ipv6: add new struct ipcm6_cookie

In the sendmsg function of UDP, raw, ICMP and l2tp sockets, we use local
variables like hlimits, tclass, opt and dontfrag and pass them to corresponding
functions like ip6_make_skb, ip6_append_data and xxx_push_pending_frames.
This is not a good practice and makes it hard to add new parameters.
This fix introduces a new struct ipcm6_cookie similar to ipcm_cookie in
ipv4 and include the above mentioned variables. And we only pass the
pointer to this structure to corresponding functions. This makes it easier
to add new parameters in the future and makes the function cleaner.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 19 deletions

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index f911c63f79e6..aca06094110f 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1064,11 +1064,9 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	struct ip6_flowlabel *flowlabel = NULL;
 	struct flowi6 fl6;
 	struct dst_entry *dst;
+	struct ipcm6_cookie ipc6;
 	int addr_len = msg->msg_namelen;
 	int ulen = len;
-	int hlimit = -1;
-	int tclass = -1;
-	int dontfrag = -1;
 	int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
 	int err;
 	int connected = 0;
@@ -1076,6 +1074,10 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
 	struct sockcm_cookie sockc;
 
+	ipc6.hlimit = -1;
+	ipc6.tclass = -1;
+	ipc6.dontfrag = -1;
+
 	/* destination address check */
 	if (sin6) {
 		if (addr_len < offsetof(struct sockaddr, sa_data))
@@ -1200,10 +1202,9 @@ do_udp_sendmsg:
 		opt = &opt_space;
 		memset(opt, 0, sizeof(struct ipv6_txoptions));
 		opt->tot_len = sizeof(*opt);
+		ipc6.opt = opt;
 
-		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
-					    &hlimit, &tclass, &dontfrag,
-					    &sockc);
+		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6, &sockc);
 		if (err < 0) {
 			fl6_sock_release(flowlabel);
 			return err;
@@ -1224,6 +1225,7 @@ do_udp_sendmsg:
 	if (flowlabel)
 		opt = fl6_merge_options(&opt_space, flowlabel, opt);
 	opt = ipv6_fixup_options(&opt_space, opt);
+	ipc6.opt = opt;
 
 	fl6.flowi6_proto = sk->sk_protocol;
 	if (!ipv6_addr_any(daddr))
@@ -1253,11 +1255,11 @@ do_udp_sendmsg:
 		goto out;
 	}
 
-	if (hlimit < 0)
-		hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
+	if (ipc6.hlimit < 0)
+		ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 
-	if (tclass < 0)
-		tclass = np->tclass;
+	if (ipc6.tclass < 0)
+		ipc6.tclass = np->tclass;
 
 	if (msg->msg_flags&MSG_CONFIRM)
 		goto do_confirm;
@@ -1268,9 +1270,9 @@ back_from_confirm:
 		struct sk_buff *skb;
 
 		skb = ip6_make_skb(sk, getfrag, msg, ulen,
-				   sizeof(struct udphdr), hlimit, tclass, opt,
+				   sizeof(struct udphdr), &ipc6,
 				   &fl6, (struct rt6_info *)dst,
-				   msg->msg_flags, dontfrag, &sockc);
+				   msg->msg_flags, &sockc);
 		err = PTR_ERR(skb);
 		if (!IS_ERR_OR_NULL(skb))
 			err = udp_v6_send_skb(skb, &fl6);
@@ -1291,14 +1293,12 @@ back_from_confirm:
 	up->pending = AF_INET6;
 
 do_append_data:
-	if (dontfrag < 0)
-		dontfrag = np->dontfrag;
+	if (ipc6.dontfrag < 0)
+		ipc6.dontfrag = np->dontfrag;
 	up->len += ulen;
-	err = ip6_append_data(sk, getfrag, msg, ulen,
-		sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
-		(struct rt6_info *)dst,
-		corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag,
-		&sockc);
+	err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
+			      &ipc6, &fl6, (struct rt6_info *)dst,
+			      corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, &sockc);
 	if (err)
 		udp_v6_flush_pending_frames(sk);
 	else if (!corkreq)