On Wed, 16 Oct 2019 23:03:12 +0200, Lorenzo Bianconi wrote:
> Implement XDP_TX verdict and ndo_xdp_xmit net_device_ops function
> pointer
>
> Signed-off-by: Lorenzo Bianconi <lore...@kernel.org>
> +static int
> +mvneta_xdp_submit_frame(struct mvneta_port *pp, struct mvneta_tx_queue *txq,
> + struct xdp_frame *xdpf, bool dma_map)
> +{
> + struct mvneta_tx_desc *tx_desc;
> + struct mvneta_tx_buf *buf;
> + dma_addr_t dma_addr;
> +
> + if (txq->count >= txq->tx_stop_threshold)
> + return MVNETA_XDP_DROPPED;
> +
> + tx_desc = mvneta_txq_next_desc_get(txq);
> +
> + buf = &txq->buf[txq->txq_put_index];
> + if (dma_map) {
> + /* ndo_xdp_xmit */
> + dma_addr = dma_map_single(pp->dev->dev.parent, xdpf->data,
> + xdpf->len, DMA_TO_DEVICE);
> + if (dma_mapping_error(pp->dev->dev.parent, dma_addr)) {
> + mvneta_txq_desc_put(txq);
> + return MVNETA_XDP_DROPPED;
> + }
> + buf->type = MVNETA_TYPE_XDP_NDO;
> + } else {
> + struct page *page = virt_to_page(xdpf->data);
> +
> + dma_addr = page_pool_get_dma_addr(page) +
> + xdpf->headroom + sizeof(*xdpf);
nit:
sizeof(*xdpf) + xdpf->headroom
order would be slightly preferable since it matches field ordering in
memory.
> + dma_sync_single_for_device(pp->dev->dev.parent, dma_addr,
> + xdpf->len, DMA_BIDIRECTIONAL);
> + buf->type = MVNETA_TYPE_XDP_TX;
> + }
> + buf->xdpf = xdpf;
> +
> + tx_desc->command = MVNETA_TXD_FLZ_DESC;
> + tx_desc->buf_phys_addr = dma_addr;
> + tx_desc->data_size = xdpf->len;
> +
> + mvneta_update_stats(pp, 1, xdpf->len, true);
> + mvneta_txq_inc_put(txq);
> + txq->pending++;
> + txq->count++;
> +
> + return MVNETA_XDP_TX;
> +}
