datapath: omit _mod from module names

[sliver-openvswitch.git] / datapath / compat.h

diff --git a/datapath/compat.h b/datapath/compat.h
index efad6a0..71fa06c 100644 (file)
--- a/datapath/compat.h
+++ b/datapath/compat.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007-2011 Nicira Networks.
+ * Copyright (c) 2007-2012 Nicira Networks.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of version 2 of the GNU General Public
@@ -53,4 +53,32 @@ static inline void skb_clear_rxhash(struct sk_buff *skb)
 #endif
 }
 
+/*
+ * Enforces, mutual exclusion with the Linux bridge module, by declaring and
+ * exporting br_should_route_hook.  Because the bridge module also exports the
+ * same symbol, the module loader will refuse to load both modules at the same
+ * time (e.g. "bridge: exports duplicate symbol br_should_route_hook (owned by
+ * openvswitch)").
+ *
+ * Before Linux 2.6.36, Open vSwitch cannot safely coexist with the Linux
+ * bridge module, so openvswitch uses this macro in those versions.  In
+ * Linux 2.6.36 and later, Open vSwitch can coexist with the bridge module,
+ * but it makes no sense to load both bridge and brcompat, so brcompat uses
+ * this macro in those versions.
+ *
+ * The use of "typeof" here avoids the need to track changes in the type of
+ * br_should_route_hook over various kernel versions.
+ */
+#define BRIDGE_MUTUAL_EXCLUSION                                        \
+       typeof(br_should_route_hook) br_should_route_hook;      \
+       EXPORT_SYMBOL(br_should_route_hook)
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
+#define GENL_SOCK(net) (genl_sock)
+#define SET_NETNSOK
+#else
+#define GENL_SOCK(net) ((net)->genl_sock)
+#define SET_NETNSOK    .netnsok = true,
+#endif
+
 #endif /* compat.h */