uapi: ioam6: API for netlink multicast events

Add new api to support ioam6 events for generic netlink multicast. A
first "trace" event is added to the list of ioam6 events, which will
represent an IOAM Pre-allocated Trace Option-Type. It provides another
solution to share IOAM data with user space.
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/ioam6_genl.h

@@ -49,4 +49,24 @@ enum {
 
 #define IOAM6_CMD_MAX (__IOAM6_CMD_MAX - 1)
 
+#define IOAM6_GENL_EV_GRP_NAME "ioam6_events"
+
+enum ioam6_event_type {
+	IOAM6_EVENT_UNSPEC,
+	IOAM6_EVENT_TRACE,
+};
+
+enum ioam6_event_attr {
+	IOAM6_EVENT_ATTR_UNSPEC,
+
+	IOAM6_EVENT_ATTR_TRACE_NAMESPACE,	/* u16 */
+	IOAM6_EVENT_ATTR_TRACE_NODELEN,		/* u8 */
+	IOAM6_EVENT_ATTR_TRACE_TYPE,		/* u32 */
+	IOAM6_EVENT_ATTR_TRACE_DATA,		/* Binary */
+
+	__IOAM6_EVENT_ATTR_MAX
+};
+
+#define IOAM6_EVENT_ATTR_MAX (__IOAM6_EVENT_ATTR_MAX - 1)
+
 #endif /* _UAPI_LINUX_IOAM6_GENL_H */