From: Alexander Duyck Date: Mon, 11 Apr 2016 01:44:51 +0000 (-0400) Subject: GSO: Add GSO type for fixed IPv4 ID X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=cbc53e08a793b073e79f42ca33f1f3568703540d;p=linux.git GSO: Add GSO type for fixed IPv4 ID This patch adds support for TSO using IPv4 headers with a fixed IP ID field. This is meant to allow us to do a lossless GRO in the case of TCP flows that use a fixed IP ID such as those that convert IPv6 header to IPv4 headers. In addition I am adding a feature that for now I am referring to TSO with IP ID mangling. Basically when this flag is enabled the device has the option to either output the flow with incrementing IP IDs or with a fixed IP ID regardless of what the original IP ID ordering was. This is useful in cases where the DF bit is set and we do not care if the original IP ID value is maintained. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller --- diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h index a734bf43d1902..7cf272a4b5c85 100644 --- a/include/linux/netdev_features.h +++ b/include/linux/netdev_features.h @@ -39,6 +39,7 @@ enum { NETIF_F_UFO_BIT, /* ... UDPv4 fragmentation */ NETIF_F_GSO_ROBUST_BIT, /* ... ->SKB_GSO_DODGY */ NETIF_F_TSO_ECN_BIT, /* ... TCP ECN support */ + NETIF_F_TSO_MANGLEID_BIT, /* ... IPV4 ID mangling allowed */ NETIF_F_TSO6_BIT, /* ... TCPv6 segmentation */ NETIF_F_FSO_BIT, /* ... FCoE segmentation */ NETIF_F_GSO_GRE_BIT, /* ... GRE with TSO */ @@ -120,6 +121,7 @@ enum { #define NETIF_F_GSO_SIT __NETIF_F(GSO_SIT) #define NETIF_F_GSO_UDP_TUNNEL __NETIF_F(GSO_UDP_TUNNEL) #define NETIF_F_GSO_UDP_TUNNEL_CSUM __NETIF_F(GSO_UDP_TUNNEL_CSUM) +#define NETIF_F_TSO_MANGLEID __NETIF_F(TSO_MANGLEID) #define NETIF_F_GSO_TUNNEL_REMCSUM __NETIF_F(GSO_TUNNEL_REMCSUM) #define NETIF_F_HW_VLAN_STAG_FILTER __NETIF_F(HW_VLAN_STAG_FILTER) #define NETIF_F_HW_VLAN_STAG_RX __NETIF_F(HW_VLAN_STAG_RX) @@ -147,6 +149,7 @@ enum { /* List of features with software fallbacks. */ #define NETIF_F_GSO_SOFTWARE (NETIF_F_TSO | NETIF_F_TSO_ECN | \ + NETIF_F_TSO_MANGLEID | \ NETIF_F_TSO6 | NETIF_F_UFO) /* List of IP checksum features. Note that NETIF_F_ HW_CSUM should not be diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 9884fe9a6552a..8e372d01b3c19 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3992,6 +3992,7 @@ static inline bool net_gso_ok(netdev_features_t features, int gso_type) BUILD_BUG_ON(SKB_GSO_UDP != (NETIF_F_UFO >> NETIF_F_GSO_SHIFT)); BUILD_BUG_ON(SKB_GSO_DODGY != (NETIF_F_GSO_ROBUST >> NETIF_F_GSO_SHIFT)); BUILD_BUG_ON(SKB_GSO_TCP_ECN != (NETIF_F_TSO_ECN >> NETIF_F_GSO_SHIFT)); + BUILD_BUG_ON(SKB_GSO_TCP_FIXEDID != (NETIF_F_TSO_MANGLEID >> NETIF_F_GSO_SHIFT)); BUILD_BUG_ON(SKB_GSO_TCPV6 != (NETIF_F_TSO6 >> NETIF_F_GSO_SHIFT)); BUILD_BUG_ON(SKB_GSO_FCOE != (NETIF_F_FSO >> NETIF_F_GSO_SHIFT)); BUILD_BUG_ON(SKB_GSO_GRE != (NETIF_F_GSO_GRE >> NETIF_F_GSO_SHIFT)); diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 007381270ff8d..5fba16658f9dd 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -465,23 +465,25 @@ enum { /* This indicates the tcp segment has CWR set. */ SKB_GSO_TCP_ECN = 1 << 3, - SKB_GSO_TCPV6 = 1 << 4, + SKB_GSO_TCP_FIXEDID = 1 << 4, - SKB_GSO_FCOE = 1 << 