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9#ifndef _NET_DST_H
10#define _NET_DST_H
11
12#include <net/dst_ops.h>
13#include <linux/netdevice.h>
14#include <linux/rtnetlink.h>
15#include <linux/rcupdate.h>
16#include <linux/bug.h>
17#include <linux/jiffies.h>
18#include <linux/refcount.h>
19#include <net/neighbour.h>
20#include <asm/processor.h>
21
22struct sk_buff;
23
24struct dst_entry {
25 struct net_device *dev;
26 struct dst_ops *ops;
27 unsigned long _metrics;
28 unsigned long expires;
29#ifdef CONFIG_XFRM
30 struct xfrm_state *xfrm;
31#else
32 void *__pad1;
33#endif
34 int (*input)(struct sk_buff *);
35 int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
36
37 unsigned short flags;
38#define DST_HOST 0x0001
39#define DST_NOXFRM 0x0002
40#define DST_NOPOLICY 0x0004
41#define DST_NOCOUNT 0x0008
42#define DST_FAKE_RTABLE 0x0010
43#define DST_XFRM_TUNNEL 0x0020
44#define DST_XFRM_QUEUE 0x0040
45#define DST_METADATA 0x0080
46
47
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52
53
54
55 short obsolete;
56#define DST_OBSOLETE_NONE 0
57#define DST_OBSOLETE_DEAD 2
58#define DST_OBSOLETE_FORCE_CHK -1
59#define DST_OBSOLETE_KILL -2
60 unsigned short header_len;
61 unsigned short trailer_len;
62
63
64
65
66
67#ifdef CONFIG_64BIT
68 atomic_t __refcnt;
69#endif
70 int __use;
71 unsigned long lastuse;
72 struct lwtunnel_state *lwtstate;
73 struct rcu_head rcu_head;
74 short error;
75 short __pad;
76 __u32 tclassid;
77#ifndef CONFIG_64BIT
78 atomic_t __refcnt;
79#endif
80};
81
82struct dst_metrics {
83 u32 metrics[RTAX_MAX];
84 refcount_t refcnt;
85};
86extern const struct dst_metrics dst_default_metrics;
87
88u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
89
90#define DST_METRICS_READ_ONLY 0x1UL
91#define DST_METRICS_REFCOUNTED 0x2UL
92#define DST_METRICS_FLAGS 0x3UL
93#define __DST_METRICS_PTR(Y) \
94 ((u32 *)((Y) & ~DST_METRICS_FLAGS))
95#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
96
97static inline bool dst_metrics_read_only(const struct dst_entry *dst)
98{
99 return dst->_metrics & DST_METRICS_READ_ONLY;
100}
101
102void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
103
104static inline void dst_destroy_metrics_generic(struct dst_entry *dst)
105{
106 unsigned long val = dst->_metrics;
107 if (!(val & DST_METRICS_READ_ONLY))
108 __dst_destroy_metrics_generic(dst, val);
109}
110
111static inline u32 *dst_metrics_write_ptr(struct dst_entry *dst)
112{
113 unsigned long p = dst->_metrics;
114
115 BUG_ON(!p);
116
117 if (p & DST_METRICS_READ_ONLY)
118 return dst->ops->cow_metrics(dst, p);
119 return __DST_METRICS_PTR(p);
120}
121
122
123
124
125static inline void dst_init_metrics(struct dst_entry *dst,
126 const u32 *src_metrics,
127 bool read_only)
128{
129 dst->_metrics = ((unsigned long) src_metrics) |
130 (read_only ? DST_METRICS_READ_ONLY : 0);
131}
132
133static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
134{
135 u32 *dst_metrics = dst_metrics_write_ptr(dest);
136
137 if (dst_metrics) {
138 u32 *src_metrics = DST_METRICS_PTR(src);
139
140 memcpy(dst_metrics, src_metrics, RTAX_MAX * sizeof(u32));
141 }
142}
143
144static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
145{
146 return DST_METRICS_PTR(dst);
147}
148
149static inline u32
150dst_metric_raw(const struct dst_entry *dst, const int metric)
151{
152 u32 *p = DST_METRICS_PTR(dst);
153
154 return p[metric-1];
155}
156
157static inline u32
158dst_metric(const struct dst_entry *dst, const int metric)
159{
160 WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
161 metric == RTAX_ADVMSS ||
162 metric == RTAX_MTU);
163 return dst_metric_raw(dst, metric);
164}
165
166static inline u32
167dst_metric_advmss(const struct dst_entry *dst)
168{
169 u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);
170
171 if (!advmss)
172 advmss = dst->ops->default_advmss(dst);
173
174 return advmss;
175}
176
177static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
