[dpdk-dev] [RFC 2/9] ethdev: move queue id check in generic layer

[Ferruh Yigit]

On 11/24/2016 9:54 AM, Olivier Matz wrote:
> The check of queue_id is done in all drivers implementing
> rte_eth_rx_queue_count(). Factorize this check in the generic function.
> 
> Note that the nfp driver was doing the check differently, which could
> induce crashes if the queue index was too big.
> 
> By the way, also move the is_supported test before the port valid and
> queue valid test.
> 
> PR=52423
> Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
> Acked-by: Ivan Boule <ivan.boule at 6wind.com>
> ---

<...>

> diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
> index c3edc23..9551cfd 100644
> --- a/lib/librte_ether/rte_ethdev.h
> +++ b/lib/librte_ether/rte_ethdev.h
> @@ -2693,7 +2693,7 @@ rte_eth_rx_burst(uint8_t port_id, uint16_t queue_id,
>   *  The queue id on the specific port.
>   * @return
>   *  The number of used descriptors in the specific queue, or:
> - *     (-EINVAL) if *port_id* is invalid
> + *     (-EINVAL) if *port_id* or *queue_id* is invalid
>   *     (-ENOTSUP) if the device does not support this function
>   */
>  static inline int
> @@ -2701,8 +2701,10 @@ rte_eth_rx_queue_count(uint8_t port_id, uint16_t queue_id)
>  {
>  	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
>  
> -	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
>  	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_count, -ENOTSUP);
> +	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);

Doing port validity check before accessing dev->dev_ops->rx_queue_count
can be good idea.

What about validating port_id even before accessing
rte_eth_devices[port_id]?

> +	if (queue_id >= dev->data->nb_rx_queues)
> +		return -EINVAL;
>  
>  	return (*dev->dev_ops->rx_queue_count)(dev, queue_id);
>  }
>