5, + SKB_GSO_TCPV6 = 1 << 5, - SKB_GSO_GRE = 1 << 6, + SKB_GSO_FCOE = 1 << 6, - SKB_GSO_GRE_CSUM = 1 << 7, + SKB_GSO_GRE = 1 << 7, - SKB_GSO_IPIP = 1 << 8, + SKB_GSO_GRE_CSUM = 1 << 8, - SKB_GSO_SIT = 1 << 9, + SKB_GSO_IPIP = 1 << 9, - SKB_GSO_UDP_TUNNEL = 1 << 10, + SKB_GSO_SIT = 1 << 10, - SKB_GSO_UDP_TUNNEL_CSUM = 1 << 11, + SKB_GSO_UDP_TUNNEL = 1 << 11, - SKB_GSO_TUNNEL_REMCSUM = 1 << 12, + SKB_GSO_UDP_TUNNEL_CSUM = 1 << 12, + + SKB_GSO_TUNNEL_REMCSUM = 1 << 13, }; #if BITS_PER_LONG > 32 diff --git a/net/core/dev.c b/net/core/dev.c index 09fb1ace9dc84..e896b1953ab6b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2825,14 +2825,36 @@ static netdev_features_t dflt_features_check(const struct sk_buff *skb, return vlan_features_check(skb, features); } +static netdev_features_t gso_features_check(const struct sk_buff *skb, + struct net_device *dev, + netdev_features_t features) +{ + u16 gso_segs = skb_shinfo(skb)->gso_segs; + + if (gso_segs > dev->gso_max_segs) + return features & ~NETIF_F_GSO_MASK; + + /* Make sure to clear the IPv4 ID mangling feature if + * the IPv4 header has the potential to be fragmented. + */ + if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { + struct iphdr *iph = skb->encapsulation ? + inner_ip_hdr(skb) : ip_hdr(skb); + + if (!(iph->frag_off & htons(IP_DF))) + features &= ~NETIF_F_TSO_MANGLEID; + } + + return features; +} + netdev_features_t netif_skb_features(struct sk_buff *skb) { struct net_device *dev = skb->dev; netdev_features_t features = dev->features; - u16 gso_segs = skb_shinfo(skb)->gso_segs; - if (gso_segs > dev->gso_max_segs) - features &= ~NETIF_F_GSO_MASK; + if (skb_is_gso(skb)) + features = gso_features_check(skb, dev, features); /* If encapsulation offload request, verify we are testing * hardware encapsulation features instead of standard @@ -6976,9 +6998,11 @@ int register_netdevice(struct net_device *dev) dev->features |= NETIF_F_SOFT_FEATURES; dev->wanted_features = dev->features & dev->hw_features; - if (!(dev->flags & IFF_LOOPBACK)) { + if (!(dev->flags & IFF_LOOPBACK)) dev->hw_features |= NETIF_F_NOCACHE_COPY; - } + + if (dev->hw_features & NETIF_F_TSO) + dev->hw_features |= NETIF_F_TSO_MANGLEID; /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. */ diff --git a/net/core/ethtool.c b/net/core/ethtool.c index 6a7f99661c2fb..9494c41cc77c6 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -79,6 +79,7 @@ static const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] [NETIF_F_UFO_BIT] = "tx-udp-fragmentation", [NETIF_F_GSO_ROBUST_BIT] = "tx-gso-robust", [NETIF_F_TSO_ECN_BIT] = "tx-tcp-ecn-segmentation", + [NETIF_F_TSO_MANGLEID_BIT] = "tx-tcp-mangleid-segmentation", [NETIF_F_TSO6_BIT] = "tx-tcp6-segmentation", [NETIF_F_FSO_BIT] = "tx-fcoe-segmentation", [NETIF_F_GSO_GRE_BIT] = "tx-gre-segmentation", diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 8217cd22f921d..5bbea9a0ce96f 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1195,10 +1195,10 @@ EXPORT_SYMBOL(inet_sk_rebuild_header); static struct sk_buff *inet_gso_segment(struct sk_buff *skb, netdev_features_t features) { + bool udpfrag = false, fixedid = false, encap; struct sk_buff *segs = ERR_PTR(-EINVAL); const struct net_offload *ops; unsigned