kvm tools: Introduce struct net_dev_operations

virtio_net_{tx, rx}_thread can use ops->{tx, rx} to send and recevie
network package in both tap mode and user mode.

Suggested-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Asias He <asias.hejun@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/virtio/net.c b/tools/kvm/virtio/net.c
index 98d412041818eaf90eb80781e11e90b5f501cdba..3a9216d165b6c6b05493be4eb3b430230fff6fda 100644 (file)
--- a/tools/kvm/virtio/net.c
+++ b/tools/kvm/virtio/net.c
@@ -41,6 +41,13 @@ static struct pci_device_header pci_header = {
        .subsys_id                      = VIRTIO_ID_NET,
 };
 
+struct net_dev;
+
+struct net_dev_operations {
+       int (*rx)(struct iovec *iov, u16 in, struct net_dev *ndev);
+       int (*tx)(struct iovec *iov, u16 in, struct net_dev *ndev);
+};
+
 struct net_dev {
        pthread_mutex_t                 mutex;
 
@@ -68,9 +75,9 @@ struct net_dev {
        int                             mode;
 
        struct uip_info                 info;
+       struct net_dev_operations       *ops;
 };
 
-
 static struct net_dev ndev = {
        .mutex  = PTHREAD_MUTEX_INITIALIZER,
 
@@ -117,10 +124,7 @@ static void *virtio_net_rx_thread(void *p)
 
                        head = virt_queue__get_iov(vq, iov, &out, &in, kvm);
 
-                       if (ndev.mode == NET_MODE_TAP)
-                               len = readv(ndev.tap_fd, iov, in);
-                       else
-                               len = uip_rx(iov, in, &ndev.info);
+                       len = ndev.ops->rx(iov, in, &ndev);
 
                        virt_queue__set_used_elem(vq, head, len);
 
@@ -157,10 +161,7 @@ static void *virtio_net_tx_thread(void *p)
 
                        head = virt_queue__get_iov(vq, iov, &out, &in, kvm);
 
-                       if (ndev.mode == NET_MODE_TAP)
-                               len = writev(ndev.tap_fd, iov, out);
-                       else
-                               len = uip_tx(iov, out, &ndev.info);
+                       len = ndev.ops->tx(iov, out, &ndev);
 
                        virt_queue__set_used_elem(vq, head, len);
                }
@@ -412,6 +413,36 @@ static void virtio_net__io_thread_init(struct kvm *kvm)
        pthread_create(&ndev.io_tx_thread, NULL, virtio_net_tx_thread, (void *)kvm);
 }
 
+static inline int tap_ops_tx(struct iovec *iov, u16 out, struct net_dev *ndev)
+{
+       return writev(ndev->tap_fd, iov, out);
+}
+
+static inline int tap_ops_rx(struct iovec *iov, u16 in, struct net_dev *ndev)
+{
+       return readv(ndev->tap_fd, iov, in);
+}
+
+static inline int uip_ops_tx(struct iovec *iov, u16 out, struct net_dev *ndev)
+{
+       return uip_tx(iov, out, &ndev->info);
+}
+
+static inline int uip_ops_rx(struct iovec *iov, u16 in, struct net_dev *ndev)
+{
+       return uip_rx(iov, in, &ndev->info);
+}
+
+static struct net_dev_operations tap_ops = {
+       .rx     = tap_ops_rx,
+       .tx     = tap_ops_tx,
+};
+
+static struct net_dev_operations uip_ops = {
+       .rx     = uip_ops_rx,
+       .tx     = uip_ops_tx,
+};
+
 void virtio_net__init(const struct virtio_net_parameters *params)
 {
        struct ioevent ioevent;
@@ -430,10 +461,13 @@ void virtio_net__init(const struct virtio_net_parameters *params)
        pci__register(&pci_header, dev);
 
        ndev.mode = params->mode;
-       if (ndev.mode == NET_MODE_TAP)
+       if (ndev.mode == NET_MODE_TAP) {
                virtio_net__tap_init(params);
-       else
+               ndev.ops = &tap_ops;
+       } else {
                uip_init(&ndev.info);
+               ndev.ops = &uip_ops;
+       }
 
        virtio_net__io_thread_init(params->kvm);