Subject: Re: Small Ethernet packet padding
To: None <>
From: Jason Thorpe <>
List: tech-net
Date: 10/31/2004 06:42:54
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On Oct 31, 2004, at 3:18 AM, wrote:

> Also, I wonder what is the gain of making the padding at
> the driver level.  I'd like some input there too.  If
> there is no actual advantage to doing that inside the
> hardware driver, I think it would be best to convert all
> affected drivers to such a scheme as the low-level padding
> adds quite some complexity to the driver.

Some hardware will auto-pad.  You want to take advantage of this when 
possible.  Perhaps a common subroutine that drivers can call is 
appropriate.  OTOH, letting the driver pad also allows the driver to 
e.g. pre-compute a DMA address of a zero'd area for this purpose.

         -- Jason R. Thorpe <>

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