summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--virt/kvm/coalesced_mmio.c10
1 files changed, 5 insertions, 5 deletions
diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index c4c7ec2f9d30..754906800999 100644
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -24,7 +24,8 @@ static int coalesced_mmio_in_range(struct kvm_io_device *this,
{
struct kvm_coalesced_mmio_dev *dev = to_mmio(this);
struct kvm_coalesced_mmio_zone *zone;
- int next;
+ struct kvm_coalesced_mmio_ring *ring;
+ unsigned avail;
int i;
if (!is_write)
@@ -40,10 +41,9 @@ static int coalesced_mmio_in_range(struct kvm_io_device *this,
* check if we don't meet the first used entry
* there is always one unused entry in the buffer
*/
-
- next = (dev->kvm->coalesced_mmio_ring->last + 1) %
- KVM_COALESCED_MMIO_MAX;
- if (next == dev->kvm->coalesced_mmio_ring->first) {
+ ring = dev->kvm->coalesced_mmio_ring;
+ avail = (ring->first - ring->last - 1) % KVM_COALESCED_MMIO_MAX;
+ if (avail < 1) {
/* full */
return 0;
}