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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/bug.h>
16#include <linux/jiffies.h>
17#include <net/neighbour.h>
18#include <asm/processor.h>
19
20#define DST_GC_MIN (HZ/10)
21#define DST_GC_INC (HZ/2)
22#define DST_GC_MAX (120*HZ)
23
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28
29
30
31struct sk_buff;
32
33struct dst_entry {
34 struct rcu_head rcu_head;
35 struct dst_entry *child;
36 struct net_device *dev;
37 struct dst_ops *ops;
38 unsigned long _metrics;
39 unsigned long expires;
40 struct dst_entry *path;
41 struct dst_entry *from;
42#ifdef CONFIG_XFRM
43 struct xfrm_state *xfrm;
44#else
45 void *__pad1;
46#endif
47 int (*input)(struct sk_buff *);
48 int (*output)(struct sock *sk, struct sk_buff *skb);
49
50 unsigned short flags;
51#define DST_HOST 0x0001
52#define DST_NOXFRM 0x0002
53#define DST_NOPOLICY 0x0004
54#define DST_NOHASH 0x0008
55#define DST_NOCACHE 0x0010
56#define DST_NOCOUNT 0x0020
57#define DST_FAKE_RTABLE 0x0040
58#define DST_XFRM_TUNNEL 0x0080
59#define DST_XFRM_QUEUE 0x0100
60
61 unsigned short pending_confirm;
62
63 short error;
64
65
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71
72
73 short obsolete;
74#define DST_OBSOLETE_NONE 0
75#define DST_OBSOLETE_DEAD 2
76#define DST_OBSOLETE_FORCE_CHK -1
77#define DST_OBSOLETE_KILL -2
78 unsigned short header_len;
79 unsigned short trailer_len;
80#ifdef CONFIG_IP_ROUTE_CLASSID
81 __u32 tclassid;
82#else
83 __u32 __pad2;
84#endif
85
86
87
88
89
90#ifdef CONFIG_64BIT
91 long __pad_to_align_refcnt[2];
92#endif
93
94
95
96
97 atomic_t __refcnt;
98 int __use;
99 unsigned long lastuse;
100 union {
101 struct dst_entry *next;
102 struct rtable __rcu *rt_next;
103 struct rt6_info *rt6_next;
104 struct dn_route __rcu *dn_next;
105 };
106};
107
108u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
109extern const u32 dst_default_metrics[];
110
111#define DST_METRICS_READ_ONLY 0x1UL
112#define DST_METRICS_FORCE_OVERWRITE 0x2UL
113#define DST_METRICS_FLAGS 0x3UL
114#define __DST_METRICS_PTR(Y) \
115 ((u32 *)((Y) & ~DST_METRICS_FLAGS))
116#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
117
118static inline bool dst_metrics_read_only(const struct dst_entry *dst)
119{
120 return dst->_metrics & DST_METRICS_READ_ONLY;
121}
122
123static inline void dst_metrics_set_force_overwrite(struct dst_entry *dst)
124{
125 dst->_metrics |= DST_METRICS_FORCE_OVERWRITE;
126}
127
128void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
129
130static inline void dst_destroy_metrics_generic(struct dst_entry *dst)
131{
132 unsigned long val = dst->_metrics;
133 if (!(val & DST_METRICS_READ_ONLY))
134 __dst_destroy_metrics_generic(dst, val);
135}
136
137static inline u32 *dst_metrics_write_ptr(struct dst_entry *dst)
138{
139 unsigned long p = dst->_metrics;
140
141 BUG_ON(!p);
142
143 if (p & DST_METRICS_READ_ONLY)
144 return dst->ops->cow_metrics(dst, p);
145 return __DST_METRICS_PTR(p);
146}
147
148
149
150
151static inline void dst_init_metrics(struct dst_entry *dst,
152 const u32 *src_metrics,
153 bool read_only)
154{
155 dst->_metrics = ((unsigned long) src_metrics) |
156 (read_only ? DST_METRICS_READ_ONLY : 0);
157}
158
159static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
160{
161 u32 *dst_metrics = dst_metrics_write_ptr(dest);
162
163 if (dst_metrics) {
164 u32 *src_metrics = DST_METRICS_PTR(src);
165
166 memcpy(dst_metrics, src_metrics, RTAX_MAX * sizeof(u32));
167 }
168}
169
170static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
171{
172 return DST_METRICS_PTR(dst);
173}
174
175static inline u32
176dst_metric_raw(const struct dst_entry *dst, const int metric)
177{
178 u32 *p = DST_METRICS_PTR(dst);
179
