From 2abb7cdc0dc84e99b76ef983a1ae1978922aa9b3 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Sun, 31 Aug 2014 15:12:43 -0700 Subject: [PATCH] udp: Add support for doing checksum unnecessary conversion Add support for doing CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion in UDP tunneling path. In the normal UDP path, we call skb_checksum_try_convert after locating the UDP socket. The check is that checksum conversion is enabled for the socket (new flag in UDP socket) and that checksum field is non-zero. In the UDP GRO path, we call skb_gro_checksum_try_convert after checksum is validated and checksum field is non-zero. Since this is already in GRO we assume that checksum conversion is always wanted. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/linux/udp.h | 16 +++++++++++++++- net/ipv4/udp.c | 4 ++++ net/ipv4/udp_offload.c | 25 +++++++++++++++++-------- net/ipv6/udp.c | 4 ++++ net/ipv6/udp_offload.c | 24 +++++++++++++++++------- 5 files changed, 57 insertions(+), 16 deletions(-) diff --git a/include/linux/udp.h b/include/linux/udp.h index 247cfdcc4b08..ee3277593222 100644 --- a/include/linux/udp.h +++ b/include/linux/udp.h @@ -49,7 +49,11 @@ struct udp_sock { unsigned int corkflag; /* Cork is required */ __u8 encap_type; /* Is this an Encapsulation socket? */ unsigned char no_check6_tx:1,/* Send zero UDP6 checksums on TX? */ - no_check6_rx:1;/* Allow zero UDP6 checksums on RX? */ + no_check6_rx:1,/* Allow zero UDP6 checksums on RX? */ + convert_csum:1;/* On receive, convert checksum + * unnecessary to checksum complete + * if possible. + */ /* * Following member retains the information to create a UDP header * when the socket is uncorked. @@ -98,6 +102,16 @@ static inline bool udp_get_no_check6_rx(struct sock *sk) return udp_sk(sk)->no_check6_rx; } +static inline void udp_set_convert_csum(struct sock *sk, bool val) +{ + udp_sk(sk)->convert_csum = val; +} + +static inline bool udp_get_convert_csum(struct sock *sk) +{ + return udp_sk(sk)->convert_csum; +} + #define udp_portaddr_for_each_entry(__sk, node, list) \ hlist_nulls_for_each_entry(__sk, node, list, __sk_common.skc_portaddr_node) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 3549c21fe5f7..0da3849fd35b 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1788,6 +1788,10 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, if (sk != NULL) { int ret; + if (udp_sk(sk)->convert_csum && uh->check && !IS_UDPLITE(sk)) + skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check, + inet_compute_pseudo); + ret = udp_queue_rcv_skb(sk, skb); sock_put(sk); diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index a6adff98382a..84e0e05c9c0e 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -290,16 +290,25 @@ static struct sk_buff **udp4_gro_receive(struct sk_buff **head, { struct udphdr *uh = udp_gro_udphdr(skb); - /* Don't bother verifying checksum if we're going to flush anyway. */ - if (unlikely(!uh) || - (!NAPI_GRO_CB(skb)->flush && - skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check, - inet_gro_compute_pseudo))) { - NAPI_GRO_CB(skb)->flush = 1; - return NULL; - } + if (unlikely(!uh)) + goto flush; + /* Don't bother verifying checksum if we're going to flush anyway. */ + if (!NAPI_GRO_CB(skb)->flush) + goto skip; + + if (skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check, + inet_gro_compute_pseudo)) + goto flush; + else if (uh->check) + skb_gro_checksum_try_convert(skb, IPPROTO_UDP, uh->check, + inet_gro_compute_pseudo); +skip: return udp_gro_receive(head, skb, uh); + +flush: + NAPI_GRO_CB(skb)->flush = 1; + return NULL; } int udp_gro_complete(struct sk_buff *skb, int nhoff) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 12fcce8fba46..f6ba535b6feb 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -891,6 +891,10 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, goto csum_error; } + if (udp_sk(sk)->convert_csum && uh->check && !IS_UDPLITE(sk)) + skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check, + ip6_compute_pseudo); + ret = udpv6_queue_rcv_skb(sk, skb); sock_put(sk); diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c index b13e377e9c53..89cb9a9b8537 100644 --- a/net/ipv6/udp_offload.c +++ b/net/ipv6/udp_offload.c @@ -134,16 +134,26 @@ static struct sk_buff **udp6_gro_receive(struct sk_buff **head, { struct udphdr *uh = udp_gro_udphdr(skb); + if (unlikely(!uh)) + goto flush; + /* Don't bother verifying checksum if we're going to flush anyway. */ - if (unlikely(!uh) || - (!NAPI_GRO_CB(skb)->flush && - skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check, - ip6_gro_compute_pseudo))) { - NAPI_GRO_CB(skb)->flush = 1; - return NULL; - } + if (!NAPI_GRO_CB(skb)->flush) + goto skip; + if (skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check, + ip6_gro_compute_pseudo)) + goto flush; + else if (uh->check) + skb_gro_checksum_try_convert(skb, IPPROTO_UDP, uh->check, + ip6_gro_compute_pseudo); + +skip: return udp_gro_receive(head, skb, uh); + +flush: + NAPI_GRO_CB(skb)->flush = 1; + return NULL; } int udp6_gro_complete(struct sk_buff *skb, int nhoff) -- 2.20.1