struct net_device *alloc_netdev(int sizeof_priv, const char *name,
void (*setup)(structnet_device *));
Here, sizeof_priv is the size of the driver’s “private data” area; with network devices, that area is allocated along with the net_device structure. In fact, the two are allocated together in one large chunk of memory, but driver authors should pretend that they don’t know that. name is the name of this interface.
