[PATCH V2 net-next 01/15] net: introduce keepalive function in struct proto

[Ursula Braun <ubraun@linux.vnet.ibm.com>]

Direct call of tcp_set_keepalive() function from protocol-agnostic
sock_setsockopt() function in net/core/sock.c violates network
layering. And newly introduced protocol (SMC-R) will need its own
keepalive function. Therefore, add "keepalive" function pointer
to "struct proto", and call it from sock_setsockopt() via this pointer.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Utz Bacher <utz.bacher@de.ibm.com>
---
 include/net/sock.h   | 1 +
 net/core/sock.c      | 7 ++-----
 net/ipv4/tcp_ipv4.c  | 1 +
 net/ipv4/tcp_timer.c | 1 +
 net/ipv6/tcp_ipv6.c  | 1 +
 5 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/net/sock.h b/include/net/sock.h
index ebf75db..474e89f 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -988,6 +988,7 @@ struct proto {
 	int			(*getsockopt)(struct sock *sk, int level,
 					int optname, char __user *optval,
 					int __user *option);
+	void			(*keepalive)(struct sock *sk, int valbool);
 #ifdef CONFIG_COMPAT
 	int			(*compat_setsockopt)(struct sock *sk,
 					int level,
diff --git a/net/core/sock.c b/net/core/sock.c
index 038e660..ce31244 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -761,11 +761,8 @@ set_rcvbuf:
 		goto set_rcvbuf;
 
 	case SO_KEEPALIVE:
-#ifdef CONFIG_INET
-		if (sk->sk_protocol == IPPROTO_TCP &&
-		    sk->sk_type == SOCK_STREAM)
-			tcp_set_keepalive(sk, valbool);
-#endif
+		if (sk->sk_prot->keepalive)
+			sk->sk_prot->keepalive(sk, valbool);
 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
 		break;
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 7ac37c3..a7ddb16 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2361,6 +2361,7 @@ struct proto tcp_prot = {
 	.shutdown		= tcp_shutdown,
 	.setsockopt		= tcp_setsockopt,
 	.getsockopt		= tcp_getsockopt,
+	.keepalive		= tcp_set_keepalive,
 	.recvmsg		= tcp_recvmsg,
 	.sendmsg		= tcp_sendmsg,
 	.sendpage		= tcp_sendpage,
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index f712b41..abb1ea1 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -613,6 +613,7 @@ void tcp_set_keepalive(struct sock *sk, int val)
 	else if (!val)
 		inet_csk_delete_keepalive_timer(sk);
 }
+EXPORT_SYMBOL(tcp_set_keepalive);
 
 
 static void tcp_keepalive_timer (unsigned long data)
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 54cf719..a4ea411 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1876,6 +1876,7 @@ struct proto tcpv6_prot = {
 	.shutdown		= tcp_shutdown,
 	.setsockopt		= tcp_setsockopt,
 	.getsockopt		= tcp_getsockopt,
+	.keepalive		= tcp_set_keepalive,
 	.recvmsg		= tcp_recvmsg,
 	.sendmsg		= tcp_sendmsg,
 	.sendpage		= tcp_sendpage,
-- 
2.8.4