ip: IP cmsg cleanup

Move the IP_CMSG_* constants from ip_sockglue.c to inet_sock.h so that
they can be referenced in other source files.

Restructure ip_cmsg_recv to not go through flags using shift, check
for flags by 'and'. This eliminates both the shift and a conditional
per flag check.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 360b110..605ca42 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -16,7 +16,7 @@
 #ifndef _INET_SOCK_H
 #define _INET_SOCK_H
 
-
+#include <linux/bitops.h>
 #include <linux/kmemcheck.h>
 #include <linux/string.h>
 #include <linux/types.h>
@@ -195,6 +195,15 @@
 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
 
+/* cmsg flags for inet */
+#define IP_CMSG_PKTINFO		BIT(0)
+#define IP_CMSG_TTL		BIT(1)
+#define IP_CMSG_TOS		BIT(2)
+#define IP_CMSG_RECVOPTS	BIT(3)
+#define IP_CMSG_RETOPTS		BIT(4)
+#define IP_CMSG_PASSSEC		BIT(5)
+#define IP_CMSG_ORIGDSTADDR	BIT(6)
+
 static inline struct inet_sock *inet_sk(const struct sock *sk)
 {
 	return (struct inet_sock *)sk;