net: Rename ->stream_memory_read to ->sock_is_readable

The proto ops ->stream_memory_read() is currently only used
by TCP to check whether psock queue is empty or not. We need
to rename it before reusing it for non-TCP protocols, and
adjust the exsiting users accordingly.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211008203306.37525-2-xiyou.wangcong@gmail.com

include/net/sock.h

@@ -1208,7 +1208,7 @@ struct proto {
 #endif
 
 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
-	bool			(*stream_memory_read)(const struct sock *sk);
+	bool			(*sock_is_readable)(struct sock *sk);
 	/* Memory pressure */
 	void			(*enter_memory_pressure)(struct sock *sk);
 	void			(*leave_memory_pressure)(struct sock *sk);
@@ -2820,4 +2820,10 @@ void sock_set_sndtimeo(struct sock *sk, s64 secs);
 
 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
 
+static inline bool sk_is_readable(struct sock *sk)
+{
+	if (sk->sk_prot->sock_is_readable)
+		return sk->sk_prot->sock_is_readable(sk);
+	return false;
+}
 #endif	/* _SOCK_H */

include/net/tls.h

@@ -375,7 +375,7 @@ void tls_sw_release_resources_rx(struct sock *sk);
 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx);
 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 		   int nonblock, int flags, int *addr_len);
-bool tls_sw_stream_read(const struct sock *sk);
+bool tls_sw_sock_is_readable(struct sock *sk);
 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
 			   struct pipe_inode_info *pipe,
 			   size_t len, unsigned int flags);

net/ipv4/tcp.c

@@ -486,10 +486,7 @@ static bool tcp_stream_is_readable(struct sock *sk, int target)
 {
 	if (tcp_epollin_ready(sk, target))
 		return true;
-
-	if (sk->sk_prot->stream_memory_read)
-		return sk->sk_prot->stream_memory_read(sk);
-	return false;
+	return sk_is_readable(sk);
 }
 
 /*

net/ipv4/tcp_bpf.c

@@ -150,7 +150,7 @@ 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_stream_read(const struct sock *sk)
+static bool tcp_bpf_sock_is_readable(struct sock *sk)
 {
 	struct sk_psock *psock;
 	bool empty = true;
@@ -491,7 +491,7 @@ 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].stream_memory_read	= tcp_bpf_stream_read;
+	prot[TCP_BPF_BASE].sock_is_readable	= tcp_bpf_sock_is_readable;
 
 	prot[TCP_BPF_TX]			= prot[TCP_BPF_BASE];
 	prot[TCP_BPF_TX].sendmsg		= tcp_bpf_sendmsg;

net/tls/tls_main.c

@@ -681,12 +681,12 @@ static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 
 	prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
 	prot[TLS_BASE][TLS_SW].recvmsg		  = tls_sw_recvmsg;
-	prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
+	prot[TLS_BASE][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
 	prot[TLS_BASE][TLS_SW].close		  = tls_sk_proto_close;
 
 	prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
 	prot[TLS_SW][TLS_SW].recvmsg		= tls_sw_recvmsg;
-	prot[TLS_SW][TLS_SW].stream_memory_read	= tls_sw_stream_read;
+	prot[TLS_SW][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
 	prot[TLS_SW][TLS_SW].close		= tls_sk_proto_close;
 
 #ifdef CONFIG_TLS_DEVICE

net/tls/tls_sw.c

@@ -2026,7 +2026,7 @@ splice_read_end:
 	return copied ? : err;
 }
 
-bool tls_sw_stream_read(const struct sock *sk)
+bool tls_sw_sock_is_readable(struct sock *sk)
 {
 	struct tls_context *tls_ctx = tls_get_ctx(sk);
 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);