This source file includes following definitions.
- dst_metrics_read_only
- dst_destroy_metrics_generic
- dst_metrics_write_ptr
- dst_init_metrics
- dst_copy_metrics
- dst_metrics_ptr
- dst_metric_raw
- dst_metric
- dst_metric_advmss
- dst_metric_set
- dst_feature
- dst_mtu
- dst_metric_rtt
- dst_allfrag
- dst_metric_locked
- dst_hold
- dst_use_noref
- dst_hold_and_use
- dst_clone
- refdst_drop
- skb_dst_drop
- __skb_dst_copy
- skb_dst_copy
- dst_hold_safe
- skb_dst_force
- __skb_tunnel_rx
- skb_tunnel_rx
- dst_tclassid
- dst_discard
- dst_confirm
- dst_neigh_lookup
- dst_neigh_lookup_skb
- dst_confirm_neigh
- dst_link_failure
- dst_set_expires
- dst_output
- dst_input
- dst_check
- xfrm_lookup
- xfrm_lookup_with_ifid
- xfrm_lookup_route
- dst_xfrm
- dst_xfrm
- skb_dst_update_pmtu
- skb_dst_update_pmtu_no_confirm
- skb_tunnel_check_pmtu
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8
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
22 struct sk_buff;
23
24 struct 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
48
49
50
51
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
82 struct dst_metrics {
83 u32 metrics[RTAX_MAX];
84 refcount_t refcnt;
85 } __aligned(4);
86 extern const struct dst_metrics dst_default_metrics;
87
88 u32 *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
97 static inline bool dst_metrics_read_only(const struct dst_entry *dst)
98 {
99 return dst->_metrics & DST_METRICS_READ_ONLY;
100 }
101
102 void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
103
104 static 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
111 static 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
125 static 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
133 static 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
144 static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
145 {
146 return DST_METRICS_PTR(dst);
147 }
148
149 static inline u32
150 dst_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
157 static inline u32
158 dst_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
166 static inline u32
167 dst_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
177 static 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 (1U << 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
191 static inline u32
192 dst_feature(const struct dst_entry *dst, u32 feature)
193 {
194 return dst_metric(dst, RTAX_FEATURES) & feature;
195 }
196
197 static inline u32 dst_mtu(const struct dst_entry *dst)
198 {
199 return dst->ops->mtu(dst);
200 }
201
202
203 static 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
208 static inline u32
209 dst_allfrag(const struct dst_entry *dst)
210 {
211 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
212 return ret;
213 }
214
215 static inline int
216 dst_metric_locked(const struct dst_entry *dst, int metric)
217 {
218 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
219 }
220
221 static 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
231 static 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
239 static 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
245 static inline struct dst_entry *dst_clone(struct dst_entry *dst)
246 {
247 if (dst)
248 dst_hold(dst);
249 return dst;
250 }
251
252 void dst_release(struct dst_entry *dst);
253
254 void dst_release_immediate(struct dst_entry *dst);
255
256 static 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
262
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264
265
266
267
268 static 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
276 static 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
283 static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
284 {
285 __skb_dst_copy(nskb, oskb->_skb_refdst);
286 }
287
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293
294
295 static inline bool dst_hold_safe(struct dst_entry *dst)
296 {
297 return atomic_inc_not_zero(&dst->__refcnt);
298 }
299
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306
307 static inline bool skb_dst_force(struct sk_buff *skb)
308 {
309 if (skb_dst_is_noref(skb)) {
310 struct dst_entry *dst = skb_dst(skb);
311
312 WARN_ON(!rcu_read_lock_held());
313 if (!dst_hold_safe(dst))
314 dst = NULL;
315
316 skb->_skb_refdst = (unsigned long)dst;
317 }
318
319 return skb->_skb_refdst != 0UL;
320 }
321
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330
331
332 static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
333 struct net *net)
334 {
335 skb->dev = dev;
336
337
338
339
340
341
342 skb_clear_hash_if_not_l4(skb);
343 skb_set_queue_mapping(skb, 0);
344 skb_scrub_packet(skb, !net_eq(net, dev_net(dev)));
345 }
346
347
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352
353
354
355
356
357 static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
