Re: [PATCH v3 1/4] net: Add support for hardware-offloadedencapsulation

From: David Miller
Date: Fri Dec 07 2012 - 14:37:15 EST


From: Joseph Gasparakis <joseph.gasparakis@xxxxxxxxx>
Date: Fri, 7 Dec 2012 11:41:46 -0800 (PST)

>
>
> On Fri, 7 Dec 2012, David Miller wrote:
>
>> From: Joseph Gasparakis <joseph.gasparakis@xxxxxxxxx>
>> Date: Fri, 7 Dec 2012 10:24:17 -0800 (PST)
>>
>> > So the idea here is that the driver will use the headers for checksumming
>> > if the skb->encapsulation bit is on. The bit should be set in the protocol
>> > driver.
>> >
>> > To answer the second comment, the flags that we use in this series of
>> > patches is NETIF_F_IP_CSUM, NETIF_F_IPV6_CSUM and NETIF_F_SG. These are
>> > the bits that we propose will be used for checksumming of encapsulation.
>> > As per a previous comment in v2, the hw_enc_features field should be used
>> > also in the future when NICs have more encap offloads, so one could
>> > indicate these features there from the driver.
>> >
>> > Furthermore, I submitted a patch for Rx checksumming, where NETIF_F_RXCSUM
>> > is used, again in conjunction with skb->encapsulation flag. As I mention
>> > in my logs, the driver is expected to set the ip_summed to UNNECESSARY and
>> > turn the skb->encapsulation on, to indicate that the inner headers are
>> > already HW checksummed.
>> >
>>
>> This is the kind of language that belongs in the commit message and
>> code comments.
>>
> Sure. I'll wait to gather some more feedback if there is any and I will
> re-spin this off adding more code comments and clarify this in the logs.

Great.

Please note that this request applies to your receive side change too.
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