nl80211: Add generic netlink module alias for cfg80211/nl80211

To support auto-loading of wireless modules from netlink users, add module
alias for nl80211 family.

This also adds NL80211_GENL_NAME constant to define the "nl80211" netlink
family name as part of uapi.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/uapi/linux/nl80211.h

@@ -27,6 +27,8 @@
 
 #include <linux/types.h>
 
+#define NL80211_GENL_NAME "nl80211"
+
 /**
  * DOC: Station handling
  *

net/wireless/core.c

@@ -34,6 +34,7 @@
 MODULE_AUTHOR("Johannes Berg");
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("wireless configuration support");
+MODULE_ALIAS_GENL_FAMILY(NL80211_GENL_NAME);
 
 /* RCU-protected (and cfg80211_mutex for writers) */
 LIST_HEAD(cfg80211_rdev_list);

net/wireless/nl80211.c

@@ -38,7 +38,7 @@ static void nl80211_post_doit(struct genl_ops *ops, struct sk_buff *skb,
 /* the netlink family */
 static struct genl_family nl80211_fam = {
 	.id = GENL_ID_GENERATE,		/* don't bother with a hardcoded ID */
-	.name = "nl80211",	/* have users key off the name instead */
+	.name = NL80211_GENL_NAME,	/* have users key off the name instead */
 	.hdrsize = 0,			/* no private header */
 	.version = 1,			/* no particular meaning now */
 	.maxattr = NL80211_ATTR_MAX,