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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
24
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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 net *net, 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#define DST_METADATA 0x0200
61
62 unsigned short pending_confirm;
63
64 short error;
65
66
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71
72
73
74 short obsolete;
75#define DST_OBSOLETE_NONE 0
76#define DST_OBSOLETE_DEAD 2
77#define DST_OBSOLETE_FORCE_CHK -1
78#define DST_OBSOLETE_KILL -2
79 unsigned short header_len;
80 unsigned short trailer_len;
81#ifdef CONFIG_IP_ROUTE_CLASSID
82 __u32 tclassid;
83#else
84 __u32 __pad2;
85#endif
86
87#ifdef CONFIG_64BIT
88 struct lwtunnel_state *lwtstate;
89
90
91
92
93 long __pad_to_align_refcnt[1];
94#endif
95
96
97
98
99 atomic_t __refcnt;
100 int __use;
101 unsigned long lastuse;
102#ifndef CONFIG_64BIT
103 struct lwtunnel_state *lwtstate;
104#endif
105 union {
106 struct dst_entry *next;
107 struct rtable __rcu *rt_next;
108 struct rt6_info *rt6_next;
109 struct dn_route __rcu *dn_next;
110 };
111};
112
113u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
114extern const u32 dst_default_metrics[];
115
116#define DST_METRICS_READ_ONLY 0x1UL
117#define DST_METRICS_FLAGS 0x3UL
118#define __DST_METRICS_PTR(Y) \
119 ((u32 *)((Y) & ~DST_METRICS_FLAGS))
120#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
121
122static inline bool dst_metrics_read_only(const struct dst_entry *dst)
123{
124 return dst->_metrics & DST_METRICS_READ_ONLY;
125}
126
127void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
128
129static inline void dst_destroy_metrics_generic(struct dst_entry *dst)
130{
131 unsigned long val = dst->_metrics;
132 if (!(val & DST_METRICS_READ_ONLY))
133 __dst_destroy_metrics_generic(dst, val);
134}
135
136static inline u32 *dst_metrics_write_ptr(struct dst_entry *dst)
137{
138 unsigned long p = dst->_metrics;
139
140 BUG_ON(!p);
141
142 if (p & DST_METRICS_READ_ONLY)
143 return dst->ops->cow_metrics(dst, p);
144 return __DST_METRICS_PTR(p);
145}
146
147
148
149
150static inline void dst_init_metrics(struct dst_entry *dst,
151 const u32 *src_metrics,
152 bool read_only)
153{
154 dst->_metrics = ((unsigned long) src_metrics) |
155 (read_only ? DST_METRICS_READ_ONLY : 0);
156}
157
158static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
159{
160 u32 *dst_metrics = dst_metrics_write_ptr(dest);
161
162 if (dst_metrics) {
163 u32 *src_metrics = DST_METRICS_PTR(src);
164
165 memcpy(dst_metrics, src_metrics, RTAX_MAX * sizeof(u32));
166 }
167}
168
169static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
170{
171 return DST_METRICS_PTR(dst);
172}
173
174static inline u32
175dst_metric_raw(const struct dst_entry *dst, const int metric)
176{
177 u32 *p = DST_METRICS_PTR(dst);
178
179 return p[metric-1];
180}
181
182static inline u32
183dst_metric(const struct dst_entry *dst, const int metric)
184{
185 WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
186 metric == RTAX_ADVMSS ||
187 metric == RTAX_MTU);
188 return dst_metric_raw(dst, metric);
189}
190
191static inline u32
192dst_metric_advmss(const struct dst_entry *dst)
193{
194 u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);
195
196 if (!advmss)
197 advmss = dst->ops->default_advmss(dst);
198
199 return advmss;
200}
201
202static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
203{
204 u32 *p = dst_metrics_write_ptr(dst);
205
206 if (p)
207 p[metric-1] = val;
208}
209
210
211#define DST_FEATURE_ECN_CA (1 << 31)
212
213#define DST_FEATURE_MASK (DST_FEATURE_ECN_CA)
214#define DST_FEATURE_ECN_MASK (DST_FEATURE_ECN_CA | RTAX_FEATURE_ECN)
