[mirror_ubuntu-bionic-kernel.git] / include / net / dst.h

/*
 * net/dst.h	Protocol independent destination cache definitions.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 */

#ifndef _NET_DST_H
#define _NET_DST_H

#include <net/dst_ops.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/rcupdate.h>
#include <linux/jiffies.h>
#include <net/neighbour.h>
#include <asm/processor.h>

/*
 * 0 - no debugging messages
 * 1 - rare events and bugs (default)
 * 2 - trace mode.
 */
#define RT_CACHE_DEBUG		0

#define DST_GC_MIN	(HZ/10)
#define DST_GC_INC	(HZ/2)
#define DST_GC_MAX	(120*HZ)

/* Each dst_entry has reference count and sits in some parent list(s).
 * When it is removed from parent list, it is "freed" (dst_free).
 * After this it enters dead state (dst->obsolete > 0) and if its refcnt
 * is zero, it can be destroyed immediately, otherwise it is added
 * to gc list and garbage collector periodically checks the refcnt.
 */

struct sk_buff;

struct dst_entry {
	struct rcu_head		rcu_head;
	struct dst_entry	*child;
	struct net_device       *dev;
	short			error;
	short			obsolete;
	int			flags;
#define DST_HOST		0x0001
#define DST_NOXFRM		0x0002
#define DST_NOPOLICY		0x0004
#define DST_NOHASH		0x0008
#define DST_NOCACHE		0x0010
	unsigned long		expires;

	unsigned short		header_len;	/* more space at head required */
	unsigned short		trailer_len;	/* space to reserve at tail */

	unsigned int		rate_tokens;
	unsigned long		rate_last;	/* rate limiting for ICMP */

	struct dst_entry	*path;

	struct neighbour	*neighbour;
	struct hh_cache		*hh;
#ifdef CONFIG_XFRM
	struct xfrm_state	*xfrm;
#else
	void			*__pad1;
#endif
	int			(*input)(struct sk_buff*);
	int			(*output)(struct sk_buff*);

	struct  dst_ops	        *ops;

	u32			_metrics[RTAX_MAX];

#ifdef CONFIG_IP_ROUTE_CLASSID
	__u32			tclassid;
#else
	__u32			__pad2;
#endif


	/*
	 * Align __refcnt to a 64 bytes alignment
	 * (L1_CACHE_SIZE would be too much)
	 */
#ifdef CONFIG_64BIT
	long			__pad_to_align_refcnt[1];
#endif
	/*
	 * __refcnt wants to be on a different cache line from
	 * input/output/ops or performance tanks badly
	 */
	atomic_t		__refcnt;	/* client references	*/
	int			__use;
	unsigned long		lastuse;
	union {
		struct dst_entry	*next;
		struct rtable __rcu	*rt_next;
		struct rt6_info		*rt6_next;
		struct dn_route __rcu	*dn_next;
	};
};

#ifdef __KERNEL__

static inline u32
dst_metric_raw(const struct dst_entry *dst, const int metric)
{
	return dst->_metrics[metric-1];
}

static inline u32
dst_metric(const struct dst_entry *dst, const int metric)
{
	WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
		     metric == RTAX_ADVMSS ||
		     metric == RTAX_MTU);
	return dst_metric_raw(dst, metric);
}

static inline u32
dst_metric_advmss(const struct dst_entry *dst)
{
	u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);

	if (!advmss)
		advmss = dst->ops->default_advmss(dst);

	return advmss;
}

static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
{
	dst->_metrics[metric-1] = val;
}

static inline void dst_import_metrics(struct dst_entry *dst, const u32 *src_metrics)
{
	memcpy(dst->_metrics, src_metrics, RTAX_MAX * sizeof(u32));
}

static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
{
	dst_import_metrics(dest, src->_metrics);
}

static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
{
	return dst->_metrics;
}

static inline u32
dst_feature(const struct dst_entry *dst, u32 feature)
{
	return dst_metric(dst, RTAX_FEATURES) & feature;
}

static inline u32 dst_mtu(const struct dst_entry *dst)
{
	u32 mtu = dst_metric_raw(dst, RTAX_MTU);

	if (!mtu)
		mtu = dst->ops->default_mtu(dst);

	return mtu;
}

/* RTT metrics are stored in milliseconds for user ABI, but used as jiffies */
static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
{
	return msecs_to_jiffies(dst_metric(dst, metric));
}

