hv_sock: disable SO_RCVLOWAT support

For Hyper-V it is quiet difficult to support this socket option,due to
transport internals, so disable it.

Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
index fd98229..59c3e26 100644 (file)
--- a/net/vmw_vsock/hyperv_transport.c
+++ b/net/vmw_vsock/hyperv_transport.c
@@ -815,6 +815,12 @@ int hvs_notify_send_post_enqueue(struct vsock_sock *vsk, ssize_t written,
        return 0;
 }
 
+static
+int hvs_set_rcvlowat(struct vsock_sock *vsk, int val)
+{
+       return -EOPNOTSUPP;
+}
+
 static struct vsock_transport hvs_transport = {
        .module                   = THIS_MODULE,
 
@@ -850,6 +856,7 @@ static struct vsock_transport hvs_transport = {
        .notify_send_pre_enqueue  = hvs_notify_send_pre_enqueue,
        .notify_send_post_enqueue = hvs_notify_send_post_enqueue,
 
+       .set_rcvlowat             = hvs_set_rcvlowat
 };
 
 static bool hvs_check_transport(struct vsock_sock *vsk)