[dpdk-dev] [PATCH v6 5/6] bus: add helper to find a bus from a device name

[Gaëtan Rivet]

I made this API private, however we can see the bonding PMD could use
this kind of facility:

http://dpdk.org/ml/archives/dev/2017-July/070087.html

I know the failsafe could leverage this, as well as another bus idea I
threw together a few weeks ago[1].

So maybe I should make it public? This can always be fixed
past-integration though, and I'd prefer being able to go forward on the
PCI move.

[1]: http://dpdk.org/ml/archives/dev/2017-June/067546.html

On Tue, Jul 04, 2017 at 02:58:32AM +0200, Gaetan Rivet wrote:
> Find which bus should be able to parse this device name into an internal
> device representation.
> 
> Signed-off-by: Gaetan Rivet <gaetan.rivet at 6wind.com>
> ---
>  lib/librte_eal/common/eal_common_bus.c | 15 +++++++++++++++
>  lib/librte_eal/common/eal_private.h    | 12 ++++++++++++
>  2 files changed, 27 insertions(+)
> 
> diff --git a/lib/librte_eal/common/eal_common_bus.c b/lib/librte_eal/common/eal_common_bus.c
> index 87b0c6e..b143f21 100644
> --- a/lib/librte_eal/common/eal_common_bus.c
> +++ b/lib/librte_eal/common/eal_common_bus.c
> @@ -204,3 +204,18 @@ rte_bus_find_by_name(const char *busname)
>  {
>  	return rte_bus_find(NULL, cmp_bus_name, (const void *)busname);
>  }
> +
> +static int
> +bus_can_parse(const struct rte_bus *bus, const void *_name)
> +{
> +	const char *name = _name;
> +
> +	return !(bus->parse && bus->parse(name, NULL) == 0);
> +}
> +
> +/* find a bus capable of parsing a device description */
> +struct rte_bus *
> +rte_bus_find_by_device_name(const char *str)
> +{
> +	return rte_bus_find(NULL, bus_can_parse, str);
> +}
> diff --git a/lib/librte_eal/common/eal_private.h b/lib/librte_eal/common/eal_private.h
> index 6cacce0..0836339 100644
> --- a/lib/librte_eal/common/eal_private.h
> +++ b/lib/librte_eal/common/eal_private.h
> @@ -338,4 +338,16 @@ int rte_eal_hugepage_attach(void);
>   */
>  bool rte_eal_using_phys_addrs(void);
>  
> +/**
> + * Find a bus capable of identifying a device.
> + *
> + * @param str
> + *   A device identifier (PCI address, virtual PMD name, ...).
> + *
> + * @return
> + *   A valid bus handle if found.
> + *   NULL if no bus is able to parse this device.
> + */
> +struct rte_bus *rte_bus_find_by_device_name(const char *str);
> +
>  #endif /* _EAL_PRIVATE_H_ */
> -- 
> 2.1.4
> 

-- 
Gaëtan Rivet
6WIND