Man page 9 : skb_fill_page_desc

skb_fill_page_desc - initialise a paged fragment in an skb

void skb_fill_page_desc(struct sk_buff *  skb , int  i , struct page *  page , int  off , int  size );

skb
    buffer containing fragment to be initialised

i
    paged fragment index to initialise

page
    the page to use for this fragment

off
    the offset to the data with page

size
    the length of the data

As per __skb_fill_page_desc -- initialises the iAqth fragment of skb to point to size bytes at offset off within page. In addition updates skb such that i is the last fragment.

Does not take any additional reference on the fragment.