nlattr: Fix build error with NET off

We moved the netlink attribute support from net to lib in order
for it to be available for general consumption.  However, parts
of the code (the bits that we don't need :) really depends on
NET because the target object is sk_buff.

This patch fixes this by wrapping them in CONFIG_NET.

Some EXPORTs have been moved to make this work.
Tested-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

lib/nlattr.c

@@ -281,6 +281,7 @@ int nla_strcmp(const struct nlattr *nla, const char *str)
 	return d;
 }
 
+#ifdef CONFIG_NET
 /**
  * __nla_reserve - reserve room for attribute on the skb
  * @skb: socket buffer to reserve room on
@@ -305,6 +306,7 @@ struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
 
 	return nla;
 }
+EXPORT_SYMBOL(__nla_reserve);
 
 /**
  * __nla_reserve_nohdr - reserve room for attribute without header
@@ -325,6 +327,7 @@ void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
 
 	return start;
 }
+EXPORT_SYMBOL(__nla_reserve_nohdr);
 
 /**
  * nla_reserve - reserve room for attribute on the skb
@@ -345,6 +348,7 @@ struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
 
 	return __nla_reserve(skb, attrtype, attrlen);
 }
+EXPORT_SYMBOL(nla_reserve);
 
 /**
  * nla_reserve_nohdr - reserve room for attribute without header
@@ -363,6 +367,7 @@ void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
 
 	return __nla_reserve_nohdr(skb, attrlen);
 }
+EXPORT_SYMBOL(nla_reserve_nohdr);
 
 /**
  * __nla_put - Add a netlink attribute to a socket buffer
@@ -382,6 +387,7 @@ void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
 	nla = __nla_reserve(skb, attrtype, attrlen);
 	memcpy(nla_data(nla), data, attrlen);
 }
+EXPORT_SYMBOL(__nla_put);
 
 /**
  * __nla_put_nohdr - Add a netlink attribute without header
@@ -399,6 +405,7 @@ void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
 	start = __nla_reserve_nohdr(skb, attrlen);
 	memcpy(start, data, attrlen);
 }
+EXPORT_SYMBOL(__nla_put_nohdr);
 
 /**
  * nla_put - Add a netlink attribute to a socket buffer
@@ -418,6 +425,7 @@ int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
 	__nla_put(skb, attrtype, attrlen, data);
 	return 0;
 }
+EXPORT_SYMBOL(nla_put);
 
 /**
  * nla_put_nohdr - Add a netlink attribute without header
@@ -436,6 +444,7 @@ int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
 	__nla_put_nohdr(skb, attrlen, data);
 	return 0;
 }
+EXPORT_SYMBOL(nla_put_nohdr);
 
 /**
  * nla_append - Add a netlink attribute without header or padding
@@ -454,20 +463,13 @@ int nla_append(struct sk_buff *skb, int attrlen, const void *data)
 	memcpy(skb_put(skb, attrlen), data, attrlen);
 	return 0;
 }
+EXPORT_SYMBOL(nla_append);
+#endif
 
 EXPORT_SYMBOL(nla_validate);
 EXPORT_SYMBOL(nla_parse);
 EXPORT_SYMBOL(nla_find);
 EXPORT_SYMBOL(nla_strlcpy);
-EXPORT_SYMBOL(__nla_reserve);
-EXPORT_SYMBOL(__nla_reserve_nohdr);
-EXPORT_SYMBOL(nla_reserve);
-EXPORT_SYMBOL(nla_reserve_nohdr);
-EXPORT_SYMBOL(__nla_put);
-EXPORT_SYMBOL(__nla_put_nohdr);
-EXPORT_SYMBOL(nla_put);
-EXPORT_SYMBOL(nla_put_nohdr);
 EXPORT_SYMBOL(nla_memcpy);
 EXPORT_SYMBOL(nla_memcmp);
 EXPORT_SYMBOL(nla_strcmp);
-EXPORT_SYMBOL(nla_append);