[dpdk-dev] [PATCH v9] dmadev: introduce DMA device library

[Bruce Richardson]

On Tue, Jul 20, 2021 at 07:12:52PM +0800, Chengwen Feng wrote:
> This patch introduce 'dmadevice' which is a generic type of DMA
> device.
> 
> The APIs of dmadev library exposes some generic operations which can
> enable configuration and I/O with the DMA devices.
> 
> Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>

Apologies for late feedback. Just reporting issues as I find them working
with the code.

/Bruce

> ---
<snip>
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Returns the number of operations that have been completed, and the
> + * operations result may succeed or fail.
> + *
> + * @param dev_id
> + *   The identifier of the device.
> + * @param vchan
> + *   The identifier of virtual DMA channel.
> + * @param nb_cpls
> + *   Indicates the size of status array.
> + * @param[out] last_idx
> + *   The last completed operation's index.
> + *   If not required, NULL can be passed in.
> + * @param[out] status
> + *   The error code of operations that completed.
> + *   @see enum rte_dma_status_code

The documentation should make it clear that this is an array with "nb_cpls"
entries.

> + *
> + * @return
> + *   The number of operations that completed. This return value must be less
> + *   than or equal to the value of nb_cpls.

also update this to report that the appropriate number of "status" entries
have been filled out.

> + */
> +__rte_experimental
> +static inline uint16_t
> +rte_dmadev_completed_status(uint16_t dev_id, uint16_t vchan,
> +			    const uint16_t nb_cpls, uint16_t *last_idx,
> +			    enum rte_dma_status_code *status)
<snip>