sfc: Change filter ID generation to satisfy priority semantics of RX NFC
Also add note that the efx_filter_spec::priority field has nothing
to do with priority between multiple matching filters.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/sfc/filter.h b/drivers/net/ethernet/sfc/filter.h
index 872f213..dc9a256 100644
--- a/drivers/net/ethernet/sfc/filter.h
+++ b/drivers/net/ethernet/sfc/filter.h
@@ -78,6 +78,11 @@
*
* Use the efx_filter_set_*() functions to initialise the @type and
* @data fields.
+ *
+ * The @priority field is used by software to determine whether a new
+ * filter may replace an old one. The hardware priority of a filter
+ * depends on the filter type and %EFX_FILTER_FLAG_RX_OVERRIDE_IP
+ * flag.
*/
struct efx_filter_spec {
u8 type:4;