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1/*
2 * net/dst.h Protocol independent destination cache definitions.
3 *
4 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
5 *
6 */
7
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/jiffies.h>
16#include <net/neighbour.h>
17#include <asm/processor.h>
18
19#define DST_GC_MIN (HZ/10)
20#define DST_GC_INC (HZ/2)
21#define DST_GC_MAX (120*HZ)
22
23/* Each dst_entry has reference count and sits in some parent list(s).
24 * When it is removed from parent list, it is "freed" (dst_free).
25 * After this it enters dead state (dst->obsolete > 0) and if its refcnt
26 * is zero, it can be destroyed immediately, otherwise it is added
27 * to gc list and garbage collector periodically checks the refcnt.
28 */
29
30struct sk_buff;
31
32struct dst_entry {
33 struct rcu_head rcu_head;
34 struct dst_entry *child;
35 struct net_device *dev;
36 struct dst_ops *ops;
37 unsigned long _metrics;
38 unsigned long expires;
39 struct dst_entry *path;
40 struct neighbour __rcu *_neighbour;
41#ifdef CONFIG_XFRM
42 struct xfrm_state *xfrm;
43#else
44 void *__pad1;
45#endif
46 int (*input)(struct sk_buff*);
47 int (*output)(struct sk_buff*);
48
49 int flags;
50#define DST_HOST 0x0001
51#define DST_NOXFRM 0x0002
52#define DST_NOPOLICY 0x0004
53#define DST_NOHASH 0x0008
54#define DST_NOCACHE 0x0010
55#define DST_NOCOUNT 0x0020
56
57 short error;
58 short obsolete;
59 unsigned short header_len; /* more space at head required */
60 unsigned short trailer_len; /* space to reserve at tail */
61#ifdef CONFIG_IP_ROUTE_CLASSID
62 __u32 tclassid;
63#else
64 __u32 __pad2;
65#endif
66
67 /*
68 * Align __refcnt to a 64 bytes alignment
69 * (L1_CACHE_SIZE would be too much)
70 */
71#ifdef CONFIG_64BIT
72 long __pad_to_align_refcnt[2];
73#endif
74 /*
75 * __refcnt wants to be on a different cache line from
76 * input/output/ops or performance tanks badly
77 */
78 atomic_t __refcnt; /* client references */
79 int __use;
80 unsigned long lastuse;
81 union {
82 struct dst_entry *next;
83 struct rtable __rcu *rt_next;
84 struct rt6_info *rt6_next;
85 struct dn_route __rcu *dn_next;
86 };
87};
88
89static inline struct neighbour *dst_get_neighbour(struct dst_entry *dst)
90{
91 return rcu_dereference(dst->_neighbour);
92}
93
94static inline struct neighbour *dst_get_neighbour_raw(struct dst_entry *dst)
95{
96 return rcu_dereference_raw(dst->_neighbour);
97}
98
99static inline void dst_set_neighbour(struct dst_entry *dst, struct neighbour *neigh)
100{
101 rcu_assign_pointer(dst->_neighbour, neigh);
102}
103
104extern u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
105extern const u32 dst_default_metrics[RTAX_MAX];
106
107#define DST_METRICS_READ_ONLY 0x1UL
108#define __DST_METRICS_PTR(Y) \
109 ((u32 *)((Y) & ~DST_METRICS_READ_ONLY))
110#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
111
112static inline bool dst_metrics_read_only(const struct dst_entry *dst)
113{
114 return dst->_metrics & DST_METRICS_READ_ONLY;
115}
116
117extern void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
118
119static inline void dst_destroy_metrics_generic(struct dst_entry *dst)
120{
121 unsigned long val = dst->_metrics;
122 if (!(val & DST_METRICS_READ_ONLY))
123 __dst_destroy_metrics_generic(dst, val);
124}
125
126static inline u32 *dst_metrics_write_ptr(struct dst_entry *dst)
127{
128 unsigned long p = dst->_metrics;
129
130 BUG_ON(!p);
131
132 if (p & DST_METRICS_READ_ONLY)
133 return dst->ops->cow_metrics(dst, p);
134 return __DST_METRICS_PTR(p);
135}
136
137/* This may only be invoked before the entry has reached global
138 * visibility.
