From owner-freebsd-net@freebsd.org  Wed Jun  8 11:36:18 2016
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Date: Wed, 8 Jun 2016 13:28:28 +0200 (CEST)
From: tom.barbette@ulg.ac.be
To: Luigi Rizzo <rizzo@iet.unipi.it>
Cc: "Andrey V. Elsukov" <bu7cher@yandex.ru>, 
 Andrew Vylegzhanin <avv314@gmail.com>, freebsd-net@freebsd.org, 
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Subject: Re: Is netmap jumbo frames broken in STABLE?
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Support for fragmented packets with ixgbe was recently added on the linux version of Netmap :

https://github.com/luigirizzo/netmap/commit/fc1e77560a8a8ea93cc3594de5fae94334debcd3

I think the change for freebsd would be quite the same looking at https://github.com/freebsd/freebsd/blob/master/sys/dev/netmap/ixgbe_netmap.h#L396

After that, your userspace application simply have to check for the NS_MOREFRAG flag in the receive ring, and if it's set he knows the end of the packet will follow in the next buf.

Tom