[PATCH net v4] net: stmmac: remove software VLAN tag stripping

[he.peilin]

The software VLAN stripping logic in stmmac_rx_vlan() was originally
introduced in 2014 by commit b93819854d6e ("stmmac: Add vlan rx for
better GRO performance.") as a workaround to improve GRO performance,
since at that time GRO could not handle frames with VLAN tags. However,
this limitation was resolved in 2015 by commit 66e5133f19e9 ("vlan: Add
GRO support for non hardware accelerated vlan"), which added GRO support
for non-hardware-accelerated VLAN frames. Keeping a software fallback
path for VLAN stripping is no longer necessary and only adds complexity.

Fixes: b93819854d6e ("stmmac: Add vlan rx for better GRO performance.")
Signed-off-by: Peilin He <he.peilin@xxxxxxxxxx>
Reviewed-by: xu xin <xu.xin16@xxxxxxxxxx>
Reviewed-by: Jiang Kun <jiang.kun2@xxxxxxxxxx>
---
../net/ethernet/stmicro/stmmac/stmmac_main.c | 28 ++-----------------
1 file changed, 2 insertions(+), 26 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index b2b7d0242dd3..2e3b0cf10d66 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -5021,24 +5021,6 @@ static netdev_features_t stmmac_features_check(struct sk_buff *skb,
return vlan_features_check(skb, features);
}

-static void stmmac_rx_vlan(struct net_device *dev, struct sk_buff *skb)
-{
- struct vlan_ethhdr *veth = skb_vlan_eth_hdr(skb);
- __be16 vlan_proto = veth->h_vlan_proto;
- u16 vlanid;
-
- if ((vlan_proto == htons(ETH_P_8021Q) &&
- dev->features & NETIF_F_HW_VLAN_CTAG_RX) ||
- (vlan_proto == htons(ETH_P_8021AD) &&
- dev->features & NETIF_F_HW_VLAN_STAG_RX)) {
- /* pop the vlan tag */
- vlanid = ntohs(veth->h_vlan_TCI);
- memmove(skb->data + VLAN_HLEN, veth, ETH_ALEN * 2);
- skb_pull(skb, VLAN_HLEN);
- __vlan_hwaccel_put_tag(skb, vlan_proto, vlanid);
- }
-}
-
/**
* stmmac_rx_refill - refill used skb preallocated buffers
* @priv: driver private structure
@@ -5407,9 +5389,7 @@ static void stmmac_dispatch_skb_zc(struct stmmac_priv *priv, u32 queue,
if (priv->hw->hw_vlan_en)
/* MAC level stripping. */
stmmac_rx_hw_vlan(priv, priv->hw, p, skb);
- else
- /* Driver level stripping. */
- stmmac_rx_vlan(priv->dev, skb);
+
skb->protocol = eth_type_trans(skb, priv->dev);

if (unlikely(!coe) || !stmmac_has_ip_ethertype(skb))
@@ -5901,9 +5881,6 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
if (priv->hw->hw_vlan_en)
/* MAC level stripping. */
stmmac_rx_hw_vlan(priv, priv->hw, p, skb);
- else
- /* Driver level stripping. */
- stmmac_rx_vlan(priv->dev, skb);

skb->protocol = eth_type_trans(skb, priv->dev);

@@ -7964,9 +7941,8 @@ static int __stmmac_dvr_probe(struct device *device,
ndev->features |= ndev->hw_features | NETIF_F_HIGHDMA;
ndev->watchdog_timeo = msecs_to_jiffies(watchdog);
#ifdef STMMAC_VLAN_TAG_USED
- /* Both mac100 and gmac support receive VLAN tag detection */
- ndev->features |= NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_HW_VLAN_STAG_RX;
if (dwmac_is_xmac(priv->plat->core_type)) {
+ ndev->features |= NETIF_F_HW_VLAN_CTAG_RX;
ndev->hw_features |= NETIF_F_HW_VLAN_CTAG_RX;
priv->hw->hw_vlan_en = true;
}
--
2.27.0