139 */
140static inline void dst_init_metrics(struct dst_entry *dst,
141 const u32 *src_metrics,
142 bool read_only)
143{
144 dst->_metrics = ((unsigned long) src_metrics) |
145 (read_only ? DST_METRICS_READ_ONLY : 0);
146}
147
148static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
149{
150 u32 *dst_metrics = dst_metrics_write_ptr(dest);
151
152 if (dst_metrics) {
153 u32 *src_metrics = DST_METRICS_PTR(src);
154
155 memcpy(dst_metrics, src_metrics, RTAX_MAX * sizeof(u32));
156 }
157}
158
159static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
160{
161 return DST_METRICS_PTR(dst);
162}
163
164static inline u32
165dst_metric_raw(const struct dst_entry *dst, const int metric)
166{
167 u32 *p = DST_METRICS_PTR(dst);
168
169 return p[metric-1];
170}
171
172static inline u32
173dst_metric(const struct dst_entry *dst, const int metric)
174{
175 WARN_ON_ONCE(metric == RTAX_HOPLIMIT ||
176 metric == RTAX_ADVMSS ||
177 metric == RTAX_MTU);
178 return dst_metric_raw(dst, metric);
179}
180
181static inline u32
182dst_metric_advmss(const struct dst_entry *dst)
183{
184 u32 advmss = dst_metric_raw(dst, RTAX_ADVMSS);
185
186 if (!advmss)
187 advmss = dst->ops->default_advmss(dst);
188
189 return advmss;
190}
191
192static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
193{
194 u32 *p = dst_metrics_write_ptr(dst);
195
196 if (p)
197 p[metric-1] = val;
198}
199
200static inline u32
201dst_feature(const struct dst_entry *dst, u32 feature)
202{
203 return dst_metric(dst, RTAX_FEATURES) & feature;
204}
205
206static inline u32 dst_mtu(const struct dst_entry *dst)
207{
208 u32 mtu = dst_metric_raw(dst, RTAX_MTU);
209
210 if (!mtu)
211 mtu = dst->ops->default_mtu(dst);
212
213 return mtu;
214}
215
216/* RTT metrics are stored in milliseconds for user ABI, but used as jiffies */
217static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
218{
219 return msecs_to_jiffies(dst_metric(dst, metric));
220}
221
222static inline void set_dst_metric_rtt(struct dst_entry *dst, int metric,
223 unsigned long rtt)
224{
225 dst_metric_set(dst, metric, jiffies_to_msecs(rtt));
226}
227
228static inline u32
229dst_allfrag(const struct dst_entry *dst)
230{
231 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
232 return ret;
233}
234
235static inline int
236dst_metric_locked(const struct dst_entry *dst, int metric)
237{
238 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
239}
240
241static inline void dst_hold(struct dst_entry * dst)
242{
243 /*
244 * If your kernel compilation stops here, please check
245 * __pad_to_align_refcnt declaration in struct dst_entry
246 */
247 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
248 atomic_inc(&dst->__refcnt);
249}
250
251static inline void dst_use(struct dst_entry *dst, unsigned long time)
252{
253 dst_hold(dst);
254 dst->__use++;
255 dst->lastuse = time;
256}
257
258static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
259{
260 dst->__use++;
261 dst->lastuse = time;
262}
263
264static inline
265struct dst_entry * dst_clone(struct dst_entry * dst)
266{
267 if (dst)
268 atomic_inc(&dst->__refcnt);
269 return dst;
270}
271
272extern void dst_release(struct dst_entry *dst);
273
274static inline void refdst_drop(unsigned long refdst)
275{
276 if (!(refdst & SKB_DST_NOREF))
277 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
278}
279
280/**
281 * skb_dst_drop - drops skb dst
282 * @skb: buffer
283 *
284 * Drops dst reference count if a reference was taken.