static inline void set_dst_metric_rtt(struct dst_entry *dst, int metric,
				      unsigned long rtt)
{
	dst_metric_set(dst, metric, jiffies_to_msecs(rtt));
}

static inline u32
dst_allfrag(const struct dst_entry *dst)
{
	int ret = dst_feature(dst,  RTAX_FEATURE_ALLFRAG);
	/* Yes, _exactly_. This is paranoia. */
	barrier();
	return ret;
}

static inline int
dst_metric_locked(const struct dst_entry *dst, int metric)
{
	return dst_metric(dst, RTAX_LOCK) & (1<<metric);
}

static inline void dst_hold(struct dst_entry * dst)
{
	/*
	 * If your kernel compilation stops here, please check
	 * __pad_to_align_refcnt declaration in struct dst_entry
	 */
	BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
	atomic_inc(&dst->__refcnt);
}

static inline void dst_use(struct dst_entry *dst, unsigned long time)
{
	dst_hold(dst);
	dst->__use++;
	dst->lastuse = time;
}

static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
{
	dst->__use++;
	dst->lastuse = time;
}

static inline
struct dst_entry * dst_clone(struct dst_entry * dst)
{
	if (dst)
		atomic_inc(&dst->__refcnt);
	return dst;
}

extern void dst_release(struct dst_entry *dst);

static inline void refdst_drop(unsigned long refdst)
{
	if (!(refdst & SKB_DST_NOREF))
		dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
}

/**
 * skb_dst_drop - drops skb dst
 * @skb: buffer
 *
 * Drops dst reference count if a reference was taken.
 */
static inline void skb_dst_drop(struct sk_buff *skb)
{
	if (skb->_skb_refdst) {
		refdst_drop(skb->_skb_refdst);
		skb->_skb_refdst = 0UL;
	}
}

static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
{
	nskb->_skb_refdst = oskb->_skb_refdst;
	if (!(nskb->_skb_refdst & SKB_DST_NOREF))
		dst_clone(skb_dst(nskb));
}

/**
 * skb_dst_force - makes sure skb dst is refcounted
 * @skb: buffer
 *
 * If dst is not yet refcounted, let's do it
 */
static inline void skb_dst_force(struct sk_buff *skb)
{
	if (skb_dst_is_noref(skb)) {
		WARN_ON(!rcu_read_lock_held());
		skb->_skb_refdst &= ~SKB_DST_NOREF;
		dst_clone(skb_dst(skb));
	}
}


/**
 *	__skb_tunnel_rx - prepare skb for rx reinsert
 *	@skb: buffer
 *	@dev: tunnel device
 *
 *	After decapsulation, packet is going to re-enter (netif_rx()) our stack,
 *	so make some cleanups. (no accounting done)
 */
static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
{
	skb->dev = dev;
	skb->rxhash = 0;
	skb_set_queue_mapping(skb, 0);
	skb_dst_drop(skb);
	nf_reset(skb);
}

/**
 *	skb_tunnel_rx - prepare skb for rx reinsert
 *	@skb: buffer
 *	@dev: tunnel device
 *
 *	After decapsulation, packet is going to re-enter (netif_rx()) our stack,
 *	so make some cleanups, and perform accounting.
 *	Note: this accounting is not SMP safe.
 */
static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
{
	/* TODO : stats should be SMP safe */
	dev->stats.rx_packets++;
	dev->stats.rx_bytes += skb->len;
	__skb_tunnel_rx(skb, dev);
}

/* Children define the path of the packet through the
 * Linux networking.  Thus, destinations are stackable.
 */

static inline struct dst_entry *skb_dst_pop(struct sk_buff *skb)
{
	struct dst_entry *child = skb_dst(skb)->child;

	skb_dst_drop(skb);
	return child;
}

extern int dst_discard(struct sk_buff *skb);
extern void * dst_alloc(struct dst_ops * ops);
extern void __dst_free(struct dst_entry * dst);
extern struct dst_entry *dst_destroy(struct dst_entry * dst);

static inline void dst_free(struct dst_entry * dst)
{
	if (dst->obsolete > 1)
		return;
	if (!atomic_read(&dst->__refcnt)) {
		dst = dst_destroy(dst);
		if (!dst)
			return;
	}
	__dst_free(dst);
}

static inline void dst_rcu_free(struct rcu_head *head)
{
	struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
	dst_free(dst);
}

static inline void dst_confirm(struct dst_entry *dst)
{
	if (dst)
		neigh_confirm(dst->neighbour);
}

static inline void dst_link_failure(struct sk_buff *skb)
{
	struct dst_entry *dst = skb_dst(skb);
	if (dst && dst->ops && dst->ops->link_failure)
		dst->ops->link_failure(skb);
}

static inline void dst_set_expires(struct dst_entry *dst, int timeout)
{
	unsigned long expires = jiffies + timeout;

	if (expires == 0)
		expires = 1;

	if (dst->expires == 0 || time_before(expires, dst->expires))
		dst->expires = expires;
}

