KVM: move coalesced_mmio locking to its own device

[mv-sheeva.git] / virt / kvm / coalesced_mmio.c

diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index 7549068009994ea1c64d2e7aa98f11b7265e9f98..397f419366987ce86059af806258f41132870a77 100644 (file)
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -31,10 +31,6 @@ static int coalesced_mmio_in_range(struct kvm_io_device *this,
        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
@@ -43,7 +39,7 @@ static int coalesced_mmio_in_range(struct kvm_io_device *this,
         */
        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;
        }
@@ -70,7 +66,7 @@ static void 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;
 
-       /* 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 */
 
@@ -79,6 +75,7 @@ static void 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);
 }
 
 static void coalesced_mmio_destructor(struct kvm_io_device *this)
@@ -101,6 +98,7 @@ int kvm_coalesced_mmio_init(struct kvm *kvm)
        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;