[linux-2.6-block.git] / include / net / inetpeer.h

/*
 *		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 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;

	*(struct in6_addr *)daddr.addr.a6 = *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 */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* INETPEER - A storage for permanent information about peers
	3	*
1da177e4 LT	4	* Authors: Andrey V. Savochkin <saw@msu.ru>
	5	*/
	6
	7	#ifndef _NET_INETPEER_H
	8	#define _NET_INETPEER_H
	9
	10	#include <linux/types.h>
	11	#include <linux/init.h>
	12	#include <linux/jiffies.h>
	13	#include <linux/spinlock.h>
60659823	14	#include <linux/rtnetlink.h>
672f007d	15	#include <net/ipv6.h>
60063497	16	#include <linux/atomic.h>
1da177e4	17
7a71ed89	18	struct inetpeer_addr_base {
582a72da	19	union {
7a71ed89 DM	20	__be32 a4;
7a71ed89 DM	21	__be32 a6[4];
582a72da	22	};
7a71ed89 DM	23	};
	24
	25	struct inetpeer_addr {
	26	struct inetpeer_addr_base addr;
	27	__u16 family;
8790ca17	28	};
582a72da	29
fd2c3ef7	30	struct inet_peer {
78d79423	31	/* group together avl_left,avl_right,v4daddr to speedup lookups */
b914c4ea	32	struct inet_peer __rcu avl_left, avl_right;
8790ca17	33	struct inetpeer_addr daddr;
2c1409a0	34	__u32 avl_height;
2b77bdde ED	35
	36	u32 metrics[RTAX_MAX];
	37	u32 rate_tokens; /* rate limiting for ICMP */
	38	unsigned long rate_last;
55432d2b ED	39	union {
	40	struct list_head gc_list;
	41	struct rcu_head gc_rcu;
	42	};
317fe0e6	43	/*
73f156a6 ED	44	* Once inet_peer is queued for deletion (refcnt == -1), following field
73f156a6 ED	45	* is not available: rid
60659823	46	* We can share memory with rcu_head to help keep inet_peer small.
317fe0e6 ED	47	*/
	48	union {
	49	struct {
ddd4aa42	50	atomic_t rid; /* Frag reception counter */
317fe0e6 ED	51	};
317fe0e6 ED	52	struct rcu_head rcu;
4b9d9be8	53	struct inet_peer *gc_next;
317fe0e6	54	};
2b77bdde ED	55
	56	/* following fields might be frequently dirtied */
	57	__u32 dtime; /* the time of last use of not referenced entries */
	58	atomic_t refcnt;
1da177e4 LT	59	};
1da177e4 LT	60
c3426b47 DM	61	struct inet_peer_base {
	62	struct inet_peer __rcu *root;
	63	seqlock_t lock;
	64	int total;
	65	};
	66
97bab73f DM	67	#define INETPEER_BASE_BIT 0x1UL
	68
	69	static inline struct inet_peer *inetpeer_ptr(unsigned long val)
	70	{
	71	BUG_ON(val & INETPEER_BASE_BIT);
	72	return (struct inet_peer *) val;
	73	}
	74
	75	static inline struct inet_peer_base *inetpeer_base_ptr(unsigned long val)
	76	{
	77	if (!(val & INETPEER_BASE_BIT))
	78	return NULL;
	79	val &= ~INETPEER_BASE_BIT;
	80	return (struct inet_peer_base *) val;
	81	}
	82
	83	static inline bool inetpeer_ptr_is_peer(unsigned long val)
	84	{
	85	return !(val & INETPEER_BASE_BIT);
	86	}
	87
	88	static inline void __inetpeer_ptr_set_peer(unsigned long val, struct inet_peer peer)
	89	{
	90	/* This implicitly clears INETPEER_BASE_BIT */
	91	*val = (unsigned long) peer;
	92	}
	93
	94	static inline bool inetpeer_ptr_set_peer(unsigned long ptr, struct inet_peer peer)
	95	{
	96	unsigned long val = (unsigned long) peer;
	97	unsigned long orig = *ptr;
	98
7b34ca2a	99	if (!(orig & INETPEER_BASE_BIT) \|\|
97bab73f DM	100	cmpxchg(ptr, orig, val) != orig)
	101	return false;
	102	return true;
	103	}
	104
	105	static inline void inetpeer_init_ptr(unsigned long ptr, struct inet_peer_base base)
	106	{
	107	*ptr = (unsigned long) base \| INETPEER_BASE_BIT;
	108	}
	109
	110	static inline void inetpeer_transfer_peer(unsigned long to, unsigned long from)
	111	{
	112	unsigned long val = *from;
	113
	114	*to = val;
	115	if (inetpeer_ptr_is_peer(val)) {
	116	struct inet_peer *peer = inetpeer_ptr(val);
	117	atomic_inc(&peer->refcnt);
	118	}
	119	}
	120
1fd51155	121	void inet_peer_base_init(struct inet_peer_base *);
c3426b47	122
1fd51155	123	void inet_initpeers(void) __init;
1da177e4	124
144001bd DM	125	#define INETPEER_METRICS_NEW (~(u32) 0)
	126
	127	static inline bool inet_metrics_new(const struct inet_peer *p)
	128	{
	129	return p->metrics[RTAX_LOCK-1] == INETPEER_METRICS_NEW;
	130	}
	131
1da177e4	132	/* can be called with or without local BH being disabled */
c0efc887	133	struct inet_peer inet_getpeer(struct inet_peer_base base,
c8a627ed G	134	const struct inetpeer_addr *daddr,
c8a627ed G	135	int create);
b534ecf1	136
c0efc887	137	static inline struct inet_peer inet_getpeer_v4(struct inet_peer_base base,
54db0cc2 G	138	__be32 v4daddr,
54db0cc2 G	139	int create)
b534ecf1	140	{
8790ca17	141	struct inetpeer_addr daddr;
b534ecf1	142
7a71ed89	143	daddr.addr.a4 = v4daddr;
b534ecf1	144	daddr.family = AF_INET;
c0efc887	145	return inet_getpeer(base, &daddr, create);
b534ecf1	146	}
1da177e4	147
c0efc887	148	static inline struct inet_peer inet_getpeer_v6(struct inet_peer_base base,
54db0cc2 G	149	const struct in6_addr *v6daddr,
54db0cc2 G	150	int create)
672f007d	151	{
8790ca17	152	struct inetpeer_addr daddr;
672f007d	153
4e3fd7a0	154	(struct in6_addr )daddr.addr.a6 = *v6daddr;
672f007d	155	daddr.family = AF_INET6;
c0efc887	156	return inet_getpeer(base, &daddr, create);
672f007d DM	157	}
672f007d DM	158
1da177e4	159	/* can be called from BH context or outside */
1fd51155 JP	160	void inet_putpeer(struct inet_peer *p);
1fd51155 JP	161	bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
1da177e4	162
1fd51155	163	void inetpeer_invalidate_tree(struct inet_peer_base *);
5faa5df1	164
317fe0e6	165	/*
73f156a6	166	* temporary check to make sure we dont access rid, tcp_ts,
317fe0e6 ED	167	* tcp_ts_stamp if no refcount is taken on inet_peer
	168	*/
	169	static inline void inet_peer_refcheck(const struct inet_peer *p)
	170	{
	171	WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
	172	}
1da177e4	173	#endif /* _NET_INETPEER_H */