[PATCH v3 08/12] netlink: Export genl_lock() API for use by modules

[James Chapman <jchapman@katalix.com>]

This lets kernel modules which use genl netlink APIs serialize netlink
processing.

Signed-off-by: James Chapman <jchapman@katalix.com>
Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com>
---
 include/linux/genetlink.h |    8 ++++++++
 net/netlink/genetlink.c   |    6 ++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/include/linux/genetlink.h b/include/linux/genetlink.h
index b834ef6..61549b2 100644
--- a/include/linux/genetlink.h
+++ b/include/linux/genetlink.h
@@ -80,4 +80,12 @@ enum {
 
 #define CTRL_ATTR_MCAST_GRP_MAX (__CTRL_ATTR_MCAST_GRP_MAX - 1)
 
+#ifdef __KERNEL__
+
+/* All generic netlink requests are serialized by a global lock.  */
+extern void genl_lock(void);
+extern void genl_unlock(void);
+
+#endif /* __KERNEL__ */
+
 #endif	/* __LINUX_GENERIC_NETLINK_H */
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index a4b6e14..a28fda7 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -20,15 +20,17 @@
 
 static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */
 
-static inline void genl_lock(void)
+void genl_lock(void)
 {
 	mutex_lock(&genl_mutex);
 }
+EXPORT_SYMBOL(genl_lock);
 
-static inline void genl_unlock(void)
+void genl_unlock(void)
 {
 	mutex_unlock(&genl_mutex);
 }
+EXPORT_SYMBOL(genl_unlock);
 
 #define GENL_FAM_TAB_SIZE	16
 #define GENL_FAM_TAB_MASK	(GENL_FAM_TAB_SIZE - 1)