From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Liu <wei.liu2@citrix.com>
Subject: Re: [PATCH net-next RFC 3/5] xen-netback: Remove old TX grant copy
 definitons
Date: Wed, 30 Oct 2013 11:13:18 +0000
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On Wed, Oct 30, 2013 at 12:50:18AM +0000, Zoltan Kiss wrote:
> These became obsolate with grant mapping.
> 

I'm afraid not.

This TX coalescing mechanism is designed to handle the situation where
guest's MAX_SKB_FRAGS > host's MAX_SKB_FRAGS.

To a further extent, I think you might need to add mechanism for backend
to tell frontend how many frags it can handle, and frontend needs to do
necessary coalescing. Until then you can safely use this new mapping
scheme.

Wei.