[PATCH net] net: airoha: Keep UPDMEM egress MAC in sync for offloaded IPv6 flows

[陈耀明]

Ooo,  the new patch should be a dedicated leaf lock inside
airoha_ppe_init_upd_mem().
--- a/drivers/net/ethernet/airoha/airoha_ppe.c
+++ b/drivers/net/ethernet/airoha/airoha_ppe.c
@@ -416,6 +416,19 @@
   dsa_port);

  smac_id = port->id;
+ /*
+ * Routed IPv6 entries resolve the egress source MAC
+ * through the UPDMEM table indexed by smac_id. The
+ * egress netdev can legally carry a different address
+ * than the GDM port itself: on PON setups the
+ * authentication MAC lives on the pon device while
+ * each service VLAN routes with its own address. Keep
+ * the table entry in sync with the source address this
+ * flow is actually going to use.
+ */
+ if (type >= PPE_PKT_TYPE_IPV6_ROUTE_3T)
+ airoha_ppe_init_upd_mem(dev,
+ data->eth.h_source);
  }
  }

@@ -1529,10 +1542,21 @@

 void airoha_ppe_init_upd_mem(struct airoha_gdm_dev *dev, const u8 *addr)
 {
+ static DEFINE_MUTEX(updmem_lock);
+
  struct airoha_gdm_port *port = dev->port;
  struct airoha_eth *eth = dev->eth;
  u32 val;

+ /*
+ * Routed IPv6 entries resolve the egress source MAC through the
+ * UPDMEM table indexed by smac_id; the ndo_open/ndo_set_mac_address
+ * writers hold flow_offload_mutex (QoS paths re-lock via
+ * airoha_set_macaddr()), so this lock also serializes the leaf
+ * against them.
+ */
+ mutex_lock(&updmem_lock);
+
  val = (addr[2] << 24) | (addr[3] << 16) | (addr[4] << 8) | addr[5];
  airoha_fe_wr(eth, REG_UPDMEM_DATA(0), val);
  airoha_fe_wr(eth, REG_UPDMEM_CTRL(0),
@@ -1545,6 +1569,8 @@
      FIELD_PREP(PPE_UPDMEM_ADDR_MASK, port->id) |
      FIELD_PREP(PPE_UPDMEM_OFFSET_MASK, 1) |
      PPE_UPDMEM_WR_MASK | PPE_UPDMEM_REQ_MASK);
+
+ mutex_unlock(&updmem_lock);
 }

 struct airoha_ppe_dev *airoha_ppe_get_dev(struct device *dev)