diff options
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/virtio/vhost-shadow-virtqueue.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index a518f84..f5c0fad 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -369,15 +369,27 @@ static bool vhost_svq_more_used(VhostShadowVirtqueue *svq) */ static bool vhost_svq_enable_notification(VhostShadowVirtqueue *svq) { - svq->vring.avail->flags &= ~cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); - /* Make sure the flag is written before the read of used_idx */ + if (virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) { + uint16_t *used_event = (uint16_t *)&svq->vring.avail->ring[svq->vring.num]; + *used_event = svq->shadow_used_idx; + } else { + svq->vring.avail->flags &= ~cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); + } + + /* Make sure the event is enabled before the read of used_idx */ smp_mb(); return !vhost_svq_more_used(svq); } static void vhost_svq_disable_notification(VhostShadowVirtqueue *svq) { - svq->vring.avail->flags |= cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); + /* + * No need to disable notification in the event idx case, since used event + * index is already an index too far away. + */ + if (!virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) { + svq->vring.avail->flags |= cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT); + } } static uint16_t vhost_svq_last_desc_of_chain(const VhostShadowVirtqueue *svq, |