[GitHub/mt8127/android_kernel_alcatel_ttab.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;
	u32			flush_seq;
	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);
	}
}

extern 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 */
extern void inet_putpeer(struct inet_peer *p);
extern bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);

extern void inetpeer_invalidate_tree(struct inet_peer_base *);
extern void inetpeer_invalidate_family(int family);

/*
 * 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
	1	/*
	2	* INETPEER - A storage for permanent information about peers
	3	*
	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>
	14	#include <linux/rtnetlink.h>
	15	#include <net/ipv6.h>
	16	#include <linux/atomic.h>
	17
	18	struct inetpeer_addr_base {
	19	union {
	20	__be32 a4;
	21	__be32 a6[4];
	22	};
	23	};
	24
	25	struct inetpeer_addr {
	26	struct inetpeer_addr_base addr;
	27	__u16 family;
	28	};
	29
	30	struct inet_peer {
	31	/* group together avl_left,avl_right,v4daddr to speedup lookups */
	32	struct inet_peer __rcu avl_left, avl_right;
	33	struct inetpeer_addr daddr;
	34	__u32 avl_height;
	35
	36	u32 metrics[RTAX_MAX];
	37	u32 rate_tokens; /* rate limiting for ICMP */
	38	unsigned long rate_last;
	39	union {
	40	struct list_head gc_list;
	41	struct rcu_head gc_rcu;
	42	};
	43	/*
	44	* Once inet_peer is queued for deletion (refcnt == -1), following field
	45	* is not available: rid
	46	* We can share memory with rcu_head to help keep inet_peer small.
	47	*/
	48	union {
	49	struct {
	50	atomic_t rid; /* Frag reception counter */
	51	};
	52	struct rcu_head rcu;
	53	struct inet_peer *gc_next;
	54	};
	55
	56	/* following fields might be frequently dirtied */
	57	__u32 dtime; /* the time of last use of not referenced entries */
	58	atomic_t refcnt;
	59	};
	60
	61	struct inet_peer_base {
	62	struct inet_peer __rcu *root;
	63	seqlock_t lock;
	64	u32 flush_seq;
	65	int total;
	66	};
	67
	68	#define INETPEER_BASE_BIT 0x1UL
	69
	70	static inline struct inet_peer *inetpeer_ptr(unsigned long val)
	71	{
	72	BUG_ON(val & INETPEER_BASE_BIT);
	73	return (struct inet_peer *) val;
	74	}
	75
	76	static inline struct inet_peer_base *inetpeer_base_ptr(unsigned long val)
	77	{
	78	if (!(val & INETPEER_BASE_BIT))
	79	return NULL;
	80	val &= ~INETPEER_BASE_BIT;
	81	return (struct inet_peer_base *) val;
	82	}
	83
	84	static inline bool inetpeer_ptr_is_peer(unsigned long val)
	85	{
	86	return !(val & INETPEER_BASE_BIT);
	87	}
	88
	89	static inline void __inetpeer_ptr_set_peer(unsigned long val, struct inet_peer peer)
	90	{
	91	/* This implicitly clears INETPEER_BASE_BIT */
	92	*val = (unsigned long) peer;
	93	}
	94
	95	static inline bool inetpeer_ptr_set_peer(unsigned long ptr, struct inet_peer peer)
	96	{
	97	unsigned long val = (unsigned long) peer;
	98	unsigned long orig = *ptr;
	99
	100	if (!(orig & INETPEER_BASE_BIT) \|\|
	101	cmpxchg(ptr, orig, val) != orig)
	102	return false;
	103	return true;
	104	}
	105
	106	static inline void inetpeer_init_ptr(unsigned long ptr, struct inet_peer_base base)
	107	{
	108	*ptr = (unsigned long) base \| INETPEER_BASE_BIT;
	109	}
	110
	111	static inline void inetpeer_transfer_peer(unsigned long to, unsigned long from)
	112	{
	113	unsigned long val = *from;
	114
	115	*to = val;
	116	if (inetpeer_ptr_is_peer(val)) {
	117	struct inet_peer *peer = inetpeer_ptr(val);
	118	atomic_inc(&peer->refcnt);
	119	}
	120	}
	121
	122	extern void inet_peer_base_init(struct inet_peer_base *);
	123
	124	void inet_initpeers(void) __init;
	125
	126	#define INETPEER_METRICS_NEW (~(u32) 0)
	127
	128	static inline bool inet_metrics_new(const struct inet_peer *p)
	129	{
	130	return p->metrics[RTAX_LOCK-1] == INETPEER_METRICS_NEW;
	131	}
	132
	133	/* can be called with or without local BH being disabled */
	134	struct inet_peer inet_getpeer(struct inet_peer_base base,
	135	const struct inetpeer_addr *daddr,
	136	int create);
	137
	138	static inline struct inet_peer inet_getpeer_v4(struct inet_peer_base base,
	139	__be32 v4daddr,
	140	int create)
	141	{
	142	struct inetpeer_addr daddr;
	143
	144	daddr.addr.a4 = v4daddr;
	145	daddr.family = AF_INET;
	146	return inet_getpeer(base, &daddr, create);
	147	}
	148
	149	static inline struct inet_peer inet_getpeer_v6(struct inet_peer_base base,
	150	const struct in6_addr *v6daddr,
	151	int create)
	152	{
	153	struct inetpeer_addr daddr;
	154
	155	(struct in6_addr )daddr.addr.a6 = *v6daddr;
	156	daddr.family = AF_INET6;
	157	return inet_getpeer(base, &daddr, create);
	158	}
	159
	160	/* can be called from BH context or outside */
	161	extern void inet_putpeer(struct inet_peer *p);
	162	extern bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
	163
	164	extern void inetpeer_invalidate_tree(struct inet_peer_base *);
	165	extern void inetpeer_invalidate_family(int family);
	166
	167	/*
	168	* temporary check to make sure we dont access rid, tcp_ts,
	169	* tcp_ts_stamp if no refcount is taken on inet_peer
	170	*/
	171	static inline void inet_peer_refcheck(const struct inet_peer *p)
	172	{
	173	WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
	174	}
	175
	176	#endif /* _NET_INETPEER_H */