Re: [PATCH 10/13] net: add paged frag destructor to skb_fill_page_desc()

[Ian Campbell <Ian.Campbell@eu.citrix.com>]

On Fri, 2011-07-22 at 20:58 +0100, Michał Mirosław wrote:
> 2011/7/22 Ian Campbell <ian.campbell@citrix.com>:
> > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
> > index 9818fe2..faee8d3 100644
> > --- a/include/linux/skbuff.h
> > +++ b/include/linux/skbuff.h
> > @@ -1134,12 +1134,14 @@ static inline int skb_pagelen(const struct sk_buff *skb)
> >  * Does not take any additional reference on the fragment.
> >  */
> >  static inline void __skb_fill_page_desc(struct sk_buff *skb, int i,
> > -                                       struct page *page, int off, int size)
> > +                                       struct page *page,
> > +                                       struct skb_frag_destructor *destroy,
> > +                                       int off, int size)
> >  {
> >        skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
> >
> >        frag->page.p              = page;
> > -       frag->page.destructor     = NULL;
> > +       frag->page.destructor     = destroy;
> >        frag->page_offset         = off;
> >        frag->size                = size;
> >  }
> 
> You could just rename this function to e.g.
> __skb_fill_fragile_page_desc() (or whatever name) add an inline
> wrapper calling it with destroy == NULL. This will avoid touching all
> those drivers which won't ever need this functionality.

I could call this variant __skb_frag_init (which I think better fits
into the pattern of the new functions) and leave the existing
__skb_fill_page_desc as a compat wrapper if that's preferred but I was
trying to avoid duplicating up constructors just for different sets of
defaults.
 
Ian.