build_skb - build a network buffer
2. SYNOPSIS ▲
struct sk_buff * build_skb(void * data , unsigned int frag_size );
3. ARGUMENTS ▲
data buffer provided by caller
size of fragment, or 0 if head was kmalloced
4. DESCRIPTION ▲
Allocate a new sk_buff. Caller provides space holding head and skb_shared_info. data must have been allocated by kmalloc The return is the new skb buffer. On a failure the return is NULL, and data is not freed.
5. NOTES ▲
Before IO, driver allocates only data buffer where NIC put incoming frame Driver should add room at head (NET_SKB_PAD) and MUST add room at tail (SKB_DATA_ALIGN(skb_shared_info)) After IO, driver calls build_skb, to allocate sk_buff and populate it before giving packet to stack. RX rings only contains data buffers, not full skbs.
6. COPYRIGHT ▲