/* Output packet to network from transport.  */
static inline int dst_output(struct sk_buff *skb)
{
	return skb_dst(skb)->output(skb);
}

/* Input packet from network to transport.  */
static inline int dst_input(struct sk_buff *skb)
{
	return skb_dst(skb)->input(skb);
}

static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
{
	if (dst->obsolete)
		dst = dst->ops->check(dst, cookie);
	return dst;
}

extern void		dst_init(void);

/* Flags for xfrm_lookup flags argument. */
enum {
	XFRM_LOOKUP_WAIT = 1 << 0,
	XFRM_LOOKUP_ICMP = 1 << 1,
};

struct flowi;
#ifndef CONFIG_XFRM
static inline int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
			      struct flowi *fl, struct sock *sk, int flags)
{
	return 0;
} 
static inline int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
				struct flowi *fl, struct sock *sk, int flags)
{
	return 0;
}
#else
extern int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
		       struct flowi *fl, struct sock *sk, int flags);
extern int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
			 struct flowi *fl, struct sock *sk, int flags);
#endif
#endif

#endif /* _NET_DST_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/dst.h Protocol independent destination cache definitions.
	3	*
	4	* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
	5	*
	6	*/
	7
	8	#ifndef _NET_DST_H
	9	#define _NET_DST_H
	10
86393e52	11	#include <net/dst_ops.h>
14c85021	12	#include <linux/netdevice.h>
1da177e4 LT	13	#include <linux/rtnetlink.h>
	14	#include <linux/rcupdate.h>
	15	#include <linux/jiffies.h>
	16	#include <net/neighbour.h>
	17	#include <asm/processor.h>
	18
	19	/*
	20	* 0 - no debugging messages
	21	* 1 - rare events and bugs (default)
	22	* 2 - trace mode.
	23	*/
	24	#define RT_CACHE_DEBUG 0
	25
	26	#define DST_GC_MIN (HZ/10)
	27	#define DST_GC_INC (HZ/2)
	28	#define DST_GC_MAX (120*HZ)
	29
	30	/* Each dst_entry has reference count and sits in some parent list(s).
	31	* When it is removed from parent list, it is "freed" (dst_free).
	32	* After this it enters dead state (dst->obsolete > 0) and if its refcnt
	33	* is zero, it can be destroyed immediately, otherwise it is added
	34	* to gc list and garbage collector periodically checks the refcnt.
	35	*/
	36
	37	struct sk_buff;
	38
fd2c3ef7	39	struct dst_entry {
1e19e02c	40	struct rcu_head rcu_head;
1da177e4 LT	41	struct dst_entry *child;
1da177e4 LT	42	struct net_device *dev;
c4d54110 HX	43	short error;
c4d54110 HX	44	short obsolete;
1da177e4	45	int flags;
c7d4426a ED	46	#define DST_HOST 0x0001
	47	#define DST_NOXFRM 0x0002
	48	#define DST_NOPOLICY 0x0004
	49	#define DST_NOHASH 0x0008
	50	#define DST_NOCACHE 0x0010
1da177e4 LT	51	unsigned long expires;
	52
	53	unsigned short header_len; /* more space at head required */
	54	unsigned short trailer_len; /* space to reserve at tail */
	55
69a73829	56	unsigned int rate_tokens;
f1dd9c37	57	unsigned long rate_last; /* rate limiting for ICMP */
69a73829	58
f1dd9c37	59	struct dst_entry *path;
1da177e4	60
1da177e4 LT	61	struct neighbour *neighbour;
1da177e4 LT	62	struct hh_cache *hh;
def8b4fa	63	#ifdef CONFIG_XFRM
1da177e4	64	struct xfrm_state *xfrm;
5635c10d ED	65	#else
5635c10d ED	66	void *__pad1;
def8b4fa	67	#endif
1da177e4 LT	68	int (input)(struct sk_buff);
	69	int (output)(struct sk_buff);
	70
1da177e4	71	struct dst_ops *ops;
