[PATCH net-next 1/4] gro: make net/gro.h self-contained

[Alexander Lobakin <alobakin@pm.me>]

If some source file includes <net/gro.h>, but doesn't include
<linux/indirect_call_wrapper.h>:

In file included from net/8021q/vlan_core.c:7:
./include/net/gro.h:6:1: warning: data definition has no type or storage class
    6 | INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *,
      | ^~~~~~~~~~~~~~~~~~~~~~~~~
./include/net/gro.h:6:1: error: type defaults to ‘int’ in declaration of ‘INDIRECT_CALLABLE_DECLARE’ [-Werror=implicit-int]

[...]

Include <linux/indirect_call_wrapper.h> directly. It's small and
won't pull lots of dependencies.
Also add some incomplete struct declarations to be fully stacked.

Fixes: 04f00ab2275f ("net/core: move gro function declarations to separate header ")
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
---
 include/net/gro.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/net/gro.h b/include/net/gro.h
index 8a6eb5303cc4..27c38b36df16 100644
--- a/include/net/gro.h
+++ b/include/net/gro.h
@@ -3,6 +3,11 @@
 #ifndef _NET_IPV6_GRO_H
 #define _NET_IPV6_GRO_H

+#include <linux/indirect_call_wrapper.h>
+
+struct list_head;
+struct sk_buff;
+
 INDIRECT_CALLABLE_DECLARE(struct sk_buff *ipv6_gro_receive(struct list_head *,
 							   struct sk_buff *));
 INDIRECT_CALLABLE_DECLARE(int ipv6_gro_complete(struct sk_buff *, int));
--
2.31.0