Re: [PATCH net-next] ipmr: ip6mr: Create new sockopt to clear mfc cache or vifs

[Nicolas Dichtel <nicolas.dichtel@6wind.com>]

Le 08/02/2019 à 05:11, Callum Sinclair a écrit :
> Currently the only way to clear the mfc cache was to delete the entries
mfc stands for 'multicast forwarding cache', so 'mfc cache' is a bit strange.

> one by one using the MRT_DEL_MFC socket option or to destroy and
> recreate the socket.
Note that if entries were added with MRT_ADD_MFC_PROXY, they will survive to the
socket destruction. This is not the case with your new cmd. Is it intended?
Maybe a third option (something like MRT_FLUSH_MFC_PROXY) would be useful to
avoid confusion?

> 
> Create a new socket option which will clear the multicast forwarding
> cache on the socket without destroying the socket. The new socket option
> MRT_FLUSH_ENTRIES will clear all multicast entries on the sockets table
> and the MRT_FLUSH_VIFS will delete all multicast vifs on the socket
> table.
> 
> Signed-off-by: Callum Sinclair <callum.sinclair@alliedtelesis.co.nz>
> ---
>  include/uapi/linux/mroute.h  |  7 +++-
>  include/uapi/linux/mroute6.h |  7 +++-
>  net/ipv4/ipmr.c              | 69 ++++++++++++++++++++-------------
>  net/ipv6/ip6mr.c             | 74 ++++++++++++++++++++++--------------
>  4 files changed, 100 insertions(+), 57 deletions(-)
> 
> diff --git a/include/uapi/linux/mroute.h b/include/uapi/linux/mroute.h
> index 5d37a9ccce63..673495ca3495 100644
> --- a/include/uapi/linux/mroute.h
> +++ b/include/uapi/linux/mroute.h
> @@ -28,12 +28,17 @@
>  #define MRT_TABLE	(MRT_BASE+9)	/* Specify mroute table ID		*/
>  #define MRT_ADD_MFC_PROXY	(MRT_BASE+10)	/* Add a (*,*|G) mfc entry	*/
>  #define MRT_DEL_MFC_PROXY	(MRT_BASE+11)	/* Del a (*,*|G) mfc entry	*/
> -#define MRT_MAX		(MRT_BASE+11)
> +#define MRT_FLUSH	(MRT_BASE+12)	/* Flush all multicast entries and vifs	*/
nit: "Flush all mfc entries and/or vifs" ?

> +#define MRT_MAX		(MRT_BASE+12)
>  
>  #define SIOCGETVIFCNT	SIOCPROTOPRIVATE	/* IP protocol privates */
>  #define SIOCGETSGCNT	(SIOCPROTOPRIVATE+1)
>  #define SIOCGETRPF	(SIOCPROTOPRIVATE+2)
>  
> +/* MRT_FLUSH optional flags */
> +#define MRT_FLUSH_ENTRIES	1	/* For flushing all multicast entries */
Maybe MRT_FLUSH_MFC is more consistent with the previous naming (MRT_ADD_MFC, etc.)


Regards,
Nicolas