Re: [dpdk-dev] [PATCH v8 8/9] ethdev: representor iterator compare complete info

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

On 3/4/2021 2:30 PM, Xueming Li wrote:
> The NIC can have multiple PCIe links and can be attached to multiple
> hosts, for example the same single NIC can be shared for multiple server
> units in the rack. On each PCIe link NIC can provide multiple PFs and
> VFs/SFs based on these ones. The full representor identifier consists of
> three indices - controller index, PF index, and VF or SF index (if any).
> 
> SR-IOV and SubFunction are created on top of PF. PF index is introduced
> because there might be multiple PFs in the bonding configuration and
> only bonding device is probed.
> 
> In eth representor comparator callback, ethdev representor ID was
> compared with devarg. Since controller index and PF index not compared,
> callback returned representor from other PF or controller.
> 
> This patch adds new API to get representor ID from controller, pf and
> vf/sf index. Representor comparer callback get representor ID then
> compare with device representor ID.
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>

<...>

> +int
> +rte_eth_representor_id_get(const struct rte_eth_dev *ethdev,
> +			   enum rte_eth_representor_type type,
> +			   int controller, int pf, int representor_port,
> +			   uint16_t *repr_id)
> +{
> +	int ret, n, i, count;
> +	struct rte_eth_representor_info *info = NULL;
> +	size_t size;
> +
> +	if (type == RTE_ETH_REPRESENTOR_NONE)
> +		return 0;
> +	if (repr_id == NULL)
> +		return -EINVAL;
> +
> +	/* Get PMD representor range info. */
> +	ret = rte_eth_representor_info_get(ethdev->data->port_id, NULL);
> +	if (ret < 0) {

This seems to support the legacy format, should the return value checked 
explicitly against the '-ENOTSUP', instead of any error?

> +		if (type == RTE_ETH_REPRESENTOR_VF && controller == -1 &&
> +		    pf == -1) {
> +			/* Direct mapping for legacy VF representor. */
> +			*repr_id = representor_port;
> +			return 0;
> +		} else {
> +			return ret;
> +		}
> +	}


<...>