Re: Source code compatibility in Stable series????

[Andi Kleen]

On Fri, May 11, 2001 at 02:56:35AM -0700, David S. Miller wrote:
> 
> Rogier Wolff writes:
>  > It seems that in 2.4.4 suddenly the function "skb_cow" no longer
>  > returns the modified skb, but it retuns and integer for
>  > succes/failure.
>  > 
>  > This means that for networking modules requiring this function, there
>  > is no source code compatibilty between 2.4.3 and 2.4.4.
> 
> And skb_datarefp went away too, in fact a ton of things changes.
> 
> Just deal with it.

I guess it would be possible to add a HAVE_ZEROCOPY to skbuff.h to make
it a bit easier for single source drivers.

--- include/linux/skbuff.h-o	Wed May  9 12:36:44 2001
+++ include/linux/skbuff.h	Fri May 11 12:12:43 2001
@@ -29,6 +29,7 @@
 #define HAVE_ALLOC_SKB		/* For the drivers to know */
 #define HAVE_ALIGNABLE_SKB	/* Ditto 8)		   */
 #define SLAB_SKB 		/* Slabified skbuffs 	   */
+#define HAVE_ZEROCOPY		/* Zerocopy stack */ 
 
 #define CHECKSUM_NONE 0
 #define CHECKSUM_HW 1

-Andi