| Message ID | 20210323003808.16074-9-xiyou.wangcong@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | sockmap: introduce BPF_SK_SKB_VERDICT and support UDP | expand |
On Mon, Mar 22, 2021 at 11:31 PM Yunsheng Lin <linyunsheng@huawei.com> wrote: > > On 2021/3/23 8:38, Cong Wang wrote: > > From: Cong Wang <cong.wang@bytedance.com> > > > > This is similar to tcp_read_sock(), except we do not need > > to worry about connections, we just need to retrieve skb > > from UDP receive queue. > > > > Cc: John Fastabend <john.fastabend@gmail.com> > > Cc: Daniel Borkmann <daniel@iogearbox.net> > > Cc: Jakub Sitnicki <jakub@cloudflare.com> > > Cc: Lorenz Bauer <lmb@cloudflare.com> > > Signed-off-by: Cong Wang <cong.wang@bytedance.com> > > --- > > include/net/udp.h | 2 ++ > > net/ipv4/af_inet.c | 1 + > > net/ipv4/udp.c | 35 +++++++++++++++++++++++++++++++++++ > > net/ipv6/af_inet6.c | 1 + > > 4 files changed, 39 insertions(+) > > > > diff --git a/include/net/udp.h b/include/net/udp.h > > index df7cc1edc200..347b62a753c3 100644 > > --- a/include/net/udp.h > > +++ b/include/net/udp.h > > @@ -329,6 +329,8 @@ struct sock *__udp6_lib_lookup(struct net *net, > > struct sk_buff *skb); > > struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, > > __be16 sport, __be16 dport); > > +int udp_read_sock(struct sock *sk, read_descriptor_t *desc, > > + sk_read_actor_t recv_actor); > > > > /* UDP uses skb->dev_scratch to cache as much information as possible and avoid > > * possibly multiple cache miss on dequeue() > > diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c > > index 1355e6c0d567..f17870ee558b 100644 > > --- a/net/ipv4/af_inet.c > > +++ b/net/ipv4/af_inet.c > > @@ -1070,6 +1070,7 @@ const struct proto_ops inet_dgram_ops = { > > .setsockopt = sock_common_setsockopt, > > .getsockopt = sock_common_getsockopt, > > .sendmsg = inet_sendmsg, > > + .read_sock = udp_read_sock, > > .recvmsg = inet_recvmsg, > > .mmap = sock_no_mmap, > > .sendpage = inet_sendpage, > > diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c > > index 38952aaee3a1..a0adee3b1af4 100644 > > --- a/net/ipv4/udp.c > > +++ b/net/ipv4/udp.c > > @@ -1782,6 +1782,41 @@ struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags, > > } > > EXPORT_SYMBOL(__skb_recv_udp); > > > > +int udp_read_sock(struct sock *sk, read_descriptor_t *desc, > > + sk_read_actor_t recv_actor) > > +{ > > + int copied = 0; > > + > > + while (1) { > > + int offset = 0, err; > > + struct sk_buff *skb; > > + > > + skb = __skb_recv_udp(sk, 0, 1, &offset, &err); > > + if (!skb) > > + break; > > Does above error handling need the below additional handling? > It seems __skb_recv_udp() will return the error by parameter "err", > if "copied == 0", does it need to return the error? Not for skmsg case, because the return value is just unused: static void sk_psock_verdict_data_ready(struct sock *sk) { struct socket *sock = sk->sk_socket; read_descriptor_t desc; if (unlikely(!sock || !sock->ops || !sock->ops->read_sock)) return; desc.arg.data = sk; desc.error = 0; desc.count = 1; sock->ops->read_sock(sk, &desc, sk_psock_verdict_recv); } Thanks.
diff --git a/include/net/udp.h b/include/net/udp.h index df7cc1edc200..347b62a753c3 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -329,6 +329,8 @@ struct sock *__udp6_lib_lookup(struct net *net, struct sk_buff *skb); struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, __be16 sport, __be16 dport); +int udp_read_sock(struct sock *sk, read_descriptor_t *desc, + sk_read_actor_t recv_actor); /* UDP uses skb->dev_scratch to cache as much information as possible and avoid * possibly multiple cache miss on dequeue() diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 1355e6c0d567..f17870ee558b 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1070,6 +1070,7 @@ const struct proto_ops inet_dgram_ops = { .setsockopt = sock_common_setsockopt, .getsockopt = sock_common_getsockopt, .sendmsg = inet_sendmsg, + .read_sock = udp_read_sock, .recvmsg = inet_recvmsg, .mmap = sock_no_mmap, .sendpage = inet_sendpage, diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 38952aaee3a1..a0adee3b1af4 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1782,6 +1782,41 @@ struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags, } EXPORT_SYMBOL(__skb_recv_udp); +int udp_read_sock(struct sock *sk, read_descriptor_t *desc, + sk_read_actor_t recv_actor) +{ + int copied = 0; + + while (1) { + int offset = 0, err; + struct sk_buff *skb; + + skb = __skb_recv_udp(sk, 0, 1, &offset, &err); + if (!skb) + break; + if (offset < skb->len) { + int used; + size_t len; + + len = skb->len - offset; + used = recv_actor(desc, skb, offset, len); + if (used <= 0) { + if (!copied) + copied = used; + break; + } else if (used <= len) { + copied += used; + offset += used; + } + } + if (!desc->count) + break; + } + + return copied; +} +EXPORT_SYMBOL(udp_read_sock); + /* * This should be easy, if there is something there we * return it, otherwise we block. diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 802f5111805a..71de739b4a9e 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -714,6 +714,7 @@ const struct proto_ops inet6_dgram_ops = { .getsockopt = sock_common_getsockopt, /* ok */ .sendmsg = inet6_sendmsg, /* retpoline's sake */ .recvmsg = inet6_recvmsg, /* retpoline's sake */ + .read_sock = udp_read_sock, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage, .set_peek_off = sk_set_peek_off,