f1dd9c37	72
defb3519	73	u32 _metrics[RTAX_MAX];
f1dd9c37	74
c7066f70	75	#ifdef CONFIG_IP_ROUTE_CLASSID
f1dd9c37	76	__u32 tclassid;
5635c10d ED	77	#else
5635c10d ED	78	__u32 __pad2;
f1dd9c37 ZY	79	#endif
f1dd9c37 ZY	80
5635c10d ED	81
	82	/*
	83	* Align __refcnt to a 64 bytes alignment
	84	* (L1_CACHE_SIZE would be too much)
	85	*/
	86	#ifdef CONFIG_64BIT
5635c10d ED	87	long __pad_to_align_refcnt[1];
5635c10d ED	88	#endif
f1dd9c37 ZY	89	/*
	90	* __refcnt wants to be on a different cache line from
	91	* input/output/ops or performance tanks badly
	92	*/
1e19e02c ED	93	atomic_t __refcnt; /* client references */
1e19e02c ED	94	int __use;
f1dd9c37	95	unsigned long lastuse;
1e19e02c	96	union {
fc766e4c ED	97	struct dst_entry *next;
	98	struct rtable __rcu *rt_next;
	99	struct rt6_info *rt6_next;
	100	struct dn_route __rcu *dn_next;
1e19e02c	101	};
1da177e4 LT	102	};
1da177e4 LT	103
1da177e4 LT	104	#ifdef __KERNEL__
	105
	106	static inline u32
5170ae82	107	dst_metric_raw(const struct dst_entry *dst, const int metric)
1da177e4	108	{
defb3519 DM	109	return dst->_metrics[metric-1];
	110	}
	111
5170ae82 DM	112	static inline u32
	113	dst_metric(const struct dst_entry *dst, const int metric)
	114	{
0dbaee3b	115	WARN_ON_ONCE(metric == RTAX_HOPLIMIT \|\|
d33e4553 DM	116	metric == RTAX_ADVMSS \|\|
d33e4553 DM	117	metric == RTAX_MTU);
5170ae82 DM	118	return dst_metric_raw(dst, metric);
	119	}
	120
0dbaee3b DM	121	static inline u32
	122	dst_metric_advmss(const struct dst_entry *dst)
	123	{
	124	u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);
	125
	126	if (!advmss)
	127	advmss = dst->ops->default_advmss(dst);
	128
	129	return advmss;
	130	}
	131
defb3519 DM	132	static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
	133	{
	134	dst->_metrics[metric-1] = val;
	135	}
	136
	137	static inline void dst_import_metrics(struct dst_entry dst, const u32 src_metrics)
	138	{
	139	memcpy(dst->_metrics, src_metrics, RTAX_MAX * sizeof(u32));
	140	}
	141
	142	static inline void dst_copy_metrics(struct dst_entry dest, const struct dst_entry src)
	143	{
	144	dst_import_metrics(dest, src->_metrics);
	145	}
	146
	147	static inline u32 dst_metrics_ptr(struct dst_entry dst)
	148	{
	149	return dst->_metrics;
1da177e4 LT	150	}
1da177e4 LT	151
0c3adfb8 GBY	152	static inline u32
	153	dst_feature(const struct dst_entry *dst, u32 feature)
	154	{
bb5b7c11	155	return dst_metric(dst, RTAX_FEATURES) & feature;
0c3adfb8 GBY	156	}
0c3adfb8 GBY	157
1da177e4 LT	158	static inline u32 dst_mtu(const struct dst_entry *dst)
1da177e4 LT	159	{
d33e4553 DM	160	u32 mtu = dst_metric_raw(dst, RTAX_MTU);
	161
	162	if (!mtu)
	163	mtu = dst->ops->default_mtu(dst);
	164
1da177e4 LT	165	return mtu;
	166	}
	167
c1e20f7c SH	168	/* RTT metrics are stored in milliseconds for user ABI, but used as jiffies */
	169	static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
	170	{
	171	return msecs_to_jiffies(dst_metric(dst, metric));
	172	}
	173
	174	static inline void set_dst_metric_rtt(struct dst_entry *dst, int metric,
	175	unsigned long rtt)
	176	{
defb3519	177	dst_metric_set(dst, metric, jiffies_to_msecs(rtt));
c1e20f7c SH	178	}
c1e20f7c SH	179
1da177e4 LT	180	static inline u32
	181	dst_allfrag(const struct dst_entry *dst)
	182	{
0c3adfb8	183	int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
