[PATCH bpf-next v6 1/5] af_unix: add read_sock for stream socket types

From: Jiang Wang
Date: Mon Aug 09 2021 - 15:48:07 EST


To support sockmap for af_unix stream type, implement
read_sock, which is similar to the read_sock for unix
dgram sockets.

Signed-off-by: Jiang Wang <jiang.wang@xxxxxxxxxxxxx>
Reviewed-by: Cong Wang <cong.wang@xxxxxxxxxxxxx>
---
net/unix/af_unix.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 256c4e31132e..c020ad0e8438 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -672,6 +672,8 @@ static int unix_dgram_sendmsg(struct socket *, struct msghdr *, size_t);
static int unix_dgram_recvmsg(struct socket *, struct msghdr *, size_t, int);
static int unix_read_sock(struct sock *sk, read_descriptor_t *desc,
sk_read_actor_t recv_actor);
+static int unix_stream_read_sock(struct sock *sk, read_descriptor_t *desc,
+ sk_read_actor_t recv_actor);
static int unix_dgram_connect(struct socket *, struct sockaddr *,
int, int);
static int unix_seqpacket_sendmsg(struct socket *, struct msghdr *, size_t);
@@ -725,6 +727,7 @@ static const struct proto_ops unix_stream_ops = {
.shutdown = unix_shutdown,
.sendmsg = unix_stream_sendmsg,
.recvmsg = unix_stream_recvmsg,
+ .read_sock = unix_stream_read_sock,
.mmap = sock_no_mmap,
.sendpage = unix_stream_sendpage,
.splice_read = unix_stream_splice_read,
@@ -2358,6 +2361,15 @@ struct unix_stream_read_state {
unsigned int splice_flags;
};

+static int unix_stream_read_sock(struct sock *sk, read_descriptor_t *desc,
+ sk_read_actor_t recv_actor)
+{
+ if (unlikely(sk->sk_state != TCP_ESTABLISHED))
+ return -ENOTCONN;
+
+ return unix_read_sock(sk, desc, recv_actor);
+}
+
static int unix_stream_read_generic(struct unix_stream_read_state *state,
bool freezable)
{
--
2.20.1