vsock: handle buffer_size sockopts in the core

virtio_transport and vmci_transport handle the buffer_size
sockopts in a very similar way.

In order to support multiple transports, this patch moves this
handling in the core to allow the user to change the options
also if the socket is not yet assigned to any transport.

This patch also adds the '.notify_buffer_size' callback in the
'struct virtio_transport' in order to inform the transport,
when the buffer_size is changed by the user. It is also useful
to limit the 'buffer_size' requested (e.g. virtio transports).

Acked-by: Dexuan Cui <decui@microsoft.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>

1 files changed, 11 insertions, 68 deletions

diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index b113619d9576..d4a0bf19aa98 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -456,17 +456,13 @@ int virtio_transport_do_socket_init(struct vsock_sock *vsk,
 	if (psk) {
 		struct virtio_vsock_sock *ptrans = psk->trans;
 
-		vvs->buf_size	= ptrans->buf_size;
-		vvs->buf_size_min = ptrans->buf_size_min;
-		vvs->buf_size_max = ptrans->buf_size_max;
 		vvs->peer_buf_alloc = ptrans->peer_buf_alloc;
-	} else {
-		vvs->buf_size = VIRTIO_VSOCK_DEFAULT_BUF_SIZE;
-		vvs->buf_size_min = VIRTIO_VSOCK_DEFAULT_MIN_BUF_SIZE;
-		vvs->buf_size_max = VIRTIO_VSOCK_DEFAULT_MAX_BUF_SIZE;
 	}
 
-	vvs->buf_alloc = vvs->buf_size;
+	if (vsk->buffer_size > VIRTIO_VSOCK_MAX_BUF_SIZE)
+		vsk->buffer_size = VIRTIO_VSOCK_MAX_BUF_SIZE;
+
+	vvs->buf_alloc = vsk->buffer_size;
 
 	spin_lock_init(&vvs->rx_lock);
 	spin_lock_init(&vvs->tx_lock);
@@ -476,71 +472,20 @@ int virtio_transport_do_socket_init(struct vsock_sock *vsk,
 }
 EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
 
-u64 virtio_transport_get_buffer_size(struct vsock_sock *vsk)
-{
-	struct virtio_vsock_sock *vvs = vsk->trans;
-
-	return vvs->buf_size;
-}
-EXPORT_SYMBOL_GPL(virtio_transport_get_buffer_size);
-
-u64 virtio_transport_get_min_buffer_size(struct vsock_sock *vsk)
+/* sk_lock held by the caller */
+void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val)
 {
 	struct virtio_vsock_sock *vvs = vsk->trans;
 
-	return vvs->buf_size_min;
-}
-EXPORT_SYMBOL_GPL(virtio_transport_get_min_buffer_size);
-
-u64 virtio_transport_get_max_buffer_size(struct vsock_sock *vsk)
-{
-	struct virtio_vsock_sock *vvs = vsk->trans;
-
-	return vvs->buf_size_max;
-}
-EXPORT_SYMBOL_GPL(virtio_transport_get_max_buffer_size);
-
-void virtio_transport_set_buffer_size(struct vsock_sock *vsk, u64 val)
-{
-	struct virtio_vsock_sock *vvs = vsk->trans;
+	if (*val > VIRTIO_VSOCK_MAX_BUF_SIZE)
+		*val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 
-	if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
-		val = VIRTIO_VSOCK_MAX_BUF_SIZE;
-	if (val < vvs->buf_size_min)
-		vvs->buf_size_min = val;
-	if (val > vvs->buf_size_max)
-		vvs->buf_size_max = val;
-	vvs->buf_size = val;
-	vvs->buf_alloc = val;
+	vvs->buf_alloc = *val;
 
 	virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
 					    NULL);
 }
-EXPORT_SYMBOL_GPL(virtio_transport_set_buffer_size);
-
-void virtio_transport_set_min_buffer_size(struct vsock_sock *vsk, u64 val)
-{
-	struct virtio_vsock_sock *vvs = vsk->trans;
-
-	if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
-		val = VIRTIO_VSOCK_MAX_BUF_SIZE;
-	if (val > vvs->buf_size)
-		vvs->buf_size = val;
-	vvs->buf_size_min = val;
-}
-EXPORT_SYMBOL_GPL(virtio_transport_set_min_buffer_size);
-
-void virtio_transport_set_max_buffer_size(struct vsock_sock *vsk, u64 val)
-{
-	struct virtio_vsock_sock *vvs = vsk->trans;
-
-	if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
-		val = VIRTIO_VSOCK_MAX_BUF_SIZE;
-	if (val < vvs->buf_size)
-		vvs->buf_size = val;
-	vvs->buf_size_max = val;
-}
-EXPORT_SYMBOL_GPL(virtio_transport_set_max_buffer_size);
+EXPORT_SYMBOL_GPL(virtio_transport_notify_buffer_size);
 
 int
 virtio_transport_notify_poll_in(struct vsock_sock *vsk,
@@ -632,9 +577,7 @@ EXPORT_SYMBOL_GPL(virtio_transport_notify_send_post_enqueue);
 
 u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk)
 {
-	struct virtio_vsock_sock *vvs = vsk->trans;
-
-	return vvs->buf_size;
+	return vsk->buffer_size;
 }
 EXPORT_SYMBOL_GPL(virtio_transport_stream_rcvhiwat);