ipv6: ioam: Prerequisite patch for ioam6_iptunnel

This prerequisite patch provides some minor edits (alignments, renames) and a
minor modification inside a function to facilitate the next patch by using
existing nla_* functions.
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ioam6_iptunnel.c

@@ -9,7 +9,6 @@
 #include <linux/kernel.h>
 #include <linux/skbuff.h>
 #include <linux/net.h>
-#include <linux/netlink.h>
 #include <linux/in6.h>
 #include <linux/ioam6.h>
 #include <linux/ioam6_iptunnel.h>
@@ -17,15 +16,16 @@
 #include <net/sock.h>
 #include <net/lwtunnel.h>
 #include <net/ioam6.h>
+#include <net/netlink.h>
 
 #define IOAM6_MASK_SHORT_FIELDS 0xff100000
 #define IOAM6_MASK_WIDE_FIELDS 0xe00000
 
 struct ioam6_lwt_encap {
-	struct ipv6_hopopt_hdr	eh;
-	u8			pad[2];	/* 2-octet padding for 4n-alignment */
-	struct ioam6_hdr	ioamh;
-	struct ioam6_trace_hdr	traceh;
+	struct ipv6_hopopt_hdr eh;
+	u8 pad[2];			/* 2-octet padding for 4n-alignment */
+	struct ioam6_hdr ioamh;
+	struct ioam6_trace_hdr traceh;
 } __packed;
 
 struct ioam6_lwt {
@@ -42,7 +42,7 @@ static struct ioam6_lwt_encap *ioam6_lwt_info(struct lwtunnel_state *lwt)
 	return &ioam6_lwt_state(lwt)->tuninfo;
 }
 
-static struct ioam6_trace_hdr *ioam6_trace(struct lwtunnel_state *lwt)
+static struct ioam6_trace_hdr *ioam6_lwt_trace(struct lwtunnel_state *lwt)
 {
 	return &(ioam6_lwt_state(lwt)->tuninfo.traceh);
 }
@@ -51,25 +51,6 @@ static const struct nla_policy ioam6_iptunnel_policy[IOAM6_IPTUNNEL_MAX + 1] = {
 	[IOAM6_IPTUNNEL_TRACE]	= NLA_POLICY_EXACT_LEN(sizeof(struct ioam6_trace_hdr)),
 };
 
-static int nla_put_ioam6_trace(struct sk_buff *skb, int attrtype,
-			       struct ioam6_trace_hdr *trace)
-{
-	struct ioam6_trace_hdr *data;
-	struct nlattr *nla;
-	int len;
-
-	len = sizeof(*trace);
-
-	nla = nla_reserve(skb, attrtype, len);
-	if (!nla)
-		return -EMSGSIZE;
-
-	data = nla_data(nla);
-	memcpy(data, trace, len);
-
-	return 0;
-}
-
 static bool ioam6_validate_trace_hdr(struct ioam6_trace_hdr *trace)
 {
 	u32 fields;
@@ -231,36 +212,40 @@ static int ioam6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 static int ioam6_fill_encap_info(struct sk_buff *skb,
 				 struct lwtunnel_state *lwtstate)
 {
-	struct ioam6_trace_hdr *trace = ioam6_trace(lwtstate);
+	struct ioam6_trace_hdr *trace;
+	int err;
 
-	if (nla_put_ioam6_trace(skb, IOAM6_IPTUNNEL_TRACE, trace))
-		return -EMSGSIZE;
+	trace = ioam6_lwt_trace(lwtstate);
+
+	err = nla_put(skb, IOAM6_IPTUNNEL_TRACE, sizeof(*trace), trace);
+	if (err)
+		return err;
 
 	return 0;
 }
 
 static int ioam6_encap_nlsize(struct lwtunnel_state *lwtstate)
 {
-	struct ioam6_trace_hdr *trace = ioam6_trace(lwtstate);
+	struct ioam6_trace_hdr *trace = ioam6_lwt_trace(lwtstate);
 
 	return nla_total_size(sizeof(*trace));
 }
 
 static int ioam6_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
 {
-	struct ioam6_trace_hdr *a_hdr = ioam6_trace(a);
-	struct ioam6_trace_hdr *b_hdr = ioam6_trace(b);
+	struct ioam6_trace_hdr *a_hdr = ioam6_lwt_trace(a);
+	struct ioam6_trace_hdr *b_hdr = ioam6_lwt_trace(b);
 
 	return (a_hdr->namespace_id != b_hdr->namespace_id);
 }
 
 static const struct lwtunnel_encap_ops ioam6_iptun_ops = {
-	.build_state	= ioam6_build_state,
+	.build_state		= ioam6_build_state,
 	.output		= ioam6_output,
-	.fill_encap	= ioam6_fill_encap_info,
+	.fill_encap		= ioam6_fill_encap_info,
 	.get_encap_size	= ioam6_encap_nlsize,
-	.cmp_encap	= ioam6_encap_cmp,
-	.owner		= THIS_MODULE,
+	.cmp_encap		= ioam6_encap_cmp,
+	.owner			= THIS_MODULE,
 };
 
 int __init ioam6_iptunnel_init(void)