KVM: move coalesced_mmio locking to its own device

	if (!is_write)

		return 0;

	/* kvm->lock is taken by the caller and must be not released before

         * dev.read/write

         */

	/* Are we able to batch it ? */

	/* last is the first free entry

	 */

	ring = dev->kvm->coalesced_mmio_ring;

	avail = (ring->first - ring->last - 1) % KVM_COALESCED_MMIO_MAX;

	if (avail < 1) {

	if (avail < KVM_MAX_VCPUS) {

		/* full */

		return 0;

	}

	struct kvm_coalesced_mmio_dev *dev = to_mmio(this);

	struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring;

	/* kvm->lock must be taken by caller before call to in_range()*/

	spin_lock(&dev->lock);

	/* copy data in first free entry of the ring */

	memcpy(ring->coalesced_mmio[ring->last].data, val, len);

	smp_wmb();

	ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX;

	spin_unlock(&dev->lock);

}

static void coalesced_mmio_destructor(struct kvm_io_device *this)

	dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL);

	if (!dev)

		return -ENOMEM;

	spin_lock_init(&dev->lock);

	kvm_iodevice_init(&dev->dev, &coalesced_mmio_ops);

	dev->kvm = kvm;

	kvm->coalesced_mmio_dev = dev;

struct kvm_coalesced_mmio_dev {

	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];

};