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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
22#define DST_GC_MIN (HZ/10)
23#define DST_GC_INC (HZ/2)
24#define DST_GC_MAX (120*HZ)
25
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30
31
32
33struct sk_buff;
34
35struct dst_entry {
36 struct net_device *dev;
37 struct rcu_head rcu_head;
38 struct dst_entry *child;
39 struct dst_ops *ops;
40 unsigned long _metrics;
41 unsigned long expires;
42 struct dst_entry *path;
43 struct dst_entry *from;
44#ifdef CONFIG_XFRM
45 struct xfrm_state *xfrm;
46#else
47 void *__pad1;
48#endif
49 int (*input)(struct sk_buff *);
50 int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
51
52 unsigned short flags;
53#define DST_HOST 0x0001
54#define DST_NOXFRM 0x0002
55#define DST_NOPOLICY 0x0004
56#define DST_NOCOUNT 0x0008
57#define DST_FAKE_RTABLE 0x0010
58#define DST_XFRM_TUNNEL 0x0020
59#define DST_XFRM_QUEUE 0x0040
60#define DST_METADATA 0x0080
61
62 short error;
63
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70
71
72 short obsolete;
73#define DST_OBSOLETE_NONE 0
74#define DST_OBSOLETE_DEAD 2
75#define DST_OBSOLETE_FORCE_CHK -1
76#define DST_OBSOLETE_KILL -2
77 unsigned short header_len;
78 unsigned short trailer_len;
79 unsigned short __pad3;
80
81#ifdef CONFIG_IP_ROUTE_CLASSID
82 __u32 tclassid;
83#else
84 __u32 __pad2;
85#endif
86
87#ifdef CONFIG_64BIT
88
89
90
91
92 long __pad_to_align_refcnt[2];
93#endif
94
95
96
97
98 atomic_t __refcnt;
99 int __use;
100 unsigned long lastuse;
101 struct lwtunnel_state *lwtstate;
102 union {
103 struct dst_entry *next;
104 struct rtable __rcu *rt_next;
105 struct rt6_info *rt6_next;
106 struct dn_route __rcu *dn_next;
107 };
108};
109
110struct dst_metrics {
111 u32 metrics[RTAX_MAX];
112 refcount_t refcnt;
113};
114extern const struct dst_metrics dst_default_metrics;
115
116u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
117
118#define DST_METRICS_READ_ONLY 0x1UL
119#define DST_METRICS_REFCOUNTED 0x2UL
120#define DST_METRICS_FLAGS 0x3UL
121#define __DST_METRICS_PTR(Y) \
122 ((u32 *)((Y) & ~DST_METRICS_FLAGS))
123#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
124
125static inline bool dst_metrics_read_only(const struct dst_entry *dst)
126{
127 return dst->_metrics & DST_METRICS_READ_ONLY;
128}
129
130void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
131
132static inline void dst_destroy_metrics_generic(struct dst_entry *dst)
133{
134 unsigned long val = dst->_metrics;
135 if (!(val & DST_METRICS_READ_ONLY))
136 __dst_destroy_metrics_generic(dst, val);
137}
138
139static inline u32 *dst_metrics_write_ptr(struct dst_entry *dst)
140{
141 unsigned long p = dst->_metrics;
142
143 BUG_ON(!p);
144
145 if (p & DST_METRICS_READ_ONLY)
146 return dst->ops->cow_metrics(dst, p);
147 return __DST_METRICS_PTR(p);
148}
149
150
151
152
153static inline void dst_init_metrics(struct dst_entry *dst,
154 const u32 *src_metrics,
155 bool read_only)
156{
157 dst->_metrics = ((unsigned long) src_metrics) |
158 (read_only ? DST_METRICS_READ_ONLY : 0);
159}
160
161static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
162{
163 u32 *dst_metrics = dst_metrics_write_ptr(dest);
164
165 if (dst_metrics) {
166 u32 *src_metrics = DST_METRICS_PTR(src);
167
168 memcpy(dst_metrics, src_metrics, RTAX_MAX * sizeof(u32));
169 }
170}
171
172static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
173{
174 return DST_METRICS_PTR(dst);
175}
176
177static inline u32
178dst_metric_raw(const struct dst_entry *dst, const int metric)
179{
180 u32 *p = DST_METRICS_PTR(dst);
181
182 return p[metric-1];
183}
184
185static inline u32
186dst_metric(const struct dst_entry *dst, const int metric)
187{
188 WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
189 metric == RTAX_ADVMSS ||
190 metric == RTAX_MTU);
191 return dst_metric_raw(dst, metric);
192}
193
194static inline u32
195dst_metric_advmss(const struct dst_entry *dst)
196{
197 u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);
198
199 if (!advmss)
200 advmss = dst->ops->default_advmss(dst);
201
202 return advmss;
203}
204
205static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
206{
207 u32 *p = dst_metrics_write_ptr(dst);
208
209 if (p)
210 p[metric-1] = val;
211}
212
213
214#define DST_FEATURE_ECN_CA (1 << 31)
215
216#define DST_FEATURE_MASK (DST_FEATURE_ECN_CA)
217#define DST_FEATURE_ECN_MASK (DST_FEATURE_ECN_CA | RTAX_FEATURE_ECN)
218
219static inline u32
220dst_feature(const struct dst_entry *dst, u32 feature)
221{
222 return dst_metric(dst, RTAX_FEATURES) & feature;
223}
224
225static inline u32 dst_mtu(const struct dst_entry *dst)
226{
227 return dst->ops->mtu(dst);
228}
229
230
231static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
232{
233 return msecs_to_jiffies(dst_metric(dst, metric));
234}
235
236static inline u32
237dst_allfrag(const struct dst_entry *dst)
238{
239 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
240 return ret;
241}
242
243static inline int
244dst_metric_locked(const struct dst_entry *dst, int metric)
245{
246 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
247}
248
249static inline void dst_hold(struct dst_entry *dst)
250{
251
252
253
254
255 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
256 WARN_ON(atomic_inc_not_zero(&dst->__refcnt) == 0);
257}
258
