Re: [PATCH net-next v03 4/6] hinic3: Add ethtool rss ops

[Mohsin Bashir <mohsin.bashr@gmail.com>]

>   /* hilink mac group command */
> diff --git a/drivers/net/ethernet/huawei/hinic3/hinic3_rss.c b/drivers/net/ethernet/huawei/hinic3/hinic3_rss.c
> index 25db74d8c7dd..1c8aea9d8887 100644
> --- a/drivers/net/ethernet/huawei/hinic3/hinic3_rss.c
> +++ b/drivers/net/ethernet/huawei/hinic3/hinic3_rss.c
> @@ -155,7 +155,7 @@ static int hinic3_set_rss_type(struct hinic3_hwdev *hwdev,
>   				       L2NIC_CMD_SET_RSS_CTX_TBL, &msg_params);
>   
>   	if (ctx_tbl.msg_head.status == MGMT_STATUS_CMD_UNSUPPORTED) {
> -		return MGMT_STATUS_CMD_UNSUPPORTED;
> +		return -EOPNOTSUPP;

Looks like an unrelated change?

>   	} else if (err || ctx_tbl.msg_head.status) {
>   		dev_err(hwdev->dev, "mgmt Failed to set rss context offload, err: %d, status: 0x%x\n",
>   			err, ctx_tbl.msg_head.status);
> @@ -165,6 +165,39 @@ static int hinic3_set_rss_type(struct hinic3_hwdev *hwdev,
>   	return 0;
>   }
>   



> +static int hinic3_set_rss_hash_opts(struct net_device *netdev,
> +				    struct ethtool_rxnfc *cmd)
> +{
> +	struct hinic3_nic_dev *nic_dev = netdev_priv(netdev);
> +	struct hinic3_rss_type *rss_type;
> +	int err;
> +
> +	rss_type = &nic_dev->rss_type;
> +
> +	if (!test_bit(HINIC3_RSS_ENABLE, &nic_dev->flags)) {
> +		cmd->data = 0;
> +		netdev_err(netdev, "RSS is disable, not support to set flow-hash\n");
> +		return -EOPNOTSUPP;
> +	}
> +
> +	/* RSS only supports hashing of IP addresses and L4 ports */
> +	if (cmd->data & ~(RXH_IP_SRC | RXH_IP_DST |
> +			  RXH_L4_B_0_1 | RXH_L4_B_2_3))
> +		return -EINVAL;
> +
> +	/* Both IP addresses must be part of the hash tuple */
> +	if (!(cmd->data & RXH_IP_SRC) || !(cmd->data & RXH_IP_DST))
> +		return -EINVAL;
> +
> +	err = hinic3_get_rss_type(nic_dev->hwdev, rss_type);
> +	if (err) {
> +		netdev_err(netdev, "Failed to get rss type\n");
> +		return err;
> +	}
> +
> +	err = hinic3_update_rss_hash_opts(netdev, cmd, rss_type);
> +	if (err)
> +		return err;
> +
> +	err = hinic3_set_rss_type(nic_dev->hwdev, *rss_type);

So if we fail here, we have already modified the rss_type in-place. From 
this on-wards, the HW state would diverge from in-memory state. How 
about use a local copy and only update if no error?

> +	if (err) {
> +		netdev_err(netdev, "Failed to set rss type\n");
> +		return err;
> +	}
> +
> +	return 0;
> +}
> +