Re: skb_padto and small fragmented transmits

[Chris Leech]

On Thu, 2003-02-06 at 10:44, David S. Miller wrote:
>    From: Chris Leech <[e-mail]>
>    Date: 06 Feb 2003 11:22:51 -0800
>    
>    I fail to see how the statement "skb->len + skb->data_len" has any
>    usable meaning, or how it can be anything other than a bug.
> 
> This equation is the standard way to find the full length
> on any skb.  For linear skbs, data_len is always zero.
> 
> I asked Alan to use this formula so that greps on the source
> tree would always show data_len being taken into account, and
> thus usage would be consistent.

OK, now I'm really getting confused.  Every other example I can find in
the networking code, and every scatter-gather capable driver, uses
skb->len as the full length and skb->len - skb->data_len as the length
of the first or linear portion.