From 55dc5a9f2f2afd32d7b1bda44a5fc95e67a3371f Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:40 -0800 Subject: [PATCH 1/8] net: Add skb_inner_transport_offset function Same thing as skb_transport_offset but returns the offset of the inner transport header (when skb->encpasulation is set). Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/linux/skbuff.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index af4f6ac025b6..2393373c9d08 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1939,6 +1939,11 @@ static inline unsigned char *skb_inner_transport_header(const struct sk_buff return skb->head + skb->inner_transport_header; } +static inline int skb_inner_transport_offset(const struct sk_buff *skb) +{ + return skb_inner_transport_header(skb) - skb->data; +} + static inline void skb_reset_inner_transport_header(struct sk_buff *skb) { skb->inner_transport_header = skb->data - skb->head; From 53692b1de419c1b59106909c7f6b4dd3dbc768ac Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:41 -0800 Subject: [PATCH 2/8] sctp: Rename NETIF_F_SCTP_CSUM to NETIF_F_SCTP_CRC The SCTP checksum is really a CRC and is very different from the standards 1's complement checksum that serves as the checksum for IP protocols. This offload interface is also very different. Rename NETIF_F_SCTP_CSUM to NETIF_F_SCTP_CRC to highlight these differences. The term CSUM should be reserved in the stack to refer to the standard 1's complement IP checksum. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- drivers/net/ethernet/intel/i40e/i40e_main.c | 2 +- drivers/net/ethernet/intel/i40evf/i40evf_main.c | 2 +- drivers/net/ethernet/intel/igb/igb_main.c | 4 ++-- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 4 ++-- drivers/net/loopback.c | 2 +- include/linux/netdev_features.h | 4 ++-- net/8021q/vlan_dev.c | 2 +- net/core/ethtool.c | 4 ++-- net/netfilter/ipvs/ip_vs_proto_sctp.c | 2 +- net/sctp/output.c | 2 +- 10 files changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index b118deb08ce6..a63d980f478e 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -8842,7 +8842,7 @@ static int i40e_config_netdev(struct i40e_vsi *vsi) netdev->features = NETIF_F_SG | NETIF_F_IP_CSUM | - NETIF_F_SCTP_CSUM | + NETIF_F_SCTP_CRC | NETIF_F_HIGHDMA | NETIF_F_GSO_UDP_TUNNEL | NETIF_F_GSO_GRE | diff --git a/drivers/net/ethernet/intel/i40evf/i40evf_main.c b/drivers/net/ethernet/intel/i40evf/i40evf_main.c index 455394cf7f80..4d05ff6f0423 100644 --- a/drivers/net/ethernet/intel/i40evf/i40evf_main.c +++ b/drivers/net/ethernet/intel/i40evf/i40evf_main.c @@ -2321,7 +2321,7 @@ int i40evf_process_config(struct i40evf_adapter *adapter) netdev->features |= NETIF_F_HIGHDMA | NETIF_F_SG | NETIF_F_IP_CSUM | - NETIF_F_SCTP_CSUM | + NETIF_F_SCTP_CRC | NETIF_F_IPV6_CSUM | NETIF_F_TSO | NETIF_F_TSO6 | diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 7afde455326d..31e5f3942839 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -2379,8 +2379,8 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) } if (hw->mac.type >= e1000_82576) { - netdev->hw_features |= NETIF_F_SCTP_CSUM; - netdev->features |= NETIF_F_SCTP_CSUM; + netdev->hw_features |= NETIF_F_SCTP_CRC; + netdev->features |= NETIF_F_SCTP_CRC; } netdev->priv_flags |= IFF_UNICAST_FLT; diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 66c64a376719..9f27001cac1f 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -8995,8 +8995,8 @@ skip_sriov: case ixgbe_mac_X540: case ixgbe_mac_X550: case ixgbe_mac_X550EM_x: - netdev->features |= NETIF_F_SCTP_CSUM; - netdev->hw_features |= NETIF_F_SCTP_CSUM | + netdev->features |= NETIF_F_SCTP_CRC; + netdev->hw_features |= NETIF_F_SCTP_CRC | NETIF_F_NTUPLE; break; default: diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index dc7d970bd1c0..a400288cb37b 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -175,7 +175,7 @@ static void loopback_setup(struct net_device *dev) | NETIF_F_UFO | NETIF_F_HW_CSUM | NETIF_F_RXCSUM - | NETIF_F_SCTP_CSUM + | NETIF_F_SCTP_CRC | NETIF_F_HIGHDMA | NETIF_F_LLTX | NETIF_F_NETNS_LOCAL diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h index f0d87347df19..6395f8309393 100644 --- a/include/linux/netdev_features.h +++ b/include/linux/netdev_features.h @@ -52,7 +52,7 @@ enum { NETIF_F_GSO_TUNNEL_REMCSUM_BIT, NETIF_F_FCOE_CRC_BIT, /* FCoE CRC32 */ - NETIF_F_SCTP_CSUM_BIT, /* SCTP checksum offload */ + NETIF_F_SCTP_CRC_BIT, /* SCTP checksum offload */ NETIF_F_FCOE_MTU_BIT, /* Supports max FCoE MTU, 2158 bytes*/ NETIF_F_NTUPLE_BIT, /* N-tuple filters supported */ NETIF_F_RXHASH_BIT, /* Receive hashing offload */ @@ -103,7 +103,7 @@ enum { #define NETIF_F_NTUPLE __NETIF_F(NTUPLE) #define NETIF_F_RXCSUM __NETIF_F(RXCSUM) #define NETIF_F_RXHASH __NETIF_F(RXHASH) -#define NETIF_F_SCTP_CSUM __NETIF_F(SCTP_CSUM) +#define NETIF_F_SCTP_CRC __NETIF_F(SCTP_CRC) #define NETIF_F_SG __NETIF_F(SG) #define NETIF_F_TSO6 __NETIF_F(TSO6) #define NETIF_F_TSO_ECN __NETIF_F(TSO_ECN) diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c index 9f4bd137e045..45b74e875381 100644 --- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -545,7 +545,7 @@ static int vlan_dev_init(struct net_device *dev) dev->hw_features = NETIF_F_ALL_CSUM | NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_GSO_SOFTWARE | - NETIF_F_HIGHDMA | NETIF_F_SCTP_CSUM | + NETIF_F_HIGHDMA | NETIF_F_SCTP_CRC | NETIF_F_ALL_FCOE; dev->features |= real_dev->vlan_features | NETIF_F_LLTX | diff --git a/net/core/ethtool.c b/net/core/ethtool.c index 29edf74846fc..4a0cab85d67d 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -87,7 +87,7 @@ static const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] [NETIF_F_GSO_UDP_TUNNEL_BIT] = "tx-udp_tnl-segmentation", [NETIF_F_FCOE_CRC_BIT] = "tx-checksum-fcoe-crc", - [NETIF_F_SCTP_CSUM_BIT] = "tx-checksum-sctp", + [NETIF_F_SCTP_CRC_BIT] = "tx-checksum-sctp", [NETIF_F_FCOE_MTU_BIT] = "fcoe-mtu", [NETIF_F_NTUPLE_BIT] = "rx-ntuple-filter", [NETIF_F_RXHASH_BIT] = "rx-hashing", @@ -235,7 +235,7 @@ static netdev_features_t ethtool_get_feature_mask(u32 eth_cmd) switch (eth_cmd) { case ETHTOOL_GTXCSUM: case ETHTOOL_STXCSUM: - return NETIF_F_ALL_CSUM | NETIF_F_SCTP_CSUM; + return NETIF_F_ALL_CSUM | NETIF_F_SCTP_CRC; case ETHTOOL_GRXCSUM: case ETHTOOL_SRXCSUM: return NETIF_F_RXCSUM; diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c index 010ddeec135f..d952d67f904d 100644 --- a/net/netfilter/ipvs/ip_vs_proto_sctp.c +++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c @@ -169,7 +169,7 @@ sctp_dnat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp, /* Only update csum if we really have to */ if (sctph->dest != cp->dport || payload_csum || (skb->ip_summed == CHECKSUM_PARTIAL && - !(skb_dst(skb)->dev->features & NETIF_F_SCTP_CSUM))) { + !