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8#ifndef _NET_DST_H
9#define _NET_DST_H
10
11#include <net/dst_ops.h>
12#include <linux/netdevice.h>
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
21
22
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
31
32
33
34
35
36
37struct sk_buff;
38
39struct dst_entry
40{
41 struct rcu_head rcu_head;
42 struct dst_entry *child;
43 struct net_device *dev;
44 short error;
45 short obsolete;
46 int flags;
47#define DST_HOST 1
48#define DST_NOXFRM 2
49#define DST_NOPOLICY 4
50#define DST_NOHASH 8
51 unsigned long expires;
52
53 unsigned short header_len;
54 unsigned short trailer_len;
55
56 unsigned int rate_tokens;
57 unsigned long rate_last;
58
59 struct dst_entry *path;
60
61 struct neighbour *neighbour;
62 struct hh_cache *hh;
63#ifdef CONFIG_XFRM
64 struct xfrm_state *xfrm;
65#else
66 void *__pad1;
67#endif
68 int (*input)(struct sk_buff*);
69 int (*output)(struct sk_buff*);
70
71 struct dst_ops *ops;
72
73 u32 metrics[RTAX_MAX];
74
75#ifdef CONFIG_NET_CLS_ROUTE
76 __u32 tclassid;
77#else
78 __u32 __pad2;
79#endif
80
81
82
83
84
85
86#ifdef CONFIG_64BIT
87 long __pad_to_align_refcnt[2];
88#else
89 long __pad_to_align_refcnt[1];
90#endif
91
92
93
94
95 atomic_t __refcnt;
96 int __use;
97 unsigned long lastuse;
98 union {
99 struct dst_entry *next;
100 struct rtable *rt_next;
101 struct rt6_info *rt6_next;
102 struct dn_route *dn_next;
103 };
104};
105
106#ifdef __KERNEL__
107
108static inline u32
109dst_metric(const struct dst_entry *dst, int metric)
110{
111 return dst->metrics[metric-1];
112}
113
114static inline u32 dst_mtu(const struct dst_entry *dst)
115{
116 u32 mtu = dst_metric(dst, RTAX_MTU);
117
118
119
120 barrier();
121 return mtu;
122}
123
124
125static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
126{
127 return msecs_to_jiffies(dst_metric(dst, metric));
128}
129
130static inline void set_dst_metric_rtt(struct dst_entry *dst, int metric,
131 unsigned long rtt)
132{
133 dst->metrics[metric-1] = jiffies_to_msecs(rtt);
134}
135
136static inline u32
137dst_allfrag(const struct dst_entry *dst)
138{
139 int ret = dst_metric(dst, RTAX_FEATURES) & RTAX_FEATURE_ALLFRAG;
140
141 barrier();
142 return ret;
143}
144
145static inline int
146dst_metric_locked(struct dst_entry *dst, int metric)
147{
148 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
149}
150
151static inline void dst_hold(struct dst_entry * dst)
152{
153
154
155
156
157 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
158 atomic_inc(&dst->__refcnt);
159}
160
161static inline void dst_use(struct dst_entry *dst, unsigned long time)
162{
163 dst_hold(dst);
164 dst->__use++;
165 dst->lastuse = time;
166}
167
168static inline
169struct dst_entry * dst_clone(struct dst_entry * dst)
170{
171 if (dst)
172 atomic_inc(&dst->__refcnt);
173 return dst;
174}
175
176extern void dst_release(struct dst_entry *dst);
177static inline void skb_dst_drop(struct sk_buff *skb)
178{
179 if (skb->_skb_dst)
180 dst_release(skb_dst(skb));
181 skb->_skb_dst = 0UL;
182}
183
184
185
186
187
188static inline struct dst_entry *dst_pop(struct dst_entry *dst)
189{
190 struct dst_entry *child = dst_clone(dst->child);
191
192 dst_release(dst);
193 return child;
194}
195
196extern int dst_discard(struct sk_buff *skb);
197extern void * dst_alloc(struct dst_ops * ops);
198extern void __dst_free(struct dst_entry * dst);
199extern struct dst_entry *dst_destroy(struct dst_entry * dst);
200
201static inline void dst_free(struct dst_entry * dst)
202{
203 if (dst->obsolete > 1)
204 return;
205 if (!atomic_read(&dst->__refcnt)) {
206 dst = dst_destroy(dst);
207 if (!dst)
208 return;
209 }
210 __dst_free(dst);
211}
212
213static inline void dst_rcu_free(struct rcu_head *head)
214{
215 struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
216 dst_free(dst);
217}
218
219static inline void dst_confirm(struct dst_entry *dst)
220{
221 if (dst)
222 neigh_confirm(dst->neighbour);
223}
224
225static inline void dst_negative_advice(struct dst_entry **dst_p)
226{
227 struct dst_entry * dst = *dst_p;
228 if (dst && dst->ops->negative_advice)
229 *dst_p = dst->ops->negative_advice(dst);
230}
231
232static inline void dst_link_failure(struct sk_buff *skb)
233{
234 struct dst_entry *dst = skb_dst(skb);
235 if (dst && dst->ops && dst->ops->link_failure)
236 dst->ops->link_failure(skb);
237}
238
239static inline void dst_set_expires(struct dst_entry *dst, int timeout)
240{
241 unsigned long expires = jiffies + timeout;
242
243 if (expires == 0)
244 expires = 1;
245
246 if (dst->expires == 0 || time_before(expires, dst->expires))
247 dst->expires = expires;
248}
249
250
251static inline int dst_output(struct sk_buff *skb)
252{
253 return skb_dst(skb)->output(skb);
254}
255
256
257static inline int dst_input(struct sk_buff *skb)
258{
259 return skb_dst(skb)->input(skb);
260}
261
262static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
263{
264 if (dst->obsolete)
265 dst = dst->ops->check(dst, cookie);
266 return dst;
267}
268
269extern void dst_init(void);
270
271
272enum {
273 XFRM_LOOKUP_WAIT = 1 << 0,
274 XFRM_LOOKUP_ICMP = 1 << 1,
275};
276
277struct flowi;
278#ifndef CONFIG_XFRM
279static inline int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
280 struct flowi *fl, struct sock *sk, int flags)
281{
282 return 0;
283}
284static inline int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
285 struct flowi *fl, struct sock *sk, int flags)
286{
287 return 0;
288}
289#else
290extern int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
291 struct flowi *fl, struct sock *sk, int flags);
292extern int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
293 struct flowi *fl, struct sock *sk, int flags);
294#endif
295#endif
296
297#endif
298