From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Herbert Subject: Re: [PATCH v2 net-next 4/6] udp: flow dissector offload Date: Wed, 30 Aug 2017 07:56:44 -0700 Message-ID: References: <20170829232711.1465-1-tom@quantonium.net> <20170829232711.1465-5-tom@quantonium.net> <1504089372.2480.55.camel@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: "David S . Miller" , Linux Kernel Network Developers To: Paolo Abeni Return-path: Received: from mail-wr0-f179.google.com ([209.85.128.179]:38398 "EHLO mail-wr0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751323AbdH3O4q (ORCPT ); Wed, 30 Aug 2017 10:56:46 -0400 Received: by mail-wr0-f179.google.com with SMTP id 40so18708320wrv.5 for ; Wed, 30 Aug 2017 07:56:46 -0700 (PDT) In-Reply-To: <1504089372.2480.55.camel@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Aug 30, 2017 at 3:36 AM, Paolo Abeni wrote: > On Tue, 2017-08-29 at 16:27 -0700, Tom Herbert wrote: >> Add support to perform UDP specific flow dissection. This is >> primarily intended for dissecting encapsulated packets in UDP >> encapsulation. >> >> This patch adds a flow_dissect offload for UDP4 and UDP6. The backend >> function performs a socket lookup and calls the flow_dissect function >> if a socket is found. >> >> Signed-off-by: Tom Herbert >> --- >> include/linux/udp.h | 8 ++++++++ >> include/net/udp.h | 8 ++++++++ >> include/net/udp_tunnel.h | 8 ++++++++ >> net/ipv4/udp_offload.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ >> net/ipv4/udp_tunnel.c | 1 + >> net/ipv6/udp_offload.c | 13 +++++++++++++ >> 6 files changed, 83 insertions(+) >> >> diff --git a/include/linux/udp.h b/include/linux/udp.h >> index eaea63bc79bb..2e90b189ef6a 100644 >> --- a/include/linux/udp.h >> +++ b/include/linux/udp.h >> @@ -79,6 +79,14 @@ struct udp_sock { >> int (*gro_complete)(struct sock *sk, >> struct sk_buff *skb, >> int nhoff); >> + /* Flow dissector function for a UDP socket */ >> + enum flow_dissect_ret (*flow_dissect)(struct sock *sk, >> + const struct sk_buff *skb, >> + struct flow_dissector_key_control *key_control, >> + struct flow_dissector *flow_dissector, >> + void *target_container, void *data, >> + __be16 *p_proto, u8 *p_ip_proto, int *p_nhoff, >> + int *p_hlen, unsigned int flags); >> >> /* udp_recvmsg try to use this before splicing sk_receive_queue */ >> struct sk_buff_head reader_queue ____cacheline_aligned_in_smp; >> diff --git a/include/net/udp.h b/include/net/udp.h >> index f3d1de6f0983..499e4faf8b14 100644 >> --- a/include/net/udp.h >> +++ b/include/net/udp.h >> @@ -174,6 +174,14 @@ struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb, >> struct udphdr *uh, udp_lookup_t lookup); >> int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup); >> >> +enum flow_dissect_ret udp_flow_dissect(const struct sk_buff *skb, >> + udp_lookup_t lookup, >> + struct flow_dissector_key_control *key_control, >> + struct flow_dissector *flow_dissector, >> + void *target_container, void *data, >> + __be16 *p_proto, u8 *p_ip_proto, int *p_nhoff, >> + int *p_hlen, unsigned int flags); >> + >> static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb) >> { >> struct udphdr *uh; >> diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h >> index 10cce0dd4450..b7102e0f41a9 100644 >> --- a/include/net/udp_tunnel.h >> +++ b/include/net/udp_tunnel.h >> @@ -69,6 +69,13 @@ typedef struct sk_buff **(*udp_tunnel_gro_receive_t)(struct sock *sk, >> struct sk_buff *skb); >> typedef int (*udp_tunnel_gro_complete_t)(struct sock *sk, struct sk_buff *skb, >> int nhoff); >> +typedef enum flow_dissect_ret (*udp_tunnel_flow_dissect_t)(struct sock *sk, >> + const struct sk_buff *skb, >> + struct flow_dissector_key_control *key_control, >> + struct flow_dissector *flow_dissector, >> + void *target_container, void *data, >> + __be16 *p_proto, u8 *p_ip_proto, int *p_nhoff, >> + int *p_hlen, unsigned int flags); >> >> struct udp_tunnel_sock_cfg { >> void *sk_user_data; /* user data used by encap_rcv call back */ >> @@ -78,6 +85,7 @@ struct udp_tunnel_sock_cfg { >> udp_tunnel_encap_destroy_t encap_destroy; >> udp_tunnel_gro_receive_t gro_receive; >> udp_tunnel_gro_complete_t gro_complete; >> + udp_tunnel_flow_dissect_t flow_dissect; >> }; >> >> /* Setup the given (UDP) sock to receive UDP encapsulated packets */ >> diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c >> index 97658bfc1b58..7f0a7ed4a6f7 100644 >> --- a/net/ipv4/udp_offload.c >> +++ b/net/ipv4/udp_offload.c >> @@ -328,11 +328,56 @@ static int udp4_gro_complete(struct sk_buff *skb, int nhoff) >> return udp_gro_complete(skb, nhoff, udp4_lib_lookup_skb); >> } >> >> +enum flow_dissect_ret udp_flow_dissect(const struct sk_buff *skb, >> + udp_lookup_t lookup, >> + struct flow_dissector_key_control *key_control, >> + struct flow_dissector *flow_dissector, >> + void *target_container, void *data, >> + __be16 *p_proto, u8 *p_ip_proto, int *p_nhoff, >> + int *p_hlen, unsigned int flags) >> +{ >> + enum flow_dissect_ret ret = FLOW_DISSECT_RET_CONTINUE; >> + struct udphdr *uh, _uh; >> + struct sock *sk; >> + >> + uh = __skb_header_pointer(skb, *p_nhoff, sizeof(_uh), data, >> + *p_hlen, &_uh); >> + if (!uh) >> + return FLOW_DISSECT_RET_OUT_BAD; >> + >> + rcu_read_lock(); >> + >> + sk = (*lookup)(skb, uh->source, uh->dest); >> + >> + if (sk && udp_sk(sk)->flow_dissect) >> + ret = udp_sk(sk)->flow_dissect(sk, skb, key_control, >> + flow_dissector, target_container, >> + data, p_proto, p_ip_proto, >> + p_nhoff, p_hlen, flags); >> + rcu_read_unlock(); >> + >> + return ret; >> +} >> +EXPORT_SYMBOL(udp_flow_dissect); > > If I read the above correctly, this is going to add another full UDP > lookup per UDP packet, can we avoid it with some static key enabled by > vxlan/fou/etc. ? > That's a good idea! Should just check udp_encap_needed. Also makes sense to have in udp_gro_receive. Tom > Thanks, > > Paolo