215
216static inline u32
217dst_feature(const struct dst_entry *dst, u32 feature)
218{
219 return dst_metric(dst, RTAX_FEATURES) & feature;
220}
221
222static inline u32 dst_mtu(const struct dst_entry *dst)
223{
224 return dst->ops->mtu(dst);
225}
226
227
228static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
229{
230 return msecs_to_jiffies(dst_metric(dst, metric));
231}
232
233static inline u32
234dst_allfrag(const struct dst_entry *dst)
235{
236 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
237 return ret;
238}
239
240static inline int
241dst_metric_locked(const struct dst_entry *dst, int metric)
242{
243 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
244}
245
246static inline void dst_hold(struct dst_entry *dst)
247{
248
249
250
251
252 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
253 atomic_inc(&dst->__refcnt);
254}
255
256static inline void dst_use(struct dst_entry *dst, unsigned long time)
257{
258 dst_hold(dst);
259 dst->__use++;
260 dst->lastuse = time;
261}
262
263static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
264{
265 dst->__use++;
266 dst->lastuse = time;
267}
268
269static inline struct dst_entry *dst_clone(struct dst_entry *dst)
270{
271 if (dst)
272 atomic_inc(&dst->__refcnt);
273 return dst;
274}
275
276void dst_release(struct dst_entry *dst);
277
278static inline void refdst_drop(unsigned long refdst)
279{
280 if (!(refdst & SKB_DST_NOREF))
281 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
282}
283
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289
290static inline void skb_dst_drop(struct sk_buff *skb)
291{
292 if (skb->_skb_refdst) {
293 refdst_drop(skb->_skb_refdst);
294 skb->_skb_refdst = 0UL;
295 }
296}
297
298static inline void __skb_dst_copy(struct sk_buff *nskb, unsigned long refdst)
299{
300 nskb->_skb_refdst = refdst;
301 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
302 dst_clone(skb_dst(nskb));
303}
304
305static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
306{
307 __skb_dst_copy(nskb, oskb->_skb_refdst);
308}
309
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315
316static inline void skb_dst_force(struct sk_buff *skb)
317{
318 if (skb_dst_is_noref(skb)) {
319 WARN_ON(!rcu_read_lock_held());
320 skb->_skb_refdst &= ~SKB_DST_NOREF;
321 dst_clone(skb_dst(skb));
322 }
323}
324
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330
331
332static inline bool dst_hold_safe(struct dst_entry *dst)
333{
334 if (dst->flags & DST_NOCACHE)
335 return atomic_inc_not_zero(&dst->__refcnt);
336 dst_hold(dst);
337 return true;
338}
339
340
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343
344
345
346static inline void skb_dst_force_safe(struct sk_buff *skb)
347{
348 if (skb_dst_is_noref(skb)) {
349 struct dst_entry *dst = skb_dst(skb);
350
351 if (!dst_hold_safe(dst))
352 dst = NULL;
353
354 skb->_skb_refdst = (unsigned long)dst;
355 }
356}
357
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367
368static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
369 struct net *net)
370{
371 skb->dev = dev;
372
373
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375
376
377
378 skb_clear_hash_if_not_l4(skb);
379 skb_set_queue_mapping(skb, 0);
380 skb_scrub_packet(skb, !net_eq(net, dev_net(dev)));
381}
382
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390
391
392static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
393 struct net *net)
394{
395
396 dev->stats.rx_packets++;
397 dev->stats.rx_bytes += skb->len;
398 __skb_tunnel_rx(skb, dev, net);
399}
400
401int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
402static inline int dst_discard(struct sk_buff *skb)
403{
404 return dst_discard_out(&init_net, skb->sk, skb);