178{
179 u32 *p = dst_metrics_write_ptr(dst);
180
181 if (p)
182 p[metric-1] = val;
183}
184
185
186#define DST_FEATURE_ECN_CA (1 << 31)
187
188#define DST_FEATURE_MASK (DST_FEATURE_ECN_CA)
189#define DST_FEATURE_ECN_MASK (DST_FEATURE_ECN_CA | RTAX_FEATURE_ECN)
190
191static inline u32
192dst_feature(const struct dst_entry *dst, u32 feature)
193{
194 return dst_metric(dst, RTAX_FEATURES) & feature;
195}
196
197static inline u32 dst_mtu(const struct dst_entry *dst)
198{
199 return dst->ops->mtu(dst);
200}
201
202
203static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
204{
205 return msecs_to_jiffies(dst_metric(dst, metric));
206}
207
208static inline u32
209dst_allfrag(const struct dst_entry *dst)
210{
211 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
212 return ret;
213}
214
215static inline int
216dst_metric_locked(const struct dst_entry *dst, int metric)
217{
218 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
219}
220
221static inline void dst_hold(struct dst_entry *dst)
222{
223
224
225
226
227 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
228 WARN_ON(atomic_inc_not_zero(&dst->__refcnt) == 0);
229}
230
231static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
232{
233 if (unlikely(time != dst->lastuse)) {
234 dst->__use++;
235 dst->lastuse = time;
236 }
237}
238
239static inline void dst_hold_and_use(struct dst_entry *dst, unsigned long time)
240{
241 dst_hold(dst);
242 dst_use_noref(dst, time);
243}
244
245static inline struct dst_entry *dst_clone(struct dst_entry *dst)
246{
247 if (dst)
248 dst_hold(dst);
249 return dst;
250}
251
252void dst_release(struct dst_entry *dst);
253
254void dst_release_immediate(struct dst_entry *dst);
255
256static inline void refdst_drop(unsigned long refdst)
257{
258 if (!(refdst & SKB_DST_NOREF))
259 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
260}
261
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267
268static inline void skb_dst_drop(struct sk_buff *skb)
269{
270 if (skb->_skb_refdst) {
271 refdst_drop(skb->_skb_refdst);
272 skb->_skb_refdst = 0UL;
273 }
274}
275
276static inline void __skb_dst_copy(struct sk_buff *nskb, unsigned long refdst)
277{
278 nskb->_skb_refdst = refdst;
279 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
280 dst_clone(skb_dst(nskb));
281}
282
283static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
284{
285 __skb_dst_copy(nskb, oskb->_skb_refdst);
286}
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294
295static inline bool dst_hold_safe(struct dst_entry *dst)
296{
297 return atomic_inc_not_zero(&dst->__refcnt);
298}
299
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305
306static inline void skb_dst_force(struct sk_buff *skb)
307{
308 if (skb_dst_is_noref(skb)) {
309 struct dst_entry *dst = skb_dst(skb);
310
311 WARN_ON(!rcu_read_lock_held());
312 if (!dst_hold_safe(dst))
313 dst = NULL;
314
315 skb->_skb_refdst = (unsigned long)dst;
316 }
317}
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328
329static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
330 struct net *net)
331{
332 skb->dev = dev;
333
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336
337
338
339 skb_clear_hash_if_not_l4(skb);
340 skb_set_queue_mapping(skb, 0);
341 skb_scrub_packet(skb, !net_eq(net, dev_net(dev)));
342}
343
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353
354static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
355 struct net *net)
356{
357
358 dev->stats.rx_packets++;
359 dev->stats.rx_bytes += skb->len;
360 __skb_tunnel_rx(skb, dev, net);
361}
362
363static inline u32 dst_tclassid(const struct sk_buff *skb)
364{
365#ifdef CONFIG_IP_ROUTE_CLASSID
366 const struct dst_entry *dst;
367
368 dst = skb_dst(skb);
369 if (dst)
370 return dst->tclassid;
371#endif
372 return 0;
373}
374
375int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
376static inline int dst_discard(struct sk_buff *skb)
