[XFRM]: Define packet dropping statistics.

This statistics is shown factor dropped by transformation
at /proc/net/xfrm_stat for developer.
It is a counter designed from current transformation source code
and defined as linux private MIB.

See Documentation/networking/xfrm_proc.txt for the detail.

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 0 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index eea1c327c93e..a79702bcdcd0 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -19,6 +19,9 @@
 #include <net/route.h>
 #include <net/ipv6.h>
 #include <net/ip6_fib.h>
+#ifdef CONFIG_XFRM_STATISTICS
+#include <net/snmp.h>
+#endif
 
 #define XFRM_PROTO_ESP          50
 #define XFRM_PROTO_AH           51
@@ -34,6 +37,17 @@
 #define MODULE_ALIAS_XFRM_TYPE(family, proto) \
         MODULE_ALIAS("xfrm-type-" __stringify(family) "-" __stringify(proto))
 
+#ifdef CONFIG_XFRM_STATISTICS
+DECLARE_SNMP_STAT(struct linux_xfrm_mib, xfrm_statistics);
+#define XFRM_INC_STATS(field)           SNMP_INC_STATS(xfrm_statistics, field)
+#define XFRM_INC_STATS_BH(field)        SNMP_INC_STATS_BH(xfrm_statistics, field)
+#define XFRM_INC_STATS_USER(field)      SNMP_INC_STATS_USER(xfrm_statistics, field)
+#else
+#define XFRM_INC_STATS(field)
+#define XFRM_INC_STATS_BH(field)
+#define XFRM_INC_STATS_USER(field)
+#endif
+
 extern struct sock *xfrm_nl;
 extern u32 sysctl_xfrm_aevent_etime;
 extern u32 sysctl_xfrm_aevent_rseqth;
@@ -1139,6 +1153,10 @@ static inline void xfrm6_fini(void)
 }
 #endif
 
+#ifdef CONFIG_XFRM_STATISTICS
+extern int xfrm_proc_init(void);
+#endif
+
 extern int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*), void *);
 extern struct xfrm_state *xfrm_state_alloc(void);
 extern struct xfrm_state *xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,