405}
406void *dst_alloc(struct dst_ops *ops, struct net_device *dev, int initial_ref,
407 int initial_obsolete, unsigned short flags);
408void dst_init(struct dst_entry *dst, struct dst_ops *ops,
409 struct net_device *dev, int initial_ref, int initial_obsolete,
410 unsigned short flags);
411void __dst_free(struct dst_entry *dst);
412struct dst_entry *dst_destroy(struct dst_entry *dst);
413
414static inline void dst_free(struct dst_entry *dst)
415{
416 if (dst->obsolete > 0)
417 return;
418 if (!atomic_read(&dst->__refcnt)) {
419 dst = dst_destroy(dst);
420 if (!dst)
421 return;
422 }
423 __dst_free(dst);
424}
425
426static inline void dst_rcu_free(struct rcu_head *head)
427{
428 struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
429 dst_free(dst);
430}
431
432static inline void dst_confirm(struct dst_entry *dst)
433{
434 dst->pending_confirm = 1;
435}
436
437static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n,
438 struct sk_buff *skb)
439{
440 const struct hh_cache *hh;
441
442 if (dst->pending_confirm) {
443 unsigned long now = jiffies;
444
445 dst->pending_confirm = 0;
446
447 if (n->confirmed != now)
448 n->confirmed = now;
449 }
450
451 hh = &n->hh;
452 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
453 return neigh_hh_output(hh, skb);
454 else
455 return n->output(n, skb);
456}
457
458static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
459{
460 struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
461 return IS_ERR(n) ? NULL : n;
462}
463
464static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
465 struct sk_buff *skb)
466{
467 struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
468 return IS_ERR(n) ? NULL : n;
469}
470
471static inline void dst_link_failure(struct sk_buff *skb)
472{
473 struct dst_entry *dst = skb_dst(skb);
474 if (dst && dst->ops && dst->ops->link_failure)
475 dst->ops->link_failure(skb);
476}
477
478static inline void dst_set_expires(struct dst_entry *dst, int timeout)
479{
480 unsigned long expires = jiffies + timeout;
481
482 if (expires == 0)
483 expires = 1;
484
485 if (dst->expires == 0 || time_before(expires, dst->expires))
486 dst->expires = expires;
487}
488
489
490static inline int dst_output(struct net *net, struct sock *sk, struct sk_buff *skb)
491{
492 return skb_dst(skb)->output(net, sk, skb);
493}
494
495
496static inline int dst_input(struct sk_buff *skb)
497{
498 return skb_dst(skb)->input(skb);
499}
500
501static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
502{
503 if (dst->obsolete)
504 dst = dst->ops->check(dst, cookie);
505 return dst;
506}
507
508void dst_subsys_init(void);
509
510
511enum {
512 XFRM_LOOKUP_ICMP = 1 << 0,
513 XFRM_LOOKUP_QUEUE = 1 << 1,
514 XFRM_LOOKUP_KEEP_DST_REF = 1 << 2,
515};
516
517struct flowi;
518#ifndef CONFIG_XFRM
519static inline struct dst_entry *xfrm_lookup(struct net *net,
520 struct dst_entry *dst_orig,
521 const struct flowi *fl,
522 const struct sock *sk,
523 int flags)
524{
525 return dst_orig;
526}
527
528static inline struct dst_entry *xfrm_lookup_route(struct net *net,
529 struct dst_entry *dst_orig,
530 const struct flowi *fl,
531 const struct sock *sk,
532 int flags)
533{
534 return dst_orig;
535}
536
537static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
538{
539 return NULL;
540}
541
542#else
543struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
544 const struct flowi *fl, const struct sock *sk,
545 int flags);
546
547struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
548 const struct flowi *fl, const struct sock *sk,
549 int flags);
550
551
552static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
553{
554 return dst->xfrm;
555}
556#endif
557
558#endif
559