how to get "max # of mbufs in a packet" from xn to the tcp stack?

[Colin Percival]

Hi all,

I've attached a patch which fixes the "nfrags > 18, netback won't be able to
handle it" problem with xen netfront when TSO is enabled.

It's not finished, though:
+	int max_mbuf_chain_len = 16;	/* XXX Set this based on interface? */

I'm not sure what the right way is to feed a value from the interface up into
tcp_output; can someone advise?

-- 
Colin Percival
Security Officer, FreeBSD | freebsd.org | The power to serve
Founder / author, Tarsnap | tarsnap.com | Online backups for the truly paranoid
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