From d7f571188ecf25c244789b883c878ec7c64b5b08 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 30 Mar 2021 19:32:32 -0700 Subject: udp: Implement ->read_sock() for sockmap 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(), and UDP still does not support splice() due to lack of ->splice_read(), so users can not reach udp_read_sock() directly. Signed-off-by: Cong Wang Signed-off-by: Alexei Starovoitov Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20210331023237.41094-12-xiyou.wangcong@gmail.com --- net/ipv4/af_inet.c | 1 + net/ipv4/udp.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 30 insertions(+) (limited to 'net/ipv4') 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..4d02f6839e38 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1782,6 +1782,35 @@ busy_check: } 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) { + struct sk_buff *skb; + int err, used; + + skb = skb_recv_udp(sk, 0, 1, &err); + if (!skb) + return err; + used = recv_actor(desc, skb, 0, skb->len); + if (used <= 0) { + if (!copied) + copied = used; + break; + } else if (used <= skb->len) { + copied += 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. -- cgit v1.2.3-58-ga151