On 13/07/2015 07:46, Jason Wang wrote:
> - if (out_sg[0].iov_len < n->guest_hdr_len) {
> + s = iov_to_buf(out_sg, out_num, 0, &hdr, sizeof(hdr));
> + if (s != sizeof(hdr)) {
> error_report("virtio-net header incorrect");
> exit(1);
> }
> - virtio_net_hdr_swap(vdev, (void *) out_sg[0].iov_base);
> + virtio_net_hdr_swap(vdev, (void *) &hdr);
> + s = iov_from_buf(out_sg, out_num, 0, &hdr, sizeof(hdr));
> + assert(s == sizeof(hdr));
> }
Are the copies necessary in the common case of no swap? In that case
you can just use iov_size.
Paolo
