net: add API to disable/enable polling

When vhost is bound to a backend device, we need to stop polling it when
vhost is started, and restart polling when vhost is stopped.
Add an API for that for use by vhost, and implement in tap backend.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/net/tap.c b/net/tap.c
index 0d8b424123..d3492de116 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -262,6 +262,13 @@ static void tap_cleanup(VLANClientState *nc)
     close(s->fd);
 }
 
+static void tap_poll(VLANClientState *nc, bool enable)
+{
+    TAPState *s = DO_UPCAST(TAPState, nc, nc);
+    tap_read_poll(s, enable);
+    tap_write_poll(s, enable);
+}
+
 /* fd support */
 
 static NetClientInfo net_tap_info = {
@@ -270,6 +277,7 @@ static NetClientInfo net_tap_info = {
     .receive = tap_receive,
     .receive_raw = tap_receive_raw,
     .receive_iov = tap_receive_iov,
+    .poll = tap_poll,
     .cleanup = tap_cleanup,
 };