(skb_dst(skb)->dev->features & NETIF_F_SCTP_CRC))) { sctph->dest = cp->dport; sctp_nat_csum(skb, sctph, sctphoff); } else if (skb->ip_summed != CHECKSUM_PARTIAL) { diff --git a/net/sctp/output.c b/net/sctp/output.c index abe7c2db2412..9d610eddd19e 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -534,7 +534,7 @@ int sctp_packet_transmit(struct sctp_packet *packet) * by CRC32-C as described in . */ if (!sctp_checksum_disable) { - if (!(dst->dev->features & NETIF_F_SCTP_CSUM) || + if (!(dst->dev->features & NETIF_F_SCTP_CRC) || (dst_xfrm(dst) != NULL) || packet->ipfragok) { sh->checksum = sctp_compute_cksum(nskb, 0); } else { From 253aab0597d9e16014888639f801ff89df6949c3 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:42 -0800 Subject: [PATCH 3/8] fcoe: Use CHECKSUM_PARTIAL to indicate CRC offload When setting up CRC offload set ip_summed to CHECKSUM_PARTIAL instead of CHECKSUM_UNNECESSARY. This is consistent with the definition of CHECKSUM_PARTIAL. The only driver that seems to be advertising NETIF_F_FCOE_CRC is ixgbe. AFICT the driver does not look at ip_summed for FCOE and just assumes that CRC is being offloaded. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- drivers/scsi/fcoe/fcoe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c index f4424063b860..0efe7112fc1f 100644 --- a/drivers/scsi/fcoe/fcoe.c +++ b/drivers/scsi/fcoe/fcoe.c @@ -1625,7 +1625,7 @@ static int fcoe_xmit(struct fc_lport *lport, struct fc_frame *fp) /* crc offload */ if (likely(lport->crc_offload)) { - skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_headroom(skb); skb->csum_offset = skb->len; crc = 0; From a188222b6ed29404ac2d4232d35d1fe0e77af370 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:43 -0800 Subject: [PATCH 4/8] net: Rename NETIF_F_ALL_CSUM to NETIF_F_CSUM_MASK The name NETIF_F_ALL_CSUM is a misnomer. This does not correspond to the set of features for offloading all checksums. This is a mask of the checksum offload related features bits. It is incorrect to set both NETIF_F_HW_CSUM and NETIF_F_IP_CSUM or NETIF_F_IPV6 at the same time for features of a device. This patch: - Changes instances of NETIF_F_ALL_CSUM to NETIF_F_CSUM_MASK (where NETIF_F_ALL_CSUM is being used as a mask). - Changes bonding, sfc/efx, ipvlan, macvlan, vlan, and team drivers to use NEITF_F_HW_CSUM in features list instead of NETIF_F_ALL_CSUM. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 7 +++---- drivers/net/ethernet/emulex/benet/be_main.c | 2 +- drivers/net/ethernet/ibm/ibmveth.c | 5 +++-- drivers/net/ethernet/intel/fm10k/fm10k_netdev.c | 2 +- drivers/net/ethernet/intel/i40e/i40e_main.c | 2 +- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +- drivers/net/ethernet/jme.c | 2 +- drivers/net/ethernet/marvell/sky2.c | 2 +- drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 4 ++-- drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_param.c | 2 +- drivers/net/ethernet/sfc/efx.c | 2 +- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++-- drivers/net/ipvlan/ipvlan_main.c | 2 +- drivers/net/macvlan.c | 2 +- drivers/net/macvtap.c | 2 +- drivers/net/team/team.c | 3 +-- drivers/net/usb/r8152.c | 2 +- .../staging/lustre/lnet/klnds/socklnd/socklnd_lib.c | 2 +- include/linux/netdev_features.h | 7 ++++++- include/linux/netdevice.h | 6 +++--- include/net/vxlan.h | 2 +- net/8021q/vlan_dev.c | 2 +- net/core/dev.c | 10 +++++----- net/core/ethtool.c | 2 +- net/ipv4/tcp.c | 4 ++-- 25 files changed, 43 insertions(+), 39 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index fe0e7a6f4d72..cab99fd44c8e 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1067,12 +1067,12 @@ static netdev_features_t bond_fix_features(struct net_device *dev, return features; } -#define BOND_VLAN_FEATURES (NETIF_F_ALL_CSUM | NETIF_F_SG | \ +#define BOND_VLAN_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | \ NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \ NETIF_F_HIGHDMA | NETIF_F_LRO) -#define BOND_ENC_FEATURES (NETIF_F_ALL_CSUM | NETIF_F_SG | NETIF_F_RXCSUM |\ - NETIF_F_ALL_TSO) +#define BOND_ENC_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | \ + NETIF_F_RXCSUM | NETIF_F_ALL_TSO) static void bond_compute_features(struct bonding *bond) { @@ -4182,7 +4182,6 @@ void bond_setup(struct net_device *bond_dev) NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_HW_VLAN_CTAG_FILTER; - bond_dev->hw_features &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_HW_CSUM); bond_dev->hw_features |= NETIF_F_GSO_ENCAP_ALL; bond_dev->features |= bond_dev->hw_features; } diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c index 4cab8879f5ae..34e324f20d80 100644 --- a/drivers/net/ethernet/emulex/benet/be_main.c +++ b/drivers/net/ethernet/emulex/benet/be_main.c @@ -5289,7 +5289,7 @@ static netdev_features_t be_features_check(struct sk_buff *skb, skb->inner_protocol != htons(ETH_P_TEB) || skb_inner_mac_header(skb) - skb_transport_header(skb) != sizeof(struct udphdr) + sizeof(struct vxlanhdr)) - return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK); + return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); return features; } diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c index 7af870a3c549..6691b5a45b9d 100644 --- a/drivers/net/ethernet/ibm/ibmveth.c +++ b/drivers/net/ethernet/ibm/ibmveth.c @@ -763,7 +763,7 @@ static netdev_features_t ibmveth_fix_features(struct net_device *dev, */ if (!(features & NETIF_F_RXCSUM)) - features &= ~NETIF_F_ALL_CSUM; + features &= ~NETIF_F_CSUM_MASK; return features; } @@ -928,7 +928,8 @@ static int ibmveth_set_features(struct net_device *dev, rc1 = ibmveth_set_csum_offload(dev, rx_csum); if (rc1 && !adapter->rx_csum) dev->features = - features & ~(NETIF_F_ALL_CSUM | NETIF_F_RXCSUM); + features & ~(NETIF_F_CSUM_MASK | + NETIF_F_RXCSUM); } if (large_send != adapter->large_send) { diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_netdev.c b/drivers/net/ethernet/intel/fm10k/fm10k_netdev.c index d9854d39576d..83ddf362ea77 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_netdev.c +++ b/drivers/net/ethernet/intel/fm10k/fm10k_netdev.c @@ -1357,7 +1357,7 @@ static netdev_features_t fm10k_features_check(struct sk_buff *skb, if (!skb->encapsulation || fm10k_tx_encap_offload(skb)) return features; - return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK); + return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); } static const struct net_device_ops fm10k_netdev_ops = { diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index a63d980f478e..c284e4341c7c 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -8766,7 +8766,7 @@ static netdev_features_t i40e_features_check(struct sk_buff *skb, if (skb->encapsulation && (skb_inner_mac_header(skb) - skb_transport_header(skb) > I40E_MAX_TUNNEL_HDR_LEN)) - return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK); + return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); return features; } diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 9f27001cac1f..fca35aa90d0f 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -8598,7 +8598,7 @@ ixgbe_features_check(struct sk_buff *skb, struct net_device *dev, if (unlikely(skb_inner_mac_header(skb) - skb_transport_header(skb) > IXGBE_MAX_TUNNEL_HDR_LEN)) - return features & ~NETIF_F_ALL_CSUM; + return features & ~NETIF_F_CSUM_MASK; return features; } diff --git a/drivers/net/ethernet/jme.c b/drivers/net/ethernet/jme.c index 060dd3922974..b1de7afd4116 100644 --- a/drivers/net/ethernet/jme.c +++ b/drivers/net/ethernet/jme.c @@ -2753,7 +2753,7 @@ static netdev_features_t jme_fix_features(struct net_device *netdev, netdev_features_t features) { if (netdev->mtu > 1900) - features &= ~(NETIF_F_ALL_TSO | NETIF_F_ALL_CSUM); + features &= ~(NETIF_F_ALL_TSO | NETIF_F_CSUM_MASK); return features; } diff --git a/drivers/net/ethernet/marvell/sky2.c b/drivers/net/ethernet/marvell/sky2.c index 5606a043063e..ec0a22119e09 100644 --- a/drivers/net/ethernet/marvell/sky2.c +++ b/drivers/net/ethernet/marvell/sky2.c @@ -4380,7 +4380,7 @@ static netdev_features_t sky2_fix_features(struct net_device *dev, */ if (dev->mtu > ETH_DATA_LEN && hw->chip_id == CHIP_ID_YUKON_EC_U) { netdev_info(dev, "checksum offload not possible with jumbo frames\n"); - features &= ~(NETIF_F_TSO|NETIF_F_SG|NETIF_F_ALL_CSUM); + features &= ~(NETIF_F_TSO | NETIF_F_SG | NETIF_F_CSUM_MASK); } /* Some hardware requires receive checksum for RSS to work. */ diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c index 038ac6b14a60..7060539d276a 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c @@ -2071,7 +2071,7 @@ nfp_net_features_check(struct sk_buff *skb, struct net_device *dev, l4_hdr = ipv6_hdr(skb)->nexthdr; break; default: - return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK); + return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); } if (skb->inner_protocol_type != ENCAP_TYPE_ETHER || @@ -2080,7 +2080,7 @@ nfp_net_features_check(struct sk_buff *skb, struct net_device *dev, (l4_hdr == IPPROTO_UDP && (skb_inner_mac_header(skb) - skb_transport_header(skb) != sizeof(struct udphdr) + sizeof(struct vxlanhdr)))) - return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK); + return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); return features; } diff --git a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_param.c b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_param.c index 08d4be616064..e097e6baaac4 100644 --- a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_param.c +++ b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_param.c @@ -500,7 +500,7 @@ void pch_gbe_check_options(struct pch_gbe_adapter *adapter) val = XsumTX; pch_gbe_validate_option(&val, &opt, adapter); if (!val) - dev->features &= ~NETIF_F_ALL_CSUM; + dev->features &= ~NETIF_F_CSUM_MASK; } { /* Flow Control */ static const struct pch_gbe_option opt = { diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index b405349a570c..1fe13c733c1e 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -3131,7 +3131,7 @@ static int efx_pci_probe(struct pci_dev *pci_dev, if (efx->type->offload_features & NETIF_F_V6_CSUM) net_dev->features |= NETIF_F_TSO6; /* Mask for features that also apply to VLAN devices */ - net_dev->vlan_features |= (NETIF_F_ALL_CSUM | NETIF_F_SG | + net_dev->vlan_features |= (NETIF_F_HW_CSUM | NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_ALL_TSO | NETIF_F_RXCSUM); /* All offloads can be toggled */ diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 3c6549aee11d..0b0fea73a7a7 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -2402,7 +2402,7 @@ static netdev_features_t stmmac_fix_features(struct net_device *dev, features &= ~NETIF_F_RXCSUM; if (!priv->plat->tx_coe) - features &= ~NETIF_F_ALL_CSUM; + features &= ~NETIF_F_CSUM_MASK; /* Some GMAC devices have a bugged Jumbo frame support that * needs to have the Tx COE disabled for oversized frames @@ -2410,7 +2410,7 @@ static netdev_features_t stmmac_fix_features(struct net_device *dev, * the TX csum insertionin the TDES and not use SF. */ if (priv->plat->bugged_jumbo && (dev->mtu > ETH_DATA_LEN)) - features &= ~NETIF_F_ALL_CSUM; + features &= ~NETIF_F_CSUM_MASK; return features; } diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c index a9268db4e349..f94392d07126 100644 --- a/drivers/net/ipvlan/ipvlan_main.c +++ b/drivers/net/ipvlan/ipvlan_main.c @@ -88,7 +88,7 @@ static struct lock_class_key ipvlan_netdev_xmit_lock_key; static struct lock_class_key ipvlan_netdev_addr_lock_key; #define IPVLAN_FEATURES \ - (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \ + (NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \ NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \ NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \ NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_STAG_FILTER) diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 06c8bfeaccd6..ae3b486fb663 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -762,7 +762,7 @@ static struct lock_class_key macvlan_netdev_addr_lock_key; NETIF_F_GSO_ROBUST) #define MACVLAN_FEATURES \ - (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \ + (NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \ NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_LRO | \ NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \ NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_STAG_FILTER) diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 0fc521941c71..d636d051fac8 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -388,7 +388,7 @@ static rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb) * check, we either support them all or none. */ if (skb->ip_summed == CHECKSUM_PARTIAL && - !(features & NETIF_F_ALL_CSUM) && + !(features & NETIF_F_CSUM_MASK) && skb_checksum_help(skb)) goto drop; skb_queue_tail(&q->sk.sk_receive_queue, skb); diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index 059c0f60a2b2..915f60fce186 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -981,7 +981,7 @@ static void team_port_disable(struct team *team, team_lower_state_changed(port); } -#define TEAM_VLAN_FEATURES (NETIF_F_ALL_CSUM | NETIF_F_SG | \ +#define TEAM_VLAN_FEATURES (NETIF_F_HW_CSUM | NETIF_F_SG | \ NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \ NETIF_F_HIGHDMA | NETIF_F_LRO) @@ -2091,7 +2091,6 @@ static void team_setup(struct net_device *dev) NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_HW_VLAN_CTAG_FILTER; - dev->hw_features &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_HW_CSUM); dev->features |= dev->hw_features; } diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index d9427ca3dba7..34642a9583e0 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -1986,7 +1986,7 @@ rtl8152_features_check(struct sk_buff *skb, struct net_device *dev, int offset = skb_transport_offset(skb); if ((mss || skb->ip_summed == CHECKSUM_PARTIAL) && offset > max_offset) - features &= ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK); + features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); else