[RFC PATCH v2 5/8] vhost/vsock: enable zerocopy callback

[Arseniy Krasnov <AVKrasnov@sberdevices.ru>]

This adds zerocopy callback to vhost transport.

Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
---
 drivers/vhost/vsock.c | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index 0dc2229f18f7..dcb8182f5ac9 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -481,6 +481,43 @@ static bool vhost_vsock_more_replies(struct vhost_vsock *vsock)
 	return val < vq->num;
 }
 
+static int vhost_transport_zerocopy_set(struct vsock_sock *vsk, bool enable)
+{
+	struct vhost_vsock *vsock;
+
+	rcu_read_lock();
+	vsock = vhost_vsock_get(vsk->remote_addr.svm_cid);
+
+	if (!vsock) {
+		rcu_read_unlock();
+		return -ENODEV;
+	}
+
+	vsock->zerocopy_rx_on = enable;
+	rcu_read_unlock();
+
+	return 0;
+}
+
+static int vhost_transport_zerocopy_get(struct vsock_sock *vsk)
+{
+	struct vhost_vsock *vsock;
+	bool res;
+
+	rcu_read_lock();
+	vsock = vhost_vsock_get(vsk->remote_addr.svm_cid);
+
+	if (!vsock) {
+		rcu_read_unlock();
+		return -ENODEV;
+	}
+
+	res = vsock->zerocopy_rx_on;
+	rcu_read_unlock();
+
+	return res;
+}
+
 static bool vhost_transport_seqpacket_allow(u32 remote_cid);
 
 static struct virtio_transport vhost_transport = {
@@ -508,6 +545,9 @@ static struct virtio_transport vhost_transport = {
 		.stream_rcvhiwat          = virtio_transport_stream_rcvhiwat,
 		.stream_is_active         = virtio_transport_stream_is_active,
 		.stream_allow             = virtio_transport_stream_allow,
+		.zerocopy_dequeue	  = virtio_transport_zerocopy_dequeue,
+		.rx_zerocopy_set	  = vhost_transport_zerocopy_set,
+		.rx_zerocopy_get	  = vhost_transport_zerocopy_get,
 
 		.seqpacket_dequeue        = virtio_transport_seqpacket_dequeue,
 		.seqpacket_enqueue        = virtio_transport_seqpacket_enqueue,
-- 
2.25.1