Subject: Re: [Xen-devel] [PATCH net-next v2 2/2] xen-netback: Grant copy the header instead of map and memcpy

From: Zoltan Kiss <[email-masked]>
Date: Wed, 2 Apr 2014 15:41:38 +0100

On 02/04/14 14:11, David Vrabel wrote:
> On 01/04/14 12:40, Ian Campbell wrote:
>> On Mon, 2014-03-31 at 16:08 +0100, Zoltan Kiss wrote:
>>>
>>>   		__skb_put(skb, data_len);
>>> +		vif->tx_copy_ops[*copy_ops].source.u.ref = txreq.gref;
>>> +		vif->tx_copy_ops[*copy_ops].source.domid = vif->domid;
>>> +		vif->tx_copy_ops[*copy_ops].source.offset = txreq.offset;
>>> +
>>> +		vif->tx_copy_ops[*copy_ops].dest.u.gmfn =
>>> +			virt_to_mfn(skb->data);
>>> +		vif->tx_copy_ops[*copy_ops].dest.domid = DOMID_SELF;
>>> +		vif->tx_copy_ops[*copy_ops].dest.offset =
>>> +			offset_in_page(skb->data);
>>> +
>>> +		vif->tx_copy_ops[*copy_ops].len = data_len;
>>> +		vif->tx_copy_ops[*copy_ops].flags = GNTCOPY_source_gref;
>>
>> We have gnttab_set_map_op. Should we have gnttap_set_copy_op too?
>
> A set of 3 might be useful I think.
>
> gnttab_set_copy_op_ref_to_gfn()
> gnttab_set_copy_op_gfn_to_ref()
> gnttab_set_copy_op_ref_to_ref()
I doubt it would increase clarity in any way, but I'll send a patch on 
top of these.

Zoli