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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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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 union {
40 unsigned long expires;
41
42 struct dst_entry *from;
43 };
44 struct dst_entry *path;
45 void *__pad0;
46#ifdef CONFIG_XFRM
47 struct xfrm_state *xfrm;
48#else
49 void *__pad1;
50#endif
51 int (*input)(struct sk_buff *);
52 int (*output)(struct sk_buff *);
53
54 unsigned short flags;
55#define DST_HOST 0x0001
56#define DST_NOXFRM 0x0002
57#define DST_NOPOLICY 0x0004
58#define DST_NOHASH 0x0008
59#define DST_NOCACHE 0x0010
60#define DST_NOCOUNT 0x0020
61#define DST_NOPEER 0x0040
62#define DST_FAKE_RTABLE 0x0080
63#define DST_XFRM_TUNNEL 0x0100
64
65 unsigned short pending_confirm;
66
67 short error;
68
69
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75
76
77 short obsolete;
78#define DST_OBSOLETE_NONE 0
79#define DST_OBSOLETE_DEAD 2
80#define DST_OBSOLETE_FORCE_CHK -1
81#define DST_OBSOLETE_KILL -2
82 unsigned short header_len;
83 unsigned short trailer_len;
84#ifdef CONFIG_IP_ROUTE_CLASSID
85 __u32 tclassid;
86#else
87 __u32 __pad2;
88#endif
89
90
91
92
93
94#ifdef CONFIG_64BIT
95 long __pad_to_align_refcnt[2];
96#endif
97
98
99
100
101 atomic_t __refcnt;
102 int __use;
103 unsigned long lastuse;
104 union {
105 struct dst_entry *next;
106 struct rtable __rcu *rt_next;
107 struct rt6_info *rt6_next;
108 struct dn_route __rcu *dn_next;
109 };
110};
111
112extern u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
113extern const u32 dst_default_metrics[];
114
115#define DST_METRICS_READ_ONLY 0x1UL
116#define __DST_METRICS_PTR(Y) \
117 ((u32 *)((Y) & ~DST_METRICS_READ_ONLY))
118#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
119
120static inline bool dst_metrics_read_only(const struct dst_entry *dst)
121{
122 return dst->_metrics & DST_METRICS_READ_ONLY;
123}
124
125extern void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
126
127static inline void dst_destroy_metrics_generic(struct dst_entry *dst)
128{
129 unsigned long val = dst->_metrics;
130 if (!(val & DST_METRICS_READ_ONLY))
131 __dst_destroy_metrics_generic(dst, val);
132}
133
134static inline u32 *dst_metrics_write_ptr(struct dst_entry *dst)
135{
136 unsigned long p = dst->_metrics;
137
138 BUG_ON(!p);
139
140 if (p & DST_METRICS_READ_ONLY)
141 return dst->ops->cow_metrics(dst, p);
142 return __DST_METRICS_PTR(p);
143}
144
145
146
147
148static inline void dst_init_metrics(struct dst_entry *dst,
149 const u32 *src_metrics,
150 bool read_only)
151{
152 dst->_metrics = ((unsigned long) src_metrics) |
153 (read_only ? DST_METRICS_READ_ONLY : 0);
154}
155
156static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
157{
158 u32 *dst_metrics = dst_metrics_write_ptr(dest);
159
160 if (dst_metrics) {
161 u32 *src_metrics = DST_METRICS_PTR(src);
162
163 memcpy(dst_metrics, src_metrics, RTAX_MAX * sizeof(u32));
164 }
165}
166
167static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
168{
169 return DST_METRICS_PTR(dst);
170}
171
172static inline u32
173dst_metric_raw(const struct dst_entry *dst, const int metric)
174{
175 u32 *p = DST_METRICS_PTR(dst);
176
177 return p[metric-1];
178}
179
180static inline u32
181dst_metric(const struct dst_entry *dst, const int metric)
182{
183 WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
184 metric == RTAX_ADVMSS ||
185 metric == RTAX_MTU);
186 return dst_metric_raw(dst, metric);
187}
188
189static inline u32
190dst_metric_advmss(const struct dst_entry *dst)
191{
192 u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);
193
194 if (!advmss)
195 advmss = dst->ops->default_advmss(dst);
196
197 return advmss;
198}
199
200static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
201{
202 u32 *p = dst_metrics_write_ptr(dst);
203
204 if (p)
205 p[metric-1] = val;
206}
207
208static inline u32
209dst_feature(const struct dst_entry *dst, u32 feature)
210{
211 return dst_metric(dst, RTAX_FEATURES) & feature;
212}
213
214static inline u32 dst_mtu(const struct dst_entry *dst)
215{
216 return dst->ops->mtu(dst);
217}
218
219
220static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
221{
222 return msecs_to_jiffies(dst_metric(dst, metric));
223}
224
225static inline u32
226dst_allfrag(const struct dst_entry *dst)
227{
228 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
229 return ret;
230}
231
232static inline int
233dst_metric_locked(const struct dst_entry *dst, int metric)
234{
235 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
236}
237
238static inline void dst_hold(struct dst_entry *dst)
239{
240
241
242
243
244 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
245 atomic_inc(&dst->__refcnt);
246}
247
248static inline void dst_use(struct dst_entry *dst, unsigned long time)
249{
