centos man page for skb_seq_read

SKB_SEQ_READ(9) 						 Linux Networking						   SKB_SEQ_READ(9)

NAME
       skb_seq_read - Sequentially read skb data

SYNOPSIS
       unsigned int skb_seq_read(unsigned int consumed, const u8 ** data, struct skb_seq_state * st);

ARGUMENTS
       consumed
	   number of bytes consumed by the caller so far

       data
	   destination pointer for data to be returned

       st
	   state variable

DESCRIPTION
       Reads a block of skb data at consumed relative to the lower offset specified to skb_prepare_seq_read. Assigns the head of the data block to
       data and returns the length of the block or 0 if the end of the skb data or the upper offset has been reached.

       The caller is not required to consume all of the data returned, i.e.  consumed is typically set to the number of bytes already consumed and
       the next call to skb_seq_read will return the remaining part of the block.

NOTE 1
       The size of each block of data returned can be arbitrary, this limitation is the cost for zerocopy seqeuental reads of potentially non
       linear data.

NOTE 2
       Fragment lists within fragments are not implemented at the moment, state->root_skb could be replaced with a stack for this purpose.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014							   SKB_SEQ_READ(9)