[dpdk-dev] [PATCH v25 2/6] dmadev: add control plane API support

[Bruce Richardson]

On Mon, Oct 11, 2021 at 03:33:44PM +0800, Chengwen Feng wrote:
> This patch add control plane API for dmadev.
> 
> Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
> Acked-by: Bruce Richardson <bruce.richardson at intel.com>
> Acked-by: Morten Brørup <mb at smartsharesystems.com>
> Reviewed-by: Kevin Laatz <kevin.laatz at intel.com>
> Reviewed-by: Conor Walsh <conor.walsh at intel.com>
> ---
>  doc/guides/prog_guide/dmadev.rst       |  38 ++
>  doc/guides/rel_notes/release_21_11.rst |   1 +
>  lib/dmadev/rte_dmadev.c                | 360 +++++++++++++++++++
>  lib/dmadev/rte_dmadev.h                | 464 +++++++++++++++++++++++++
>  lib/dmadev/rte_dmadev_pmd.h            |  61 ++++
>  lib/dmadev/version.map                 |   9 +
>  6 files changed, 933 insertions(+)
> 

<snip>

> +/**
> + * A structure used to retrieve the information of a DMA device.
> + *
> + * @see rte_dma_info_get
> + */
> +struct rte_dma_info {
> +	/** Device capabilities (RTE_DMA_CAPA_*). */
> +	uint64_t dev_capa;
> +	/** Maximum number of virtual DMA channels supported. */
> +	uint16_t max_vchans;
> +	/** Maximum allowed number of virtual DMA channel descriptors. */
> +	uint16_t max_desc;
> +	/** Minimum allowed number of virtual DMA channel descriptors. */
> +	uint16_t min_desc;
> +	/** Maximum number of source or destination scatter-gather entry
> +	 * supported.
> +	 * If the device does not support COPY_SG capability, this value can be
> +	 * zero.
> +	 * If the device supports COPY_SG capability, then rte_dma_copy_sg()
> +	 * parameter nb_src/nb_dst should not exceed this value.
> +	 */
> +	uint16_t max_sges;
> +	/** NUMA node connection, -1 if unknown. */
> +	int16_t numa_node;
> +	/** Number of virtual DMA channel configured. */
> +	uint16_t nb_vchans;
> +};
> +
Since we really don't want apps to have to access the rte_dma_devices
array, I think we should add "const char *name" to the info struct. Apps may
find it useful for debugging or logging, and certainly the unit tests will
use it.

/Bruce