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.
Signed-off-by: Alexander Duyck <adu...@mirantis.com>
---
include/linux/netdev_features.h | 3 +++
include/linux/netdevice.h | 1 +
include/linux/skbuff.h | 20 +++++++++++---------
net/core/ethtool.c | 1 +
net/ipv4/af_inet.c | 19 +++++++++++--------
net/ipv4/gre_offload.c | 1 +
net/ipv4/tcp_offload.c | 4 +++-
net/ipv6/ip6_offload.c | 3 ++-
8 files changed, 33 insertions(+), 19 deletions(-)
diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index a734bf43d190..5d7da1ac6df5 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_FIXEDID_BIT, /* ... IPV4 header has fixed IP ID */
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_FIXEDID __NETIF_F(TSO_FIXEDID)
#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_FIXEDID | \
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 8395308a2445..38ccc01eb97d 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4011,6 +4011,7 @@ 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_FIXEDID >>
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 007381270ff8..5fba16658f9d 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/ethtool.c b/net/core/ethtool.c
index 6a7f99661c2f..5340c9dbc318 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_FIXEDID_BIT] = "tx-tcp-fixedid-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 a38b9910af60..19e9a2c45d71 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 6a5bd4317866..6376b0cdf693 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 773083b7f1e9..08dd25d835af 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 82e9f3076028..d7530b9a1d63 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;