285 */
286static inline void skb_dst_drop(struct sk_buff *skb)
287{
288 if (skb->_skb_refdst) {
289 refdst_drop(skb->_skb_refdst);
290 skb->_skb_refdst = 0UL;
291 }
292}
293
294static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
295{
296 nskb->_skb_refdst = oskb->_skb_refdst;
297 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
298 dst_clone(skb_dst(nskb));
299}
300
301/**
302 * skb_dst_force - makes sure skb dst is refcounted
303 * @skb: buffer
304 *
305 * If dst is not yet refcounted, let's do it
306 */
307static inline void skb_dst_force(struct sk_buff *skb)
308{
309 if (skb_dst_is_noref(skb)) {
310 WARN_ON(!rcu_read_lock_held());
311 skb->_skb_refdst &= ~SKB_DST_NOREF;
312 dst_clone(skb_dst(skb));
313 }
314}
315
316
317/**
318 * __skb_tunnel_rx - prepare skb for rx reinsert
319 * @skb: buffer
320 * @dev: tunnel device
321 *
322 * After decapsulation, packet is going to re-enter (netif_rx()) our stack,
323 * so make some cleanups. (no accounting done)
324 */
325static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
326{
327 skb->dev = dev;
328 skb->rxhash = 0;
329 skb_set_queue_mapping(skb, 0);
330 skb_dst_drop(skb);
331 nf_reset(skb);
332}
333
334/**
335 * skb_tunnel_rx - prepare skb for rx reinsert
336 * @skb: buffer
337 * @dev: tunnel device
338 *
339 * After decapsulation, packet is going to re-enter (netif_rx()) our stack,
340 * so make some cleanups, and perform accounting.
341 * Note: this accounting is not SMP safe.
342 */
343static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
344{
345 /* TODO : stats should be SMP safe */
346 dev->stats.rx_packets++;
347 dev->stats.rx_bytes += skb->len;
348 __skb_tunnel_rx(skb, dev);
349}
350
351/* Children define the path of the packet through the
352 * Linux networking. Thus, destinations are stackable.
353 */
354
355static inline struct dst_entry *skb_dst_pop(struct sk_buff *skb)
356{
357 struct dst_entry *child = dst_clone(skb_dst(skb)->child);
358
359 skb_dst_drop(skb);
360 return child;
361}
362
363extern int dst_discard(struct sk_buff *skb);
364extern void *dst_alloc(struct dst_ops * ops, struct net_device *dev,
365 int initial_ref, int initial_obsolete, int flags);
366extern void __dst_free(struct dst_entry * dst);
367extern struct dst_entry *dst_destroy(struct dst_entry * dst);
368
369static inline void dst_free(struct dst_entry * dst)
370{
371 if (dst->obsolete > 1)
372 return;
373 if (!atomic_read(&dst->__refcnt)) {
374 dst = dst_destroy(dst);
375 if (!dst)
376 return;
377 }
378 __dst_free(dst);
379}
380
381static inline void dst_rcu_free(struct rcu_head *head)
382{
383 struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
384 dst_free(dst);
385}
386
387static inline void dst_confirm(struct dst_entry *dst)
388{
389 if (dst) {
390 struct neighbour *n;
391
392 rcu_read_lock();
393 n = dst_get_neighbour(dst);
394 neigh_confirm(n);
395 rcu_read_unlock();
396 }
397}
398
399static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
400{
401 return dst->ops->neigh_lookup(dst, daddr);
402}
403
404static inline void dst_link_failure(struct sk_buff *skb)
405{
406 struct dst_entry *dst = skb_dst(skb);
407 if (dst && dst->ops && dst->ops->link_failure)
408 dst->ops->link_failure(skb);
409}
410
411static inline void dst_set_expires(struct dst_entry *dst, int timeout)
412{
413 unsigned long expires = jiffies + timeout;
414
415 if (expires == 0)
416 expires = 1;
417
418 if (dst->expires == 0 || time_before(expires, dst->expires))
419 dst->expires = expires;
420}
421
422/* Output packet to network from transport. */
423static inline int dst_output(struct sk_buff *skb)
424{
425 return skb_dst(skb)->output(skb);
426}
427
428/* Input packet from network to transport. */
429static inline int dst_input(struct sk_buff *skb)
430{
431 return skb_dst(skb)->input(skb);
432}
433
434static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
435{
436 if (dst->obsolete)
437 dst = dst->ops->check(dst, cookie);
438 return dst;
439}
440
441extern void dst_init(void);
442
443/* Flags for xfrm_lookup flags argument. */
444enum {
445 XFRM_LOOKUP_ICMP = 1 << 0,
446};
447
448struct flowi;
449#ifndef CONFIG_XFRM
450static inline struct dst_entry *xfrm_lookup(struct net *net,
451 struct dst_entry *dst_orig,
452 const struct flowi *fl, struct sock *sk,
453 int flags)
454{
455 return dst_orig;
456}
457#else
458extern struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
459 const struct flowi *fl, struct sock *sk,
460 int flags);
461#endif
462
463#endif /* _NET_DST_H */
1/*
2 * net/dst.h Protocol independent destination cache definitions.
