net: introduce a netdev feature for UDP GRO forwarding

Introduce a new netdev feature, NETIF_F_GRO_UDP_FWD, to allow user
to turn UDP GRO on and off for forwarding.
Defaults to off to not change current datapath.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index 934de56..c06d6aa 100644 (file)
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -84,6 +84,7 @@ enum {
        NETIF_F_GRO_FRAGLIST_BIT,       /* Fraglist GRO */
 
        NETIF_F_HW_MACSEC_BIT,          /* Offload MACsec operations */
+       NETIF_F_GRO_UDP_FWD_BIT,        /* Allow UDP GRO for forwarding */
 
        /*
         * Add your fresh new feature above and remember to update
@@ -157,6 +158,7 @@ enum {
 #define NETIF_F_GRO_FRAGLIST   __NETIF_F(GRO_FRAGLIST)
 #define NETIF_F_GSO_FRAGLIST   __NETIF_F(GSO_FRAGLIST)
 #define NETIF_F_HW_MACSEC      __NETIF_F(HW_MACSEC)
+#define NETIF_F_GRO_UDP_FWD    __NETIF_F(GRO_UDP_FWD)
 
 /* Finds the next feature with the highest number of the range of start till 0.
  */
@@ -234,7 +236,7 @@ static inline int find_next_netdev_feature(u64 feature, unsigned long start)
 #define NETIF_F_SOFT_FEATURES  (NETIF_F_GSO | NETIF_F_GRO)
 
 /* Changeable features with no special hardware requirements that defaults to off. */
-#define NETIF_F_SOFT_FEATURES_OFF      NETIF_F_GRO_FRAGLIST
+#define NETIF_F_SOFT_FEATURES_OFF      (NETIF_F_GRO_FRAGLIST | NETIF_F_GRO_UDP_FWD)
 
 #define NETIF_F_VLAN_FEATURES  (NETIF_F_HW_VLAN_CTAG_FILTER | \
                                 NETIF_F_HW_VLAN_CTAG_RX | \

diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 24036e3..1812201 100644 (file)
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -68,6 +68,7 @@ const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] = {
        [NETIF_F_HW_TLS_RX_BIT] =        "tls-hw-rx-offload",
        [NETIF_F_GRO_FRAGLIST_BIT] =     "rx-gro-list",
        [NETIF_F_HW_MACSEC_BIT] =        "macsec-hw-offload",
+       [NETIF_F_GRO_UDP_FWD_BIT] =      "rx-udp-gro-forwarding",
 };
 
 const char