headers/deps: net: Introduce <net/sock_api_extra.h> for rarely used APIs

Move the sk*backlog() functionality over there - it's only used in
~25 files, while <net/sock_api.h> is included in over 1,000 files
on an typical distro kernel build.

The motivation is to decouple <net/sock_api.h> from <net/dst_api.h>
some more, paving the way for more header dependency reductions.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 70 insertions, 64 deletions

diff --git a/include/net/sock_api.h b/include/net/sock_api.h
index 4386fc80c43902..d78bd655ddff49 100644
--- a/include/net/sock_api.h
+++ b/include/net/sock_api.h
@@ -474,69 +474,6 @@ static inline void sk_wmem_queued_add(struct sock *sk, int val)
 
 void sk_stream_write_space(struct sock *sk);
 
-/* OOB backlog add */
-static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
-{
-	/* dont let skb dst not refcounted, we are going to leave rcu lock */
-	skb_dst_force(skb);
-
-	if (!sk->sk_backlog.tail)
-		WRITE_ONCE(sk->sk_backlog.head, skb);
-	else
-		sk->sk_backlog.tail->next = skb;
-
-	WRITE_ONCE(sk->sk_backlog.tail, skb);
-	skb->next = NULL;
-}
-
-/*
- * Take into account size of receive queue and backlog queue
- * Do not take into account this skb truesize,
- * to allow even a single big packet to come.
- */
-static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
-{
-	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
-
-	return qsize > limit;
-}
-
-/* The per-socket spinlock must be held here. */
-static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
-					      unsigned int limit)
-{
-	if (sk_rcvqueues_full(sk, limit))
-		return -ENOBUFS;
-
-	/*
-	 * If the skb was allocated from pfmemalloc reserves, only
-	 * allow SOCK_MEMALLOC sockets to use it as this socket is
-	 * helping free memory
-	 */
-	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
-		return -ENOMEM;
-
-	__sk_add_backlog(sk, skb);
-	sk->sk_backlog.len += skb->truesize;
-	return 0;
-}
-
-int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
-
-INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
-INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
-
-static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
-{
-	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
-		return __sk_backlog_rcv(sk, skb);
-
-	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
-				  tcp_v6_do_rcv,
-				  tcp_v4_do_rcv,
-				  sk, skb);
-}
-
 static inline void sk_incoming_cpu_update(struct sock *sk)
 {
 	int cpu = raw_smp_processor_id();
diff --git a/include/net/sock_api_extra.h b/include/net/sock_api_extra.h
index f7e055489e6700..349210c624f671 100644
--- a/include/net/sock_api_extra.h
+++ b/include/net/sock_api_extra.h
@@ -1 +1,70 @@
-#include <net/sock.h>
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _SOCK_API_EXTRA_H
+#define _SOCK_API_EXTRA_H
+
+#include <net/sock_api.h>
+
+/* OOB backlog add */
+static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
+{
+	/* dont let skb dst not refcounted, we are going to leave rcu lock */
+	skb_dst_force(skb);
+
+	if (!sk->sk_backlog.tail)
+		WRITE_ONCE(sk->sk_backlog.head, skb);
+	else
+		sk->sk_backlog.tail->next = skb;
+
+	WRITE_ONCE(sk->sk_backlog.tail, skb);
+	skb->next = NULL;
+}
+
+/*
+ * Take into account size of receive queue and backlog queue
+ * Do not take into account this skb truesize,
+ * to allow even a single big packet to come.
+ */
+static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
+{
+	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
+
+	return qsize > limit;
+}
+
+/* The per-socket spinlock must be held here. */
+static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
+					      unsigned int limit)
+{
+	if (sk_rcvqueues_full(sk, limit))
+		return -ENOBUFS;
+
+	/*
+	 * If the skb was allocated from pfmemalloc reserves, only
+	 * allow SOCK_MEMALLOC sockets to use it as this socket is
+	 * helping free memory
+	 */
+	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
+		return -ENOMEM;
+
+	__sk_add_backlog(sk, skb);
+	sk->sk_backlog.len += skb->truesize;
+	return 0;
+}
+
+int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
+
+INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
+INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
+
+static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
+{
+	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
+		return __sk_backlog_rcv(sk, skb);
+
+	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
+				  tcp_v6_do_rcv,
+				  tcp_v4_do_rcv,
+				  sk, skb);
+}
+
+#endif	/* _SOCK_API_EXTRA_H */