1 files changed, 67 insertions, 0 deletions
diff --git a/include/net/dst_ops.h b/include/net/dst_ops.h
new file mode 100644
index 00000000..dc074632
--- /dev/null
+++ b/include/net/dst_ops.h
@@ -0,0 +1,67 @@
+#ifndef _NET_DST_OPS_H
+#define _NET_DST_OPS_H
+#include <linux/types.h>
+#include <linux/percpu_counter.h>
+#include <linux/cache.h>
+
+struct dst_entry;
+struct kmem_cachep;
+struct net_device;
+struct sk_buff;
+
+struct dst_ops {
+	unsigned short		family;
+	__be16			protocol;
+	unsigned		gc_thresh;
+
+	int			(*gc)(struct dst_ops *ops);
+	struct dst_entry *	(*check)(struct dst_entry *, __u32 cookie);
+	unsigned int		(*default_advmss)(const struct dst_entry *);
+	unsigned int		(*default_mtu)(const struct dst_entry *);
+	u32 *			(*cow_metrics)(struct dst_entry *, unsigned long);
+	void			(*destroy)(struct dst_entry *);
+	void			(*ifdown)(struct dst_entry *,
+					  struct net_device *dev, int how);
+	struct dst_entry *	(*negative_advice)(struct dst_entry *);
+	void			(*link_failure)(struct sk_buff *);
+	void			(*update_pmtu)(struct dst_entry *dst, u32 mtu);
+	int			(*local_out)(struct sk_buff *skb);
+
+	struct kmem_cache	*kmem_cachep;
+
+	struct percpu_counter	pcpuc_entries ____cacheline_aligned_in_smp;
+};
+
+static inline int dst_entries_get_fast(struct dst_ops *dst)
+{
+	return percpu_counter_read_positive(&dst->pcpuc_entries);
+}
+
+static inline int dst_entries_get_slow(struct dst_ops *dst)
+{
+	int res;
+
+	local_bh_disable();
+	res = percpu_counter_sum_positive(&dst->pcpuc_entries);
+	local_bh_enable();
+	return res;
+}
+
+static inline void dst_entries_add(struct dst_ops *dst, int val)
+{
+	local_bh_disable();
+	percpu_counter_add(&dst->pcpuc_entries, val);
+	local_bh_enable();
+}
+
+static inline int dst_entries_init(struct dst_ops *dst)
+{
+	return percpu_counter_init(&dst->pcpuc_entries, 0);
+}
+
+static inline void dst_entries_destroy(struct dst_ops *dst)
+{
+	percpu_counter_destroy(&dst->pcpuc_entries);
+}
+
+#endif