Re: [dpdk-dev] [PATCH] net/bnx2x: reserve enough headroom for mbuf prepend

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 2/6/2018 11:21 AM, zhouyangchao wrote:

Can you please provide more information why this patch is needed?

> Signed-off-by: Yangchao Zhou <zhouyates@gmail.com>
> ---
>  drivers/net/bnx2x/bnx2x_rxtx.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/bnx2x/bnx2x_rxtx.c b/drivers/net/bnx2x/bnx2x_rxtx.c
> index a0d4ac9..d8a3225 100644
> --- a/drivers/net/bnx2x/bnx2x_rxtx.c
> +++ b/drivers/net/bnx2x/bnx2x_rxtx.c
> @@ -140,7 +140,8 @@ bnx2x_dev_rx_queue_setup(struct rte_eth_dev *dev,
>  			return -ENOMEM;
>  		}
>  		rxq->sw_ring[idx] = mbuf;
> -		rxq->rx_ring[idx] = mbuf->buf_iova;
> +		rxq->rx_ring[idx] = 
> +			rte_cpu_to_le_64(rte_mbuf_data_iova_default(mbuf));
>  	}
>  	rxq->pkt_first_seg = NULL;
>  	rxq->pkt_last_seg = NULL;
> @@ -400,7 +401,8 @@ bnx2x_recv_pkts(void *p_rxq, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
>  
>  		rx_mb = rxq->sw_ring[bd_cons];
>  		rxq->sw_ring[bd_cons] = new_mb;
> -		rxq->rx_ring[bd_prod] = new_mb->buf_iova;
> +		rxq->rx_ring[bd_prod] = 
> +			rte_cpu_to_le_64(rte_mbuf_data_iova_default(new_mb));
>  
>  		rx_pref = NEXT_RX_BD(bd_cons) & MAX_RX_BD(rxq);
>  		rte_prefetch0(rxq->sw_ring[rx_pref]);
> @@ -409,7 +411,7 @@ bnx2x_recv_pkts(void *p_rxq, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
>  			rte_prefetch0(&rxq->sw_ring[rx_pref]);
>  		}
>  
> -		rx_mb->data_off = pad;
> +		rx_mb->data_off = pad + RTE_PKTMBUF_HEADROOM;
>  		rx_mb->nb_segs = 1;
>  		rx_mb->next = NULL;
>  		rx_mb->pkt_len = rx_mb->data_len = len;
>