180 return p[metric-1];
181}
182
183static inline u32
184dst_metric(const struct dst_entry *dst, const int metric)
185{
186 WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
187 metric == RTAX_ADVMSS ||
188 metric == RTAX_MTU);
189 return dst_metric_raw(dst, metric);
190}
191
192static inline u32
193dst_metric_advmss(const struct dst_entry *dst)
194{
195 u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);
196
197 if (!advmss)
198 advmss = dst->ops->default_advmss(dst);
199
200 return advmss;
201}
202
203static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
204{
205 u32 *p = dst_metrics_write_ptr(dst);
206
207 if (p)
208 p[metric-1] = val;
209}
210
211static inline u32
212dst_feature(const struct dst_entry *dst, u32 feature)
213{
214 return dst_metric(dst, RTAX_FEATURES) & feature;
215}
216
217static inline u32 dst_mtu(const struct dst_entry *dst)
218{
219 return dst->ops->mtu(dst);
220}
221
222
223static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
224{
225 return msecs_to_jiffies(dst_metric(dst, metric));
226}
227
228static inline u32
229dst_allfrag(const struct dst_entry *dst)
230{
231 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
232 return ret;
233}
234
235static inline int
236dst_metric_locked(const struct dst_entry *dst, int metric)
237{
238 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
239}
240
241static inline void dst_hold(struct dst_entry *dst)
242{
243
244
245
246
247 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
248 atomic_inc(&dst->__refcnt);
249}
250
251static inline void dst_use(struct dst_entry *dst, unsigned long time)
252{
253 dst_hold(dst);
254 dst->__use++;
255 dst->lastuse = time;
256}
257
258static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
259{
260 dst->__use++;
261 dst->lastuse = time;
262}
263
264static inline struct dst_entry *dst_clone(struct dst_entry *dst)
265{
266 if (dst)
267 atomic_inc(&dst->__refcnt);
268 return dst;
269}
270
271void dst_release(struct dst_entry *dst);
272
273static inline void refdst_drop(unsigned long refdst)
274{
275 if (!(refdst & SKB_DST_NOREF))
276 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
277}
278
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284
285static inline void skb_dst_drop(struct sk_buff *skb)
286{
287 if (skb->_skb_refdst) {
288 refdst_drop(skb->_skb_refdst);
289 skb->_skb_refdst = 0UL;
290 }
291}
292
293static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
294{
295 nskb->_skb_refdst = oskb->_skb_refdst;
296 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
297 dst_clone(skb_dst(nskb));
298}
299
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304
305
306static inline void skb_dst_force(struct sk_buff *skb)
307{
308 if (skb_dst_is_noref(skb)) {
309 WARN_ON(!rcu_read_lock_held());
310 skb->_skb_refdst &= ~SKB_DST_NOREF;
311 dst_clone(skb_dst(skb));
312 }
313}
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324
325static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
326 struct net *net)
327{
328 skb->dev = dev;
329
330
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333
334
335 skb_clear_hash_if_not_l4(skb);
336 skb_set_queue_mapping(skb, 0);
337 skb_scrub_packet(skb, !net_eq(net, dev_net(dev)));
338}
339
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347
348
349static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
350 struct net *net)
351{
352
353 dev->stats.rx_packets++;
354 dev->stats.rx_bytes += skb->len;
355 __skb_tunnel_rx(skb, dev, net);
356}
357
358
359
360
361
362static inline struct dst_entry *skb_dst_pop(struct sk_buff *skb)
363{
364 struct dst_entry *child = dst_clone(skb_dst(skb)->child);
365
366 skb_dst_drop(skb);
367 return child;
368}
369
