From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olivier MATZ <olivier.matz@6wind.com>
Subject: Re: [PATCH v2 10/12] virtio: add Tx checksum offload
	support
Date: Thu, 13 Oct 2016 15:58:49 +0200
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To: Yuanhan Liu <yuanhan.liu@linux.intel.com>
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On 10/13/2016 10:38 AM, Yuanhan Liu wrote:
> On Mon, Oct 03, 2016 at 11:00:21AM +0200, Olivier Matz wrote:
>> +	/* Checksum Offload */
>> +	switch (cookie->ol_flags & PKT_TX_L4_MASK) {
>> +	case PKT_TX_UDP_CKSUM:
>> +		hdr->csum_start = cookie->l2_len + cookie->l3_len;
>> +		hdr->csum_offset = 6;
>> +		hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
>> +		break;
>> +
>> +	case PKT_TX_TCP_CKSUM:
>> +		hdr->csum_start = cookie->l2_len + cookie->l3_len;
>> +		hdr->csum_offset = 16;
>
> I would suggest to use "offsetof(...)" here, instead of some magic
> number like 16.

Will do, it's actually clearer.

Olivier