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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
25
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28
29
30
31struct sk_buff;
32
33struct dst_entry {
34 struct net_device *dev;
35 struct rcu_head rcu_head;
36 struct dst_entry *child;
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_NOCOUNT 0x0008
55#define DST_FAKE_RTABLE 0x0010
56#define DST_XFRM_TUNNEL 0x0020
57#define DST_XFRM_QUEUE 0x0040
58#define DST_METADATA 0x0080
59
60 short error;
61
62
63
64
65
66
67
68
69
70 short obsolete;
71#define DST_OBSOLETE_NONE 0
72#define DST_OBSOLETE_DEAD 2
73#define DST_OBSOLETE_FORCE_CHK -1
74#define DST_OBSOLETE_KILL -2
75 unsigned short header_len;
76 unsigned short trailer_len;
77 unsigned short __pad3;
78
79#ifdef CONFIG_IP_ROUTE_CLASSID
80 __u32 tclassid;
81#else
82 __u32 __pad2;
83#endif
84
85#ifdef CONFIG_64BIT
86
87
88
89
90 long __pad_to_align_refcnt[2];
91#endif
92
93
94
95
96 atomic_t __refcnt;
97 int __use;
98 unsigned long lastuse;
99 struct lwtunnel_state *lwtstate;
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
108struct dst_metrics {
109 u32 metrics[RTAX_MAX];
110 atomic_t refcnt;
111};
112extern const struct dst_metrics dst_default_metrics;
113
114u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
115
116#define DST_METRICS_READ_ONLY 0x1UL
117#define DST_METRICS_REFCOUNTED 0x2UL
118#define DST_METRICS_FLAGS 0x3UL
119#define __DST_METRICS_PTR(Y) \
120 ((u32 *)((Y) & ~DST_METRICS_FLAGS))
121#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
122
123static inline bool dst_metrics_read_only(const struct dst_entry *dst)
124{
125 return dst->_metrics & DST_METRICS_READ_ONLY;
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
211
212#define DST_FEATURE_ECN_CA (1 << 31)
213
214#define DST_FEATURE_MASK (DST_FEATURE_ECN_CA)
215#define DST_FEATURE_ECN_MASK (DST_FEATURE_ECN_CA | RTAX_FEATURE_ECN)
216
217static inline u32
218dst_feature(const struct dst_entry *dst, u32 feature)
219{
220 return dst_metric(dst, RTAX_FEATURES) & feature;
221}
222
223static inline u32 dst_mtu(const struct dst_entry *dst)
224{
225 return dst->ops->mtu(dst);
226}
227
228
229static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
230{
231 return msecs_to_jiffies(dst_metric(dst, metric));
232}
233
234static inline u32
235dst_allfrag(const struct dst_entry *dst)
236{
237 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
238 return ret;
239}
240
241static inline int
242dst_metric_locked(const struct dst_entry *dst, int metric)
243{
244 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
245}
246
247static inline void dst_hold(struct dst_entry *dst)
248{
249
250
251
252
253 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
254 WARN_ON(atomic_inc_not_zero(&dst->__refcnt) == 0);
255}
256
257static inline void dst_use(struct dst_entry *dst, unsigned long time)
258{
259 dst_hold(dst);
260 dst->__use++;
261 dst->lastuse = time;
262}
263
264static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
265{
266 dst->__use++;
267 dst->lastuse = time;
268}
269
270static inline struct dst_entry *dst_clone(struct dst_entry *dst)
271{
272 if (dst)
273 atomic_inc(&dst->__refcnt);
274 return dst;
275}
276
277void dst_release(struct dst_entry *dst);
278
279void dst_release_immediate(struct dst_entry *dst);
280
281static inline void refdst_drop(unsigned long refdst)
282{
283 if (!(refdst & SKB_DST_NOREF))
284 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
285}
286
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292
293static inline void skb_dst_drop(struct sk_buff *skb)
294{
295 if (skb->_skb_refdst) {
296 refdst_drop(skb->_skb_refdst);
297 skb->_skb_refdst = 0UL;
298 }
299}
300
301static inline void __skb_dst_copy(struct sk_buff *nskb, unsigned long refdst)
302{
303 nskb->_skb_refdst = refdst;
304 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
305 dst_clone(skb_dst(nskb));
306}
307
308static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
309{
310 __skb_dst_copy(nskb, oskb->_skb_refdst);
311}
312
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318
