skmsg: Extract and reuse sk_msg_is_readable()

tcp_bpf_sock_is_readable() is pretty much generic,
we can extract it and reuse it for non-TCP sockets.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211008203306.37525-3-xiyou.wangcong@gmail.com

diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h
index 14ab0c0..1ce9a9e 100644 (file)
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -128,6 +128,7 @@ int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
                             struct sk_msg *msg, u32 bytes);
 int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
                   int len, int flags);
+bool sk_msg_is_readable(struct sock *sk);
 
 static inline void sk_msg_check_to_free(struct sk_msg *msg, u32 i, u32 bytes)
 {

diff --git a/net/core/skmsg.c b/net/core/skmsg.c
index 2d6249b..a86ef7e 100644 (file)
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -474,6 +474,20 @@ int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg,
 }
 EXPORT_SYMBOL_GPL(sk_msg_recvmsg);
 
+bool sk_msg_is_readable(struct sock *sk)
+{
+       struct sk_psock *psock;
+       bool empty = true;
+
+       rcu_read_lock();
+       psock = sk_psock(sk);
+       if (likely(psock))
+               empty = list_empty(&psock->ingress_msg);
+       rcu_read_unlock();
+       return !empty;
+}
+EXPORT_SYMBOL_GPL(sk_msg_is_readable);
+
 static struct sk_msg *sk_psock_create_ingress_msg(struct sock *sk,
                                                  struct sk_buff *skb)
 {

diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c
index 7e71e9e..5f4d6f4 100644 (file)
--- a/net/ipv4/tcp_bpf.c
+++ b/net/ipv4/tcp_bpf.c
@@ -150,19 +150,6 @@ int tcp_bpf_sendmsg_redir(struct sock *sk, struct sk_msg *msg,
 EXPORT_SYMBOL_GPL(tcp_bpf_sendmsg_redir);
 
 #ifdef CONFIG_BPF_SYSCALL
-static bool tcp_bpf_sock_is_readable(struct sock *sk)
-{
-       struct sk_psock *psock;
-       bool empty = true;
-
-       rcu_read_lock();
-       psock = sk_psock(sk);
-       if (likely(psock))
-               empty = list_empty(&psock->ingress_msg);
-       rcu_read_unlock();
-       return !empty;
-}
-
 static int tcp_msg_wait_data(struct sock *sk, struct sk_psock *psock,
                             long timeo)
 {
@@ -491,7 +478,7 @@ static void tcp_bpf_rebuild_protos(struct proto prot[TCP_BPF_NUM_CFGS],
        prot[TCP_BPF_BASE].unhash               = sock_map_unhash;
        prot[TCP_BPF_BASE].close                = sock_map_close;
        prot[TCP_BPF_BASE].recvmsg              = tcp_bpf_recvmsg;
-       prot[TCP_BPF_BASE].sock_is_readable     = tcp_bpf_sock_is_readable;
+       prot[TCP_BPF_BASE].sock_is_readable     = sk_msg_is_readable;
 
        prot[TCP_BPF_TX]                        = prot[TCP_BPF_BASE];
        prot[TCP_BPF_TX].sendmsg                = tcp_bpf_sendmsg;