[PATCH bpf-next v7 1/6] ipv6: sr: make seg6.h includable without IPv6

[Mathieu Xhonneux <m.xhonneux@gmail.com>]

include/net/seg6.h cannot be included in a source file if CONFIG_IPV6 is
not enabled:
   include/net/seg6.h: In function 'seg6_pernet':
>> include/net/seg6.h:52:14: error: 'struct net' has no member named
                                        'ipv6'; did you mean 'ipv4'?
     return net->ipv6.seg6_data;
                 ^~~~
                 ipv4

This commit makes seg6_pernet return NULL if IPv6 is not compiled, hence
allowing seg6.h to be included regardless of the configuration.

Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com>
---
 include/net/seg6.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/net/seg6.h b/include/net/seg6.h
index 099bad59dc90..70b4cfac52d7 100644
--- a/include/net/seg6.h
+++ b/include/net/seg6.h
@@ -49,7 +49,11 @@ struct seg6_pernet_data {
 
 static inline struct seg6_pernet_data *seg6_pernet(struct net *net)
 {
+#if IS_ENABLED(CONFIG_IPV6)
 	return net->ipv6.seg6_data;
+#else
+	return NULL;
+#endif
 }
 
 extern int seg6_init(void);
-- 
2.16.1