igc: Refactor ethertype filtering code

The whole ethertype filtering code is implemented in igc_ethtool.c and
mixes logic from ethtool and core parts. This patch refactors it so core
logic is moved to igc_main.c, aligning the ethertype filtering code
organization with the rest of the filtering code from the driver (MAC
address and VLAN priority).

Besides moving code to igc_main.c, this patch also does some minor
improvements to the code. Below are some highlights.

In case all filters are already in use and the user tries to add another
filter, we return -ENOSPC instead of -EINVAL so a more meaningful error
code is provided. This also aligns with the behavior implemented in MAC
address filtering code.

With this code refactoring, 'etype_bitmap' array in struct igc_adapter
and 'etype_reg_index' in struct igc_nfc_filter are not needed anymore
and are removed.

Log messages are added to help debugging the ethertype filtering code.

Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 8 insertions, 59 deletions

diff --git a/drivers/net/ethernet/intel/igc/igc_ethtool.c b/drivers/net/ethernet/intel/igc/igc_ethtool.c
index c5be8b936963..3cdb88a5eb01 100644
--- a/drivers/net/ethernet/intel/igc/igc_ethtool.c
+++ b/drivers/net/ethernet/intel/igc/igc_ethtool.c
@@ -1183,46 +1183,6 @@ static int igc_set_rss_hash_opt(struct igc_adapter *adapter,
 	return 0;
 }
 
-static int igc_rxnfc_write_etype_filter(struct igc_adapter *adapter,
-					struct igc_nfc_filter *input)
-{
-	struct igc_hw *hw = &adapter->hw;
-	u8 i;
-	u32 etqf;
-	u16 etype;
-
-	/* find an empty etype filter register */
-	for (i = 0; i < MAX_ETYPE_FILTER; ++i) {
-		if (!adapter->etype_bitmap[i])
-			break;
-	}
-	if (i == MAX_ETYPE_FILTER) {
-		netdev_err(adapter->netdev,
-			   "ethtool -N: etype filters are all used\n");
-		return -EINVAL;
-	}
-
-	adapter->etype_bitmap[i] = true;
-
-	etqf = rd32(IGC_ETQF(i));
-	etype = ntohs(input->filter.etype & ETHER_TYPE_FULL_MASK);
-
-	etqf |= IGC_ETQF_FILTER_ENABLE;
-	etqf &= ~IGC_ETQF_ETYPE_MASK;
-	etqf |= (etype & IGC_ETQF_ETYPE_MASK);
-
-	etqf &= ~IGC_ETQF_QUEUE_MASK;
-	etqf |= ((input->action << IGC_ETQF_QUEUE_SHIFT)
-		& IGC_ETQF_QUEUE_MASK);
-	etqf |= IGC_ETQF_QUEUE_ENABLE;
-
-	wr32(IGC_ETQF(i), etqf);
-
-	input->etype_reg_index = i;
-
-	return 0;
-}
-
 int igc_add_filter(struct igc_adapter *adapter, struct igc_nfc_filter *input)
 {
 	struct igc_hw *hw = &adapter->hw;
@@ -1236,7 +1196,9 @@ int igc_add_filter(struct igc_adapter *adapter, struct igc_nfc_filter *input)
 	}
 
 	if (input->filter.match_flags & IGC_FILTER_FLAG_ETHER_TYPE) {
-		err = igc_rxnfc_write_etype_filter(adapter, input);
+		u16 etype = ntohs(input->filter.etype);
+
+		err = igc_add_etype_filter(adapter, etype, input->action);
 		if (err)
 			return err;
 	}
@@ -1267,26 +1229,13 @@ int igc_add_filter(struct igc_adapter *adapter, struct igc_nfc_filter *input)
 	return 0;
 }
 
-static void igc_clear_etype_filter_regs(struct igc_adapter *adapter,
-					u16 reg_index)
-{
-	struct igc_hw *hw = &adapter->hw;
-	u32 etqf = rd32(IGC_ETQF(reg_index));
-
-	etqf &= ~IGC_ETQF_QUEUE_ENABLE;
-	etqf &= ~IGC_ETQF_QUEUE_MASK;
-	etqf &= ~IGC_ETQF_FILTER_ENABLE;
-
-	wr32(IGC_ETQF(reg_index), etqf);
-
-	adapter->etype_bitmap[reg_index] = false;
-}
-
 int igc_erase_filter(struct igc_adapter *adapter, struct igc_nfc_filter *input)
 {
-	if (input->filter.match_flags & IGC_FILTER_FLAG_ETHER_TYPE)
-		igc_clear_etype_filter_regs(adapter,
-					    input->etype_reg_index);
+	if (input->filter.match_flags & IGC_FILTER_FLAG_ETHER_TYPE) {
+		u16 etype = ntohs(input->filter.etype);
+
+		igc_del_etype_filter(adapter, etype);
+	}
 
 	if (input->filter.match_flags & IGC_FILTER_FLAG_VLAN_TCI) {
 		int prio = (ntohs(input->filter.vlan_tci) & VLAN_PRIO_MASK) >>