int offset = 0; - bool udpfrag, encap; struct iphdr *iph; int proto; int nhoff; @@ -1217,6 +1217,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, SKB_GSO_TCPV6 | SKB_GSO_UDP_TUNNEL | SKB_GSO_UDP_TUNNEL_CSUM | + SKB_GSO_TCP_FIXEDID | SKB_GSO_TUNNEL_REMCSUM | 0))) goto out; @@ -1248,11 +1249,14 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, segs = ERR_PTR(-EPROTONOSUPPORT); - if (skb->encapsulation && - skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP)) - udpfrag = proto == IPPROTO_UDP && encap; - else - udpfrag = proto == IPPROTO_UDP && !skb->encapsulation; + if (!skb->encapsulation || encap) { + udpfrag = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP); + fixedid = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TCP_FIXEDID); + + /* fixed ID is invalid if DF bit is not set */ + if (fixedid && !(iph->frag_off & htons(IP_DF))) + goto out; + } ops = rcu_dereference(inet_offloads[proto]); if (likely(ops && ops->callbacks.gso_segment)) @@ -1265,12 +1269,11 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, do { iph = (struct iphdr *)(skb_mac_header(skb) + nhoff); if (udpfrag) { - iph->id = htons(id); iph->frag_off = htons(offset >> 3); if (skb->next) iph->frag_off |= htons(IP_MF); offset += skb->len - nhoff - ihl; - } else { + } else if (!fixedid) { iph->id = htons(id++); } iph->tot_len = htons(skb->len - nhoff); diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c index 6a5bd43178666..6376b0cdf6931 100644 --- a/net/ipv4/gre_offload.c +++ b/net/ipv4/gre_offload.c @@ -32,6 +32,7 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb, SKB_GSO_UDP | SKB_GSO_DODGY | SKB_GSO_TCP_ECN | + SKB_GSO_TCP_FIXEDID | SKB_GSO_GRE | SKB_GSO_GRE_CSUM | SKB_GSO_IPIP | diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c index 773083b7f1e98..08dd25d835af9 100644 --- a/net/ipv4/tcp_offload.c +++ b/net/ipv4/tcp_offload.c @@ -89,6 +89,7 @@ struct sk_buff *tcp_gso_segment(struct sk_buff *skb, ~(SKB_GSO_TCPV4 | SKB_GSO_DODGY | SKB_GSO_TCP_ECN | + SKB_GSO_TCP_FIXEDID | SKB_GSO_TCPV6 | SKB_GSO_GRE | SKB_GSO_GRE_CSUM | @@ -98,7 +99,8 @@ struct sk_buff *tcp_gso_segment(struct sk_buff *skb, SKB_GSO_UDP_TUNNEL_CSUM | SKB_GSO_TUNNEL_REMCSUM | 0) || - !(type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))) + !(type & (SKB_GSO_TCPV4 | + SKB_GSO_TCPV6)))) goto out; skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss); diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index 204af22194713..b3a779393d713 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -73,6 +73,8 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, SKB_GSO_UDP | SKB_GSO_DODGY | SKB_GSO_TCP_ECN | + SKB_GSO_TCP_FIXEDID | + SKB_GSO_TCPV6 | SKB_GSO_GRE | SKB_GSO_GRE_CSUM | SKB_GSO_IPIP | @@ -80,7 +82,6 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, SKB_GSO_UDP_TUNNEL | SKB_GSO_UDP_TUNNEL_CSUM | SKB_GSO_TUNNEL_REMCSUM | - SKB_GSO_TCPV6 | 0))) goto out; diff --git a/net/mpls/mpls_gso.c b/net/mpls/mpls_gso.c index 0183b32da9427..bbcf60465e5c4 100644 --- a/net/mpls/mpls_gso.c +++ b/net/mpls/mpls_gso.c @@ -31,6 +31,7 @@ static struct sk_buff *mpls_gso_segment(struct sk_buff *skb, SKB_GSO_TCPV6 | SKB_GSO_UDP | SKB_GSO_DODGY | + SKB_GSO_TCP_FIXEDID | SKB_GSO_TCP_ECN))) goto out;