3 *
4 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
5 *
6 */
7
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/* Each dst_entry has reference count and sits in some parent list(s).
25 * When it is removed from parent list, it is "freed" (dst_free).
26 * After this it enters dead state (dst->obsolete > 0) and if its refcnt
27 * is zero, it can be destroyed immediately, otherwise it is added
28 * to gc list and garbage collector periodically checks the refcnt.
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 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
61 unsigned short pending_confirm;
62
63 short error;
64
65 /* A non-zero value of dst->obsolete forces by-hand validation
66 * of the route entry. Positive values are set by the generic
67 * dst layer to indicate that the entry has been forcefully
68 * destroyed.
69 *
70 * Negative values are used by the implementation layer code to
71 * force invocation of the dst_ops->check() method.
72 */
73 short obsolete;
74#define DST_OBSOLETE_NONE 0
75#define DST_OBSOLETE_DEAD 2
76#define DST_OBSOLETE_FORCE_CHK -1
77#define DST_OBSOLETE_KILL -2
78 unsigned short header_len; /* more space at head required */
79 unsigned short trailer_len; /* space to reserve at tail */
80#ifdef CONFIG_IP_ROUTE_CLASSID
81 __u32 tclassid;
82#else
83 __u32 __pad2;
84#endif
85
86 /*
87 * Align __refcnt to a 64 bytes alignment
88 * (L1_CACHE_SIZE would be too much)
89 */
90#ifdef CONFIG_64BIT
91 long __pad_to_align_refcnt[2];
92#endif
93 /*
94 * __refcnt wants to be on a different cache line from
95 * input/output/ops or performance tanks badly
96 */
97 atomic_t __refcnt; /* client references */
98 int __use;
99 unsigned long lastuse;
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
108u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
109extern const u32 dst_default_metrics[];
110
111#define DST_METRICS_READ_ONLY 0x1UL
112#define DST_METRICS_FORCE_OVERWRITE 0x2UL
113#define DST_METRICS_FLAGS 0x3UL
114#define __DST_METRICS_PTR(Y) \
115 ((u32 *)((Y) & ~DST_METRICS_FLAGS))
116#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
117
118static inline bool dst_metrics_read_only(const struct dst_entry *dst)
119{
120 return dst->_metrics & DST_METRICS_READ_ONLY;
121}
122
123static inline void dst_metrics_set_force_overwrite(struct dst_entry *dst)
124{
125 dst->_metrics |= DST_METRICS_FORCE_OVERWRITE;
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/* This may only be invoked before the entry has reached global
149 * visibility.
