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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
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35
36
37struct sk_buff;
38
39struct dst_entry {
40 struct rcu_head rcu_head;
41 struct dst_entry *child;
42 struct net_device *dev;
43 short error;
44 short obsolete;
45 int flags;
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
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
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84
85
86#ifdef CONFIG_64BIT
87 long __pad_to_align_refcnt[1];
88#endif
89
90
91
92
93 atomic_t __refcnt;
94 int __use;
95 unsigned long lastuse;
96 union {
97 struct dst_entry *next;
98 struct rtable __rcu *rt_next;
99 struct rt6_info *rt6_next;
100 struct dn_route __rcu *dn_next;
101 };
102};
103
104#ifdef __KERNEL__
105
106static inline u32
107dst_metric_raw(const struct dst_entry *dst, const int metric)
108{
109 return dst->_metrics[metric-1];
110}
111
112static inline u32
113dst_metric(const struct dst_entry *dst, const int metric)
114{
115 WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
116 metric == RTAX_ADVMSS ||
117 metric == RTAX_MTU);
118 return dst_metric_raw(dst, metric);
119}
120
121static inline u32
122dst_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
132static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
133{
134 dst->_metrics[metric-1] = val;
135}
136
137static 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
142static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
143{
144 dst_import_metrics(dest, src->_metrics);
145}
146
147static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
148{
149 return dst->_metrics;
150}
151
152static inline u32
153dst_feature(const struct dst_entry *dst, u32 feature)
154{
155 return dst_metric(dst, RTAX_FEATURES) & feature;
156}
157
158static inline u32 dst_mtu(const struct dst_entry *dst)
159{
160 u32 mtu = dst_metric_raw(dst, RTAX_MTU);
161
162 if (!mtu)
163 mtu = dst->ops->default_mtu(dst);
164
165 return mtu;
166}
167
168
169static 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
174static inline void set_dst_metric_rtt(struct dst_entry *dst, int metric,
175 unsigned long rtt)
176{
177 dst_metric_set(dst, metric, jiffies_to_msecs(rtt));
178}
179
180static inline u32
181dst_allfrag(const struct dst_entry *dst)
182{
183 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
184
185 barrier();
186 return ret;
187}
188
189static inline int
190dst_metric_locked(const struct dst_entry *dst, int metric)
191{
192 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
193}
194
195static inline void dst_hold(struct dst_entry * dst)
196{
197
198
199
200
201 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
202 atomic_inc(&dst->__refcnt);
203}
204
205static 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
212static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
213{
214 dst->__use++;
215 dst->lastuse = time;
216}
217
218static inline
219struct dst_entry * dst_clone(struct dst_entry * dst)
220{
221 if (dst)
222 atomic_inc(&dst->__refcnt);
223 return dst;
224}
225
226extern void dst_release(struct dst_entry *dst);
227
228static 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
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239
240static inline void skb_dst_drop(struct sk_buff *skb)
241{
242 if (skb->_skb_refdst) {
243 refdst_drop(skb->_skb_refdst);
244 skb->_skb_refdst = 0UL;
245 }
246}
247
248static 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
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259
260
261static 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 }
268}
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278
279static 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
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296
297static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
298{
299
300 dev->stats.rx_packets++;
301 dev->stats.rx_bytes += skb->len;
302 __skb_tunnel_rx(skb, dev);
303}
304
305
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307
308
309static inline struct dst_entry *skb_dst_pop(struct sk_buff *skb)
310{
311 struct dst_entry *child = skb_dst(skb)->child;
312
313 skb_dst_drop(skb);
314 return child;
315}
316
317extern int dst_discard(struct sk_buff *skb);
318extern void * dst_alloc(struct dst_ops * ops);
319extern void __dst_free(struct dst_entry * dst);
320extern struct dst_entry *dst_destroy(struct dst_entry * dst);
321
322static 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
334static 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
340static inline void dst_confirm(struct dst_entry *dst)
341{
342 if (dst)
343 neigh_confirm(dst->neighbour);
344}
345
346static inline void dst_link_failure(struct sk_buff *skb)
347{
348 struct dst_entry *dst = skb_dst(skb);
349 if (dst && dst->ops && dst->ops->link_failure)
350 dst->ops->link_failure(skb);
351}
352
353static 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
365static inline int dst_output(struct sk_buff *skb)
366{
367 return skb_dst(skb)->output(skb);
368}
369
370
371static inline int dst_input(struct sk_buff *skb)
372{
373 return skb_dst(skb)->input(skb);
374}
375
376static 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
383extern void dst_init(void);
384
385
386enum {
387 XFRM_LOOKUP_WAIT = 1 << 0,
388 XFRM_LOOKUP_ICMP = 1 << 1,
389};
390
391struct flowi;
392#ifndef CONFIG_XFRM
393static inline int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
394 struct flowi *fl, struct sock *sk, int flags)
395{
396 return 0;
397}
398static inline int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
399 struct flowi *fl, struct sock *sk, int flags)
400{
401 return 0;
402}
403#else
404extern int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
405 struct flowi *fl, struct sock *sk, int flags);
406extern int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
407 struct flowi *fl, struct sock *sk, int flags);
408#endif
409#endif
410
411#endif
412