[RFC PATCH v5 11/17] vsock/virtio: support MSG_ZEROCOPY for transport

[Arseniy Krasnov <AVKrasnov@sberdevices.ru>]

Add 'msgzerocopy_allow()' callback for virtio transport.

Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
---
 Changelog:
 v4 -> v5:
  * Move 'msgzerocopy_allow' right after seqpacket callbacks.

 net/vmw_vsock/virtio_transport.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 6cbb45bb12d2..8d3e9f441fa1 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -441,6 +441,11 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
 	queue_work(virtio_vsock_workqueue, &vsock->rx_work);
 }
 
+static bool virtio_transport_msgzerocopy_allow(void)
+{
+	return true;
+}
+
 static bool virtio_transport_seqpacket_allow(u32 remote_cid);
 
 static struct virtio_transport virtio_transport = {
@@ -474,6 +479,8 @@ static struct virtio_transport virtio_transport = {
 		.seqpacket_allow          = virtio_transport_seqpacket_allow,
 		.seqpacket_has_data       = virtio_transport_seqpacket_has_data,
 
+		.msgzerocopy_allow        = virtio_transport_msgzerocopy_allow,
+
 		.notify_poll_in           = virtio_transport_notify_poll_in,
 		.notify_poll_out          = virtio_transport_notify_poll_out,
 		.notify_recv_init         = virtio_transport_notify_recv_init,
-- 
2.25.1