377{
378 return dst_discard_out(&init_net, skb->sk, skb);
379}
380void *dst_alloc(struct dst_ops *ops, struct net_device *dev, int initial_ref,
381 int initial_obsolete, unsigned short flags);
382void dst_init(struct dst_entry *dst, struct dst_ops *ops,
383 struct net_device *dev, int initial_ref, int initial_obsolete,
384 unsigned short flags);
385struct dst_entry *dst_destroy(struct dst_entry *dst);
386void dst_dev_put(struct dst_entry *dst);
387
388static inline void dst_confirm(struct dst_entry *dst)
389{
390}
391
392static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
393{
394 struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
395 return IS_ERR(n) ? NULL : n;
396}
397
398static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
399 struct sk_buff *skb)
400{
401 struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
402 return IS_ERR(n) ? NULL : n;
403}
404
405static inline void dst_confirm_neigh(const struct dst_entry *dst,
406 const void *daddr)
407{
408 if (dst->ops->confirm_neigh)
409 dst->ops->confirm_neigh(dst, daddr);
410}
411
412static inline void dst_link_failure(struct sk_buff *skb)
413{
414 struct dst_entry *dst = skb_dst(skb);
415 if (dst && dst->ops && dst->ops->link_failure)
416 dst->ops->link_failure(skb);
417}
418
419static inline void dst_set_expires(struct dst_entry *dst, int timeout)
420{
421 unsigned long expires = jiffies + timeout;
422
423 if (expires == 0)
424 expires = 1;
425
426 if (dst->expires == 0 || time_before(expires, dst->expires))
427 dst->expires = expires;
428}
429
430
431static inline int dst_output(struct net *net, struct sock *sk, struct sk_buff *skb)
432{
433 return skb_dst(skb)->output(net, sk, skb);
434}
435
436
437static inline int dst_input(struct sk_buff *skb)
438{
439 return skb_dst(skb)->input(skb);
440}
441
442static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
443{
444 if (dst->obsolete)
445 dst = dst->ops->check(dst, cookie);
446 return dst;
447}
448
449
450enum {
451 XFRM_LOOKUP_ICMP = 1 << 0,
452 XFRM_LOOKUP_QUEUE = 1 << 1,
453 XFRM_LOOKUP_KEEP_DST_REF = 1 << 2,
454};
455
456struct flowi;
457#ifndef CONFIG_XFRM
458static inline struct dst_entry *xfrm_lookup(struct net *net,
459 struct dst_entry *dst_orig,
460 const struct flowi *fl,
461 const struct sock *sk,
462 int flags)
463{
464 return dst_orig;
465}
466
467static inline struct dst_entry *
468xfrm_lookup_with_ifid(struct net *net, struct dst_entry *dst_orig,
469 const struct flowi *fl, const struct sock *sk,
470 int flags, u32 if_id)
471{
472 return dst_orig;
473}
474
475static inline struct dst_entry *xfrm_lookup_route(struct net *net,
476 struct dst_entry *dst_orig,
477 const struct flowi *fl,
478 const struct sock *sk,
479 int flags)
480{
481 return dst_orig;
482}
483
484static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
485{
486 return NULL;
487}
488
489#else
490struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
491 const struct flowi *fl, const struct sock *sk,
492 int flags);
493
494struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
495 struct dst_entry *dst_orig,
496 const struct flowi *fl,
497 const struct sock *sk, int flags,
498 u32 if_id);
499
500struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
501 const struct flowi *fl, const struct sock *sk,
502 int flags);
503
504
505static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
506{
507 return dst->xfrm;
508}
509#endif
510
511static inline void skb_dst_update_pmtu(struct sk_buff *skb, u32 mtu)
512{
513 struct dst_entry *dst = skb_dst(skb);
514
515 if (dst && dst->ops->update_pmtu)
516 dst->ops->update_pmtu(dst, NULL, skb, mtu);
517}
518
519static inline void skb_tunnel_check_pmtu(struct sk_buff *skb,
520 struct dst_entry *encap_dst,
521 int headroom)
522{
523 u32 encap_mtu = dst_mtu(encap_dst);
524
525 if (skb->len > encap_mtu - headroom)
526 skb_dst_update_pmtu(skb, encap_mtu - headroom);
527}
528
529#endif
530