[PATCH] Add genetlink utilities for payload length calculation

Add two utility helper functions genlmsg_msg_size() and genlmsg_total_size().
These functions are derived from their netlink counterparts.

Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jamal Hadi <hadi@cyberus.ca>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/net/genetlink.h

@@ -169,4 +169,22 @@ static inline int genlmsg_len(const struct genlmsghdr *gnlh)
 	return (nlh->nlmsg_len - GENL_HDRLEN - NLMSG_HDRLEN);
 }
 
+/**
+ * genlmsg_msg_size - length of genetlink message not including padding
+ * @payload: length of message payload
+ */
+static inline int genlmsg_msg_size(int payload)
+{
+	return GENL_HDRLEN + payload;
+}
+
+/**
+ * genlmsg_total_size - length of genetlink message including padding
+ * @payload: length of message payload
+ */
+static inline int genlmsg_total_size(int payload)
+{
+	return NLMSG_ALIGN(genlmsg_msg_size(payload));
+}
+
 #endif	/* __NET_GENERIC_NETLINK_H */