netlink: Export genl_lock() API for use by modules

j-c-h · davem330 · commit f408e0ce4027 · 2010-04-03T14:56:05.000-07:00
This lets kernel modules which use genl netlink APIs serialize netlink
processing.

Signed-off-by: James Chapman &lt;jchapman@katalix.com&gt;
Reviewed-by: Randy Dunlap &lt;randy.dunlap@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git 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
@@ -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)

Original file line number	Diff line number	Diff line change
`@@ -20,15 +20,17 @@`
`20`	`20`
`21`	`21`	`static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */`
`22`	`22`
`23`		`-static inline void genl_lock(void)`
	`23`	`+void genl_lock(void)`
`24`	`24`	`{`
`25`	`25`	`mutex_lock(&genl_mutex);`
`26`	`26`	`}`
	`27`	`+EXPORT_SYMBOL(genl_lock);`
`27`	`28`
`28`		`-static inline void genl_unlock(void)`
	`29`	`+void genl_unlock(void)`
`29`	`30`	`{`
`30`	`31`	`mutex_unlock(&genl_mutex);`
`31`	`32`	`}`
	`33`	`+EXPORT_SYMBOL(genl_unlock);`
`32`	`34`
`33`	`35`	`#define GENL_FAM_TAB_SIZE 16`
`34`	`36`	`#define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1)`