1da177e4 LT	184	/* Yes, _exactly_. This is paranoia. */
	185	barrier();
	186	return ret;
	187	}
	188
	189	static inline int
d33e4553	190	dst_metric_locked(const struct dst_entry *dst, int metric)
1da177e4 LT	191	{
	192	return dst_metric(dst, RTAX_LOCK) & (1<<metric);
	193	}
	194
	195	static inline void dst_hold(struct dst_entry * dst)
	196	{
5635c10d ED	197	/*
	198	* If your kernel compilation stops here, please check
	199	* __pad_to_align_refcnt declaration in struct dst_entry
	200	*/
	201	BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
1da177e4 LT	202	atomic_inc(&dst->__refcnt);
	203	}
	204
03f49f34 PE	205	static inline void dst_use(struct dst_entry *dst, unsigned long time)
	206	{
	207	dst_hold(dst);
	208	dst->__use++;
	209	dst->lastuse = time;
	210	}
	211
7fee226a ED	212	static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
	213	{
	214	dst->__use++;
	215	dst->lastuse = time;
	216	}
	217
1da177e4 LT	218	static inline
	219	struct dst_entry * dst_clone(struct dst_entry * dst)
	220	{
	221	if (dst)
	222	atomic_inc(&dst->__refcnt);
	223	return dst;
	224	}
	225
8d330868	226	extern void dst_release(struct dst_entry *dst);
7fee226a ED	227
	228	static inline void refdst_drop(unsigned long refdst)
	229	{
	230	if (!(refdst & SKB_DST_NOREF))
	231	dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
	232	}
	233
	234	/**
	235	* skb_dst_drop - drops skb dst
	236	* @skb: buffer
	237	*
	238	* Drops dst reference count if a reference was taken.
	239	*/
adf30907 ED	240	static inline void skb_dst_drop(struct sk_buff *skb)
adf30907 ED	241	{
7fee226a ED	242	if (skb->_skb_refdst) {
	243	refdst_drop(skb->_skb_refdst);
	244	skb->_skb_refdst = 0UL;
	245	}
	246	}
	247
	248	static inline void skb_dst_copy(struct sk_buff nskb, const struct sk_buff oskb)
	249	{
	250	nskb->_skb_refdst = oskb->_skb_refdst;
	251	if (!(nskb->_skb_refdst & SKB_DST_NOREF))
	252	dst_clone(skb_dst(nskb));
	253	}
	254
	255	/**
	256	* skb_dst_force - makes sure skb dst is refcounted
	257	* @skb: buffer
	258	*
	259	* If dst is not yet refcounted, let's do it
	260	*/
	261	static inline void skb_dst_force(struct sk_buff *skb)
	262	{
	263	if (skb_dst_is_noref(skb)) {
	264	WARN_ON(!rcu_read_lock_held());
	265	skb->_skb_refdst &= ~SKB_DST_NOREF;
	266	dst_clone(skb_dst(skb));
	267	}
adf30907	268	}
1da177e4	269
d19d56dd	270
290b895e ED	271	/**
	272	* __skb_tunnel_rx - prepare skb for rx reinsert
	273	* @skb: buffer
	274	* @dev: tunnel device
	275	*
	276	* After decapsulation, packet is going to re-enter (netif_rx()) our stack,
	277	* so make some cleanups. (no accounting done)
	278	*/
	279	static inline void __skb_tunnel_rx(struct sk_buff skb, struct net_device dev)
	280	{
	281	skb->dev = dev;
	282	skb->rxhash = 0;
	283	skb_set_queue_mapping(skb, 0);
	284	skb_dst_drop(skb);
	285	nf_reset(skb);
	286	}
	287
d19d56dd ED	288	/**
	289	* skb_tunnel_rx - prepare skb for rx reinsert
	290	* @skb: buffer
	291	* @dev: tunnel device
	292	*
	293	* After decapsulation, packet is going to re-enter (netif_rx()) our stack,
	294	* so make some cleanups, and perform accounting.
290b895e	295	* Note: this accounting is not SMP safe.
d19d56dd ED	296	*/
	297	static inline void skb_tunnel_rx(struct sk_buff skb, struct net_device dev)
	298	{
d19d56dd ED	299	/* TODO : stats should be SMP safe */
	300	dev->stats.rx_packets++;
	301	dev->stats.rx_bytes += skb->len;
