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Date: Fri, 3 Feb 2006 11:20:21 +0300
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: kamal kc <kamal_ckk@yahoo.com>
Message-ID: <20060203082021.GL60276@FreeBSD.org>
Mail-Followup-To: Gleb Smirnoff <glebius@FreeBSD.org>,
	kamal kc <kamal_ckk@yahoo.com>, freebsd <freebsd-net@freebsd.org>
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Cc: freebsd <freebsd-net@FreeBSD.org>
Subject: Re: offloading ip checksum calculation to the NIC
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On Thu, Feb 02, 2006 at 10:20:46PM -0800, kamal kc wrote:
k> i want to offload ip checksum calculation to the NIC.
k> I use 3Com 3c905B-TX NIC cards.
k> 
k> I found that there are variables::>>
k> 
k>         int	csum_flags;		/* flags regarding checksum */
k> 	int	csum_data;		/* data field used by csum routines */
k> 
k> in struct pkthdr in mbuf.h.
k> 
k> also i found the various flags for the hardware checksumming.
k> but i don't know the exact steps i need to do 
k> in order to offload checksumming. 
k> 
k> should i set the csum_flags to CSUM_IP and point
k> csum_data to the start of the ip header ??
k> 
k> it would be a great help if anybody
k> could tell me what do i need to do ?

afaik, the xl(4) driver already supports checksum calculation.

-- 
Totus tuus, Glebius.
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