if ((skb->len + sizeof(struct tx_desc)) > agg_buf_sz) features &= ~NETIF_F_GSO_MASK; diff --git a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c index 679785b0209c..9de4f23910d8 100644 --- a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c +++ b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c @@ -69,7 +69,7 @@ ksocknal_lib_zc_capable(ksock_conn_t *conn) /* ZC if the socket supports scatter/gather and doesn't need software * checksums */ - return ((caps & NETIF_F_SG) != 0 && (caps & NETIF_F_ALL_CSUM) != 0); + return ((caps & NETIF_F_SG) != 0 && (caps & NETIF_F_CSUM_MASK) != 0); } int diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h index 6395f8309393..2c4e94ab88da 100644 --- a/include/linux/netdev_features.h +++ b/include/linux/netdev_features.h @@ -149,7 +149,12 @@ enum { #define NETIF_F_GEN_CSUM NETIF_F_HW_CSUM #define NETIF_F_V4_CSUM (NETIF_F_GEN_CSUM | NETIF_F_IP_CSUM) #define NETIF_F_V6_CSUM (NETIF_F_GEN_CSUM | NETIF_F_IPV6_CSUM) -#define NETIF_F_ALL_CSUM (NETIF_F_V4_CSUM | NETIF_F_V6_CSUM) + +/* List of IP checksum features. Note that NETIF_HW_CSUM should not be + * set in features when NETIF_F_IP_CSUM or NETIF_F_IPV6_CSUM are set-- + * this would be contradictory + */ +#define NETIF_F_CSUM_MASK (NETIF_F_V4_CSUM | NETIF_F_V6_CSUM) #define NETIF_F_ALL_TSO (NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_TSO_ECN) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 1bb21ff0fa64..a54223a113b1 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3763,12 +3763,12 @@ static inline netdev_features_t netdev_intersect_features(netdev_features_t f1, netdev_features_t f2) { if (f1 & NETIF_F_GEN_CSUM) - f1 |= (NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM); + f1 |= (NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); if (f2 & NETIF_F_GEN_CSUM) - f2 |= (NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM); + f2 |= (NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); f1 &= f2; if (f1 & NETIF_F_GEN_CSUM) - f1 &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM); + f1 &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); return f1; } diff --git a/include/net/vxlan.h b/include/net/vxlan.h index c1c899c3a51b..b5a1aec1a167 100644 --- a/include/net/vxlan.h +++ b/include/net/vxlan.h @@ -232,7 +232,7 @@ static inline netdev_features_t vxlan_features_check(struct sk_buff *skb, skb->inner_protocol != htons(ETH_P_TEB) || (skb_inner_mac_header(skb) - skb_transport_header(skb) != sizeof(struct udphdr) + sizeof(struct vxlanhdr)))) - return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK); + return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); return features; } diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c index 45b74e875381..ad5e2fd1012c 100644 --- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -543,7 +543,7 @@ static int vlan_dev_init(struct net_device *dev) (1<<__LINK_STATE_DORMANT))) | (1<<__LINK_STATE_PRESENT); - dev->hw_features = NETIF_F_ALL_CSUM | NETIF_F_SG | + dev->hw_features = NETIF_F_HW_CSUM | NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_GSO_SOFTWARE | NETIF_F_HIGHDMA | NETIF_F_SCTP_CRC | NETIF_F_ALL_FCOE; diff --git a/net/core/dev.c b/net/core/dev.c index 8f705fcedb94..5a3b5a404642 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2645,7 +2645,7 @@ static netdev_features_t harmonize_features(struct sk_buff *skb, if (skb->ip_summed != CHECKSUM_NONE && !can_checksum_protocol(features, type)) { - features &= ~NETIF_F_ALL_CSUM; + features &= ~NETIF_F_CSUM_MASK; } else if (illegal_highdma(skb->dev, skb)) { features &= ~NETIF_F_SG; } @@ -2792,7 +2792,7 @@ static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device else skb_set_transport_header(skb, skb_checksum_start_offset(skb)); - if (!(features & NETIF_F_ALL_CSUM) && + if (!(features & NETIF_F_CSUM_MASK) && skb_checksum_help(skb)) goto out_kfree_skb; } @@ -7572,15 +7572,15 @@ netdev_features_t netdev_increment_features(netdev_features_t all, netdev_features_t one, netdev_features_t mask) { if (mask & NETIF_F_GEN_CSUM) - mask |= NETIF_F_ALL_CSUM; + mask |= NETIF_F_CSUM_MASK; mask |= NETIF_F_VLAN_CHALLENGED; - all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask; + all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; all &= one | ~NETIF_F_ALL_FOR_ALL; /* If one device supports hw checksumming, set for all. */ if (all & NETIF_F_GEN_CSUM) - all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM); + all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); return all; } diff --git a/net/core/ethtool.c b/net/core/ethtool.c index 4a0cab85d67d..09948a726347 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -235,7 +235,7 @@ static netdev_features_t ethtool_get_feature_mask(u32 eth_cmd) switch (eth_cmd) { case ETHTOOL_GTXCSUM: case ETHTOOL_STXCSUM: - return NETIF_F_ALL_CSUM | NETIF_F_SCTP_CRC; + return NETIF_F_CSUM_MASK | NETIF_F_SCTP_CRC; case ETHTOOL_GRXCSUM: case ETHTOOL_SRXCSUM: return NETIF_F_RXCSUM; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index c82cca18c90f..cf7ef7be79f0 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1018,7 +1018,7 @@ int tcp_sendpage(struct sock *sk, struct page *page, int offset, ssize_t res; if (!(sk->sk_route_caps & NETIF_F_SG) || - !(sk->sk_route_caps & NETIF_F_ALL_CSUM)) + !(sk->sk_route_caps & NETIF_F_CSUM_MASK)) return sock_no_sendpage(sk->sk_socket, page, offset, size, flags); @@ -1175,7 +1175,7 @@ new_segment: /* * Check whether we can use HW checksum. */ - if (sk->sk_route_caps & NETIF_F_ALL_CSUM) + if (sk->sk_route_caps & NETIF_F_CSUM_MASK) skb->ip_summed = CHECKSUM_PARTIAL; skb_entail(sk, skb); From c8cd0989bd151fda87bbf10887b3df18021284bc Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:44 -0800 Subject: [PATCH 5/8] net: Eliminate NETIF_F_GEN_CSUM and NETIF_F_V[46]_CSUM These netif flags are unnecessary convolutions. It is more straightforward to just use NETIF_F_HW_CSUM, NETIF_F_IP_CSUM, and NETIF_F_IPV6_CSUM directly. This patch also: - Cleans up can_checksum_protocol - Simplifies netdev_intersect_features Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- drivers/net/ethernet/sfc/efx.c | 2 +- drivers/net/macvlan.c | 2 +- include/linux/if_vlan.h | 2 +- include/linux/netdev_features.h | 9 ++---- include/linux/netdevice.h | 40 +++++++++++++++--------- net/core/dev.c | 12 +++---- net/core/pktgen.c | 4 +-- net/ipv4/ip_output.c | 2 +- net/ipv4/netfilter/nf_nat_l3proto_ipv4.c | 3 +- net/ipv4/udp.c | 3 +- net/ipv4/udp_offload.c | 5 +-- net/ipv6/ip6_output.c | 2 +- net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 3 +- 13 files changed, 50 insertions(+), 39 deletions(-) diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index 1fe13c733c1e..6f697438545d 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -3128,7 +3128,7 @@ static int efx_pci_probe(struct pci_dev *pci_dev, net_dev->features |= (efx->type->offload_features | NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_TSO | NETIF_F_RXCSUM); - if (efx->type->offload_features & NETIF_F_V6_CSUM) + if (efx->type->offload_features & (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM)) net_dev->features |= NETIF_F_TSO6; /* Mask for features that also apply to VLAN devices */ net_dev->vlan_features |= (NETIF_F_HW_CSUM | NETIF_F_SG | diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index ae3b486fb663..6a57a005e0ca 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -758,7 +758,7 @@ static struct lock_class_key macvlan_netdev_xmit_lock_key; static struct lock_class_key macvlan_netdev_addr_lock_key; #define ALWAYS_ON_FEATURES \ - (NETIF_F_SG | NETIF_F_GEN_CSUM | NETIF_F_GSO_SOFTWARE | NETIF_F_LLTX | \ + (NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_GSO_SOFTWARE | NETIF_F_LLTX | \ NETIF_F_GSO_ROBUST) #define MACVLAN_FEATURES \ diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index 05f5879821b8..a5f6ce6b578c 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -621,7 +621,7 @@ static inline netdev_features_t vlan_features_check(const struct sk_buff *skb, NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | - NETIF_F_GEN_CSUM | + NETIF_F_HW_CSUM | NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX); diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h index 2c4e94ab88da..d9654f0eecb3 100644 --- a/include/linux/netdev_features.h +++ b/include/linux/netdev_features.h @@ -146,15 +146,12 @@ enum { #define NETIF_F_GSO_SOFTWARE (NETIF_F_TSO | NETIF_F_TSO_ECN | \ NETIF_F_TSO6 | NETIF_F_UFO) -#define NETIF_F_GEN_CSUM NETIF_F_HW_CSUM -#define NETIF_F_V4_CSUM (NETIF_F_GEN_CSUM | NETIF_F_IP_CSUM) -#define NETIF_F_V6_CSUM (NETIF_F_GEN_CSUM | NETIF_F_IPV6_CSUM) - -/* List of IP checksum features. Note that NETIF_HW_CSUM should not be +/* List of IP checksum features. Note that NETIF_F_ HW_CSUM should not be * set in features when NETIF_F_IP_CSUM or NETIF_F_IPV6_CSUM are set-- * this would be contradictory */ -#define NETIF_F_CSUM_MASK (NETIF_F_V4_CSUM | NETIF_F_V6_CSUM) +#define NETIF_F_CSUM_MASK (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM | \ + NETIF_F_HW_CSUM) #define NETIF_F_ALL_TSO (NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_TSO_ECN) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index a54223a113b1..283984b67cd9 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3691,13 +3691,24 @@ __be16 skb_network_protocol(struct sk_buff *skb, int *depth); static inline bool can_checksum_protocol(netdev_features_t features, __be16 protocol) { - return ((features & NETIF_F_GEN_CSUM) || - ((features & NETIF_F_V4_CSUM) && - protocol == htons(ETH_P_IP)) || - ((features & NETIF_F_V6_CSUM) && - protocol == htons(ETH_P_IPV6)) || - ((features & NETIF_F_FCOE_CRC) && - protocol == htons(ETH_P_FCOE))); + if (protocol == htons(ETH_P_FCOE)) + return !!(features & NETIF_F_FCOE_CRC); + + /* Assume this is an IP checksum (not SCTP CRC) */ + + if (features & NETIF_F_HW_CSUM) { + /* Can checksum everything */ + return true; + } + + switch (protocol) { + case htons(ETH_P_IP): + return !!(features & NETIF_F_IP_CSUM); + case htons(ETH_P_IPV6): + return !!(features & NETIF_F_IPV6_CSUM); + default: + return false; + } } #ifdef CONFIG_BUG @@ -3762,15 +3773,14 @@ void linkwatch_run_queue(void); static inline netdev_features_t netdev_intersect_features(netdev_features_t f1, netdev_features_t f2) { - if (f1 & NETIF_F_GEN_CSUM) - f1 |= (NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); - if (f2 & NETIF_F_GEN_CSUM) - f2 |= (NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); - f1 &= f2; - if (f1 & NETIF_F_GEN_CSUM) - f1 &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); + if ((f1 ^ f2) & NETIF_F_HW_CSUM) { + if (f1 & NETIF_F_HW_CSUM) + f1 |= (NETIF_F_IP_CSUM|NETIF_F_IP_CSUM); + else + f2 |= (NETIF_F_IP_CSUM|NETIF_F_IP_CSUM); + } - return f1; + return f1 & f2; } static inline netdev_features_t netdev_get_wanted_features( diff --git a/net/core/dev.c b/net/core/dev.c index 5a3b5a404642..45b013f27625 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -6467,9 +6467,9 @@ static netdev_features_t netdev_fix_features(struct net_device *dev, /* UFO needs SG and checksumming */ if (features & NETIF_F_UFO) { /* maybe split UFO into V4 and V6? */ - if (!((features & NETIF_F_GEN_CSUM) || - (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM)) - == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { + if (!(features & NETIF_F_HW_CSUM) && + ((features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) != + (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))) { netdev_dbg(dev, "Dropping NETIF_F_UFO since no checksum offload features.\n"); features &= ~NETIF_F_UFO; @@ -7571,7 +7571,7 @@ static int dev_cpu_callback(struct notifier_block *nfb, netdev_features_t netdev_increment_features(netdev_features_t all, netdev_features_t one, netdev_features_t mask) { - if (mask & NETIF_F_GEN_CSUM) + if (mask & NETIF_F_HW_CSUM) mask |= NETIF_F_CSUM_MASK; mask |= NETIF_F_VLAN_CHALLENGED; @@ -7579,8 +7579,8 @@ netdev_features_t netdev_increment_features(netdev_features_t all, all &= one | ~NETIF_F_ALL_FOR_ALL; /* If one device supports hw checksumming, set for all. */ - if (all & NETIF_F_GEN_CSUM) - all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM); + if (all & NETIF_F_HW_CSUM) + all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); return all; } diff --git a/net/core/pktgen.c b/net/core/pktgen.c index de8d5cc5eb24..2be144498bcf 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -2898,7 +2898,7 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, if (!(pkt_dev->flags & F_UDPCSUM)) { skb->ip_summed = CHECKSUM_NONE; - } else if (odev->features & NETIF_F_V4_CSUM) { + } else if (odev->features & (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM)) { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; udp4_hwcsum(skb, iph->saddr, iph->daddr); @@ -3032,7 +3032,7 @@ static struct sk_buff *fill_packet_ipv6(struct net_device *odev, if (!(pkt_dev->flags & F_UDPCSUM)) { skb->ip_summed = CHECKSUM_NONE; - } else if (odev->features & NETIF_F_V6_CSUM) { + } else if (odev->features & (NETIF_F_HW_CSUM | NETIF_F_IPV6_CSUM)) { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct udphdr, check); diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index e0b94cd843d7..568e2bc0d93d 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -911,7 +911,7 @@ static int __ip_append_data(struct sock *sk, */ if (transhdrlen && length + fragheaderlen <= mtu && - rt->dst.dev->features & NETIF_F_V4_CSUM && + rt->dst.dev->features & (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM) && !(flags & MSG_MORE) && !exthdrlen) csummode = CHECKSUM_PARTIAL; diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c index 5075b7ecd26d..61c7cc22ea68 100644 --- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c +++ b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c @@ -132,7 +132,8 @@ static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb, if (skb->ip_summed != CHECKSUM_PARTIAL) { if (!