Signed-off-by: Eugenio Pérez <epere...@redhat.com> --- hw/virtio/vhost-shadow-virtqueue.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-)
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index 7df98fc43f..e3879a4622 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -71,10 +71,35 @@ typedef struct VhostShadowVirtqueue { /* Next head to consume from device */ uint16_t used_idx; + /* Cache for the exposed notification flag */ + bool notification; + /* Descriptors copied from guest */ vring_desc_t descs[]; } VhostShadowVirtqueue; +static void vhost_shadow_vq_set_notification(VhostShadowVirtqueue *svq, + bool enable) +{ + uint16_t notification_flag; + + if (svq->notification == enable) { + return; + } + + notification_flag = virtio_tswap16(svq->vdev, VRING_AVAIL_F_NO_INTERRUPT); + + svq->notification = enable; + if (enable) { + svq->vring.avail->flags &= ~notification_flag; + } else { + svq->vring.avail->flags |= notification_flag; + } + + /* Make sure device reads our flag */ + smp_mb(); +} + static void vhost_vring_write_descs(VhostShadowVirtqueue *svq, const struct iovec *iovec, size_t num, bool more_descs, bool write) @@ -251,7 +276,7 @@ static void vhost_shadow_vq_handle_call_no_test(EventNotifier *n) do { unsigned i = 0; - /* TODO: Use VRING_AVAIL_F_NO_INTERRUPT */ + vhost_shadow_vq_set_notification(svq, false); while (true) { g_autofree VirtQueueElement *elem = vhost_shadow_vq_get_buf(svq); if (!elem) { @@ -269,6 +294,7 @@ static void vhost_shadow_vq_handle_call_no_test(EventNotifier *n) svq->masked_notifier.signaled = true; event_notifier_set(svq->masked_notifier.n); } + vhost_shadow_vq_set_notification(svq, true); } while (vhost_shadow_vq_more_used(svq)); if (masked_notifier) { -- 2.27.0