290b895e	302	__skb_tunnel_rx(skb, dev);
d19d56dd ED	303	}
d19d56dd ED	304
1da177e4 LT	305	/* Children define the path of the packet through the
	306	* Linux networking. Thus, destinations are stackable.
	307	*/
	308
8764ab2c	309	static inline struct dst_entry skb_dst_pop(struct sk_buff skb)
1da177e4	310	{
8764ab2c	311	struct dst_entry *child = skb_dst(skb)->child;
1da177e4	312
8764ab2c	313	skb_dst_drop(skb);
1da177e4 LT	314	return child;
	315	}
	316
352e512c	317	extern int dst_discard(struct sk_buff *skb);
1da177e4 LT	318	extern void * dst_alloc(struct dst_ops * ops);
	319	extern void __dst_free(struct dst_entry * dst);
	320	extern struct dst_entry dst_destroy(struct dst_entry dst);
	321
	322	static inline void dst_free(struct dst_entry * dst)
	323	{
	324	if (dst->obsolete > 1)
	325	return;
	326	if (!atomic_read(&dst->__refcnt)) {
	327	dst = dst_destroy(dst);
	328	if (!dst)
	329	return;
	330	}
	331	__dst_free(dst);
	332	}
	333
	334	static inline void dst_rcu_free(struct rcu_head *head)
	335	{
	336	struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
	337	dst_free(dst);
	338	}
	339
	340	static inline void dst_confirm(struct dst_entry *dst)
	341	{
	342	if (dst)
	343	neigh_confirm(dst->neighbour);
	344	}
	345
1da177e4 LT	346	static inline void dst_link_failure(struct sk_buff *skb)
1da177e4 LT	347	{
adf30907	348	struct dst_entry *dst = skb_dst(skb);
1da177e4 LT	349	if (dst && dst->ops && dst->ops->link_failure)
	350	dst->ops->link_failure(skb);
	351	}
	352
	353	static inline void dst_set_expires(struct dst_entry *dst, int timeout)
	354	{
	355	unsigned long expires = jiffies + timeout;
	356
	357	if (expires == 0)
	358	expires = 1;
	359
	360	if (dst->expires == 0 \|\| time_before(expires, dst->expires))
	361	dst->expires = expires;
	362	}
	363
	364	/* Output packet to network from transport. */
	365	static inline int dst_output(struct sk_buff *skb)
	366	{
adf30907	367	return skb_dst(skb)->output(skb);
1da177e4 LT	368	}
	369
	370	/* Input packet from network to transport. */
	371	static inline int dst_input(struct sk_buff *skb)
	372	{
adf30907	373	return skb_dst(skb)->input(skb);
1da177e4 LT	374	}
	375
	376	static inline struct dst_entry dst_check(struct dst_entry dst, u32 cookie)
	377	{
	378	if (dst->obsolete)
	379	dst = dst->ops->check(dst, cookie);
	380	return dst;
	381	}
	382
	383	extern void dst_init(void);
	384
815f4e57 HX	385	/* Flags for xfrm_lookup flags argument. */
	386	enum {
	387	XFRM_LOOKUP_WAIT = 1 << 0,
8b7817f3	388	XFRM_LOOKUP_ICMP = 1 << 1,
815f4e57 HX	389	};
815f4e57 HX	390
1da177e4 LT	391	struct flowi;
1da177e4 LT	392	#ifndef CONFIG_XFRM
52479b62 AD	393	static inline int xfrm_lookup(struct net net, struct dst_entry *dst_p,
52479b62 AD	394	struct flowi fl, struct sock sk, int flags)
1da177e4 LT	395	{
	396	return 0;
	397	}
52479b62 AD	398	static inline int __xfrm_lookup(struct net net, struct dst_entry *dst_p,
52479b62 AD	399	struct flowi fl, struct sock sk, int flags)
14e50e57 DM	400	{
	401	return 0;
	402	}
1da177e4	403	#else
52479b62 AD	404	extern int xfrm_lookup(struct net net, struct dst_entry *dst_p,
	405	struct flowi fl, struct sock sk, int flags);
	406	extern int __xfrm_lookup(struct net net, struct dst_entry *dst_p,
	407	struct flowi fl, struct sock sk, int flags);
1da177e4 LT	408	#endif
	409	#endif
	410
	411	#endif /* _NET_DST_H */