Red Hat Blog: vDPA kernel framework part 3: usage for VMs and containers

This MMIO write will be forward to the vhost-vDPA driver by KVM via ioeventfd. The vhost-vDPA driver will use a dedicated vDPA bus operation to touch the doorbell of the real hardware through the vDPA VF driver. The vDPA device (vDPA VF in the above figure) will start the datapath and send the packet to the wire through DMA from the buffer pointed in the virtqueue.