(rt->rt_flags & RTCF_LOCAL) && - (!skb->dev || skb->dev->features & NETIF_F_V4_CSUM)) { + (!skb->dev || skb->dev->features & + (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM))) { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 0c7b0e61b917..8841e984f8bf 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -772,7 +772,8 @@ void udp_set_csum(bool nocheck, struct sk_buff *skb, else if (skb_is_gso(skb)) uh->check = ~udp_v4_check(len, saddr, daddr, 0); else if (skb_dst(skb) && skb_dst(skb)->dev && - (skb_dst(skb)->dev->features & NETIF_F_V4_CSUM)) { + (skb_dst(skb)->dev->features & + (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM))) { BUG_ON(skb->ip_summed == CHECKSUM_PARTIAL); diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index f9386160cbee..130042660181 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -60,8 +60,9 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, /* Try to offload checksum if possible */ offload_csum = !!(need_csum && - (skb->dev->features & - (is_ipv6 ? NETIF_F_V6_CSUM : NETIF_F_V4_CSUM))); + ((skb->dev->features & NETIF_F_HW_CSUM) || + (skb->dev->features & (is_ipv6 ? + NETIF_F_IPV6_CSUM : NETIF_F_IP_CSUM)))); /* segment inner packet. */ enc_features = skb->dev->hw_enc_features & features; diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index e6a7bd15b9b7..2f748452b4aa 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1322,7 +1322,7 @@ emsgsize: headersize == sizeof(struct ipv6hdr) && length < mtu - headersize && !(flags & MSG_MORE) && - rt->dst.dev->features & NETIF_F_V6_CSUM) + rt->dst.dev->features & (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM)) csummode = CHECKSUM_PARTIAL; if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) { diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c index 238e70c3f7b7..6ce309928841 100644 --- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c +++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c @@ -136,7 +136,8 @@ static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb, if (skb->ip_summed != CHECKSUM_PARTIAL) { if (!(rt->rt6i_flags & RTF_LOCAL) && - (!skb->dev || skb->dev->features & NETIF_F_V6_CSUM)) { + (!skb->dev || skb->dev->features & + (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))) { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) + From 9a49850d0af7b9fd14d091dfe61ef6cb369f86b9 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:45 -0800 Subject: [PATCH 6/8] tcp: Fix conditions to determine checksum offload In tcp_send_sendpage and tcp_sendmsg we check the route capabilities to determine if checksum offload can be performed. This check currently does not take the IP protocol into account for devices that advertise only one of NETIF_F_IPV6_CSUM or NETIF_F_IP_CSUM. This patch adds a function to check capabilities for checksum offload with a socket called sk_check_csum_caps. This function checks for specific IPv4 or IPv6 offload support based on the family of the socket. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/net/sock.h | 9 +++++++++ net/ipv4/tcp.c | 4 ++-- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index 0ca22b014de1..ab0269f4b2cc 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1791,6 +1791,15 @@ static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) sk->sk_route_caps &= ~flags; } +static inline bool sk_check_csum_caps(struct sock *sk) +{ + return (sk->sk_route_caps & NETIF_F_HW_CSUM) || + (sk->sk_family == PF_INET && + (sk->sk_route_caps & NETIF_F_IP_CSUM)) || + (sk->sk_family == PF_INET6 && + (sk->sk_route_caps & NETIF_F_IPV6_CSUM)); +} + static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, struct iov_iter *from, char *to, int copy, int offset) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index cf7ef7be79f0..92b3e61b847d 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1018,7 +1018,7 @@ int tcp_sendpage(struct sock *sk, struct page *page, int offset, ssize_t res; if (!(sk->sk_route_caps & NETIF_F_SG) || - !(sk->sk_route_caps & NETIF_F_CSUM_MASK)) + !sk_check_csum_caps(sk)) return sock_no_sendpage(sk->sk_socket, page, offset, size, flags); @@ -1175,7 +1175,7 @@ new_segment: /* * Check whether we can use HW checksum. */ - if (sk->sk_route_caps & NETIF_F_CSUM_MASK) + if (sk_check_csum_caps(sk)) skb->ip_summed = CHECKSUM_PARTIAL; skb_entail(sk, skb); From 6ae23ad36253a8033c5714c52b691b84456487c5 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:46 -0800 Subject: [PATCH 7/8] net: Add driver helper functions to determine checksum offloadability Add skb_csum_offload_chk driver helper function to determine if a device with limited checksum offload capabilities is able to offload the checksum for a given packet. This patch includes: - The skb_csum_offload_chk function. Returns true if checksum is offloadable, else false. Optionally, in the case that the checksum is not offloable, the function can call skb_checksum_help to resolve the checksum. skb_csum_offload_chk also returns whether the checksum refers to an encapsulated checksum. - Definition of skb_csum_offl_spec structure that caller uses to indicate rules about what it can offload (e.g. IPv4/v6, TCP/UDP only, whether encapsulated checksums can be offloaded, whether checksum with IPv6 extension headers can be offloaded). - Ancilary functions called skb_csum_offload_chk_help, skb_csum_off_chk_help_cmn, skb_csum_off_chk_help_cmn_v4_only. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/linux/netdevice.h | 78 ++++++++++++++++++++++ net/core/dev.c | 136 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 214 insertions(+) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 283984b67cd9..9fb6395967de 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2522,6 +2522,71 @@ static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb, remcsum_unadjust((__sum16 *)ptr, grc->delta); } +struct skb_csum_offl_spec { + __u16 ipv4_okay:1, + ipv6_okay:1, + encap_okay:1, + ip_options_okay:1, + ext_hdrs_okay:1, + tcp_okay:1, + udp_okay:1, + sctp_okay:1, + vlan_okay:1, + no_encapped_ipv6:1, + no_not_encapped:1; +}; + +bool __skb_csum_offload_chk(struct sk_buff *skb, + const struct skb_csum_offl_spec *spec, + bool *csum_encapped, + bool csum_help); + +static inline bool skb_csum_offload_chk(struct sk_buff *skb, + const struct skb_csum_offl_spec *spec, + bool *csum_encapped, + bool csum_help) +{ + if (skb->ip_summed != CHECKSUM_PARTIAL) + return false; + + return __skb_csum_offload_chk(skb, spec, csum_encapped, csum_help); +} + +static inline bool skb_csum_offload_chk_help(struct sk_buff *skb, + const struct skb_csum_offl_spec *spec) +{ + bool csum_encapped; + + return skb_csum_offload_chk(skb, spec, &csum_encapped, true); +} + +static inline bool skb_csum_off_chk_help_cmn(struct sk_buff *skb) +{ + static const struct skb_csum_offl_spec csum_offl_spec = { + .ipv4_okay = 1, + .ip_options_okay = 1, + .ipv6_okay = 1, + .vlan_okay = 1, + .tcp_okay = 1, + .udp_okay = 1, + }; + + return skb_csum_offload_chk_help(skb, &csum_offl_spec); +} + +static inline bool skb_csum_off_chk_help_cmn_v4_only(struct sk_buff *skb) +{ + static const struct skb_csum_offl_spec csum_offl_spec = { + .ipv4_okay = 1, + .ip_options_okay = 1, + .tcp_okay = 1, + .udp_okay = 1, + .vlan_okay = 1, + }; + + return skb_csum_offload_chk_help(skb, &csum_offl_spec); +} + static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, @@ -3711,6 +3776,19 @@ static inline bool can_checksum_protocol(netdev_features_t features, } } +/* Map an ethertype into IP protocol if possible */ +static inline int eproto_to_ipproto(int eproto) +{ + switch (eproto) { + case htons(ETH_P_IP): + return IPPROTO_IP; + case htons(ETH_P_IPV6): + return IPPROTO_IPV6; + default: + return -1; + } +} + #ifdef CONFIG_BUG void netdev_rx_csum_fault(struct net_device *dev); #else diff --git a/net/core/dev.c b/net/core/dev.c index 45b013f27625..914b4a24c654 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -138,6 +138,7 @@ #include #include #include +#include #include "net-sysfs.h" @@ -2471,6 +2472,141 @@ out: } EXPORT_SYMBOL(skb_checksum_help); +/* skb_csum_offload_check - Driver helper function to determine if a device + * with limited checksum offload capabilities is able to offload the checksum + * for a given packet. + * + * Arguments: + * skb - sk_buff for the packet in question + * spec - contains the description of what device can offload + * csum_encapped - returns true if the checksum being offloaded is + * encpasulated. That is it is checksum for the transport header + * in the inner headers. + * checksum_help - when set indicates that helper function should + * call skb_checksum_help if offload checks fail + * + * Returns: + * true: Packet has passed the checksum checks and should be offloadable to + * the device (a driver may still need to check for additional + * restrictions of its device) + * false: Checksum is not offloadable. If checksum_help was set then + * skb_checksum_help was called to resolve checksum for non-GSO + * packets and when IP protocol is not SCTP + */ +bool __skb_csum_offload_chk(struct sk_buff *skb, + const struct skb_csum_offl_spec *spec, + bool *csum_encapped, + bool csum_help) +{ + struct iphdr *iph; + struct ipv6hdr *ipv6; + void *nhdr; + int protocol; + u8 ip_proto; + + if (skb->protocol == htons(ETH_P_8021Q) || + skb->protocol == htons(ETH_P_8021AD)) { + if (!spec->vlan_okay) + goto need_help; + } + + /* We check whether the checksum refers to a transport layer checksum in + * the outermost header or an encapsulated transport layer checksum that + * corresponds to the inner headers of the skb. If the checksum is for + * something else in the packet we need help. + */ + if (skb_checksum_start_offset(skb) == skb_transport_offset(skb)) { + /* Non-encapsulated checksum */ + protocol = eproto_to_ipproto(vlan_get_protocol(skb)); + nhdr = skb_network_header(skb); + *csum_encapped = false; + if (spec->no_not_encapped) + goto need_help; + } else if (skb->encapsulation && spec->encap_okay && + skb_checksum_start_offset(skb) == + skb_inner_transport_offset(skb)) { + /* Encapsulated checksum */ + *csum_encapped = true; + switch (skb->inner_protocol_type) { + case ENCAP_TYPE_ETHER: + protocol = eproto_to_ipproto(skb->inner_protocol); + break; + case ENCAP_TYPE_IPPROTO: + protocol = skb->inner_protocol; + break; + } + nhdr = skb_inner_network_header(skb); + } else { + goto need_help; + } + + switch (protocol) { + case IPPROTO_IP: + if (!spec->ipv4_okay) + goto need_help; + iph = nhdr; + ip_proto = iph->protocol; + if (iph->ihl != 5 && !spec->ip_options_okay) + goto need_help; + break; + case IPPROTO_IPV6: + if (!spec->ipv6_okay) + goto need_help; + if (spec->no_encapped_ipv6 && *csum_encapped) + goto need_help; + ipv6 = nhdr; + nhdr += sizeof(*ipv6); + ip_proto = ipv6->nexthdr; + break; + default: + goto need_help; + } + +ip_proto_again: + switch (ip_proto) { + case IPPROTO_TCP: + if (!spec->tcp_okay || + skb->csum_offset != offsetof(struct tcphdr, check)) + goto need_help; + break; + case IPPROTO_UDP: + if (!spec->udp_okay || + skb->csum_offset != offsetof(struct udphdr, check)) + goto need_help; + break; + case IPPROTO_SCTP: + if (!spec->sctp_okay || + skb->csum_offset != offsetof(struct sctphdr, checksum)) + goto cant_help; + break; + case NEXTHDR_HOP: + case NEXTHDR_ROUTING: + case NEXTHDR_DEST: { + u8 *opthdr = nhdr; + + if (protocol != IPPROTO_IPV6 || !spec->ext_hdrs_okay) + goto need_help; + + ip_proto = opthdr[0]; + nhdr += (opthdr[1] + 1) << 3; + + goto ip_proto_again; + } + default: + goto need_help; + } + + /* Passed the tests for offloading checksum */ + return true; + +need_help: + if (csum_help && !skb_shinfo(skb)->gso_size) + skb_checksum_help(skb); +cant_help: + return false; +} +EXPORT_SYMBOL(__skb_csum_offload_chk); + __be16 skb_network_protocol(struct sk_buff *skb, int *depth) { __be16 type = skb->protocol; From 7a6ae71b2490586ed55105893a18dfc648e5fcbb Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Mon, 14 Dec 2015 11:19:47 -0800 Subject: [PATCH 8/8] net: Elaborate on checksum offload interface description Add specifics and details the description of the interface between the stack and drivers for doing checksum offload. This description is meant to be as specific and complete as possible. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/linux/skbuff.h | 138 ++++++++++++++++++++++++++++++++--------- 1 file changed, 109 insertions(+), 29 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2393373c9d08..6b6bd42d6134 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -39,11 +39,55 @@ #include #include -/* A. Checksumming of received packets by device. +/* The interface for checksum offload between the stack and networking drivers + * is as follows... + * + * A. IP checksum related features + * + * Drivers advertise checksum offload capabilities in the features of a device. + * From the stack's point of view these are capabilities offered by the driver, + * a driver typically only advertises features that it is capable of offloading + * to its device. + * + * The checksum related features are: + * + * NETIF_F_HW_CSUM - The driver (or its device) is able to compute one + * IP (one's complement) checksum for any combination + * of protocols or protocol layering. The checksum is + * computed and set in a packet per the CHECKSUM_PARTIAL + * interface (see below). + * + * NETIF_F_IP_CSUM - Driver (device) is only able to checksum plain + * TCP or UDP packets over IPv4. These are specifically + * unencapsulated packets of the form IPv4|TCP or + * IPv4|UDP where the Protocol field in the IPv4 header + * is TCP or UDP. The IPv4 header may contain IP options + * This feature cannot be set in features for a device + * with NETIF_F_HW_CSUM also set. This feature is being + * DEPRECATED (see