[Patch bpf-next v7 09/13] udp: implement ->read_sock() for sockmap
From: Cong Wang <hidden>
Date: 2021-03-28 20:21:21
Also in:
bpf
Subsystem:
networking [general], the rest, user datagram protocol (udp) · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Willem de Bruijn
From: Cong Wang <redacted> 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. Note, the return value of ->read_sock() is unused in sk_psock_verdict_data_ready(). Cc: John Fastabend <john.fastabend@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jakub Sitnicki <jakub@cloudflare.com> Cc: Lorenz Bauer <redacted> Signed-off-by: Cong Wang <redacted> --- 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..04620e4d64ab 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) + return err; + if (offset < skb->len) { + size_t len; + int used; + + 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,
--
2.25.1