linux网卡数据流 发送与接收

标签：linux网卡数据流   linux网卡数据发送与接收   网卡数据流   

通常网卡驱动代码量比较大，但是都离不开发送与接收，掌握好骨干也就好理解与调试了。

net_device_ops结构题的填充，在里实现了open与发送等操作：

static const struct net_device_ops xxx_netdev_ops = {
    .ndo_open = xxx_net_open,
    .ndo_stop = xxx_net_stop,
    .ndo_start_xmit = xxx_start_xmit,
    .ndo_get_stats =  xxx_get_stats,
    .ndo_tx_timeout = xxx_tx_timeout,
};


   static int xxx_start_xmit(struct sk_buff *skb, struct net_device *dev){

   ---------
    nwrite = filep->f_op->write(filep, skb->data, skb->len, &filep->f_pos);
    set_fs(old_fs);

    if (nwrite == skb->len) {
        priv->stats.tx_packets++;
        priv->stats.tx_bytes +=skb->len;
        priv->netdev->trans_start = jiffies;
    }
    -----------
}

static int xxx_submit_skb(void *data)
{
    --------
    skb = netdev_alloc_skb(ndev, pkt_len + NET_IP_ALIGN); /* NET_IP_ALIGN is 2 */
    if (!skb) {
        printk(KERN_INFO "error: out of memory for rx'd frame\n");
        priv->stats.rx_dropped++;
        ret = -ENOMEM;
        goto error;
    } 

    skb_reserve(skb, NET_IP_ALIGN);

    memcpy(（skb_put(skb, pkt_len), pkt_len),buf,sizeof(buf);
    
    skb->dev = priv->netdev;
    skb->protocol = eth_type_trans(skb, priv->netdev);
    priv->stats.rx_packets++;
    priv->stats.rx_bytes += pkt_len;
    ret = netif_rx(skb);
    if (ret != 0)
        printk(KERN_INFO "%s: netif_rx error\n", __func__);

    --------
}

linux网卡数据流 发送与接收

标签：linux网卡数据流   linux网卡数据发送与接收   网卡数据流   

原文地址：http://blog.csdn.net/linux_devices_driver/article/details/39033351