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
211static inline u32
212dst_feature(const struct dst_entry *dst, u32 feature)
213{
214 return dst_metric(dst, RTAX_FEATURES) & feature;
215}
216
217static inline u32 dst_mtu(const struct dst_entry *dst)
218{
219 return dst->ops->mtu(dst);
220}
221
222/* RTT metrics are stored in milliseconds for user ABI, but used as jiffies */
223static inline unsigned long dst_metric_rtt(const struct dst_entry *dst, int metric)
224{
225 return msecs_to_jiffies(dst_metric(dst, metric));
226}
227
228static inline u32
229dst_allfrag(const struct dst_entry *dst)
230{
231 int ret = dst_feature(dst, RTAX_FEATURE_ALLFRAG);
232 return ret;
233}
234
235static inline int
236dst_metric_locked(const struct dst_entry *dst, int metric)
237{
238 return dst_metric(dst, RTAX_LOCK) & (1<<metric);
239}
240
241static inline void dst_hold(struct dst_entry *dst)
242{
243 /*
244 * If your kernel compilation stops here, please check
245 * __pad_to_align_refcnt declaration in struct dst_entry
246 */
247 BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
248 atomic_inc(&dst->__refcnt);
249}
250
251static inline void dst_use(struct dst_entry *dst, unsigned long time)
252{
253 dst_hold(dst);
254 dst->__use++;
255 dst->lastuse = time;
256}
257
258static inline void dst_use_noref(struct dst_entry *dst, unsigned long time)
259{
260 dst->__use++;
261 dst->lastuse = time;
262}
263
264static inline struct dst_entry *dst_clone(struct dst_entry *dst)
265{
266 if (dst)
267 atomic_inc(&dst->__refcnt);
268 return dst;
269}
270
271void dst_release(struct dst_entry *dst);
272
273static inline void refdst_drop(unsigned long refdst)
274{
275 if (!(refdst & SKB_DST_NOREF))
276 dst_release((struct dst_entry *)(refdst & SKB_DST_PTRMASK));
277}
278
279/**
280 * skb_dst_drop - drops skb dst
281 * @skb: buffer
282 *
283 * Drops dst reference count if a reference was taken.
284 */
285static inline void skb_dst_drop(struct sk_buff *skb)
286{
287 if (skb->_skb_refdst) {
288 refdst_drop(skb->_skb_refdst);
289 skb->_skb_refdst = 0UL;
290 }
291}
292
293static inline void skb_dst_copy(struct sk_buff *nskb, const struct sk_buff *oskb)
294{
295 nskb->_skb_refdst = oskb->_skb_refdst;
296 if (!(nskb->_skb_refdst & SKB_DST_NOREF))
297 dst_clone(skb_dst(nskb));
298}
299
300/**
301 * skb_dst_force - makes sure skb dst is refcounted
302 * @skb: buffer
303 *
304 * If dst is not yet refcounted, let's do it
305 */
306static inline void skb_dst_force(struct sk_buff *skb)
307{
308 if (skb_dst_is_noref(skb)) {
309 WARN_ON(!rcu_read_lock_held());
310 skb->_skb_refdst &= ~SKB_DST_NOREF;
311 dst_clone(skb_dst(skb));
312 }
313}
314
315
316/**
317 * __skb_tunnel_rx - prepare skb for rx reinsert
318 * @skb: buffer
319 * @dev: tunnel device
320 * @net: netns for packet i/o
321 *
322 * After decapsulation, packet is going to re-enter (netif_rx()) our stack,
323 * so make some cleanups. (no accounting done)
324 */
325static inline void __skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
326 struct net *net)
327{
328 skb->dev = dev;
329
330 /*
331 * Clear hash so that we can recalulate the hash for the
332 * encapsulated packet, unless we have already determine the hash
333 * over the L4 4-tuple.
334 */
335 skb_clear_hash_if_not_l4(skb);
336 skb_set_queue_mapping(skb, 0);
337 skb_scrub_packet(skb, !net_eq(net, dev_net(dev)));
338}
339
340/**
341 * skb_tunnel_rx - prepare skb for rx reinsert
342 * @skb: buffer
343 * @dev: tunnel device
344 *
345 * After decapsulation, packet is going to re-enter (netif_rx()) our stack,
346 * so make some cleanups, and perform accounting.
347 * Note: this accounting is not SMP safe.
348 */
349static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
350 struct net *net)
351{
352 /* TODO : stats should be SMP safe */
353 dev->stats.rx_packets++;
354 dev->stats.rx_bytes += skb->len;
355 __skb_tunnel_rx(skb, dev, net);
356}
357
358/* Children define the path of the packet through the
359 * Linux networking. Thus, destinations are stackable.