319static inline void skb_dst_force(struct sk_buff *skb)
320{
321 if (skb_dst_is_noref(skb)) {
322 WARN_ON(!rcu_read_lock_held());
323 skb->_skb_refdst &= ~SKB_DST_NOREF;
324 dst_clone(skb_dst(skb));
325 }
326}
327
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334
335static inline bool dst_hold_safe(struct dst_entry *dst)
336{
337 return atomic_inc_not_zero(&dst->__refcnt);
338}
339
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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
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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}
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389
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
401static inline u32 dst_tclassid(const struct sk_buff *skb)
402{
403#ifdef CONFIG_IP_ROUTE_CLASSID
404 const struct dst_entry *dst;
405
406 dst = skb_dst(skb);
407 if (dst)
408 return dst->tclassid;
409#endif
410 return 0;
411}
412
413int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
414static inline int dst_discard(struct sk_buff *skb)
415{
416 return dst_discard_out(&init_net, skb->sk, skb);
417}
418void *dst_alloc(struct dst_ops *ops, struct net_device *dev, int initial_ref,
419 int initial_obsolete, unsigned short flags);
420void dst_init(struct dst_entry *dst, struct dst_ops *ops,
421 struct net_device *dev, int initial_ref, int initial_obsolete,
422 unsigned short flags);
423struct dst_entry *dst_destroy(struct dst_entry *dst);
424void dst_dev_put(struct dst_entry *dst);
425
426static inline void dst_confirm(struct dst_entry *dst)
427{
428}
429
430static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
431{
432 struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
433 return IS_ERR(n) ? NULL : n;
434}
435
436static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
437 struct sk_buff *skb)
438{
439 struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
440 return IS_ERR(n) ? NULL : n;
441}
442
443static inline void dst_confirm_neigh(const struct dst_entry *dst,
444 const void *daddr)
445{
446 if (dst->ops->confirm_neigh)
447 dst->ops->confirm_neigh(dst, daddr);
448}
449
450static inline void dst_link_failure(struct sk_buff *skb)
451{
452 struct dst_entry *dst = skb_dst(skb);
453 if (dst && dst->ops && dst->ops->link_failure)
454 dst->ops->link_failure(skb);
455}
456
457static inline void dst_set_expires(struct dst_entry *dst, int timeout)
458{
459 unsigned long expires = jiffies + timeout;
460
461 if (expires == 0)
462 expires = 1;
463
464 if (dst->expires == 0 || time_before(expires, dst->expires))
465 dst->expires = expires;
466}
467
468
469static inline int dst_output(struct net *net, struct sock *sk, struct sk_buff *skb)
470{
471 return skb_dst(skb)->output(net, sk, skb);
472}
473
474
475static inline int dst_input(struct sk_buff *skb)
476{
477 return skb_dst(skb)->input(skb);
478}
479
480static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
481{
482 if (dst->obsolete)
483 dst = dst->ops->check(dst, cookie);
484 return dst;
485}
486
487
488enum {
489 XFRM_LOOKUP_ICMP = 1 << 0,
490 XFRM_LOOKUP_QUEUE = 1 << 1,
491 XFRM_LOOKUP_KEEP_DST_REF = 1 << 2,
492};
493
494struct flowi;
495#ifndef CONFIG_XFRM
496static inline struct dst_entry *xfrm_lookup(struct net *net,
497 struct dst_entry *dst_orig,
498 const struct flowi *fl,
499 const struct sock *sk,
500 int flags)
501{
502 return dst_orig;
503}
504
505static inline struct dst_entry *xfrm_lookup_route(struct net *net,
506 struct dst_entry *dst_orig,
507 const struct flowi *fl,
508 const struct sock *sk,
509 int flags)
510{
511 return dst_orig;
512}
513
514static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
515{
516 return NULL;
517}
518
519#else
520struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
521 const struct flowi *fl, const struct sock *sk,
522 int flags);
523
524struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
525 const struct flowi *fl, const struct sock *sk,
526 int flags);
527
528
529static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
530{
531 return dst->xfrm;
532}
533#endif
534
535#endif
536