below). + * + * NETIF_F_IPV6_CSUM - Driver (device) is only able to checksum plain + * TCP or UDP packets over IPv6. These are specifically + * unencapsulated packets of the form IPv6|TCP or + * IPv4|UDP where the Next Header field in the IPv6 + * header is either TCP or UDP. IPv6 extension headers + * are not supported with this feature. This feature + * cannot be set in features for a device with + * NETIF_F_HW_CSUM also set. This feature is being + * DEPRECATED (see below). + * + * NETIF_F_RXCSUM - Driver (device) performs receive checksum offload. + * This flag is used only used to disable the RX checksum + * feature for a device. The stack will accept receive + * checksum indication in packets received on a device + * regardless of whether NETIF_F_RXCSUM is set. + * + * B. Checksumming of received packets by device. Indication of checksum + * verification is in set skb->ip_summed. Possible values are: * * CHECKSUM_NONE: * - * Device failed to checksum this packet e.g. due to lack of capabilities. + * Device did not checksum this packet e.g. due to lack of capabilities. * The packet contains full (though not verified) checksum in packet but * not in skb->csum. Thus, skb->csum is undefined in this case. * @@ -53,9 +97,8 @@ * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY * if their checksums are okay. skb->csum is still undefined in this case - * though. It is a bad option, but, unfortunately, nowadays most vendors do - * this. Apparently with the secret goal to sell you new devices, when you - * will add new protocol to your host, f.e. IPv6 8) + * though. A driver or device must never modify the checksum field in the + * packet even if checksum is verified. * * CHECKSUM_UNNECESSARY is applicable to following protocols: * TCP: IPv6 and IPv4. @@ -96,40 +139,77 @@ * packet that are after the checksum being offloaded are not considered to * be verified. * - * B. Checksumming on output. + * C. Checksumming on transmit for non-GSO. The stack requests checksum offload + * in the skb->ip_summed for a packet. Values are: + * + * CHECKSUM_PARTIAL: + * + * The driver is required to checksum the packet as seen by hard_start_xmit() + * from skb->csum_start up to the end, and to record/write the checksum at + * offset skb->csum_start + skb->csum_offset. A driver may verify that the + * csum_start and csum_offset values are valid values given the length and + * offset of the packet, however they should not attempt to validate that the + * checksum refers to a legitimate transport layer checksum-- it is the + * purview of the stack to validate that csum_start and csum_offset are set + * correctly. + * + * When the stack requests checksum offload for a packet, the driver MUST + * ensure that the checksum is set correctly. A driver can either offload the + * checksum calculation to the device, or call skb_checksum_help (in the case + * that the device does not support offload for a particular checksum). + * + * NETIF_F_IP_CSUM and NETIF_F_IPV6_CSUM are being deprecated in favor of + * NETIF_F_HW_CSUM. New devices should use NETIF_F_HW_CSUM to indicate + * checksum offload capability. If a device has limited checksum capabilities + * (for instance can only perform NETIF_F_IP_CSUM or NETIF_F_IPV6_CSUM as + * described above) a helper function can be called to resolve + * CHECKSUM_PARTIAL. The helper functions are skb_csum_off_chk*. The helper + * function takes a spec argument that describes the protocol layer that is + * supported for checksum offload and can be called for each packet. If a + * packet does not match the specification for offload, skb_checksum_help + * is called to resolve the checksum. * * CHECKSUM_NONE: * * The skb was already checksummed by the protocol, or a checksum is not * required. * - * CHECKSUM_PARTIAL: - * - * The device is required to checksum the packet as seen by hard_start_xmit() - * from skb->csum_start up to the end, and to record/write the checksum at - * offset skb->csum_start + skb->csum_offset. - * - * The device must show its capabilities in dev->features, set up at device - * setup time, e.g. netdev_features.h: - * - * NETIF_F_HW_CSUM - It's a clever device, it's able to checksum everything. - * NETIF_F_IP_CSUM - Device is dumb, it's able to checksum only TCP/UDP over - * IPv4. Sigh. Vendors like this way for an unknown reason. - * Though, see comment above about CHECKSUM_UNNECESSARY. 8) - * NETIF_F_IPV6_CSUM - About as dumb as the last one but does IPv6 instead. - * NETIF_F_... - Well, you get the picture. - * * CHECKSUM_UNNECESSARY: * - * Normally, the device will do per protocol specific checksumming. Protocol - * implementations that do not want the NIC to perform the checksum - * calculation should use this flag in their outgoing skbs. + * This has the same meaning on as CHECKSUM_NONE for checksum offload on + * output. * - * NETIF_F_FCOE_CRC - This indicates that the device can do FCoE FC CRC - * offload. Correspondingly, the FCoE protocol driver - * stack should use CHECKSUM_UNNECESSARY. + * CHECKSUM_COMPLETE: + * Not used in checksum output. If a driver observes a packet with this value + * set in skbuff, if should treat as CHECKSUM_NONE being set. * - * Any questions? No questions, good. --ANK + * D. Non-IP checksum (CRC) offloads + * + * NETIF_F_SCTP_CRC - This feature indicates that a device is capable of + * offloading the SCTP CRC in a packet. To perform this offload the stack + * will set ip_summed to CHECKSUM_PARTIAL and set csum_start and csum_offset + * accordingly. Note the there is no indication in the skbuff that the + * CHECKSUM_PARTIAL refers to an SCTP checksum, a driver that supports + * both IP checksum offload and SCTP CRC offload must verify which offload + * is configured for a packet presumably by inspecting packet headers. + * + * NETIF_F_FCOE_CRC - This feature indicates that a device is capable of + * offloading the FCOE CRC in a packet. To perform this offload the stack + * will set ip_summed to CHECKSUM_PARTIAL and set csum_start and csum_offset + * accordingly. Note the there is no indication in the skbuff that the + * CHECKSUM_PARTIAL refers to an FCOE checksum, a driver that supports + * both IP checksum offload and FCOE CRC offload must verify which offload + * is configured for a packet presumably by inspecting packet headers. + * + * E. Checksumming on output with GSO. + * + * In the case of a GSO packet (skb_is_gso(skb) is true), checksum offload + * is implied by the SKB_GSO_* flags in gso_type. Most obviously, if the + * gso_type is SKB_GSO_TCPV4 or SKB_GSO_TCPV6, TCP checksum offload as + * part of the GSO operation is implied. If a checksum is being offloaded + * with GSO then ip_summed is CHECKSUM_PARTIAL, csum_start and csum_offset + * are set to refer to the outermost checksum being offload (two offloaded + * checksums are possible with UDP encapsulation). */ /* Don't change this without changing skb_csum_unnecessary! */