mediatek: add kernel code for supporting offloading wlan->eth and wlan->wlan flows

Will be enabled by an upcoming mt76 update

Signed-off-by: Felix Fietkau <nbd@nbd.name>

1 files changed, 37 insertions, 0 deletions

diff --git a/target/linux/generic/pending-5.15/736-02-net-ethernet-mediatek-mtk_ppe-prefer-newly-added-l2-.patch b/target/linux/generic/pending-5.15/736-02-net-ethernet-mediatek-mtk_ppe-prefer-newly-added-l2-.patch
new file mode 100644
index 0000000000..6e17e4dc52
--- /dev/null
+++ b/target/linux/generic/pending-5.15/736-02-net-ethernet-mediatek-mtk_ppe-prefer-newly-added-l2-.patch
@@ -0,0 +1,37 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Mon, 20 Mar 2023 15:37:55 +0100
+Subject: [PATCH] net: ethernet: mediatek: mtk_ppe: prefer newly added l2
+ flows over existing ones
+
+When a device is roaming between interfaces and a new flow entry is created,
+we should assume that its output device is more up to date than whatever
+entry existed already.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/drivers/net/ethernet/mediatek/mtk_ppe.c
++++ b/drivers/net/ethernet/mediatek/mtk_ppe.c
+@@ -639,10 +639,20 @@ void mtk_foe_entry_clear(struct mtk_ppe
+ static int
+ mtk_foe_entry_commit_l2(struct mtk_ppe *ppe, struct mtk_flow_entry *entry)
+ {
++	struct mtk_flow_entry *prev;
++
+ 	entry->type = MTK_FLOW_TYPE_L2;
+ 
+-	return rhashtable_insert_fast(&ppe->l2_flows, &entry->l2_node,
+-				      mtk_flow_l2_ht_params);
++	prev = rhashtable_lookup_get_insert_fast(&ppe->l2_flows, &entry->l2_node,
++						 mtk_flow_l2_ht_params);
++	if (likely(!prev))
++		return 0;
++
++	if (IS_ERR(prev))
++		return PTR_ERR(prev);
++
++	return rhashtable_replace_fast(&ppe->l2_flows, &prev->l2_node,
++				       &entry->l2_node, mtk_flow_l2_ht_params);
+ }
+ 
+ int mtk_foe_entry_commit(struct mtk_ppe *ppe, struct mtk_flow_entry *entry)