370int dst_discard_sk(struct sock *sk, struct sk_buff *skb);
371static inline int dst_discard(struct sk_buff *skb)
372{
373 return dst_discard_sk(skb->sk, skb);
374}
375void *dst_alloc(struct dst_ops *ops, struct net_device *dev, int initial_ref,
376 int initial_obsolete, unsigned short flags);
377void __dst_free(struct dst_entry *dst);
378struct dst_entry *dst_destroy(struct dst_entry *dst);
379
380static inline void dst_free(struct dst_entry *dst)
381{
382 if (dst->obsolete > 0)
383 return;
384 if (!atomic_read(&dst->__refcnt)) {
385 dst = dst_destroy(dst);
386 if (!dst)
387 return;
388 }
389 __dst_free(dst);
390}
391
392static inline void dst_rcu_free(struct rcu_head *head)
393{
394 struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
395 dst_free(dst);
396}
397
398static inline void dst_confirm(struct dst_entry *dst)
399{
400 dst->pending_confirm = 1;
401}
402
403static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n,
404 struct sk_buff *skb)
405{
406 const struct hh_cache *hh;
407
408 if (dst->pending_confirm) {
409 unsigned long now = jiffies;
410
411 dst->pending_confirm = 0;
412
413 if (n->confirmed != now)
414 n->confirmed = now;
415 }
416
417 hh = &n->hh;
418 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
419 return neigh_hh_output(hh, skb);
420 else
421 return n->output(n, skb);
422}
423
424static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
425{
426 struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
427 return IS_ERR(n) ? NULL : n;
428}
429
430static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
431 struct sk_buff *skb)
432{
433 struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
434 return IS_ERR(n) ? NULL : n;
435}
436
437static inline void dst_link_failure(struct sk_buff *skb)
438{
439 struct dst_entry *dst = skb_dst(skb);
440 if (dst && dst->ops && dst->ops->link_failure)
441 dst->ops->link_failure(skb);
442}
443
444static inline void dst_set_expires(struct dst_entry *dst, int timeout)
445{
446 unsigned long expires = jiffies + timeout;
447
448 if (expires == 0)
449 expires = 1;
450
451 if (dst->expires == 0 || time_before(expires, dst->expires))
452 dst->expires = expires;
453}
454
455
456static inline int dst_output_sk(struct sock *sk, struct sk_buff *skb)
457{
458 return skb_dst(skb)->output(sk, skb);
459}
460static inline int dst_output(struct sk_buff *skb)
461{
462 return dst_output_sk(skb->sk, skb);
463}
464
465
466static inline int dst_input(struct sk_buff *skb)
467{
468 return skb_dst(skb)->input(skb);
469}
470
471static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
472{
473 if (dst->obsolete)
474 dst = dst->ops->check(dst, cookie);
475 return dst;
476}
477
478void dst_init(void);
479
480
481enum {
482 XFRM_LOOKUP_ICMP = 1 << 0,
483 XFRM_LOOKUP_QUEUE = 1 << 1,
484 XFRM_LOOKUP_KEEP_DST_REF = 1 << 2,
485};
486
487struct flowi;
488#ifndef CONFIG_XFRM
489static inline struct dst_entry *xfrm_lookup(struct net *net,
490 struct dst_entry *dst_orig,
491 const struct flowi *fl, struct sock *sk,
492 int flags)
493{
494 return dst_orig;
495}
496
497static inline struct dst_entry *xfrm_lookup_route(struct net *net,
498 struct dst_entry *dst_orig,
499 const struct flowi *fl,
500 struct sock *sk,
501 int flags)
502{
503 return dst_orig;
504}
505
506static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
507{
508 return NULL;
509}
510
511#else
512struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
513 const struct flowi *fl, struct sock *sk,
514 int flags);
515
516struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
517 const struct flowi *fl, struct sock *sk,
518 int flags);
519
520
521static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
522{
523 return dst->xfrm;
524}
525#endif
526
527#endif
528