259static inline void dst_use(struct dst_entry *dst, unsigned long time)
260{
261 dst_hold(dst);
262 dst->__use++;
263 dst->lastuse = time;
264}
265
266static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
267{
268 dst->__use++;
269 dst->lastuse = time;
270}
271
272static inline struct dst_entry *dst_clone(struct dst_entry *dst)
273{
274 if (dst)
275 dst_hold(dst);
276 return dst;
277}
278
279void dst_release(struct dst_entry *dst);
280
281void dst_release_immediate(struct dst_entry *dst);
282
283static inline void refdst_drop(unsigned long refdst)
284{
285 if (!(refdst & SKB_DST_NOREF))
286 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
287}
288
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294
295static inline void skb_dst_drop(struct sk_buff *skb)
296{
297 if (skb->_skb_refdst) {
298 refdst_drop(skb->_skb_refdst);
299 skb->_skb_refdst = 0UL;
300 }
301}
302
303static inline void __skb_dst_copy(struct sk_buff *nskb, unsigned long refdst)
304{
305 nskb->_skb_refdst = refdst;
306 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
307 dst_clone(skb_dst(nskb));
308}
309
310static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
311{
312 __skb_dst_copy(nskb, oskb->_skb_refdst);
313}
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321
322static inline bool dst_hold_safe(struct dst_entry *dst)
323{
324 return atomic_inc_not_zero(&dst->__refcnt);
325}
326
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331
332
333static inline void skb_dst_force(struct sk_buff *skb)
334{
335 if (skb_dst_is_noref(skb)) {
336 struct dst_entry *dst = skb_dst(skb);
337
338 WARN_ON(!rcu_read_lock_held());
339 if (!dst_hold_safe(dst))
340 dst = NULL;
341
342 skb->_skb_refdst = (unsigned long)dst;
343 }
344}
345
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355
356static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
357 struct net *net)
358{
359 skb->dev = dev;
360
361
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363
364
365
366 skb_clear_hash_if_not_l4(skb);
367 skb_set_queue_mapping(skb, 0);
368 skb_scrub_packet(skb, !net_eq(net, dev_net(dev)));
369}
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379
380static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
381 struct net *net)
382{
383
384 dev->stats.rx_packets++;
385 dev->stats.rx_bytes += skb->len;
386 __skb_tunnel_rx(skb, dev, net);
387}
388
389static inline u32 dst_tclassid(const struct sk_buff *skb)
390{
391#ifdef CONFIG_IP_ROUTE_CLASSID
392 const struct dst_entry *dst;
393
394 dst = skb_dst(skb);
395 if (dst)
396 return dst->tclassid;
397#endif
398 return 0;
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);
411struct dst_entry *dst_destroy(struct dst_entry *dst);
412void dst_dev_put(struct dst_entry *dst);
413
414static inline void dst_confirm(struct dst_entry *dst)
415{
416}
417
418static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
419{
420 struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
421 return IS_ERR(n) ? NULL : n;
422}
423
424static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
425 struct sk_buff *skb)
426{
427 struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
428 return IS_ERR(n) ? NULL : n;
429}
430
431static inline void dst_confirm_neigh(const struct dst_entry *dst,
432 const void *daddr)
433{
434 if (dst->ops->confirm_neigh)
435 dst->ops->confirm_neigh(dst, daddr);
436}
437
438static inline void dst_link_failure(struct sk_buff *skb)
439{
440 struct dst_entry *dst = skb_dst(skb);
441 if (dst && dst->ops && dst->ops->link_failure)
442 dst->ops->link_failure(skb);
443}
444
445static inline void dst_set_expires(struct dst_entry *dst, int timeout)
446{
447 unsigned long expires = jiffies + timeout;
448
449 if (expires == 0)
450 expires = 1;
451
452 if (dst->expires == 0 || time_before(expires, dst->expires))
453 dst->expires = expires;
454}
455
456
457static inline int dst_output(struct net *net, struct sock *sk, struct sk_buff *skb)
458{
459 return skb_dst(skb)->output(net, sk, skb);
460}
461
462
463static inline int dst_input(struct sk_buff *skb)
464{
465 return skb_dst(skb)->input(skb);
466}
467
468static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
469{
470 if (dst->obsolete)
471 dst = dst->ops->check(dst, cookie);
472 return dst;
473}
474
475
476enum {
477 XFRM_LOOKUP_ICMP = 1 << 0,
478 XFRM_LOOKUP_QUEUE = 1 << 1,
479 XFRM_LOOKUP_KEEP_DST_REF = 1 << 2,
480};
481
482struct flowi;
483#ifndef CONFIG_XFRM
484static inline struct dst_entry *xfrm_lookup(struct net *net,
485 struct dst_entry *dst_orig,
486 const struct flowi *fl,
487 const struct sock *sk,
488 int flags)
489{
490 return dst_orig;
491}
492
493static inline struct dst_entry *xfrm_lookup_route(struct net *net,
494 struct dst_entry *dst_orig,
495 const struct flowi *fl,
496 const struct sock *sk,
497 int flags)
498{
499 return dst_orig;
500}
501
502static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
503{
504 return NULL;
505}
506
507#else
508struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
509 const struct flowi *fl, const struct sock *sk,
510 int flags);
511
512struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
513 const struct flowi *fl, const struct sock *sk,
514 int flags);
515
516
517static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
518{
519 return dst->xfrm;
520}
521#endif
522
523#endif
524