360 */
361
362static inline struct dst_entry *skb_dst_pop(struct sk_buff *skb)
363{
364 struct dst_entry *child = dst_clone(skb_dst(skb)->child);
365
366 skb_dst_drop(skb);
367 return child;
368}
369
370int dst_discard_sk(struct sock *sk, struct sk_buff *skb);
371static inline int dst_discard(struct sk_buff *skb)
372{
373 return dst_discard_sk(skb->sk, skb);
374}
375void *dst_alloc(struct dst_ops *ops, struct net_device *dev, int initial_ref,
376 int initial_obsolete, unsigned short flags);
377void __dst_free(struct dst_entry *dst);
378struct dst_entry *dst_destroy(struct dst_entry *dst);
379
380static inline void dst_free(struct dst_entry *dst)
381{
382 if (dst->obsolete > 0)
383 return;
384 if (!atomic_read(&dst->__refcnt)) {
385 dst = dst_destroy(dst);
386 if (!dst)
387 return;
388 }
389 __dst_free(dst);
390}
391
392static inline void dst_rcu_free(struct rcu_head *head)
393{
394 struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
395 dst_free(dst);
396}
397
398static inline void dst_confirm(struct dst_entry *dst)
399{
400 dst->pending_confirm = 1;
401}
402
403static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n,
404 struct sk_buff *skb)
405{
406 const struct hh_cache *hh;
407
408 if (dst->pending_confirm) {
409 unsigned long now = jiffies;
410
411 dst->pending_confirm = 0;
412 /* avoid dirtying neighbour */
413 if (n->confirmed != now)
414 n->confirmed = now;
415 }
416
417 hh = &n->hh;
418 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
419 return neigh_hh_output(hh, skb);
420 else
421 return n->output(n, skb);
422}
423
424static inline struct neighbour *dst_neigh_lookup(const struct dst_entry *dst, const void *daddr)
425{
426 struct neighbour *n = dst->ops->neigh_lookup(dst, NULL, daddr);
427 return IS_ERR(n) ? NULL : n;
428}
429
430static inline struct neighbour *dst_neigh_lookup_skb(const struct dst_entry *dst,
431 struct sk_buff *skb)
432{
433 struct neighbour *n = dst->ops->neigh_lookup(dst, skb, NULL);
434 return IS_ERR(n) ? NULL : n;
435}
436
437static inline void dst_link_failure(struct sk_buff *skb)
438{
439 struct dst_entry *dst = skb_dst(skb);
440 if (dst && dst->ops && dst->ops->link_failure)
441 dst->ops->link_failure(skb);
442}
443
444static inline void dst_set_expires(struct dst_entry *dst, int timeout)
445{
446 unsigned long expires = jiffies + timeout;
447
448 if (expires == 0)
449 expires = 1;
450
451 if (dst->expires == 0 || time_before(expires, dst->expires))
452 dst->expires = expires;
453}
454
455/* Output packet to network from transport. */
456static inline int dst_output_sk(struct sock *sk, struct sk_buff *skb)
457{
458 return skb_dst(skb)->output(sk, skb);
459}
460static inline int dst_output(struct sk_buff *skb)
461{
462 return dst_output_sk(skb->sk, skb);
463}
464
465/* Input packet from network to transport. */
466static inline int dst_input(struct sk_buff *skb)
467{
468 return skb_dst(skb)->input(skb);
469}
470
471static inline struct dst_entry *dst_check(struct dst_entry *dst, u32 cookie)
472{
473 if (dst->obsolete)
474 dst = dst->ops->check(dst, cookie);
475 return dst;
476}
477
478void dst_init(void);
479
480/* Flags for xfrm_lookup flags argument. */
481enum {
482 XFRM_LOOKUP_ICMP = 1 << 0,
483};
484
485struct flowi;
486#ifndef CONFIG_XFRM
487static inline struct dst_entry *xfrm_lookup(struct net *net,
488 struct dst_entry *dst_orig,
489 const struct flowi *fl, struct sock *sk,
490 int flags)
491{
492 return dst_orig;
493}
494
495static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
496{
497 return NULL;
498}
499
500#else
501struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
502 const struct flowi *fl, struct sock *sk,
503 int flags);
504
505/* skb attached with this dst needs transformation if dst->xfrm is valid */
506static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
507{
508 return dst->xfrm;
509}
510#endif
511
512#endif /* _NET_DST_H */