sfc: Add flag for stack-owned RX MAC filters

MAC filters inserted on request from the stack (ndo_set_rx_mode)
should allow manual steering but not removal.  Currently we have a
special case for Siena's all-multicast and all-unicast MAC filters,
but on EF10 we need to allow for steering of precise MAC filters as
well.

The EFX_FILTER_FLAG_RX_STACK flag changes the behaviour of replacement
and removal requests:

- Replacement *of* a filter with this flag never clears the flag but
  does change steering and saved priority
- Replacement *by* a filter with this flag only sets the flag but does
  not change steering
- Removal with priority < EFX_FILTER_PRI_REQUIRED really resets RX
  steering and saved priority

This could support precise MAC filtering on Siena in future.

As a side-benefit, the default MAC filters are hidden from ethtool
until they are steered.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/net/ethernet/sfc/filter.h b/drivers/net/ethernet/sfc/filter.h
index 1b410defccec..e459e43a2798 100644
--- a/drivers/net/ethernet/sfc/filter.h
+++ b/drivers/net/ethernet/sfc/filter.h
@@ -78,12 +78,19 @@ enum efx_filter_priority {
  *	according to the indirection table.
  * @EFX_FILTER_FLAG_RX_SCATTER: Enable DMA scatter on the receiving
  *	queue.
+ * @EFX_FILTER_FLAG_RX_STACK: Indicates a filter inserted for the
+ *	network stack.  The filter must have a priority of
+ *	%EFX_FILTER_PRI_REQUIRED.  It can be steered by a replacement
+ *	request with priority %EFX_FILTER_PRI_MANUAL, and a removal
+ *	request with priority %EFX_FILTER_PRI_MANUAL will reset the
+ *	steering (but not remove the filter).
  * @EFX_FILTER_FLAG_RX: Filter is for RX
  * @EFX_FILTER_FLAG_TX: Filter is for TX
  */
 enum efx_filter_flags {
 	EFX_FILTER_FLAG_RX_RSS = 0x01,
 	EFX_FILTER_FLAG_RX_SCATTER = 0x02,
+	EFX_FILTER_FLAG_RX_STACK = 0x04,
 	EFX_FILTER_FLAG_RX = 0x08,
 	EFX_FILTER_FLAG_TX = 0x10,
 };