netif.h contains a specification of the XEN_NETIF_EXTRA_TYPE_MCAST_{ADD,DEL}
extra info messages require to manipulate a multicast filter list maintained
by a backend but does not specify how the multicast contol feature should
be negotiated in xenstore. This patch attempts to rectify that.To determine the correct sequence I mined the xen-devel archives to ascertain the intention of the original submitter of the patch (see thread starting at http://lists.xenproject.org/archives/html/xen-devel/2007-11/msg00687.html) and also examined how the feature is implemented by the illumos xnb/xnf drivers, which I believe form the only concrete example. Signed-off-by: Paul Durrant <paul.durr...@citrix.com> Cc: Ian Campbell <ian.campb...@citrix.com> Cc: Ian Jackson <ian.jack...@eu.citrix.com> Cc: Jan Beulich <jbeul...@suse.com> Cc: Keir Fraser <k...@xen.org> Cc: Tim Deegan <t...@xen.org> --- xen/include/public/io/netif.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/xen/include/public/io/netif.h b/xen/include/public/io/netif.h index 353eab7..6599c5a 100644 --- a/xen/include/public/io/netif.h +++ b/xen/include/public/io/netif.h @@ -136,6 +136,19 @@ */ /* + * "feature-multicast-control" advertises the capability to filter ethernet + * multicast packets in the backend. To enable use of this capability the + * frontend must set "request-multicast-control" before moving into the + * connected state. + * If "request-multicast-control" is set then the backend transmit side should + * drop any multicast packet that does not match in a filter list. The list is + * amended by the frontend by sending XEN_NETIF_EXTRA_TYPE_MCAST_{ADD,DEL} + * messages as specified below. + * Once enabled by the frontend, the feature cannot be disabled except by + * closing and re-connecting to the backend. + */ + +/* * This is the 'wire' format for packets: * Request 1: netif_tx_request_t -- NETTXF_* (any flags) * [Request 2: netif_extra_info_t] (only if request 1 has NETTXF_extra_info) -- 1.7.10.4 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