358 struct net *net)
359 {
360
361 dev->stats.rx_packets++;
362 dev->stats.rx_bytes += skb->len;
363 __skb_tunnel_rx(skb, dev, net);
364 }
365
366 static inline u32 dst_tclassid(const struct sk_buff *skb)
367 {
368 #ifdef CONFIG_IP_ROUTE_CLASSID
369 const struct dst_entry *dst;
370
371 dst = skb_dst(skb);
372 if (dst)
373 return dst->tclassid;
374 #endif
375 return 0;
376 }
377
378 int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
379 static inline int dst_discard(struct sk_buff *skb)
380 {
381 return dst_discard_out(&init_net, skb->sk, skb);
382 }
383 void *dst_alloc(struct dst_ops *ops, struct net_device *dev, int initial_ref,
384 int initial_obsolete, unsigned short flags);
385 void dst_init(struct dst_entry *dst, struct dst_ops *ops,
386 struct net_device *dev, int initial_ref, int initial_obsolete,
387 unsigned short flags);
388 struct dst_entry *dst_destroy(struct dst_entry *dst);
389 void dst_dev_put(struct dst_entry *dst);
390
391 static inline void dst_confirm(struct dst_entry *dst)
392 {
393 }
394
395 static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
396 {
397 struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
398 return IS_ERR(n) ? NULL : n;
399 }
400
401 static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
402 struct sk_buff *skb)
403 {
404 struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
405 return IS_ERR(n) ? NULL : n;
406 }
407
408 static inline void dst_confirm_neigh(const struct dst_entry *dst,
409 const void *daddr)
410 {
411 if (dst->ops->confirm_neigh)
412 dst->ops->confirm_neigh(dst, daddr);
413 }
414
415 static inline void dst_link_failure(struct sk_buff *skb)
416 {
417 struct dst_entry *dst = skb_dst(skb);
418 if (dst && dst->ops && dst->ops->link_failure)
419 dst->ops->link_failure(skb);
420 }
421
422 static inline void dst_set_expires(struct dst_entry *dst, int timeout)
423 {
424 unsigned long expires = jiffies + timeout;
425
426 if (expires == 0)
427 expires = 1;
428
429 if (dst->expires == 0 || time_before(expires, dst->expires))
430 dst->expires = expires;
431 }
432
433
434 static inline int dst_output(struct net *net, struct sock *sk, struct sk_buff *skb)
435 {
436 return skb_dst(skb)->output(net, sk, skb);
437 }
438
439
440 static inline int dst_input(struct sk_buff *skb)
441 {
442 return skb_dst(skb)->input(skb);
443 }
444
445 static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
446 {
447 if (dst->obsolete)
448 dst = dst->ops->check(dst, cookie);
449 return dst;
450 }
451
452
453 enum {
454 XFRM_LOOKUP_ICMP = 1 << 0,
455 XFRM_LOOKUP_QUEUE = 1 << 1,
456 XFRM_LOOKUP_KEEP_DST_REF = 1 << 2,
457 };
458
459 struct flowi;
460 #ifndef CONFIG_XFRM
461 static inline struct dst_entry *xfrm_lookup(struct net *net,
462 struct dst_entry *dst_orig,
463 const struct flowi *fl,
464 const struct sock *sk,
465 int flags)
466 {
467 return dst_orig;
468 }
469
470 static inline struct dst_entry *
471 xfrm_lookup_with_ifid(struct net *net, struct dst_entry *dst_orig,
472 const struct flowi *fl, const struct sock *sk,
473 int flags, u32 if_id)
474 {
475 return dst_orig;
476 }
477
478 static inline struct dst_entry *xfrm_lookup_route(struct net *net,
479 struct dst_entry *dst_orig,
480 const struct flowi *fl,
481 const struct sock *sk,
482 int flags)
483 {
484 return dst_orig;
485 }
486
487 static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
488 {
489 return NULL;
490 }
491
492 #else
493 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
494 const struct flowi *fl, const struct sock *sk,
495 int flags);
496
497 struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
498 struct dst_entry *dst_orig,
499 const struct flowi *fl,
500 const struct sock *sk, int flags,
501 u32 if_id);
502
503 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
504 const struct flowi *fl, const struct sock *sk,
505 int flags);
506
507
508 static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
509 {
510 return dst->xfrm;
511 }
512 #endif
513
514 static inline void skb_dst_update_pmtu(struct sk_buff *skb, u32 mtu)
515 {
516 struct dst_entry *dst = skb_dst(skb);
517
518 if (dst && dst->ops->update_pmtu)
519 dst->ops->update_pmtu(dst, NULL, skb, mtu, true);
520 }
521
522
523 static inline void skb_dst_update_pmtu_no_confirm(struct sk_buff *skb, u32 mtu)
524 {
525 struct dst_entry *dst = skb_dst(skb);
526
527 if (dst && dst->ops->update_pmtu)
528 dst->ops->update_pmtu(dst, NULL, skb, mtu, false);
529 }
530
531 static inline void skb_tunnel_check_pmtu(struct sk_buff *skb,
532 struct dst_entry *encap_dst,
533 int headroom)
534 {
535 u32 encap_mtu = dst_mtu(encap_dst);
536
537 if (skb->len > encap_mtu - headroom)
538 skb_dst_update_pmtu_no_confirm(skb, encap_mtu - headroom);
539 }
540
541 #endif