On Mon, 19 Oct 2015 16:56:02 +0000 "Xie, Huawei" <huawei.xie at intel.com> wrote:
> On 10/20/2015 12:43 AM, Stephen Hemminger wrote: > > On Mon, 19 Oct 2015 16:28:30 +0000 > > "Xie, Huawei" <huawei.xie at intel.com> wrote: > > > >> On 10/19/2015 1:16 PM, Stephen Hemminger wrote: > >>> Virtio supports a feature that allows sender to put transmit > >>> header prepended to data. It requires that the mbuf be writeable, correct > >>> alignment, and the feature has been negotiatied. If all this works out, > >>> then it will be the optimum way to transmit a single segment packet. > >> "When using legacy interfaces, transitional drivers which have not > >> negotiated VIRTIO_F_ANY_LAYOUT > >> MUST use a single descriptor for the struct virtio_net_hdr on both > >> transmit and receive, with the > >> network data in the following descriptors." > > The code checks for the any layout feature, what is the problem? > My reply is removed. I said virtio RX is already implemented using this > feature by default without negotiation(at the time of implementation, no > idea of this feature), is the RX implementation wrong? > No receiver is fine, it is okay to handle it coming in as long as it doesn't assume that is the only possible layout.
