1 files changed, 174 insertions, 0 deletions
diff --git a/include/net/inetpeer.h b/include/net/inetpeer.h
new file mode 100644
index 000000000..d5332ddce
--- /dev/null
+++ b/include/net/inetpeer.h
@@ -0,0 +1,174 @@
+/*
+ *		INETPEER - A storage for permanent information about peers
+ *
+ *  Authors:	Andrey V. Savochkin <saw@msu.ru>
+ */
+
+#ifndef _NET_INETPEER_H
+#define _NET_INETPEER_H
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/spinlock.h>
+#include <linux/rtnetlink.h>
+#include <net/ipv6.h>
+#include <linux/atomic.h>
+
+struct inetpeer_addr_base {
+	union {
+		__be32			a4;
+		__be32			a6[4];
+		struct in6_addr		in6;
+	};
+};
+
+struct inetpeer_addr {
+	struct inetpeer_addr_base	addr;
+	__u16				family;
+};
+
+struct inet_peer {
+	/* group together avl_left,avl_right,v4daddr to speedup lookups */
+	struct inet_peer __rcu	*avl_left, *avl_right;
+	struct inetpeer_addr	daddr;
+	__u32			avl_height;
+
+	u32			metrics[RTAX_MAX];
+	u32			rate_tokens;	/* rate limiting for ICMP */
+	unsigned long		rate_last;
+	union {
+		struct list_head	gc_list;
+		struct rcu_head     gc_rcu;
+	};
+	/*
+	 * Once inet_peer is queued for deletion (refcnt == -1), following field
+	 * is not available: rid
+	 * We can share memory with rcu_head to help keep inet_peer small.
+	 */
+	union {
+		struct {
+			atomic_t			rid;		/* Frag reception counter */
+		};
+		struct rcu_head         rcu;
+		struct inet_peer	*gc_next;
+	};
+
+	/* following fields might be frequently dirtied */
+	__u32			dtime;	/* the time of last use of not referenced entries */
+	atomic_t		refcnt;
+};
+
+struct inet_peer_base {
+	struct inet_peer __rcu	*root;
+	seqlock_t		lock;
+	int			total;
+};
+
+#define INETPEER_BASE_BIT	0x1UL
+
+static inline struct inet_peer *inetpeer_ptr(unsigned long val)
+{
+	BUG_ON(val & INETPEER_BASE_BIT);
+	return (struct inet_peer *) val;
+}
+
+static inline struct inet_peer_base *inetpeer_base_ptr(unsigned long val)
+{
+	if (!(val & INETPEER_BASE_BIT))
+		return NULL;
+	val &= ~INETPEER_BASE_BIT;
+	return (struct inet_peer_base *) val;
+}
+
+static inline bool inetpeer_ptr_is_peer(unsigned long val)
+{
+	return !(val & INETPEER_BASE_BIT);
+}
+
+static inline void __inetpeer_ptr_set_peer(unsigned long *val, struct inet_peer *peer)
+{
+	/* This implicitly clears INETPEER_BASE_BIT */
+	*val = (unsigned long) peer;
+}
+
+static inline bool inetpeer_ptr_set_peer(unsigned long *ptr, struct inet_peer *peer)
+{
+	unsigned long val = (unsigned long) peer;
+	unsigned long orig = *ptr;
+
+	if (!(orig & INETPEER_BASE_BIT) ||
+	    cmpxchg(ptr, orig, val) != orig)
+		return false;
+	return true;
+}
+
+static inline void inetpeer_init_ptr(unsigned long *ptr, struct inet_peer_base *base)
+{
+	*ptr = (unsigned long) base | INETPEER_BASE_BIT;
+}
+
+static inline void inetpeer_transfer_peer(unsigned long *to, unsigned long *from)
+{
+	unsigned long val = *from;
+
+	*to = val;
+	if (inetpeer_ptr_is_peer(val)) {
+		struct inet_peer *peer = inetpeer_ptr(val);
+		atomic_inc(&peer->refcnt);
+	}
+}
+
+void inet_peer_base_init(struct inet_peer_base *);
+
+void inet_initpeers(void) __init;
+
+#define INETPEER_METRICS_NEW	(~(u32) 0)
+
+static inline bool inet_metrics_new(const struct inet_peer *p)
+{
+	return p->metrics[RTAX_LOCK-1] == INETPEER_METRICS_NEW;
+}
+
+/* can be called with or without local BH being disabled */
+struct inet_peer *inet_getpeer(struct inet_peer_base *base,
+			       const struct inetpeer_addr *daddr,
+			       int create);
+
+static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
+						__be32 v4daddr,
+						int create)
+{
+	struct inetpeer_addr daddr;
+
+	daddr.addr.a4 = v4daddr;
+	daddr.family = AF_INET;
+	return inet_getpeer(base, &daddr, create);
+}
+
+static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
+						const struct in6_addr *v6daddr,
+						int create)
+{
+	struct inetpeer_addr daddr;
+
+	daddr.addr.in6 = *v6daddr;
+	daddr.family = AF_INET6;
+	return inet_getpeer(base, &daddr, create);
+}
+
+/* can be called from BH context or outside */
+void inet_putpeer(struct inet_peer *p);
+bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
+
+void inetpeer_invalidate_tree(struct inet_peer_base *);
+
+/*
+ * temporary check to make sure we dont access rid, tcp_ts,
+ * tcp_ts_stamp if no refcount is taken on inet_peer
+ */
+static inline void inet_peer_refcheck(const struct inet_peer *p)
+{
+	WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
+}
+#endif /* _NET_INETPEER_H */