250 dst_hold(dst);
251 dst->__use++;
252 dst->lastuse = time;
253}
254
255static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
256{
257 dst->__use++;
258 dst->lastuse = time;
259}
260
261static inline struct dst_entry *dst_clone(struct dst_entry *dst)
262{
263 if (dst)
264 atomic_inc(&dst->__refcnt);
265 return dst;
266}
267
268extern void dst_release(struct dst_entry *dst);
269
270static inline void refdst_drop(unsigned long refdst)
271{
272 if (!(refdst & SKB_DST_NOREF))
273 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
274}
275
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281
282static inline void skb_dst_drop(struct sk_buff *skb)
283{
284 if (skb->_skb_refdst) {
285 refdst_drop(skb->_skb_refdst);
286 skb->_skb_refdst = 0UL;
287 }
288}
289
290static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
291{
292 nskb->_skb_refdst = oskb->_skb_refdst;
293 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
294 dst_clone(skb_dst(nskb));
295}
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301
302
303static inline void skb_dst_force(struct sk_buff *skb)
304{
305 if (skb_dst_is_noref(skb)) {
306 WARN_ON(!rcu_read_lock_held());
307 skb->_skb_refdst &= ~SKB_DST_NOREF;
308 dst_clone(skb_dst(skb));
309 }
310}
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320
321static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
322{
323 skb->dev = dev;
324
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328
329
330 if (!skb->l4_rxhash)
331 skb->rxhash = 0;
332 skb_set_queue_mapping(skb, 0);
333 skb_dst_drop(skb);
334 nf_reset(skb);
335}
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345
346static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
347{
348
349 dev->stats.rx_packets++;
350 dev->stats.rx_bytes += skb->len;
351 __skb_tunnel_rx(skb, dev);
352}
353
354
355
356
357
358static inline struct dst_entry *skb_dst_pop(struct sk_buff *skb)
359{
360 struct dst_entry *child = dst_clone(skb_dst(skb)->child);
361
362 skb_dst_drop(skb);
363 return child;
364}
365
366extern int dst_discard(struct sk_buff *skb);
367extern void *dst_alloc(struct dst_ops *ops, struct net_device *dev,
368 int initial_ref, int initial_obsolete,
369 unsigned short flags);
370extern void __dst_free(struct dst_entry *dst);
371extern struct dst_entry *dst_destroy(struct dst_entry *dst);
372
373static inline void dst_free(struct dst_entry *dst)
374{
375 if (dst->obsolete > 0)
376 return;
377 if (!atomic_read(&dst->__refcnt)) {
378 dst = dst_destroy(dst);
379 if (!dst)
380 return;
381 }
382 __dst_free(dst);
383}
384
385static inline void dst_rcu_free(struct rcu_head *head)
386{
387 struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
388 dst_free(dst);
389}
390
391static inline void dst_confirm(struct dst_entry *dst)
392{
393 dst->pending_confirm = 1;
394}
395
396static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n,
397 struct sk_buff *skb)
398{
399 struct hh_cache *hh;
400
401 if (unlikely(dst->pending_confirm)) {
402 n->confirmed = jiffies;
403 dst->pending_confirm = 0;
404 }
405
406 hh = &n->hh;
407 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
408 return neigh_hh_output(hh, skb);
409 else
410 return n->output(n, skb);
411}
412
413static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
414{
415 return dst->ops->neigh_lookup(dst, NULL, daddr);
416}
417
418static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
419 struct sk_buff *skb)
420{
421 return dst->ops->neigh_lookup(dst, skb, NULL);
422}
423
424static inline void dst_link_failure(struct sk_buff *skb)
425{
426 struct dst_entry *dst = skb_dst(skb);
427 if (dst && dst->ops && dst->ops->link_failure)
428 dst->ops->link_failure(skb);
429}
430
431static inline void dst_set_expires(struct dst_entry *dst, int timeout)
432{
433 unsigned long expires = jiffies + timeout;
434
435 if (expires == 0)
436 expires = 1;
437
438 if (dst->expires == 0 || time_before(expires, dst->expires))
439 dst->expires = expires;
440}
441
442
443static inline int dst_output(struct sk_buff *skb)
444{
445 return skb_dst(skb)->output(skb);
446}
447
448
449static inline int dst_input(struct sk_buff *skb)
450{
451 return skb_dst(skb)->input(skb);
452}
453
454static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
455{
456 if (dst->obsolete)
457 dst = dst->ops->check(dst, cookie);
458 return dst;
459}
460
461extern void dst_init(void);
462
463
464enum {
465 XFRM_LOOKUP_ICMP = 1 << 0,
466};
467
468struct flowi;
469#ifndef CONFIG_XFRM
470static inline struct dst_entry *xfrm_lookup(struct net *net,
471 struct dst_entry *dst_orig,
472 const struct flowi *fl, struct sock *sk,
473 int flags)
474{
475 return dst_orig;
476}
477#else
478extern struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
479 const struct flowi *fl, struct sock *sk,
480 int flags);
481#endif
482
483#endif
484