_zones, list)
+		if (coalesced_mmio_in_range(dev, zone->addr, zone->size)) {
+			kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &dev->dev);
+			kvm_iodevice_destructor(&dev->dev);
 		}
-		i--;
-	}
 
 	mutex_unlock(&kvm->slots_lock);
 
diff --git a/virt/kvm/coalesced_mmio.h b/virt/kvm/coalesced_mmio.h
index 8a5959e3535f..b280c20444d1 100644
--- a/virt/kvm/coalesced_mmio.h
+++ b/virt/kvm/coalesced_mmio.h
@@ -12,14 +12,13 @@
 
 #ifdef CONFIG_KVM_MMIO
 
-#define KVM_COALESCED_MMIO_ZONE_MAX 100
+#include <linux/list.h>
 
 struct kvm_coalesced_mmio_dev {
+	struct list_head list;
 	struct kvm_io_device dev;
 	struct kvm *kvm;
-	spinlock_t lock;
-	int nb_zones;
-	struct kvm_coalesced_mmio_zone zone[KVM_COALESCED_MMIO_ZONE_MAX];
+	struct kvm_coalesced_mmio_zone zone;
 };
 
 int kvm_coalesced_mmio_init(struct kvm *kvm);
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 73358d256fa2..f59c1e8de7a2 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -586,7 +586,8 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
 
 	kvm_iodevice_init(&p->dev, &ioeventfd_ops);
 
-	ret = kvm_io_bus_register_dev(kvm, bus_idx, &p->dev);
+	ret = kvm_io_bus_register_dev(kvm, bus_idx, p->addr, p->length,
+				      &p->dev);
 	if (ret < 0)
 		goto unlock_fail;
 
diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 8df1ca104a7f..3eed61eb4867 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -394,7 +394,8 @@ int kvm_ioapic_init(struct kvm *kvm)
 	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->dev);
+	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;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index aefdda390f5e..d9cfb782cb81 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -47,6 +47,8 @@
 #include <linux/srcu.h>
 #include <linux/hugetlb.h>
 #include <linux/slab.h>
+#include <linux/sort.h>
+#include <linux/bsearch.h>
 
 #include <asm/processor.h>
 #include <asm/io.h>
@@ -2391,24 +2393,92 @@ static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
 	int i;
 
 	for (i = 0; i < bus->dev_count; i++) {
-		struct kvm_io_device *pos = bus->devs[i];
+		struct kvm_io_device *pos = bus->range[i].dev;
 
 		kvm_iodevice_destructor(pos);
 	}
 	kfree(bus);
 }
 
+int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
+{
+	const struct kvm_io_range *r1 = p1;
+	const struct kvm_io_range *r2 = p2;
+
+	if (r1->addr < r2->addr)
+		return -1;
+	if (r1->addr + r1->len > r2->addr + r2->len)
+		return 1;
+	return 0;
+}
+
+int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
+			  gpa_t addr, int len)
+{
+	if (bus->dev_count == NR_IOBUS_DEVS)
+		return -ENOSPC;
+
+	bus->range[bus->dev_count++] = (struct kvm_io_range) {
+		.addr = addr,
+		.len = len,
+		.dev = dev,
+	};
+
+	sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
+		kvm_io_bus_sort_cmp, NULL);
+
+	return 0;
+}
+
+int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
+			     gpa_t addr, int len)
+{
+	struct kvm_io_range *range, key;
+	int off;
+
+	key = (struct kvm_io_range) {
+		.addr = addr,
+		.len = len,
+	};
+
+	range = bsearch(&key, bus->range, bus->dev_count,
+			sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
+	if (range == NULL)
+		return -ENOENT;
+
+	off = range - bus->range;
+
+	while (off > 0 && kvm_io_bus_sort_cmp(&key, &bus->range[off-1]) == 0)
+		off--;
+
+	return off;
+}
+
 /* kvm_io_bus_write - called under kvm->slots_lock */
 int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
 		     int len, const void *val)
 {
-	int i;
+	int idx;
 	struct kvm_io_bus *bus;
+	struct kvm_io_range range;
+
+	range = (struct kvm_io_range) {
+		.addr = addr,
+		.len = len,
+	};
 
 	bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
-	for (i = 0; i < bus->dev_count; i++)
-		if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
+	idx = kvm_io_bus_get_first_dev(bus, addr, len);
+	if (idx < 0)
+		return -EOPNOTSUPP;
+
+	while (idx < bus->dev_count &&
+		kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
+		if (!kvm_iodevice_write(bus->range[idx].dev, addr, len, val))
 			return 0;
+		idx++;
+	}
+
 	return -EOPNOTSUPP;
 }
 
@@ -2416,19 +2486,33 @@ int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
 int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
 		    int len, void *val)
 {
-	int i;
+	int idx;
 	struct kvm_io_bus *bus;
+	struct kvm_io_range range;
+
+	range = (struct kvm_io_range) {
+		.addr = addr,
+		.len = len,
+	};
 
 	bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
-	for (i = 0; i < bus->dev_count; i++)
-		if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
+	idx = kvm_io_bus_get_first_dev(bus, addr, len);
+	if (idx < 0)
+		return -EOPNOTSUPP;
+
+	while (idx < bus->dev_count &&
+		kvm_io_bus_sort_cmp(&range, &bus->range[idx]) == 0) {
+		if (!kvm_iodevice_read(bus->range[idx].dev, addr, len, val))
 			return 0;
+		idx++;
+	}
+
 	return -EOPNOTSUPP;
 }
 
 /* Caller must hold slots_lock. */
-int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
-			    struct kvm_io_device *dev)
+int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
+			    int len, struct kvm_io_device *dev)
 {
 	struct kvm_io_bus *new_bus, *bus;
 
@@ -2440,7 +2524,7 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx,
 	if (!new_bus)
 		return -ENOMEM;
 	memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
-	new_bus->devs[new_bus->dev_count++] = dev;
+	kvm_io_bus_insert_dev(new_bus, dev, addr, len);
 	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
 	synchronize_srcu_expedited(&kvm->srcu);
 	kfree(bus);
@@ -2464,9 +2548,13 @@ int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
 
 	r = -ENOENT;
 	for (i = 0; i < new_bus->dev_count; i++)
-		if (new_bus->devs[i] == dev) {
+		if (new_bus->range[i].dev == dev) {
 			r = 0;
-			new_bus->devs[i] = new_bus->devs[--new_bus->dev_count];
+			new_bus->dev_count--;
+			new_bus->range[i] = new_bus->range[new_bus->dev_count];
+			sort(new_bus->range, new_bus->dev_count,
+			     sizeof(struct kvm_io_range),
+			     kvm_io_bus_sort_cmp, NULL);
 			break;
 		}