udp: add gso support to virtual devices

Virtual devices such as tunnels and bonding can handle large packets.
Only segment packets when reaching a physical or loopback device.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/networking/netdev-features.txt b/Documentation/networking/netdev-features.txt
index c77f9d57eb91584878d26061450c3e08a5b19030..c4a54c162547d3e290a69446afadef54aac7f1d5 100644 (file)
--- a/Documentation/networking/netdev-features.txt
+++ b/Documentation/networking/netdev-features.txt
@@ -113,6 +113,13 @@ whatever headers there might be.
 NETIF_F_TSO_ECN means that hardware can properly split packets with CWR bit
 set, be it TCPv4 (when NETIF_F_TSO is enabled) or TCPv6 (NETIF_F_TSO6).
 
+ * Transmit UDP segmentation offload
+
+NETIF_F_GSO_UDP_GSO_L4 accepts a single UDP header with a payload that exceeds
+gso_size. On segmentation, it segments the payload on gso_size boundaries and
+replicates the network and UDP headers (fixing up the last one if less than
+gso_size).
+
  * Transmit DMA from high memory
 
 On platforms where this is relevant, NETIF_F_HIGHDMA signals that

diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index 35b79f47a13de3a6664fe6c8e79e75c4738f2fd7..fe2f3b30960ee381f8c1f598084d1bab76f37f0c 100644 (file)
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -55,8 +55,9 @@ enum {
        NETIF_F_GSO_SCTP_BIT,           /* ... SCTP fragmentation */
        NETIF_F_GSO_ESP_BIT,            /* ... ESP with TSO */
        NETIF_F_GSO_UDP_BIT,            /* ... UFO, deprecated except tuntap */
+       NETIF_F_GSO_UDP_L4_BIT,         /* ... UDP payload GSO (not UFO) */
        /**/NETIF_F_GSO_LAST =          /* last bit, see GSO_MASK */
-               NETIF_F_GSO_UDP_BIT,
+               NETIF_F_GSO_UDP_L4_BIT,
 
        NETIF_F_FCOE_CRC_BIT,           /* FCoE CRC32 */
        NETIF_F_SCTP_CRC_BIT,           /* SCTP checksum offload */
@@ -147,6 +148,7 @@ enum {
 #define NETIF_F_HW_ESP_TX_CSUM __NETIF_F(HW_ESP_TX_CSUM)
 #define        NETIF_F_RX_UDP_TUNNEL_PORT  __NETIF_F(RX_UDP_TUNNEL_PORT)
 #define NETIF_F_HW_TLS_RECORD  __NETIF_F(HW_TLS_RECORD)
+#define NETIF_F_GSO_UDP_L4     __NETIF_F(GSO_UDP_L4)
 
 #define for_each_netdev_feature(mask_addr, bit)        \
        for_each_set_bit(bit, (unsigned long *)mask_addr, NETDEV_FEATURE_COUNT)
@@ -216,6 +218,7 @@ enum {
                                 NETIF_F_GSO_GRE_CSUM |                 \
                                 NETIF_F_GSO_IPXIP4 |                   \
                                 NETIF_F_GSO_IPXIP6 |                   \
+                                NETIF_F_GSO_UDP_L4 |                   \
                                 NETIF_F_GSO_UDP_TUNNEL |               \
                                 NETIF_F_GSO_UDP_TUNNEL_CSUM)
 

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 14e0777ffcfb0b2a501fe5ae5a1a70f5f8666d24..366c32891158dd1f27135b369835d3fcb165c22b 100644 (file)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4186,6 +4186,7 @@ static inline bool net_gso_ok(netdev_features_t features, int gso_type)
        BUILD_BUG_ON(SKB_GSO_SCTP    != (NETIF_F_GSO_SCTP >> NETIF_F_GSO_SHIFT));
        BUILD_BUG_ON(SKB_GSO_ESP != (NETIF_F_GSO_ESP >> NETIF_F_GSO_SHIFT));
        BUILD_BUG_ON(SKB_GSO_UDP != (NETIF_F_GSO_UDP >> NETIF_F_GSO_SHIFT));
+       BUILD_BUG_ON(SKB_GSO_UDP_L4 != (NETIF_F_GSO_UDP_L4 >> NETIF_F_GSO_SHIFT));
 
        return (features & feature) == feature;
 }

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 03416e6dd5d7b0c2bb4dbfc805832e4fb67fba92..4650fd6d678cebb5b41e2d3034ad0fd14dc3f073 100644 (file)
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -92,6 +92,7 @@ static const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN]
        [NETIF_F_GSO_PARTIAL_BIT] =      "tx-gso-partial",
        [NETIF_F_GSO_SCTP_BIT] =         "tx-sctp-segmentation",
        [NETIF_F_GSO_ESP_BIT] =          "tx-esp-segmentation",
+       [NETIF_F_GSO_UDP_L4_BIT] =       "tx-udp-segmentation",
 
        [NETIF_F_FCOE_CRC_BIT] =         "tx-checksum-fcoe-crc",
        [NETIF_F_SCTP_CRC_BIT] =        "tx-checksum-sctp",