vsock: add vsock_create_connected() called by transports

All transports call __vsock_create() with the same parameters,
most of them depending on the parent socket. In order to simplify
the VSOCK core APIs exposed to the transports, this patch adds
the vsock_create_connected() callable from transports to create
a new socket when a connection request is received.
We also unexported the __vsock_create().
Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/af_vsock.h

@@ -76,10 +76,7 @@ struct vsock_sock {
 
 s64 vsock_stream_has_data(struct vsock_sock *vsk);
 s64 vsock_stream_has_space(struct vsock_sock *vsk);
-struct sock *__vsock_create(struct net *net,
-			    struct socket *sock,
-			    struct sock *parent,
-			    gfp_t priority, unsigned short type, int kern);
+struct sock *vsock_create_connected(struct sock *parent);
 
 /**** TRANSPORT ****/
 

net/vmw_vsock/af_vsock.c

@@ -567,12 +567,12 @@ static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
 
 static void vsock_connect_timeout(struct work_struct *work);
 
-struct sock *__vsock_create(struct net *net,
-			    struct socket *sock,
-			    struct sock *parent,
-			    gfp_t priority,
-			    unsigned short type,
-			    int kern)
+static struct sock *__vsock_create(struct net *net,
+				   struct socket *sock,
+				   struct sock *parent,
+				   gfp_t priority,
+				   unsigned short type,
+				   int kern)
 {
 	struct sock *sk;
 	struct vsock_sock *psk;
@@ -639,7 +639,6 @@ struct sock *__vsock_create(struct net *net,
 
 	return sk;
 }
-EXPORT_SYMBOL_GPL(__vsock_create);
 
 static void __vsock_release(struct sock *sk, int level)
 {
@@ -703,6 +702,13 @@ static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 	return err;
 }
 
+struct sock *vsock_create_connected(struct sock *parent)
+{
+	return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL,
+			      parent->sk_type, 0);
+}
+EXPORT_SYMBOL_GPL(vsock_create_connected);
+
 s64 vsock_stream_has_data(struct vsock_sock *vsk)
 {
 	return vsk->transport->stream_has_data(vsk);

net/vmw_vsock/hyperv_transport.c

@@ -360,8 +360,7 @@ static void hvs_open_connection(struct vmbus_channel *chan)
 		if (sk->sk_ack_backlog >= sk->sk_max_ack_backlog)
 			goto out;
 
-		new = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
-				     sk->sk_type, 0);
+		new = vsock_create_connected(sk);
 		if (!new)
 			goto out;
 

net/vmw_vsock/virtio_transport_common.c

@@ -1004,8 +1004,7 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt)
 		return -ENOMEM;
 	}
 
-	child = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
-			       sk->sk_type, 0);
+	child = vsock_create_connected(sk);
 	if (!child) {
 		virtio_transport_reset(vsk, pkt);
 		return -ENOMEM;

net/vmw_vsock/vmci_transport.c

@@ -1004,8 +1004,7 @@ static int vmci_transport_recv_listen(struct sock *sk,
 		return -ECONNREFUSED;
 	}
 
-	pending = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
-				 sk->sk_type, 0);
+	pending = vsock_create_connected(sk);
 	if (!pending) {
 		vmci_transport_send_reset(sk, pkt);
 		return -ENOMEM;